diff --git a/sys/vm/uma_core.c b/sys/vm/uma_core.c index 8ac13917a1ef..2c1a725c3d37 100644 --- a/sys/vm/uma_core.c +++ b/sys/vm/uma_core.c @@ -1,5504 +1,5541 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2002-2019 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 #include #include #include #ifdef DEBUG_MEMGUARD #include #endif #include #ifdef INVARIANTS #define UMA_ALWAYS_CTORDTOR 1 #else #define UMA_ALWAYS_CTORDTOR 0 #endif /* * This is the zone and keg from which all zones are spawned. */ static uma_zone_t kegs; static uma_zone_t zones; /* * On INVARIANTS builds, the slab contains a second bitset of the same size, * "dbg_bits", which is laid out immediately after us_free. */ #ifdef INVARIANTS #define SLAB_BITSETS 2 #else #define SLAB_BITSETS 1 #endif /* * These are the two zones from which all offpage uma_slab_ts are allocated. * * One zone is for slab headers that can represent a larger number of items, * making the slabs themselves more efficient, and the other zone is for * headers that are smaller and represent fewer items, making the headers more * efficient. */ #define SLABZONE_SIZE(setsize) \ (sizeof(struct uma_hash_slab) + BITSET_SIZE(setsize) * SLAB_BITSETS) #define SLABZONE0_SETSIZE (PAGE_SIZE / 16) #define SLABZONE1_SETSIZE SLAB_MAX_SETSIZE #define SLABZONE0_SIZE SLABZONE_SIZE(SLABZONE0_SETSIZE) #define SLABZONE1_SIZE SLABZONE_SIZE(SLABZONE1_SETSIZE) static uma_zone_t slabzones[2]; /* * 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"); static MALLOC_DEFINE(M_UMA, "UMA", "UMA Misc"); /* * 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; /* * First available virual address for boot time allocations. */ static vm_offset_t bootstart; static vm_offset_t bootmem; 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. */ 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"); 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, BOOT_KVA, BOOT_PCPU, BOOT_RUNNING, BOOT_SHUTDOWN, } 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; const 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 2 struct uma_bucket_zone bucket_zones[] = { /* Literal bucket sizes. */ { NULL, "2 Bucket", 2, 4096 }, { NULL, "4 Bucket", 4, 3072 }, { NULL, "8 Bucket", 8, 2048 }, { NULL, "16 Bucket", 16, 1024 }, /* Rounded down power of 2 sizes for efficiency. */ { 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.. */ void uma_startup1(vm_offset_t); 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 *contig_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 inline void item_dtor(uma_zone_t zone, void *item, int size, void *udata, enum zfreeskip skip); static int zero_init(void *, int, int); static void zone_free_bucket(uma_zone_t zone, uma_bucket_t bucket, void *udata, int itemdomain, bool ws); static void zone_foreach(void (*zfunc)(uma_zone_t, void *), void *); static void zone_foreach_unlocked(void (*zfunc)(uma_zone_t, void *), void *); static void zone_timeout(uma_zone_t zone, void *); 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_shutdown(void); static void *zone_alloc_item(uma_zone_t, void *, int, int); static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip); static int zone_alloc_limit(uma_zone_t zone, int count, int flags); static void zone_free_limit(uma_zone_t zone, int count); 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); 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(void *, void **, int, int, int); static void zone_release(void *, void **, int); static bool cache_alloc(uma_zone_t, uma_cache_t, void *, int); static bool cache_free(uma_zone_t, uma_cache_t, void *, void *, int); static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS); static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS); static int sysctl_handle_uma_zone_allocs(SYSCTL_HANDLER_ARGS); static int sysctl_handle_uma_zone_frees(SYSCTL_HANDLER_ARGS); static int sysctl_handle_uma_zone_flags(SYSCTL_HANDLER_ARGS); static int sysctl_handle_uma_slab_efficiency(SYSCTL_HANDLER_ARGS); static int sysctl_handle_uma_zone_items(SYSCTL_HANDLER_ARGS); static uint64_t uma_zone_get_allocs(uma_zone_t zone); static SYSCTL_NODE(_vm, OID_AUTO, debug, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "Memory allocation debugging"); #ifdef INVARIANTS static uint64_t uma_keg_get_allocs(uma_keg_t zone); static inline struct noslabbits *slab_dbg_bits(uma_slab_t slab, uma_keg_t keg); 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 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 SYSCTL_NODE(_vm, OID_AUTO, uma, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Universal Memory Allocator"); SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLTYPE_INT, 0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones"); SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLFLAG_MPSAFE|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"); static int multipage_slabs = 1; TUNABLE_INT("vm.debug.uma_multipage_slabs", &multipage_slabs); SYSCTL_INT(_vm_debug, OID_AUTO, uma_multipage_slabs, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &multipage_slabs, 0, "UMA may choose larger slab sizes for better efficiency"); /* * Select the slab zone for an offpage slab with the given maximum item count. */ static inline uma_zone_t slabzone(int ipers) { return (slabzones[ipers > SLABZONE0_SETSIZE]); } /* * This routine checks to see whether or not it's safe to enable buckets. */ static void bucket_enable(void) { KASSERT(booted >= BOOT_KVA, ("Bucket enable before init")); 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_FIRSTTOUCH); } } /* * 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; if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0) /* Count the cross-domain bucket. */ bpcpu++; 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; /* * Don't allocate buckets early in boot. */ if (__predict_false(booted < BOOT_KVA)) 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_ZONE_VM) != 0) flags |= M_NOVM; ubz = bucket_zone_lookup(zone->uz_bucket_size); 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; bucket->ub_seq = SMR_SEQ_INVALID; CTR3(KTR_UMA, "bucket_alloc: zone %s(%p) allocated bucket %p", zone->uz_name, zone, bucket); } return (bucket); } static void bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata) { struct uma_bucket_zone *ubz; if (bucket->ub_cnt != 0) bucket_drain(zone, bucket); KASSERT(bucket->ub_cnt == 0, ("bucket_free: Freeing a non free bucket.")); KASSERT(bucket->ub_seq == SMR_SEQ_INVALID, ("bucket_free: Freeing an SMR 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); } /* * Acquire the domain lock and record contention. */ static uma_zone_domain_t zone_domain_lock(uma_zone_t zone, int domain) { uma_zone_domain_t zdom; bool lockfail; zdom = ZDOM_GET(zone, domain); lockfail = false; if (ZDOM_OWNED(zdom)) lockfail = true; ZDOM_LOCK(zdom); /* This is unsynchronized. The counter does not need to be precise. */ if (lockfail && zone->uz_bucket_size < zone->uz_bucket_size_max) zone->uz_bucket_size++; return (zdom); } /* * Search for the domain with the least cached items and return it if it * is out of balance with the preferred domain. */ static __noinline int zone_domain_lowest(uma_zone_t zone, int pref) { long least, nitems, prefitems; int domain; int i; prefitems = least = LONG_MAX; domain = 0; for (i = 0; i < vm_ndomains; i++) { nitems = ZDOM_GET(zone, i)->uzd_nitems; if (nitems < least) { domain = i; least = nitems; } if (domain == pref) prefitems = nitems; } if (prefitems < least * 2) return (pref); return (domain); } /* * Search for the domain with the most cached items and return it or the * preferred domain if it has enough to proceed. */ static __noinline int zone_domain_highest(uma_zone_t zone, int pref) { long most, nitems; int domain; int i; if (ZDOM_GET(zone, pref)->uzd_nitems > BUCKET_MAX) return (pref); most = 0; domain = 0; for (i = 0; i < vm_ndomains; i++) { nitems = ZDOM_GET(zone, i)->uzd_nitems; if (nitems > most) { domain = i; most = nitems; } } return (domain); } /* * Safely subtract cnt from imax. */ static void zone_domain_imax_sub(uma_zone_domain_t zdom, int cnt) { long new; long old; old = zdom->uzd_imax; do { if (old <= cnt) new = 0; else new = old - cnt; } while (atomic_fcmpset_long(&zdom->uzd_imax, &old, new) == 0); } /* * Set the maximum imax value. */ static void zone_domain_imax_set(uma_zone_domain_t zdom, int nitems) { long old; old = zdom->uzd_imax; do { if (old >= nitems) break; } while (atomic_fcmpset_long(&zdom->uzd_imax, &old, nitems) == 0); } /* * Attempt to satisfy an allocation by retrieving a full bucket from one of the * zone's caches. If a bucket is found the zone is not locked on return. */ static uma_bucket_t zone_fetch_bucket(uma_zone_t zone, uma_zone_domain_t zdom, bool reclaim) { uma_bucket_t bucket; int i; bool dtor = false; ZDOM_LOCK_ASSERT(zdom); if ((bucket = STAILQ_FIRST(&zdom->uzd_buckets)) == NULL) return (NULL); /* SMR Buckets can not be re-used until readers expire. */ if ((zone->uz_flags & UMA_ZONE_SMR) != 0 && bucket->ub_seq != SMR_SEQ_INVALID) { if (!smr_poll(zone->uz_smr, bucket->ub_seq, false)) return (NULL); bucket->ub_seq = SMR_SEQ_INVALID; dtor = (zone->uz_dtor != NULL) || UMA_ALWAYS_CTORDTOR; if (STAILQ_NEXT(bucket, ub_link) != NULL) zdom->uzd_seq = STAILQ_NEXT(bucket, ub_link)->ub_seq; } STAILQ_REMOVE_HEAD(&zdom->uzd_buckets, ub_link); KASSERT(zdom->uzd_nitems >= bucket->ub_cnt, ("%s: item count underflow (%ld, %d)", __func__, zdom->uzd_nitems, bucket->ub_cnt)); KASSERT(bucket->ub_cnt > 0, ("%s: empty bucket in bucket cache", __func__)); zdom->uzd_nitems -= bucket->ub_cnt; /* * Shift the bounds of the current WSS interval to avoid * perturbing the estimate. */ if (reclaim) { zdom->uzd_imin -= lmin(zdom->uzd_imin, bucket->ub_cnt); zone_domain_imax_sub(zdom, bucket->ub_cnt); } else if (zdom->uzd_imin > zdom->uzd_nitems) zdom->uzd_imin = zdom->uzd_nitems; ZDOM_UNLOCK(zdom); if (dtor) for (i = 0; i < bucket->ub_cnt; i++) item_dtor(zone, bucket->ub_bucket[i], zone->uz_size, NULL, SKIP_NONE); 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. The bucket may be freed if it exceeds the bucket limit. */ static void zone_put_bucket(uma_zone_t zone, int domain, uma_bucket_t bucket, void *udata, const bool ws) { uma_zone_domain_t zdom; /* We don't cache empty buckets. This can happen after a reclaim. */ if (bucket->ub_cnt == 0) goto out; zdom = zone_domain_lock(zone, domain); /* * Conditionally set the maximum number of items. */ zdom->uzd_nitems += bucket->ub_cnt; if (__predict_true(zdom->uzd_nitems < zone->uz_bucket_max)) { if (ws) zone_domain_imax_set(zdom, zdom->uzd_nitems); if (STAILQ_EMPTY(&zdom->uzd_buckets)) zdom->uzd_seq = bucket->ub_seq; /* * Try to promote reuse of recently used items. For items * protected by SMR, try to defer reuse to minimize polling. */ if (bucket->ub_seq == SMR_SEQ_INVALID) STAILQ_INSERT_HEAD(&zdom->uzd_buckets, bucket, ub_link); else STAILQ_INSERT_TAIL(&zdom->uzd_buckets, bucket, ub_link); ZDOM_UNLOCK(zdom); return; } zdom->uzd_nitems -= bucket->ub_cnt; ZDOM_UNLOCK(zdom); out: bucket_free(zone, bucket, udata); } /* Pops an item out of a per-cpu cache bucket. */ static inline void * cache_bucket_pop(uma_cache_t cache, uma_cache_bucket_t bucket) { void *item; CRITICAL_ASSERT(curthread); bucket->ucb_cnt--; item = bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt]; #ifdef INVARIANTS bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] = NULL; KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled.")); #endif cache->uc_allocs++; return (item); } /* Pushes an item into a per-cpu cache bucket. */ static inline void cache_bucket_push(uma_cache_t cache, uma_cache_bucket_t bucket, void *item) { CRITICAL_ASSERT(curthread); KASSERT(bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] == NULL, ("uma_zfree: Freeing to non free bucket index.")); bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] = item; bucket->ucb_cnt++; cache->uc_frees++; } /* * Unload a UMA bucket from a per-cpu cache. */ static inline uma_bucket_t cache_bucket_unload(uma_cache_bucket_t