Index: head/share/man/man9/zone.9 =================================================================== --- head/share/man/man9/zone.9 (revision 355001) +++ head/share/man/man9/zone.9 (revision 355002) @@ -1,609 +1,606 @@ .\"- .\" Copyright (c) 2001 Dag-Erling Coïdan Smørgrav .\" All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" $FreeBSD$ .\" -.Dd September 1, 2019 +.Dd November 22, 2019 .Dt UMA 9 .Os .Sh NAME .Nm UMA .Nd general-purpose kernel object allocator .Sh SYNOPSIS .In sys/param.h .In sys/queue.h .In vm/uma.h .Cd "options UMA_FIRSTTOUCH" .Cd "options UMA_XDOMAIN" .Bd -literal typedef int (*uma_ctor)(void *mem, int size, void *arg, int flags); typedef void (*uma_dtor)(void *mem, int size, void *arg); typedef int (*uma_init)(void *mem, int size, int flags); typedef void (*uma_fini)(void *mem, int size); typedef int (*uma_import)(void *arg, void **store, int count, int domain, int flags); typedef void (*uma_release)(void *arg, void **store, int count); typedef void *(*uma_alloc)(uma_zone_t zone, vm_size_t size, int domain, uint8_t *pflag, int wait); typedef void (*uma_free)(void *item, vm_size_t size, uint8_t pflag); .Ed .Ft uma_zone_t .Fo uma_zcreate .Fa "char *name" "int size" .Fa "uma_ctor ctor" "uma_dtor dtor" "uma_init zinit" "uma_fini zfini" .Fa "int align" "uint16_t flags" .Fc .Ft uma_zone_t .Fo uma_zcache_create .Fa "char *name" "int size" .Fa "uma_ctor ctor" "uma_dtor dtor" "uma_init zinit" "uma_fini zfini" .Fa "uma_import zimport" "uma_release zrelease" .Fa "void *arg" "int flags" .Fc .Ft uma_zone_t .Fo uma_zsecond_create .Fa "char *name" .Fa "uma_ctor ctor" "uma_dtor dtor" "uma_init zinit" "uma_fini zfini" .Fa "uma_zone_t master" .Fc .Ft void .Fn uma_zdestroy "uma_zone_t zone" .Ft "void *" .Fn uma_zalloc "uma_zone_t zone" "int flags" .Ft "void *" .Fn uma_zalloc_arg "uma_zone_t zone" "void *arg" "int flags" .Ft "void *" .Fn uma_zalloc_domain "uma_zone_t zone" "void *arg" "int domain" "int flags" .Ft "void *" .Fn uma_zalloc_pcpu "uma_zone_t zone" "int flags" .Ft "void *" .Fn uma_zalloc_pcpu_arg "uma_zone_t zone" "void *arg" "int flags" .Ft void .Fn uma_zfree "uma_zone_t zone" "void *item" .Ft void .Fn uma_zfree_arg "uma_zone_t zone" "void *item" "void *arg" .Ft void .Fn uma_zfree_domain "uma_zone_t zone" "void *item" "void *arg" .Ft void .Fn uma_zfree_pcpu "uma_zone_t zone" "void *item" .Ft void .Fn uma_zfree_pcpu_arg "uma_zone_t zone" "void *item" "void *arg" .Ft void .Fn uma_prealloc "uma_zone_t zone" "int nitems" .Ft void .Fn uma_zone_reserve "uma_zone_t zone" "int nitems" .Ft void .Fn uma_zone_reserve_kva "uma_zone_t zone" "int nitems" .Ft void .Fn uma_reclaim "int req" .Ft void .Fn uma_zone_reclaim "uma_zone_t zone" "int req" .Ft void .Fn uma_zone_set_allocf "uma_zone_t zone" "uma_alloc allocf" .Ft void .Fn uma_zone_set_freef "uma_zone_t zone" "uma_free freef" .Ft int .Fn uma_zone_set_max "uma_zone_t zone" "int nitems" -.Ft int +.Ft void .Fn uma_zone_set_maxcache "uma_zone_t zone" "int nitems" .Ft int .Fn uma_zone_get_max "uma_zone_t zone" .Ft int .Fn uma_zone_get_cur "uma_zone_t zone" .Ft void .Fn uma_zone_set_warning "uma_zone_t zone" "const char *warning" .Ft void .Fn uma_zone_set_maxaction "uma_zone_t zone" "void (*maxaction)(uma_zone_t)" .Ft void .Fn uma_reclaim .In sys/sysctl.h .Fn SYSCTL_UMA_MAX parent nbr name access zone descr .Fn SYSCTL_ADD_UMA_MAX ctx parent nbr name access zone descr .Fn SYSCTL_UMA_CUR parent nbr name access zone descr .Fn SYSCTL_ADD_UMA_CUR ctx parent nbr name access zone descr .Sh DESCRIPTION UMA (Universal Memory Allocator) provides an efficient interface for managing dynamically-sized collections of items of identical size, referred to as zones. Zones keep track of which items are in use and which are not, and UMA provides functions for allocating items from a zone and for releasing them back, making them available for subsequent allocation requests. Zones maintain per-CPU caches with linear scalability on SMP systems as well as round-robin and first-touch policies for NUMA systems. The number of items cached per CPU is bounded, and each zone additionally maintains an unbounded cache of items that is used to quickly satisfy per-CPU cache allocation misses. .Pp Two types of zones exist: regular zones and cache zones. In a regular zone, items are allocated from a slab, which is one or more virtually contiguous memory pages that have been allocated from the kernel's page allocator. Internally, slabs are managed by a UMA keg, which is responsible for allocating slabs and keeping track of their usage by one or more zones. In typical usage, there is one keg per zone, so slabs are not shared among multiple zones. .Pp Normal zones import items from a keg, and release items back to that keg if requested. Cache zones do not have a keg, and instead use custom import and release methods. For example, some collections of kernel objects are statically allocated at boot-time, and the size of the collection does not change. A cache zone can be used to implement an efficient allocator for the objects in such a collection. .Pp The .Fn uma_zcreate and .Fn uma_zcache_create functions create a new regular zone and cache zone, respectively. The .Fn uma_zsecond_create function creates a regular zone which shares the keg of the zone specified by the .Fa master argument. The .Fa name argument is a text name of the zone for debugging and stats; this memory should not be freed until the zone has been deallocated. .Pp The .Fa ctor and .Fa dtor arguments are callback functions that are called by the UMA subsystem at the time of the call to .Fn uma_zalloc and .Fn uma_zfree respectively. Their purpose is to provide hooks for initializing or destroying things that need to be done at the time of the allocation or release of a resource. A good usage for the .Fa ctor and .Fa dtor callbacks might be to initialize a data structure embedded in the item, such as a .Xr queue 3 head. .Pp The .Fa zinit and .Fa zfini arguments are used to optimize the allocation of items from the zone. They are called by the UMA subsystem whenever it needs to allocate or free items to satisfy requests or memory pressure. A good use for the .Fa zinit and .Fa zfini callbacks might be to initialize and destroy a mutex contained within an item. This would allow one to avoid destroying and re-initializing the mutex each time the item is freed and re-allocated. They are not called on each call to .Fn uma_zalloc and .Fn uma_zfree but rather when an item is imported into a zone's cache, and when a zone releases an item to the slab allocator, typically as a response to memory pressure. .Pp For .Fn uma_zcache_create , the .Fa zimport and .Fa zrelease functions are called to import items into the zone and to release items from the zone, respectively. The .Fa zimport function should store pointers to items in the .Fa store array, which contains a maximum of .Fa count entries. The function must return the number of imported items, which may be less than the maximum. Similarly, the .Fa store parameter to the .Fa zrelease function contains an array of .Fa count pointers to items. The .Fa arg parameter passed to .Fn uma_zcache_create is provided to the import and release functions. The .Fa domain parameter to .Fa zimport specifies the requested .Xr numa 4 domain for the allocation. It is either a NUMA domain number or the special value .Dv UMA_ANYDOMAIN . .Pp The .Fa flags argument of .Fn uma_zcreate and .Fn uma_zcache_create is a subset of the following flags: .Bl -tag -width "foo" .It Dv UMA_ZONE_NOFREE Slabs allocated to the zone's keg are never freed. .It Dv UMA_ZONE_NODUMP Pages belonging to the zone will not be included in minidumps. .It Dv UMA_ZONE_PCPU An allocation from zone would have .Va mp_ncpu shadow copies, that are privately assigned to CPUs. A CPU can address its private copy using base the allocation address plus a multiple of the current CPU ID and .Fn sizeof "struct pcpu" : .Bd -literal -offset indent foo_zone = uma_zcreate(..., UMA_ZONE_PCPU); ... foo_base = uma_zalloc(foo_zone, ...); ... critical_enter(); foo_pcpu = (foo_t *)zpcpu_get(foo_base); /* do something with foo_pcpu */ critical_exit(); .Ed Note that .Dv M_ZERO cannot be used when allocating items from a PCPU zone. To obtain zeroed memory from a PCPU zone, use the .Fn uma_zalloc_pcpu function and its variants instead, and pass .Dv M_ZERO . .It Dv UMA_ZONE_OFFPAGE By default book-keeping of items within a slab is done in the slab page itself. This flag explicitly tells subsystem that book-keeping structure should be allocated separately from special internal zone. This flag requires either .Dv UMA_ZONE_VTOSLAB or .Dv UMA_ZONE_HASH , since subsystem requires a mechanism to find a book-keeping structure to an item being freed. The subsystem may choose to prefer offpage book-keeping for certain zones implicitly. .It Dv UMA_ZONE_ZINIT The zone will have its .Ft uma_init method set to internal method that initializes a new allocated slab to all zeros. Do not mistake .Ft uma_init method with .Ft uma_ctor . A zone with .Dv UMA_ZONE_ZINIT flag would not return zeroed memory on every .Fn uma_zalloc . .It Dv UMA_ZONE_HASH The zone should use an internal hash table to find slab book-keeping structure where an allocation being freed belongs to. .It Dv UMA_ZONE_VTOSLAB The zone should use special field of .Vt vm_page_t to find slab book-keeping structure where an allocation being freed belongs to. .It Dv UMA_ZONE_MALLOC The zone is for the .Xr malloc 9 subsystem. .It Dv UMA_ZONE_VM The zone is for the VM subsystem. .It Dv UMA_ZONE_NUMA The zone should use a first-touch NUMA policy rather than the round-robin default. If the .Dv UMA_FIRSTTOUCH kernel option is configured, all zones implicitly use a first-touch policy, and the .Dv UMA_ZONE_NUMA flag has no effect. The .Dv UMA_XDOMAIN kernel option, when configured, causes UMA to do the extra tracking to ensure that allocations from first-touch zones are always local. Otherwise, consumers that do not free memory on the same domain from which it was allocated will cause mixing in per-CPU caches. See .Xr numa 4 for more details. .El .Pp Zones can be destroyed using .Fn uma_zdestroy , freeing all memory that is cached in the zone. All items allocated from the zone must be freed to the zone before the zone may be safely destroyed. .Pp To allocate an item from a zone, simply call .Fn uma_zalloc with a pointer to that zone and set the .Fa flags argument to selected flags as documented in .Xr malloc 9 . It will return a pointer to an item if successful, or .Dv NULL in the rare case where all items in the zone are in use and the allocator is unable to grow the zone and .Dv M_NOWAIT is specified. .Pp Items are released back to the zone from which they were allocated by calling .Fn uma_zfree with a pointer to the zone and a pointer to the item. If .Fa item is .Dv NULL , then .Fn uma_zfree does nothing. .Pp The variants .Fn uma_zalloc_arg and .Fn uma_zfree_arg allow callers to specify an argument for the .Dv ctor and .Dv dtor functions of the zone, respectively. The .Fn uma_zalloc_domain function allows callers to specify a fixed .Xr numa 4 domain to allocate from. This uses a guaranteed but slow path in the allocator which reduces concurrency. The .Fn uma_zfree_domain function should be used to return memory allocated in this fashion. This function infers the domain from the pointer and does not require it as an argument. .Pp The .Fn uma_zone_prealloc function allocates slabs for the requested number of items, typically following the initial creation of a zone. Subsequent allocations from the zone will be satisfied using the pre-allocated slabs. Note that slab allocation is performed with the .Dv M_WAITOK flag, so .Fn uma_zone_prealloc may sleep. .Pp The .Fn uma_zone_reserve function sets the number of reserved items for the zone. .Fn uma_zalloc and variants will ensure that the zone contains at least the reserved number of free items. Reserved items may be allocated by specifying .Dv M_USE_RESERVE in the allocation request flags. .Fn uma_zone_reserve does not perform any pre-allocation by itself. .Pp The .Fn uma_zone_reserve_kva function pre-allocates kernel virtual address space for the requested number of items. Subsequent allocations from the zone will be satisfied using the pre-allocated address space. Note that unlike .Fn uma_zone_reserve , .Fn uma_zone_reserve_kva does not restrict the use of the pre-allocation to .Dv M_USE_RESERVE requests. .Pp The .Fn uma_reclaim and .Fn uma_zone_reclaim functions reclaim cached items from UMA zones, releasing unused memory. The .Fn uma_reclaim function reclaims items from all regular zones, while .Fn uma_zone_reclaim reclaims items only from the specified zone. The .Fa req parameter must be one of three values which specify how aggressively items are to be reclaimed: .Bl -tag -width indent .It Dv UMA_RECLAIM_TRIM Reclaim items only in excess of the zone's estimated working set size. The working set size is periodically updated and tracks the recent history of the zone's usage. .It Dv UMA_RECLAIM_DRAIN Reclaim all items from the unbounded cache. Free items in the per-CPU caches are left alone. .It Dv UMA_RECLAIM_DRAIN_CPU Reclaim all cached items. .El .Pp The .Fn uma_zone_set_allocf and .Fn uma_zone_set_freef functions allow a zone's default slab allocation and free functions to be overridden. This is useful if the zone's items have special memory allocation constraints. For example, if multi-page objects are required to be physically contiguous, an .Fa allocf function which requests contiguous memory from the kernel's page allocator may be used. .Pp The .Fn uma_zone_set_max function limits the number of items .Pq and therefore memory that can be allocated to .Fa zone . The .Fa nitems argument specifies the requested upper limit number of items. The effective limit is returned to the caller, as it may end up being higher than requested due to the implementation rounding up to ensure all memory pages allocated to the zone are utilised to capacity. The limit applies to the total number of items in the zone, which includes allocated items, free items and free items in the per-cpu caches. On systems with more than one CPU it may not be possible to allocate the specified number of items even when there is no shortage of memory, because all of the remaining free items may be in the caches of the other CPUs when the limit is hit. .Pp The .Fn uma_zone_set_maxcache -function limits the number of free items which may be cached in the zone, -excluding the per-CPU caches, which are bounded in size. -For example, to implement a -.Ql pure -per-CPU cache, a cache zone may be configured with a maximum cache size of 0. +function limits the number of free items which may be cached in the zone. +This limit applies to both the per-CPU caches and the cache of free buckets. .Pp The .Fn uma_zone_get_max function returns the effective upper limit number of items for a zone. .Pp The .Fn uma_zone_get_cur function returns an approximation of the number of items currently allocated from the zone. The returned value is approximate because appropriate synchronisation to determine an exact value is not performed by the implementation. This ensures low overhead at the expense of potentially stale data being used in the calculation. .Pp The .Fn uma_zone_set_warning function sets a warning that will be printed on the system console when the given zone becomes full and fails to allocate an item. The warning will be printed no more often than every five minutes. Warnings can be turned off globally by setting the .Va vm.zone_warnings sysctl tunable to .Va 0 . .Pp The .Fn uma_zone_set_maxaction function sets a function that will be called when the given zone becomes full and fails to allocate an item. The function will be called with the zone locked. Also, the function that called the allocation function may have held additional locks. Therefore, this function should do very little work (similar to a signal handler). .Pp The .Fn SYSCTL_UMA_MAX parent nbr name access zone descr macro declares a static .Xr sysctl 9 oid that exports the effective upper limit number of items for a zone. The .Fa zone argument should be a pointer to .Vt uma_zone_t . A read of the oid returns value obtained through .Fn uma_zone_get_max . A write to the oid sets new value via .Fn uma_zone_set_max . The .Fn SYSCTL_ADD_UMA_MAX ctx parent nbr name access zone descr macro is provided to create this type of oid dynamically. .Pp The .Fn SYSCTL_UMA_CUR parent nbr name access zone descr macro declares a static read-only .Xr sysctl 9 oid that exports the approximate current occupancy of the zone. The .Fa zone argument should be a pointer to .Vt uma_zone_t . A read of the oid returns value obtained through .Fn uma_zone_get_cur . The .Fn SYSCTL_ADD_UMA_CUR ctx parent nbr name zone descr macro is provided to create this type of oid dynamically. .Sh IMPLEMENTATION NOTES The memory that these allocation calls return is not executable. The .Fn uma_zalloc function does not support the .Dv M_EXEC flag to allocate executable memory. Not all platforms enforce a distinction between executable and non-executable memory. .Sh SEE ALSO .Xr numa 4 , .Xr vmstat 8 , .Xr malloc 9 .Rs .%A Jeff Bonwick .%T "The Slab Allocator: An Object-Caching Kernel Memory Allocator" .%D 1994 .Re .Sh HISTORY The zone allocator first appeared in .Fx 3.0 . It was radically changed in .Fx 5.0 to function as a slab allocator. .Sh AUTHORS .An -nosplit The zone allocator was written by .An John S. Dyson . The zone allocator was rewritten in large parts by .An Jeff Roberson Aq Mt jeff@FreeBSD.org to function as a slab allocator. .Pp This manual page was written by .An Dag-Erling Sm\(/orgrav Aq Mt des@FreeBSD.org . Changes for UMA by .An Jeroen Ruigrok van der Werven Aq Mt asmodai@FreeBSD.org . Index: head/sys/vm/uma.h =================================================================== --- head/sys/vm/uma.h (revision 355001) +++ head/sys/vm/uma.h (revision 355002) @@ -1,716 +1,713 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2002, 2003, 2004, 2005 Jeffrey Roberson * Copyright (c) 2004, 2005 Bosko Milekic * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice unmodified, this list of conditions, and the following * disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * $FreeBSD$ * */ /* * uma.h - External definitions for the Universal Memory Allocator * */ #ifndef _VM_UMA_H_ #define _VM_UMA_H_ #include /* For NULL */ #include /* For M_* */ /* User visible parameters */ #define UMA_SMALLEST_UNIT (PAGE_SIZE / 256) /* Smallest item allocated */ /* Types and type defs */ struct uma_zone; /* Opaque type used as a handle to the zone */ typedef struct uma_zone * uma_zone_t; /* * Item constructor * * Arguments: * item A pointer to the memory which has been allocated. * arg The arg field passed to uma_zalloc_arg * size The size of the allocated item * flags See zalloc flags * * Returns: * 0 on success * errno on failure * * Discussion: * The constructor is called just before the memory is returned * to the user. It may block if necessary. */ typedef int (*uma_ctor)(void *mem, int size, void *arg, int flags); /* * Item destructor * * Arguments: * item A pointer to the memory which has been allocated. * size The size of the item being destructed. * arg Argument passed through uma_zfree_arg * * Returns: * Nothing * * Discussion: * The destructor may perform operations that differ from those performed * by the initializer, but it must leave the object in the same state. * This IS type stable storage. This is called after EVERY zfree call. */ typedef void (*uma_dtor)(void *mem, int size, void *arg); /* * Item initializer * * Arguments: * item A pointer to the memory which has been allocated. * size The size of the item being initialized. * flags See zalloc flags * * Returns: * 0 on success * errno on failure * * Discussion: * The initializer is called when the memory is cached in the uma zone. * The initializer and the destructor should leave the object in the same * state. */ typedef int (*uma_init)(void *mem, int size, int flags); /* * Item discard function * * Arguments: * item A pointer to memory which has been 'freed' but has not left the * zone's cache. * size The size of the item being discarded. * * Returns: * Nothing * * Discussion: * This routine is called when memory leaves a zone and is returned to the * system for other uses. It is the counter-part to the init function. */ typedef void (*uma_fini)(void *mem, int size); /* * Import new memory into a cache zone. */ typedef int (*uma_import)(void *arg, void **store, int count, int domain, int flags); /* * Free memory from a cache zone. */ typedef void (*uma_release)(void *arg, void **store, int count); /* * What's the difference between initializing and constructing? * * The item is initialized when it is cached, and this is the state that the * object should be in when returned to the allocator. The purpose of this is * to remove some code which would otherwise be called on each allocation by * utilizing a known, stable state. This differs from the constructor which * will be called on EVERY allocation. * * For example, in the initializer you may want to initialize embedded locks, * NULL list pointers, set up initial states, magic numbers, etc. This way if * the object is held in the allocator and re-used it won't be necessary to * re-initialize it. * * The constructor may be used to lock a data structure, link it on to lists, * bump reference counts or total counts of outstanding structures, etc. * */ /* Function proto types */ /* * Create a new uma zone * * Arguments: * name The text name of the zone for debugging and stats. This memory * should not be freed until the zone has been deallocated. * size The size of the object that is being created. * ctor The constructor that is called when the object is allocated. * dtor The destructor that is called when the object is freed. * init An initializer that sets up the initial state of the memory. * fini A discard function that undoes initialization done by init. * ctor/dtor/init/fini may all be null, see notes above. * align A bitmask that corresponds to the requested alignment * eg 4 would be 0x3 * flags A set of parameters that control the behavior of the zone. * * Returns: * A pointer to a structure which is intended to be opaque to users of * the interface. The value may be null if the wait flag is not set. */ uma_zone_t uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor, uma_init uminit, uma_fini fini, int align, uint32_t flags); /* * Create a secondary uma zone * * Arguments: * name The text name of the zone for debugging and stats. This memory * should not be freed until the zone has been deallocated. * ctor The constructor that is called when the object is allocated. * dtor The destructor that is called when the object is freed. * zinit An initializer that sets up the initial state of the memory * as the object passes from the Keg's slab to the Zone's cache. * zfini A discard function that undoes initialization done by init * as the object passes from the Zone's cache to the Keg's slab. * * ctor/dtor/zinit/zfini may all be null, see notes above. * Note that the zinit and zfini specified here are NOT * exactly the same as the init/fini specified to uma_zcreate() * when creating a master zone. These zinit/zfini are called * on the TRANSITION from keg to zone (and vice-versa). Once * these are set, the primary zone may alter its init/fini * (which are called when the object passes from VM to keg) * using uma_zone_set_init/fini()) as well as its own * zinit/zfini (unset by default for master zone) with * uma_zone_set_zinit/zfini() (note subtle 'z' prefix). * * master A reference to this zone's Master Zone (Primary Zone), * which contains the backing Keg for the Secondary Zone * being added. * * Returns: * A pointer to a structure which is intended to be opaque to users of * the interface. The value may be null if the wait flag is not set. */ uma_zone_t uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor, uma_init zinit, uma_fini zfini, uma_zone_t master); /* * Create cache-only zones. * * This allows uma's per-cpu cache facilities to handle arbitrary * pointers. Consumers must specify the import and release functions to * fill and destroy caches. UMA does not allocate any memory for these * zones. The 'arg' parameter is passed to import/release and is caller * specific. */ uma_zone_t uma_zcache_create(char *name, int size, uma_ctor ctor, uma_dtor dtor, uma_init zinit, uma_fini zfini, uma_import zimport, uma_release zrelease, void *arg, int flags); /* * Definitions for uma_zcreate flags * * These flags share space with UMA_ZFLAGs in uma_int.h. Be careful not to * overlap when adding new features. 0xff000000 is in use by uma_int.h. */ #define UMA_ZONE_PAGEABLE 0x0001 /* Return items not fully backed by physical memory XXX Not yet */ #define UMA_ZONE_ZINIT 0x0002 /* Initialize with zeros */ #define UMA_ZONE_STATIC 0x0004 /* Statically sized zone */ #define UMA_ZONE_OFFPAGE 0x0008 /* Force the slab structure allocation off of the real memory */ #define UMA_ZONE_MALLOC 0x0010 /* For use by malloc(9) only! */ #define UMA_ZONE_NOFREE 0x0020 /* Do not free slabs of this type! */ #define UMA_ZONE_MTXCLASS 0x0040 /* Create a new lock class */ #define UMA_ZONE_VM 0x0080 /* * Used for internal vm datastructures * only. */ #define UMA_ZONE_HASH 0x0100 /* * Use a hash table instead of caching * information in the vm_page. */ #define UMA_ZONE_SECONDARY 0x0200 /* Zone is a Secondary Zone */ #define UMA_ZONE_NOBUCKET 0x0400 /* Do not use buckets. */ #define UMA_ZONE_MAXBUCKET 0x0800 /* Use largest buckets. */ #define UMA_ZONE_CACHESPREAD 0x1000 /* * Spread memory start locations across * all possible cache lines. May * require many virtually contiguous * backend pages and can fail early. */ #define UMA_ZONE_VTOSLAB 0x2000 /* Zone uses vtoslab for lookup. */ #define UMA_ZONE_NODUMP 0x4000 /* * Zone's pages will not be included in * mini-dumps. */ #define UMA_ZONE_PCPU 0x8000 /* * Allocates mp_maxid + 1 slabs of PAGE_SIZE */ #define UMA_ZONE_NUMA 0x10000 /* * NUMA aware Zone. Implements a best * effort first-touch policy. */ #define UMA_ZONE_MINBUCKET 0x20000 /* Use smallest buckets. */ /* * These flags are shared between the keg and zone. In zones wishing to add * new kegs these flags must be compatible. Some are determined based on * physical parameters of the request and may not be provided by the consumer. */ #define UMA_ZONE_INHERIT \ (UMA_ZONE_OFFPAGE | UMA_ZONE_MALLOC | UMA_ZONE_NOFREE | \ UMA_ZONE_HASH | UMA_ZONE_VTOSLAB | UMA_ZONE_PCPU | UMA_ZONE_NUMA) /* Definitions for align */ #define UMA_ALIGN_PTR (sizeof(void *) - 1) /* Alignment fit for ptr */ #define UMA_ALIGN_LONG (sizeof(long) - 1) /* "" long */ #define UMA_ALIGN_INT (sizeof(int) - 1) /* "" int */ #define UMA_ALIGN_SHORT (sizeof(short) - 1) /* "" short */ #define UMA_ALIGN_CHAR (sizeof(char) - 1) /* "" char */ #define UMA_ALIGN_CACHE (0 - 1) /* Cache line size align */ #define UMA_ALIGNOF(type) (_Alignof(type) - 1) /* Alignment fit for 'type' */ #define UMA_ANYDOMAIN -1 /* Special value for domain search. */ /* * Destroys an empty uma zone. If the zone is not empty uma complains loudly. * * Arguments: * zone The zone we want to destroy. * */ void uma_zdestroy(uma_zone_t zone); /* * Allocates an item out of a zone * * Arguments: * zone The zone we are allocating from * arg This data is passed to the ctor function * flags See sys/malloc.h for available flags. * * Returns: * A non-null pointer to an initialized element from the zone is * guaranteed if the wait flag is M_WAITOK. Otherwise a null pointer * may be returned if the zone is empty or the ctor failed. */ void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags); void *uma_zalloc_pcpu_arg(uma_zone_t zone, void *arg, int flags); /* * Allocate an item from a specific NUMA domain. This uses a slow path in * the allocator but is guaranteed to allocate memory from the requested * domain if M_WAITOK is set. * * Arguments: * zone The zone we are allocating from * arg This data is passed to the ctor function * domain The domain to allocate from. * flags See sys/malloc.h for available flags. */ void *uma_zalloc_domain(uma_zone_t zone, void *arg, int domain, int flags); /* * Allocates an item out of a zone without supplying an argument * * This is just a wrapper for uma_zalloc_arg for convenience. * */ static __inline void *uma_zalloc(uma_zone_t zone, int flags); static __inline void *uma_zalloc_pcpu(uma_zone_t zone, int flags); static __inline void * uma_zalloc(uma_zone_t zone, int flags) { return uma_zalloc_arg(zone, NULL, flags); } static __inline void * uma_zalloc_pcpu(uma_zone_t zone, int flags) { return uma_zalloc_pcpu_arg(zone, NULL, flags); } /* * Frees an item back into the specified zone. * * Arguments: * zone The zone the item was originally allocated out of. * item The memory to be freed. * arg Argument passed to the destructor * * Returns: * Nothing. */ void uma_zfree_arg(uma_zone_t zone, void *item, void *arg); void uma_zfree_pcpu_arg(uma_zone_t zone, void *item, void *arg); /* * Frees an item back to the specified zone's domain specific pool. * * Arguments: * zone The zone the item was originally allocated out of. * item The memory to be freed. * arg Argument passed to the destructor */ void uma_zfree_domain(uma_zone_t zone, void *item, void *arg); /* * Frees an item back to a zone without supplying an argument * * This is just a wrapper for uma_zfree_arg for convenience. * */ static __inline void uma_zfree(uma_zone_t zone, void *item); static __inline void uma_zfree_pcpu(uma_zone_t zone, void *item); static __inline void uma_zfree(uma_zone_t zone, void *item) { uma_zfree_arg(zone, item, NULL); } static __inline void uma_zfree_pcpu(uma_zone_t zone, void *item) { uma_zfree_pcpu_arg(zone, item, NULL); } /* * Wait until the specified zone can allocate an item. */ void uma_zwait(uma_zone_t zone); /* * Backend page supplier routines * * Arguments: * zone The zone that is requesting pages. * size The number of bytes being requested. * pflag Flags for these memory pages, see below. * domain The NUMA domain that we prefer for this allocation. * wait Indicates our willingness to block. * * Returns: * A pointer to the allocated memory or NULL on failure. */ typedef void *(*uma_alloc)(uma_zone_t zone, vm_size_t size, int domain, uint8_t *pflag, int wait); /* * Backend page free routines * * Arguments: * item A pointer to the previously allocated pages. * size The original size of the allocation. * pflag The flags for the slab. See UMA_SLAB_* below. * * Returns: * None */ typedef void (*uma_free)(void *item, vm_size_t size, uint8_t pflag); /* * Reclaims unused memory * * Arguments: * req Reclamation request type. * Returns: * None */ #define UMA_RECLAIM_DRAIN 1 /* release bucket cache */ #define UMA_RECLAIM_DRAIN_CPU 2 /* release bucket and per-CPU caches */ #define UMA_RECLAIM_TRIM 3 /* trim bucket cache to WSS */ void uma_reclaim(int req); void uma_zone_reclaim(uma_zone_t, int req); /* * Sets the alignment mask to be used for all zones requesting cache * alignment. Should be called by MD boot code prior to starting VM/UMA. * * Arguments: * align The alignment mask * * Returns: * Nothing */ void uma_set_align(int align); /* * Set a reserved number of items to hold for M_USE_RESERVE allocations. All * other requests must allocate new backing pages. */ void uma_zone_reserve(uma_zone_t zone, int nitems); /* * Reserves the maximum KVA space required by the zone and configures the zone * to use a VM_ALLOC_NOOBJ-based backend allocator. * * Arguments: * zone The zone to update. * nitems The upper limit on the number of items that can be allocated. * * Returns: * 0 if KVA space can not be allocated * 1 if successful * * Discussion: * When the machine supports a direct map and the zone's items are smaller * than a page, the zone will use the direct map instead of allocating KVA * space. */ int uma_zone_reserve_kva(uma_zone_t zone, int nitems); /* * Sets a high limit on the number of items allowed in a zone * * Arguments: * zone The zone to limit * nitems The requested upper limit on the number of items allowed * * Returns: - * int The effective value of nitems after rounding up based on page size + * int The effective value of nitems */ int uma_zone_set_max(uma_zone_t zone, int nitems); /* * Sets a high limit on the number of items allowed in zone's bucket cache * * Arguments: * zone The zone to limit * nitems The requested upper limit on the number of items allowed - * - * Returns: - * int The effective value of nitems set */ -int uma_zone_set_maxcache(uma_zone_t zone, int nitems); +void uma_zone_set_maxcache(uma_zone_t zone, int nitems); /* * Obtains the effective limit on the number of items in a zone * * Arguments: * zone The zone to obtain the effective limit from * * Return: * 0 No limit * int The effective limit of the zone */ int uma_zone_get_max(uma_zone_t zone); /* * Sets a warning to be printed when limit is reached * * Arguments: * zone The zone we will warn about * warning Warning content * * Returns: * Nothing */ void uma_zone_set_warning(uma_zone_t zone, const char *warning); /* * Sets a function to run when limit is reached * * Arguments: * zone The zone to which this applies * fx The function ro run * * Returns: * Nothing */ typedef void (*uma_maxaction_t)(uma_zone_t, int); void uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t); /* * Obtains the approximate current number of items allocated from a zone * * Arguments: * zone The zone to obtain the current allocation count from * * Return: * int The approximate current number of items allocated from the zone */ int uma_zone_get_cur(uma_zone_t zone); /* * The following two routines (uma_zone_set_init/fini) * are used to set the backend init/fini pair which acts on an * object as it becomes allocated and is placed in a slab within * the specified zone's backing keg. These should probably not * be changed once allocations have already begun, but only be set * immediately upon zone creation. */ void uma_zone_set_init(uma_zone_t zone, uma_init uminit); void uma_zone_set_fini(uma_zone_t zone, uma_fini fini); /* * The following two routines (uma_zone_set_zinit/zfini) are * used to set the zinit/zfini pair which acts on an object as * it passes from the backing Keg's slab cache to the * specified Zone's bucket cache. These should probably not * be changed once allocations have already begun, but only be set * immediately upon zone creation. */ void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit); void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini); /* * Replaces the standard backend allocator for this zone. * * Arguments: * zone The zone whose backend allocator is being changed. * allocf A pointer to the allocation function * * Returns: * Nothing * * Discussion: * This could be used to implement pageable allocation, or perhaps * even DMA allocators if used in conjunction with the OFFPAGE * zone flag. */ void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf); /* * Used for freeing memory provided by the allocf above * * Arguments: * zone The zone that intends to use this free routine. * freef The page freeing routine. * * Returns: * Nothing */ void uma_zone_set_freef(uma_zone_t zone, uma_free freef); /* * These flags are setable in the allocf and visible in the freef. */ #define UMA_SLAB_BOOT 0x01 /* Slab alloced from boot pages */ #define UMA_SLAB_KERNEL 0x04 /* Slab alloced from kmem */ #define UMA_SLAB_PRIV 0x08 /* Slab alloced from priv allocator */ #define UMA_SLAB_OFFP 0x10 /* Slab is managed separately */ #define UMA_SLAB_MALLOC 0x20 /* Slab is a large malloc slab */ /* 0x02, 0x40, and 0x80 are available */ /* * Used to pre-fill a zone with some number of items * * Arguments: * zone The zone to fill * itemcnt The number of items to reserve * * Returns: * Nothing * * NOTE: This is blocking and should only be done at startup */ void uma_prealloc(uma_zone_t zone, int itemcnt); /* * Used to determine if a fixed-size zone is exhausted. * * Arguments: * zone The zone to check * * Returns: * Non-zero if zone is exhausted. */ int uma_zone_exhausted(uma_zone_t zone); int uma_zone_exhausted_nolock(uma_zone_t zone); /* * Common UMA_ZONE_PCPU zones. */ extern uma_zone_t pcpu_zone_int; extern uma_zone_t pcpu_zone_64; /* * Exported statistics structures to be used by user space monitoring tools. * Statistics stream consists of a uma_stream_header, followed by a series of * alternative uma_type_header and uma_type_stat structures. */ #define UMA_STREAM_VERSION 0x00000001 struct uma_stream_header { uint32_t ush_version; /* Stream format version. */ uint32_t ush_maxcpus; /* Value of MAXCPU for stream. */ uint32_t ush_count; /* Number of records. */ uint32_t _ush_pad; /* Pad/reserved field. */ }; #define UTH_MAX_NAME 32 #define UTH_ZONE_SECONDARY 0x00000001 struct uma_type_header { /* * Static per-zone data, some extracted from the supporting keg. */ char uth_name[UTH_MAX_NAME]; uint32_t uth_align; /* Keg: alignment. */ uint32_t uth_size; /* Keg: requested size of item. */ uint32_t uth_rsize; /* Keg: real size of item. */ uint32_t uth_maxpages; /* Keg: maximum number of pages. */ uint32_t uth_limit; /* Keg: max items to allocate. */ /* * Current dynamic zone/keg-derived statistics. */ uint32_t uth_pages; /* Keg: pages allocated. */ uint32_t uth_keg_free; /* Keg: items free. */ uint32_t uth_zone_free; /* Zone: items free. */ uint32_t uth_bucketsize; /* Zone: desired bucket size. */ uint32_t uth_zone_flags; /* Zone: flags. */ uint64_t uth_allocs; /* Zone: number of allocations. */ uint64_t uth_frees; /* Zone: number of frees. */ uint64_t uth_fails; /* Zone: number of alloc failures. */ uint64_t uth_sleeps; /* Zone: number of alloc sleeps. */ uint64_t uth_xdomain; /* Zone: Number of cross domain frees. */ uint64_t _uth_reserved1[1]; /* Reserved. */ }; struct uma_percpu_stat { uint64_t ups_allocs; /* Cache: number of allocations. */ uint64_t ups_frees; /* Cache: number of frees. */ uint64_t ups_cache_free; /* Cache: free items in cache. */ uint64_t _ups_reserved[5]; /* Reserved. */ }; void uma_reclaim_wakeup(void); void uma_reclaim_worker(void *); unsigned long uma_limit(void); /* Return the amount of memory managed by UMA. */ unsigned long uma_size(void); /* Return the amount of memory remaining. May be negative. */ long uma_avail(void); #endif /* _VM_UMA_H_ */ Index: head/sys/vm/uma_core.c =================================================================== --- head/sys/vm/uma_core.c (revision 355001) +++ head/sys/vm/uma_core.c (revision 355002) @@ -1,4479 +1,4507 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2002-2005, 2009, 2013 Jeffrey Roberson * Copyright (c) 2004, 2005 Bosko Milekic * Copyright (c) 2004-2006 Robert N. M. Watson * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice unmodified, this list of conditions, and the following * disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* * uma_core.c Implementation of the Universal Memory allocator * * This allocator is intended to replace the multitude of similar object caches * in the standard FreeBSD kernel. The intent is to be flexible as well as * efficient. A primary design goal is to return unused memory to the rest of * the system. This will make the system as a whole more flexible due to the * ability to move memory to subsystems which most need it instead of leaving * pools of reserved memory unused. * * The basic ideas stem from similar slab/zone based allocators whose algorithms * are well known. * */ /* * TODO: * - Improve memory usage for large allocations * - Investigate cache size adjustments */ #include __FBSDID("$FreeBSD$"); #include "opt_ddb.h" #include "opt_param.h" #include "opt_vm.