bucket) { uma_bucket_t b; b = bucket->ucb_bucket; if (b != NULL) { MPASS(b->ub_entries == bucket->ucb_entries); b->ub_cnt = bucket->ucb_cnt; bucket->ucb_bucket = NULL; bucket->ucb_entries = bucket->ucb_cnt = 0; } return (b); } static inline uma_bucket_t cache_bucket_unload_alloc(uma_cache_t cache) { return (cache_bucket_unload(&cache->uc_allocbucket)); } static inline uma_bucket_t cache_bucket_unload_free(uma_cache_t cache) { return (cache_bucket_unload(&cache->uc_freebucket)); } static inline uma_bucket_t cache_bucket_unload_cross(uma_cache_t cache) { return (cache_bucket_unload(&cache->uc_crossbucket)); } /* * Load a bucket into a per-cpu cache bucket. */ static inline void cache_bucket_load(uma_cache_bucket_t bucket, uma_bucket_t b) { CRITICAL_ASSERT(curthread); MPASS(bucket->ucb_bucket == NULL); MPASS(b->ub_seq == SMR_SEQ_INVALID); bucket->ucb_bucket = b; bucket->ucb_cnt = b->ub_cnt; bucket->ucb_entries = b->ub_entries; } static inline void cache_bucket_load_alloc(uma_cache_t cache, uma_bucket_t b) { cache_bucket_load(&cache->uc_allocbucket, b); } static inline void cache_bucket_load_free(uma_cache_t cache, uma_bucket_t b) { cache_bucket_load(&cache->uc_freebucket, b); } #ifdef NUMA static inline void cache_bucket_load_cross(uma_cache_t cache, uma_bucket_t b) { cache_bucket_load(&cache->uc_crossbucket, b); } #endif /* * Copy and preserve ucb_spare. */ static inline void cache_bucket_copy(uma_cache_bucket_t b1, uma_cache_bucket_t b2) { b1->ucb_bucket = b2->ucb_bucket; b1->ucb_entries = b2->ucb_entries; b1->ucb_cnt = b2->ucb_cnt; } /* * Swap two cache buckets. */ static inline void cache_bucket_swap(uma_cache_bucket_t b1, uma_cache_bucket_t b2) { struct uma_cache_bucket b3; CRITICAL_ASSERT(curthread); cache_bucket_copy(&b3, b1); cache_bucket_copy(b1, b2); cache_bucket_copy(b2, &b3); } /* * Attempt to fetch a bucket from a zone on behalf of the current cpu cache. */ static uma_bucket_t cache_fetch_bucket(uma_zone_t zone, uma_cache_t cache, int domain) { uma_zone_domain_t zdom; uma_bucket_t bucket; /* * Avoid the lock if possible. */ zdom = ZDOM_GET(zone, domain); if (zdom->uzd_nitems == 0) return (NULL); if ((cache_uz_flags(cache) & UMA_ZONE_SMR) != 0 && !smr_poll(zone->uz_smr, zdom->uzd_seq, false)) return (NULL); /* * Check the zone's cache of buckets. */ zdom = zone_domain_lock(zone, domain); if ((bucket = zone_fetch_bucket(zone, zdom, false)) != NULL) return (bucket); ZDOM_UNLOCK(zdom); return (NULL); } 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, NULL); /* 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; ZDOM_LOCK(zdom); 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; ZDOM_UNLOCK(zdom); } /* * 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, void *unused) { uma_keg_t keg; u_int slabs, pages; if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0) goto update_wss; keg = zone->uz_keg; /* * Hash zones are non-numa by definition so the first domain * is the only one present. */ KEG_LOCK(keg, 0); pages = keg->uk_domain[0].ud_pages; /* * 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 ((slabs = 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, 0); ret = hash_alloc(&newhash, 1 << fls(slabs)); KEG_LOCK(keg, 0); if (ret) { if (hash_expand(&keg->uk_hash, &newhash)) { oldhash = keg->uk_hash; keg->uk_hash = newhash; } else oldhash = newhash; KEG_UNLOCK(keg, 0); hash_free(&oldhash); goto update_wss; } } KEG_UNLOCK(keg, 0); update_wss: for (int i = 0; i < vm_ndomains; i++) zone_domain_update_wss(ZDOM_GET(zone, i)); } /* * 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 = 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_hash_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 (!LIST_EMPTY(&oldhash->uh_slab_hash[idx])) { slab = LIST_FIRST(&oldhash->uh_slab_hash[idx]); LIST_REMOVE(slab, uhs_hlink); hval = UMA_HASH(newhash, slab->uhs_data); LIST_INSERT_HEAD(&newhash->uh_slab_hash[hval], slab, uhs_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. * * Returns: * Nothing */ static void bucket_drain(uma_zone_t zone, uma_bucket_t bucket) { int i; if (bucket->ub_cnt == 0) return; if ((zone->uz_flags & UMA_ZONE_SMR) != 0 && bucket->ub_seq != SMR_SEQ_INVALID) { smr_wait(zone->uz_smr, bucket->ub_seq); bucket->ub_seq = SMR_SEQ_INVALID; for (i = 0; i < bucket->ub_cnt; i++) item_dtor(zone, bucket->ub_bucket[i], zone->uz_size, NULL, SKIP_NONE); } 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_free_limit(zone, bucket->ub_cnt); #ifdef INVARIANTS bzero(bucket->ub_bucket, sizeof(void *) * bucket->ub_cnt); #endif bucket->ub_cnt = 0; } /* * Drains the per cpu caches for a zone. * * NOTE: This may only be called while the zone is being torn 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; uma_bucket_t bucket; smr_seq_t seq; 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(). */ seq = SMR_SEQ_INVALID; if ((zone->uz_flags & UMA_ZONE_SMR) != 0) seq = smr_advance(zone->uz_smr); CPU_FOREACH(cpu) { cache = &zone->uz_cpu[cpu]; bucket = cache_bucket_unload_alloc(cache); if (bucket != NULL) bucket_free(zone, bucket, NULL); bucket = cache_bucket_unload_free(cache); if (bucket != NULL) { bucket->ub_seq = seq; bucket_free(zone, bucket, NULL); } bucket = cache_bucket_unload_cross(cache); if (bucket != NULL) { bucket->ub_seq = seq; bucket_free(zone, bucket, NULL); } } bucket_cache_reclaim(zone, true); } static void cache_shrink(uma_zone_t zone, void *unused) { if (zone->uz_flags & UMA_ZFLAG_INTERNAL) return; zone->uz_bucket_size = (zone->uz_bucket_size_min + zone->uz_bucket_size) / 2; } static void cache_drain_safe_cpu(uma_zone_t zone, void *unused) { uma_cache_t cache; uma_bucket_t b1, b2, b3; int domain; if (zone->uz_flags & UMA_ZFLAG_INTERNAL) return; b1 = b2 = b3 = NULL; critical_enter(); cache = &zone->uz_cpu[curcpu]; domain = PCPU_GET(domain); b1 = cache_bucket_unload_alloc(cache); /* * Don't flush SMR zone buckets. This leaves the zone without a * bucket and forces every free to synchronize(). */ if ((zone->uz_flags & UMA_ZONE_SMR) == 0) { b2 = cache_bucket_unload_free(cache); b3 = cache_bucket_unload_cross(cache); } critical_exit(); if (b1 != NULL) zone_free_bucket(zone, b1, NULL, domain, false); if (b2 != NULL) zone_free_bucket(zone, b2, NULL, domain, false); if (b3 != NULL) { /* Adjust the domain so it goes to zone_free_cross. */ domain = (domain + 1) % vm_ndomains; zone_free_bucket(zone, b3, NULL, domain, false); } } /* * 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 enough, shrink aggressively. */ if (zone) cache_shrink(zone, NULL); else zone_foreach(cache_shrink, NULL); CPU_FOREACH(cpu) { thread_lock(curthread); sched_bind(curthread, cpu); thread_unlock(curthread); if (zone) cache_drain_safe_cpu(zone, NULL); else zone_foreach(cache_drain_safe_cpu, NULL); } 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; int i; /* * Shrink the zone bucket size to ensure that the per-CPU caches * don't grow too large. */ if (zone->uz_bucket_size > zone->uz_bucket_size_min) zone->uz_bucket_size--; for (i = 0; i < vm_ndomains; i++) { /* * The cross bucket is partially filled and not part of * the item count. Reclaim it individually here. */ zdom = ZDOM_GET(zone, i); if ((zone->uz_flags & UMA_ZONE_SMR) == 0 || drain) { ZONE_CROSS_LOCK(zone); bucket = zdom->uzd_cross; zdom->uzd_cross = NULL; ZONE_CROSS_UNLOCK(zone); if (bucket != NULL) bucket_free(zone, bucket, NULL); } /* * 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. */ ZDOM_LOCK(zdom); target = drain ? 0 : lmax(zdom->uzd_wss, zdom->uzd_nitems - zdom->uzd_imin); while (zdom->uzd_nitems > target) { bucket = zone_fetch_bucket(zone, zdom, true); if (bucket == NULL) break; bucket_free(zone, bucket, NULL); ZDOM_LOCK(zdom); } ZDOM_UNLOCK(zdom); } } 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_data(slab, keg); 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_item(slab, keg, i)) || keg->uk_fini != trash_fini) #endif keg->uk_fini(slab_item(slab, keg, i), keg->uk_size); } if (keg->uk_flags & UMA_ZFLAG_OFFPAGE) zone_free_item(slabzone(keg->uk_ipers), slab_tohashslab(slab), NULL, SKIP_NONE); keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera, flags); uma_total_dec(PAGE_SIZE * keg->uk_ppera); } +static void +keg_drain_domain(uma_keg_t keg, int domain) +{ + struct slabhead freeslabs; + uma_domain_t dom; + uma_slab_t slab, tmp; + uint32_t i, stofree, stokeep, partial; + + dom = &keg->uk_domain[domain]; + LIST_INIT(&freeslabs); + + CTR4(KTR_UMA, "keg_drain %s(%p) domain %d free items: %u", + keg->uk_name, keg, i, dom->ud_free_items); + + KEG_LOCK(keg, domain); + + /* + * Are the free items in partially allocated slabs sufficient to meet + * the reserve? If not, compute the number of fully free slabs that must + * be kept. + */ + partial = dom->ud_free_items - dom->ud_free_slabs * keg->uk_ipers; + if (partial < keg->uk_reserve) { + stokeep = min(dom->ud_free_slabs, + howmany(keg->uk_reserve - partial, keg->uk_ipers)); + } else { + stokeep = 0; + } + stofree = dom->ud_free_slabs - stokeep; + + /* + * Partition the free slabs into two sets: those that must be kept in + * order to maintain the reserve, and those that may be released back to + * the system. Since one set may be much larger than the other, + * populate the smaller of the two sets and swap them if necessary. + */ + for (i = min(stofree, stokeep); i > 0; i--) { + slab = LIST_FIRST(&dom->ud_free_slab); + LIST_REMOVE(slab, us_link); + LIST_INSERT_HEAD(&freeslabs, slab, us_link); + } + if (stofree > stokeep) + LIST_SWAP(&freeslabs, &dom->ud_free_slab, uma_slab, us_link); + + if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0) { + LIST_FOREACH(slab, &freeslabs, us_link) + UMA_HASH_REMOVE(&keg->uk_hash, slab); + } + dom->ud_free_items -= stofree * keg->uk_ipers; + dom->ud_free_slabs -= stofree; + dom->ud_pages -= stofree * keg->uk_ppera; + KEG_UNLOCK(keg, domain); + + LIST_FOREACH_SAFE(slab, &freeslabs, us_link, tmp) + keg_free_slab(keg, slab, keg->uk_ipers); +} + /* * 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; - uma_domain_t dom; - uma_slab_t slab, tmp; - int i, n; + int i; - if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL) + if ((keg->uk_flags & UMA_ZONE_NOFREE) != 0) return; - - for (i = 0; i < vm_ndomains; i++) { - CTR4(KTR_UMA, "keg_drain %s(%p) domain %d free items: %u", - keg->uk_name, keg, i, dom->ud_free_items); - dom = &keg->uk_domain[i]; - LIST_INIT(&freeslabs); - - KEG_LOCK(keg, i); - if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0) { - LIST_FOREACH(slab, &dom->ud_free_slab, us_link) - UMA_HASH_REMOVE(&keg->uk_hash, slab); - } - n = dom->ud_free_slabs; - LIST_SWAP(&freeslabs, &dom->ud_free_slab, uma_slab, us_link); - dom->ud_free_slabs = 0; - dom->ud_free_items -= n * keg->uk_ipers; - dom->ud_pages -= n * keg->uk_ppera; - KEG_UNLOCK(keg, i); - - LIST_FOREACH_SAFE(slab, &freeslabs, us_link, tmp) - keg_free_slab(keg, slab, keg->uk_ipers); - } + for (i = 0; i < vm_ndomains; i++) + keg_drain_domain(keg, i); } 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, &ZDOM_GET(zone, 0)->uzd_lock, PVM, "zonedrain", 1); } zone->uz_flags |= UMA_ZFLAG_RECLAIMING; ZONE_UNLOCK(zone); bucket_cache_reclaim(zone, drain); /* * 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, void *unused) { zone_reclaim(zone, M_NOWAIT, true); } static void zone_trim(uma_zone_t zone, void *unused) { zone_reclaim(zone, M_NOWAIT, false); } /* * Allocate a new slab for a keg and inserts it into the partial slab list. * The keg should be unlocked on entry. If the allocation succeeds it will * be locked on return. * * 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_domain_t dom; 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)); allocf = keg->uk_allocf; slab = NULL; mem = NULL; if (keg->uk_flags & UMA_ZFLAG_OFFPAGE) { uma_hash_slab_t hslab; hslab = zone_alloc_item(slabzone(keg->uk_ipers), NULL, domain, aflags); if (hslab == NULL) goto fail; slab = &hslab->uhs_slab; } /* * 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_ZFLAG_OFFPAGE) zone_free_item(slabzone(keg->uk_ipers), slab_tohashslab(slab), NULL, SKIP_NONE); goto fail; } uma_total_inc(size); /* For HASH zones all pages go to the same uma_domain. */ if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0) domain = 0; /* Point the slab into the allocated memory */ if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE)) slab = (uma_slab_t )(mem + keg->uk_pgoff); else slab_tohashslab(slab)->uhs_data = mem; if (keg->uk_flags & UMA_ZFLAG_VTOSLAB) for (i = 0; i < keg->uk_ppera; i++) vsetzoneslab((vm_offset_t)mem + (i * PAGE_SIZE), zone, slab); slab->us_freecount = keg->uk_ipers; slab->us_flags = sflags; slab->us_domain = domain; BIT_FILL(keg->uk_ipers, &slab->us_free); #ifdef INVARIANTS BIT_ZERO(keg->uk_ipers, slab_dbg_bits(slab, keg)); #endif if (keg->uk_init != NULL) { for (i = 0; i < keg->uk_ipers; i++) if (keg->uk_init(slab_item(slab, keg, i), keg->uk_size, flags) != 0) break; if (i != keg->uk_ipers) { keg_free_slab(keg, slab, i); goto fail; } } KEG_LOCK(keg, domain); CTR3(KTR_UMA, "keg_alloc_slab: allocated slab %p for %s(%p)", slab, keg->uk_name, keg); if (keg->uk_flags & UMA_ZFLAG_HASH) UMA_HASH_INSERT(&keg->uk_hash, slab, mem); /* * 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. */ dom = &keg->uk_domain[domain]; LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link); dom->ud_pages += keg->uk_ppera; dom->ud_free_items += keg->uk_ipers; return (slab); fail: return (NULL); } /* * 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) { vm_paddr_t pa; vm_page_t m; void *mem; int pages; int i; pages = howmany(bytes, PAGE_SIZE); KASSERT(pages > 0, ("%s can't reserve 0 pages", __func__)); *pflag = UMA_SLAB_BOOT; m = vm_page_alloc_contig_domain(NULL, 0, domain, malloc2vm_flags(wait) | VM_ALLOC_NOOBJ | VM_ALLOC_WIRED, pages, (vm_paddr_t)0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT); if (m == NULL) return (NULL); pa = VM_PAGE_TO_PHYS(m); for (i = 0; i < pages; i++, pa += PAGE_SIZE) { #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \ defined(__riscv) || defined(__powerpc64__) if ((wait & M_NODUMP) == 0) dump_add_page(pa); #endif } /* Allocate KVA and indirectly advance bootmem. */ mem = (void *)pmap_map(&bootmem, m->phys_addr, m->phys_addr + (pages * PAGE_SIZE), VM_PROT_READ | VM_PROT_WRITE); if ((wait & M_ZERO) != 0) bzero(mem, pages * PAGE_SIZE); return (mem); } static void startup_free(void *mem, vm_size_t bytes) { vm_offset_t va; vm_page_t m; va = (vm_offset_t)mem; m = PHYS_TO_VM_PAGE(pmap_kextract(va)); pmap_remove(kernel_pmap, va, va + bytes); for (; bytes != 0; bytes -= PAGE_SIZE, m++) { #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \ defined(__riscv) || defined(__powerpc64__) dump_drop_page(VM_PAGE_TO_PHYS(m)); #endif vm_page_unwire_noq(m); vm_page_free(m); } } /* * 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); if (__predict_false(VM_DOMAIN_EMPTY(pc->pc_domain))) p = NULL; else 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); } /* * Allocate physically contiguous pages. */ static void * contig_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag, int wait) { *pflag = UMA_SLAB_KERNEL; return ((void *)kmem_alloc_contig_domainset(DOMAINSET_FIXED(domain), bytes, wait, 0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT)); } /* * 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_BOOT) != 0) { startup_free(mem, size); return; } KASSERT((flags & UMA_SLAB_KERNEL) != 0, ("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); if ((flags & UMA_SLAB_BOOT) != 0) { startup_free(mem, size); return; } 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); } #ifdef INVARIANTS static struct noslabbits * slab_dbg_bits(uma_slab_t slab, uma_keg_t keg) { return ((void *)((char *)&slab->us_free + BITSET_SIZE(keg->uk_ipers))); } #endif /* * Actual size of embedded struct slab (!OFFPAGE). */ static size_t slab_sizeof(int nitems) { size_t s; s = sizeof(struct uma_slab) + BITSET_SIZE(nitems) * SLAB_BITSETS; return (roundup(s, UMA_ALIGN_PTR + 1)); } #define UMA_FIXPT_SHIFT 31 #define UMA_FRAC_FIXPT(n, d) \ ((uint32_t)(((uint64_t)(n) << UMA_FIXPT_SHIFT) / (d))) #define UMA_FIXPT_PCT(f) \ ((u_int)(((uint64_t)100 * (f)) >> UMA_FIXPT_SHIFT)) #define UMA_PCT_FIXPT(pct) UMA_FRAC_FIXPT((pct), 100) #define UMA_MIN_EFF UMA_PCT_FIXPT(100 - UMA_MAX_WASTE) /* * Compute the number of items that will fit in a slab. If hdr is true, the * item count may be limited to provide space in the slab for an inline slab * header. Otherwise, all slab space will be provided for item storage. */ static u_int slab_ipers_hdr(u_int size, u_int rsize, u_int slabsize, bool hdr) { u_int ipers; u_int padpi; /* The padding between items is not needed after the last item. */ padpi = rsize - size; if (hdr) { /* * Start with the maximum item count and remove items until * the slab header first alongside the allocatable memory. */ for (ipers = MIN(SLAB_MAX_SETSIZE, (slabsize + padpi - slab_sizeof(1)) / rsize); ipers > 0 && ipers * rsize - padpi + slab_sizeof(ipers) > slabsize; ipers--) continue; } else { ipers = MIN((slabsize + padpi) / rsize, SLAB_MAX_SETSIZE); } return (ipers); } struct keg_layout_result { u_int format; u_int slabsize; u_int ipers; u_int eff; }; static void keg_layout_one(uma_keg_t keg, u_int rsize, u_int slabsize, u_int fmt, struct keg_layout_result *kl) { u_int total; kl->format = fmt; kl->slabsize = slabsize; /* Handle INTERNAL as inline with an extra page. */ if ((fmt & UMA_ZFLAG_INTERNAL) != 0) { kl->format &= ~UMA_ZFLAG_INTERNAL; kl->slabsize += PAGE_SIZE; } kl->ipers = slab_ipers_hdr(keg->uk_size, rsize, kl->slabsize, (fmt & UMA_ZFLAG_OFFPAGE) == 0); /* Account for memory used by an offpage slab header. */ total = kl->slabsize; if ((fmt & UMA_ZFLAG_OFFPAGE) != 0) total += slabzone(kl->ipers)->uz_keg->uk_rsize; kl->eff = UMA_FRAC_FIXPT(kl->ipers * rsize, total); } /* * Determine the format of a uma keg. This determines where the slab header * will be placed (inline or offpage) and calculates ipers, rsize, and ppera. * * Arguments * keg The zone we should initialize * * Returns * Nothing */ static void keg_layout(uma_keg_t keg) { struct keg_layout_result kl = {}, kl_tmp; u_int fmts[2]; u_int alignsize; u_int nfmt; u_int pages; u_int rsize; u_int slabsize; u_int i, j; KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 || (keg->uk_size <= UMA_PCPU_ALLOC_SIZE && (keg->uk_flags & UMA_ZONE_CACHESPREAD) == 0), ("%s: cannot configure for PCPU: keg=%s, size=%u, flags=0x%b", __func__, keg->uk_name, keg->uk_size, keg->uk_flags, PRINT_UMA_ZFLAGS)); KASSERT((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) == 0 || (keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0, ("%s: incompatible flags 0x%b", __func__, keg->uk_flags, PRINT_UMA_ZFLAGS)); alignsize = keg->uk_align + 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 = MAX(keg->uk_size, UMA_SMALLEST_UNIT); rsize = roundup2(rsize, alignsize); if ((keg->uk_flags & UMA_ZONE_CACHESPREAD) != 0) { /* * 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 & alignsize) == 0) rsize += alignsize; slabsize = rsize * (PAGE_SIZE / alignsize); slabsize = MIN(slabsize, rsize * SLAB_MAX_SETSIZE); slabsize = MIN(slabsize, UMA_CACHESPREAD_MAX_SIZE); slabsize = round_page(slabsize); } else { /* * Start with a slab size of as many pages as it takes to * represent a single item. We will try to fit as many * additional items into the slab as possible. */ slabsize = round_page(keg->uk_size); } /* Build a list of all of the available formats for this keg. */ nfmt = 0; /* Evaluate an inline slab layout. */ if ((keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0) fmts[nfmt++] = 0; /* TODO: vm_page-embedded slab. */ /* * 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_ZONE_VM, which clearly forbids it. * In those cases, evaluate a pseudo-format called INTERNAL * which has an inline slab header and one extra page to * guarantee that it fits. * * Otherwise, see if using an OFFPAGE slab will improve our * efficiency. */ if ((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) != 0) fmts[nfmt++] = UMA_ZFLAG_INTERNAL; else fmts[nfmt++] = UMA_ZFLAG_OFFPAGE; /* * Choose a slab size and format which satisfy the minimum efficiency. * Prefer the smallest slab size that meets the constraints. * * Start with a minimum slab size, to accommodate CACHESPREAD. Then, * for small items (up to PAGE_SIZE), the iteration increment is one * page; and for large items, the increment is one item. */ i = (slabsize + rsize - keg->uk_size) / MAX(PAGE_SIZE, rsize); KASSERT(i >= 1, ("keg %s(%p) flags=0x%b slabsize=%u, rsize=%u, i=%u", keg->uk_name, keg, keg->uk_flags, PRINT_UMA_ZFLAGS, slabsize, rsize, i)); for ( ; ; i++) { slabsize = (rsize <= PAGE_SIZE) ? ptoa(i) : round_page(rsize * (i - 1) + keg->uk_size); for (j = 0; j < nfmt; j++) { /* Only if we have no viable format yet. */ if ((fmts[j] & UMA_ZFLAG_INTERNAL) != 0 && kl.ipers > 0) continue; keg_layout_one(keg, rsize, slabsize, fmts[j], &kl_tmp); if (kl_tmp.eff <= kl.eff) continue; kl = kl_tmp; CTR6(KTR_UMA, "keg %s layout: format %#x " "(ipers %u * rsize %u) / slabsize %#x = %u%% eff", keg->uk_name, kl.format, kl.ipers, rsize, kl.slabsize, UMA_FIXPT_PCT(kl.eff)); /* Stop when we reach the minimum efficiency. */ if (kl.eff >= UMA_MIN_EFF) break; } if (kl.eff >= UMA_MIN_EFF || !multipage_slabs || slabsize >= SLAB_MAX_SETSIZE * rsize || (keg->uk_flags & (UMA_ZONE_PCPU | UMA_ZONE_CONTIG)) != 0) break; } pages = atop(kl.slabsize); if ((keg->uk_flags & UMA_ZONE_PCPU) != 0) pages *= mp_maxid + 1; keg->uk_rsize = rsize; keg->uk_ipers = kl.ipers; keg->uk_ppera = pages; keg->uk_flags |= kl.format; /* * How do we find the slab header if it is offpage or if not all item * start addresses are in the same page? We could solve the latter * case with vaddr alignment, but we don't. */ if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0 || (keg->uk_ipers - 1) * rsize >= PAGE_SIZE) { if ((keg->uk_flags & UMA_ZONE_NOTPAGE) != 0) keg->uk_flags |= UMA_ZFLAG_HASH; else keg->uk_flags |= UMA_ZFLAG_VTOSLAB; } CTR6(KTR_UMA, "%s: keg=%s, flags=%#x, rsize=%u, ipers=%u, ppera=%u", __func__, keg->uk_name, keg->uk_flags, rsize, keg->uk_ipers, pages); KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_MAX_SETSIZE, ("%s: keg=%s, flags=0x%b, rsize=%u, ipers=%u, ppera=%u", __func__, keg->uk_name, keg->uk_flags, PRINT_UMA_ZFLAGS, rsize, keg->uk_ipers, pages)); } /* * 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; int i; 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_reserve = 0; keg->uk_flags = arg->flags; /* * We use a global round-robin policy by default. Zones with * UMA_ZONE_FIRSTTOUCH 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 primary zone is passed to us at keg-creation time. */ zone = arg->zone; keg->uk_name = zone->uz_name; if (arg->flags & UMA_ZONE_ZINIT) keg->uk_init = zero_init; if (arg->flags & UMA_ZONE_MALLOC) keg->uk_flags |= UMA_ZFLAG_VTOSLAB; #ifndef SMP keg->uk_flags &= ~UMA_ZONE_PCPU; #endif keg_layout(keg); /* * Use a first-touch NUMA policy for kegs that pmap_extract() will * work on. Use round-robin for everything else. * * Zones may override the default by specifying either. */ #ifdef NUMA if ((keg->uk_flags & (UMA_ZONE_ROUNDROBIN | UMA_ZFLAG_CACHE | UMA_ZONE_NOTPAGE)) == 0) keg->uk_flags |= UMA_ZONE_FIRSTTOUCH; else if ((keg->uk_flags & UMA_ZONE_FIRSTTOUCH) == 0) keg->uk_flags |= UMA_ZONE_ROUNDROBIN; #endif /* * If we haven't booted yet we need allocations to go through the * startup cache until the vm is ready. */ #ifdef UMA_MD_SMALL_ALLOC if (keg->uk_ppera == 1) keg->uk_allocf = uma_small_alloc; else #endif if (booted < BOOT_KVA) keg->uk_allocf = startup_alloc; else if (keg->uk_flags & UMA_ZONE_PCPU) keg->uk_allocf = pcpu_page_alloc; else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 && keg->uk_ppera > 1) keg->uk_allocf = contig_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 locks. */ for (i = 0; i < vm_ndomains; i++) KEG_LOCK_INIT(keg, i, (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 slab_sizeof * definition. */ if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE)) { size_t