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef DEBUG_MEMGUARD #include #endif /* * This is the zone and keg from which all zones are spawned. */ static uma_zone_t kegs; static uma_zone_t zones; /* This is the zone from which all offpage uma_slab_ts are allocated. */ static uma_zone_t slabzone; /* * The initial hash tables come out of this zone so they can be allocated * prior to malloc coming up. */ static uma_zone_t hashzone; /* The boot-time adjusted value for cache line alignment. */ int uma_align_cache = 64 - 1; static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets"); /* * Are we allowed to allocate buckets? */ static int bucketdisable = 1; /* Linked list of all kegs in the system */ static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs); /* Linked list of all cache-only zones in the system */ static LIST_HEAD(,uma_zone) uma_cachezones = LIST_HEAD_INITIALIZER(uma_cachezones); /* This RW lock protects the keg list */ static struct rwlock_padalign __exclusive_cache_line uma_rwlock; /* * Pointer and counter to pool of pages, that is preallocated at * startup to bootstrap UMA. */ static char *bootmem; static int boot_pages; static struct sx uma_reclaim_lock; /* * kmem soft limit, initialized by uma_set_limit(). Ensure that early * allocations don't trigger a wakeup of the reclaim thread. */ static unsigned long uma_kmem_limit = LONG_MAX; SYSCTL_ULONG(_vm, OID_AUTO, uma_kmem_limit, CTLFLAG_RD, &uma_kmem_limit, 0, "UMA kernel memory soft limit"); static unsigned long uma_kmem_total; SYSCTL_ULONG(_vm, OID_AUTO, uma_kmem_total, CTLFLAG_RD, &uma_kmem_total, 0, "UMA kernel memory usage"); /* Is the VM done starting up? */ static enum { BOOT_COLD = 0, BOOT_STRAPPED, BOOT_PAGEALLOC, BOOT_BUCKETS, BOOT_RUNNING } booted = BOOT_COLD; /* * This is the handle used to schedule events that need to happen * outside of the allocation fast path. */ static struct callout uma_callout; #define UMA_TIMEOUT 20 /* Seconds for callout interval. */ /* * This structure is passed as the zone ctor arg so that I don't have to create * a special allocation function just for zones. */ struct uma_zctor_args { const char *name; size_t size; uma_ctor ctor; uma_dtor dtor; uma_init uminit; uma_fini fini; uma_import import; uma_release release; void *arg; uma_keg_t keg; int align; uint32_t flags; }; struct uma_kctor_args { uma_zone_t zone; size_t size; uma_init uminit; uma_fini fini; int align; uint32_t flags; }; struct uma_bucket_zone { uma_zone_t ubz_zone; char *ubz_name; int ubz_entries; /* Number of items it can hold. */ int ubz_maxsize; /* Maximum allocation size per-item. */ }; /* * Compute the actual number of bucket entries to pack them in power * of two sizes for more efficient space utilization. */ #define BUCKET_SIZE(n) \ (((sizeof(void *) * (n)) - sizeof(struct uma_bucket)) / sizeof(void *)) #define BUCKET_MAX BUCKET_SIZE(256) #define BUCKET_MIN BUCKET_SIZE(4) struct uma_bucket_zone bucket_zones[] = { { NULL, "4 Bucket", BUCKET_SIZE(4), 4096 }, { NULL, "6 Bucket", BUCKET_SIZE(6), 3072 }, { NULL, "8 Bucket", BUCKET_SIZE(8), 2048 }, { NULL, "12 Bucket", BUCKET_SIZE(12), 1536 }, { NULL, "16 Bucket", BUCKET_SIZE(16), 1024 }, { NULL, "32 Bucket", BUCKET_SIZE(32), 512 }, { NULL, "64 Bucket", BUCKET_SIZE(64), 256 }, { NULL, "128 Bucket", BUCKET_SIZE(128), 128 }, { NULL, "256 Bucket", BUCKET_SIZE(256), 64 }, { NULL, NULL, 0} }; /* * Flags and enumerations to be passed to internal functions. */ enum zfreeskip { SKIP_NONE = 0, SKIP_CNT = 0x00000001, SKIP_DTOR = 0x00010000, SKIP_FINI = 0x00020000, }; /* Prototypes.. */ int uma_startup_count(int); void uma_startup(void *, int); void uma_startup1(void); void uma_startup2(void); static void *noobj_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int); static void *page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int); static void *pcpu_page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int); static void *startup_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int); static void page_free(void *, vm_size_t, uint8_t); static void pcpu_page_free(void *, vm_size_t, uint8_t); static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int, int, int); static void cache_drain(uma_zone_t); static void bucket_drain(uma_zone_t, uma_bucket_t); static void bucket_cache_reclaim(uma_zone_t zone, bool); static int keg_ctor(void *, int, void *, int); static void keg_dtor(void *, int, void *); static int zone_ctor(void *, int, void *, int); static void zone_dtor(void *, int, void *); static int zero_init(void *, int, int); static void keg_small_init(uma_keg_t keg); static void keg_large_init(uma_keg_t keg); static void zone_foreach(void (*zfunc)(uma_zone_t)); static void zone_timeout(uma_zone_t zone); static int hash_alloc(struct uma_hash *, u_int); static int hash_expand(struct uma_hash *, struct uma_hash *); static void hash_free(struct uma_hash *hash); static void uma_timeout(void *); static void uma_startup3(void); static void *zone_alloc_item(uma_zone_t, void *, int, int); static void *zone_alloc_item_locked(uma_zone_t, void *, int, int); static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip); static void bucket_enable(void); static void bucket_init(void); static uma_bucket_t bucket_alloc(uma_zone_t zone, void *, int); static void bucket_free(uma_zone_t zone, uma_bucket_t, void *); static void bucket_zone_drain(void); static uma_bucket_t zone_alloc_bucket(uma_zone_t, void *, int, int, int); static uma_slab_t zone_fetch_slab(uma_zone_t, uma_keg_t, int, int); static void *slab_alloc_item(uma_keg_t keg, uma_slab_t slab); static void slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item); static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini, int align, uint32_t flags); static int zone_import(uma_zone_t, void **, int, int, int); static void zone_release(uma_zone_t, void **, int); static void uma_zero_item(void *, uma_zone_t); void uma_print_zone(uma_zone_t); void uma_print_stats(void); static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS); static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS); #ifdef INVARIANTS static bool uma_dbg_kskip(uma_keg_t keg, void *mem); static bool uma_dbg_zskip(uma_zone_t zone, void *mem); static void uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item); static void uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item); static SYSCTL_NODE(_vm, OID_AUTO, debug, CTLFLAG_RD, 0, "Memory allocation debugging"); static u_int dbg_divisor = 1; SYSCTL_UINT(_vm_debug, OID_AUTO, divisor, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &dbg_divisor, 0, "Debug & thrash every this item in memory allocator"); static counter_u64_t uma_dbg_cnt = EARLY_COUNTER; static counter_u64_t uma_skip_cnt = EARLY_COUNTER; SYSCTL_COUNTER_U64(_vm_debug, OID_AUTO, trashed, CTLFLAG_RD, &uma_dbg_cnt, "memory items debugged"); SYSCTL_COUNTER_U64(_vm_debug, OID_AUTO, skipped, CTLFLAG_RD, &uma_skip_cnt, "memory items skipped, not debugged"); #endif SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL); SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLTYPE_INT, 0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones"); SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLTYPE_STRUCT, 0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats"); static int zone_warnings = 1; SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RWTUN, &zone_warnings, 0, "Warn when UMA zones becomes full"); /* Adjust bytes under management by UMA. */ static inline void uma_total_dec(unsigned long size) { atomic_subtract_long(&uma_kmem_total, size); } static inline void uma_total_inc(unsigned long size) { if (atomic_fetchadd_long(&uma_kmem_total, size) > uma_kmem_limit) uma_reclaim_wakeup(); } /* * This routine checks to see whether or not it's safe to enable buckets. */ static void bucket_enable(void) { bucketdisable = vm_page_count_min(); } /* * Initialize bucket_zones, the array of zones of buckets of various sizes. * * For each zone, calculate the memory required for each bucket, consisting * of the header and an array of pointers. */ static void bucket_init(void) { struct uma_bucket_zone *ubz; int size; for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) { size = roundup(sizeof(struct uma_bucket), sizeof(void *)); size += sizeof(void *) * ubz->ubz_entries; ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size, NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_MTXCLASS | UMA_ZFLAG_BUCKET | UMA_ZONE_NUMA); } } /* * Given a desired number of entries for a bucket, return the zone from which * to allocate the bucket. */ static struct uma_bucket_zone * bucket_zone_lookup(int entries) { struct uma_bucket_zone *ubz; for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) if (ubz->ubz_entries >= entries) return (ubz); ubz--; return (ubz); } +static struct uma_bucket_zone * +bucket_zone_max(uma_zone_t zone, int nitems) +{ + struct uma_bucket_zone *ubz; + int bpcpu; + + bpcpu = 2; +#ifdef UMA_XDOMAIN + if ((zone->uz_flags & UMA_ZONE_NUMA) != 0) + /* Count the cross-domain bucket. */ + bpcpu++; +#endif + + for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) + if (ubz->ubz_entries * bpcpu * mp_ncpus > nitems) + break; + if (ubz == &bucket_zones[0]) + ubz = NULL; + else + ubz--; + return (ubz); +} + static int bucket_select(int size) { struct uma_bucket_zone *ubz; ubz = &bucket_zones[0]; if (size > ubz->ubz_maxsize) return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1); for (; ubz->ubz_entries != 0; ubz++) if (ubz->ubz_maxsize < size) break; ubz--; return (ubz->ubz_entries); } static uma_bucket_t bucket_alloc(uma_zone_t zone, void *udata, int flags) { struct uma_bucket_zone *ubz; uma_bucket_t bucket; /* * This is to stop us from allocating per cpu buckets while we're * running out of vm.boot_pages. Otherwise, we would exhaust the * boot pages. This also prevents us from allocating buckets in * low memory situations. */ if (bucketdisable) return (NULL); /* * To limit bucket recursion we store the original zone flags * in a cookie passed via zalloc_arg/zfree_arg. This allows the * NOVM flag to persist even through deep recursions. We also * store ZFLAG_BUCKET once we have recursed attempting to allocate * a bucket for a bucket zone so we do not allow infinite bucket * recursion. This cookie will even persist to frees of unused * buckets via the allocation path or bucket allocations in the * free path. */ if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0) udata = (void *)(uintptr_t)zone->uz_flags; else { if ((uintptr_t)udata & UMA_ZFLAG_BUCKET) return (NULL); udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET); } if ((uintptr_t)udata & UMA_ZFLAG_CACHEONLY) flags |= M_NOVM; ubz = bucket_zone_lookup(zone->uz_count); if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0) ubz++; bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags); if (bucket) { #ifdef INVARIANTS bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries); #endif bucket->ub_cnt = 0; bucket->ub_entries = ubz->ubz_entries; } return (bucket); } static void bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata) { struct uma_bucket_zone *ubz; KASSERT(bucket->ub_cnt == 0, ("bucket_free: Freeing a non free bucket.")); if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0) udata = (void *)(uintptr_t)zone->uz_flags; ubz = bucket_zone_lookup(bucket->ub_entries); uma_zfree_arg(ubz->ubz_zone, bucket, udata); } static void bucket_zone_drain(void) { struct uma_bucket_zone *ubz; for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) uma_zone_reclaim(ubz->ubz_zone, UMA_RECLAIM_DRAIN); } /* * Attempt to satisfy an allocation by retrieving a full bucket from one of the * zone's caches. */ static uma_bucket_t zone_fetch_bucket(uma_zone_t zone, uma_zone_domain_t zdom) { uma_bucket_t bucket; ZONE_LOCK_ASSERT(zone); if ((bucket = TAILQ_FIRST(&zdom->uzd_buckets)) != NULL) { MPASS(zdom->uzd_nitems >= bucket->ub_cnt); TAILQ_REMOVE(&zdom->uzd_buckets, bucket, ub_link); zdom->uzd_nitems -= bucket->ub_cnt; if (zdom->uzd_imin > zdom->uzd_nitems) zdom->uzd_imin = zdom->uzd_nitems; zone->uz_bkt_count -= bucket->ub_cnt; } return (bucket); } /* * Insert a full bucket into the specified cache. The "ws" parameter indicates * whether the bucket's contents should be counted as part of the zone's working * set. */ static void zone_put_bucket(uma_zone_t zone, uma_zone_domain_t zdom, uma_bucket_t bucket, const bool ws) { ZONE_LOCK_ASSERT(zone); KASSERT(!ws || zone->uz_bkt_count < zone->uz_bkt_max, ("%s: zone %p overflow", __func__, zone)); if (ws) TAILQ_INSERT_HEAD(&zdom->uzd_buckets, bucket, ub_link); else TAILQ_INSERT_TAIL(&zdom->uzd_buckets, bucket, ub_link); zdom->uzd_nitems += bucket->ub_cnt; if (ws && zdom->uzd_imax < zdom->uzd_nitems) zdom->uzd_imax = zdom->uzd_nitems; zone->uz_bkt_count += bucket->ub_cnt; } static void zone_log_warning(uma_zone_t zone) { static const struct timeval warninterval = { 300, 0 }; if (!zone_warnings || zone->uz_warning == NULL) return; if (ratecheck(&zone->uz_ratecheck, &warninterval)) printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning); } static inline void zone_maxaction(uma_zone_t zone) { if (zone->uz_maxaction.ta_func != NULL) taskqueue_enqueue(taskqueue_thread, &zone->uz_maxaction); } /* * Routine called by timeout which is used to fire off some time interval * based calculations. (stats, hash size, etc.) * * Arguments: * arg Unused * * Returns: * Nothing */ static void uma_timeout(void *unused) { bucket_enable(); zone_foreach(zone_timeout); /* Reschedule this event */ callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL); } /* * Update the working set size estimate for the zone's bucket cache. * The constants chosen here are somewhat arbitrary. With an update period of * 20s (UMA_TIMEOUT), this estimate is dominated by zone activity over the * last 100s. */ static void zone_domain_update_wss(uma_zone_domain_t zdom) { long wss; MPASS(zdom->uzd_imax >= zdom->uzd_imin); wss = zdom->uzd_imax - zdom->uzd_imin; zdom->uzd_imax = zdom->uzd_imin = zdom->uzd_nitems; zdom->uzd_wss = (4 * wss + zdom->uzd_wss) / 5; } /* * Routine to perform timeout driven calculations. This expands the * hashes and does per cpu statistics aggregation. * * Returns nothing. */ static void zone_timeout(uma_zone_t zone) { uma_keg_t keg; u_int slabs; if ((zone->uz_flags & UMA_ZONE_HASH) == 0) goto update_wss; keg = zone->uz_keg; KEG_LOCK(keg); /* * Expand the keg hash table. * * This is done if the number of slabs is larger than the hash size. * What I'm trying to do here is completely reduce collisions. This * may be a little aggressive. Should I allow for two collisions max? */ if (keg->uk_flags & UMA_ZONE_HASH && (slabs = keg->uk_pages / keg->uk_ppera) > keg->uk_hash.uh_hashsize) { struct uma_hash newhash; struct uma_hash oldhash; int ret; /* * This is so involved because allocating and freeing * while the keg lock is held will lead to deadlock. * I have to do everything in stages and check for * races. */ KEG_UNLOCK(keg); ret = hash_alloc(&newhash, 1 << fls(slabs)); KEG_LOCK(keg); if (ret) { if (hash_expand(&keg->uk_hash, &newhash)) { oldhash = keg->uk_hash; keg->uk_hash = newhash; } else oldhash = newhash; KEG_UNLOCK(keg); hash_free(&oldhash); return; } } KEG_UNLOCK(keg); update_wss: ZONE_LOCK(zone); for (int i = 0; i < vm_ndomains; i++) zone_domain_update_wss(&zone->uz_domain[i]); ZONE_UNLOCK(zone); } /* * Allocate and zero fill the next sized hash table from the appropriate * backing store. * * Arguments: * hash A new hash structure with the old hash size in uh_hashsize * * Returns: * 1 on success and 0 on failure. */ static int hash_alloc(struct uma_hash *hash, u_int size) { size_t alloc; KASSERT(powerof2(size), ("hash size must be power of 2")); if (size > UMA_HASH_SIZE_INIT) { hash->uh_hashsize = size; alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize; hash->uh_slab_hash = (struct slabhead *)malloc(alloc, M_UMAHASH, M_NOWAIT); } else { alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT; hash->uh_slab_hash = zone_alloc_item(hashzone, NULL, UMA_ANYDOMAIN, M_WAITOK); hash->uh_hashsize = UMA_HASH_SIZE_INIT; } if (hash->uh_slab_hash) { bzero(hash->uh_slab_hash, alloc); hash->uh_hashmask = hash->uh_hashsize - 1; return (1); } return (0); } /* * Expands the hash table for HASH zones. This is done from zone_timeout * to reduce collisions. This must not be done in the regular allocation * path, otherwise, we can recurse on the vm while allocating pages. * * Arguments: * oldhash The hash you want to expand * newhash The hash structure for the new table * * Returns: * Nothing * * Discussion: */ static int hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash) { uma_slab_t slab; u_int hval; u_int idx; if (!newhash->uh_slab_hash) return (0); if (oldhash->uh_hashsize >= newhash->uh_hashsize) return (0); /* * I need to investigate hash algorithms for resizing without a * full rehash. */ for (idx = 0; idx < oldhash->uh_hashsize; idx++) while (!SLIST_EMPTY(&oldhash->uh_slab_hash[idx])) { slab = SLIST_FIRST(&oldhash->uh_slab_hash[idx]); SLIST_REMOVE_HEAD(&oldhash->uh_slab_hash[idx], us_hlink); hval = UMA_HASH(newhash, slab->us_data); SLIST_INSERT_HEAD(&newhash->uh_slab_hash[hval], slab, us_hlink); } return (1); } /* * Free the hash bucket to the appropriate backing store. * * Arguments: * slab_hash The hash bucket we're freeing * hashsize The number of entries in that hash bucket * * Returns: * Nothing */ static void hash_free(struct uma_hash *hash) { if (hash->uh_slab_hash == NULL) return; if (hash->uh_hashsize == UMA_HASH_SIZE_INIT) zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE); else free(hash->uh_slab_hash, M_UMAHASH); } /* * Frees all outstanding items in a bucket * * Arguments: * zone The zone to free to, must be unlocked. * bucket The free/alloc bucket with items, cpu queue must be locked. * * Returns: * Nothing */ static void bucket_drain(uma_zone_t zone, uma_bucket_t bucket) { int i; if (bucket == NULL) return; if (zone->uz_fini) for (i = 0; i < bucket->ub_cnt; i++) zone->uz_fini(bucket->ub_bucket[i], zone->uz_size); zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt); if (zone->uz_max_items > 0) { ZONE_LOCK(zone); zone->uz_items -= bucket->ub_cnt; if (zone->uz_sleepers && zone->uz_items < zone->uz_max_items) wakeup_one(zone); ZONE_UNLOCK(zone); } bucket->ub_cnt = 0; } /* * Drains the per cpu caches for a zone. * * NOTE: This may only be called while the zone is being turn down, and not * during normal operation. This is necessary in order that we do not have * to migrate CPUs to drain the per-CPU caches. * * Arguments: * zone The zone to drain, must be unlocked. * * Returns: * Nothing */ static void cache_drain(uma_zone_t zone) { uma_cache_t cache; int cpu; /* * XXX: It is safe to not lock the per-CPU caches, because we're * tearing down the zone anyway. I.e., there will be no further use * of the caches at this point. * * XXX: It would good to be able to assert that the zone is being * torn down to prevent improper use of cache_drain(). * * XXX: We lock the zone before passing into bucket_cache_reclaim() as * it is used elsewhere. Should the tear-down path be made special * there in some form? */ CPU_FOREACH(cpu) { cache = &zone->uz_cpu[cpu]; bucket_drain(zone, cache->uc_allocbucket); if (cache->uc_allocbucket != NULL) bucket_free(zone, cache->uc_allocbucket, NULL); cache->uc_allocbucket = NULL; bucket_drain(zone, cache->uc_freebucket); if (cache->uc_freebucket != NULL) bucket_free(zone, cache->uc_freebucket, NULL); cache->uc_freebucket = NULL; bucket_drain(zone, cache->uc_crossbucket); if (cache->uc_crossbucket != NULL) bucket_free(zone, cache->uc_crossbucket, NULL); cache->uc_crossbucket = NULL; } ZONE_LOCK(zone); bucket_cache_reclaim(zone, true); ZONE_UNLOCK(zone); } static void cache_shrink(uma_zone_t zone) { if (zone->uz_flags & UMA_ZFLAG_INTERNAL) return; ZONE_LOCK(zone); zone->uz_count = (zone->uz_count_min + zone->uz_count) / 2; ZONE_UNLOCK(zone); } static void cache_drain_safe_cpu(uma_zone_t zone) { uma_cache_t cache; uma_bucket_t b1, b2, b3; int domain; if (zone->uz_flags & UMA_ZFLAG_INTERNAL) return; b1 = b2 = b3 = NULL; ZONE_LOCK(zone); critical_enter(); if (zone->uz_flags & UMA_ZONE_NUMA) domain = PCPU_GET(domain); else domain = 0; cache = &zone->uz_cpu[curcpu]; if (cache->uc_allocbucket) { if (cache->uc_allocbucket->ub_cnt != 0) zone_put_bucket(zone, &zone->uz_domain[domain], cache->uc_allocbucket, false); else b1 = cache->uc_allocbucket; cache->uc_allocbucket = NULL; } if (cache->uc_freebucket) { if (cache->uc_freebucket->ub_cnt != 0) zone_put_bucket(zone, &zone->uz_domain[domain], cache->uc_freebucket, false); else b2 = cache->uc_freebucket; cache->uc_freebucket = NULL; } b3 = cache->uc_crossbucket; cache->uc_crossbucket = NULL; critical_exit(); ZONE_UNLOCK(zone); if (b1) bucket_free(zone, b1, NULL); if (b2) bucket_free(zone, b2, NULL); if (b3) { bucket_drain(zone, b3); bucket_free(zone, b3, NULL); } } /* * Safely drain per-CPU caches of a zone(s) to alloc bucket. * This is an expensive call because it needs to bind to all CPUs * one by one and enter a critical section on each of them in order * to safely access their cache buckets. * Zone lock must not be held on call this function. */ static void pcpu_cache_drain_safe(uma_zone_t zone) { int cpu; /* * Polite bucket sizes shrinking was not enouth, shrink aggressively. */ if (zone) cache_shrink(zone); else zone_foreach(cache_shrink); CPU_FOREACH(cpu) { thread_lock(curthread); sched_bind(curthread, cpu); thread_unlock(curthread); if (zone) cache_drain_safe_cpu(zone); else zone_foreach(cache_drain_safe_cpu); } thread_lock(curthread); sched_unbind(curthread); thread_unlock(curthread); } /* * Reclaim cached buckets from a zone. All buckets are reclaimed if the caller * requested a drain, otherwise the per-domain caches are trimmed to either * estimated working set size. */ static void bucket_cache_reclaim(uma_zone_t zone, bool drain) { uma_zone_domain_t zdom; uma_bucket_t bucket; long target, tofree; int i; for (i = 0; i < vm_ndomains; i++) { zdom = &zone->uz_domain[i]; /* * If we were asked to drain the zone, we are done only once * this bucket cache is empty. Otherwise, we reclaim items in * excess of the zone's estimated working set size. If the * difference nitems - imin is larger than the WSS estimate, * then the estimate will grow at the end of this interval and * we ignore the historical average. */ target = drain ? 0 : lmax(zdom->uzd_wss, zdom->uzd_nitems - zdom->uzd_imin); while (zdom->uzd_nitems > target) { bucket = TAILQ_LAST(&zdom->uzd_buckets, uma_bucketlist); if (bucket == NULL) break; tofree = bucket->ub_cnt; TAILQ_REMOVE(&zdom->uzd_buckets, bucket, ub_link); zdom->uzd_nitems -= tofree; /* * Shift the bounds of the current WSS interval to avoid * perturbing the estimate. */ zdom->uzd_imax -= lmin(zdom->uzd_imax, tofree); zdom->uzd_imin -= lmin(zdom->uzd_imin, tofree); ZONE_UNLOCK(zone); bucket_drain(zone, bucket); bucket_free(zone, bucket, NULL); ZONE_LOCK(zone); } } /* * Shrink the zone bucket size to ensure that the per-CPU caches * don't grow too large. */ if (zone->uz_count > zone->uz_count_min) zone->uz_count--; } static void keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start) { uint8_t *mem; int i; uint8_t flags; CTR4(KTR_UMA, "keg_free_slab keg %s(%p) slab %p, returning %d bytes", keg->uk_name, keg, slab, PAGE_SIZE * keg->uk_ppera); mem = slab->us_data; flags = slab->us_flags; i = start; if (keg->uk_fini != NULL) { for (i--; i > -1; i--) #ifdef INVARIANTS /* * trash_fini implies that dtor was trash_dtor. trash_fini * would check that memory hasn't been modified since free, * which executed trash_dtor. * That's why we need to run uma_dbg_kskip() check here, * albeit we don't make skip check for other init/fini * invocations. */ if (!uma_dbg_kskip(keg, slab->us_data + (keg->uk_rsize * i)) || keg->uk_fini != trash_fini) #endif keg->uk_fini(slab->us_data + (keg->uk_rsize * i), keg->uk_size); } if (keg->uk_flags & UMA_ZONE_OFFPAGE) zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE); keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera, flags); uma_total_dec(PAGE_SIZE * keg->uk_ppera); } /* * Frees pages from a keg back to the system. This is done on demand from * the pageout daemon. * * Returns nothing. */ static void keg_drain(uma_keg_t keg) { struct slabhead freeslabs = { 0 }; uma_domain_t dom; uma_slab_t slab, tmp; int i; /* * We don't want to take pages from statically allocated kegs at this * time */ if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL) return; CTR3(KTR_UMA, "keg_drain %s(%p) free items: %u", keg->uk_name, keg, keg->uk_free); KEG_LOCK(keg); if (keg->uk_free == 0) goto finished; for (i = 0; i < vm_ndomains; i++) { dom = &keg->uk_domain[i]; LIST_FOREACH_SAFE(slab, &dom->ud_free_slab, us_link, tmp) { /* We have nowhere to free these to. */ if (slab->us_flags & UMA_SLAB_BOOT) continue; LIST_REMOVE(slab, us_link); keg->uk_pages -= keg->uk_ppera; keg->uk_free -= keg->uk_ipers; if (keg->uk_flags & UMA_ZONE_HASH) UMA_HASH_REMOVE(&keg->uk_hash, slab, slab->us_data); SLIST_INSERT_HEAD(&freeslabs, slab, us_hlink); } } finished: KEG_UNLOCK(keg); while ((slab = SLIST_FIRST(&freeslabs)) != NULL) { SLIST_REMOVE(&freeslabs, slab, uma_slab, us_hlink); keg_free_slab(keg, slab, keg->uk_ipers); } } static void zone_reclaim(uma_zone_t zone, int waitok, bool drain) { /* * Set draining to interlock with zone_dtor() so we can release our * locks as we go. Only dtor() should do a WAITOK call since it * is the only call that knows the structure will still be available * when it wakes up. */ ZONE_LOCK(zone); while (zone->uz_flags & UMA_ZFLAG_RECLAIMING) { if (waitok == M_NOWAIT) goto out; msleep(zone, zone->uz_lockptr, PVM, "zonedrain", 1); } zone->uz_flags |= UMA_ZFLAG_RECLAIMING; bucket_cache_reclaim(zone, drain); ZONE_UNLOCK(zone); /* * The DRAINING flag protects us from being freed while * we're running. Normally the uma_rwlock would protect us but we * must be able to release and acquire the right lock for each keg. */ if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0) keg_drain(zone->uz_keg); ZONE_LOCK(zone); zone->uz_flags &= ~UMA_ZFLAG_RECLAIMING; wakeup(zone); out: ZONE_UNLOCK(zone); } static void zone_drain(uma_zone_t zone) { zone_reclaim(zone, M_NOWAIT, true); } static void zone_trim(uma_zone_t zone) { zone_reclaim(zone, M_NOWAIT, false); } /* * Allocate a new slab for a keg. This does not insert the slab onto a list. * If the allocation was successful, the keg lock will be held upon return, * otherwise the keg will be left unlocked. * * Arguments: * flags Wait flags for the item initialization routine * aflags Wait flags for the slab allocation * * Returns: * The slab that was allocated or NULL if there is no memory and the * caller specified M_NOWAIT. */ static uma_slab_t keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int domain, int flags, int aflags) { uma_alloc allocf; uma_slab_t slab; unsigned long size; uint8_t *mem; uint8_t sflags; int i; KASSERT(domain >= 0 && domain < vm_ndomains, ("keg_alloc_slab: domain %d out of range", domain)); KEG_LOCK_ASSERT(keg); MPASS(zone->uz_lockptr == &keg->uk_lock); allocf = keg->uk_allocf; KEG_UNLOCK(keg); slab = NULL; mem = NULL; if (keg->uk_flags & UMA_ZONE_OFFPAGE) { slab = zone_alloc_item(keg->uk_slabzone, NULL, domain, aflags); if (slab == NULL) goto out; } /* * This reproduces the old vm_zone behavior of zero filling pages the * first time they are added to a zone. * * Malloced items are zeroed in uma_zalloc. */ if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0) aflags |= M_ZERO; else aflags &= ~M_ZERO; if (keg->uk_flags & UMA_ZONE_NODUMP) aflags |= M_NODUMP; /* zone is passed for legacy reasons. */ size = keg->uk_ppera * PAGE_SIZE; mem = allocf(zone, size, domain, &sflags, aflags); if (mem == NULL) { if (keg->uk_flags & UMA_ZONE_OFFPAGE) zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE); slab = NULL; goto out; } uma_total_inc(size); /* Point the slab into the allocated memory */ if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) slab = (uma_slab_t )(mem + keg->uk_pgoff); if (keg->uk_flags & UMA_ZONE_VTOSLAB) for (i = 0; i < keg->uk_ppera; i++) vsetslab((vm_offset_t)mem + (i * PAGE_SIZE), slab); slab->us_keg = keg; slab->us_data = mem; slab->us_freecount = keg->uk_ipers; slab->us_flags = sflags; slab->us_domain = domain; BIT_FILL(SLAB_SETSIZE, &slab->us_free); #ifdef INVARIANTS BIT_ZERO(SLAB_SETSIZE, &slab->us_debugfree); #endif if (keg->uk_init != NULL) { for (i = 0; i < keg->uk_ipers; i++) if (keg->uk_init(slab->us_data + (keg->uk_rsize * i), keg->uk_size, flags) != 0) break; if (i != keg->uk_ipers) { keg_free_slab(keg, slab, i); slab = NULL; goto out; } } KEG_LOCK(keg); CTR3(KTR_UMA, "keg_alloc_slab: allocated slab %p for %s(%p)", slab, keg->uk_name, keg); if (keg->uk_flags & UMA_ZONE_HASH) UMA_HASH_INSERT(&keg->uk_hash, slab, mem); keg->uk_pages += keg->uk_ppera; keg->uk_free += keg->uk_ipers; out: return (slab); } /* * This function is intended to be used early on in place of page_alloc() so * that we may use the boot time page cache to satisfy allocations before * the VM is ready. */ static void * startup_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag, int wait) { uma_keg_t keg; void *mem; int pages; keg = zone->uz_keg; /* * If we are in BOOT_BUCKETS or higher, than switch to real * allocator. Zones with page sized slabs switch at BOOT_PAGEALLOC. */ switch (booted) { case BOOT_COLD: case BOOT_STRAPPED: break; case BOOT_PAGEALLOC: if (keg->uk_ppera > 1) break; case BOOT_BUCKETS: case BOOT_RUNNING: #ifdef UMA_MD_SMALL_ALLOC keg->uk_allocf = (keg->uk_ppera > 1) ? page_alloc : uma_small_alloc; #else keg->uk_allocf = page_alloc; #endif return keg->uk_allocf(zone, bytes, domain, pflag, wait); } /* * Check our small startup cache to see if it has pages remaining. */ pages = howmany(bytes, PAGE_SIZE); KASSERT(pages > 0, ("%s can't reserve 0 pages", __func__)); if (pages > boot_pages) panic("UMA zone \"%s\": Increase vm.boot_pages", zone->uz_name); #ifdef DIAGNOSTIC printf("%s from \"%s\", %d boot pages left\n", __func__, zone->uz_name, boot_pages); #endif mem = bootmem; boot_pages -= pages; bootmem += pages * PAGE_SIZE; *pflag = UMA_SLAB_BOOT; return (mem); } /* * Allocates a number of pages from the system * * Arguments: * bytes The number of bytes requested * wait Shall we wait? * * Returns: * A pointer to the alloced memory or possibly * NULL if M_NOWAIT is set. */ static void * page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag, int wait) { void *p; /* Returned