shsize; shsize = slab_sizeof(keg->uk_ipers); keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - shsize; /* * 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 + shsize <= 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_ZFLAG_HASH) hash_alloc(&keg->uk_hash, 0); CTR3(KTR_UMA, "keg_ctor %p zone %s(%p)", keg, zone->uz_name, zone); 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_kva_available(uma_zone_t zone, void *unused) { uma_keg_t keg; if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0) return; KEG_GET(zone, keg); if (keg->uk_allocf == startup_alloc) { /* Switch to the real allocator. */ if (keg->uk_flags & UMA_ZONE_PCPU) keg->uk_allocf = pcpu_page_alloc; else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 && keg->uk_ppera > 1) keg->uk_allocf = contig_alloc; else keg->uk_allocf = page_alloc; } } static void zone_alloc_counters(uma_zone_t zone, void *unused) { 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->uz_xdomain = counter_u64_alloc(M_WAITOK); } static void zone_alloc_sysctl(uma_zone_t zone, void *unused) { uma_zone_domain_t zdom; uma_domain_t dom; uma_keg_t keg; struct sysctl_oid *oid, *domainoid; int domains, i, cnt; static const char *nokeg = "cache zone"; char *c; /* * Make a sysctl safe copy of the zone name by removing * any special characters and handling dups by appending * an index. */ if (zone->uz_namecnt != 0) { /* Count the number of decimal digits and '_' separator. */ for (i = 1, cnt = zone->uz_namecnt; cnt != 0; i++) cnt /= 10; zone->uz_ctlname = malloc(strlen(zone->uz_name) + i + 1, M_UMA, M_WAITOK); sprintf(zone->uz_ctlname, "%s_%d", zone->uz_name, zone->uz_namecnt); } else zone->uz_ctlname = strdup(zone->uz_name, M_UMA); for (c = zone->uz_ctlname; *c != '\0'; c++) if (strchr("./\\ -", *c) != NULL) *c = '_'; /* * Basic parameters at the root. */ zone->uz_oid = SYSCTL_ADD_NODE(NULL, SYSCTL_STATIC_CHILDREN(_vm_uma), OID_AUTO, zone->uz_ctlname, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, ""); oid = zone->uz_oid; SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "size", CTLFLAG_RD, &zone->uz_size, 0, "Allocation size"); SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "flags", CTLFLAG_RD | CTLTYPE_STRING | CTLFLAG_MPSAFE, zone, 0, sysctl_handle_uma_zone_flags, "A", "Allocator configuration flags"); SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "bucket_size", CTLFLAG_RD, &zone->uz_bucket_size, 0, "Desired per-cpu cache size"); SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "bucket_size_max", CTLFLAG_RD, &zone->uz_bucket_size_max, 0, "Maximum allowed per-cpu cache size"); /* * keg if present. */ if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0) domains = vm_ndomains; else domains = 1; oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO, "keg", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, ""); keg = zone->uz_keg; if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0) { SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "name", CTLFLAG_RD, keg->uk_name, "Keg name"); SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "rsize", CTLFLAG_RD, &keg->uk_rsize, 0, "Real object size with alignment"); SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "ppera", CTLFLAG_RD, &keg->uk_ppera, 0, "pages per-slab allocation"); SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "ipers", CTLFLAG_RD, &keg->uk_ipers, 0, "items available per-slab"); SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "align", CTLFLAG_RD, &keg->uk_align, 0, "item alignment mask"); + SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, + "reserve", CTLFLAG_RD, &keg->uk_reserve, 0, + "number of reserved items"); SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "efficiency", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE, keg, 0, sysctl_handle_uma_slab_efficiency, "I", "Slab utilization (100 - internal fragmentation %)"); domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "domain", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, ""); for (i = 0; i < domains; i++) { dom = &keg->uk_domain[i]; oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid), OID_AUTO, VM_DOMAIN(i)->vmd_name, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, ""); SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "pages", CTLFLAG_RD, &dom->ud_pages, 0, "Total pages currently allocated from VM"); SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "free_items", CTLFLAG_RD, &dom->ud_free_items, 0, "items free in the slab layer"); } } else SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "name", CTLFLAG_RD, nokeg, "Keg name"); /* * Information about zone limits. */ oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO, "limit", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, ""); SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "items", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE, zone, 0, sysctl_handle_uma_zone_items, "QU", "current number of allocated items if limit is set"); SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "max_items", CTLFLAG_RD, &zone->uz_max_items, 0, "Maximum number of cached items"); SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "sleepers", CTLFLAG_RD, &zone->uz_sleepers, 0, "Number of threads sleeping at limit"); SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "sleeps", CTLFLAG_RD, &zone->uz_sleeps, 0, "Total zone limit sleeps"); SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "bucket_max", CTLFLAG_RD, &zone->uz_bucket_max, 0, "Maximum number of items in each domain's bucket cache"); /* * Per-domain zone information. */ domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO, "domain", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, ""); for (i = 0; i < domains; i++) { zdom = ZDOM_GET(zone, i); oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid), OID_AUTO, VM_DOMAIN(i)->vmd_name, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, ""); SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "nitems", CTLFLAG_RD, &zdom->uzd_nitems, "number of items in this domain"); SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "imax", CTLFLAG_RD, &zdom->uzd_imax, "maximum item count in this period"); SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "imin", CTLFLAG_RD, &zdom->uzd_imin, "minimum item count in this period"); SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "wss", CTLFLAG_RD, &zdom->uzd_wss, "Working set size"); } /* * General statistics. */ oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO, "stats", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, ""); SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "current", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE, zone, 1, sysctl_handle_uma_zone_cur, "I", "Current number of allocated items"); SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "allocs", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE, zone, 0, sysctl_handle_uma_zone_allocs, "QU", "Total allocation calls"); SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "frees", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE, zone, 0, sysctl_handle_uma_zone_frees, "QU", "Total free calls"); SYSCTL_ADD_COUNTER_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "fails", CTLFLAG_RD, &zone->uz_fails, "Number of allocation failures"); SYSCTL_ADD_COUNTER_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "xdomain", CTLFLAG_RD, &zone->uz_xdomain, "Free calls from the wrong domain"); } struct uma_zone_count { const char *name; int count; }; static void zone_count(uma_zone_t zone, void *arg) { struct uma_zone_count *cnt; cnt = arg; /* * Some zones are rapidly created with identical names and * destroyed out of order. This can lead to gaps in the count. * Use one greater than the maximum observed for this name. */ if (strcmp(zone->uz_name, cnt->name) == 0) cnt->count = MAX(cnt->count, zone->uz_namecnt + 1); } static void zone_update_caches(uma_zone_t zone) { int i; for (i = 0; i <= mp_maxid; i++) { cache_set_uz_size(&zone->uz_cpu[i], zone->uz_size); cache_set_uz_flags(&zone->uz_cpu[i], zone->uz_flags); } } /* * 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_zone_count cnt; struct uma_zctor_args *arg = udata; uma_zone_domain_t zdom; 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_bucket_size = 0; zone->uz_bucket_size_min = 0; zone->uz_bucket_size_max = BUCKET_MAX; zone->uz_flags = (arg->flags & UMA_ZONE_SMR); zone->uz_warning = NULL; /* The domain structures follow the cpu structures. */ zone->uz_bucket_max = ULONG_MAX; timevalclear(&zone->uz_ratecheck); /* Count the number of duplicate names. */ cnt.name = arg->name; cnt.count = 0; zone_foreach(zone_count, &cnt); zone->uz_namecnt = cnt.count; ZONE_CROSS_LOCK_INIT(zone); for (i = 0; i < vm_ndomains; i++) { zdom = ZDOM_GET(zone, i); ZDOM_LOCK_INIT(zone, zdom, (arg->flags & UMA_ZONE_MTXCLASS)); STAILQ_INIT(&zdom->uzd_buckets); } #ifdef INVARIANTS if (arg->uminit == trash_init && arg->fini == trash_fini) zone->uz_flags |= UMA_ZFLAG_TRASH | UMA_ZFLAG_CTORDTOR; #endif /* * This is a pure cache zone, no kegs. */ if (arg->import) { KASSERT((arg->flags & UMA_ZFLAG_CACHE) != 0, ("zone_ctor: Import specified for non-cache zone.")); 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; #ifdef NUMA /* * Cache zones are round-robin unless a policy is * specified because they may have incompatible * constraints. */ if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) == 0) zone->uz_flags |= UMA_ZONE_ROUNDROBIN; #endif 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 = zone_import; zone->uz_release = zone_release; zone->uz_arg = zone; keg = arg->keg; if (arg->flags & UMA_ZONE_SECONDARY) { KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0, ("Secondary zone requested UMA_ZFLAG_INTERNAL")); KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg")); zone->uz_init = arg->uminit; zone->uz_fini = arg->fini; 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 & ~UMA_ZONE_SMR); karg.zone = zone; error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg, flags); if (error) return (error); } /* Inherit properties from the keg. */ zone->uz_keg = keg; zone->uz_size = keg->uk_size; zone->uz_flags |= (keg->uk_flags & (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT)); out: if (booted >= BOOT_PCPU) { zone_alloc_counters(zone, NULL); if (booted >= BOOT_RUNNING) zone_alloc_sysctl(zone, NULL); } else { zone->uz_allocs = EARLY_COUNTER; zone->uz_frees = EARLY_COUNTER; zone->uz_fails = EARLY_COUNTER; } /* Caller requests a private SMR context. */ if ((zone->uz_flags & UMA_ZONE_SMR) != 0) zone->uz_smr = smr_create(zone->uz_name, 0, 0); KASSERT((arg->flags & (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET)) != (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET), ("Invalid zone flag combination")); if (arg->flags & UMA_ZFLAG_INTERNAL) zone->uz_bucket_size_max = zone->uz_bucket_size = 0; if ((arg->flags & UMA_ZONE_MAXBUCKET) != 0) zone->uz_bucket_size = BUCKET_MAX; else if ((arg->flags & UMA_ZONE_MINBUCKET) != 0) zone->uz_bucket_size_max = zone->uz_bucket_size = BUCKET_MIN; else if ((arg->flags & UMA_ZONE_NOBUCKET) != 0) zone->uz_bucket_size = 0; else zone->uz_bucket_size = bucket_select(zone->uz_size); zone->uz_bucket_size_min = zone->uz_bucket_size; if (zone->uz_dtor != NULL || zone->uz_ctor != NULL) zone->uz_flags |= UMA_ZFLAG_CTORDTOR; zone_update_caches(zone); 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; uint32_t free, pages; int i; keg = (uma_keg_t)arg; free = pages = 0; for (i = 0; i < vm_ndomains; i++) { free += keg->uk_domain[i].ud_free_items; pages += keg->uk_domain[i].ud_pages; KEG_LOCK_FINI(keg, i); } if (pages != 0) printf("Freed UMA keg (%s) was not empty (%u items). " " Lost %u pages of memory.