page */ *pflag = UMA_SLAB_KERNEL; p = (void *)kmem_malloc_domainset(DOMAINSET_FIXED(domain), bytes, wait); return (p); } static void * pcpu_page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag, int wait) { struct pglist alloctail; vm_offset_t addr, zkva; int cpu, flags; vm_page_t p, p_next; #ifdef NUMA struct pcpu *pc; #endif MPASS(bytes == (mp_maxid + 1) * PAGE_SIZE); TAILQ_INIT(&alloctail); flags = VM_ALLOC_SYSTEM | VM_ALLOC_WIRED | VM_ALLOC_NOOBJ | malloc2vm_flags(wait); *pflag = UMA_SLAB_KERNEL; for (cpu = 0; cpu <= mp_maxid; cpu++) { if (CPU_ABSENT(cpu)) { p = vm_page_alloc(NULL, 0, flags); } else { #ifndef NUMA p = vm_page_alloc(NULL, 0, flags); #else pc = pcpu_find(cpu); p = vm_page_alloc_domain(NULL, 0, pc->pc_domain, flags); if (__predict_false(p == NULL)) p = vm_page_alloc(NULL, 0, flags); #endif } if (__predict_false(p == NULL)) goto fail; TAILQ_INSERT_TAIL(&alloctail, p, listq); } if ((addr = kva_alloc(bytes)) == 0) goto fail; zkva = addr; TAILQ_FOREACH(p, &alloctail, listq) { pmap_qenter(zkva, &p, 1); zkva += PAGE_SIZE; } return ((void*)addr); fail: TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) { vm_page_unwire_noq(p); vm_page_free(p); } return (NULL); } /* * Allocates a number of pages from within an object * * Arguments: * bytes The number of bytes requested * wait Shall we wait? * * Returns: * A pointer to the alloced memory or possibly * NULL if M_NOWAIT is set. */ static void * noobj_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags, int wait) { TAILQ_HEAD(, vm_page) alloctail; u_long npages; vm_offset_t retkva, zkva; vm_page_t p, p_next; uma_keg_t keg; TAILQ_INIT(&alloctail); keg = zone->uz_keg; npages = howmany(bytes, PAGE_SIZE); while (npages > 0) { p = vm_page_alloc_domain(NULL, 0, domain, VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED | VM_ALLOC_NOOBJ | ((wait & M_WAITOK) != 0 ? VM_ALLOC_WAITOK : VM_ALLOC_NOWAIT)); if (p != NULL) { /* * Since the page does not belong to an object, its * listq is unused. */ TAILQ_INSERT_TAIL(&alloctail, p, listq); npages--; continue; } /* * Page allocation failed, free intermediate pages and * exit. */ TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) { vm_page_unwire_noq(p); vm_page_free(p); } return (NULL); } *flags = UMA_SLAB_PRIV; zkva = keg->uk_kva + atomic_fetchadd_long(&keg->uk_offset, round_page(bytes)); retkva = zkva; TAILQ_FOREACH(p, &alloctail, listq) { pmap_qenter(zkva, &p, 1); zkva += PAGE_SIZE; } return ((void *)retkva); } /* * Frees a number of pages to the system * * Arguments: * mem A pointer to the memory to be freed * size The size of the memory being freed * flags The original p->us_flags field * * Returns: * Nothing */ static void page_free(void *mem, vm_size_t size, uint8_t flags) { if ((flags & UMA_SLAB_KERNEL) == 0) panic("UMA: page_free used with invalid flags %x", flags); kmem_free((vm_offset_t)mem, size); } /* * Frees pcpu zone allocations * * Arguments: * mem A pointer to the memory to be freed * size The size of the memory being freed * flags The original p->us_flags field * * Returns: * Nothing */ static void pcpu_page_free(void *mem, vm_size_t size, uint8_t flags) { vm_offset_t sva, curva; vm_paddr_t paddr; vm_page_t m; MPASS(size == (mp_maxid+1)*PAGE_SIZE); sva = (vm_offset_t)mem; for (curva = sva; curva < sva + size; curva += PAGE_SIZE) { paddr = pmap_kextract(curva); m = PHYS_TO_VM_PAGE(paddr); vm_page_unwire_noq(m); vm_page_free(m); } pmap_qremove(sva, size >> PAGE_SHIFT); kva_free(sva, size); } /* * Zero fill initializer * * Arguments/Returns follow uma_init specifications */ static int zero_init(void *mem, int size, int flags) { bzero(mem, size); return (0); } /* * Finish creating a small uma keg. This calculates ipers, and the keg size. * * Arguments * keg The zone we should initialize * * Returns * Nothing */ static void keg_small_init(uma_keg_t keg) { u_int rsize; u_int memused; u_int wastedspace; u_int shsize; u_int slabsize; if (keg->uk_flags & UMA_ZONE_PCPU) { u_int ncpus = (mp_maxid + 1) ? (mp_maxid + 1) : MAXCPU; slabsize = UMA_PCPU_ALLOC_SIZE; keg->uk_ppera = ncpus; } else { slabsize = UMA_SLAB_SIZE; keg->uk_ppera = 1; } /* * Calculate the size of each allocation (rsize) according to * alignment. If the requested size is smaller than we have * allocation bits for we round it up. */ rsize = keg->uk_size; if (rsize < slabsize / SLAB_SETSIZE) rsize = slabsize / SLAB_SETSIZE; if (rsize & keg->uk_align) rsize = (rsize & ~keg->uk_align) + (keg->uk_align + 1); keg->uk_rsize = rsize; KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 || keg->uk_rsize < UMA_PCPU_ALLOC_SIZE, ("%s: size %u too large", __func__, keg->uk_rsize)); if (keg->uk_flags & UMA_ZONE_OFFPAGE) shsize = 0; else shsize = SIZEOF_UMA_SLAB; if (rsize <= slabsize - shsize) keg->uk_ipers = (slabsize - shsize) / rsize; else { /* Handle special case when we have 1 item per slab, so * alignment requirement can be relaxed. */ KASSERT(keg->uk_size <= slabsize - shsize, ("%s: size %u greater than slab", __func__, keg->uk_size)); keg->uk_ipers = 1; } KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE, ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers)); memused = keg->uk_ipers * rsize + shsize; wastedspace = slabsize - memused; /* * We can't do OFFPAGE if we're internal or if we've been * asked to not go to the VM for buckets. If we do this we * may end up going to the VM for slabs which we do not * want to do if we're UMA_ZFLAG_CACHEONLY as a result * of UMA_ZONE_VM, which clearly forbids it. */ if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) || (keg->uk_flags & UMA_ZFLAG_CACHEONLY)) return; /* * See if using an OFFPAGE slab will limit our waste. Only do * this if it permits more items per-slab. * * XXX We could try growing slabsize to limit max waste as well. * Historically this was not done because the VM could not * efficiently handle contiguous allocations. */ if ((wastedspace >= slabsize / UMA_MAX_WASTE) && (keg->uk_ipers < (slabsize / keg->uk_rsize))) { keg->uk_ipers = slabsize / keg->uk_rsize; KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE, ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers)); CTR6(KTR_UMA, "UMA decided we need offpage slab headers for " "keg: %s(%p), calculated wastedspace = %d, " "maximum wasted space allowed = %d, " "calculated ipers = %d, " "new wasted space = %d\n", keg->uk_name, keg, wastedspace, slabsize / UMA_MAX_WASTE, keg->uk_ipers, slabsize - keg->uk_ipers * keg->uk_rsize); /* * If we had access to memory to embed a slab header we * also have a page structure to use vtoslab() instead of * hash to find slabs. If the zone was explicitly created * OFFPAGE we can't necessarily touch the memory. */ if ((keg->uk_flags & UMA_ZONE_OFFPAGE) == 0) keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB; } if ((keg->uk_flags & UMA_ZONE_OFFPAGE) && (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0) keg->uk_flags |= UMA_ZONE_HASH; } /* * Finish creating a large (> UMA_SLAB_SIZE) uma kegs. Just give in and do * OFFPAGE for now. When I can allow for more dynamic slab sizes this will be * more complicated. * * Arguments * keg The keg we should initialize * * Returns * Nothing */ static void keg_large_init(uma_keg_t keg) { KASSERT(keg != NULL, ("Keg is null in keg_large_init")); KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0, ("%s: Cannot large-init a UMA_ZONE_PCPU keg", __func__)); keg->uk_ppera = howmany(keg->uk_size, PAGE_SIZE); keg->uk_ipers = 1; keg->uk_rsize = keg->uk_size; /* Check whether we have enough space to not do OFFPAGE. */ if ((keg->uk_flags & UMA_ZONE_OFFPAGE) == 0 && PAGE_SIZE * keg->uk_ppera - keg->uk_rsize < SIZEOF_UMA_SLAB) { /* * We can't do OFFPAGE if we're internal, in which case * we need an extra page per allocation to contain the * slab header. */ if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) == 0) keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB; else keg->uk_ppera++; } if ((keg->uk_flags & UMA_ZONE_OFFPAGE) && (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0) keg->uk_flags |= UMA_ZONE_HASH; } static void keg_cachespread_init(uma_keg_t keg) { int alignsize; int trailer; int pages; int rsize; KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0, ("%s: Cannot cachespread-init a UMA_ZONE_PCPU keg", __func__)); alignsize = keg->uk_align + 1; rsize = keg->uk_size; /* * We want one item to start on every align boundary in a page. To * do this we will span pages. We will also extend the item by the * size of align if it is an even multiple of align. Otherwise, it * would fall on the same boundary every time. */ if (rsize & keg->uk_align) rsize = (rsize & ~keg->uk_align) + alignsize; if ((rsize & alignsize) == 0) rsize += alignsize; trailer = rsize - keg->uk_size; pages = (rsize * (PAGE_SIZE / alignsize)) / PAGE_SIZE; pages = MIN(pages, (128 * 1024) / PAGE_SIZE); keg->uk_rsize = rsize; keg->uk_ppera = pages; keg->uk_ipers = ((pages * PAGE_SIZE) + trailer) / rsize; keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB; KASSERT(keg->uk_ipers <= SLAB_SETSIZE, ("%s: keg->uk_ipers too high(%d) increase max_ipers", __func__, keg->uk_ipers)); } /* * Keg header ctor. This initializes all fields, locks, etc. And inserts * the keg onto the global keg list. * * Arguments/Returns follow uma_ctor specifications * udata Actually uma_kctor_args */ static int keg_ctor(void *mem, int size, void *udata, int flags) { struct uma_kctor_args *arg = udata; uma_keg_t keg = mem; uma_zone_t zone; bzero(keg, size); keg->uk_size = arg->size; keg->uk_init = arg->uminit; keg->uk_fini = arg->fini; keg->uk_align = arg->align; keg->uk_free = 0; keg->uk_reserve = 0; keg->uk_pages = 0; keg->uk_flags = arg->flags; keg->uk_slabzone = NULL; /* * We use a global round-robin policy by default. Zones with * UMA_ZONE_NUMA set will use first-touch instead, in which case the * iterator is never run. */ keg->uk_dr.dr_policy = DOMAINSET_RR(); keg->uk_dr.dr_iter = 0; /* * The master zone is passed to us at keg-creation time. */ zone = arg->zone; keg->uk_name = zone->uz_name; if (arg->flags & UMA_ZONE_VM) keg->uk_flags |= UMA_ZFLAG_CACHEONLY; if (arg->flags & UMA_ZONE_ZINIT) keg->uk_init = zero_init; if (arg->flags & UMA_ZONE_MALLOC) keg->uk_flags |= UMA_ZONE_VTOSLAB; if (arg->flags & UMA_ZONE_PCPU) #ifdef SMP keg->uk_flags |= UMA_ZONE_OFFPAGE; #else keg->uk_flags &= ~UMA_ZONE_PCPU; #endif if (keg->uk_flags & UMA_ZONE_CACHESPREAD) { keg_cachespread_init(keg); } else { if (keg->uk_size > UMA_SLAB_SPACE) keg_large_init(keg); else keg_small_init(keg); } if (keg->uk_flags & UMA_ZONE_OFFPAGE) keg->uk_slabzone = slabzone; /* * If we haven't booted yet we need allocations to go through the * startup cache until the vm is ready. */ if (booted < BOOT_PAGEALLOC) keg->uk_allocf = startup_alloc; #ifdef UMA_MD_SMALL_ALLOC else if (keg->uk_ppera == 1) keg->uk_allocf = uma_small_alloc; #endif else if (keg->uk_flags & UMA_ZONE_PCPU) keg->uk_allocf = pcpu_page_alloc; else keg->uk_allocf = page_alloc; #ifdef UMA_MD_SMALL_ALLOC if (keg->uk_ppera == 1) keg->uk_freef = uma_small_free; else #endif if (keg->uk_flags & UMA_ZONE_PCPU) keg->uk_freef = pcpu_page_free; else keg->uk_freef = page_free; /* * Initialize keg's lock */ KEG_LOCK_INIT(keg, (arg->flags & UMA_ZONE_MTXCLASS)); /* * If we're putting the slab header in the actual page we need to * figure out where in each page it goes. See SIZEOF_UMA_SLAB * macro definition. */ if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) { keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - SIZEOF_UMA_SLAB; /* * The only way the following is possible is if with our * UMA_ALIGN_PTR adjustments we are now bigger than * UMA_SLAB_SIZE. I haven't checked whether this is * mathematically possible for all cases, so we make * sure here anyway. */ KASSERT(keg->uk_pgoff + sizeof(struct uma_slab) <= PAGE_SIZE * keg->uk_ppera, ("zone %s ipers %d rsize %d size %d slab won't fit", zone->uz_name, keg->uk_ipers, keg->uk_rsize, keg->uk_size)); } if (keg->uk_flags & UMA_ZONE_HASH) hash_alloc(&keg->uk_hash, 0); CTR5(KTR_UMA, "keg_ctor %p zone %s(%p) out %d free %d\n", keg, zone->uz_name, zone, (keg->uk_pages / keg->uk_ppera) * keg->uk_ipers - keg->uk_free, keg->uk_free); LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link); rw_wlock(&uma_rwlock); LIST_INSERT_HEAD(&uma_kegs, keg, uk_link); rw_wunlock(&uma_rwlock); return (0); } static void zone_alloc_counters(uma_zone_t zone) { zone->uz_allocs = counter_u64_alloc(M_WAITOK); zone->uz_frees = counter_u64_alloc(M_WAITOK); zone->uz_fails = counter_u64_alloc(M_WAITOK); } /* * Zone header ctor. This initializes all fields, locks, etc. * * Arguments/Returns follow uma_ctor specifications * udata Actually uma_zctor_args */ static int zone_ctor(void *mem, int size, void *udata, int flags) { struct uma_zctor_args *arg = udata; uma_zone_t zone = mem; uma_zone_t z; uma_keg_t keg; int i; bzero(zone, size); zone->uz_name = arg->name; zone->uz_ctor = arg->ctor; zone->uz_dtor = arg->dtor; zone->uz_init = NULL; zone->uz_fini = NULL; zone->uz_sleeps = 0; zone->uz_xdomain = 0; zone->uz_count = 0; zone->uz_count_min = 0; zone->uz_count_max = BUCKET_MAX; zone->uz_flags = 0; zone->uz_warning = NULL; /* The domain structures follow the cpu structures. */ zone->uz_domain = (struct uma_zone_domain *)&zone->uz_cpu[mp_ncpus]; zone->uz_bkt_max = ULONG_MAX; timevalclear(&zone->uz_ratecheck); if (__predict_true(booted == BOOT_RUNNING)) zone_alloc_counters(zone); else { zone->uz_allocs = EARLY_COUNTER; zone->uz_frees = EARLY_COUNTER; zone->uz_fails = EARLY_COUNTER; } for (i = 0; i < vm_ndomains; i++) TAILQ_INIT(&zone->uz_domain[i].uzd_buckets); /* * This is a pure cache zone, no kegs. */ if (arg->import) { if (arg->flags & UMA_ZONE_VM) arg->flags |= UMA_ZFLAG_CACHEONLY; zone->uz_flags = arg->flags; zone->uz_size = arg->size; zone->uz_import = arg->import; zone->uz_release = arg->release; zone->uz_arg = arg->arg; zone->uz_lockptr = &zone->uz_lock; ZONE_LOCK_INIT(zone, (arg->flags & UMA_ZONE_MTXCLASS)); rw_wlock(&uma_rwlock); LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link); rw_wunlock(&uma_rwlock); goto out; } /* * Use the regular zone/keg/slab allocator. */ zone->uz_import = (uma_import)zone_import; zone->uz_release = (uma_release)zone_release; zone->uz_arg = zone; keg = arg->keg; if (arg->flags & UMA_ZONE_SECONDARY) { KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg")); zone->uz_init = arg->uminit; zone->uz_fini = arg->fini; zone->uz_lockptr = &keg->uk_lock; zone->uz_flags |= UMA_ZONE_SECONDARY; rw_wlock(&uma_rwlock); ZONE_LOCK(zone); LIST_FOREACH(z, &keg->uk_zones, uz_link) { if (LIST_NEXT(z, uz_link) == NULL) { LIST_INSERT_AFTER(z, zone, uz_link); break; } } ZONE_UNLOCK(zone); rw_wunlock(&uma_rwlock); } else if (keg == NULL) { if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini, arg->align, arg->flags)) == NULL) return (ENOMEM); } else { struct uma_kctor_args karg; int error; /* We should only be here from uma_startup() */ karg.size = arg->size; karg.uminit = arg->uminit; karg.fini = arg->fini; karg.align = arg->align; karg.flags = arg->flags; karg.zone = zone; error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg, flags); if (error) return (error); } zone->uz_keg = keg; zone->uz_size = keg->uk_size; zone->uz_flags |= (keg->uk_flags & (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT)); /* * Some internal zones don't have room allocated for the per cpu * caches. If we're internal, bail out here. */ if (keg->uk_flags & UMA_ZFLAG_INTERNAL) { KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0, ("Secondary zone requested UMA_ZFLAG_INTERNAL")); return (0); } out: KASSERT((arg->flags & (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET)) != (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET), ("Invalid zone flag combination")); if ((arg->flags & UMA_ZONE_MAXBUCKET) != 0) { zone->uz_count = BUCKET_MAX; } else if ((arg->flags & UMA_ZONE_MINBUCKET) != 0) { zone->uz_count = BUCKET_MIN; zone->uz_count_max = BUCKET_MIN; } else if ((arg->flags & UMA_ZONE_NOBUCKET) != 0) zone->uz_count = 0; else zone->uz_count = bucket_select(zone->uz_size); zone->uz_count_min = zone->uz_count; return (0); } /* * Keg header dtor. This frees all data, destroys locks, frees the hash * table and removes the keg from the global list. * * Arguments/Returns follow uma_dtor specifications * udata unused */ static void keg_dtor(void *arg, int size, void *udata) { uma_keg_t keg; keg = (uma_keg_t)arg; KEG_LOCK(keg); if (keg->uk_free != 0) { printf("Freed UMA keg (%s) was not empty (%d items). " " Lost %d pages of memory.\n", keg->uk_name ? keg->uk_name : "", keg->uk_free, keg->uk_pages); } KEG_UNLOCK(keg); hash_free(&keg->uk_hash); KEG_LOCK_FINI(keg); } /* * Zone header dtor. * * Arguments/Returns follow uma_dtor specifications * udata unused */ static void zone_dtor(void *arg, int size, void *udata) { uma_zone_t zone; uma_keg_t keg; zone = (uma_zone_t)arg; if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL)) cache_drain(zone); rw_wlock(&uma_rwlock); LIST_REMOVE(zone, uz_link); rw_wunlock(&uma_rwlock); /* * XXX there are some races here where * the zone can be drained but zone lock * released and then refilled before we * remove it... we dont care for now */ zone_reclaim(zone, M_WAITOK, true); /* * We only destroy kegs from non secondary/non cache zones. */ if ((zone->uz_flags & (UMA_ZONE_SECONDARY | UMA_ZFLAG_CACHE)) == 0) { keg = zone->uz_keg; rw_wlock(&uma_rwlock); LIST_REMOVE(keg, uk_link); rw_wunlock(&uma_rwlock); zone_free_item(kegs, keg, NULL, SKIP_NONE); } counter_u64_free(zone->uz_allocs); counter_u64_free(zone->uz_frees); counter_u64_free(zone->uz_fails); if (zone->uz_lockptr == &zone->uz_lock) ZONE_LOCK_FINI(zone); } /* * Traverses every zone in the system and calls a callback * * Arguments: * zfunc A pointer to a function which accepts a zone * as an argument. * * Returns: * Nothing */ static void zone_foreach(void (*zfunc)(uma_zone_t)) { uma_keg_t keg; uma_zone_t zone; /* * Before BOOT_RUNNING we are guaranteed to be single * threaded, so locking isn't needed. Startup functions * are allowed to use M_WAITOK. */ if (__predict_true(booted == BOOT_RUNNING)) rw_rlock(&uma_rwlock); LIST_FOREACH(keg, &uma_kegs, uk_link) { LIST_FOREACH(zone, &keg->uk_zones, uz_link) zfunc(zone); } LIST_FOREACH(zone, &uma_cachezones, uz_link) zfunc(zone); if (__predict_true(booted == BOOT_RUNNING)) rw_runlock(&uma_rwlock); } /* * Count how many pages do we need to bootstrap. VM supplies * its need in early zones in the argument, we add up our zones, * which consist of: UMA Slabs, UMA Hash and 9 Bucket zones. The * zone of zones and zone of kegs are accounted separately. */ #define UMA_BOOT_ZONES 11 /* Zone of zones and zone of kegs have arbitrary alignment. */ #define UMA_BOOT_ALIGN 32 static int zsize, ksize; int uma_startup_count(int vm_zones) { int zones, pages; ksize = sizeof(struct uma_keg) + (sizeof(struct uma_domain) * vm_ndomains); zsize = sizeof(struct uma_zone) + (sizeof(struct uma_cache) * (mp_maxid + 1)) + (sizeof(struct uma_zone_domain) * vm_ndomains); /* * Memory for the zone of kegs and its keg, * and for zone of zones. */ pages = howmany(roundup(zsize, CACHE_LINE_SIZE) * 2 + roundup(ksize, CACHE_LINE_SIZE), PAGE_SIZE); #ifdef UMA_MD_SMALL_ALLOC zones = UMA_BOOT_ZONES; #else zones = UMA_BOOT_ZONES + vm_zones; vm_zones = 0; #endif /* Memory for the rest of startup zones, UMA and VM, ... */ if (zsize > UMA_SLAB_SPACE) { /* See keg_large_init(). */ u_int ppera; ppera = howmany(roundup2(zsize, UMA_BOOT_ALIGN), PAGE_SIZE); if (PAGE_SIZE * ppera - roundup2(zsize, UMA_BOOT_ALIGN) < SIZEOF_UMA_SLAB) ppera++; pages += (zones + vm_zones) * ppera; } else if (roundup2(zsize, UMA_BOOT_ALIGN) > UMA_SLAB_SPACE) /* See keg_small_init() special case for uk_ppera = 1. */ pages += zones; else pages += howmany(zones, UMA_SLAB_SPACE / roundup2(zsize, UMA_BOOT_ALIGN)); /* ... and their kegs. Note that zone of zones allocates a keg! */ pages += howmany(zones + 1, UMA_SLAB_SPACE / roundup2(ksize, UMA_BOOT_ALIGN)); /* * Most of startup zones are not going to be offpages, that's * why we use UMA_SLAB_SPACE instead of UMA_SLAB_SIZE in all * calculations. Some large bucket zones will be offpage, and * thus will allocate hashes. We take conservative approach * and assume that all zones may allocate hash. This may give * us some positive inaccuracy, usually an extra single page. */ pages += howmany(zones, UMA_SLAB_SPACE / (sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT)); return (pages); } void uma_startup(void *mem, int npages) { struct uma_zctor_args args; uma_keg_t masterkeg; uintptr_t m; #ifdef DIAGNOSTIC printf("Entering %s with %d boot pages configured\n", __func__, npages); #endif rw_init(&uma_rwlock, "UMA lock"); /* Use bootpages memory for the zone of zones and zone of kegs. */ m = (uintptr_t)mem; zones = (uma_zone_t)m; m += roundup(zsize, CACHE_LINE_SIZE); kegs = (uma_zone_t)m; m += roundup(zsize, CACHE_LINE_SIZE); masterkeg = (uma_keg_t)m; m += roundup(ksize, CACHE_LINE_SIZE); m = roundup(m, PAGE_SIZE); npages -= (m - (uintptr_t)mem) / PAGE_SIZE; mem = (void *)m; /* "manually" create the initial zone */ memset(&args, 0, sizeof(args)); args.name = "UMA Kegs"; args.size = ksize; args.ctor = keg_ctor; args.dtor = keg_dtor; args.uminit = zero_init; args.fini = NULL; args.keg = masterkeg; args.align = UMA_BOOT_ALIGN - 1; args.flags = UMA_ZFLAG_INTERNAL; zone_ctor(kegs, zsize, &args, M_WAITOK); bootmem = mem; boot_pages = npages; args.name = "UMA Zones"; args.size = zsize; args.ctor = zone_ctor; args.dtor = zone_dtor; args.uminit = zero_init; args.fini = NULL; args.keg = NULL; args.align = UMA_BOOT_ALIGN - 1; args.flags = UMA_ZFLAG_INTERNAL; zone_ctor(zones, zsize, &args, M_WAITOK); /* Now make a zone for slab headers */ slabzone = uma_zcreate("UMA Slabs", sizeof(struct uma_slab), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL); hashzone = uma_zcreate("UMA Hash", sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT, NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL); bucket_init(); booted = BOOT_STRAPPED; } void uma_startup1(void) { #ifdef DIAGNOSTIC printf("Entering %s with %d boot pages left\n", __func__, boot_pages); #endif booted = BOOT_PAGEALLOC; } void uma_startup2(void) { #ifdef DIAGNOSTIC printf("Entering %s with %d boot pages left\n", __func__, boot_pages); #endif booted = BOOT_BUCKETS; sx_init(&uma_reclaim_lock, "umareclaim"); bucket_enable(); } /* * Initialize our callout handle * */ static void uma_startup3(void) { #ifdef INVARIANTS TUNABLE_INT_FETCH("vm.debug.divisor", &dbg_divisor); uma_dbg_cnt = counter_u64_alloc(M_WAITOK); uma_skip_cnt = counter_u64_alloc(M_WAITOK); #endif zone_foreach(zone_alloc_counters); callout_init(&uma_callout, 1); callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL); booted = BOOT_RUNNING; } static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini, int align, uint32_t flags) { struct uma_kctor_args args; args.size = size; args.uminit = uminit; args.fini = fini; args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align; args.flags = flags; args.zone = zone; return (zone_alloc_item(kegs, &args, UMA_ANYDOMAIN, M_WAITOK)); } /* Public functions */ /* See uma.h */ void uma_set_align(int align) { if (align != UMA_ALIGN_CACHE) uma_align_cache = align; } /* See uma.h */ uma_zone_t uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor, uma_init uminit, uma_fini fini, int align, uint32_t flags) { struct uma_zctor_args args; uma_zone_t res; bool locked; KASSERT(powerof2(align + 1), ("invalid zone alignment %d for \"%s\"", align, name)); /* Sets all zones to a first-touch domain policy. */ #ifdef UMA_FIRSTTOUCH flags |= UMA_ZONE_NUMA; #endif /* This stuff is essential for the zone ctor */ memset(&args, 0, sizeof(args)); args.name = name; args.size = size; args.ctor = ctor; args.dtor = dtor; args.uminit = uminit; args.fini = fini; #ifdef INVARIANTS /* * If a zone is being created with an empty constructor and * destructor, pass UMA constructor/destructor which checks for * memory use after free. */ if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOFREE))) && ctor == NULL && dtor == NULL && uminit == NULL && fini == NULL) { args.ctor = trash_ctor; args.dtor = trash_dtor; args.uminit = trash_init; args.fini = trash_fini; } #endif args.align = align; args.flags = flags; args.keg = NULL; if (booted < BOOT_BUCKETS) { locked = false; } else { sx_slock(&uma_reclaim_lock); locked = true; } res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK); if (locked) sx_sunlock(&uma_reclaim_lock); return (res); } /* See uma.h */ uma_zone_t uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor, uma_init zinit, uma_fini zfini, uma_zone_t master) { struct uma_zctor_args args; uma_keg_t keg; uma_zone_t res; bool locked; keg = master->uz_keg; memset(&args, 0, sizeof(args)); args.name = name; args.size = keg->uk_size; args.ctor = ctor; args.dtor = dtor; args.uminit = zinit; args.fini = zfini; args.align = keg->uk_align; args.flags = keg->uk_flags | UMA_ZONE_SECONDARY; args.keg = keg; if (booted < BOOT_BUCKETS) { locked = false; } else { sx_slock(&uma_reclaim_lock); locked = true; } /* XXX Attaches only one keg of potentially many. */ res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK); if (locked) sx_sunlock(&uma_reclaim_lock); return (res); } /* See uma.h */ uma_zone_t uma_zcache_create(char *name, int size, uma_ctor ctor, uma_dtor dtor, uma_init zinit, uma_fini zfini, uma_import zimport, uma_release zrelease, void *arg, int flags) { struct uma_zctor_args args; memset(&args, 0, sizeof(args)); args.name = name; args.size = size; args.ctor = ctor; args.dtor = dtor; args.uminit = zinit; args.fini = zfini; args.import = zimport; args.release = zrelease; args.arg = arg; args.align = 0; args.flags = flags | UMA_ZFLAG_CACHE; return (zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK)); } /* See uma.h */ void uma_zdestroy(uma_zone_t zone) { sx_slock(&uma_reclaim_lock); zone_free_item(zones, zone, NULL, SKIP_NONE); sx_sunlock(&uma_reclaim_lock); } void uma_zwait(uma_zone_t zone) { void *item; item = uma_zalloc_arg(zone, NULL, M_WAITOK); uma_zfree(zone, item); } void * uma_zalloc_pcpu_arg(uma_zone_t zone, void *udata, int flags) { void *item; #ifdef SMP int i; MPASS(zone->uz_flags & UMA_ZONE_PCPU); #endif item = uma_zalloc_arg(zone, udata, flags & ~M_ZERO); if (item != NULL && (flags & M_ZERO)) { #ifdef SMP for (i = 0; i <= mp_maxid; i++) bzero(zpcpu_get_cpu(item, i), zone->uz_size); #else bzero(item, zone->uz_size); #endif } return (item); } /* * A stub while both regular and pcpu cases are identical. */ void uma_zfree_pcpu_arg(uma_zone_t zone, void *item, void *udata) { #ifdef SMP MPASS(zone->uz_flags & UMA_ZONE_PCPU); #endif uma_zfree_arg(zone, item, udata); } /* See uma.h */ void * uma_zalloc_arg(uma_zone_t zone, void *udata, int flags) { uma_zone_domain_t zdom; uma_bucket_t bucket; uma_cache_t cache; void *item; int cpu, domain, lockfail, maxbucket; #ifdef INVARIANTS bool skipdbg; #endif /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */ random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA); /* This is the fast path allocation */ CTR4(KTR_UMA, "uma_zalloc_arg thread %x zone %s(%p) flags %d", curthread, zone->uz_name, zone, flags); if (flags & M_WAITOK) { WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "uma_zalloc_arg: zone \"%s\"", zone->uz_name); } KASSERT((flags & M_EXEC) == 0, ("uma_zalloc_arg: called with M_EXEC")); KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), ("uma_zalloc_arg: called with spinlock or critical section held")); if (zone->uz_flags & UMA_ZONE_PCPU) KASSERT((flags & M_ZERO) == 0, ("allocating from a pcpu zone " "with M_ZERO passed")); #ifdef DEBUG_MEMGUARD if (memguard_cmp_zone(zone)) { item = memguard_alloc(zone->uz_size, flags); if (item != NULL) { if (zone->uz_init != NULL && zone->uz_init(item, zone->uz_size, flags) != 0) return (NULL); if (zone->uz_ctor != NULL && zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) { zone->uz_fini(item, zone->uz_size); return (NULL); } return (item); } /* This is unfortunate but should not be fatal. */ } #endif /* * If possible, allocate from the per-CPU cache. There are two * requirements for safe access to the per-CPU cache: (1) the thread * accessing the cache must not be preempted or yield during access, * and (2) the thread must not migrate CPUs without switching which * cache it accesses. We rely on a critical section to prevent * preemption and migration. We release the critical section in * order to acquire the zone mutex if we are unable to allocate from * the current cache; when we re-acquire the critical section, we * must detect and handle migration if it has occurred. */ zalloc_restart: critical_enter(); cpu = curcpu; cache = &zone->uz_cpu[cpu]; zalloc_start: bucket = cache->uc_allocbucket; if (bucket != NULL && bucket->ub_cnt > 0) { bucket->ub_cnt--; item = bucket->ub_bucket[bucket->ub_cnt]; #ifdef INVARIANTS bucket->ub_bucket[bucket->ub_cnt] = NULL; #endif KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled.")); cache->uc_allocs++; critical_exit(); #ifdef INVARIANTS skipdbg = uma_dbg_zskip(zone, item); #endif if (zone->uz_ctor != NULL && #ifdef INVARIANTS (!skipdbg || zone->uz_ctor != trash_ctor || zone->uz_dtor != trash_dtor) && #endif zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) { counter_u64_add(zone->uz_fails, 1); zone_free_item(zone, item, udata, SKIP_DTOR | SKIP_CNT); return (NULL); } #ifdef INVARIANTS if (!skipdbg) uma_dbg_alloc(zone, NULL, item); #endif if (flags & M_ZERO) uma_zero_item(item, zone); return (item); } /* * We have run out of items in our alloc bucket. * See if we can switch with our free bucket. */ bucket = cache->uc_freebucket; if (bucket != NULL && bucket->ub_cnt > 0) { CTR2(KTR_UMA, "uma_zalloc: zone %s(%p) swapping empty with alloc", zone->uz_name, zone); cache->uc_freebucket = cache->uc_allocbucket; cache->uc_allocbucket = bucket; goto zalloc_start; } /* * Discard any empty allocation bucket while we hold no locks. */ bucket = cache->uc_allocbucket; cache->uc_allocbucket = NULL; critical_exit(); if (bucket != NULL) bucket_free(zone, bucket, udata); /* Short-circuit for zones without buckets and low memory. */ if (zone->uz_count == 0 || bucketdisable) { ZONE_LOCK(zone); if (zone->uz_flags & UMA_ZONE_NUMA) domain = PCPU_GET(domain); else domain = UMA_ANYDOMAIN; goto zalloc_item; } /* * Attempt to retrieve the item from the per-CPU cache has failed, so * we must go back to the zone. This requires the zone lock, so we * must drop the critical section, then re-acquire it when we go back * to the cache. Since the critical section is released, we may be * preempted or migrate. As such, make sure not to maintain any * thread-local state specific to the cache from prior to releasing * the critical section. */ lockfail = 0; if (ZONE_TRYLOCK(zone) == 0) { /* Record contention to size the buckets. */ ZONE_LOCK(zone); lockfail = 1; } critical_enter(); cpu = curcpu; cache = &zone->uz_cpu[cpu]; /* See if we lost the race to fill the cache. */ if (cache->uc_allocbucket != NULL) { ZONE_UNLOCK(zone); goto zalloc_start; } /* * Check the zone's cache of buckets. */ if (zone->uz_flags & UMA_ZONE_NUMA) { domain = PCPU_GET(domain); zdom = &zone->uz_domain[domain]; } else { domain = UMA_ANYDOMAIN; zdom = &zone->uz_domain[0]; } if ((bucket = zone_fetch_bucket(zone, zdom)) != NULL) { KASSERT(bucket->ub_cnt != 0, ("uma_zalloc_arg: Returning an empty bucket.")); cache->uc_allocbucket = bucket; ZONE_UNLOCK(zone); goto zalloc_start; } /* We are no longer associated with this CPU. */ critical_exit(); /* * We bump the uz count when the cache size is insufficient to * handle the working set. */ if (lockfail && zone->uz_count < zone->uz_count_max) zone->uz_count++; if (zone->uz_max_items > 0) { if (zone->uz_items >= zone->uz_max_items) goto zalloc_item; maxbucket = MIN(zone->uz_count, zone->uz_max_items - zone->uz_items); zone->uz_items += maxbucket; } else maxbucket = zone->uz_count; ZONE_UNLOCK(zone); /* * Now lets just fill a bucket and put it on the free list. If that * works we'll restart the allocation from the beginning and it * will use the just filled bucket. */ bucket = zone_alloc_bucket(zone, udata, domain, flags, maxbucket); CTR3(KTR_UMA, "uma_zalloc: zone %s(%p) bucket zone returned %p", zone->uz_name, zone, bucket); ZONE_LOCK(zone); if (bucket != NULL) { if (zone->uz_max_items > 0 && bucket->ub_cnt < maxbucket) { MPASS(zone->uz_items >= maxbucket - bucket->ub_cnt); zone->uz_items -= maxbucket - bucket->ub_cnt; if (zone->uz_sleepers > 0 && zone->uz_items < zone->uz_max_items) wakeup_one(zone); } critical_enter(); cpu = curcpu; cache = &zone->uz_cpu[cpu]; /* * See if we lost the race or were migrated. Cache the * initialized bucket to make this less likely or claim * the memory directly. */ if (cache->uc_allocbucket == NULL && ((zone->uz_flags & UMA_ZONE_NUMA) == 0 || domain == PCPU_GET(domain))) { cache->uc_allocbucket = bucket; zdom->uzd_imax += bucket->ub_cnt; } else if (zone->uz_bkt_count >= zone->uz_bkt_max) { critical_exit(); ZONE_UNLOCK(zone); bucket_drain(zone, bucket); bucket_free(zone, bucket, udata); goto zalloc_restart; } else zone_put_bucket(zone, zdom, bucket, false); ZONE_UNLOCK(zone); goto zalloc_start; } else if (zone->uz_max_items > 0) { zone->uz_items -= maxbucket; if (zone->uz_sleepers > 0 && zone->uz_items + 1 < zone->uz_max_items) wakeup_one(zone); } /* * We may not be able to get a bucket so return an actual item. */ zalloc_item: item = zone_alloc_item_locked(zone, udata, domain, flags); return (item); } void * uma_zalloc_domain(uma_zone_t zone, void *udata, int domain, int flags) { /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */ random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA); /* This is the fast path allocation */ CTR5(KTR_UMA, "uma_zalloc_domain thread %x zone %s(%p) domain %d flags %d", curthread, zone->uz_name, zone, domain, flags); if (flags & M_WAITOK) { WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "uma_zalloc_domain: zone \"%s\"", zone->uz_name); } KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), ("uma_zalloc_domain: called with spinlock or critical section held")); return (zone_alloc_item(zone, udata, domain, flags)); } /* * Find a slab with some space. Prefer slabs that are partially used over those * that are totally full. This helps to reduce fragmentation. * * If 'rr' is 1, search all domains starting from 'domain'. Otherwise check * only 'domain'. */ static uma_slab_t keg_first_slab(uma_keg_t keg, int domain, bool rr) { uma_domain_t dom; uma_slab_t slab; int start; KASSERT(domain >= 0 && domain < vm_ndomains, ("keg_first_slab: domain %d out of range", domain)); KEG_LOCK_ASSERT(keg); slab = NULL; start = domain; do { dom = &keg->uk_domain[domain]; if (!LIST_EMPTY(&dom->ud_part_slab)) return (LIST_FIRST(&dom->ud_part_slab)); if (!LIST_EMPTY(&dom->ud_free_slab)) { slab = LIST_FIRST(&dom->ud_free_slab); LIST_REMOVE(slab, us_link); LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link); return (slab); } if (rr) domain = (domain + 1) % vm_ndomains; } while (domain != start); return (NULL); } static uma_slab_t keg_fetch_free_slab(uma_keg_t keg, int domain, bool rr, int flags) { uint32_t reserve; KEG_LOCK_ASSERT(keg); reserve = (flags & M_USE_RESERVE) != 0 ? 0 : keg->uk_reserve; if (keg->uk_free <= reserve) return (NULL); return (keg_first_slab(keg, domain, rr)); } static uma_slab_t keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int rdomain, const int flags) { struct vm_domainset_iter di; uma_domain_t dom; uma_slab_t slab; int aflags, domain; bool rr; restart: KEG_LOCK_ASSERT(keg); /* * Use the keg's policy if upper layers haven't already specified a * domain (as happens with first-touch zones). * * To avoid races we run the iterator with the keg lock held, but that * means that we cannot allow the vm_domainset layer to sleep. Thus, * clear M_WAITOK and handle low memory conditions locally. */ rr = rdomain == UMA_ANYDOMAIN; if (rr) { aflags = (flags & ~M_WAITOK) | M_NOWAIT; vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain, &aflags); } else { aflags = flags; domain = rdomain; } for (;;) { slab = keg_fetch_free_slab(keg, domain, rr, flags); if (slab != NULL) { MPASS(slab->us_keg == keg); return (slab); } /* * M_NOVM means don't ask at all! */ if (flags & M_NOVM) break; KASSERT(zone->uz_max_items == 0 || zone->uz_items <= zone->uz_max_items, ("%s: zone %p overflow", __func__, zone)); slab = keg_alloc_slab(keg, zone, domain, flags, aflags); /* * If we got a slab here it's safe to mark it partially used * and return. We assume that the caller is going to remove * at least one item. */ if (slab) { MPASS(slab->us_keg == keg); dom = &keg->uk_domain[slab->us_domain]; LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link); return (slab); } KEG_LOCK(keg); if (rr && vm_domainset_iter_policy(&di, &domain) != 0) { if ((flags & M_WAITOK) != 0) { KEG_UNLOCK(keg); vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask); KEG_LOCK(keg); goto restart; } break; } } /* * We might not have been able to get a slab but another cpu * could have while we were unlocked. Check again before we * fail. */ if ((slab = keg_fetch_free_slab(keg, domain, rr, flags)) != NULL) { MPASS(slab->us_keg == keg); return (slab); } return (NULL); } static uma_slab_t zone_fetch_slab(uma_zone_t zone, uma_keg_t keg, int domain, int flags) { uma_slab_t slab; if (keg == NULL) { keg = zone->uz_keg; KEG_LOCK(keg); } for (;;) { slab = keg_fetch_slab(keg, zone, domain, flags); if (slab) return (slab); if (flags & (M_NOWAIT | M_NOVM)) break; } KEG_UNLOCK(keg); return (NULL); } static void * slab_alloc_item(uma_keg_t keg, uma_slab_t slab) { uma_domain_t dom; void *item; uint8_t freei; MPASS(keg == slab->us_keg); KEG_LOCK_ASSERT(keg); freei = BIT_FFS(SLAB_SETSIZE, &slab->us_free) - 1; BIT_CLR(SLAB_SETSIZE, freei, &slab->us_free); item = slab->us_data + (keg->uk_rsize * freei); slab->us_freecount--; keg->uk_free--; /* Move this slab to the full list */ if (slab->us_freecount == 0) { LIST_REMOVE(slab, us_link); dom = &keg->uk_domain[slab->us_domain]; LIST_INSERT_HEAD(&dom->ud_full_slab, slab, us_link); } return (item); } static int zone_import(uma_zone_t zone, void **bucket, int max, int domain, int flags) { uma_slab_t slab; uma_keg_t keg; #ifdef NUMA int stripe; #endif int i; slab = NULL; keg = NULL; /* Try to keep the buckets totally full */ for (i = 0; i < max; ) { if ((slab = zone_fetch_slab(zone, keg, domain, flags)) == NULL) break; keg = slab->us_keg; #ifdef NUMA stripe = howmany(max, vm_ndomains); #endif while (slab->us_freecount && i < max) { bucket[i++] = slab_alloc_item(keg, slab); if (keg->uk_free <= keg->uk_reserve) break; #ifdef NUMA /* * If the zone is striped we pick a new slab for every * N allocations. Eliminating this conditional will * instead pick a new domain for each bucket rather * than stripe within each bucket. The current option * produces more fragmentation and requires more cpu * time but yields better distribution. */ if ((zone->uz_flags & UMA_ZONE_NUMA) == 0 && vm_ndomains > 1 && --stripe == 0) break; #endif } /* Don't block if we allocated any successfully. */ flags &= ~M_WAITOK; flags |= M_NOWAIT; } if (slab != NULL) KEG_UNLOCK(keg); return i; } static uma_bucket_t zone_alloc_bucket(uma_zone_t zone, void *udata, int domain, int flags, int max) { uma_bucket_t bucket; CTR1(KTR_UMA, "zone_alloc:_bucket domain %d)", domain); /* Avoid allocs targeting empty domains. */ if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain)) domain = UMA_ANYDOMAIN; /* Don't wait for buckets, preserve caller's NOVM setting. */ bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM)); if (bucket == NULL) return (NULL); bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket, MIN(max, bucket->ub_entries), domain, flags); /* * Initialize the memory if necessary. */ if (bucket->ub_cnt != 0 && zone->uz_init != NULL) { int i; for (i = 0; i < bucket->ub_cnt; i++) if (zone->uz_init(bucket->ub_bucket[i], zone->uz_size, flags) != 0) break; /* * If we couldn't initialize the whole bucket, put the * rest back onto the freelist. */ if (i != bucket->ub_cnt) { zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i], bucket->ub_cnt - i); #ifdef INVARIANTS bzero(&bucket->ub_bucket[i], sizeof(void *) * (bucket->ub_cnt - i)); #endif bucket->ub_cnt = i; } } if (bucket->ub_cnt == 0) { bucket_free(zone, bucket, udata); counter_u64_add(zone->uz_fails, 1); return (NULL); } return (bucket); } /* * Allocates a single item from a zone. * * Arguments * zone The zone to alloc for. * udata The data to be passed to the constructor. * domain The domain to allocate from or UMA_ANYDOMAIN. * flags M_WAITOK, M_NOWAIT, M_ZERO. * * Returns * NULL if there is no memory and M_NOWAIT is set * An item if successful */ static void * zone_alloc_item(uma_zone_t zone, void *udata, int domain, int flags) { ZONE_LOCK(zone); return (zone_alloc_item_locked(zone, udata, domain, flags)); } /* * Returns with zone unlocked. */ static void * zone_alloc_item_locked(uma_zone_t zone, void *udata, int domain, int flags) { void *item; #ifdef INVARIANTS bool skipdbg; #endif ZONE_LOCK_ASSERT(zone); if (zone->uz_max_items > 0) { if (zone->uz_items >= zone->uz_max_items) { zone_log_warning(zone); zone_maxaction(zone); if (flags & M_NOWAIT) { ZONE_UNLOCK(zone); return (NULL); } zone->uz_sleeps++; zone->uz_sleepers++; while (zone->uz_items >= zone->uz_max_items) mtx_sleep(zone, zone->uz_lockptr, PVM, "zonelimit", 0); zone->uz_sleepers--; if (zone->uz_sleepers > 0 && zone->uz_items + 1 < zone->uz_max_items) wakeup_one(zone); } zone->uz_items++; } ZONE_UNLOCK(zone); /* Avoid allocs targeting empty domains. */ if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain)) domain = UMA_ANYDOMAIN; if (zone->uz_import(zone->uz_arg, &item, 1, domain, flags) != 1) goto fail; #ifdef INVARIANTS skipdbg = uma_dbg_zskip(zone, item); #endif /* * We have to call both the zone's init (not the keg's init) * and the zone's ctor. This is because the item is going from * a keg slab directly to the user, and the user is expecting it * to be both zone-init'd as well as zone-ctor'd. */ if (zone->uz_init != NULL) { if (zone->uz_init(item, zone->uz_size, flags) != 0) { zone_free_item(zone, item, udata, SKIP_FINI | SKIP_CNT); goto fail; } } if (zone->uz_ctor != NULL && #ifdef INVARIANTS (!skipdbg || zone->uz_ctor != trash_ctor || zone->uz_dtor != trash_dtor) && #endif zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) { zone_free_item(zone, item, udata, SKIP_DTOR | SKIP_CNT); goto fail; } #ifdef INVARIANTS if (!skipdbg) uma_dbg_alloc(zone, NULL, item); #endif if (flags & M_ZERO) uma_zero_item(item, zone); counter_u64_add(zone->uz_allocs, 1); CTR3(KTR_UMA, "zone_alloc_item item %p from %s(%p)", item, zone->uz_name, zone); return (item); fail: if (zone->uz_max_items > 0) { ZONE_LOCK(zone); zone->uz_items--; ZONE_UNLOCK(zone); } counter_u64_add(zone->uz_fails, 1); CTR2(KTR_UMA, "zone_alloc_item failed from %s(%p)", zone->uz_name, zone); return (NULL); } /* See uma.h */ void uma_zfree_arg(uma_zone_t zone, void *item, void *udata) { uma_cache_t cache; uma_bucket_t bucket; uma_zone_domain_t zdom; int cpu, domain; #ifdef UMA_XDOMAIN int itemdomain; #endif bool lockfail; #ifdef INVARIANTS bool skipdbg; #endif /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */ random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA); CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread, zone->uz_name); KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), ("uma_zfree_arg: called with spinlock or critical section held")); /* uma_zfree(..., NULL) does nothing, to match free(9). */ if (item == NULL) return; #ifdef DEBUG_MEMGUARD if (is_memguard_addr(item)) { if (zone->uz_dtor != NULL) zone->uz_dtor(item, zone->uz_size, udata); if (zone->uz_fini != NULL) zone->uz_fini(item, zone->uz_size); memguard_free(item); return; } #endif #ifdef INVARIANTS skipdbg = uma_dbg_zskip(zone, item); if (skipdbg == false) { if (zone->uz_flags & UMA_ZONE_MALLOC) uma_dbg_free(zone, udata, item); else uma_dbg_free(zone, NULL, item); } if (zone->uz_dtor != NULL && (!skipdbg || zone->uz_dtor != trash_dtor || zone->uz_ctor != trash_ctor)) #else if (zone->uz_dtor != NULL) #endif zone->uz_dtor(item, zone->uz_size, udata); /* * The race here is acceptable. If we miss it we'll just have to wait * a little longer for the limits to be reset. */ if (zone->uz_sleepers > 0) goto zfree_item; #ifdef UMA_XDOMAIN if ((zone->uz_flags & UMA_ZONE_NUMA) != 0) itemdomain = _vm_phys_domain(pmap_kextract((vm_offset_t)item)); #endif /* * If possible, free to the per-CPU cache. There are two * requirements for safe access to the per-CPU cache: (1) the thread * accessing the cache must not be preempted or yield during access, * and (2) the thread must not migrate CPUs without switching which * cache it accesses. We rely on a critical section to prevent * preemption and migration. We release the critical section in * order to acquire the zone mutex if we are unable to free to the * current cache; when we re-acquire the critical section, we must * detect and handle migration if it has occurred. */ zfree_restart: critical_enter(); cpu = curcpu; cache = &zone->uz_cpu[cpu]; zfree_start: domain = PCPU_GET(domain); #ifdef UMA_XDOMAIN if ((zone->uz_flags & UMA_ZONE_NUMA) == 0) itemdomain = domain; #endif /* * Try to free into the allocbucket first to give LIFO ordering * for cache-hot datastructures. Spill over into the freebucket * if necessary. Alloc will swap them if one runs dry. */ #ifdef UMA_XDOMAIN if (domain != itemdomain) { bucket = cache->uc_crossbucket; } else #endif { bucket = cache->uc_allocbucket; if (bucket == NULL || bucket->ub_cnt >= bucket->ub_entries) bucket = cache->uc_freebucket; } if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) { KASSERT(bucket->ub_bucket[bucket->ub_cnt] == NULL, ("uma_zfree: Freeing to non free bucket index.")); bucket->ub_bucket[bucket->ub_cnt] = item; bucket->ub_cnt++; cache->uc_frees++; critical_exit(); return; } /* * We must go back the zone, which requires acquiring the zone lock, * which in turn means we must release and re-acquire the critical * section. Since the critical section is released, we may be * preempted or migrate. As such, make sure not to maintain any * thread-local state specific to the cache from prior to releasing * the critical section. */ critical_exit(); if (zone->uz_count == 0 || bucketdisable) goto zfree_item; lockfail = false; if (ZONE_TRYLOCK(zone) == 0) { /* Record contention to size the buckets. */ ZONE_LOCK(zone); lockfail = true; } critical_enter(); cpu = curcpu; domain = PCPU_GET(domain); cache = &zone->uz_cpu[cpu]; #ifdef UMA_XDOMAIN if (domain != itemdomain) bucket = cache->uc_crossbucket; else #endif bucket = cache->uc_freebucket; if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) { ZONE_UNLOCK(zone); goto zfree_start; } #ifdef UMA_XDOMAIN if (domain != itemdomain) cache->uc_crossbucket = NULL; else #endif cache->uc_freebucket = NULL; /* We are no longer associated with this CPU. */ critical_exit(); #ifdef UMA_XDOMAIN if (domain != itemdomain) { if (bucket != NULL) { zone->uz_xdomain += bucket->ub_cnt; if (vm_ndomains > 2 || zone->uz_bkt_count >= zone->uz_bkt_max) { ZONE_UNLOCK(zone); bucket_drain(zone, bucket); bucket_free(zone, bucket, udata); } else { zdom = &zone->uz_domain[itemdomain]; zone_put_bucket(zone, zdom, bucket, true); ZONE_UNLOCK(zone); } } else ZONE_UNLOCK(zone); bucket = bucket_alloc(zone, udata, M_NOWAIT); if (bucket == NULL) goto zfree_item; critical_enter(); cpu = curcpu; cache = &zone->uz_cpu[cpu]; if (cache->uc_crossbucket == NULL) { cache->uc_crossbucket = bucket; goto zfree_start; } critical_exit(); bucket_free(zone, bucket, udata); goto zfree_restart; } #endif if ((zone->uz_flags & UMA_ZONE_NUMA) != 0) { zdom = &zone->uz_domain[domain]; } else { domain = 0; zdom = &zone->uz_domain[0]; } /* Can we throw this on the zone full list? */ if (bucket != NULL) { CTR3(KTR_UMA, "uma_zfree: zone %s(%p) putting bucket %p on free list", zone->uz_name, zone, bucket); /* ub_cnt is pointing to the last free item */ KASSERT(bucket->ub_cnt == bucket->ub_entries, ("uma_zfree: Attempting to insert not full bucket onto the full list.\n")); if (zone->uz_bkt_count >= zone->uz_bkt_max) { ZONE_UNLOCK(zone); bucket_drain(zone, bucket); bucket_free(zone, bucket, udata); goto zfree_restart; } else zone_put_bucket(zone, zdom, bucket, true); } /* * We bump the uz count when the cache size is insufficient to * handle the working set. */ if (lockfail && zone->uz_count < zone->uz_count_max) zone->uz_count++; ZONE_UNLOCK(zone); bucket = bucket_alloc(zone, udata, M_NOWAIT); CTR3(KTR_UMA, "uma_zfree: zone %s(%p) allocated bucket %p", zone->uz_name, zone, bucket); if (bucket) { critical_enter(); cpu = curcpu; cache = &zone->uz_cpu[cpu]; if (cache->uc_freebucket == NULL && ((zone->uz_flags & UMA_ZONE_NUMA) == 0 || domain == PCPU_GET(domain))) { cache->uc_freebucket = bucket; goto zfree_start; } /* * We lost the race, start over. We have to drop our * critical section to free the bucket. */ critical_exit(); bucket_free(zone, bucket, udata); goto zfree_restart; } /* * If nothing else caught this, we'll just do an internal free. */ zfree_item: zone_free_item(zone, item, udata, SKIP_DTOR); } void uma_zfree_domain(uma_zone_t zone, void *item, void *udata) { /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */ random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA); CTR2(KTR_UMA, "uma_zfree_domain thread %x zone %s", curthread, zone->uz_name); KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), ("uma_zfree_domain: called with spinlock or critical section held")); /* uma_zfree(..., NULL) does nothing, to match free(9). */ if (item == NULL) return; zone_free_item(zone, item, udata, SKIP_NONE); } static void slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item) { uma_keg_t keg; uma_domain_t dom; uint8_t freei; keg = zone->uz_keg; MPASS(zone->uz_lockptr == &keg->uk_lock); KEG_LOCK_ASSERT(keg); MPASS(keg == slab->us_keg); dom = &keg->uk_domain[slab->us_domain]; /* Do we need to remove from any lists? */ if (slab->us_freecount+1 == keg->uk_ipers) { LIST_REMOVE(slab, us_link); LIST_INSERT_HEAD(&dom->ud_free_slab, slab, us_link); } else if (slab->us_freecount == 0) { LIST_REMOVE(slab, us_link); LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link); } /* Slab management. */ freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize; BIT_SET(SLAB_SETSIZE, freei, &slab->us_free); slab->us_freecount++; /* Keg statistics. */ keg->uk_free++; } static void zone_release(uma_zone_t zone, void **bucket, int cnt) { void *item; uma_slab_t slab; uma_keg_t keg; uint8_t *mem; int i; keg = zone->uz_keg; KEG_LOCK(keg); for (i = 0; i < cnt; i++) { item = bucket[i]; if (!(zone->uz_flags & UMA_ZONE_VTOSLAB)) { mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK)); if (zone->uz_flags & UMA_ZONE_HASH) { slab = hash_sfind(&keg->uk_hash, mem); } else { mem += keg->uk_pgoff; slab = (uma_slab_t)mem; } } else { slab = vtoslab((vm_offset_t)item); MPASS(slab->us_keg == keg); } slab_free_item(zone, slab, item); } KEG_UNLOCK(keg); } /* * Frees a single item to any zone. * * Arguments: * zone The zone to free to * item The item we're freeing * udata User supplied data for the dtor * skip Skip dtors and finis */ static void zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip) { #ifdef INVARIANTS bool skipdbg; skipdbg = uma_dbg_zskip(zone, item); if (skip == SKIP_NONE && !skipdbg) { if (zone->uz_flags & UMA_ZONE_MALLOC) uma_dbg_free(zone, udata, item); else uma_dbg_free(zone, NULL, item); } if (skip < SKIP_DTOR && zone->uz_dtor != NULL && (!skipdbg || zone->uz_dtor != trash_dtor || zone->uz_ctor != trash_ctor)) #else if (skip < SKIP_DTOR && zone->uz_dtor != NULL) #endif zone->uz_dtor(item, zone->uz_size, udata); if (skip < SKIP_FINI && zone->uz_fini) zone->uz_fini(item, zone->uz_size); zone->uz_release(zone->uz_arg, &item, 1); if (skip & SKIP_CNT) return; counter_u64_add(zone->uz_frees, 1); if (zone->uz_max_items > 0) { ZONE_LOCK(zone); zone->uz_items--; if (zone->uz_sleepers > 0 && zone->uz_items < zone->uz_max_items) wakeup_one(zone); ZONE_UNLOCK(zone); } } /* See uma.h */ int uma_zone_set_max(uma_zone_t zone, int nitems) { struct uma_bucket_zone *ubz; + int count; - /* - * If limit is very low we may need to limit how - * much items are allowed in CPU caches. - */ - ubz = &bucket_zones[0]; - for (; ubz->ubz_entries != 0; ubz++) - if (ubz->ubz_entries * 2 * mp_ncpus > nitems) - break; - if (ubz == &bucket_zones[0]) - nitems = ubz->ubz_entries * 2 * mp_ncpus; - else - ubz--; - ZONE_LOCK(zone); - zone->uz_count_max = zone->uz_count = ubz->ubz_entries; + ubz = bucket_zone_max(zone, nitems); + count = ubz != NULL ? ubz->ubz_entries : 0; + zone->uz_count_max = zone->uz_count = count; if (zone->uz_count_min > zone->uz_count_max) zone->uz_count_min = zone->uz_count_max; zone->uz_max_items = nitems; ZONE_UNLOCK(zone); return (nitems); } /* See uma.h */ -int +void uma_zone_set_maxcache(uma_zone_t zone, int nitems) { + struct uma_bucket_zone *ubz; + int bpcpu; ZONE_LOCK(zone); + ubz = bucket_zone_max(zone, nitems); + if (ubz != NULL) { + bpcpu = 2; +#ifdef UMA_XDOMAIN + if ((zone->uz_flags & UMA_ZONE_NUMA) != 0) + /* Count the cross-domain bucket. */ + bpcpu++; +#endif + nitems -= ubz->ubz_entries * bpcpu * mp_ncpus; + zone->uz_count_max = ubz->ubz_entries; + } else { + zone->uz_count_max = zone->uz_count = 0; + } + if (zone->uz_count_min > zone->uz_count_max) + zone->uz_count_min = zone->uz_count_max; zone->uz_bkt_max = nitems; ZONE_UNLOCK(zone); - - return (nitems); } /* See uma.h */ int uma_zone_get_max(uma_zone_t zone) { int nitems; ZONE_LOCK(zone); nitems = zone->uz_max_items; ZONE_UNLOCK(zone); return (nitems); } /* See uma.h */ void uma_zone_set_warning(uma_zone_t zone, const char *warning) { ZONE_LOCK(zone); zone->uz_warning = warning; ZONE_UNLOCK(zone); } /* See uma.h */ void uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction) { ZONE_LOCK(zone); TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone); ZONE_UNLOCK(zone); } /* See uma.h */ int uma_zone_get_cur(uma_zone_t zone) { int64_t nitems; u_int i; ZONE_LOCK(zone); nitems = counter_u64_fetch(zone->uz_allocs) - counter_u64_fetch(zone->uz_frees); CPU_FOREACH(i) { /* * See the comment in uma_vm_zone_stats() regarding the * safety of accessing the per-cpu caches. With the zone lock * held, it is safe, but can potentially result in stale data. */ nitems += zone->uz_cpu[i].uc_allocs - zone->uz_cpu[i].uc_frees; } ZONE_UNLOCK(zone); return (nitems < 0 ? 0 : nitems); } /* See uma.h */ void uma_zone_set_init(uma_zone_t zone, uma_init uminit) { uma_keg_t keg; KEG_GET(zone, keg); KEG_LOCK(keg); KASSERT(keg->uk_pages == 0, ("uma_zone_set_init on non-empty keg")); keg->uk_init = uminit; KEG_UNLOCK(keg); } /* See uma.h */ void uma_zone_set_fini(uma_zone_t zone, uma_fini fini) { uma_keg_t keg; KEG_GET(zone, keg); KEG_LOCK(keg); KASSERT(keg->uk_pages == 0, ("uma_zone_set_fini on non-empty keg")); keg->uk_fini = fini; KEG_UNLOCK(keg); } /* See uma.h */ void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit) { ZONE_LOCK(zone); KASSERT(zone->uz_keg->uk_pages == 0, ("uma_zone_set_zinit on non-empty keg")); zone->uz_init = zinit; ZONE_UNLOCK(zone); } /* See uma.h */ void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini) { ZONE_LOCK(zone); KASSERT(zone->uz_keg->uk_pages == 0, ("uma_zone_set_zfini on non-empty keg")); zone->uz_fini = zfini; ZONE_UNLOCK(zone); } /* See uma.h */ /* XXX uk_freef is not actually used with the zone locked */ void uma_zone_set_freef(uma_zone_t zone, uma_free freef) { uma_keg_t keg; KEG_GET(zone, keg); KASSERT(keg != NULL, ("uma_zone_set_freef: Invalid zone type")); KEG_LOCK(keg); keg->uk_freef = freef; KEG_UNLOCK(keg); } /* See uma.h */ /* XXX uk_allocf is not actually used with the zone locked */ void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf) { uma_keg_t keg; KEG_GET(zone, keg); KEG_LOCK(keg); keg->uk_allocf = allocf; KEG_UNLOCK(keg); } /* See uma.h */ void uma_zone_reserve(uma_zone_t zone, int items) { uma_keg_t keg; KEG_GET(zone, keg); KEG_LOCK(keg); keg->uk_reserve = items; KEG_UNLOCK(keg); } /* See uma.h */ int uma_zone_reserve_kva(uma_zone_t zone, int count) { uma_keg_t keg; vm_offset_t kva; u_int pages; KEG_GET(zone, keg); pages = count / keg->uk_ipers; if (pages * keg->uk_ipers < count) pages++; pages *= keg->uk_ppera; #ifdef UMA_MD_SMALL_ALLOC if (keg->uk_ppera > 1) { #else if (1) { #endif kva = kva_alloc((vm_size_t)pages * PAGE_SIZE); if (kva == 0) return (0); } else kva = 0; ZONE_LOCK(zone); MPASS(keg->uk_kva == 0); keg->uk_kva = kva; keg->uk_offset = 0; zone->uz_max_items = pages * keg->uk_ipers; #ifdef UMA_MD_SMALL_ALLOC keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc; #else keg->uk_allocf = noobj_alloc; #endif keg->uk_flags |= UMA_ZONE_NOFREE; ZONE_UNLOCK(zone); return (1); } /* See uma.h */ void uma_prealloc(uma_zone_t zone, int items) { struct vm_domainset_iter di; uma_domain_t dom; uma_slab_t slab; uma_keg_t keg; int aflags, domain, slabs; KEG_GET(zone, keg); KEG_LOCK(keg); slabs = items / keg->uk_ipers; if (slabs * keg->uk_ipers < items) slabs++; while (slabs-- > 0) { aflags = M_NOWAIT; vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain, &aflags); for (;;) { slab = keg_alloc_slab(keg, zone, domain, M_WAITOK, aflags); if (slab != NULL) { MPASS(slab->us_keg == keg); dom = &keg->uk_domain[slab->us_domain]; LIST_INSERT_HEAD(&dom->ud_free_slab, slab, us_link); break; } KEG_LOCK(keg); if (vm_domainset_iter_policy(&di, &domain) != 0) { KEG_UNLOCK(keg); vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask); KEG_LOCK(keg); } } } KEG_UNLOCK(keg); } /* See uma.h */ void uma_reclaim(int req) { CTR0(KTR_UMA, "UMA: vm asked us to release pages!"); sx_xlock(&uma_reclaim_lock); bucket_enable(); switch (req) { case UMA_RECLAIM_TRIM: zone_foreach(zone_trim); break; case UMA_RECLAIM_DRAIN: case UMA_RECLAIM_DRAIN_CPU: zone_foreach(zone_drain); if (req == UMA_RECLAIM_DRAIN_CPU) { pcpu_cache_drain_safe(NULL); zone_foreach(zone_drain); } break; default: panic("unhandled reclamation request %d", req); } /* * Some slabs may have been freed but this zone will be visited early * we visit again so that we can free pages that are empty once other * zones are drained. We have to do the same for buckets. */ zone_drain(slabzone); bucket_zone_drain(); sx_xunlock(&uma_reclaim_lock); } static volatile int uma_reclaim_needed; void uma_reclaim_wakeup(void) { if (atomic_fetchadd_int(&uma_reclaim_needed, 1) == 0) wakeup(uma_reclaim); } void uma_reclaim_worker(void *arg __unused) { for (;;) { sx_xlock(&uma_reclaim_lock); while (atomic_load_int(&uma_reclaim_needed) == 0) sx_sleep(uma_reclaim, &uma_reclaim_lock, PVM, "umarcl", hz); sx_xunlock(&uma_reclaim_lock); EVENTHANDLER_INVOKE(vm_lowmem, VM_LOW_KMEM); uma_reclaim(UMA_RECLAIM_DRAIN_CPU); atomic_store_int(&uma_reclaim_needed, 0); /* Don't fire more than once per-second. */ pause("umarclslp", hz); } } /* See uma.h */ void uma_zone_reclaim(uma_zone_t zone, int req) { switch (req) { case UMA_RECLAIM_TRIM: zone_trim(zone); break; case UMA_RECLAIM_DRAIN: zone_drain(zone); break; case UMA_RECLAIM_DRAIN_CPU: pcpu_cache_drain_safe(zone); zone_drain(zone); break; default: panic("unhandled reclamation request %d", req); } } /* See uma.h */ int uma_zone_exhausted(uma_zone_t zone) { int full; ZONE_LOCK(zone); full = zone->uz_sleepers > 0; ZONE_UNLOCK(zone); return (full); } int uma_zone_exhausted_nolock(uma_zone_t zone) { return (zone->uz_sleepers > 0); } void * uma_large_malloc_domain(vm_size_t size, int domain, int wait) { struct domainset *policy; vm_offset_t addr; uma_slab_t slab; if (domain != UMA_ANYDOMAIN) { /* avoid allocs targeting empty domains */ if (VM_DOMAIN_EMPTY(domain)) domain = UMA_ANYDOMAIN; } slab = zone_alloc_item(slabzone, NULL, domain, wait); if (slab == NULL) return (NULL); policy = (domain == UMA_ANYDOMAIN) ? DOMAINSET_RR() : DOMAINSET_FIXED(domain); addr = kmem_malloc_domainset(policy, size, wait); if (addr != 0) { vsetslab(addr, slab); slab->us_data = (void *)addr; slab->us_flags = UMA_SLAB_KERNEL | UMA_SLAB_MALLOC; slab->us_size = size; slab->us_domain = vm_phys_domain(PHYS_TO_VM_PAGE( pmap_kextract(addr))); uma_total_inc(size); } else { zone_free_item(slabzone, slab, NULL, SKIP_NONE); } return ((void *)addr); } void * uma_large_malloc(vm_size_t size, int wait) { return uma_large_malloc_domain(size, UMA_ANYDOMAIN, wait); } void uma_large_free(uma_slab_t slab) { KASSERT((slab->us_flags & UMA_SLAB_KERNEL) != 0, ("uma_large_free: Memory not allocated with uma_large_malloc.")); kmem_free((vm_offset_t)slab->us_data, slab->us_size); uma_total_dec(slab->us_size); zone_free_item(slabzone, slab, NULL, SKIP_NONE); } static void uma_zero_item(void *item, uma_zone_t zone) { bzero(item, zone->uz_size); } unsigned long uma_limit(void) { return (uma_kmem_limit); } void uma_set_limit(unsigned long limit) { uma_kmem_limit = limit; } unsigned long uma_size(void) { return (atomic_load_long(&uma_kmem_total)); } long uma_avail(void) { return (uma_kmem_limit - uma_size()); } void uma_print_stats(void) { zone_foreach(uma_print_zone); } static void slab_print(uma_slab_t slab) { printf("slab: keg %p, data %p, freecount %d\n", slab->us_keg, slab->us_data, slab->us_freecount); } static void cache_print(uma_cache_t cache) { printf("alloc: %p(%d), free: %p(%d), cross: %p(%d)j\n", cache->uc_allocbucket, cache->uc_allocbucket?cache->uc_allocbucket->ub_cnt:0, cache->uc_freebucket, cache->uc_freebucket?cache->uc_freebucket->ub_cnt:0, cache->uc_crossbucket, cache->uc_crossbucket?cache->uc_crossbucket->ub_cnt:0); } static void uma_print_keg(uma_keg_t keg) { uma_domain_t dom; uma_slab_t slab; int i; printf("keg: %s(%p) size %d(%d) flags %#x ipers %d ppera %d " "out %d free %d\n", keg->uk_name, keg, keg->uk_size, keg->uk_rsize, keg->uk_flags, keg->uk_ipers, keg->uk_ppera, (keg->uk_pages / keg->uk_ppera) * keg->uk_ipers - keg->uk_free, keg->uk_free); for (i = 0; i < vm_ndomains; i++) { dom = &keg->uk_domain[i]; printf("Part slabs:\n"); LIST_FOREACH(slab, &dom->ud_part_slab, us_link) slab_print(slab); printf("Free slabs:\n"); LIST_FOREACH(slab, &dom->ud_free_slab, us_link) slab_print(slab); printf("Full slabs:\n"); LIST_FOREACH(slab, &dom->ud_full_slab, us_link) slab_print(slab); } } void uma_print_zone(uma_zone_t zone) { uma_cache_t cache; int i; printf("zone: %s(%p) size %d maxitems %ju flags %#x\n", zone->uz_name, zone, zone->uz_size, (uintmax_t)zone->uz_max_items, zone->uz_flags); if (zone->uz_lockptr != &zone->uz_lock) uma_print_keg(zone->uz_keg); CPU_FOREACH(i) { cache = &zone->uz_cpu[i]; printf("CPU %d Cache:\n", i); cache_print(cache); } } #ifdef DDB /* * Generate statistics across both the zone and its per-cpu cache's. Return * desired statistics if the pointer is non-NULL for that statistic. * * Note: does not update the zone statistics, as it can't safely clear the * per-CPU cache statistic. * * XXXRW: Following the uc_allocbucket and uc_freebucket pointers here isn't * safe from off-CPU; we should modify the caches to track this information * directly so that we don't have to. */ static void uma_zone_sumstat(uma_zone_t z, long *cachefreep, uint64_t *allocsp, uint64_t *freesp, uint64_t *sleepsp, uint64_t *xdomainp) { uma_cache_t cache; uint64_t allocs, frees, sleeps, xdomain; int cachefree, cpu; allocs = frees = sleeps = xdomain = 0; cachefree = 0; CPU_FOREACH(cpu) { cache = &z->uz_cpu[cpu]; if (cache->uc_allocbucket != NULL) cachefree += cache->uc_allocbucket->ub_cnt; if (cache->uc_freebucket != NULL) cachefree += cache->uc_freebucket->ub_cnt; if (cache->uc_crossbucket != NULL) { xdomain += cache->uc_crossbucket->ub_cnt; cachefree += cache->uc_crossbucket->ub_cnt; } allocs += cache->uc_allocs; frees += cache->uc_frees; } allocs += counter_u64_fetch(z->uz_allocs); frees += counter_u64_fetch(z->uz_frees); sleeps += z->uz_sleeps; xdomain += z->uz_xdomain; if (cachefreep != NULL) *cachefreep = cachefree; if (allocsp != NULL) *allocsp = allocs; if (freesp != NULL) *freesp = frees; if (sleepsp != NULL) *sleepsp = sleeps; if (xdomainp != NULL) *xdomainp = xdomain; } #endif /* DDB */ static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS) { uma_keg_t kz; uma_zone_t z; int count; count = 0; rw_rlock(&uma_rwlock); LIST_FOREACH(kz, &uma_kegs, uk_link) { LIST_FOREACH(z, &kz->uk_zones, uz_link) count++; } LIST_FOREACH(z, &uma_cachezones, uz_link) count++; rw_runlock(&uma_rwlock); return (sysctl_handle_int(oidp, &count, 0, req)); } static void uma_vm_zone_stats(struct uma_type_header *uth, uma_zone_t z, struct sbuf *sbuf, struct uma_percpu_stat *ups, bool internal) { uma_zone_domain_t zdom; uma_bucket_t bucket; uma_cache_t cache; int i; for (i = 0; i < vm_ndomains; i++) { zdom = &z->uz_domain[i]; uth->uth_zone_free += zdom->uzd_nitems; } uth->uth_allocs = counter_u64_fetch(z->uz_allocs); uth->uth_frees = counter_u64_fetch(z->uz_frees); uth->uth_fails = counter_u64_fetch(z->uz_fails); uth->uth_sleeps = z->uz_sleeps; uth->uth_xdomain = z->uz_xdomain; /* * While it is not normally safe to access the cache bucket pointers * while not on the CPU that owns the cache, we only allow the pointers * to be exchanged without the zone lock held, not invalidated, so * accept the possible race associated with bucket exchange during * monitoring. Use atomic_load_ptr() to ensure that the bucket pointers * are loaded only once. */ for (i = 0; i < mp_maxid + 1; i++) { bzero(&ups[i], sizeof(*ups)); if (internal || CPU_ABSENT(i)) continue; cache = &z->uz_cpu[i]; bucket = (uma_bucket_t)atomic_load_ptr(&cache->uc_allocbucket); if (bucket != NULL) ups[i].ups_cache_free += bucket->ub_cnt; bucket = (uma_bucket_t)atomic_load_ptr(&cache->uc_freebucket); if (bucket != NULL) ups[i].ups_cache_free += bucket->ub_cnt; bucket = (uma_bucket_t)atomic_load_ptr(&cache->uc_crossbucket); if (bucket != NULL) ups[i].ups_cache_free += bucket->ub_cnt; ups[i].ups_allocs = cache->uc_allocs; ups[i].ups_frees = cache->uc_frees; } } static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS) { struct uma_stream_header ush; struct uma_type_header uth; struct uma_percpu_stat *ups; struct sbuf sbuf; uma_keg_t kz; uma_zone_t z; int count, error, i; error = sysctl_wire_old_buffer(req, 0); if (error != 0) return (error); sbuf_new_for_sysctl(&sbuf, NULL, 128, req); sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL); ups = malloc((mp_maxid + 1) * sizeof(*ups), M_TEMP, M_WAITOK); count = 0; rw_rlock(&uma_rwlock); LIST_FOREACH(kz, &uma_kegs, uk_link) { LIST_FOREACH(z, &kz->uk_zones, uz_link) count++; } LIST_FOREACH(z, &uma_cachezones, uz_link) count++; /* * Insert stream header. */ bzero(&ush, sizeof(ush)); ush.ush_version = UMA_STREAM_VERSION; ush.ush_maxcpus = (mp_maxid + 1); ush.ush_count = count; (void)sbuf_bcat(&sbuf, &ush, sizeof(ush)); LIST_FOREACH(kz, &uma_kegs, uk_link) { LIST_FOREACH(z, &kz->uk_zones, uz_link) { bzero(&uth, sizeof(uth)); ZONE_LOCK(z); strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME); uth.uth_align = kz->uk_align; uth.uth_size = kz->uk_size; uth.uth_rsize = kz->uk_rsize; if (z->uz_max_items > 0) uth.uth_pages = (z->uz_items / kz->uk_ipers) * kz->uk_ppera; else uth.uth_pages = kz->uk_pages; uth.uth_maxpages = (z->uz_max_items / kz->uk_ipers) * kz->uk_ppera; uth.uth_limit = z->uz_max_items; uth.uth_keg_free = z->uz_keg->uk_free; /* * A zone is secondary is it is not the first entry * on the keg's zone list. */ if ((z->uz_flags & UMA_ZONE_SECONDARY) && (LIST_FIRST(&kz->uk_zones) != z)) uth.uth_zone_flags = UTH_ZONE_SECONDARY; uma_vm_zone_stats(&uth, z, &sbuf, ups, kz->uk_flags & UMA_ZFLAG_INTERNAL); ZONE_UNLOCK(z); (void)sbuf_bcat(&sbuf, &uth, sizeof(uth)); for (i = 0; i < mp_maxid + 1; i++) (void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i])); } } LIST_FOREACH(z, &uma_cachezones, uz_link) { bzero(&uth, sizeof(uth)); ZONE_LOCK(z); strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME); uth.uth_size = z->uz_size; uma_vm_zone_stats(&uth, z, &sbuf, ups, false); ZONE_UNLOCK(z); (void)sbuf_bcat(&sbuf, &uth, sizeof(uth)); for (i = 0; i < mp_maxid + 1; i++) (void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i])); } rw_runlock(&uma_rwlock); error = sbuf_finish(&sbuf); sbuf_delete(&sbuf); free(ups, M_TEMP); return (error); } int sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS) { uma_zone_t zone = *(uma_zone_t *)arg1; int error, max; max = uma_zone_get_max(zone); error = sysctl_handle_int(oidp, &max, 0, req); if (error || !req->newptr) return (error); uma_zone_set_max(zone, max); return (0); } int sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS) { uma_zone_t zone = *(uma_zone_t *)arg1; int cur; cur = uma_zone_get_cur(zone); return (sysctl_handle_int(oidp, &cur, 0, req)); } #ifdef INVARIANTS static uma_slab_t uma_dbg_getslab(uma_zone_t zone, void *item) { uma_slab_t slab; uma_keg_t keg; uint8_t *mem; mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK)); if (zone->uz_flags & UMA_ZONE_VTOSLAB) { slab = vtoslab((vm_offset_t)mem); } else { /* * It is safe to return the slab here even though the * zone is unlocked because the item's allocation state * essentially holds a reference. */ if (zone->uz_lockptr == &zone->uz_lock) return (NULL); ZONE_LOCK(zone); keg = zone->uz_keg; if (keg->uk_flags & UMA_ZONE_HASH) slab = hash_sfind(&keg->uk_hash, mem); else slab = (uma_slab_t)(mem + keg->uk_pgoff); ZONE_UNLOCK(zone); } return (slab); } static bool uma_dbg_zskip(uma_zone_t zone, void *mem) { if (zone->uz_lockptr == &zone->uz_lock) return (true); return (uma_dbg_kskip(zone->uz_keg, mem)); } static bool uma_dbg_kskip(uma_keg_t keg, void *mem) { uintptr_t idx; if (dbg_divisor == 0) return (true); if (dbg_divisor == 1) return (false); idx = (uintptr_t)mem >> PAGE_SHIFT; if (keg->uk_ipers > 1) { idx *= keg->uk_ipers; idx += ((uintptr_t)mem & PAGE_MASK) / keg->uk_rsize; } if ((idx / dbg_divisor) * dbg_divisor != idx) { counter_u64_add(uma_skip_cnt, 1); return (true); } counter_u64_add(uma_dbg_cnt, 1); return (false); } /* * Set up the slab's freei data such that uma_dbg_free can function. * */ static void uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item) { uma_keg_t keg; int freei; if (slab == NULL) { slab = uma_dbg_getslab(zone, item); if (slab == NULL) panic("uma: item %p did not belong to zone %s\n", item, zone->uz_name); } keg = slab->us_keg; freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize; if (BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree)) panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)\n", item, zone, zone->uz_name, slab, freei); BIT_SET_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree); return; } /* * Verifies freed addresses. Checks for alignment, valid slab membership * and duplicate frees. * */ static void uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item) { uma_keg_t keg; int freei; if (slab == NULL) { slab = uma_dbg_getslab(zone, item); if (slab == NULL) panic("uma: Freed item %p did not belong to zone %s\n", item, zone->uz_name); } keg = slab->us_keg; freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize; if (freei >= keg->uk_ipers) panic("Invalid free of %p from zone %p(%s) slab %p(%d)\n", item, zone, zone->uz_name, slab, freei); if (((freei * keg->uk_rsize) + slab->us_data) != item) panic("Unaligned free of %p from zone %p(%s) slab %p(%d)\n", item, zone, zone->uz_name, slab, freei); if (!BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree)) panic("Duplicate free of %p from zone %p(%s) slab %p(%d)\n", item, zone, zone->uz_name, slab, freei); BIT_CLR_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree); } #endif /* INVARIANTS */ #ifdef DDB static int64_t get_uma_stats(uma_keg_t kz, uma_zone_t z, uint64_t *allocs, uint64_t *used, uint64_t *sleeps, long *cachefree, uint64_t *xdomain) { uint64_t frees; int i; if (kz->uk_flags & UMA_ZFLAG_INTERNAL) { *allocs = counter_u64_fetch(z->uz_allocs); frees = counter_u64_fetch(z->uz_frees); *sleeps = z->uz_sleeps; *cachefree = 0; *xdomain = 0; } else uma_zone_sumstat(z, cachefree, allocs, &frees, sleeps, xdomain); if (!