\n", keg->uk_name ? keg->uk_name : "", pages / keg->uk_ppera * keg->uk_ipers - free, pages); hash_free(&keg->uk_hash); } /* * 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; int i; zone = (uma_zone_t)arg; sysctl_remove_oid(zone->uz_oid, 1, 1); if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL)) cache_drain(zone); rw_wlock(&uma_rwlock); LIST_REMOVE(zone, uz_link); rw_wunlock(&uma_rwlock); 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); counter_u64_free(zone->uz_xdomain); free(zone->uz_ctlname, M_UMA); for (i = 0; i < vm_ndomains; i++) ZDOM_LOCK_FINI(ZDOM_GET(zone, i)); ZONE_CROSS_LOCK_FINI(zone); } static void zone_foreach_unlocked(void (*zfunc)(uma_zone_t, void *arg), void *arg) { uma_keg_t keg; uma_zone_t zone; LIST_FOREACH(keg, &uma_kegs, uk_link) { LIST_FOREACH(zone, &keg->uk_zones, uz_link) zfunc(zone, arg); } LIST_FOREACH(zone, &uma_cachezones, uz_link) zfunc(zone, arg); } /* * 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, void *arg), void *arg) { rw_rlock(&uma_rwlock); zone_foreach_unlocked(zfunc, arg); rw_runlock(&uma_rwlock); } /* * Initialize the kernel memory allocator. This is done after pages can be * allocated but before general KVA is available. */ void uma_startup1(vm_offset_t virtual_avail) { struct uma_zctor_args args; size_t ksize, zsize, size; uma_keg_t primarykeg; uintptr_t m; int domain; uint8_t pflag; bootstart = bootmem = virtual_avail; rw_init(&uma_rwlock, "UMA lock"); sx_init(&uma_reclaim_lock, "umareclaim"); ksize = sizeof(struct uma_keg) + (sizeof(struct uma_domain) * vm_ndomains); ksize = roundup(ksize, UMA_SUPER_ALIGN); zsize = sizeof(struct uma_zone) + (sizeof(struct uma_cache) * (mp_maxid + 1)) + (sizeof(struct uma_zone_domain) * vm_ndomains); zsize = roundup(zsize, UMA_SUPER_ALIGN); /* Allocate the zone of zones, zone of kegs, and zone of zones keg. */ size = (zsize * 2) + ksize; for (domain = 0; domain < vm_ndomains; domain++) { m = (uintptr_t)startup_alloc(NULL, size, domain, &pflag, M_NOWAIT | M_ZERO); if (m != 0) break; } zones = (uma_zone_t)m; m += zsize; kegs = (uma_zone_t)m; m += zsize; primarykeg = (uma_keg_t)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 = primarykeg; args.align = UMA_SUPER_ALIGN - 1; args.flags = UMA_ZFLAG_INTERNAL; zone_ctor(kegs, zsize, &args, M_WAITOK); 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_SUPER_ALIGN - 1; args.flags = UMA_ZFLAG_INTERNAL; zone_ctor(zones, zsize, &args, M_WAITOK); /* Now make zones for slab headers */ slabzones[0] = uma_zcreate("UMA Slabs 0", SLABZONE0_SIZE, NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL); slabzones[1] = uma_zcreate("UMA Slabs 1", SLABZONE1_SIZE, 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(); smr_init(); } #ifndef UMA_MD_SMALL_ALLOC extern void vm_radix_reserve_kva(void); #endif /* * Advertise the availability of normal kva allocations and switch to * the default back-end allocator. Marks the KVA we consumed on startup * as used in the map. */ void uma_startup2(void) { if (bootstart != bootmem) { vm_map_lock(kernel_map); (void)vm_map_insert(kernel_map, NULL, 0, bootstart, bootmem, VM_PROT_RW, VM_PROT_RW, MAP_NOFAULT); vm_map_unlock(kernel_map); } #ifndef UMA_MD_SMALL_ALLOC /* Set up radix zone to use noobj_alloc. */ vm_radix_reserve_kva(); #endif booted = BOOT_KVA; zone_foreach_unlocked(zone_kva_available, NULL); bucket_enable(); } /* * Allocate counters as early as possible so that boot-time allocations are * accounted more precisely. */ static void uma_startup_pcpu(void *arg __unused) { zone_foreach_unlocked(zone_alloc_counters, NULL); booted = BOOT_PCPU; } SYSINIT(uma_startup_pcpu, SI_SUB_COUNTER, SI_ORDER_ANY, uma_startup_pcpu, NULL); /* * Finish our initialization steps. */ static void uma_startup3(void *arg __unused) { #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_unlocked(zone_alloc_sysctl, NULL); callout_init(&uma_callout, 1); callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL); booted = BOOT_RUNNING; EVENTHANDLER_REGISTER(shutdown_post_sync, uma_shutdown, NULL, EVENTHANDLER_PRI_FIRST); } SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL); static void uma_shutdown(void) { booted = BOOT_SHUTDOWN; } 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; KASSERT(powerof2(align + 1), ("invalid zone alignment %d for \"%s\"", align, name)); /* 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 /* * Inject procedures which check for memory use after free if we are * allowed to scramble the memory while it is not allocated. This * requires that: UMA is actually able to access the memory, no init * or fini procedures, no dependency on the initial value of the * memory, and no (legitimate) use of the memory after free. Note, * the ctor and dtor do not need to be empty. */ if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOTOUCH | UMA_ZONE_NOFREE))) && uminit == NULL && fini == NULL) { args.uminit = trash_init; args.fini = trash_fini; } #endif args.align = align; args.flags = flags; args.keg = NULL; sx_slock(&uma_reclaim_lock); res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK); sx_sunlock(&uma_reclaim_lock); return (res); } /* See uma.h */ uma_zone_t uma_zsecond_create(const char *name, uma_ctor ctor, uma_dtor dtor, uma_init zinit, uma_fini zfini, uma_zone_t primary) { struct uma_zctor_args args; uma_keg_t keg; uma_zone_t res; keg = primary->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; sx_slock(&uma_reclaim_lock); res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK); sx_sunlock(&uma_reclaim_lock); return (res); } /* See uma.h */ uma_zone_t uma_zcache_create(const 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) { /* * Large slabs are expensive to reclaim, so don't bother doing * unnecessary work if we're shutting down. */ if (booted == BOOT_SHUTDOWN && zone->uz_fini == NULL && zone->uz_release == zone_release) return; 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) { if ((zone->uz_flags & UMA_ZONE_SMR) != 0) uma_zfree_smr(zone, uma_zalloc_smr(zone, M_WAITOK)); else if ((zone->uz_flags & UMA_ZONE_PCPU) != 0) uma_zfree_pcpu(zone, uma_zalloc_pcpu(zone, M_WAITOK)); else uma_zfree(zone, uma_zalloc(zone, M_WAITOK)); } void * uma_zalloc_pcpu_arg(uma_zone_t zone, void *udata, int flags) { void *item, *pcpu_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) return (NULL); pcpu_item = zpcpu_base_to_offset(item); if (flags & M_ZERO) { #ifdef SMP for (i = 0; i <= mp_maxid; i++) bzero(zpcpu_get_cpu(pcpu_item, i), zone->uz_size); #else bzero(item, zone->uz_size); #endif } return (pcpu_item); } /* * A stub while both regular and pcpu cases are identical. */ void uma_zfree_pcpu_arg(uma_zone_t zone, void *pcpu_item, void *udata) { void *item; #ifdef SMP MPASS(zone->uz_flags & UMA_ZONE_PCPU); #endif item = zpcpu_offset_to_base(pcpu_item); uma_zfree_arg(zone, item, udata); } static inline void * item_ctor(uma_zone_t zone, int uz_flags, int size, void *udata, int flags, void *item) { #ifdef INVARIANTS bool skipdbg; skipdbg = uma_dbg_zskip(zone, item); if (!skipdbg && (zone->uz_flags & UMA_ZFLAG_TRASH) != 0 && zone->uz_ctor != trash_ctor) trash_ctor(item, size, udata, flags); #endif /* Check flags before loading ctor pointer. */ if (__predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0) && __predict_false(zone->uz_ctor != NULL) && zone->uz_ctor(item, 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 (__predict_false(flags & M_ZERO)) return (memset(item, 0, size)); return (item); } static inline void item_dtor(uma_zone_t zone, void *item, int size, 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) != 0) uma_dbg_free(zone, udata, item); else uma_dbg_free(zone, NULL, item); } #endif if (__predict_true(skip < SKIP_DTOR)) { if (zone->uz_dtor != NULL) zone->uz_dtor(item, size, udata); #ifdef INVARIANTS if (!skipdbg && (zone->uz_flags & UMA_ZFLAG_TRASH) != 0 && zone->uz_dtor != trash_dtor) trash_dtor(item, size, udata); #endif } } #ifdef NUMA static int item_domain(void *item) { int domain; domain = _vm_phys_domain(vtophys(item)); KASSERT(domain >= 0 && domain < vm_ndomains, ("%s: unknown domain for item %p", __func__, item)); return (domain); } #endif #if defined(INVARIANTS) || defined(DEBUG_MEMGUARD) || defined(WITNESS) #define UMA_ZALLOC_DEBUG static int uma_zalloc_debug(uma_zone_t zone, void **itemp, void *udata, int flags) { int error; error = 0; #ifdef WITNESS if (flags & M_WAITOK) { WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "uma_zalloc_debug: zone \"%s\"", zone->uz_name); } #endif #ifdef INVARIANTS KASSERT((flags & M_EXEC) == 0, ("uma_zalloc_debug: called with M_EXEC")); KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), ("uma_zalloc_debug: called within spinlock or critical section")); KASSERT((zone->uz_flags & UMA_ZONE_PCPU) == 0 || (flags & M_ZERO) == 0, ("uma_zalloc_debug: allocating from a pcpu zone with M_ZERO")); #endif #ifdef DEBUG_MEMGUARD if ((zone->uz_flags & UMA_ZONE_SMR) == 0 && memguard_cmp_zone(zone)) { void *item; item = memguard_alloc(zone->uz_size, flags); if (item != NULL) { error = EJUSTRETURN; if (zone->uz_init != NULL && zone->uz_init(item, zone->uz_size, flags) != 0) { *itemp = NULL; return (error); } if (zone->uz_ctor != NULL && zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) { counter_u64_add(zone->uz_fails, 1); zone->uz_fini(item, zone->uz_size); *itemp = NULL; return (error); } *itemp = item; return (error); } /* This is unfortunate but should not be fatal. */ } #endif return (error); } static int uma_zfree_debug(uma_zone_t zone, void *item, void *udata) { KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), ("uma_zfree_debug: called with spinlock or critical section held")); #ifdef DEBUG_MEMGUARD if ((zone->uz_flags & UMA_ZONE_SMR) == 0 && 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 (EJUSTRETURN); } #endif return (0); } #endif static inline void * cache_alloc_item(uma_zone_t zone, uma_cache_t cache, uma_cache_bucket_t bucket, void *udata, int flags) { void *item; int size, uz_flags; item = cache_bucket_pop(cache, bucket); size = cache_uz_size(cache); uz_flags = cache_uz_flags(cache); critical_exit(); return (item_ctor(zone, uz_flags, size, udata, flags, item)); } static __noinline void * cache_alloc_retry(uma_zone_t zone, uma_cache_t cache, void *udata, int flags) { uma_cache_bucket_t bucket; int domain; while (cache_alloc(zone, cache, udata, flags)) { cache = &zone->uz_cpu[curcpu]; bucket = &cache->uc_allocbucket; if (__predict_false(bucket->ucb_cnt == 0)) continue; return (cache_alloc_item(zone, cache, bucket, udata, flags)); } critical_exit(); /* * We can not get a bucket so try to return a single item. */ if (zone->uz_flags & UMA_ZONE_FIRSTTOUCH) domain = PCPU_GET(domain); else domain = UMA_ANYDOMAIN; return (zone_alloc_item(zone, udata, domain, flags)); } /* See uma.h */ void * uma_zalloc_smr(uma_zone_t zone, int flags) { uma_cache_bucket_t bucket; uma_cache_t cache; #ifdef UMA_ZALLOC_DEBUG void *item; KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0, ("uma_zalloc_arg: called with non-SMR zone.")); if (uma_zalloc_debug(zone, &item, NULL, flags) == EJUSTRETURN) return (item); #endif critical_enter(); cache = &zone->uz_cpu[curcpu]; bucket = &cache->uc_allocbucket; if (__predict_false(bucket->ucb_cnt == 0)) return (cache_alloc_retry(zone, cache, NULL, flags)); return (cache_alloc_item(zone, cache, bucket, NULL, flags)); } /* See uma.h */ void * uma_zalloc_arg(uma_zone_t zone, void *udata, int flags) { uma_cache_bucket_t bucket; uma_cache_t cache; /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */ random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA); /* This is the fast path allocation */ CTR3(KTR_UMA, "uma_zalloc_arg zone %s(%p) flags %d", zone->uz_name, zone, flags); #ifdef UMA_ZALLOC_DEBUG void *item; KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0, ("uma_zalloc_arg: called with SMR zone.")); if (uma_zalloc_debug(zone, &item, udata, flags) == EJUSTRETURN) return (item); #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. */ critical_enter(); cache = &zone->uz_cpu[curcpu]; bucket = &cache->uc_allocbucket; if (__predict_false(bucket->ucb_cnt == 0)) return (cache_alloc_retry(zone, cache, udata, flags)); return (cache_alloc_item(zone, cache, bucket, udata, flags)); } /* * Replenish an alloc bucket and possibly restore an old