((z->uz_flags & UMA_ZONE_SECONDARY) && (LIST_FIRST(&kz->uk_zones) != z))) *cachefree += kz->uk_free; for (i = 0; i < vm_ndomains; i++) *cachefree += z->uz_domain[i].uzd_nitems; *used = *allocs - frees; return (((int64_t)*used + *cachefree) * kz->uk_size); } DB_SHOW_COMMAND(uma, db_show_uma) { const char *fmt_hdr, *fmt_entry; uma_keg_t kz; uma_zone_t z; uint64_t allocs, used, sleeps, xdomain; long cachefree; /* variables for sorting */ uma_keg_t cur_keg; uma_zone_t cur_zone, last_zone; int64_t cur_size, last_size, size; int ties; /* /i option produces machine-parseable CSV output */ if (modif[0] == 'i') { fmt_hdr = "%s,%s,%s,%s,%s,%s,%s,%s,%s\n"; fmt_entry = "\"%s\",%ju,%jd,%ld,%ju,%ju,%u,%jd,%ju\n"; } else { fmt_hdr = "%18s %6s %7s %7s %11s %7s %7s %10s %8s\n"; fmt_entry = "%18s %6ju %7jd %7ld %11ju %7ju %7u %10jd %8ju\n"; } db_printf(fmt_hdr, "Zone", "Size", "Used", "Free", "Requests", "Sleeps", "Bucket", "Total Mem", "XFree"); /* Sort the zones with largest size first. */ last_zone = NULL; last_size = INT64_MAX; for (;;) { cur_zone = NULL; cur_size = -1; ties = 0; LIST_FOREACH(kz, &uma_kegs, uk_link) { LIST_FOREACH(z, &kz->uk_zones, uz_link) { /* * In the case of size ties, print out zones * in the order they are encountered. That is, * when we encounter the most recently output * zone, we have already printed all preceding * ties, and we must print all following ties. */ if (z == last_zone) { ties = 1; continue; } size = get_uma_stats(kz, z, &allocs, &used, &sleeps, &cachefree, &xdomain); if (size > cur_size && size < last_size + ties) { cur_size = size; cur_zone = z; cur_keg = kz; } } } if (cur_zone == NULL) break; size = get_uma_stats(cur_keg, cur_zone, &allocs, &used, &sleeps, &cachefree, &xdomain); db_printf(fmt_entry, cur_zone->uz_name, (uintmax_t)cur_keg->uk_size, (intmax_t)used, cachefree, (uintmax_t)allocs, (uintmax_t)sleeps, (unsigned)cur_zone->uz_count, (intmax_t)size, xdomain); if (db_pager_quit) return; last_zone = cur_zone; last_size = cur_size; } } DB_SHOW_COMMAND(umacache, db_show_umacache) { uma_zone_t z; uint64_t allocs, frees; long cachefree; int i; db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free", "Requests", "Bucket"); LIST_FOREACH(z, &uma_cachezones, uz_link) { uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL, NULL); for (i = 0; i < vm_ndomains; i++) cachefree += z->uz_domain[i].uzd_nitems; db_printf("%18s %8ju %8jd %8ld %12ju %8u\n", z->uz_name, (uintmax_t)z->uz_size, (intmax_t)(allocs - frees), cachefree, (uintmax_t)allocs, z->uz_count); if (db_pager_quit) return; } } #endif /* DDB */ Index: head/sys/vm/vm_glue.c =================================================================== --- head/sys/vm/vm_glue.c (revision 355001) +++ head/sys/vm/vm_glue.c (revision 355002) @@ -1,602 +1,603 @@ /*- * SPDX-License-Identifier: (BSD-3-Clause AND MIT-CMU) * * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * The Mach Operating System project at Carnegie-Mellon University. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)vm_glue.c 8.6 (Berkeley) 1/5/94 * * * Copyright (c) 1987, 1990 Carnegie-Mellon University. * All rights reserved. * * Permission to use, copy, modify and distribute this software and * its documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. */ #include __FBSDID("$FreeBSD$"); #include "opt_vm.h" #include "opt_kstack_pages.h" #include "opt_kstack_max_pages.h" #include "opt_kstack_usage_prof.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include +#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * MPSAFE * * WARNING! This code calls vm_map_check_protection() which only checks * the associated vm_map_entry range. It does not determine whether the * contents of the memory is actually readable or writable. In most cases * just checking the vm_map_entry is sufficient within the kernel's address * space. */ int kernacc(void *addr, int len, int rw) { boolean_t rv; vm_offset_t saddr, eaddr; vm_prot_t prot; KASSERT((rw & ~VM_PROT_ALL) == 0, ("illegal ``rw'' argument to kernacc (%x)\n", rw)); if ((vm_offset_t)addr + len > vm_map_max(kernel_map) || (vm_offset_t)addr + len < (vm_offset_t)addr) return (FALSE); prot = rw; saddr = trunc_page((vm_offset_t)addr); eaddr = round_page((vm_offset_t)addr + len); vm_map_lock_read(kernel_map); rv = vm_map_check_protection(kernel_map, saddr, eaddr, prot); vm_map_unlock_read(kernel_map); return (rv == TRUE); } /* * MPSAFE * * WARNING! This code calls vm_map_check_protection() which only checks * the associated vm_map_entry range. It does not determine whether the * contents of the memory is actually readable or writable. vmapbuf(), * vm_fault_quick(), or copyin()/copout()/su*()/fu*() functions should be * used in conjunction with this call. */ int useracc(void *addr, int len, int rw) { boolean_t rv; vm_prot_t prot; vm_map_t map; KASSERT((rw & ~VM_PROT_ALL) == 0, ("illegal ``rw'' argument to useracc (%x)\n", rw)); prot = rw; map = &curproc->p_vmspace->vm_map; if ((vm_offset_t)addr + len > vm_map_max(map) || (vm_offset_t)addr + len < (vm_offset_t)addr) { return (FALSE); } vm_map_lock_read(map); rv = vm_map_check_protection(map, trunc_page((vm_offset_t)addr), round_page((vm_offset_t)addr + len), prot); vm_map_unlock_read(map); return (rv == TRUE); } int vslock(void *addr, size_t len) { vm_offset_t end, last, start; vm_size_t npages; int error; last = (vm_offset_t)addr + len; start = trunc_page((vm_offset_t)addr); end = round_page(last); if (last < (vm_offset_t)addr || end < (vm_offset_t)addr) return (EINVAL); npages = atop(end - start); if (npages > vm_page_max_user_wired) return (ENOMEM); error = vm_map_wire(&curproc->p_vmspace->vm_map, start, end, VM_MAP_WIRE_SYSTEM | VM_MAP_WIRE_NOHOLES); if (error == KERN_SUCCESS) { curthread->td_vslock_sz += len; return (0); } /* * Return EFAULT on error to match copy{in,out}() behaviour * rather than returning ENOMEM like mlock() would. */ return (EFAULT); } void vsunlock(void *addr, size_t len) { /* Rely on the parameter sanity checks performed by vslock(). */ MPASS(curthread->td_vslock_sz >= len); curthread->td_vslock_sz -= len; (void)vm_map_unwire(&curproc->p_vmspace->vm_map, trunc_page((vm_offset_t)addr), round_page((vm_offset_t)addr + len), VM_MAP_WIRE_SYSTEM | VM_MAP_WIRE_NOHOLES); } /* * Pin the page contained within the given object at the given offset. If the * page is not resident, allocate and load it using the given object's pager. * Return the pinned page if successful; otherwise, return NULL. */ static vm_page_t vm_imgact_hold_page(vm_object_t object, vm_ooffset_t offset) { vm_page_t m; vm_pindex_t pindex; pindex = OFF_TO_IDX(offset); VM_OBJECT_WLOCK(object); (void)vm_page_grab_valid(&m, object, pindex, VM_ALLOC_NORMAL | VM_ALLOC_NOBUSY | VM_ALLOC_WIRED); VM_OBJECT_WUNLOCK(object); return (m); } /* * Return a CPU private mapping to the page at the given offset within the * given object. The page is pinned before it is mapped. */ struct sf_buf * vm_imgact_map_page(vm_object_t object, vm_ooffset_t offset) { vm_page_t m; m = vm_imgact_hold_page(object, offset); if (m == NULL) return (NULL); sched_pin(); return (sf_buf_alloc(m, SFB_CPUPRIVATE)); } /* * Destroy the given CPU private mapping and unpin the page that it mapped. */ void vm_imgact_unmap_page(struct sf_buf *sf) { vm_page_t m; m = sf_buf_page(sf); sf_buf_free(sf); sched_unpin(); vm_page_unwire(m, PQ_ACTIVE); } void vm_sync_icache(vm_map_t map, vm_offset_t va, vm_offset_t sz) { pmap_sync_icache(map->pmap, va, sz); } static uma_zone_t kstack_cache; -static int kstack_cache_size = 128; +static int kstack_cache_size; static int kstack_domain_iter; static int sysctl_kstack_cache_size(SYSCTL_HANDLER_ARGS) { int error, newsize; newsize = kstack_cache_size; error = sysctl_handle_int(oidp, &newsize, 0, req); if (error == 0 && req->newptr && newsize != kstack_cache_size) - kstack_cache_size = - uma_zone_set_maxcache(kstack_cache, newsize); + uma_zone_set_maxcache(kstack_cache, newsize); return (error); } SYSCTL_PROC(_vm, OID_AUTO, kstack_cache_size, CTLTYPE_INT|CTLFLAG_RW, &kstack_cache_size, 0, sysctl_kstack_cache_size, "IU", "Maximum number of cached kernel stacks"); /* * Create the kernel stack (including pcb for i386) for a new thread. * This routine directly affects the fork perf for a process and * create performance for a thread. */ static vm_offset_t vm_thread_stack_create(struct domainset *ds, vm_object_t *ksobjp, int pages) { vm_page_t ma[KSTACK_MAX_PAGES]; vm_object_t ksobj; vm_offset_t ks; int i; /* * Allocate an object for the kstack. */ ksobj = vm_object_allocate(OBJT_DEFAULT, pages); /* * Get a kernel virtual address for this thread's kstack. */ #if defined(__mips__) /* * We need to align the kstack's mapped address to fit within * a single TLB entry. */ if (vmem_xalloc(kernel_arena, (pages + KSTACK_GUARD_PAGES) * PAGE_SIZE, PAGE_SIZE * 2, 0, 0, VMEM_ADDR_MIN, VMEM_ADDR_MAX, M_BESTFIT | M_NOWAIT, &ks)) { ks = 0; } #else ks = kva_alloc((pages + KSTACK_GUARD_PAGES) * PAGE_SIZE); #endif if (ks == 0) { printf("%s: kstack allocation failed\n", __func__); vm_object_deallocate(ksobj); return (0); } if (vm_ndomains > 1) { ksobj->domain.dr_policy = ds; ksobj->domain.dr_iter = atomic_fetchadd_int(&kstack_domain_iter, 1); } if (KSTACK_GUARD_PAGES != 0) { pmap_qremove(ks, KSTACK_GUARD_PAGES); ks += KSTACK_GUARD_PAGES * PAGE_SIZE; } /* * For the length of the stack, link in a real page of ram for each * page of stack. */ VM_OBJECT_WLOCK(ksobj); (void)vm_page_grab_pages(ksobj, 0, VM_ALLOC_NORMAL | VM_ALLOC_NOBUSY | VM_ALLOC_WIRED, ma, pages); for (i = 0; i < pages; i++) ma[i]->valid = VM_PAGE_BITS_ALL; VM_OBJECT_WUNLOCK(ksobj); pmap_qenter(ks, ma, pages); *ksobjp = ksobj; return (ks); } static void vm_thread_stack_dispose(vm_object_t ksobj, vm_offset_t ks, int pages) { vm_page_t m; int i; pmap_qremove(ks, pages); VM_OBJECT_WLOCK(ksobj); for (i = 0; i < pages; i++) { m = vm_page_lookup(ksobj, i); if (m == NULL) panic("%s: kstack already missing?", __func__); vm_page_unwire_noq(m); vm_page_free(m); } VM_OBJECT_WUNLOCK(ksobj); vm_object_deallocate(ksobj); kva_free(ks - (KSTACK_GUARD_PAGES * PAGE_SIZE), (pages + KSTACK_GUARD_PAGES) * PAGE_SIZE); } /* * Allocate the kernel stack for a new thread. */ int vm_thread_new(struct thread *td, int pages) { vm_object_t ksobj; vm_offset_t ks; /* Bounds check */ if (pages <= 1) pages = kstack_pages; else if (pages > KSTACK_MAX_PAGES) pages = KSTACK_MAX_PAGES; ks = 0; ksobj = NULL; if (pages == kstack_pages && kstack_cache != NULL) { ks = (vm_offset_t)uma_zalloc(kstack_cache, M_NOWAIT); if (ks != 0) ksobj = PHYS_TO_VM_PAGE(pmap_kextract(ks))->object; } /* * Ensure that kstack objects can draw pages from any memory * domain. Otherwise a local memory shortage can block a process * swap-in. */ if (ks == 0) ks = vm_thread_stack_create(DOMAINSET_PREF(PCPU_GET(domain)), &ksobj, pages); if (ks == 0) return (0); td->td_kstack_obj = ksobj; td->td_kstack = ks; td->td_kstack_pages = pages; return (1); } /* * Dispose of a thread's kernel stack. */ void vm_thread_dispose(struct thread *td) { vm_object_t ksobj; vm_offset_t ks; int pages; pages = td->td_kstack_pages; ksobj = td->td_kstack_obj; ks = td->td_kstack; td->td_kstack = 0; td->td_kstack_pages = 0; if (pages == kstack_pages) uma_zfree(kstack_cache, (void *)ks); else vm_thread_stack_dispose(ksobj, ks, pages); } static int kstack_import(void *arg, void **store, int cnt, int domain, int flags) { struct domainset *ds; vm_object_t ksobj; int i; if (domain == UMA_ANYDOMAIN) ds = DOMAINSET_RR(); else ds = DOMAINSET_PREF(domain); for (i = 0; i < cnt; i++) { store[i] = (void *)vm_thread_stack_create(ds, &ksobj, kstack_pages); if (store[i] == NULL) break; } return (i); } static void kstack_release(void *arg, void **store, int cnt) { vm_offset_t ks; int i; for (i = 0; i < cnt; i++) { ks = (vm_offset_t)store[i]; vm_thread_stack_dispose( PHYS_TO_VM_PAGE(pmap_kextract(ks))->object, ks, kstack_pages); } } static void kstack_cache_init(void *null) { kstack_cache = uma_zcache_create("kstack_cache", kstack_pages * PAGE_SIZE, NULL, NULL, NULL, NULL, kstack_import, kstack_release, NULL, - UMA_ZONE_NUMA|UMA_ZONE_MINBUCKET); + UMA_ZONE_NUMA); + kstack_cache_size = imax(128, mp_ncpus * 4); uma_zone_set_maxcache(kstack_cache, kstack_cache_size); } SYSINIT(vm_kstacks, SI_SUB_KTHREAD_INIT, SI_ORDER_ANY, kstack_cache_init, NULL); #ifdef KSTACK_USAGE_PROF /* * Track maximum stack used by a thread in kernel. */ static int max_kstack_used; SYSCTL_INT(_debug, OID_AUTO, max_kstack_used, CTLFLAG_RD, &max_kstack_used, 0, "Maxiumum stack depth used by a thread in kernel"); void intr_prof_stack_use(struct thread *td, struct trapframe *frame) { vm_offset_t stack_top; vm_offset_t current; int used, prev_used; /* * Testing for interrupted kernel mode isn't strictly * needed. It optimizes the execution, since interrupts from * usermode will have only the trap frame on the stack. */ if (TRAPF_USERMODE(frame)) return; stack_top = td->td_kstack + td->td_kstack_pages * PAGE_SIZE; current = (vm_offset_t)(uintptr_t)&stack_top; /* * Try to detect if interrupt is using kernel thread stack. * Hardware could use a dedicated stack for interrupt handling. */ if (stack_top <= current || current < td->td_kstack) return; used = stack_top - current; for (;;) { prev_used = max_kstack_used; if (prev_used >= used) break; if (atomic_cmpset_int(&max_kstack_used, prev_used, used)) break; } } #endif /* KSTACK_USAGE_PROF */ /* * Implement fork's actions on an address space. * Here we arrange for the address space to be copied or referenced, * allocate a user struct (pcb and kernel stack), then call the * machine-dependent layer to fill those in and make the new process * ready to run. The new process is set up so that it returns directly * to user mode to avoid stack copying and relocation problems. */ int vm_forkproc(struct thread *td, struct proc *p2, struct thread *td2, struct vmspace *vm2, int flags) { struct proc *p1 = td->td_proc; struct domainset *dset; int error; if ((flags & RFPROC) == 0) { /* * Divorce the memory, if it is shared, essentially * this changes shared memory amongst threads, into * COW locally. */ if ((flags & RFMEM) == 0) { if (p1->p_vmspace->vm_refcnt > 1) { error = vmspace_unshare(p1); if (error) return (error); } } cpu_fork(td, p2, td2, flags); return (0); } if (flags & RFMEM) { p2->p_vmspace = p1->p_vmspace; atomic_add_int(&p1->p_vmspace->vm_refcnt, 1); } dset = td2->td_domain.dr_policy; while (vm_page_count_severe_set(&dset->ds_mask)) { vm_wait_doms(&dset->ds_mask); } if ((flags & RFMEM) == 0) { p2->p_vmspace = vm2; if (p1->p_vmspace->vm_shm) shmfork(p1, p2); } /* * cpu_fork will copy and update the pcb, set up the kernel stack, * and make the child ready to run. */ cpu_fork(td, p2, td2, flags); return (0); } /* * Called after process has been wait(2)'ed upon and is being reaped. * The idea is to reclaim resources that we could not reclaim while * the process was still executing. */ void vm_waitproc(p) struct proc *p; { vmspace_exitfree(p); /* and clean-out the vmspace */ } void kick_proc0(void) { wakeup(&proc0); } Index: head/sys/vm/vm_page.c =================================================================== --- head/sys/vm/vm_page.c (revision 355001) +++ head/sys/vm/vm_page.c (revision 355002) @@ -1,5098 +1,5096 @@ /*- * SPDX-License-Identifier: (BSD-3-Clause AND MIT-CMU) * * Copyright (c) 1991 Regents of the University of California. * All rights reserved. * Copyright (c) 1998 Matthew Dillon. All Rights Reserved. * * This code is derived from software contributed to Berkeley by * The Mach Operating System project at Carnegie-Mellon University. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91 */ /*- * Copyright (c) 1987, 1990 Carnegie-Mellon University. * All rights reserved. * * Authors: Avadis Tevanian, Jr., Michael Wayne Young * * Permission to use, copy, modify and distribute this software and * its documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. */ /* * Resident memory management module. */ #include __FBSDID("$FreeBSD$"); #include "opt_vm.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern int uma_startup_count(int); extern void uma_startup(void *, int); extern int vmem_startup_count(void); struct vm_domain vm_dom[MAXMEMDOM]; DPCPU_DEFINE_STATIC(struct vm_batchqueue, pqbatch[MAXMEMDOM][PQ_COUNT]); struct mtx_padalign __exclusive_cache_line pa_lock[PA_LOCK_COUNT]; struct mtx_padalign __exclusive_cache_line vm_domainset_lock; /* The following fields are protected by the domainset lock. */ domainset_t __exclusive_cache_line vm_min_domains; domainset_t __exclusive_cache_line vm_severe_domains; static int vm_min_waiters; static int vm_severe_waiters; static int vm_pageproc_waiters; static SYSCTL_NODE(_vm_stats, OID_AUTO, page, CTLFLAG_RD, 0, "VM page statistics"); static counter_u64_t queue_ops = EARLY_COUNTER; SYSCTL_COUNTER_U64(_vm_stats_page, OID_AUTO, queue_ops, CTLFLAG_RD, &queue_ops, "Number of batched queue operations"); static counter_u64_t queue_nops = EARLY_COUNTER; SYSCTL_COUNTER_U64(_vm_stats_page, OID_AUTO, queue_nops, CTLFLAG_RD, &queue_nops, "Number of batched queue operations with no effects"); static void counter_startup(void) { queue_ops = counter_u64_alloc(M_WAITOK); queue_nops = counter_u64_alloc(M_WAITOK); } SYSINIT(page_counters, SI_SUB_CPU, SI_ORDER_ANY, counter_startup, NULL); /* * bogus page -- for I/O to/from partially complete buffers, * or for paging into sparsely invalid regions. */ vm_page_t bogus_page; vm_page_t vm_page_array; long vm_page_array_size; long first_page; static int boot_pages; SYSCTL_INT(_vm, OID_AUTO, boot_pages, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &boot_pages, 0, "number of pages allocated for bootstrapping the VM system"); static TAILQ_HEAD(, vm_page) blacklist_head; static int sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS); SYSCTL_PROC(_vm, OID_AUTO, page_blacklist, CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_page_blacklist, "A", "Blacklist pages"); static uma_zone_t fakepg_zone; static void vm_page_alloc_check(vm_page_t m); static void _vm_page_busy_sleep(vm_object_t obj, vm_page_t m, const char *wmesg, bool nonshared, bool locked); static void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits); static void vm_page_dequeue_complete(vm_page_t m); static void vm_page_enqueue(vm_page_t m, uint8_t queue); static void vm_page_init(void *dummy); static int vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex, vm_page_t mpred); static void vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred); static void vm_page_mvqueue(vm_page_t m, uint8_t queue); static int vm_page_reclaim_run(int req_class, int domain, u_long npages, vm_page_t m_run, vm_paddr_t high); static int vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object, int req); static int vm_page_zone_import(void *arg, void **store, int cnt, int domain, int flags); static void vm_page_zone_release(void *arg, void **store, int cnt); SYSINIT(vm_page, SI_SUB_VM, SI_ORDER_SECOND, vm_page_init, NULL); static void vm_page_init(void *dummy) { fakepg_zone = uma_zcreate("fakepg", sizeof(struct vm_page), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE | UMA_ZONE_VM); bogus_page = vm_page_alloc(NULL, 0, VM_ALLOC_NOOBJ | VM_ALLOC_NORMAL | VM_ALLOC_WIRED); } /* * The cache page zone is initialized later since we need to be able to allocate * pages before UMA is fully initialized. */ static void vm_page_init_cache_zones(void *dummy __unused) { struct vm_domain *vmd; struct vm_pgcache *pgcache; - int domain, maxcache, pool; + int cache, domain, maxcache, pool; maxcache = 0; TUNABLE_INT_FETCH("vm.pgcache_zone_max", &maxcache); for (domain = 0; domain < vm_ndomains; domain++) { vmd = VM_DOMAIN(domain); - - /* - * Don't allow the page caches to take up more than .1875% of - * memory. A UMA bucket contains at most 256 free pages, and we - * have two buckets per CPU per free pool. - */ - if (vmd->vmd_page_count / 600 < 2 * 256 * mp_ncpus * - VM_NFREEPOOL) - continue; for (pool = 0; pool < VM_NFREEPOOL; pool++) { pgcache = &vmd->vmd_pgcache[pool]; pgcache->domain = domain; pgcache->pool = pool; pgcache->zone = uma_zcache_create("vm pgcache", - sizeof(struct vm_page), NULL, NULL, NULL, NULL, + PAGE_SIZE, NULL, NULL, NULL, NULL, vm_page_zone_import, vm_page_zone_release, pgcache, - UMA_ZONE_MAXBUCKET | UMA_ZONE_VM); - (void)uma_zone_set_maxcache(pgcache->zone, maxcache); + UMA_ZONE_VM); + + /* + * Limit each pool's zone to 0.1% of the pages in the + * domain. + */ + cache = maxcache != 0 ? maxcache : + vmd->vmd_page_count / 1000; + uma_zone_set_maxcache(pgcache->zone, cache); } } } SYSINIT(vm_page2, SI_SUB_VM_CONF, SI_ORDER_ANY, vm_page_init_cache_zones, NULL); /* Make sure that u_long is at least 64 bits when PAGE_SIZE is 32K. */ #if PAGE_SIZE == 32768 #ifdef CTASSERT CTASSERT(sizeof(u_long) >= 8); #endif #endif /* * vm_set_page_size: * * Sets the page size, perhaps based upon the memory * size. Must be called before any use of page-size * dependent functions. */ void vm_set_page_size(void) { if (vm_cnt.v_page_size == 0) vm_cnt.v_page_size = PAGE_SIZE; if (((vm_cnt.v_page_size - 1) & vm_cnt.v_page_size) != 0) panic("vm_set_page_size: page size not a power of two"); } /* * vm_page_blacklist_next: * * Find the next entry in the provided string of blacklist * addresses. Entries are separated by space, comma, or newline. * If an invalid integer is encountered then the rest of the * string is skipped. Updates the list pointer to the next * character, or NULL if the string is exhausted or invalid. */ static vm_paddr_t vm_page_blacklist_next(char **list, char *end) { vm_paddr_t bad; char *cp, *pos; if (list == NULL || *list == NULL) return (0); if (**list =='\0') { *list = NULL; return (0); } /* * If there's no end pointer then the buffer is coming from * the kenv and we know it's null-terminated. */ if (end == NULL) end = *list + strlen(*list); /* Ensure that strtoq() won't walk off the end */ if (*end != '\0') { if (*end == '\n' || *end == ' ' || *end == ',') *end = '\0'; else { printf("Blacklist not terminated, skipping\n"); *list = NULL; return (0); } } for (pos = *list; *pos != '\0'; pos = cp) { bad = strtoq(pos, &cp, 0); if (*cp == '\0' || *cp == ' ' || *cp == ',' || *cp == '\n') { if (bad == 0) { if (++cp < end) continue; else break; } } else break; if (*cp == '\0' || ++cp >= end) *list = NULL; else *list = cp; return (trunc_page(bad)); } printf("Garbage in RAM blacklist, skipping\n"); *list = NULL; return (0); } bool vm_page_blacklist_add(vm_paddr_t pa, bool verbose) { struct vm_domain *vmd; vm_page_t m; int ret; m = vm_phys_paddr_to_vm_page(pa); if (m == NULL) return (true); /* page does not exist, no failure */ vmd = vm_pagequeue_domain(m); vm_domain_free_lock(vmd); ret = vm_phys_unfree_page(m); vm_domain_free_unlock(vmd); if (ret != 0) { vm_domain_freecnt_inc(vmd, -1); TAILQ_INSERT_TAIL(&blacklist_head, m, listq); if (verbose) printf("Skipping page with pa 0x%jx\n", (uintmax_t)pa); } return (ret); } /* * vm_page_blacklist_check: * * Iterate through the provided string of blacklist addresses, pulling * each entry out of the physical allocator free list and putting it * onto a list for reporting via the vm.page_blacklist sysctl. */ static void vm_page_blacklist_check(char *list, char *end) { vm_paddr_t pa; char *next; next = list; while (next != NULL) { if ((pa = vm_page_blacklist_next(&next, end)) == 0) continue; vm_page_blacklist_add(pa, bootverbose); } } /* * vm_page_blacklist_load: * * Search for a special module named "ram_blacklist". It'll be a * plain text file provided by the user via the loader directive * of the same name. */ static void vm_page_blacklist_load(char **list, char **end) { void *mod; u_char *ptr; u_int len; mod = NULL; ptr = NULL; mod = preload_search_by_type("ram_blacklist"); if (mod != NULL) { ptr = preload_fetch_addr(mod); len = preload_fetch_size(mod); } *list = ptr; if (ptr != NULL) *end = ptr + len; else *end = NULL; return; } static int sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS) { vm_page_t m; struct sbuf sbuf; int error, first; first = 1; error = sysctl_wire_old_buffer(req, 0); if (error != 0) return (error); sbuf_new_for_sysctl(&sbuf, NULL, 128, req); TAILQ_FOREACH(m, &blacklist_head, listq) { sbuf_printf(&sbuf, "%s%#jx", first ? "" : ",", (uintmax_t)m->phys_addr); first = 0; } error = sbuf_finish(&sbuf); sbuf_delete(&sbuf); return (error); } /* * Initialize a dummy page for use in scans of the specified paging queue. * In principle, this function only needs to set the flag PG_MARKER. * Nonetheless, it write busies the page as a safety precaution. */ static void vm_page_init_marker(vm_page_t marker, int queue, uint16_t aflags) { bzero(marker, sizeof(*marker)); marker->flags = PG_MARKER; marker->aflags = aflags; marker->busy_lock = VPB_SINGLE_EXCLUSIVER; marker->queue = queue; } static void vm_page_domain_init(int domain) { struct vm_domain *vmd; struct vm_pagequeue *pq; int i; vmd = VM_DOMAIN(domain); bzero(vmd, sizeof(*vmd)); *__DECONST(char **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_name) = "vm inactive pagequeue"; *__DECONST(char **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_name) = "vm active pagequeue"; *__DECONST(char **, &vmd->vmd_pagequeues[PQ_LAUNDRY].pq_name) = "vm laundry pagequeue"; *__DECONST(char **, &vmd->vmd_pagequeues[PQ_UNSWAPPABLE].pq_name) = "vm unswappable pagequeue"; vmd->vmd_domain = domain; vmd->vmd_page_count = 0; vmd->vmd_free_count = 0; vmd->vmd_segs = 0; vmd->vmd_oom = FALSE; for (i = 0; i < PQ_COUNT; i++) { pq = &vmd->vmd_pagequeues[i]; TAILQ_INIT(&pq->pq_pl); mtx_init(&pq->pq_mutex, pq->pq_name, "vm pagequeue", MTX_DEF | MTX_DUPOK); pq->pq_pdpages = 0; vm_page_init_marker(&vmd->vmd_markers[i], i, 0); } mtx_init(&vmd->vmd_free_mtx, "vm page free queue", NULL, MTX_DEF); mtx_init(&vmd->vmd_pageout_mtx, "vm pageout lock", NULL, MTX_DEF); snprintf(vmd->vmd_name, sizeof(vmd->vmd_name), "%d", domain); /* * inacthead is used to provide FIFO ordering for LRU-bypassing * insertions. */ vm_page_init_marker(&vmd->vmd_inacthead, PQ_INACTIVE, PGA_ENQUEUED); TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_INACTIVE].pq_pl, &vmd->vmd_inacthead, plinks.q); /* * The clock pages are used to implement active queue scanning without * requeues. Scans start at clock[0], which is advanced after the scan * ends. When the two clock hands meet, they are reset and scanning * resumes from the head of the queue. */ vm_page_init_marker(&vmd->vmd_clock[0], PQ_ACTIVE, PGA_ENQUEUED); vm_page_init_marker(&vmd->vmd_clock[1], PQ_ACTIVE, PGA_ENQUEUED); TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl, &vmd->vmd_clock[0], plinks.q); TAILQ_INSERT_TAIL(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl, &vmd->vmd_clock[1], plinks.q); } /* * Initialize a physical page in preparation for adding it to the free * lists. */ static void vm_page_init_page(vm_page_t m, vm_paddr_t pa, int segind) { m->object = NULL; m->ref_count = 0; m->busy_lock = VPB_UNBUSIED; m->flags = m->aflags = 0; m->phys_addr = pa; m->queue = PQ_NONE; m->psind = 0; m->segind = segind; m->order = VM_NFREEORDER; m->pool = VM_FREEPOOL_DEFAULT; m->valid = m->dirty = 0; pmap_page_init(m); } #ifndef PMAP_HAS_PAGE_ARRAY static vm_paddr_t vm_page_array_alloc(vm_offset_t *vaddr, vm_paddr_t end, vm_paddr_t page_range) { vm_paddr_t new_end; /* * Reserve an unmapped guard page to trap access to vm_page_array[-1]. * However, because this page is allocated from KVM, out-of-bounds * accesses using the direct map will not be trapped. */ *vaddr += PAGE_SIZE; /* * Allocate physical memory for the page structures, and map it. */ new_end = trunc_page(end - page_range * sizeof(struct vm_page)); vm_page_array = (vm_page_t)pmap_map(vaddr, new_end, end, VM_PROT_READ | VM_PROT_WRITE); vm_page_array_size = page_range; return (new_end); } #endif /* * vm_page_startup: * * Initializes the resident memory module. Allocates physical memory for * bootstrapping UMA and some data structures that are used to manage * physical pages. Initializes these structures, and populates the free * page queues. */ vm_offset_t vm_page_startup(vm_offset_t vaddr) { struct vm_phys_seg *seg; vm_page_t m; char *list, *listend; vm_offset_t mapped; vm_paddr_t end, high_avail, low_avail, new_end, page_range, size; vm_paddr_t last_pa, pa; u_long pagecount; int biggestone, i, segind; #ifdef WITNESS int witness_size; #endif #if defined(__i386__) && defined(VM_PHYSSEG_DENSE) long ii; #endif vaddr = round_page(vaddr); vm_phys_early_startup(); biggestone = vm_phys_avail_largest(); end = phys_avail[biggestone+1]; /* * Initialize the page and queue locks. */ mtx_init(&vm_domainset_lock, "vm domainset lock", NULL, MTX_DEF); for (i = 0; i < PA_LOCK_COUNT; i++) mtx_init(&pa_lock[i], "vm page", NULL, MTX_DEF); for (i = 0; i < vm_ndomains; i++) vm_page_domain_init(i); /* * Allocate memory for use when boot strapping the kernel memory * allocator. Tell UMA how many zones we are going to create * before going fully functional. UMA will add its zones. * * VM startup zones: vmem, vmem_btag, VM OBJECT, RADIX NODE, MAP, * KMAP ENTRY, MAP ENTRY, VMSPACE. */ boot_pages = uma_startup_count(8); #ifndef UMA_MD_SMALL_ALLOC /* vmem_startup() calls uma_prealloc(). */ boot_pages += vmem_startup_count(); /* vm_map_startup() calls uma_prealloc(). */ boot_pages += howmany(MAX_KMAP, UMA_SLAB_SPACE / sizeof(struct vm_map)); /* * Before going fully functional kmem_init() does allocation * from "KMAP ENTRY" and vmem_create() does allocation from "vmem". */ boot_pages += 2; #endif /* * CTFLAG_RDTUN doesn't work during the early boot process, so we must * manually fetch the value. */ TUNABLE_INT_FETCH("vm.boot_pages", &boot_pages); new_end = end - (boot_pages * UMA_SLAB_SIZE); new_end = trunc_page(new_end); mapped = pmap_map(&vaddr, new_end, end, VM_PROT_READ | VM_PROT_WRITE); bzero((void *)mapped, end - new_end); uma_startup((void *)mapped, boot_pages); #ifdef WITNESS witness_size = round_page(witness_startup_count()); new_end -= witness_size; mapped = pmap_map(&vaddr, new_end, new_end + witness_size, VM_PROT_READ | VM_PROT_WRITE); bzero((void *)mapped, witness_size); witness_startup((void *)mapped); #endif #if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \ defined(__i386__) || defined(__mips__) || defined(__riscv) || \ defined(__powerpc64__) /* * Allocate a bitmap to indicate that a random physical page * needs to be included in a minidump. * * The amd64 port needs this to indicate which direct map pages * need to be dumped, via calls to dump_add_page()/dump_drop_page(). * * However, i386 still needs this workspace internally within the * minidump code. In theory, they are not needed on i386, but are * included should the sf_buf code decide to use them. */ last_pa = 0; for (i = 0; dump_avail[i + 1] != 0; i += 2) if (dump_avail[i + 1] > last_pa) last_pa = dump_avail[i + 1]; page_range = last_pa / PAGE_SIZE; vm_page_dump_size = round_page(roundup2(page_range, NBBY) / NBBY); new_end -= vm_page_dump_size; vm_page_dump = (void *)(uintptr_t)pmap_map(&vaddr, new_end, new_end + vm_page_dump_size, VM_PROT_READ | VM_PROT_WRITE); bzero((void *)vm_page_dump, vm_page_dump_size); #else (void)last_pa; #endif #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \ defined(__riscv) || defined(__powerpc64__) /* * Include the UMA bootstrap pages, witness pages and vm_page_dump * in a crash dump. When pmap_map() uses the direct map, they are * not automatically included. */ for (pa = new_end; pa < end; pa += PAGE_SIZE) dump_add_page(pa); #endif phys_avail[biggestone + 1] = new_end; #ifdef __amd64__ /* * Request that the physical pages underlying the message buffer be * included in a crash dump. Since the message buffer is accessed * through the direct map, they are not automatically included. */ pa = DMAP_TO_PHYS((vm_offset_t)msgbufp->msg_ptr); last_pa = pa + round_page(msgbufsize); while (pa < last_pa) { dump_add_page(pa); pa += PAGE_SIZE; } #endif /* * Compute the number of pages of memory that will be available for * use, taking into account the overhead of a page structure per page. * In other words, solve * "available physical memory" - round_page(page_range * * sizeof(struct vm_page)) = page_range * PAGE_SIZE * for page_range. */ low_avail = phys_avail[0]; high_avail = phys_avail[1]; for (i = 0; i < vm_phys_nsegs; i++) { if (vm_phys_segs[i].start < low_avail) low_avail = vm_phys_segs[i].start; if (vm_phys_segs[i].end > high_avail) high_avail = vm_phys_segs[i].end; } /* Skip the first chunk. It is already accounted for. */ for (i = 2; phys_avail[i + 1] != 0; i += 2) { if (phys_avail[i] < low_avail) low_avail = phys_avail[i]; if (phys_avail[i + 1] > high_avail) high_avail = phys_avail[i + 1]; } first_page = low_avail / PAGE_SIZE; #ifdef VM_PHYSSEG_SPARSE size = 0; for (i = 0; i < vm_phys_nsegs; i++) size += vm_phys_segs[i].end - vm_phys_segs[i].start; for (i = 0; phys_avail[i + 1] != 0; i += 2) size += phys_avail[i + 1] - phys_avail[i]; #elif defined(VM_PHYSSEG_DENSE) size = high_avail - low_avail; #else #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." #endif #ifdef PMAP_HAS_PAGE_ARRAY pmap_page_array_startup(size / PAGE_SIZE); biggestone = vm_phys_avail_largest(); end = new_end = phys_avail[biggestone + 1]; #else #ifdef VM_PHYSSEG_DENSE /* * In the VM_PHYSSEG_DENSE case, the number of pages can account for * the overhead of a page structure per page only if vm_page_array is * allocated from the last physical memory chunk. Otherwise, we must * allocate page structures representing the physical memory * underlying vm_page_array, even though they will not be used. */ if (new_end != high_avail) page_range = size / PAGE_SIZE; else #endif { page_range = size / (PAGE_SIZE + sizeof(struct vm_page)); /* * If the partial bytes remaining are large enough for * a page (PAGE_SIZE) without a corresponding * 'struct vm_page', then new_end will contain an * extra page after subtracting the length of the VM * page array. Compensate by subtracting an extra * page from new_end. */ if (size % (PAGE_SIZE + sizeof(struct vm_page)) >= PAGE_SIZE) { if (new_end == high_avail) high_avail -= PAGE_SIZE; new_end -= PAGE_SIZE; } } end = new_end; new_end = vm_page_array_alloc(&vaddr, end, page_range); #endif #if VM_NRESERVLEVEL > 0 /* * Allocate physical memory for the reservation management system's * data structures, and map it. */ new_end = vm_reserv_startup(&vaddr, new_end); #endif #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \ defined(__riscv) || defined(__powerpc64__) /* * Include vm_page_array and vm_reserv_array in a crash dump. */ for (pa = new_end; pa < end; pa += PAGE_SIZE) dump_add_page(pa); #endif phys_avail[biggestone + 1] = new_end; /* * Add physical memory segments corresponding to the available * physical pages. */ for (i = 0; phys_avail[i + 1] != 0; i += 2) if (vm_phys_avail_size(i) != 0) vm_phys_add_seg(phys_avail[i], phys_avail[i + 1]); /* * Initialize the physical memory allocator. */ vm_phys_init(); /* * Initialize the page structures and add every available page to the * physical memory allocator's free lists. */ #if defined(__i386__) && defined(VM_PHYSSEG_DENSE) for (ii = 0; ii < vm_page_array_size; ii++) { m = &vm_page_array[ii]; vm_page_init_page(m, (first_page + ii) << PAGE_SHIFT, 0); m->flags = PG_FICTITIOUS; } #endif vm_cnt.v_page_count = 0; for (segind = 0; segind < vm_phys_nsegs; segind++) { seg = &vm_phys_segs[segind]; for (m = seg->first_page, pa = seg->start; pa < seg->end; m++, pa += PAGE_SIZE) vm_page_init_page(m, pa, segind); /* * Add the segment to the free lists only if it is covered by * one of the ranges in phys_avail. Because we've added the * ranges to the vm_phys_segs array, we can assume that each * segment is either entirely contained in one of the ranges, * or doesn't overlap any of them. */ for (i = 0; phys_avail[i + 1] != 0; i += 2) { struct vm_domain *vmd; if (seg->start < phys_avail[i] || seg->end > phys_avail[i + 1]) continue; m = seg->first_page; pagecount = (u_long)atop(seg->end - seg->start); vmd = VM_DOMAIN(seg->domain); vm_domain_free_lock(vmd); vm_phys_enqueue_contig(m, pagecount); vm_domain_free_unlock(vmd); vm_domain_freecnt_inc(vmd, pagecount); vm_cnt.v_page_count += (u_int)pagecount; vmd = VM_DOMAIN(seg->domain); vmd->vmd_page_count += (u_int)pagecount; vmd->vmd_segs |= 1UL << m->segind; break; } } /* * Remove blacklisted pages from the physical memory allocator. */ TAILQ_INIT(&blacklist_head); vm_page_blacklist_load(&list, &listend); vm_page_blacklist_check(list, listend); list = kern_getenv("vm.blacklist"); vm_page_blacklist_check(list, NULL); freeenv(list); #if VM_NRESERVLEVEL > 0 /* * Initialize the reservation management system. */ vm_reserv_init(); #endif return (vaddr); } void vm_page_reference(vm_page_t m) { vm_page_aflag_set(m, PGA_REFERENCED); } /* * vm_page_busy_acquire: * * Acquire the busy lock as described by VM_ALLOC_* flags. Will loop * and drop the object lock if necessary. */ int vm_page_busy_acquire(vm_page_t m, int allocflags) { vm_object_t obj; bool locked; /* * The page-specific object must be cached because page * identity can change during the sleep, causing the * re-lock of a different object. * It is assumed that a reference to the object is already * held by the callers. */ obj = m->object; for (;;) { if ((allocflags & VM_ALLOC_SBUSY) == 0) { if (vm_page_tryxbusy(m)) return (TRUE); } else { if (vm_page_trysbusy(m)) return (TRUE); } if ((allocflags & VM_ALLOC_NOWAIT) != 0) return (FALSE); if (obj != NULL) locked = VM_OBJECT_WOWNED(obj); else locked = FALSE; MPASS(locked || vm_page_wired(m)); _vm_page_busy_sleep(obj, m, "vmpba", (allocflags & VM_ALLOC_SBUSY) != 0, locked); if (locked) VM_OBJECT_WLOCK(obj); if ((allocflags & VM_ALLOC_WAITFAIL) != 0) return (FALSE); KASSERT(m->object == obj || m->object == NULL, ("vm_page_busy_acquire: page %p does not belong to %p", m, obj)); } } /* * vm_page_busy_downgrade: * * Downgrade an exclusive busy page into a single shared busy page. */ void vm_page_busy_downgrade(vm_page_t m) { u_int x; vm_page_assert_xbusied(m); x = m->busy_lock; for (;;) { if (atomic_fcmpset_rel_int(&m->busy_lock, &x, VPB_SHARERS_WORD(1))) break; } if ((x & VPB_BIT_WAITERS) != 0) wakeup(m); } /* * * vm_page_busy_tryupgrade: * * Attempt to upgrade a single shared busy into an exclusive busy. */ int vm_page_busy_tryupgrade(vm_page_t m) { u_int x; vm_page_assert_sbusied(m); x = m->busy_lock; for (;;) { if (VPB_SHARERS(x) > 1) return (0); KASSERT((x & ~VPB_BIT_WAITERS) == VPB_SHARERS_WORD(1), ("vm_page_busy_tryupgrade: invalid lock state")); if (!atomic_fcmpset_acq_int(&m->busy_lock, &x, VPB_SINGLE_EXCLUSIVER | (x & VPB_BIT_WAITERS))) continue; return (1); } } /* * vm_page_sbusied: * * Return a positive value if the page is shared busied, 0 otherwise. */ int vm_page_sbusied(vm_page_t m) { u_int x; x = m->busy_lock; return ((x & VPB_BIT_SHARED) != 0 && x != VPB_UNBUSIED); } /* * vm_page_sunbusy: * * Shared unbusy a page. */ void vm_page_sunbusy(vm_page_t m) { u_int x; vm_page_assert_sbusied(m); x = m->busy_lock; for (;;) { if (VPB_SHARERS(x) > 1) { if (atomic_fcmpset_int(&m->busy_lock, &x, x - VPB_ONE_SHARER)) break; continue; } KASSERT((x & ~VPB_BIT_WAITERS) == VPB_SHARERS_WORD(1), ("vm_page_sunbusy: invalid lock state")); if (!atomic_fcmpset_rel_int(&m->busy_lock, &x, VPB_UNBUSIED)) continue; if ((x & VPB_BIT_WAITERS) == 0) break; wakeup(m); break; } } /* * vm_page_busy_sleep: * * Sleep if the page is busy, using the page pointer as wchan. * This is used to implement the hard-path of busying mechanism. * * If nonshared is true, sleep only if the page is xbusy. * * The object lock must be held on entry and will be released on exit. */ void vm_page_busy_sleep(vm_page_t m, const char *wmesg, bool nonshared) { vm_object_t obj; obj = m->object; VM_OBJECT_ASSERT_LOCKED(obj); vm_page_lock_assert(m, MA_NOTOWNED); _vm_page_busy_sleep(obj, m, wmesg, nonshared, true); } static void _vm_page_busy_sleep(vm_object_t obj, vm_page_t m, const char *wmesg, bool nonshared, bool locked) { u_int x; /* * If the object is busy we must wait for that to drain to zero * before trying the page again. */ if (obj != NULL && vm_object_busied(obj)) { if (locked) VM_OBJECT_DROP(obj); vm_object_busy_wait(obj, wmesg); return; } sleepq_lock(m); x = m->busy_lock; if (x == VPB_UNBUSIED || (nonshared && (x & VPB_BIT_SHARED) != 0) || ((x & VPB_BIT_WAITERS) == 0 && !atomic_cmpset_int(&m->busy_lock, x, x | VPB_BIT_WAITERS))) { if (locked) VM_OBJECT_DROP(obj); sleepq_release(m); return; } if (locked) VM_OBJECT_DROP(obj); DROP_GIANT(); sleepq_add(m, NULL, wmesg, 0, 0); sleepq_wait(m, PVM); PICKUP_GIANT(); } /* * vm_page_trysbusy: * * Try to shared busy a page. * If the operation succeeds 1 is returned otherwise 0. * The operation never sleeps. */ int vm_page_trysbusy(vm_page_t m) { vm_object_t obj; u_int x; obj = m->object; x = m->busy_lock; for (;;) { if ((x & VPB_BIT_SHARED) == 0) return (0); /* * Reduce the window for transient busies that will trigger * false negatives in vm_page_ps_test(). */ if (obj != NULL && vm_object_busied(obj)) return (0); if (atomic_fcmpset_acq_int(&m->busy_lock, &x, x + VPB_ONE_SHARER)) break; } /* Refetch the object now that we're guaranteed that it is stable. */ obj = m->object; if (obj != NULL && vm_object_busied(obj)) { vm_page_sunbusy(m); return (0); } return (1); } /* * vm_page_tryxbusy: * * Try to exclusive busy a page. * If the operation succeeds 1 is returned otherwise 0. * The operation never sleeps. */ int vm_page_tryxbusy(vm_page_t m) { vm_object_t obj; if (atomic_cmpset_acq_int(&(m)->busy_lock, VPB_UNBUSIED, VPB_SINGLE_EXCLUSIVER) == 0) return (0); obj = m->object; if (obj != NULL && vm_object_busied(obj)) { vm_page_xunbusy(m); return (0); } return (1); } /* * vm_page_xunbusy_hard: * * Called when unbusy has failed because there is a waiter. */ void vm_page_xunbusy_hard(vm_page_t m) { vm_page_assert_xbusied(m); /* * Wake the waiter. */ atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED); wakeup(m); } /* * Avoid releasing and reacquiring the same page lock. */ void vm_page_change_lock(vm_page_t m, struct mtx **mtx) { struct mtx *mtx1; mtx1 = vm_page_lockptr(m); if (*mtx == mtx1) return; if (*mtx != NULL) mtx_unlock(*mtx); *mtx = mtx1; mtx_lock(mtx1); } /* * vm_page_unhold_pages: * * Unhold each of the pages that is referenced by the given array. */ void vm_page_unhold_pages(vm_page_t *ma, int count) { for (; count != 0; count--) { vm_page_unwire(*ma, PQ_ACTIVE); ma++; } } vm_page_t PHYS_TO_VM_PAGE(vm_paddr_t pa) { vm_page_t m; #ifdef VM_PHYSSEG_SPARSE m = vm_phys_paddr_to_vm_page(pa); if (m == NULL) m = vm_phys_fictitious_to_vm_page(pa); return (m); #elif defined(VM_PHYSSEG_DENSE) long pi; pi = atop(pa); if (pi >= first_page && (pi - first_page) < vm_page_array_size) { m = &vm_page_array[pi - first_page]; return (m); } return (vm_phys_fictitious_to_vm_page(pa)); #else #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." #endif } /* * vm_page_getfake: * * Create a fictitious page with the specified physical address and * memory attribute. The memory attribute is the only the machine- * dependent aspect of a fictitious page that must be initialized. */ vm_page_t vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr) { vm_page_t m; m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO); vm_page_initfake(m, paddr, memattr); return (m); } void vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) { if ((m->flags & PG_FICTITIOUS) != 0) { /* * The page's memattr might have changed since the * previous initialization. Update the pmap to the * new memattr. */ goto memattr; } m->phys_addr = paddr; m->queue = PQ_NONE; /* Fictitious pages don't use "segind". */ m->flags = PG_FICTITIOUS; /* Fictitious pages don't use "order" or "pool". */ m->oflags = VPO_UNMANAGED; m->busy_lock = VPB_SINGLE_EXCLUSIVER; /* Fictitious pages are unevictable. */ m->ref_count = 1; pmap_page_init(m); memattr: pmap_page_set_memattr(m, memattr); } /* * vm_page_putfake: * * Release a fictitious page. */ void vm_page_putfake(vm_page_t m) { KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m)); KASSERT((m->flags & PG_FICTITIOUS) != 0, ("vm_page_putfake: bad page %p", m)); if (vm_page_xbusied(m)) vm_page_xunbusy(m); uma_zfree(fakepg_zone, m); } /* * vm_page_updatefake: * * Update the given fictitious page to the specified physical address and * memory attribute. */ void vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) { KASSERT((m->flags & PG_FICTITIOUS) != 0, ("vm_page_updatefake: bad page %p", m)); m->phys_addr = paddr; pmap_page_set_memattr(m, memattr); } /* * vm_page_free: * * Free a page. */ void vm_page_free(vm_page_t m) { m->flags &= ~PG_ZERO; vm_page_free_toq(m); } /* * vm_page_free_zero: * * Free a page to the zerod-pages queue */ void vm_page_free_zero(vm_page_t m) { m->flags |= PG_ZERO; vm_page_free_toq(m); } /* * Unbusy and handle the page queueing for a page from a getpages request that * was optionally read ahead or behind. */ void vm_page_readahead_finish(vm_page_t m) { /* We shouldn't put invalid pages on queues. */ KASSERT(!vm_page_none_valid(m), ("%s: %p is invalid", __func__, m)); /* * Since the page is not the actually needed one, whether it should * be activated or deactivated is not obvious. Empirical results * have shown that deactivating the page is usually the best choice, * unless the page is wanted by another thread. */ vm_page_lock(m); if ((m->busy_lock & VPB_BIT_WAITERS) != 0) vm_page_activate(m); else vm_page_deactivate(m); vm_page_unlock(m); vm_page_xunbusy(m); } /* * vm_page_sleep_if_busy: * * Sleep and release the object lock if the page is busied. * Returns TRUE if the thread slept. * * The given page must be unlocked and object containing it must * be locked. */ int vm_page_sleep_if_busy(vm_page_t m, const char *msg) { vm_object_t obj; vm_page_lock_assert(m, MA_NOTOWNED); VM_OBJECT_ASSERT_WLOCKED(m->object); /* * The page-specific object must be cached because page * identity can change during the sleep, causing the * re-lock of a different object. * It is assumed that a reference to the object is already * held by the callers. */ obj = m->object; if (vm_page_busied(m) || (obj != NULL && obj->busy)) { vm_page_busy_sleep(m, msg, false); VM_OBJECT_WLOCK(obj); return (TRUE); } return (FALSE); } /* * vm_page_sleep_if_xbusy: * * Sleep and release the object lock if the page is xbusied. * Returns TRUE if the thread slept. * * The given page must be unlocked and object containing it must * be locked. */ int vm_page_sleep_if_xbusy(vm_page_t m, const char *msg) { vm_object_t obj; vm_page_lock_assert(m, MA_NOTOWNED); VM_OBJECT_ASSERT_WLOCKED(m->object); /* * The page-specific object must be cached because page * identity can change during the sleep, causing the * re-lock of a different object. * It is assumed that a reference to the object is already * held by the callers. */ obj = m->object; if (vm_page_xbusied(m) || (obj != NULL && obj->busy)) { vm_page_busy_sleep(m, msg, true); VM_OBJECT_WLOCK(obj); return (TRUE); } return (FALSE); } /* * vm_page_dirty_KBI: [ internal use only ] * * Set all bits in the page's dirty field. * * The object containing the specified page must be locked if the * call is made from the machine-independent layer. * * See vm_page_clear_dirty_mask(). * * This function should only be called by vm_page_dirty(). */ void vm_page_dirty_KBI(vm_page_t m) { /* Refer to this operation by its public name. */ KASSERT(vm_page_all_valid(m), ("vm_page_dirty: page is invalid!")); m->dirty = VM_PAGE_BITS_ALL; } /* * vm_page_insert: [ internal use only ] * * Inserts the given mem entry into the object and object list. * * The object must be locked. */ int vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex) { vm_page_t mpred; VM_OBJECT_ASSERT_WLOCKED(object); mpred = vm_radix_lookup_le(&object->rtree, pindex); return (vm_page_insert_after(m, object, pindex, mpred)); } /* * vm_page_insert_after: * * Inserts the page "m" into the specified object at offset "pindex". * * The page "mpred" must immediately precede the offset "pindex" within * the specified object. * * The object must be locked. */ static int vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex, vm_page_t mpred) { vm_page_t msucc; VM_OBJECT_ASSERT_WLOCKED(object); KASSERT(m->object == NULL, ("vm_page_insert_after: page already inserted")); if (mpred != NULL) { KASSERT(mpred->object == object, ("vm_page_insert_after: object doesn't contain mpred")); KASSERT(mpred->pindex < pindex, ("vm_page_insert_after: mpred doesn't precede pindex")); msucc = TAILQ_NEXT(mpred, listq); } else msucc = TAILQ_FIRST(&object->memq); if (msucc != NULL) KASSERT(msucc->pindex > pindex, ("vm_page_insert_after: msucc doesn't succeed pindex")); /* * Record the object/offset pair in this page. */ m->object = object; m->pindex = pindex; m->ref_count |= VPRC_OBJREF; /* * Now link into the object's ordered list of backed pages. */ if (vm_radix_insert(&object->rtree, m)) { m->object = NULL; m->pindex = 0; m->ref_count &= ~VPRC_OBJREF; return (1); } vm_page_insert_radixdone(m, object, mpred); return (0); } /* * vm_page_insert_radixdone: * * Complete page "m" insertion into the specified object after the * radix trie hooking. * * The page "mpred" must precede the offset "m->pindex" within the * specified object. * * The object must be locked. */ static void vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred) { VM_OBJECT_ASSERT_WLOCKED(object); KASSERT(object != NULL && m->object == object, ("vm_page_insert_radixdone: page %p has inconsistent object", m)); KASSERT((m->ref_count & VPRC_OBJREF) != 0, ("vm_page_insert_radixdone: page %p is missing object ref", m)); if (mpred != NULL) { KASSERT(mpred->object == object, ("vm_page_insert_radixdone: object doesn't contain mpred")); KASSERT(mpred->pindex < m->pindex, ("vm_page_insert_radixdone: mpred doesn't precede pindex")); } if (mpred != NULL) TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq); else TAILQ_INSERT_HEAD(&object->memq, m, listq); /* * Show that the object has one more resident page. */ object->resident_page_count++; /* * Hold the vnode until the last page is released. */ if (object->resident_page_count == 1 && object->type == OBJT_VNODE) vhold(object->handle); /* * Since we are inserting a new and possibly dirty page, * update the object's generation count. */ if (pmap_page_is_write_mapped(m)) vm_object_set_writeable_dirty(object); } /* * Do the work to remove a page from its object. The caller is responsible for * updating the page's fields to reflect this removal. */ static void vm_page_object_remove(vm_page_t m) { vm_object_t object; vm_page_t mrem; object = m->object; VM_OBJECT_ASSERT_WLOCKED(object); KASSERT((m->ref_count & VPRC_OBJREF) != 0, ("page %p is missing its object ref", m)); mrem = vm_radix_remove(&object->rtree, m->pindex); KASSERT(mrem == m, ("removed page %p, expected page %p", mrem, m)); /* * Now remove from the object's list of backed pages. */ TAILQ_REMOVE(&object->memq, m, listq); /* * And show that the object has one fewer resident page. */ object->resident_page_count--; /* * The vnode may now be recycled. */ if (object->resident_page_count == 0 && object->type == OBJT_VNODE) vdrop(object->handle); } /* * vm_page_remove: * * Removes the specified page from its containing object, but does not * invalidate any backing storage. Returns true if the object's reference * was the last reference to the page, and false otherwise. * * The object must be locked. */ bool vm_page_remove(vm_page_t m) { vm_page_object_remove(m); m->object = NULL; return (vm_page_drop(m, VPRC_OBJREF) == VPRC_OBJREF); } /* * vm_page_lookup: * * Returns the page associated with the object/offset * pair specified; if none is found, NULL is returned. * * The object must be locked. */ vm_page_t vm_page_lookup(vm_object_t object, vm_pindex_t pindex) { VM_OBJECT_ASSERT_LOCKED(object); return (vm_radix_lookup(&object->rtree, pindex)); } /* * vm_page_find_least: * * Returns the page associated with the object with least pindex * greater than or equal to the parameter pindex, or NULL. * * The object must be locked. */ vm_page_t vm_page_find_least(vm_object_t object, vm_pindex_t pindex) { vm_page_t m; VM_OBJECT_ASSERT_LOCKED(object); if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex) m = vm_radix_lookup_ge(&object->rtree, pindex); return (m); } /* * Returns the given page's successor (by pindex) within the object if it is * resident; if none is found, NULL is returned. * * The object must be locked. */ vm_page_t vm_page_next(vm_page_t m) { vm_page_t next; VM_OBJECT_ASSERT_LOCKED(m->object); if ((next = TAILQ_NEXT(m, listq)) != NULL) { MPASS(next->object == m->object); if (next->pindex != m->pindex + 1) next = NULL; } return (next); } /* * Returns the given page's predecessor (by pindex) within the object if it is * resident; if none is found, NULL is returned. * * The object must be locked. */ vm_page_t vm_page_prev(vm_page_t m) { vm_page_t prev; VM_OBJECT_ASSERT_LOCKED(m->object); if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL) { MPASS(prev->object == m->object); if (prev->pindex != m->pindex - 1) prev = NULL; } return (prev); } /* * Uses the page mnew as a replacement for an existing page at index * pindex which must be already present in the object. */ vm_page_t vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex) { vm_page_t mold; VM_OBJECT_ASSERT_WLOCKED(object); KASSERT(mnew->object == NULL && (mnew->ref_count & VPRC_OBJREF) == 0, ("vm_page_replace: page %p already in object", mnew)); /* * This function mostly follows vm_page_insert() and * vm_page_remove() without the radix, object count and vnode * dance. Double check such functions for more comments. */ mnew->object = object; mnew->pindex = pindex; atomic_set_int(&mnew->ref_count, VPRC_OBJREF); mold = vm_radix_replace(&object->rtree, mnew); KASSERT(mold->queue == PQ_NONE, ("vm_page_replace: old page %p is on a paging queue", mold)); /* Keep the resident page list in sorted order. */ TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq); TAILQ_REMOVE(&object->memq, mold, listq); mold->object = NULL; atomic_clear_int(&mold->ref_count, VPRC_OBJREF); vm_page_xunbusy(mold); /* * The object's resident_page_count does not change because we have * swapped one page for another, but the generation count should * change if the page is dirty. */ if (pmap_page_is_write_mapped(mnew)) vm_object_set_writeable_dirty(object); return (mold); } /* * vm_page_rename: * * Move the given memory entry from its * current object to the specified target object/offset. * * Note: swap associated with the page must be invalidated by the move. We * have to do this for several reasons: (1) we aren't freeing the * page, (2) we are dirtying the page, (3) the VM system is probably * moving the page from object A to B, and will then later move * the backing store from A to B and we can't have a conflict. * * Note: we *always* dirty the page. It is necessary both for the * fact that we moved it, and because we may be invalidating * swap. * * The objects must be locked. */ int vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex) { vm_page_t mpred; vm_pindex_t opidx; VM_OBJECT_ASSERT_WLOCKED(new_object); KASSERT(m->ref_count != 0, ("vm_page_rename: page %p has no refs", m)); mpred = vm_radix_lookup_le(&new_object->rtree, new_pindex); KASSERT(mpred == NULL || mpred->pindex != new_pindex, ("vm_page_rename: pindex already renamed")); /* * Create a custom version of vm_page_insert() which does not depend * by m_prev and can cheat on the implementation aspects of the * function. */ opidx = m->pindex; m->pindex = new_pindex; if (vm_radix_insert(&new_object->rtree, m)) { m->pindex = opidx; return (1); } /* * The operation cannot fail anymore. The removal must happen before * the listq iterator is tainted. */ m->pindex = opidx; vm_page_object_remove(m); /* Return back to the new pindex to complete vm_page_insert(). */ m->pindex = new_pindex; m->object = new_object; vm_page_insert_radixdone(m, new_object, mpred); vm_page_dirty(m); return (0); } /* * vm_page_alloc: * * Allocate and return a page that is associated with the specified * object and offset pair. By default, this page is exclusive busied. * * The caller must always specify an allocation class. * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * * optional allocation flags: * VM_ALLOC_COUNT(number) the number of additional pages that the caller * intends to allocate * VM_ALLOC_NOBUSY do not exclusive busy the page * VM_ALLOC_NODUMP do not include the page in a kernel core dump * VM_ALLOC_NOOBJ page is not associated with an object and * should not be exclusive busy * VM_ALLOC_SBUSY shared busy the allocated page * VM_ALLOC_WIRED wire the allocated page * VM_ALLOC_ZERO prefer a zeroed page */ vm_page_t vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req) { return (vm_page_alloc_after(object, pindex, req, object != NULL ? vm_radix_lookup_le(&object->rtree, pindex) : NULL)); } vm_page_t vm_page_alloc_domain(vm_object_t object, vm_pindex_t pindex, int domain, int req) { return (vm_page_alloc_domain_after(object, pindex, domain, req, object != NULL ? vm_radix_lookup_le(&object->rtree, pindex) : NULL)); } /* * Allocate a page in the specified object with the given page index. To * optimize insertion of the page into the object, the caller must also specifiy * the resident page in the object with largest index smaller than the given * page index, or NULL if no such page exists. */ vm_page_t vm_page_alloc_after(vm_object_t object, vm_pindex_t pindex, int req, vm_page_t mpred) { struct vm_domainset_iter di; vm_page_t m; int domain; vm_domainset_iter_page_init(&di, object, pindex, &domain, &req); do { m = vm_page_alloc_domain_after(object, pindex, domain, req, mpred); if (m != NULL) break; } while (vm_domainset_iter_page(&di, object, &domain) == 0); return (m); } /* * Returns true if the number of free pages exceeds the minimum * for the request class and false otherwise. */ int vm_domain_allocate(struct vm_domain *vmd, int req, int npages) { u_int limit, old, new; req = req & VM_ALLOC_CLASS_MASK; /* * The page daemon is allowed to dig deeper into the free page list. */ if (curproc == pageproc && req != VM_ALLOC_INTERRUPT) req = VM_ALLOC_SYSTEM; if (req == VM_ALLOC_INTERRUPT) limit = 0; else if (req == VM_ALLOC_SYSTEM) limit = vmd->vmd_interrupt_free_min; else limit = vmd->vmd_free_reserved; /* * Attempt to reserve the pages. Fail if we're below the limit. */ limit += npages; old = vmd->vmd_free_count; do { if (old < limit) return (0); new = old - npages; } while (atomic_fcmpset_int(&vmd->vmd_free_count, &old, new) == 0); /* Wake the page daemon if we've crossed the threshold. */ if (vm_paging_needed(vmd, new) && !vm_paging_needed(vmd, old)) pagedaemon_wakeup(vmd->vmd_domain); /* Only update bitsets on transitions. */ if ((old >= vmd->vmd_free_min && new < vmd->vmd_free_min) || (old >= vmd->vmd_free_severe && new < vmd->vmd_free_severe)) vm_domain_set(vmd); return (1); } vm_page_t vm_page_alloc_domain_after(vm_object_t object, vm_pindex_t pindex, int domain, int req, vm_page_t mpred) { struct vm_domain *vmd; vm_page_t m; int flags, pool; KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), ("inconsistent object(%p)/req(%x)", object, req)); KASSERT(object == NULL || (req & VM_ALLOC_WAITOK) == 0, ("Can't sleep and retry object insertion.")); KASSERT(mpred == NULL || mpred->pindex < pindex, ("mpred %p doesn't precede pindex 0x%jx", mpred, (uintmax_t)pindex)); if (object != NULL) VM_OBJECT_ASSERT_WLOCKED(object); flags = 0; m = NULL; pool = object != NULL ? VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT; again: #if VM_NRESERVLEVEL > 0 /* * Can we allocate the page from a reservation? */ if (vm_object_reserv(object) && (m = vm_reserv_alloc_page(object, pindex, domain, req, mpred)) != NULL) { domain = vm_phys_domain(m); vmd = VM_DOMAIN(domain); goto found; } #endif vmd = VM_DOMAIN(domain); if (vmd->vmd_pgcache[pool].zone != NULL) { m = uma_zalloc(vmd->vmd_pgcache[pool].zone, M_NOWAIT); if (m != NULL) { flags |= PG_PCPU_CACHE; goto found; } } if (vm_domain_allocate(vmd, req, 1)) { /* * If not, allocate it from the free page queues. */ vm_domain_free_lock(vmd); m = vm_phys_alloc_pages(domain, pool, 0); vm_domain_free_unlock(vmd); if (m == NULL) { vm_domain_freecnt_inc(vmd, 1); #if VM_NRESERVLEVEL > 0 if (vm_reserv_reclaim_inactive(domain)) goto again; #endif } } if (m == NULL) { /* * Not allocatable, give up. */ if (vm_domain_alloc_fail(vmd, object, req)) goto again; return (NULL); } /* * At this point we had better have found a good page. */ found: vm_page_dequeue(m); vm_page_alloc_check(m); /* * Initialize the page. Only the PG_ZERO flag is inherited. */ if ((req & VM_ALLOC_ZERO) != 0) flags |= (m->flags & PG_ZERO); if ((req & VM_ALLOC_NODUMP) != 0) flags |= PG_NODUMP; m->flags = flags; m->aflags = 0; m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ? VPO_UNMANAGED : 0; m->busy_lock = VPB_UNBUSIED; if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0) m->busy_lock = VPB_SINGLE_EXCLUSIVER; if ((req & VM_ALLOC_SBUSY) != 0) m->busy_lock = VPB_SHARERS_WORD(1); if (req & VM_ALLOC_WIRED) { /* * The page lock is not required for wiring a page until that * page is inserted into the object. */ vm_wire_add(1); m->ref_count = 1; } m->act_count = 0; if (object != NULL) { if (vm_page_insert_after(m, object, pindex, mpred)) { if (req & VM_ALLOC_WIRED) { vm_wire_sub(1); m->ref_count = 0; } KASSERT(m->object == NULL, ("page %p has object", m)); m->oflags = VPO_UNMANAGED; m->busy_lock = VPB_UNBUSIED; /* Don't change PG_ZERO. */ vm_page_free_toq(m); if (req & VM_ALLOC_WAITFAIL) { VM_OBJECT_WUNLOCK(object); vm_radix_wait(); VM_OBJECT_WLOCK(object); } return (NULL); } /* Ignore device objects; the pager sets "memattr" for them. */ if (object->memattr != VM_MEMATTR_DEFAULT && (object->flags & OBJ_FICTITIOUS) == 0) pmap_page_set_memattr(m, object->memattr); } else m->pindex = pindex; return (m); } /* * vm_page_alloc_contig: * * Allocate a contiguous set of physical pages of the given size "npages" * from the free lists. All of the physical pages must be at or above * the given physical address "low" and below the given physical address * "high". The given value "alignment" determines the alignment of the * first physical page in the set. If the given value "boundary" is * non-zero, then the set of physical pages cannot cross any physical * address boundary that is a multiple of that value. Both "alignment" * and "boundary" must be a power of two. * * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT, * then the memory attribute setting for the physical pages is configured * to the object's memory attribute setting. Otherwise, the memory * attribute setting for the physical pages is configured to "memattr", * overriding the object's memory attribute setting. However, if the * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the * memory attribute setting for the physical pages cannot be configured * to VM_MEMATTR_DEFAULT. * * The specified object may not contain fictitious pages. * * The caller must always specify an allocation class. * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * * optional allocation flags: * VM_ALLOC_NOBUSY do not exclusive busy the page * VM_ALLOC_NODUMP do not include the page in a kernel core dump * VM_ALLOC_NOOBJ page is not associated with an object and * should not be exclusive busy * VM_ALLOC_SBUSY shared busy the allocated page * VM_ALLOC_WIRED wire the allocated page * VM_ALLOC_ZERO prefer a zeroed page */ vm_page_t vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, vm_memattr_t memattr) { struct vm_domainset_iter di; vm_page_t m; int domain; vm_domainset_iter_page_init(&di, object, pindex, &domain, &req); do { m = vm_page_alloc_contig_domain(object, pindex, domain, req, npages, low, high, alignment, boundary, memattr); if (m != NULL) break; } while (vm_domainset_iter_page(&di, object, &domain) == 0); return (m); } vm_page_t vm_page_alloc_contig_domain(vm_object_t object, vm_pindex_t pindex, int domain, int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, vm_memattr_t memattr) { struct vm_domain *vmd; vm_page_t m, m_ret, mpred; u_int busy_lock, flags, oflags; mpred = NULL; /* XXX: pacify gcc */ KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), ("vm_page_alloc_contig: inconsistent object(%p)/req(%x)", object, req)); KASSERT(object == NULL || (req & VM_ALLOC_WAITOK) == 0, ("Can't sleep and retry object insertion.")); if (object != NULL) { VM_OBJECT_ASSERT_WLOCKED(object); KASSERT((object->flags & OBJ_FICTITIOUS) == 0, ("vm_page_alloc_contig: object %p has fictitious pages", object)); } KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); if (object != NULL) { mpred = vm_radix_lookup_le(&object->rtree, pindex); KASSERT(mpred == NULL || mpred->pindex != pindex, ("vm_page_alloc_contig: pindex already allocated")); } /* * Can we allocate the pages without the number of free pages falling * below the lower bound for the allocation class? */ m_ret = NULL; again: #if VM_NRESERVLEVEL > 0 /* * Can we allocate the pages from a reservation? */ if (vm_object_reserv(object) && (m_ret = vm_reserv_alloc_contig(object, pindex, domain, req, mpred, npages, low, high, alignment, boundary)) != NULL) { domain = vm_phys_domain(m_ret); vmd = VM_DOMAIN(domain); goto found; } #endif vmd = VM_DOMAIN(domain); if (vm_domain_allocate(vmd, req, npages)) { /* * allocate them from the free page queues. */ vm_domain_free_lock(vmd); m_ret = vm_phys_alloc_contig(domain, npages, low, high, alignment, boundary); vm_domain_free_unlock(vmd); if (m_ret == NULL) { vm_domain_freecnt_inc(vmd, npages); #if VM_NRESERVLEVEL > 0 if (vm_reserv_reclaim_contig(domain, npages, low, high, alignment, boundary)) goto again; #endif } } if (m_ret == NULL) { if (vm_domain_alloc_fail(vmd, object, req)) goto again; return (NULL); } #if VM_NRESERVLEVEL > 0 found: #endif for (m = m_ret; m < &m_ret[npages]; m++) { vm_page_dequeue(m); vm_page_alloc_check(m); } /* * Initialize the pages. Only the PG_ZERO flag is inherited. */ flags = 0; if ((req & VM_ALLOC_ZERO) != 0) flags = PG_ZERO; if ((req & VM_ALLOC_NODUMP) != 0) flags |= PG_NODUMP; oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ? VPO_UNMANAGED : 0; busy_lock = VPB_UNBUSIED; if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0) busy_lock = VPB_SINGLE_EXCLUSIVER; if ((req & VM_ALLOC_SBUSY) != 0) busy_lock = VPB_SHARERS_WORD(1); if ((req & VM_ALLOC_WIRED) != 0) vm_wire_add(npages); if (object != NULL) { if (object->memattr != VM_MEMATTR_DEFAULT && memattr == VM_MEMATTR_DEFAULT) memattr = object->memattr; } for (m = m_ret; m < &m_ret[npages]; m++) { m->aflags = 0; m->flags = (m->flags | PG_NODUMP) & flags; m->busy_lock = busy_lock; if ((req & VM_ALLOC_WIRED) != 0) m->ref_count = 1; m->act_count = 0; m->oflags = oflags; if (object != NULL) { if (vm_page_insert_after(m, object, pindex, mpred)) { if ((req & VM_ALLOC_WIRED) != 0) vm_wire_sub(npages); KASSERT(m->object == NULL, ("page %p has object", m)); mpred = m; for (m = m_ret; m < &m_ret[npages]; m++) { if (m <= mpred && (req & VM_ALLOC_WIRED) != 0) m->ref_count = 0; m->oflags = VPO_UNMANAGED; m->busy_lock = VPB_UNBUSIED; /* Don't change PG_ZERO. */ vm_page_free_toq(m); } if (req & VM_ALLOC_WAITFAIL) { VM_OBJECT_WUNLOCK(object); vm_radix_wait(); VM_OBJECT_WLOCK(object); } return (NULL); } mpred = m; } else m->pindex = pindex; if (memattr != VM_MEMATTR_DEFAULT) pmap_page_set_memattr(m, memattr); pindex++; } return (m_ret); } /* * Check a page that has been freshly dequeued from a freelist. */ static void vm_page_alloc_check(vm_page_t m) { KASSERT(m->object == NULL, ("page %p has object", m)); KASSERT(m->queue == PQ_NONE && (m->aflags & PGA_QUEUE_STATE_MASK) == 0, ("page %p has unexpected queue %d, flags %#x", m, m->queue, (m->aflags & PGA_QUEUE_STATE_MASK))); KASSERT(m->ref_count == 0, ("page %p has references", m)); KASSERT(!vm_page_busied(m), ("page %p is busy", m)); KASSERT(m->dirty == 0, ("page %p is dirty", m)); KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, ("page %p has unexpected memattr %d", m, pmap_page_get_memattr(m))); KASSERT(m->valid == 0, ("free page %p is valid", m)); } /* * vm_page_alloc_freelist: * * Allocate a physical page from the specified free page list. * * The caller must always specify an allocation class. * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * * optional allocation flags: * VM_ALLOC_COUNT(number) the number of additional pages that the caller * intends to allocate * VM_ALLOC_WIRED wire the allocated page * VM_ALLOC_ZERO prefer a zeroed page */ vm_page_t vm_page_alloc_freelist(int freelist, int req) { struct vm_domainset_iter di; vm_page_t m; int domain; vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req); do { m = vm_page_alloc_freelist_domain(domain, freelist, req); if (m != NULL) break; } while (vm_domainset_iter_page(&di, NULL, &domain) == 0); return (m); } vm_page_t vm_page_alloc_freelist_domain(int domain, int freelist, int req) { struct vm_domain *vmd; vm_page_t m; u_int flags; m = NULL; vmd = VM_DOMAIN(domain); again: if (vm_domain_allocate(vmd, req, 1)) { vm_domain_free_lock(vmd); m = vm_phys_alloc_freelist_pages(domain, freelist, VM_FREEPOOL_DIRECT, 0); vm_domain_free_unlock(vmd); if (m == NULL) vm_domain_freecnt_inc(vmd, 1); } if (m == NULL) { if (vm_domain_alloc_fail(vmd, NULL, req)) goto again; return (NULL); } vm_page_dequeue(m); vm_page_alloc_check(m); /* * Initialize the page. Only the PG_ZERO flag is inherited. */ m->aflags = 0; flags = 0; if ((req & VM_ALLOC_ZERO) != 0) flags = PG_ZERO; m->flags &= flags; if ((req & VM_ALLOC_WIRED) != 0) { /* * The page lock is not required for wiring a page that does * not belong to an object. */ vm_wire_add(1); m->ref_count = 1; } /* Unmanaged pages don't use "act_count". */ m->oflags = VPO_UNMANAGED; return (m); } static int vm_page_zone_import(void *arg, void **store, int cnt, int domain, int flags) { struct vm_domain *vmd; struct vm_pgcache *pgcache; int i; pgcache = arg; vmd = VM_DOMAIN(pgcache->domain); /* Only import if we can bring in a full bucket. */ if (cnt == 1 || !vm_domain_allocate(vmd, VM_ALLOC_NORMAL, cnt)) return (0); domain = vmd->vmd_domain; vm_domain_free_lock(vmd); i = vm_phys_alloc_npages(domain, pgcache->pool, cnt, (vm_page_t *)store); vm_domain_free_unlock(vmd); if (cnt != i) vm_domain_freecnt_inc(vmd, cnt - i); return (i); } static void vm_page_zone_release(void *arg, void **store, int cnt) { struct vm_domain *vmd; struct vm_pgcache *pgcache; vm_page_t m; int i; pgcache = arg; vmd = VM_DOMAIN(pgcache->domain); vm_domain_free_lock(vmd); for (i = 0; i < cnt; i++) { m = (vm_page_t)store[i]; vm_phys_free_pages(m, 0); } vm_domain_free_unlock(vmd); vm_domain_freecnt_inc(vmd, cnt); } #define VPSC_ANY 0 /* No restrictions. */ #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */ #define VPSC_NOSUPER 2 /* Skip superpages. */ /* * vm_page_scan_contig: * * Scan vm_page_array[] between the specified entries "m_start" and * "m_end" for a run of contiguous physical pages that satisfy the * specified conditions, and return the lowest page in the run. The * specified "alignment" determines the alignment of the lowest physical * page in the run. If the specified "boundary" is non-zero, then the * run of physical pages cannot span a physical address that is a * multiple of "boundary". * * "m_end" is never dereferenced, so it need not point to a vm_page * structure within vm_page_array[]. * * "npages" must be greater than zero. "m_start" and "m_end" must not * span a hole (or discontiguity) in the physical address space. Both * "alignment" and "boundary" must be a power of two. */ vm_page_t vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end, u_long alignment, vm_paddr_t boundary, int options) { struct mtx *m_mtx; vm_object_t object; vm_paddr_t pa; vm_page_t m, m_run; #if VM_NRESERVLEVEL > 0 int level; #endif int m_inc, order, run_ext, run_len; KASSERT(npages > 0, ("npages is 0")); KASSERT(powerof2(alignment), ("alignment is not a power of 2")); KASSERT(powerof2(boundary), ("boundary is not a power of 2")); m_run = NULL; run_len = 0; m_mtx = NULL; for (m = m_start; m < m_end && run_len < npages; m += m_inc) { KASSERT((m->flags & PG_MARKER) == 0, ("page %p is PG_MARKER", m)); KASSERT((m->flags & PG_FICTITIOUS) == 0 || m->ref_count >= 1, ("fictitious page %p has invalid ref count", m)); /* * If the current page would be the start of a run, check its * physical address against the end, alignment, and boundary * conditions. If it doesn't satisfy these conditions, either * terminate the scan or advance to the next page that * satisfies the failed condition. */ if (run_len == 0) { KASSERT(m_run == NULL, ("m_run != NULL")); if (m + npages > m_end) break; pa = VM_PAGE_TO_PHYS(m); if ((pa & (alignment - 1)) != 0) { m_inc = atop(roundup2(pa, alignment) - pa); continue; } if (rounddown2(pa ^ (pa + ptoa(npages) - 1), boundary) != 0) { m_inc = atop(roundup2(pa, boundary) - pa); continue; } } else KASSERT(m_run != NULL, ("m_run == NULL")); vm_page_change_lock(m, &m_mtx); m_inc = 1; retry: if (vm_page_wired(m)) run_ext = 0; #if VM_NRESERVLEVEL > 0 else if ((level = vm_reserv_level(m)) >= 0 && (options & VPSC_NORESERV) != 0) { run_ext = 0; /* Advance to the end of the reservation. */ pa = VM_PAGE_TO_PHYS(m); m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) - pa); } #endif else if ((object = m->object) != NULL) { /* * The page is considered eligible for relocation if * and only if it could be laundered or reclaimed by * the page daemon. */ if (!VM_OBJECT_TRYRLOCK(object)) { mtx_unlock(m_mtx); VM_OBJECT_RLOCK(object); mtx_lock(m_mtx); if (m->object != object) { /* * The page may have been freed. */ VM_OBJECT_RUNLOCK(object); goto retry; } } /* Don't care: PG_NODUMP, PG_ZERO. */ if (object->type != OBJT_DEFAULT && object->type != OBJT_SWAP && object->type != OBJT_VNODE) { run_ext = 0; #if VM_NRESERVLEVEL > 0 } else if ((options & VPSC_NOSUPER) != 0 && (level = vm_reserv_level_iffullpop(m)) >= 0) { run_ext = 0; /* Advance to the end of the superpage. */ pa = VM_PAGE_TO_PHYS(m); m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) - pa); #endif } else if (object->memattr == VM_MEMATTR_DEFAULT && vm_page_queue(m) != PQ_NONE && !vm_page_busied(m) && !vm_page_wired(m)) { /* * The page is allocated but eligible for * relocation. Extend the current run by one * page. */ KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, ("page %p has an unexpected memattr", m)); KASSERT((m->oflags & (VPO_SWAPINPROG | VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, ("page %p has unexpected oflags", m)); /* Don't care: PGA_NOSYNC. */ run_ext = 1; } else run_ext = 0; VM_OBJECT_RUNLOCK(object); #if VM_NRESERVLEVEL > 0 } else if (level >= 0) { /* * The page is reserved but not yet allocated. In * other words, it is still free. Extend the current * run by one page. */ run_ext = 1; #endif } else if ((order = m->order) < VM_NFREEORDER) { /* * The page is enqueued in the physical memory * allocator's free page queues. Moreover, it is the * first page in a power-of-two-sized run of * contiguous free pages. Add these pages to the end * of the current run, and jump ahead. */ run_ext = 1 << order; m_inc = 1 << order; } else { /* * Skip the page for one of the following reasons: (1) * It is enqueued in the physical memory allocator's * free page queues. However, it is not the first * page in a run of contiguous free pages. (This case * rarely occurs because the scan is performed in * ascending order.) (2) It is not reserved, and it is * transitioning from free to allocated. (Conversely, * the transition from allocated to free for managed * pages is blocked by the page lock.) (3) It is * allocated but not contained by an object and not * wired, e.g., allocated by Xen's balloon driver. */ run_ext = 0; } /* * Extend or reset the current run of pages. */ if (run_ext > 0) { if (run_len == 0) m_run = m; run_len += run_ext; } else { if (run_len > 0) { m_run = NULL; run_len = 0; } } } if (m_mtx != NULL) mtx_unlock(m_mtx); if (run_len >= npages) return (m_run); return (NULL); } /* * vm_page_reclaim_run: * * Try to relocate each of the allocated virtual pages within the * specified run of physical pages to a new physical address. Free the * physical pages underlying the relocated virtual pages. A virtual page * is relocatable if and only if it could be laundered or reclaimed by * the page daemon. Whenever possible, a virtual page is relocated to a * physical address above "high". * * Returns 0 if every physical page within the run was already free or * just freed by a successful relocation. Otherwise, returns a non-zero * value indicating why the last attempt to relocate a virtual page was * unsuccessful. * * "req_class" must be an allocation class. */ static int vm_page_reclaim_run(int req_class, int domain, u_long npages, vm_page_t m_run, vm_paddr_t high) { struct vm_domain *vmd; struct mtx *m_mtx; struct spglist free; vm_object_t object; vm_paddr_t pa; vm_page_t m, m_end, m_new; int error, order, req; KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class, ("req_class is not an allocation class")); SLIST_INIT(&free); error = 0; m = m_run; m_end = m_run + npages; m_mtx = NULL; for (; error == 0 && m < m_end; m++) { KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, ("page %p is PG_FICTITIOUS or PG_MARKER", m)); /* * Avoid releasing and reacquiring the same page lock. */ vm_page_change_lock(m, &m_mtx); retry: /* * Racily check for wirings. Races are handled below. */ if (vm_page_wired(m)) error = EBUSY; else if ((object = m->object) != NULL) { /* * The page is relocated if and only if it could be * laundered or reclaimed by the page daemon. */ if (!VM_OBJECT_TRYWLOCK(object)) { mtx_unlock(m_mtx); VM_OBJECT_WLOCK(object); mtx_lock(m_mtx); if (m->object != object) { /* * The page may have been freed. */ VM_OBJECT_WUNLOCK(object); goto retry; } } /* Don't care: PG_NODUMP, PG_ZERO. */ if (object->type != OBJT_DEFAULT && object->type != OBJT_SWAP && object->type != OBJT_VNODE) error = EINVAL; else if (object->memattr != VM_MEMATTR_DEFAULT) error = EINVAL; else if (vm_page_queue(m) != PQ_NONE && vm_page_tryxbusy(m) != 0) { if (vm_page_wired(m)) { vm_page_xunbusy(m); error = EBUSY; goto unlock; } KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, ("page %p has an unexpected memattr", m)); KASSERT((m->oflags & (VPO_SWAPINPROG | VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, ("page %p has unexpected oflags", m)); /* Don't care: PGA_NOSYNC. */ if (!vm_page_none_valid(m)) { /* * First, try to allocate a new page * that is above "high". Failing * that, try to allocate a new page * that is below "m_run". Allocate * the new page between the end of * "m_run" and "high" only as a last * resort. */ req = req_class | VM_ALLOC_NOOBJ; if ((m->flags & PG_NODUMP) != 0) req |= VM_ALLOC_NODUMP; if (trunc_page(high) != ~(vm_paddr_t)PAGE_MASK) { m_new = vm_page_alloc_contig( NULL, 0, req, 1, round_page(high), ~(vm_paddr_t)0, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT); } else m_new = NULL; if (m_new == NULL) { pa = VM_PAGE_TO_PHYS(m_run); m_new = vm_page_alloc_contig( NULL, 0, req, 1, 0, pa - 1, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT); } if (m_new == NULL) { pa += ptoa(npages); m_new = vm_page_alloc_contig( NULL, 0, req, 1, pa, high, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT); } if (m_new == NULL) { vm_page_xunbusy(m); error = ENOMEM; goto unlock; } /* * Unmap the page and check for new * wirings that may have been acquired * through a pmap lookup. */ if (object->ref_count != 0 && !vm_page_try_remove_all(m)) { vm_page_free(m_new); error = EBUSY; goto unlock; } /* * Replace "m" with the new page. For * vm_page_replace(), "m" must be busy * and dequeued. Finally, change "m" * as if vm_page_free() was called. */ m_new->aflags = m->aflags & ~PGA_QUEUE_STATE_MASK; KASSERT(m_new->oflags == VPO_UNMANAGED, ("page %p is managed", m_new)); pmap_copy_page(m, m_new); m_new->valid = m->valid; m_new->dirty = m->dirty; m->flags &= ~PG_ZERO; vm_page_dequeue(m); vm_page_replace_checked(m_new, object, m->pindex, m); if (vm_page_free_prep(m)) SLIST_INSERT_HEAD(&free, m, plinks.s.ss); /* * The new page must be deactivated * before the object is unlocked. */ vm_page_change_lock(m_new, &m_mtx); vm_page_deactivate(m_new); } else { m->flags &= ~PG_ZERO; vm_page_dequeue(m); if (vm_page_free_prep(m)) SLIST_INSERT_HEAD(&free, m, plinks.s.ss); KASSERT(m->dirty == 0, ("page %p is dirty", m)); } } else error = EBUSY; unlock: VM_OBJECT_WUNLOCK(object); } else { MPASS(vm_phys_domain(m) == domain); vmd = VM_DOMAIN(domain); vm_domain_free_lock(vmd); order = m->order; if (order < VM_NFREEORDER) { /* * The page is enqueued in the physical memory * allocator's free page queues. Moreover, it * is the first page in a power-of-two-sized * run of contiguous free pages. Jump ahead * to the last page within that run, and * continue from there. */ m += (1 << order) - 1; } #if VM_NRESERVLEVEL > 0 else if (vm_reserv_is_page_free(m)) order = 0; #endif vm_domain_free_unlock(vmd); if (order == VM_NFREEORDER) error = EINVAL; } } if (m_mtx != NULL) mtx_unlock(m_mtx); if ((m = SLIST_FIRST(&free)) != NULL) { int cnt; vmd = VM_DOMAIN(domain); cnt = 0; vm_domain_free_lock(vmd); do { MPASS(vm_phys_domain(m) == domain); SLIST_REMOVE_HEAD(&free, plinks.s.ss); vm_phys_free_pages(m, 0); cnt++; } while ((m = SLIST_FIRST(&free)) != NULL); vm_domain_free_unlock(vmd); vm_domain_freecnt_inc(vmd, cnt); } return (error); } #define NRUNS 16 CTASSERT(powerof2(NRUNS)); #define RUN_INDEX(count) ((count) & (NRUNS - 1)) #define MIN_RECLAIM 8 /* * vm_page_reclaim_contig: * * Reclaim allocated, contiguous physical memory satisfying the specified * conditions by relocating the virtual pages using that physical memory. * Returns true if reclamation is successful and false otherwise. Since * relocation requires the allocation of physical pages, reclamation may * fail due to a shortage of free pages. When reclamation fails, callers * are expected to perform vm_wait() before retrying a failed allocation * operation, e.g., vm_page_alloc_contig(). * * The caller must always specify an allocation class through "req". * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * * The optional allocation flags are ignored. * * "npages" must be greater than zero. Both "alignment" and "boundary" * must be a power of two. */ bool vm_page_reclaim_contig_domain(int domain, int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary) { struct vm_domain *vmd; vm_paddr_t curr_low; vm_page_t m_run, m_runs[NRUNS]; u_long count, reclaimed; int error, i, options, req_class; KASSERT(npages > 0, ("npages is 0")); KASSERT(powerof2(alignment), ("alignment is not a power of 2")); KASSERT(powerof2(boundary), ("boundary is not a power of 2")); req_class = req & VM_ALLOC_CLASS_MASK; /* * The page daemon is allowed to dig deeper into the free page list. */ if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) req_class = VM_ALLOC_SYSTEM; /* * Return if the number of free pages cannot satisfy the requested * allocation. */ vmd = VM_DOMAIN(domain); count = vmd->vmd_free_count; if (count < npages + vmd->vmd_free_reserved || (count < npages + vmd->vmd_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) || (count < npages && req_class == VM_ALLOC_INTERRUPT)) return (false); /* * Scan up to three times, relaxing the restrictions ("options") on * the reclamation of reservations and superpages each time. */ for (options = VPSC_NORESERV;;) { /* * Find the highest runs that satisfy the given constraints * and restrictions, and record them in "m_runs". */ curr_low = low; count = 0; for (;;) { m_run = vm_phys_scan_contig(domain, npages, curr_low, high, alignment, boundary, options); if (m_run == NULL) break; curr_low = VM_PAGE_TO_PHYS(m_run) + ptoa(npages); m_runs[RUN_INDEX(count)] = m_run; count++; } /* * Reclaim the highest runs in LIFO (descending) order until * the number of reclaimed pages, "reclaimed", is at least * MIN_RECLAIM. Reset "reclaimed" each time because each * reclamation is idempotent, and runs will (likely) recur * from one scan to the next as restrictions are relaxed. */ reclaimed = 0; for (i = 0; count > 0 && i < NRUNS; i++) { count--; m_run = m_runs[RUN_INDEX(count)]; error = vm_page_reclaim_run(req_class, domain, npages, m_run, high); if (error == 0) { reclaimed += npages; if (reclaimed >= MIN_RECLAIM) return (true); } } /* * Either relax the restrictions on the next scan or return if * the last scan had no restrictions. */ if (options == VPSC_NORESERV) options = VPSC_NOSUPER; else if (options == VPSC_NOSUPER) options = VPSC_ANY; else if (options == VPSC_ANY) return (reclaimed != 0); } } bool vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary) { struct vm_domainset_iter di; int domain; bool ret; vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req); do { ret = vm_page_reclaim_contig_domain(domain, req, npages, low, high, alignment, boundary); if (ret) break; } while (vm_domainset_iter_page(&di, NULL, &domain) == 0); return (ret); } /* * Set the domain in the appropriate page level domainset. */ void vm_domain_set(struct vm_domain *vmd) { mtx_lock(&vm_domainset_lock); if (!vmd->vmd_minset && vm_paging_min(vmd)) { vmd->vmd_minset = 1; DOMAINSET_SET(vmd->vmd_domain, &vm_min_domains); } if (!vmd->vmd_severeset && vm_paging_severe(vmd)) { vmd->vmd_severeset = 1; DOMAINSET_SET(vmd->vmd_domain, &vm_severe_domains); } mtx_unlock(&vm_domainset_lock); } /* * Clear the domain from the appropriate page level domainset. */ void vm_domain_clear(struct vm_domain *vmd) { mtx_lock(&vm_domainset_lock); if (vmd->vmd_minset && !vm_paging_min(vmd)) { vmd->vmd_minset = 0; DOMAINSET_CLR(vmd->vmd_domain, &vm_min_domains); if (vm_min_waiters != 0) { vm_min_waiters = 0; wakeup(&vm_min_domains); } } if (vmd->vmd_severeset && !vm_paging_severe(vmd)) { vmd->vmd_severeset = 0; DOMAINSET_CLR(vmd->vmd_domain, &vm_severe_domains); if (vm_severe_waiters != 0) { vm_severe_waiters = 0; wakeup(&vm_severe_domains); } } /* * If pageout daemon needs pages, then tell it that there are * some free. */ if (vmd->vmd_pageout_pages_needed && vmd->vmd_free_count >= vmd->vmd_pageout_free_min) { wakeup(&vmd->vmd_pageout_pages_needed); vmd->vmd_pageout_pages_needed = 0; } /* See comments in vm_wait_doms(). */ if (vm_pageproc_waiters) { vm_pageproc_waiters = 0; wakeup(&vm_pageproc_waiters); } mtx_unlock(&vm_domainset_lock); } /* * Wait for free pages to exceed the min threshold globally. */ void vm_wait_min(void) { mtx_lock(&vm_domainset_lock); while (vm_page_count_min()) { vm_min_waiters++; msleep(&vm_min_domains, &vm_domainset_lock, PVM, "vmwait", 0); } mtx_unlock(&vm_domainset_lock); } /* * Wait for free pages to exceed the severe threshold globally. */ void vm_wait_severe(void) { mtx_lock(&vm_domainset_lock); while (vm_page_count_severe()) { vm_severe_waiters++; msleep(&vm_severe_domains, &vm_domainset_lock, PVM, "vmwait", 0); } mtx_unlock(&vm_domainset_lock); } u_int vm_wait_count(void) { return (vm_severe_waiters + vm_min_waiters + vm_pageproc_waiters); } void vm_wait_doms(const domainset_t *wdoms) { /* * We use racey wakeup synchronization to avoid expensive global * locking for the pageproc when sleeping with a non-specific vm_wait. * To handle this, we only sleep for one tick in this instance. It * is expected that most allocations for the pageproc will come from * kmem or vm_page_grab* which will use the more specific and * race-free vm_wait_domain(). */ if (curproc == pageproc) { mtx_lock(&vm_domainset_lock); vm_pageproc_waiters++; msleep(&vm_pageproc_waiters, &vm_domainset_lock, PVM | PDROP, "pageprocwait", 1); } else { /* * XXX Ideally we would wait only until the allocation could * be satisfied. This condition can cause new allocators to * consume all freed pages while old allocators wait. */ mtx_lock(&vm_domainset_lock); if (vm_page_count_min_set(wdoms)) { vm_min_waiters++; msleep(&vm_min_domains, &vm_domainset_lock, PVM | PDROP, "vmwait", 0); } else mtx_unlock(&vm_domainset_lock); } } /* * vm_wait_domain: * * Sleep until free pages are available for allocation. * - Called in various places after failed memory allocations. */ void vm_wait_domain(int domain) { struct vm_domain *vmd; domainset_t wdom; vmd = VM_DOMAIN(domain); vm_domain_free_assert_unlocked(vmd); if (curproc == pageproc) { mtx_lock(&vm_domainset_lock); if (vmd->vmd_free_count < vmd->vmd_pageout_free_min) { vmd->vmd_pageout_pages_needed = 1; msleep(&vmd->vmd_pageout_pages_needed, &vm_domainset_lock, PDROP | PSWP, "VMWait", 0); } else mtx_unlock(&vm_domainset_lock); } else { if (pageproc == NULL) panic("vm_wait in early boot"); DOMAINSET_ZERO(&wdom); DOMAINSET_SET(vmd->vmd_domain, &wdom); vm_wait_doms(&wdom); } } /* * vm_wait: * * Sleep until free pages are available for allocation in the * affinity domains of the obj. If obj is NULL, the domain set * for the calling thread is used. * Called in various places after failed memory allocations. */ void vm_wait(vm_object_t obj) { struct domainset *d; d = NULL; /* * Carefully fetch pointers only once: the struct domainset * itself is ummutable but the pointer might change. */ if (obj != NULL) d = obj->domain.dr_policy; if (d == NULL) d = curthread->td_domain.dr_policy; vm_wait_doms(&d->ds_mask); } /* * vm_domain_alloc_fail: * * Called when a page allocation function fails. Informs the * pagedaemon and performs the requested wait. Requires the * domain_free and object lock on entry. Returns with the * object lock held and free lock released. Returns an error when * retry is necessary. * */ static int vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object, int req) { vm_domain_free_assert_unlocked(vmd); atomic_add_int(&vmd->vmd_pageout_deficit, max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); if (req & (VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL)) { if (object != NULL) VM_OBJECT_WUNLOCK(object); vm_wait_domain(vmd->vmd_domain); if (object != NULL) VM_OBJECT_WLOCK(object); if (req & VM_ALLOC_WAITOK) return (EAGAIN); } return (0); } /* * vm_waitpfault: * * Sleep until free pages are available for allocation. * - Called only in vm_fault so that processes page faulting * can be easily tracked. * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing * processes will be able to grab memory first. Do not change * this balance without careful testing first. */ void vm_waitpfault(struct domainset *dset, int timo) { /* * XXX Ideally we would wait only until the allocation could * be satisfied. This condition can cause new allocators to * consume all freed pages while old allocators wait. */ mtx_lock(&vm_domainset_lock); if (vm_page_count_min_set(&dset->ds_mask)) { vm_min_waiters++; msleep(&vm_min_domains, &vm_domainset_lock, PUSER | PDROP, "pfault", timo); } else mtx_unlock(&vm_domainset_lock); } static struct vm_pagequeue * vm_page_pagequeue(vm_page_t m) { uint8_t queue; if ((queue = atomic_load_8(&m->queue)) == PQ_NONE) return (NULL); return (&vm_pagequeue_domain(m)->vmd_pagequeues[queue]); } static inline void vm_pqbatch_process_page(struct vm_pagequeue *pq, vm_page_t m) { struct vm_domain *vmd; uint16_t qflags; CRITICAL_ASSERT(curthread); vm_pagequeue_assert_locked(pq); /* * The page daemon is allowed to set m->queue = PQ_NONE without * the page queue lock held. In this case it is about to free the page, * which must not have any queue state. */ qflags = atomic_load_16(&m->aflags); KASSERT(pq == vm_page_pagequeue(m) || (qflags & PGA_QUEUE_STATE_MASK) == 0, ("page %p doesn't belong to queue %p but has aflags %#x", m, pq, qflags)); if ((qflags & PGA_DEQUEUE) != 0) { if (__predict_true((qflags & PGA_ENQUEUED) != 0)) vm_pagequeue_remove(pq, m); vm_page_dequeue_complete(m); counter_u64_add(queue_ops, 1); } else if ((qflags & (PGA_REQUEUE | PGA_REQUEUE_HEAD)) != 0) { if ((qflags & PGA_ENQUEUED) != 0) TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); else { vm_pagequeue_cnt_inc(pq); vm_page_aflag_set(m, PGA_ENQUEUED); } /* * Give PGA_REQUEUE_HEAD precedence over PGA_REQUEUE. * In particular, if both flags are set in close succession, * only PGA_REQUEUE_HEAD will be applied, even if it was set * first. */ if ((qflags & PGA_REQUEUE_HEAD) != 0) { KASSERT(m->queue == PQ_INACTIVE, ("head enqueue not supported for page %p", m)); vmd = vm_pagequeue_domain(m); TAILQ_INSERT_BEFORE(&vmd->vmd_inacthead, m, plinks.q); } else TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); vm_page_aflag_clear(m, qflags & (PGA_REQUEUE | PGA_REQUEUE_HEAD)); counter_u64_add(queue_ops, 1); } else { counter_u64_add(queue_nops, 1); } } static void vm_pqbatch_process(struct vm_pagequeue *pq, struct vm_batchqueue *bq, uint8_t queue) { vm_page_t m; int i; for (i = 0; i < bq->bq_cnt; i++) { m = bq->bq_pa[i]; if (__predict_false(m->queue != queue)) continue; vm_pqbatch_process_page(pq, m); } vm_batchqueue_init(bq); } /* * vm_page_pqbatch_submit: [ internal use only ] * * Enqueue a page in the specified page queue's batched work queue. * The caller must have encoded the requested operation in the page * structure's aflags field. */ void vm_page_pqbatch_submit(vm_page_t m, uint8_t queue) { struct vm_batchqueue *bq; struct vm_pagequeue *pq; int domain; KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("page %p is unmanaged", m)); KASSERT(mtx_owned(vm_page_lockptr(m)) || m->object == NULL, ("missing synchronization for page %p", m)); KASSERT(queue < PQ_COUNT, ("invalid queue %d", queue)); domain = vm_phys_domain(m); pq = &vm_pagequeue_domain(m)->vmd_pagequeues[queue]; critical_enter(); bq = DPCPU_PTR(pqbatch[domain][queue]); if (vm_batchqueue_insert(bq, m)) { critical_exit(); return; } critical_exit(); vm_pagequeue_lock(pq); critical_enter(); bq = DPCPU_PTR(pqbatch[domain][queue]); vm_pqbatch_process(pq, bq, queue); /* * The page may have been logically dequeued before we acquired the * page queue lock. In this case, since we either hold the page lock * or the page is being freed, a different thread cannot be concurrently * enqueuing the page. */ if (__predict_true(m->queue == queue)) vm_pqbatch_process_page(pq, m); else { KASSERT(m->queue == PQ_NONE, ("invalid queue transition for page %p", m)); KASSERT((m->aflags & PGA_ENQUEUED) == 0, ("page %p is enqueued with invalid queue index", m)); } vm_pagequeue_unlock(pq); critical_exit(); } /* * vm_page_pqbatch_drain: [ internal use only ] * * Force all per-CPU page queue batch queues to be drained. This is * intended for use in severe memory shortages, to ensure that pages * do not remain stuck in the batch queues. */ void vm_page_pqbatch_drain(void) { struct thread *td; struct vm_domain *vmd; struct vm_pagequeue *pq; int cpu, domain, queue; td = curthread; CPU_FOREACH(cpu) { thread_lock(td); sched_bind(td, cpu); thread_unlock(td); for (domain = 0; domain < vm_ndomains; domain++) { vmd = VM_DOMAIN(domain); for (queue = 0; queue < PQ_COUNT; queue++) { pq = &vmd->vmd_pagequeues[queue]; vm_pagequeue_lock(pq); critical_enter(); vm_pqbatch_process(pq, DPCPU_PTR(pqbatch[domain][queue]), queue); critical_exit(); vm_pagequeue_unlock(pq); } } } thread_lock(td); sched_unbind(td); thread_unlock(td); } /* * Complete the logical removal of a page from a page queue. We must be * careful to synchronize with the page daemon, which may be concurrently * examining the page with only the page lock held. The page must not be * in a state where it appears to be logically enqueued. */ static void vm_page_dequeue_complete(vm_page_t m) { m->queue = PQ_NONE; atomic_thread_fence_rel(); vm_page_aflag_clear(m, PGA_QUEUE_STATE_MASK); } /* * vm_page_dequeue_deferred: [ internal use only ] * * Request removal of the given page from its current page * queue. Physical removal from the queue may be deferred * indefinitely. * * The page must be locked. */ void vm_page_dequeue_deferred(vm_page_t m) { uint8_t queue; vm_page_assert_locked(m); if ((queue = vm_page_queue(m)) == PQ_NONE) return; /* * Set PGA_DEQUEUE if it is not already set to handle a concurrent call * to vm_page_dequeue_deferred_free(). In particular, avoid modifying * the page's queue state once vm_page_dequeue_deferred_free() has been * called. In the event of a race, two batch queue entries for the page * will be created, but the second will have no effect. */ if (vm_page_pqstate_cmpset(m, queue, queue, PGA_DEQUEUE, PGA_DEQUEUE)) vm_page_pqbatch_submit(m, queue); } /* * A variant of vm_page_dequeue_deferred() that does not assert the page * lock and is only to be called from vm_page_free_prep(). Because the * page is being freed, we can assume that nothing other than the page * daemon is scheduling queue operations on this page, so we get for * free the mutual exclusion that is otherwise provided by the page lock. * To handle races, the page daemon must take care to atomically check * for PGA_DEQUEUE when updating queue state. */ static void vm_page_dequeue_deferred_free(vm_page_t m) { uint8_t queue; KASSERT(m->ref_count == 0, ("page %p has references", m)); for (;;) { if ((m->aflags & PGA_DEQUEUE) != 0) return; atomic_thread_fence_acq(); if ((queue = atomic_load_8(&m->queue)) == PQ_NONE) return; if (vm_page_pqstate_cmpset(m, queue, queue, PGA_DEQUEUE, PGA_DEQUEUE)) { vm_page_pqbatch_submit(m, queue); break; } } } /* * vm_page_dequeue: * * Remove the page from whichever page queue it's in, if any. * The page must either be locked or unallocated. This constraint * ensures that the queue state of the page will remain consistent * after this function returns. */ void vm_page_dequeue(vm_page_t m) { struct vm_pagequeue *pq, *pq1; uint16_t aflags; KASSERT(mtx_owned(vm_page_lockptr(m)) || m->ref_count == 0, ("page %p is allocated and unlocked", m)); for (pq = vm_page_pagequeue(m);; pq = pq1) { if (pq == NULL) { /* * A thread may be concurrently executing * vm_page_dequeue_complete(). Ensure that all queue * state is cleared before we return. */ aflags = atomic_load_16(&m->aflags); if ((aflags & PGA_QUEUE_STATE_MASK) == 0) return; KASSERT((aflags & PGA_DEQUEUE) != 0, ("page %p has unexpected queue state flags %#x", m, aflags)); /* * Busy wait until the thread updating queue state is * finished. Such a thread must be executing in a * critical section. */ cpu_spinwait(); pq1 = vm_page_pagequeue(m); continue; } vm_pagequeue_lock(pq); if ((pq1 = vm_page_pagequeue(m)) == pq) break; vm_pagequeue_unlock(pq); } KASSERT(pq == vm_page_pagequeue(m), ("%s: page %p migrated directly between queues", __func__, m)); KASSERT((m->aflags & PGA_DEQUEUE) != 0 || mtx_owned(vm_page_lockptr(m)), ("%s: queued unlocked page %p", __func__, m)); if ((m->aflags & PGA_ENQUEUED) != 0) vm_pagequeue_remove(pq, m); vm_page_dequeue_complete(m); vm_pagequeue_unlock(pq); } /* * Schedule the given page for insertion into the specified page queue. * Physical insertion of the page may be deferred indefinitely. */ static void vm_page_enqueue(vm_page_t m, uint8_t queue) { vm_page_assert_locked(m); KASSERT(m->queue == PQ_NONE && (m->aflags & PGA_QUEUE_STATE_MASK) == 0, ("%s: page %p is already enqueued", __func__, m)); KASSERT(m->ref_count > 0, ("%s: page %p does not carry any references", __func__, m)); m->queue = queue; if ((m->aflags & PGA_REQUEUE) == 0) vm_page_aflag_set(m, PGA_REQUEUE); vm_page_pqbatch_submit(m, queue); } /* * vm_page_requeue: [ internal use only ] * * Schedule a requeue of the given page. * * The page must be locked. */ void vm_page_requeue(vm_page_t m) { vm_page_assert_locked(m); KASSERT(vm_page_queue(m) != PQ_NONE, ("%s: page %p is not logically enqueued", __func__, m)); KASSERT(m->ref_count > 0, ("%s: page %p does not carry any references", __func__, m)); if ((m->aflags & PGA_REQUEUE) == 0) vm_page_aflag_set(m, PGA_REQUEUE); vm_page_pqbatch_submit(m, atomic_load_8(&m->queue)); } /* * vm_page_swapqueue: [ internal use only ] * * Move the page from one queue to another, or to the tail of its * current queue, in the face of a possible concurrent call to * vm_page_dequeue_deferred_free(). */ void vm_page_swapqueue(vm_page_t m, uint8_t oldq, uint8_t newq) { struct vm_pagequeue *pq; vm_page_t next; bool queued; KASSERT(oldq < PQ_COUNT && newq < PQ_COUNT && oldq != newq, ("vm_page_swapqueue: invalid queues (%d, %d)", oldq, newq)); vm_page_assert_locked(m); pq = &vm_pagequeue_domain(m)->vmd_pagequeues[oldq]; vm_pagequeue_lock(pq); /* * The physical queue state might change at any point before the page * queue lock is acquired, so we must verify that we hold the correct * lock before proceeding. */ if (__predict_false(m->queue != oldq)) { vm_pagequeue_unlock(pq); return; } /* * Once the queue index of the page changes, there is nothing * synchronizing with further updates to the physical queue state. * Therefore we must remove the page from the queue now in anticipation * of a successful commit, and be prepared to roll back. */ if (__predict_true((m->aflags & PGA_ENQUEUED) != 0)) { next = TAILQ_NEXT(m, plinks.q); TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); vm_page_aflag_clear(m, PGA_ENQUEUED); queued = true; } else { queued = false; } /* * Atomically update the queue field and set PGA_REQUEUE while * ensuring that PGA_DEQUEUE has not been set. */ if (__predict_false(!vm_page_pqstate_cmpset(m, oldq, newq, PGA_DEQUEUE, PGA_REQUEUE))) { if (queued) { vm_page_aflag_set(m, PGA_ENQUEUED); if (next != NULL) TAILQ_INSERT_BEFORE(next, m, plinks.q); else TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); } vm_pagequeue_unlock(pq); return; } vm_pagequeue_cnt_dec(pq); vm_pagequeue_unlock(pq); vm_page_pqbatch_submit(m, newq); } /* * vm_page_free_prep: * * Prepares the given page to be put on the free list, * disassociating it from any VM object. The caller may return * the page to the free list only if this function returns true. * * The object must be locked. The page must be locked if it is * managed. */ bool vm_page_free_prep(vm_page_t m) { /* * Synchronize with threads that have dropped a reference to this * page. */ atomic_thread_fence_acq(); #if defined(DIAGNOSTIC) && defined(PHYS_TO_DMAP) if (PMAP_HAS_DMAP && (m->flags & PG_ZERO) != 0) { uint64_t *p; int i; p = (uint64_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)); for (i = 0; i < PAGE_SIZE / sizeof(uint64_t); i++, p++) KASSERT(*p == 0, ("vm_page_free_prep %p PG_ZERO %d %jx", m, i, (uintmax_t)*p)); } #endif if ((m->oflags & VPO_UNMANAGED) == 0) { KASSERT(!pmap_page_is_mapped(m), ("vm_page_free_prep: freeing mapped page %p", m)); KASSERT((m->aflags & (PGA_EXECUTABLE | PGA_WRITEABLE)) == 0, ("vm_page_free_prep: mapping flags set in page %p", m)); } else { KASSERT(m->queue == PQ_NONE, ("vm_page_free_prep: unmanaged page %p is queued", m)); } VM_CNT_INC(v_tfree); if (vm_page_sbusied(m)) panic("vm_page_free_prep: freeing shared busy page %p", m); if (m->object != NULL) { vm_page_object_remove(m); /* * The object reference can be released without an atomic * operation. */ KASSERT((m->flags & PG_FICTITIOUS) != 0 || m->ref_count == VPRC_OBJREF, ("vm_page_free_prep: page %p has unexpected ref_count %u", m, m->ref_count)); m->object = NULL; m->ref_count -= VPRC_OBJREF; } if (vm_page_xbusied(m)) vm_page_xunbusy(m); /* * If fictitious remove object association and * return. */ if ((m->flags & PG_FICTITIOUS) != 0) { KASSERT(m->ref_count == 1, ("fictitious page %p is referenced", m)); KASSERT(m->queue == PQ_NONE, ("fictitious page %p is queued", m)); return (false); } /* * Pages need not be dequeued before they are returned to the physical * memory allocator, but they must at least be marked for a deferred * dequeue. */ if ((m->oflags & VPO_UNMANAGED) == 0) vm_page_dequeue_deferred_free(m); m->valid = 0; vm_page_undirty(m); if (m->ref_count != 0) panic("vm_page_free_prep: page %p has references", m); /* * Restore the default memory attribute to the page. */ if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); #if VM_NRESERVLEVEL > 0 /* * Determine whether the page belongs to a reservation. If the page was * allocated from a per-CPU cache, it cannot belong