one. Called in * a critical section. Returns in a critical section. * * A false return value indicates an allocation failure. * A true return value indicates success and the caller should retry. */ static __noinline bool cache_alloc(uma_zone_t zone, uma_cache_t cache, void *udata, int flags) { uma_bucket_t bucket; int curdomain, domain; bool new; CRITICAL_ASSERT(curthread); /* * If we have run out of items in our alloc bucket see * if we can switch with the free bucket. * * SMR Zones can't re-use the free bucket until the sequence has * expired. */ if ((cache_uz_flags(cache) & UMA_ZONE_SMR) == 0 && cache->uc_freebucket.ucb_cnt != 0) { cache_bucket_swap(&cache->uc_freebucket, &cache->uc_allocbucket); return (true); } /* * Discard any empty allocation bucket while we hold no locks. */ bucket = cache_bucket_unload_alloc(cache); critical_exit(); if (bucket != NULL) { KASSERT(bucket->ub_cnt == 0, ("cache_alloc: Entered with non-empty alloc bucket.")); bucket_free(zone, bucket, udata); } /* * Attempt to retrieve the item from the per-CPU cache has failed, so * we must go back to the zone. This requires the zdom 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. */ domain = PCPU_GET(domain); if ((cache_uz_flags(cache) & UMA_ZONE_ROUNDROBIN) != 0 || VM_DOMAIN_EMPTY(domain)) domain = zone_domain_highest(zone, domain); bucket = cache_fetch_bucket(zone, cache, domain); if (bucket == NULL && zone->uz_bucket_size != 0 && !bucketdisable) { bucket = zone_alloc_bucket(zone, udata, domain, flags); new = true; } else { new = false; } CTR3(KTR_UMA, "uma_zalloc: zone %s(%p) bucket zone returned %p", zone->uz_name, zone, bucket); if (bucket == NULL) { critical_enter(); return (false); } /* * See if we lost the race or were migrated. Cache the * initialized bucket to make this less likely or claim * the memory directly. */ critical_enter(); cache = &zone->uz_cpu[curcpu]; if (cache->uc_allocbucket.ucb_bucket == NULL && ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) == 0 || (curdomain = PCPU_GET(domain)) == domain || VM_DOMAIN_EMPTY(curdomain))) { if (new) atomic_add_long(&ZDOM_GET(zone, domain)->uzd_imax, bucket->ub_cnt); cache_bucket_load_alloc(cache, bucket); return (true); } /* * We lost the race, release this bucket and start over. */ critical_exit(); zone_put_bucket(zone, domain, bucket, udata, false); critical_enter(); return (true); } void * uma_zalloc_domain(uma_zone_t zone, void *udata, int domain, int flags) { #ifdef NUMA uma_bucket_t bucket; uma_zone_domain_t zdom; void *item; #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_domain zone %s(%p) domain %d flags %d", 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")); KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0, ("uma_zalloc_domain: called with SMR zone.")); #ifdef NUMA KASSERT((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0, ("uma_zalloc_domain: called with non-FIRSTTOUCH zone.")); if (vm_ndomains == 1) return (uma_zalloc_arg(zone, udata, flags)); /* * Try to allocate from the bucket cache before falling back to the keg. * We could try harder and attempt to allocate from per-CPU caches or * the per-domain cross-domain buckets, but the complexity is probably * not worth it. It is more important that frees of previous * cross-domain allocations do not blow up the cache. */ zdom = zone_domain_lock(zone, domain); if ((bucket = zone_fetch_bucket(zone, zdom, false)) != NULL) { item = bucket->ub_bucket[bucket->ub_cnt - 1]; #ifdef INVARIANTS bucket->ub_bucket[bucket->ub_cnt - 1] = NULL; #endif bucket->ub_cnt--; zone_put_bucket(zone, domain, bucket, udata, true); item = item_ctor(zone, zone->uz_flags, zone->uz_size, udata, flags, item); if (item != NULL) { KASSERT(item_domain(item) == domain, ("%s: bucket cache item %p from wrong domain", __func__, item)); counter_u64_add(zone->uz_allocs, 1); } return (item); } ZDOM_UNLOCK(zdom); return (zone_alloc_item(zone, udata, domain, flags)); #else return (uma_zalloc_arg(zone, udata, flags)); #endif } /* * 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, domain); slab = NULL; start = domain; do { dom = &keg->uk_domain[domain]; if ((slab = LIST_FIRST(&dom->ud_part_slab)) != NULL) return (slab); if ((slab = LIST_FIRST(&dom->ud_free_slab)) != NULL) { LIST_REMOVE(slab, us_link); dom->ud_free_slabs--; LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link); return (slab); } if (rr) domain = (domain + 1) % vm_ndomains; } while (domain != start); return (NULL); } /* * Fetch an existing slab from a free or partial list. Returns with the * keg domain lock held if a slab was found or unlocked if not. */ static uma_slab_t keg_fetch_free_slab(uma_keg_t keg, int domain, bool rr, int flags) { uma_slab_t slab; uint32_t reserve; /* HASH has a single free list. */ if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0) domain = 0; KEG_LOCK(keg, domain); reserve = (flags & M_USE_RESERVE) != 0 ? 0 : keg->uk_reserve; if (keg->uk_domain[domain].ud_free_items <= reserve || (slab = keg_first_slab(keg, domain, rr)) == NULL) { KEG_UNLOCK(keg, domain); return (NULL); } return (slab); } 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_slab_t slab; int aflags, domain; bool rr; restart: /* * 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) return (slab); /* * M_NOVM means don't ask at all! */ if (flags & M_NOVM) break; slab = keg_alloc_slab(keg, zone, domain, flags, aflags); if (slab != NULL) return (slab); if (!rr && (flags & M_WAITOK) == 0) break; if (rr && vm_domainset_iter_policy(&di, &domain) != 0) { if ((flags & M_WAITOK) != 0) { vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask, 0); 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) return (slab); return (NULL); } static void * slab_alloc_item(uma_keg_t keg, uma_slab_t slab) { uma_domain_t dom; void *item; int freei; KEG_LOCK_ASSERT(keg, slab->us_domain); dom = &keg->uk_domain[slab->us_domain]; freei = BIT_FFS(keg->uk_ipers, &slab->us_free) - 1; BIT_CLR(keg->uk_ipers, freei, &slab->us_free); item = slab_item(slab, keg, freei); slab->us_freecount--; dom->ud_free_items--; /* * Move this slab to the full list. It must be on the partial list, so * we do not need to update the free slab count. In particular, * keg_fetch_slab() always returns slabs on the partial list. */ if (slab->us_freecount == 0) { LIST_REMOVE(slab, us_link); LIST_INSERT_HEAD(&dom->ud_full_slab, slab, us_link); } return (item); } static int zone_import(void *arg, void **bucket, int max, int domain, int flags) { uma_domain_t dom; uma_zone_t zone; uma_slab_t slab; uma_keg_t keg; #ifdef NUMA int stripe; #endif int i; zone = arg; slab = NULL; keg = zone->uz_keg; /* Try to keep the buckets totally full */ for (i = 0; i < max; ) { if ((slab = keg_fetch_slab(keg, zone, domain, flags)) == NULL) break; #ifdef NUMA stripe = howmany(max, vm_ndomains); #endif dom = &keg->uk_domain[slab->us_domain]; do { bucket[i++] = slab_alloc_item(keg, slab); if (dom->ud_free_items <= keg->uk_reserve) { /* * Avoid depleting the reserve after a * successful item allocation, even if * M_USE_RESERVE is specified. */ KEG_UNLOCK(keg, slab->us_domain); goto out; } #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_ROUNDROBIN) != 0 && vm_ndomains > 1 && --stripe == 0) break; #endif } while (slab->us_freecount != 0 && i < max); KEG_UNLOCK(keg, slab->us_domain); /* Don't block if we allocated any successfully. */ flags &= ~M_WAITOK; flags |= M_NOWAIT; } out: return i; } static int zone_alloc_limit_hard(uma_zone_t zone, int count, int flags) { uint64_t old, new, total, max; /* * The hard case. We're going to sleep because there were existing * sleepers or because we ran out of items. This routine enforces * fairness by keeping fifo order. * * First release our ill gotten gains and make some noise. */ for (;;) { zone_free_limit(zone, count); zone_log_warning(zone); zone_maxaction(zone); if (flags & M_NOWAIT) return (0); /* * We need to allocate an item or set ourself as a sleeper * while the sleepq lock is held to avoid wakeup races. This * is essentially a home rolled semaphore. */ sleepq_lock(&zone->uz_max_items); old = zone->uz_items; do { MPASS(UZ_ITEMS_SLEEPERS(old) < UZ_ITEMS_SLEEPERS_MAX); /* Cache the max since we will evaluate twice. */ max = zone->uz_max_items; if (UZ_ITEMS_SLEEPERS(old) != 0 || UZ_ITEMS_COUNT(old) >= max) new = old + UZ_ITEMS_SLEEPER; else new = old + MIN(count, max - old); } while (atomic_fcmpset_64(&zone->uz_items, &old, new) == 0); /* We may have successfully allocated under the sleepq lock. */ if (UZ_ITEMS_SLEEPERS(new) == 0) { sleepq_release(&zone->uz_max_items); return (new - old); } /* * This is in a different cacheline from uz_items so that we * don't constantly invalidate the fastpath cacheline when we * adjust item counts. This could be limited to toggling on * transitions. */ atomic_add_32(&zone->uz_sleepers, 1); atomic_add_64(&zone->uz_sleeps, 1); /* * We have added ourselves as a sleeper. The sleepq lock * protects us from wakeup races. Sleep now and then retry. */ sleepq_add(&zone->uz_max_items, NULL, "zonelimit", 0, 0); sleepq_wait(&zone->uz_max_items, PVM); /* * After wakeup, remove ourselves as a sleeper and try * again. We no longer have the sleepq lock for protection. * * Subract ourselves as a sleeper while attempting to add * our count. */ atomic_subtract_32(&zone->uz_sleepers, 1); old = atomic_fetchadd_64(&zone->uz_items, -(UZ_ITEMS_SLEEPER - count)); /* We're no longer a sleeper. */ old -= UZ_ITEMS_SLEEPER; /* * If we're still at the limit, restart. Notably do not * block on other sleepers. Cache the max value to protect * against changes via sysctl. */ total = UZ_ITEMS_COUNT(old); max = zone->uz_max_items; if (total >= max) continue; /* Truncate if necessary, otherwise wake other sleepers. */ if (total + count > max) { zone_free_limit(zone, total + count - max); count = max - total; } else if (total + count < max && UZ_ITEMS_SLEEPERS(old) != 0) wakeup_one(&zone->uz_max_items); return (count); } } /* * Allocate 'count' items from our max_items limit. Returns the number * available. If M_NOWAIT is not specified it will sleep until at least * one item can be allocated. */ static int zone_alloc_limit(uma_zone_t zone, int count, int flags) { uint64_t old; uint64_t max; max = zone->uz_max_items; MPASS(max > 0); /* * We expect normal allocations to succeed with a simple * fetchadd. */ old = atomic_fetchadd_64(&zone->uz_items, count); if (__predict_true(old + count <= max)) return (count); /* * If we had some items and no sleepers just return the * truncated value. We have to release the excess space * though because that may wake sleepers who weren't woken * because we were temporarily over the limit. */ if (old < max) { zone_free_limit(zone, (old + count) - max); return (max - old); } return (zone_alloc_limit_hard(zone, count, flags)); } /* * Free a number of items back to the limit. */ static void zone_free_limit(uma_zone_t zone, int count) { uint64_t old; MPASS(count > 0); /* * In the common case we either have no sleepers or * are still over the limit and can just return. */ old = atomic_fetchadd_64(&zone->uz_items, -count); if (__predict_true(UZ_ITEMS_SLEEPERS(old) == 0 || UZ_ITEMS_COUNT(old) - count >= zone->uz_max_items)) return; /* * Moderate the rate of wakeups. Sleepers will continue * to generate wakeups if necessary. */ wakeup_one(&zone->uz_max_items); } static uma_bucket_t zone_alloc_bucket(uma_zone_t zone, void *udata, int domain, int flags) { uma_bucket_t bucket; int maxbucket, cnt; CTR3(KTR_UMA, "zone_alloc_bucket zone %s(%p) domain %d", zone->uz_name, zone, domain); /* Avoid allocs targeting empty domains. */ if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain)) domain = UMA_ANYDOMAIN; else if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0) domain = UMA_ANYDOMAIN; if (zone->uz_max_items > 0) maxbucket = zone_alloc_limit(zone, zone->uz_bucket_size, M_NOWAIT); else maxbucket = zone->uz_bucket_size; if (maxbucket == 0) return (false); /* Don't wait for buckets, preserve caller's NOVM setting. */ bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM)); if (bucket == NULL) { cnt = 0; goto out; } bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket, MIN(maxbucket, 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; } } cnt = bucket->ub_cnt; if (bucket->ub_cnt == 0) { bucket_free(zone, bucket, udata); counter_u64_add(zone->uz_fails, 1); bucket = NULL; } out: if (zone->uz_max_items > 0 && cnt < maxbucket) zone_free_limit(zone, maxbucket - cnt); 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) { void *item; if (zone->uz_max_items > 0 && zone_alloc_limit(zone, 1, flags) == 0) { counter_u64_add(zone->uz_fails, 1); return (NULL); } /* 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_cnt; /* * 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_cnt; } } item = item_ctor(zone, zone->uz_flags, zone->uz_size, udata, flags, item); if (item == NULL) goto fail; 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_cnt: counter_u64_add(zone->uz_fails, 1); fail: if (zone->uz_max_items > 0) zone_free_limit(zone, 1); CTR2(KTR_UMA, "zone_alloc_item failed from %s(%p)", zone->uz_name, zone); return (NULL); } /* See uma.h */ void uma_zfree_smr(uma_zone_t zone, void *item) { uma_cache_t cache; uma_cache_bucket_t bucket; int itemdomain, uz_flags; #ifdef UMA_ZALLOC_DEBUG KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0, ("uma_zfree_smr: called with non-SMR zone.")); KASSERT(item != NULL, ("uma_zfree_smr: Called with NULL pointer.")); SMR_ASSERT_NOT_ENTERED(zone->uz_smr); if (uma_zfree_debug(zone, item, NULL) == EJUSTRETURN) return; #endif cache = &zone->uz_cpu[curcpu]; uz_flags = cache_uz_flags(cache); itemdomain = 0; #ifdef NUMA if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0) itemdomain = item_domain(item); #endif critical_enter(); do { cache = &zone->uz_cpu[curcpu]; /* SMR Zones must free to the free bucket. */ bucket = &cache->uc_freebucket; #ifdef NUMA if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 && PCPU_GET(domain) != itemdomain) { bucket = &cache->uc_crossbucket; } #endif if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) { cache_bucket_push(cache, bucket, item); critical_exit(); return; } } while (cache_free(zone, cache, NULL, item, itemdomain)); critical_exit(); /* * If nothing else caught this, we'll just do an internal free. */ zone_free_item(zone, item, NULL, SKIP_NONE); } /* See uma.h */ void uma_zfree_arg(uma_zone_t zone, void *item, void *udata) { uma_cache_t cache; uma_cache_bucket_t bucket; int itemdomain, uz_flags; /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */ random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA); CTR2(KTR_UMA, "uma_zfree_arg zone %s(%p)", zone->uz_name, zone); #ifdef UMA_ZALLOC_DEBUG KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0, ("uma_zfree_arg: called with SMR zone.")); if (uma_zfree_debug(zone, item, udata) == EJUSTRETURN) return; #endif /* uma_zfree(..., NULL) does nothing, to match free(9). */ if (item == NULL) return; /* * We are accessing the per-cpu cache without a critical section to * fetch size and flags. This is acceptable, if we are preempted we * will simply read another cpu's line. */ cache = &zone->uz_cpu[curcpu]; uz_flags = cache_uz_flags(cache); if (UMA_ALWAYS_CTORDTOR || __predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0)) item_dtor(zone, item, cache_uz_size(cache), udata, SKIP_NONE); /* * 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 (__predict_false(uz_flags & UMA_ZFLAG_LIMIT)) { if (zone->uz_sleepers > 0) goto zfree_item; } /* * 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. */ itemdomain = 0; #ifdef NUMA if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0) itemdomain = item_domain(item); #endif critical_enter(); do { cache = &zone->uz_cpu[curcpu]; /* * 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. */ bucket = &cache->uc_allocbucket; #ifdef NUMA if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 && PCPU_GET(domain) != itemdomain) { bucket = &cache->uc_crossbucket; } else #endif if (bucket->ucb_cnt == bucket->ucb_entries && cache->uc_freebucket.ucb_cnt < cache->uc_freebucket.ucb_entries) cache_bucket_swap(&cache->uc_freebucket, &cache->uc_allocbucket); if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) { cache_bucket_push(cache, bucket, item); critical_exit(); return; } } while (cache_free(zone, cache, udata, item, itemdomain)); critical_exit(); /* * If nothing else caught this, we'll just do an internal free. */ zfree_item: zone_free_item(zone, item, udata, SKIP_DTOR); } #ifdef NUMA /* * sort crossdomain free buckets to domain correct buckets and cache * them. */ static void zone_free_cross(uma_zone_t zone, uma_bucket_t bucket, void *udata) { struct uma_bucketlist fullbuckets; uma_zone_domain_t zdom; uma_bucket_t b; smr_seq_t seq; void *item; int domain; CTR3(KTR_UMA, "uma_zfree: zone %s(%p) draining cross bucket %p", zone->uz_name, zone, bucket); /* * It is possible for buckets to arrive here out of order so we fetch * the current smr seq rather than accepting the bucket's. */ seq = SMR_SEQ_INVALID; if ((zone->uz_flags & UMA_ZONE_SMR) != 0) seq = smr_advance(zone->uz_smr); /* * To avoid having ndomain * ndomain buckets for sorting we have a * lock on the current crossfree bucket. A full matrix with * per-domain locking could be used if necessary. */ STAILQ_INIT(&fullbuckets); ZONE_CROSS_LOCK(zone); while (bucket->ub_cnt > 0) { item = bucket->ub_bucket[bucket->ub_cnt - 1]; domain = item_domain(item); zdom = ZDOM_GET(zone, domain); if (zdom->uzd_cross == NULL) { zdom->uzd_cross = bucket_alloc(zone, udata, M_NOWAIT); if (zdom->uzd_cross == NULL) break; } b = zdom->uzd_cross; b->ub_bucket[b->ub_cnt++] = item; b->ub_seq = seq; if (b->ub_cnt == b->ub_entries) { STAILQ_INSERT_HEAD(&fullbuckets, b, ub_link); zdom->uzd_cross = NULL; } bucket->ub_cnt--; } ZONE_CROSS_UNLOCK(zone); if (bucket->ub_cnt == 0) bucket->ub_seq = SMR_SEQ_INVALID; bucket_free(zone, bucket, udata); while ((b = STAILQ_FIRST(&fullbuckets)) != NULL) { STAILQ_REMOVE_HEAD(&fullbuckets, ub_link); domain = item_domain(b->ub_bucket[0]); zone_put_bucket(zone, domain, b, udata, true); } } #endif static void zone_free_bucket(uma_zone_t zone, uma_bucket_t bucket, void *udata, int itemdomain, bool ws) { #ifdef NUMA /* * Buckets coming from the wrong domain will be entirely for the * only other domain on two domain systems. In this case we can * simply cache them. Otherwise we need to sort them back to * correct domains. */ if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 && vm_ndomains > 2 && PCPU_GET(domain) != itemdomain) { zone_free_cross(zone, bucket, udata); return; } #endif /* * Attempt to save the bucket in the zone's domain bucket cache. */ 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 */ if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0) itemdomain = zone_domain_lowest(zone, itemdomain); zone_put_bucket(zone, itemdomain, bucket, udata, ws); } /* * Populate a free or cross bucket for the current cpu cache. Free any * existing full bucket either to the zone cache or back to the slab layer. * * Enters and returns in a critical section. false return indicates that * we can not satisfy this free in the cache layer. true indicates that * the caller should retry. */ static __noinline bool cache_free(uma_zone_t zone, uma_cache_t cache, void *udata, void *item, int itemdomain) { uma_cache_bucket_t cbucket; uma_bucket_t newbucket, bucket; CRITICAL_ASSERT(curthread); if (zone->uz_bucket_size == 0) return false; cache = &zone->uz_cpu[curcpu]; newbucket = NULL; /* * FIRSTTOUCH domains need to free to the correct zdom. When * enabled this is the zdom of the item. The bucket is the * cross bucket if the current domain and itemdomain do not match. */ cbucket = &cache->uc_freebucket; #ifdef NUMA if ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) != 0) { if (PCPU_GET(domain) != itemdomain) { cbucket = &cache->uc_crossbucket; if (cbucket->ucb_cnt != 0) counter_u64_add(zone->uz_xdomain, cbucket->ucb_cnt); } } #endif bucket = cache_bucket_unload(cbucket); KASSERT(bucket == NULL || bucket->ub_cnt == bucket->ub_entries, ("cache_free: Entered with non-full free bucket.")); /* We are no longer associated with this CPU. */ critical_exit(); /* * Don't let SMR zones operate without a free bucket. Force * a synchronize and re-use this one. We will only degrade * to a synchronize every bucket_size items rather than every * item if we fail to allocate a bucket. */ if ((zone->uz_flags & UMA_ZONE_SMR) != 0) { if (bucket != NULL) bucket->ub_seq = smr_advance(zone->uz_smr); newbucket = bucket_alloc(zone, udata, M_NOWAIT); if (newbucket == NULL && bucket != NULL) { bucket_drain(zone, bucket); newbucket = bucket; bucket = NULL; } } else if (!bucketdisable) newbucket = bucket_alloc(zone, udata, M_NOWAIT); if (bucket != NULL) zone_free_bucket(zone, bucket, udata, itemdomain, true); critical_enter(); if ((bucket = newbucket) == NULL) return (false); cache = &zone->uz_cpu[curcpu]; #ifdef NUMA /* * Check to see if we should be populating the cross bucket. If it * is already populated we will fall through and attempt to populate * the free bucket. */ if ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) != 0) { if (PCPU_GET(domain) != itemdomain && cache->uc_crossbucket.ucb_bucket == NULL) { cache_bucket_load_cross(cache, bucket); return (true); } } #endif /* * We may have lost the race to fill the bucket or switched CPUs. */ if (cache->uc_freebucket.ucb_bucket != NULL) { critical_exit(); bucket_free(zone, bucket, udata); critical_enter(); } else cache_bucket_load_free(cache, bucket); return (true); } static void slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item) { uma_keg_t keg; uma_domain_t dom; int freei; keg = zone->uz_keg; KEG_LOCK_ASSERT(keg, slab->us_domain); /* Do we need to remove from any lists? */ dom = &keg->uk_domain[slab->us_domain]; if (slab->us_freecount + 1 == keg->uk_ipers) { LIST_REMOVE(slab, us_link); LIST_INSERT_HEAD(&dom->ud_free_slab, slab, us_link); dom->ud_free_slabs++; } else if (slab->us_freecount == 0) { LIST_REMOVE(slab, us_link); LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link); } /* Slab management. */ freei = slab_item_index(slab, keg, item); BIT_SET(keg->uk_ipers, freei, &slab->us_free); slab->us_freecount++; /* Keg statistics. */ dom->ud_free_items++; } static void zone_release(void *arg, void **bucket, int cnt) { struct mtx *lock; uma_zone_t zone; uma_slab_t slab; uma_keg_t keg; uint8_t *mem; void *item; int i; zone = arg; keg = zone->uz_keg; lock = NULL; if (__predict_false((zone->uz_flags & UMA_ZFLAG_HASH) != 0)) lock = KEG_LOCK(keg, 0); for (i = 0; i < cnt; i++) { item = bucket[i]; if (__predict_true((zone->uz_flags & UMA_ZFLAG_VTOSLAB) != 0)) { slab = vtoslab((vm_offset_t)item); } else { mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK)); if ((zone->uz_flags & UMA_ZFLAG_HASH) != 0) slab = hash_sfind(&keg->uk_hash, mem); else slab = (uma_slab_t)(mem + keg->uk_pgoff); } if (lock != KEG_LOCKPTR(keg, slab->us_domain)) { if (lock != NULL) mtx_unlock(lock); lock = KEG_LOCK(keg, slab->us_domain); } slab_free_item(zone, slab, item); } if (lock != NULL) mtx_unlock(lock); } /* * 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 __noinline void zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip) { /* * If a free is sent directly to an SMR zone we have to * synchronize immediately because the item can instantly * be reallocated. This should only happen in degenerate * cases when no memory is available for per-cpu caches. */ if ((zone->uz_flags & UMA_ZONE_SMR) != 0 && skip == SKIP_NONE) smr_synchronize(zone->uz_smr); item_dtor(zone, item, zone->uz_size, udata, skip); 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_free_limit(zone, 1); } /* See uma.h */ int uma_zone_set_max(uma_zone_t zone, int nitems) { struct uma_bucket_zone *ubz; int count; /* * XXX This can misbehave if the zone has any allocations with * no limit and a limit is imposed. There is currently no * way to clear a limit. */ ZONE_LOCK(zone); ubz = bucket_zone_max(zone, nitems); count = ubz != NULL ? ubz->ubz_entries : 0; zone->uz_bucket_size_max = zone->uz_bucket_size = count; if (zone->uz_bucket_size_min > zone->uz_bucket_size_max) zone->uz_bucket_size_min = zone->uz_bucket_size_max; zone->uz_max_items = nitems; zone->uz_flags |= UMA_ZFLAG_LIMIT; zone_update_caches(zone); /* We may need to wake waiters. */ wakeup(&zone->uz_max_items); ZONE_UNLOCK(zone); return (nitems); } /* See uma.h */ 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; if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0) /* Count the cross-domain bucket. */ bpcpu++; nitems -= ubz->ubz_entries * bpcpu * mp_ncpus; zone->uz_bucket_size_max = ubz->ubz_entries; } else { zone->uz_bucket_size_max = zone->uz_bucket_size = 0; } if (zone->uz_bucket_size_min > zone->uz_bucket_size_max) zone->uz_bucket_size_min = zone->uz_bucket_size_max; zone->uz_bucket_max = nitems / vm_ndomains; ZONE_UNLOCK(zone); } /* See uma.h */ int uma_zone_get_max(uma_zone_t zone) { int nitems; nitems = atomic_load_64(&zone->uz_max_items); return (nitems); } /* See uma.h */ void uma_zone_set_warning(uma_zone_t zone, const char *warning) { ZONE_ASSERT_COLD(zone); zone->uz_warning = warning; } /* See uma.h */ void uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction) { ZONE_ASSERT_COLD(zone); TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone); } /* See uma.h */ int uma_zone_get_cur(uma_zone_t zone) { int64_t nitems; u_int i; nitems = 0; if (zone->uz_allocs != EARLY_COUNTER && zone->uz_frees != EARLY_COUNTER) nitems = counter_u64_fetch(zone->uz_allocs) - counter_u64_fetch(zone->uz_frees); CPU_FOREACH(i) nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs) - atomic_load_64(&zone->uz_cpu[i].uc_frees); return (nitems < 0 ? 0 : nitems); } static uint64_t uma_zone_get_allocs(uma_zone_t zone) { uint64_t nitems; u_int i; nitems = 0; if (zone->uz_allocs != EARLY_COUNTER) nitems = counter_u64_fetch(zone->uz_allocs); CPU_FOREACH(i) nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs); return (nitems); } static uint64_t uma_zone_get_frees(uma_zone_t zone) { uint64_t nitems; u_int i; nitems = 0; if (zone->uz_frees != EARLY_COUNTER) nitems = counter_u64_fetch(zone->uz_frees); CPU_FOREACH(i) nitems += atomic_load_64(&zone->uz_cpu[i].uc_frees); return (nitems); } #ifdef INVARIANTS /* Used only for KEG_ASSERT_COLD(). */ static uint64_t uma_keg_get_allocs(uma_keg_t keg) { uma_zone_t z; uint64_t nitems; nitems = 0; LIST_FOREACH(z, &keg->uk_zones, uz_link) nitems += uma_zone_get_allocs(z); return (nitems); } #endif /* See uma.h */ void uma_zone_set_init(uma_zone_t zone, uma_init uminit) { uma_keg_t keg; KEG_GET(zone, keg); KEG_ASSERT_COLD(keg); keg->uk_init = uminit; } /* See uma.h */ void uma_zone_set_fini(uma_zone_t zone, uma_fini fini) { uma_keg_t keg; KEG_GET(zone, keg); KEG_ASSERT_COLD(keg); keg->uk_fini = fini; } /* See uma.h */ void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit) { ZONE_ASSERT_COLD(zone); zone->uz_init = zinit; } /* See uma.h */ void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini) { ZONE_ASSERT_COLD(zone); zone->uz_fini = zfini; } /* See uma.h */ void uma_zone_set_freef(uma_zone_t zone, uma_free freef) { uma_keg_t keg; KEG_GET(zone, keg); KEG_ASSERT_COLD(keg); keg->uk_freef = freef; } /* See uma.h */ void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf) { uma_keg_t keg; KEG_GET(zone, keg); KEG_ASSERT_COLD(keg); keg->uk_allocf = allocf; } /* See uma.h */ void uma_zone_set_smr(uma_zone_t zone, smr_t smr) { ZONE_ASSERT_COLD(zone); KASSERT(smr != NULL, ("Got NULL smr")); KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0, ("zone %p (%s) already uses SMR", zone, zone->uz_name)); zone->uz_flags |= UMA_ZONE_SMR; zone->uz_smr = smr; zone_update_caches(zone); } smr_t uma_zone_get_smr(uma_zone_t zone) { return (zone->uz_smr); } /* See uma.h */ void uma_zone_reserve(uma_zone_t zone, int items) { uma_keg_t keg; KEG_GET(zone, keg); KEG_ASSERT_COLD(keg); keg->uk_reserve = items; } /* 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); KEG_ASSERT_COLD(keg); ZONE_ASSERT_COLD(zone); pages = howmany(count, keg->uk_ipers) * 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; 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_ZFLAG_LIMIT | UMA_ZONE_NOFREE; zone->uz_flags |= UMA_ZFLAG_LIMIT | UMA_ZONE_NOFREE; zone_update_caches(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); slabs = howmany(items, keg->uk_ipers); 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) { dom = &keg->uk_domain[slab->us_domain]; /* * keg_alloc_slab() always returns a slab on the * partial list. */ LIST_REMOVE(slab, us_link); LIST_INSERT_HEAD(&dom->ud_free_slab, slab, us_link); dom->ud_free_slabs++; KEG_UNLOCK(keg, slab->us_domain); break; } if (vm_domainset_iter_policy(&di, &domain) != 0) vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask, 0); } } } /* * Returns a snapshot of memory consumption in bytes. */ size_t uma_zone_memory(uma_zone_t zone) { size_t sz; int i; sz = 0; if (zone->uz_flags & UMA_ZFLAG_CACHE) { for (i = 0; i < vm_ndomains; i++) sz += ZDOM_GET(zone, i)->uzd_nitems; return (sz * zone->uz_size); } for (i = 0; i < vm_ndomains; i++) sz += zone->uz_keg->uk_domain[i].ud_pages; return (sz * PAGE_SIZE); } /* 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, NULL); break; case UMA_RECLAIM_DRAIN: case UMA_RECLAIM_DRAIN_CPU: zone_foreach(zone_drain, NULL); if (req == UMA_RECLAIM_DRAIN_CPU) { pcpu_cache_drain_safe(NULL); zone_foreach(zone_drain, NULL); } 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(slabzones[0], NULL); zone_drain(slabzones[1], NULL); 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, NULL); break; case UMA_RECLAIM_DRAIN: zone_drain(zone, NULL); break; case UMA_RECLAIM_DRAIN_CPU: pcpu_cache_drain_safe(zone); zone_drain(zone, NULL); break; default: panic("unhandled reclamation request %d", req); } } /* See uma.h */ int uma_zone_exhausted(uma_zone_t zone) { return (atomic_load_32(&zone->uz_sleepers) > 0); } 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()); } #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. * */ 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]; cachefree += cache->uc_allocbucket.ucb_cnt; cachefree += cache->uc_freebucket.ucb_cnt; xdomain += cache->uc_crossbucket.ucb_cnt; cachefree += cache->uc_crossbucket.ucb_cnt; allocs += cache->uc_allocs; frees += cache->uc_frees; } allocs += counter_u64_fetch(z->uz_allocs); frees += counter_u64_fetch(z->uz_frees); xdomain += counter_u64_fetch(z->uz_xdomain); sleeps += z->uz_sleeps; 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_cache_t cache; int i; for (i = 0; i < vm_ndomains; i++) { zdom = ZDOM_GET(z, 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_xdomain = counter_u64_fetch(z->uz_xdomain); uth->uth_sleeps = z->uz_sleeps; for (i = 0; i < mp_maxid + 1; i++) { bzero(&ups[i], sizeof(*ups)); if (internal || CPU_ABSENT(i)) continue; cache = &z->uz_cpu[i]; ups[i].ups_cache_free += cache->uc_allocbucket.ucb_cnt; ups[i].ups_cache_free += cache->uc_freebucket.ucb_cnt; ups[i].ups_cache_free += cache->uc_crossbucket.ucb_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; uint64_t items; uint32_t kfree, pages; 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) { kfree = pages = 0; for (i = 0; i < vm_ndomains; i++) { kfree += kz->uk_domain[i].ud_free_items; pages += kz->uk_domain[i].ud_pages; } LIST_FOREACH(z, &kz->uk_zones, uz_link) { bzero(&uth, sizeof(uth)); 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) { items = UZ_ITEMS_COUNT(z->uz_items); uth.uth_pages = (items / kz->uk_ipers) * kz->uk_ppera; } else uth.uth_pages = 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 = kfree; /* * 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); (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)); 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); (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; int cur; /* * Some callers want to add sysctls for global zones that * may not yet exist so they pass a pointer to a pointer. */ if (arg2 == 0) zone = *(uma_zone_t *)arg1; else zone = arg1; cur = uma_zone_get_cur(zone); return (sysctl_handle_int(oidp, &cur, 0, req)); } static int sysctl_handle_uma_zone_allocs(SYSCTL_HANDLER_ARGS) { uma_zone_t zone = arg1; uint64_t cur; cur = uma_zone_get_allocs(zone); return (sysctl_handle_64(oidp, &cur, 0, req)); } static int sysctl_handle_uma_zone_frees(SYSCTL_HANDLER_ARGS) { uma_zone_t zone = arg1; uint64_t cur; cur = uma_zone_get_frees(zone); return (sysctl_handle_64(oidp, &cur, 0, req)); } static int sysctl_handle_uma_zone_flags(SYSCTL_HANDLER_ARGS) { struct sbuf sbuf; uma_zone_t zone = arg1; int error; sbuf_new_for_sysctl(&sbuf, NULL, 0, req); if (zone->uz_flags != 0) sbuf_printf(&sbuf, "0x%b", zone->uz_flags, PRINT_UMA_ZFLAGS); else sbuf_printf(&sbuf, "0"); error = sbuf_finish(&sbuf); sbuf_delete(&sbuf); return (error); } static int sysctl_handle_uma_slab_efficiency(SYSCTL_HANDLER_ARGS) { uma_keg_t keg = arg1; int avail, effpct, total; total = keg->uk_ppera * PAGE_SIZE; if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0) total += slabzone(keg->uk_ipers)->uz_keg->uk_rsize; /* * We consider the client's requested size and alignment here, not the * real size determination uk_rsize, because we also adjust the real * size for internal implementation reasons (max bitset size). */ avail = keg->uk_ipers * roundup2(keg->uk_size, keg->uk_align + 1); if ((keg->uk_flags & UMA_ZONE_PCPU) != 0) avail *= mp_maxid + 1; effpct = 100 * avail / total; return (sysctl_handle_int(oidp, &effpct, 0, req)); } static int sysctl_handle_uma_zone_items(SYSCTL_HANDLER_ARGS) { uma_zone_t zone = arg1; uint64_t cur; cur = UZ_ITEMS_COUNT(atomic_load_64(&zone->uz_items)); return (sysctl_handle_64(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; /* * It is safe to return the slab here even though the * zone is unlocked because the item's allocation state * essentially holds a reference. */ mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK)); if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0) return (NULL); if (zone->uz_flags & UMA_ZFLAG_VTOSLAB) return (vtoslab((vm_offset_t)mem)); keg = zone->uz_keg; if ((keg->uk_flags & UMA_ZFLAG_HASH) == 0) return ((uma_slab_t)(mem + keg->uk_pgoff)); KEG_LOCK(keg, 0); slab = hash_sfind(&keg->uk_hash, mem); KEG_UNLOCK(keg, 0); return (slab); } static bool uma_dbg_zskip(uma_zone_t zone, void *mem) { if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0) 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", item, zone->uz_name); } keg = zone->uz_keg; freei = slab_item_index(slab, keg, item); if (BIT_ISSET(keg->uk_ipers, freei, slab_dbg_bits(slab, keg))) panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)", item, zone, zone->uz_name, slab, freei); BIT_SET_ATOMIC(keg->uk_ipers, freei, slab_dbg_bits(slab, keg)); } /* * 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", item, zone->uz_name); } keg = zone->uz_keg; freei = slab_item_index(slab, keg, item); if (freei >= keg->uk_ipers) panic("Invalid free of %p from zone %p(%s) slab %p(%d)", item, zone, zone->uz_name, slab, freei); if (slab_item(slab, keg, freei) != item) panic("Unaligned free of %p from zone %p(%s) slab %p(%d)", item, zone, zone->uz_name, slab, freei); if (!BIT_ISSET(keg->uk_ipers, freei, slab_dbg_bits(slab, keg))) panic("Duplicate free of %p from zone %p(%s) slab %p(%d)", item, zone, zone->uz_name, slab, freei); BIT_CLR_ATOMIC(keg->uk_ipers, freei, slab_dbg_bits(slab, keg)); } #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); for (i = 0; i < vm_ndomains; i++) { *cachefree += ZDOM_GET(z, i)->uzd_nitems; if (!((z->uz_flags & UMA_ZONE_SECONDARY) && (LIST_FIRST(&kz->uk_zones) != z))) *cachefree += kz->uk_domain[i].ud_free_items; } *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_bucket_size, (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 += ZDOM_GET(z, 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_bucket_size); if (db_pager_quit) return; } } #endif /* DDB */