to a reservation, so * as an optimization, we avoid the check in that case. */ if ((m->flags & PG_PCPU_CACHE) == 0 && vm_reserv_free_page(m)) return (false); #endif return (true); } /* * vm_page_free_toq: * * Returns the given page to the free list, disassociating it * from any VM object. * * The object must be locked. The page must be locked if it is * managed. */ void vm_page_free_toq(vm_page_t m) { struct vm_domain *vmd; uma_zone_t zone; if (!vm_page_free_prep(m)) return; vmd = vm_pagequeue_domain(m); zone = vmd->vmd_pgcache[m->pool].zone; if ((m->flags & PG_PCPU_CACHE) != 0 && zone != NULL) { uma_zfree(zone, m); return; } vm_domain_free_lock(vmd); vm_phys_free_pages(m, 0); vm_domain_free_unlock(vmd); vm_domain_freecnt_inc(vmd, 1); } /* * vm_page_free_pages_toq: * * Returns a list of pages to the free list, disassociating it * from any VM object. In other words, this is equivalent to * calling vm_page_free_toq() for each page of a list of VM objects. * * The objects must be locked. The pages must be locked if it is * managed. */ void vm_page_free_pages_toq(struct spglist *free, bool update_wire_count) { vm_page_t m; int count; if (SLIST_EMPTY(free)) return; count = 0; while ((m = SLIST_FIRST(free)) != NULL) { count++; SLIST_REMOVE_HEAD(free, plinks.s.ss); vm_page_free_toq(m); } if (update_wire_count) vm_wire_sub(count); } /* * Mark this page as wired down, preventing reclamation by the page daemon * or when the containing object is destroyed. */ void vm_page_wire(vm_page_t m) { u_int old; KASSERT(m->object != NULL, ("vm_page_wire: page %p does not belong to an object", m)); if (!vm_page_busied(m)) VM_OBJECT_ASSERT_LOCKED(m->object); KASSERT((m->flags & PG_FICTITIOUS) == 0 || VPRC_WIRE_COUNT(m->ref_count) >= 1, ("vm_page_wire: fictitious page %p has zero wirings", m)); old = atomic_fetchadd_int(&m->ref_count, 1); KASSERT(VPRC_WIRE_COUNT(old) != VPRC_WIRE_COUNT_MAX, ("vm_page_wire: counter overflow for page %p", m)); if (VPRC_WIRE_COUNT(old) == 0) vm_wire_add(1); } /* * Attempt to wire a mapped page following a pmap lookup of that page. * This may fail if a thread is concurrently tearing down mappings of the page. * The transient failure is acceptable because it translates to the * failure of the caller pmap_extract_and_hold(), which should be then * followed by the vm_fault() fallback, see e.g. vm_fault_quick_hold_pages(). */ bool vm_page_wire_mapped(vm_page_t m) { u_int old; old = m->ref_count; do { KASSERT(old > 0, ("vm_page_wire_mapped: wiring unreferenced page %p", m)); if ((old & VPRC_BLOCKED) != 0) return (false); } while (!atomic_fcmpset_int(&m->ref_count, &old, old + 1)); if (VPRC_WIRE_COUNT(old) == 0) vm_wire_add(1); return (true); } /* * Release one wiring of the specified page, potentially allowing it to be * paged out. * * Only managed pages belonging to an object can be paged out. If the number * of wirings transitions to zero and the page is eligible for page out, then * the page is added to the specified paging queue. If the released wiring * represented the last reference to the page, the page is freed. * * A managed page must be locked. */ void vm_page_unwire(vm_page_t m, uint8_t queue) { u_int old; bool locked; KASSERT(queue < PQ_COUNT, ("vm_page_unwire: invalid queue %u request for page %p", queue, m)); if ((m->oflags & VPO_UNMANAGED) != 0) { if (vm_page_unwire_noq(m) && m->ref_count == 0) vm_page_free(m); return; } /* * Update LRU state before releasing the wiring reference. * We only need to do this once since we hold the page lock. * Use a release store when updating the reference count to * synchronize with vm_page_free_prep(). */ old = m->ref_count; locked = false; do { KASSERT(VPRC_WIRE_COUNT(old) > 0, ("vm_page_unwire: wire count underflow for page %p", m)); if (!locked && VPRC_WIRE_COUNT(old) == 1) { vm_page_lock(m); locked = true; if (queue == PQ_ACTIVE && vm_page_queue(m) == PQ_ACTIVE) vm_page_reference(m); else vm_page_mvqueue(m, queue); } } while (!atomic_fcmpset_rel_int(&m->ref_count, &old, old - 1)); /* * Release the lock only after the wiring is released, to ensure that * the page daemon does not encounter and dequeue the page while it is * still wired. */ if (locked) vm_page_unlock(m); if (VPRC_WIRE_COUNT(old) == 1) { vm_wire_sub(1); if (old == 1) vm_page_free(m); } } /* * Unwire a page without (re-)inserting it into a page queue. It is up * to the caller to enqueue, requeue, or free the page as appropriate. * In most cases involving managed pages, vm_page_unwire() should be used * instead. */ bool vm_page_unwire_noq(vm_page_t m) { u_int old; old = vm_page_drop(m, 1); KASSERT(VPRC_WIRE_COUNT(old) != 0, ("vm_page_unref: counter underflow for page %p", m)); KASSERT((m->flags & PG_FICTITIOUS) == 0 || VPRC_WIRE_COUNT(old) > 1, ("vm_page_unref: missing ref on fictitious page %p", m)); if (VPRC_WIRE_COUNT(old) > 1) return (false); vm_wire_sub(1); return (true); } /* * Ensure that the page is in the specified page queue. If the page is * active or being moved to the active queue, ensure that its act_count is * at least ACT_INIT but do not otherwise mess with it. Otherwise, ensure that * the page is at the tail of its page queue. * * The page may be wired. The caller should release its wiring reference * before releasing the page lock, otherwise the page daemon may immediately * dequeue the page. * * A managed page must be locked. */ static __always_inline void vm_page_mvqueue(vm_page_t m, const uint8_t nqueue) { vm_page_assert_locked(m); KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("vm_page_mvqueue: page %p is unmanaged", m)); KASSERT(m->ref_count > 0, ("%s: page %p does not carry any references", __func__, m)); if (vm_page_queue(m) != nqueue) { vm_page_dequeue(m); vm_page_enqueue(m, nqueue); } else if (nqueue != PQ_ACTIVE) { vm_page_requeue(m); } if (nqueue == PQ_ACTIVE && m->act_count < ACT_INIT) m->act_count = ACT_INIT; } /* * Put the specified page on the active list (if appropriate). */ void vm_page_activate(vm_page_t m) { if ((m->oflags & VPO_UNMANAGED) != 0 || vm_page_wired(m)) return; vm_page_mvqueue(m, PQ_ACTIVE); } /* * Move the specified page to the tail of the inactive queue, or requeue * the page if it is already in the inactive queue. */ void vm_page_deactivate(vm_page_t m) { if ((m->oflags & VPO_UNMANAGED) != 0 || vm_page_wired(m)) return; vm_page_mvqueue(m, PQ_INACTIVE); } /* * Move the specified page close to the head of the inactive queue, * bypassing LRU. A marker page is used to maintain FIFO ordering. * As with regular enqueues, we use a per-CPU batch queue to reduce * contention on the page queue lock. */ static void _vm_page_deactivate_noreuse(vm_page_t m) { vm_page_assert_locked(m); if (!vm_page_inactive(m)) { vm_page_dequeue(m); m->queue = PQ_INACTIVE; } if ((m->aflags & PGA_REQUEUE_HEAD) == 0) vm_page_aflag_set(m, PGA_REQUEUE_HEAD); vm_page_pqbatch_submit(m, PQ_INACTIVE); } void vm_page_deactivate_noreuse(vm_page_t m) { KASSERT(m->object != NULL, ("vm_page_deactivate_noreuse: page %p has no object", m)); if ((m->oflags & VPO_UNMANAGED) == 0 && !vm_page_wired(m)) _vm_page_deactivate_noreuse(m); } /* * Put a page in the laundry, or requeue it if it is already there. */ void vm_page_launder(vm_page_t m) { if ((m->oflags & VPO_UNMANAGED) != 0 || vm_page_wired(m)) return; vm_page_mvqueue(m, PQ_LAUNDRY); } /* * Put a page in the PQ_UNSWAPPABLE holding queue. */ void vm_page_unswappable(vm_page_t m) { vm_page_assert_locked(m); KASSERT(!vm_page_wired(m) && (m->oflags & VPO_UNMANAGED) == 0, ("page %p already unswappable", m)); vm_page_dequeue(m); vm_page_enqueue(m, PQ_UNSWAPPABLE); } static void vm_page_release_toq(vm_page_t m, int flags) { vm_page_assert_locked(m); /* * Use a check of the valid bits to determine whether we should * accelerate reclamation of the page. The object lock might not be * held here, in which case the check is racy. At worst we will either * accelerate reclamation of a valid page and violate LRU, or * unnecessarily defer reclamation of an invalid page. * * If we were asked to not cache the page, place it near the head of the * inactive queue so that is reclaimed sooner. */ if ((flags & (VPR_TRYFREE | VPR_NOREUSE)) != 0 || m->valid == 0) _vm_page_deactivate_noreuse(m); else if (vm_page_active(m)) vm_page_reference(m); else vm_page_mvqueue(m, PQ_INACTIVE); } /* * Unwire a page and either attempt to free it or re-add it to the page queues. */ void vm_page_release(vm_page_t m, int flags) { vm_object_t object; u_int old; bool locked; KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("vm_page_release: page %p is unmanaged", m)); if ((flags & VPR_TRYFREE) != 0) { for (;;) { object = (vm_object_t)atomic_load_ptr(&m->object); if (object == NULL) break; /* Depends on type-stability. */ if (vm_page_busied(m) || !VM_OBJECT_TRYWLOCK(object)) { object = NULL; break; } if (object == m->object) break; VM_OBJECT_WUNLOCK(object); } if (__predict_true(object != NULL)) { vm_page_release_locked(m, flags); VM_OBJECT_WUNLOCK(object); return; } } /* * Update LRU state before releasing the wiring reference. * Use a release store when updating the reference count to * synchronize with vm_page_free_prep(). */ old = m->ref_count; locked = false; do { KASSERT(VPRC_WIRE_COUNT(old) > 0, ("vm_page_unwire: wire count underflow for page %p", m)); if (!locked && VPRC_WIRE_COUNT(old) == 1) { vm_page_lock(m); locked = true; vm_page_release_toq(m, flags); } } while (!atomic_fcmpset_rel_int(&m->ref_count, &old, old - 1)); /* * Release the lock only after the wiring is released, to ensure that * the page daemon does not encounter and dequeue the page while it is * still wired. */ if (locked) vm_page_unlock(m); if (VPRC_WIRE_COUNT(old) == 1) { vm_wire_sub(1); if (old == 1) vm_page_free(m); } } /* See vm_page_release(). */ void vm_page_release_locked(vm_page_t m, int flags) { VM_OBJECT_ASSERT_WLOCKED(m->object); KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("vm_page_release_locked: page %p is unmanaged", m)); if (vm_page_unwire_noq(m)) { if ((flags & VPR_TRYFREE) != 0 && (m->object->ref_count == 0 || !pmap_page_is_mapped(m)) && m->dirty == 0 && !vm_page_busied(m)) { vm_page_free(m); } else { vm_page_lock(m); vm_page_release_toq(m, flags); vm_page_unlock(m); } } } static bool vm_page_try_blocked_op(vm_page_t m, void (*op)(vm_page_t)) { u_int old; KASSERT(m->object != NULL && (m->oflags & VPO_UNMANAGED) == 0, ("vm_page_try_blocked_op: page %p has no object", m)); KASSERT(vm_page_busied(m), ("vm_page_try_blocked_op: page %p is not busy", m)); VM_OBJECT_ASSERT_LOCKED(m->object); old = m->ref_count; do { KASSERT(old != 0, ("vm_page_try_blocked_op: page %p has no references", m)); if (VPRC_WIRE_COUNT(old) != 0) return (false); } while (!atomic_fcmpset_int(&m->ref_count, &old, old | VPRC_BLOCKED)); (op)(m); /* * If the object is read-locked, new wirings may be created via an * object lookup. */ old = vm_page_drop(m, VPRC_BLOCKED); KASSERT(!VM_OBJECT_WOWNED(m->object) || old == (VPRC_BLOCKED | VPRC_OBJREF), ("vm_page_try_blocked_op: unexpected refcount value %u for %p", old, m)); return (true); } /* * Atomically check for wirings and remove all mappings of the page. */ bool vm_page_try_remove_all(vm_page_t m) { return (vm_page_try_blocked_op(m, pmap_remove_all)); } /* * Atomically check for wirings and remove all writeable mappings of the page. */ bool vm_page_try_remove_write(vm_page_t m) { return (vm_page_try_blocked_op(m, pmap_remove_write)); } /* * vm_page_advise * * Apply the specified advice to the given page. * * The object and page must be locked. */ void vm_page_advise(vm_page_t m, int advice) { vm_page_assert_locked(m); VM_OBJECT_ASSERT_WLOCKED(m->object); if (advice == MADV_FREE) /* * Mark the page clean. This will allow the page to be freed * without first paging it out. MADV_FREE pages are often * quickly reused by malloc(3), so we do not do anything that * would result in a page fault on a later access. */ vm_page_undirty(m); else if (advice != MADV_DONTNEED) { if (advice == MADV_WILLNEED) vm_page_activate(m); return; } /* * Clear any references to the page. Otherwise, the page daemon will * immediately reactivate the page. */ vm_page_aflag_clear(m, PGA_REFERENCED); if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m)) vm_page_dirty(m); /* * Place clean pages near the head of the inactive queue rather than * the tail, thus defeating the queue's LRU operation and ensuring that * the page will be reused quickly. Dirty pages not already in the * laundry are moved there. */ if (m->dirty == 0) vm_page_deactivate_noreuse(m); else if (!vm_page_in_laundry(m)) vm_page_launder(m); } /* * Grab a page, waiting until we are waken up due to the page * changing state. We keep on waiting, if the page continues * to be in the object. If the page doesn't exist, first allocate it * and then conditionally zero it. * * This routine may sleep. * * The object must be locked on entry. The lock will, however, be released * and reacquired if the routine sleeps. */ vm_page_t vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) { vm_page_t m; int sleep; int pflags; VM_OBJECT_ASSERT_WLOCKED(object); KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || (allocflags & VM_ALLOC_IGN_SBUSY) != 0, ("vm_page_grab: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); pflags = allocflags & ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL | VM_ALLOC_NOBUSY); if ((allocflags & VM_ALLOC_NOWAIT) == 0) pflags |= VM_ALLOC_WAITFAIL; if ((allocflags & VM_ALLOC_IGN_SBUSY) != 0) pflags |= VM_ALLOC_SBUSY; retrylookup: if ((m = vm_page_lookup(object, pindex)) != NULL) { if ((allocflags & (VM_ALLOC_IGN_SBUSY | VM_ALLOC_SBUSY)) != 0) sleep = !vm_page_trysbusy(m); else sleep = !vm_page_tryxbusy(m); if (sleep) { if ((allocflags & VM_ALLOC_NOWAIT) != 0) return (NULL); /* * Reference the page before unlocking and * sleeping so that the page daemon is less * likely to reclaim it. */ if ((allocflags & VM_ALLOC_NOCREAT) == 0) vm_page_aflag_set(m, PGA_REFERENCED); vm_page_busy_sleep(m, "pgrbwt", (allocflags & VM_ALLOC_IGN_SBUSY) != 0); VM_OBJECT_WLOCK(object); if ((allocflags & VM_ALLOC_WAITFAIL) != 0) return (NULL); goto retrylookup; } else { if ((allocflags & VM_ALLOC_WIRED) != 0) vm_page_wire(m); goto out; } } if ((allocflags & VM_ALLOC_NOCREAT) != 0) return (NULL); m = vm_page_alloc(object, pindex, pflags); if (m == NULL) { if ((allocflags & VM_ALLOC_NOWAIT) != 0) return (NULL); goto retrylookup; } if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0) pmap_zero_page(m); out: if ((allocflags & VM_ALLOC_NOBUSY) != 0) { if ((allocflags & VM_ALLOC_IGN_SBUSY) != 0) vm_page_sunbusy(m); else vm_page_xunbusy(m); } return (m); } /* * Grab a page and make it valid, paging in if necessary. Pages missing from * their pager are zero filled and validated. */ int vm_page_grab_valid(vm_page_t *mp, vm_object_t object, vm_pindex_t pindex, int allocflags) { vm_page_t m; bool sleep, xbusy; int pflags; int rv; KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || (allocflags & VM_ALLOC_IGN_SBUSY) != 0, ("vm_page_grab_valid: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); KASSERT((allocflags & (VM_ALLOC_NOWAIT | VM_ALLOC_WAITFAIL | VM_ALLOC_ZERO)) == 0, ("vm_page_grab_valid: Invalid flags 0x%X", allocflags)); VM_OBJECT_ASSERT_WLOCKED(object); pflags = allocflags & ~(VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY); pflags |= VM_ALLOC_WAITFAIL; retrylookup: xbusy = false; if ((m = vm_page_lookup(object, pindex)) != NULL) { /* * If the page is fully valid it can only become invalid * with the object lock held. If it is not valid it can * become valid with the busy lock held. Therefore, we * may unnecessarily lock the exclusive busy here if we * race with I/O completion not using the object lock. * However, we will not end up with an invalid page and a * shared lock. */ if (!vm_page_all_valid(m) || (allocflags & (VM_ALLOC_IGN_SBUSY | VM_ALLOC_SBUSY)) == 0) { sleep = !vm_page_tryxbusy(m); xbusy = true; } else sleep = !vm_page_trysbusy(m); if (sleep) { /* * Reference the page before unlocking and * sleeping so that the page daemon is less * likely to reclaim it. */ if ((allocflags & VM_ALLOC_NOCREAT) == 0) vm_page_aflag_set(m, PGA_REFERENCED); vm_page_busy_sleep(m, "pgrbwt", (allocflags & VM_ALLOC_IGN_SBUSY) != 0); VM_OBJECT_WLOCK(object); goto retrylookup; } if ((allocflags & VM_ALLOC_NOCREAT) != 0 && !vm_page_all_valid(m)) { if (xbusy) vm_page_xunbusy(m); else vm_page_sunbusy(m); *mp = NULL; return (VM_PAGER_FAIL); } if ((allocflags & VM_ALLOC_WIRED) != 0) vm_page_wire(m); if (vm_page_all_valid(m)) goto out; } else if ((allocflags & VM_ALLOC_NOCREAT) != 0) { *mp = NULL; return (VM_PAGER_FAIL); } else if ((m = vm_page_alloc(object, pindex, pflags)) != NULL) { xbusy = true; } else { goto retrylookup; } vm_page_assert_xbusied(m); MPASS(xbusy); if (vm_pager_has_page(object, pindex, NULL, NULL)) { rv = vm_pager_get_pages(object, &m, 1, NULL, NULL); if (rv != VM_PAGER_OK) { if (allocflags & VM_ALLOC_WIRED) vm_page_unwire_noq(m); vm_page_free(m); *mp = NULL; return (rv); } MPASS(vm_page_all_valid(m)); } else { vm_page_zero_invalid(m, TRUE); } out: if ((allocflags & VM_ALLOC_NOBUSY) != 0) { if (xbusy) vm_page_xunbusy(m); else vm_page_sunbusy(m); } if ((allocflags & VM_ALLOC_SBUSY) != 0 && xbusy) vm_page_busy_downgrade(m); *mp = m; return (VM_PAGER_OK); } /* * Return the specified range of pages from the given object. For each * page offset within the range, if a page already exists within the object * at that offset and it is busy, then wait for it to change state. If, * instead, the page doesn't exist, then allocate it. * * The caller must always specify an allocation class. * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs the pages * * The caller must always specify that the pages are to be busied and/or * wired. * * optional allocation flags: * VM_ALLOC_IGN_SBUSY do not sleep on soft busy pages * VM_ALLOC_NOBUSY do not exclusive busy the page * VM_ALLOC_NOWAIT do not sleep * VM_ALLOC_SBUSY set page to sbusy state * VM_ALLOC_WIRED wire the pages * VM_ALLOC_ZERO zero and validate any invalid pages * * If VM_ALLOC_NOWAIT is not specified, this routine may sleep. Otherwise, it * may return a partial prefix of the requested range. */ int vm_page_grab_pages(vm_object_t object, vm_pindex_t pindex, int allocflags, vm_page_t *ma, int count) { vm_page_t m, mpred; int pflags; int i; bool sleep; VM_OBJECT_ASSERT_WLOCKED(object); KASSERT(((u_int)allocflags >> VM_ALLOC_COUNT_SHIFT) == 0, ("vm_page_grap_pages: VM_ALLOC_COUNT() is not allowed")); KASSERT((allocflags & VM_ALLOC_NOBUSY) == 0 || (allocflags & VM_ALLOC_WIRED) != 0, ("vm_page_grab_pages: the pages must be busied or wired")); KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || (allocflags & VM_ALLOC_IGN_SBUSY) != 0, ("vm_page_grab_pages: VM_ALLOC_SBUSY/IGN_SBUSY mismatch")); if (count == 0) return (0); pflags = allocflags & ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL | VM_ALLOC_NOBUSY); if ((allocflags & VM_ALLOC_NOWAIT) == 0) pflags |= VM_ALLOC_WAITFAIL; if ((allocflags & VM_ALLOC_IGN_SBUSY) != 0) pflags |= VM_ALLOC_SBUSY; i = 0; retrylookup: m = vm_radix_lookup_le(&object->rtree, pindex + i); if (m == NULL || m->pindex != pindex + i) { mpred = m; m = NULL; } else mpred = TAILQ_PREV(m, pglist, listq); for (; i < count; i++) { if (m != NULL) { if ((allocflags & (VM_ALLOC_SBUSY | VM_ALLOC_IGN_SBUSY)) != 0) sleep = !vm_page_trysbusy(m); else sleep = !vm_page_tryxbusy(m); if (sleep) { if ((allocflags & VM_ALLOC_NOWAIT) != 0) break; /* * Reference the page before unlocking and * sleeping so that the page daemon is less * likely to reclaim it. */ if ((allocflags & VM_ALLOC_NOCREAT) == 0) vm_page_aflag_set(m, PGA_REFERENCED); vm_page_busy_sleep(m, "grbmaw", (allocflags & VM_ALLOC_IGN_SBUSY) != 0); VM_OBJECT_WLOCK(object); goto retrylookup; } if ((allocflags & VM_ALLOC_WIRED) != 0) vm_page_wire(m); } else { if ((allocflags & VM_ALLOC_NOCREAT) != 0) break; m = vm_page_alloc_after(object, pindex + i, pflags | VM_ALLOC_COUNT(count - i), mpred); if (m == NULL) { if ((allocflags & VM_ALLOC_NOWAIT) != 0) break; goto retrylookup; } } if (vm_page_none_valid(m) && (allocflags & VM_ALLOC_ZERO) != 0) { if ((m->flags & PG_ZERO) == 0) pmap_zero_page(m); vm_page_valid(m); } if ((allocflags & VM_ALLOC_NOBUSY) != 0) { if ((allocflags & VM_ALLOC_IGN_SBUSY) != 0) vm_page_sunbusy(m); else vm_page_xunbusy(m); } ma[i] = mpred = m; m = vm_page_next(m); } return (i); } /* * Mapping function for valid or dirty bits in a page. * * Inputs are required to range within a page. */ vm_page_bits_t vm_page_bits(int base, int size) { int first_bit; int last_bit; KASSERT( base + size <= PAGE_SIZE, ("vm_page_bits: illegal base/size %d/%d", base, size) ); if (size == 0) /* handle degenerate case */ return (0); first_bit = base >> DEV_BSHIFT; last_bit = (base + size - 1) >> DEV_BSHIFT; return (((vm_page_bits_t)2 << last_bit) - ((vm_page_bits_t)1 << first_bit)); } void vm_page_bits_set(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t set) { #if PAGE_SIZE == 32768 atomic_set_64((uint64_t *)bits, set); #elif PAGE_SIZE == 16384 atomic_set_32((uint32_t *)bits, set); #elif (PAGE_SIZE == 8192) && defined(atomic_set_16) atomic_set_16((uint16_t *)bits, set); #elif (PAGE_SIZE == 4096) && defined(atomic_set_8) atomic_set_8((uint8_t *)bits, set); #else /* PAGE_SIZE <= 8192 */ uintptr_t addr; int shift; addr = (uintptr_t)bits; /* * Use a trick to perform a 32-bit atomic on the * containing aligned word, to not depend on the existence * of atomic_{set, clear}_{8, 16}. */ shift = addr & (sizeof(uint32_t) - 1); #if BYTE_ORDER == BIG_ENDIAN shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY; #else shift *= NBBY; #endif addr &= ~(sizeof(uint32_t) - 1); atomic_set_32((uint32_t *)addr, set << shift); #endif /* PAGE_SIZE */ } static inline void vm_page_bits_clear(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t clear) { #if PAGE_SIZE == 32768 atomic_clear_64((uint64_t *)bits, clear); #elif PAGE_SIZE == 16384 atomic_clear_32((uint32_t *)bits, clear); #elif (PAGE_SIZE == 8192) && defined(atomic_clear_16) atomic_clear_16((uint16_t *)bits, clear); #elif (PAGE_SIZE == 4096) && defined(atomic_clear_8) atomic_clear_8((uint8_t *)bits, clear); #else /* PAGE_SIZE <= 8192 */ uintptr_t addr; int shift; addr = (uintptr_t)bits; /* * Use a trick to perform a 32-bit atomic on the * containing aligned word, to not depend on the existence * of atomic_{set, clear}_{8, 16}. */ shift = addr & (sizeof(uint32_t) - 1); #if BYTE_ORDER == BIG_ENDIAN shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY; #else shift *= NBBY; #endif addr &= ~(sizeof(uint32_t) - 1); atomic_clear_32((uint32_t *)addr, clear << shift); #endif /* PAGE_SIZE */ } /* * vm_page_set_valid_range: * * Sets portions of a page valid. The arguments are expected * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive * of any partial chunks touched by the range. The invalid portion of * such chunks will be zeroed. * * (base + size) must be less then or equal to PAGE_SIZE. */ void vm_page_set_valid_range(vm_page_t m, int base, int size) { int endoff, frag; vm_page_bits_t pagebits; vm_page_assert_busied(m); if (size == 0) /* handle degenerate case */ return; /* * If the base is not DEV_BSIZE aligned and the valid * bit is clear, we have to zero out a portion of the * first block. */ if ((frag = rounddown2(base, DEV_BSIZE)) != base && (m->valid & (1 << (base >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, frag, base - frag); /* * If the ending offset is not DEV_BSIZE aligned and the * valid bit is clear, we have to zero out a portion of * the last block. */ endoff = base + size; if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, endoff, DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); /* * Assert that no previously invalid block that is now being validated * is already dirty. */ KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0, ("vm_page_set_valid_range: page %p is dirty", m)); /* * Set valid bits inclusive of any overlap. */ pagebits = vm_page_bits(base, size); if (vm_page_xbusied(m)) m->valid |= pagebits; else vm_page_bits_set(m, &m->valid, pagebits); } /* * Clear the given bits from the specified page's dirty field. */ static __inline void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits) { vm_page_assert_busied(m); /* * If the page is xbusied and not write mapped we are the * only thread that can modify dirty bits. Otherwise, The pmap * layer can call vm_page_dirty() without holding a distinguished * lock. The combination of page busy and atomic operations * suffice to guarantee consistency of the page dirty field. */ if (vm_page_xbusied(m) && !pmap_page_is_write_mapped(m)) m->dirty &= ~pagebits; else vm_page_bits_clear(m, &m->dirty, pagebits); } /* * vm_page_set_validclean: * * Sets portions of a page valid and clean. The arguments are expected * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive * of any partial chunks touched by the range. The invalid portion of * such chunks will be zero'd. * * (base + size) must be less then or equal to PAGE_SIZE. */ void vm_page_set_validclean(vm_page_t m, int base, int size) { vm_page_bits_t oldvalid, pagebits; int endoff, frag; vm_page_assert_busied(m); if (size == 0) /* handle degenerate case */ return; /* * If the base is not DEV_BSIZE aligned and the valid * bit is clear, we have to zero out a portion of the * first block. */ if ((frag = rounddown2(base, DEV_BSIZE)) != base && (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, frag, base - frag); /* * If the ending offset is not DEV_BSIZE aligned and the * valid bit is clear, we have to zero out a portion of * the last block. */ endoff = base + size; if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, endoff, DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); /* * Set valid, clear dirty bits. If validating the entire * page we can safely clear the pmap modify bit. We also * use this opportunity to clear the PGA_NOSYNC flag. If a process * takes a write fault on a MAP_NOSYNC memory area the flag will * be set again. * * We set valid bits inclusive of any overlap, but we can only * clear dirty bits for DEV_BSIZE chunks that are fully within * the range. */ oldvalid = m->valid; pagebits = vm_page_bits(base, size); if (vm_page_xbusied(m)) m->valid |= pagebits; else vm_page_bits_set(m, &m->valid, pagebits); #if 0 /* NOT YET */ if ((frag = base & (DEV_BSIZE - 1)) != 0) { frag = DEV_BSIZE - frag; base += frag; size -= frag; if (size < 0) size = 0; } pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1)); #endif if (base == 0 && size == PAGE_SIZE) { /* * The page can only be modified within the pmap if it is * mapped, and it can only be mapped if it was previously * fully valid. */ if (oldvalid == VM_PAGE_BITS_ALL) /* * Perform the pmap_clear_modify() first. Otherwise, * a concurrent pmap operation, such as * pmap_protect(), could clear a modification in the * pmap and set the dirty field on the page before * pmap_clear_modify() had begun and after the dirty * field was cleared here. */ pmap_clear_modify(m); m->dirty = 0; vm_page_aflag_clear(m, PGA_NOSYNC); } else if (oldvalid != VM_PAGE_BITS_ALL && vm_page_xbusied(m)) m->dirty &= ~pagebits; else vm_page_clear_dirty_mask(m, pagebits); } void vm_page_clear_dirty(vm_page_t m, int base, int size) { vm_page_clear_dirty_mask(m, vm_page_bits(base, size)); } /* * vm_page_set_invalid: * * Invalidates DEV_BSIZE'd chunks within a page. Both the * valid and dirty bits for the effected areas are cleared. */ void vm_page_set_invalid(vm_page_t m, int base, int size) { vm_page_bits_t bits; vm_object_t object; /* * The object lock is required so that pages can't be mapped * read-only while we're in the process of invalidating them. */ object = m->object; VM_OBJECT_ASSERT_WLOCKED(object); vm_page_assert_busied(m); if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) + size >= object->un_pager.vnp.vnp_size) bits = VM_PAGE_BITS_ALL; else bits = vm_page_bits(base, size); if (object->ref_count != 0 && vm_page_all_valid(m) && bits != 0) pmap_remove_all(m); KASSERT((bits == 0 && vm_page_all_valid(m)) || !pmap_page_is_mapped(m), ("vm_page_set_invalid: page %p is mapped", m)); if (vm_page_xbusied(m)) { m->valid &= ~bits; m->dirty &= ~bits; } else { vm_page_bits_clear(m, &m->valid, bits); vm_page_bits_clear(m, &m->dirty, bits); } } /* * vm_page_invalid: * * Invalidates the entire page. The page must be busy, unmapped, and * the enclosing object must be locked. The object locks protects * against concurrent read-only pmap enter which is done without * busy. */ void vm_page_invalid(vm_page_t m) { vm_page_assert_busied(m); VM_OBJECT_ASSERT_LOCKED(m->object); MPASS(!pmap_page_is_mapped(m)); if (vm_page_xbusied(m)) m->valid = 0; else vm_page_bits_clear(m, &m->valid, VM_PAGE_BITS_ALL); } /* * vm_page_zero_invalid() * * The kernel assumes that the invalid portions of a page contain * garbage, but such pages can be mapped into memory by user code. * When this occurs, we must zero out the non-valid portions of the * page so user code sees what it expects. * * Pages are most often semi-valid when the end of a file is mapped * into memory and the file's size is not page aligned. */ void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid) { int b; int i; /* * Scan the valid bits looking for invalid sections that * must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the * valid bit may be set ) have already been zeroed by * vm_page_set_validclean(). */ for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) { if (i == (PAGE_SIZE / DEV_BSIZE) || (m->valid & ((vm_page_bits_t)1 << i))) { if (i > b) { pmap_zero_page_area(m, b << DEV_BSHIFT, (i - b) << DEV_BSHIFT); } b = i + 1; } } /* * setvalid is TRUE when we can safely set the zero'd areas * as being valid. We can do this if there are no cache consistancy * issues. e.g. it is ok to do with UFS, but not ok to do with NFS. */ if (setvalid) vm_page_valid(m); } /* * vm_page_is_valid: * * Is (partial) page valid? Note that the case where size == 0 * will return FALSE in the degenerate case where the page is * entirely invalid, and TRUE otherwise. * * Some callers envoke this routine without the busy lock held and * handle races via higher level locks. Typical callers should * hold a busy lock to prevent invalidation. */ int vm_page_is_valid(vm_page_t m, int base, int size) { vm_page_bits_t bits; bits = vm_page_bits(base, size); return (m->valid != 0 && (m->valid & bits) == bits); } /* * Returns true if all of the specified predicates are true for the entire * (super)page and false otherwise. */ bool vm_page_ps_test(vm_page_t m, int flags, vm_page_t skip_m) { vm_object_t object; int i, npages; object = m->object; if (skip_m != NULL && skip_m->object != object) return (false); VM_OBJECT_ASSERT_LOCKED(object); npages = atop(pagesizes[m->psind]); /* * The physically contiguous pages that make up a superpage, i.e., a * page with a page size index ("psind") greater than zero, will * occupy adjacent entries in vm_page_array[]. */ for (i = 0; i < npages; i++) { /* Always test object consistency, including "skip_m". */ if (m[i].object != object) return (false); if (&m[i] == skip_m) continue; if ((flags & PS_NONE_BUSY) != 0 && vm_page_busied(&m[i])) return (false); if ((flags & PS_ALL_DIRTY) != 0) { /* * Calling vm_page_test_dirty() or pmap_is_modified() * might stop this case from spuriously returning * "false". However, that would require a write lock * on the object containing "m[i]". */ if (m[i].dirty != VM_PAGE_BITS_ALL) return (false); } if ((flags & PS_ALL_VALID) != 0 && m[i].valid != VM_PAGE_BITS_ALL) return (false); } return (true); } /* * Set the page's dirty bits if the page is modified. */ void vm_page_test_dirty(vm_page_t m) { vm_page_assert_busied(m); if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m)) vm_page_dirty(m); } void vm_page_valid(vm_page_t m) { vm_page_assert_busied(m); if (vm_page_xbusied(m)) m->valid = VM_PAGE_BITS_ALL; else vm_page_bits_set(m, &m->valid, VM_PAGE_BITS_ALL); } void vm_page_lock_KBI(vm_page_t m, const char *file, int line) { mtx_lock_flags_(vm_page_lockptr(m), 0, file, line); } void vm_page_unlock_KBI(vm_page_t m, const char *file, int line) { mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line); } int vm_page_trylock_KBI(vm_page_t m, const char *file, int line) { return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line)); } #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) void vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line) { vm_page_lock_assert_KBI(m, MA_OWNED, file, line); } void vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line) { mtx_assert_(vm_page_lockptr(m), a, file, line); } #endif #ifdef INVARIANTS void vm_page_object_busy_assert(vm_page_t m) { /* * Certain of the page's fields may only be modified by the * holder of a page or object busy. */ if (m->object != NULL && !vm_page_busied(m)) VM_OBJECT_ASSERT_BUSY(m->object); } void vm_page_assert_pga_writeable(vm_page_t m, uint16_t bits) { if ((bits & PGA_WRITEABLE) == 0) return; /* * The PGA_WRITEABLE flag can only be set if the page is * managed, is exclusively busied or the object is locked. * Currently, this flag is only set by pmap_enter(). */ KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("PGA_WRITEABLE on unmanaged page")); if (!vm_page_xbusied(m)) VM_OBJECT_ASSERT_BUSY(m->object); } #endif #include "opt_ddb.h" #ifdef DDB #include #include DB_SHOW_COMMAND(page, vm_page_print_page_info) { db_printf("vm_cnt.v_free_count: %d\n", vm_free_count()); db_printf("vm_cnt.v_inactive_count: %d\n", vm_inactive_count()); db_printf("vm_cnt.v_active_count: %d\n", vm_active_count()); db_printf("vm_cnt.v_laundry_count: %d\n", vm_laundry_count()); db_printf("vm_cnt.v_wire_count: %d\n", vm_wire_count()); db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved); db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min); db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target); db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target); } DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info) { int dom; db_printf("pq_free %d\n", vm_free_count()); for (dom = 0; dom < vm_ndomains; dom++) { db_printf( "dom %d page_cnt %d free %d pq_act %d pq_inact %d pq_laund %d pq_unsw %d\n", dom, vm_dom[dom].vmd_page_count, vm_dom[dom].vmd_free_count, vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt, vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt, vm_dom[dom].vmd_pagequeues[PQ_LAUNDRY].pq_cnt, vm_dom[dom].vmd_pagequeues[PQ_UNSWAPPABLE].pq_cnt); } } DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo) { vm_page_t m; boolean_t phys, virt; if (!have_addr) { db_printf("show pginfo addr\n"); return; } phys = strchr(modif, 'p') != NULL; virt = strchr(modif, 'v') != NULL; if (virt) m = PHYS_TO_VM_PAGE(pmap_kextract(addr)); else if (phys) m = PHYS_TO_VM_PAGE(addr); else m = (vm_page_t)addr; db_printf( "page %p obj %p pidx 0x%jx phys 0x%jx q %d ref %u\n" " af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n", m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr, m->queue, m->ref_count, m->aflags, m->oflags, m->flags, m->act_count, m->busy_lock, m->valid, m->dirty); } #endif /* DDB */