Index: head/sys/kern/subr_witness.c =================================================================== --- head/sys/kern/subr_witness.c (revision 331367) +++ head/sys/kern/subr_witness.c (revision 331368) @@ -1,3055 +1,3071 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 2008 Isilon Systems, Inc. * Copyright (c) 2008 Ilya Maykov * Copyright (c) 1998 Berkeley Software Design, Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Berkeley Software Design Inc's name may not be used to endorse or * promote products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``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 BERKELEY SOFTWARE DESIGN INC BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from BSDI $Id: mutex_witness.c,v 1.1.2.20 2000/04/27 03:10:27 cp Exp $ * and BSDI $Id: synch_machdep.c,v 2.3.2.39 2000/04/27 03:10:25 cp Exp $ */ /* * Implementation of the `witness' lock verifier. Originally implemented for * mutexes in BSD/OS. Extended to handle generic lock objects and lock * classes in FreeBSD. */ /* * Main Entry: witness * Pronunciation: 'wit-n&s * Function: noun * Etymology: Middle English witnesse, from Old English witnes knowledge, * testimony, witness, from 2wit * Date: before 12th century * 1 : attestation of a fact or event : TESTIMONY * 2 : one that gives evidence; specifically : one who testifies in * a cause or before a judicial tribunal * 3 : one asked to be present at a transaction so as to be able to * testify to its having taken place * 4 : one who has personal knowledge of something * 5 a : something serving as evidence or proof : SIGN * b : public affirmation by word or example of usually * religious faith or conviction * 6 capitalized : a member of the Jehovah's Witnesses */ /* * Special rules concerning Giant and lock orders: * * 1) Giant must be acquired before any other mutexes. Stated another way, * no other mutex may be held when Giant is acquired. * * 2) Giant must be released when blocking on a sleepable lock. * * This rule is less obvious, but is a result of Giant providing the same * semantics as spl(). Basically, when a thread sleeps, it must release * Giant. When a thread blocks on a sleepable lock, it sleeps. Hence rule * 2). * * 3) Giant may be acquired before or after sleepable locks. * * This rule is also not quite as obvious. Giant may be acquired after * a sleepable lock because it is a non-sleepable lock and non-sleepable * locks may always be acquired while holding a sleepable lock. The second * case, Giant before a sleepable lock, follows from rule 2) above. Suppose * you have two threads T1 and T2 and a sleepable lock X. Suppose that T1 * acquires X and blocks on Giant. Then suppose that T2 acquires Giant and * blocks on X. When T2 blocks on X, T2 will release Giant allowing T1 to * execute. Thus, acquiring Giant both before and after a sleepable lock * will not result in a lock order reversal. */ #include __FBSDID("$FreeBSD$"); #include "opt_ddb.h" #include "opt_hwpmc_hooks.h" #include "opt_stack.h" #include "opt_witness.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef DDB #include #endif #include #if !defined(DDB) && !defined(STACK) #error "DDB or STACK options are required for WITNESS" #endif /* Note that these traces do not work with KTR_ALQ. */ #if 0 #define KTR_WITNESS KTR_SUBSYS #else #define KTR_WITNESS 0 #endif #define LI_RECURSEMASK 0x0000ffff /* Recursion depth of lock instance. */ #define LI_EXCLUSIVE 0x00010000 /* Exclusive lock instance. */ #define LI_NORELEASE 0x00020000 /* Lock not allowed to be released. */ /* Define this to check for blessed mutexes */ #undef BLESSING #ifndef WITNESS_COUNT #define WITNESS_COUNT 1536 #endif #define WITNESS_HASH_SIZE 251 /* Prime, gives load factor < 2 */ -#define WITNESS_PENDLIST (2048 + (MAXCPU * 4)) +#define WITNESS_PENDLIST (512 + (MAXCPU * 4)) /* Allocate 256 KB of stack data space */ #define WITNESS_LO_DATA_COUNT 2048 /* Prime, gives load factor of ~2 at full load */ #define WITNESS_LO_HASH_SIZE 1021 /* * XXX: This is somewhat bogus, as we assume here that at most 2048 threads * will hold LOCK_NCHILDREN locks. We handle failure ok, and we should * probably be safe for the most part, but it's still a SWAG. */ #define LOCK_NCHILDREN 5 #define LOCK_CHILDCOUNT 2048 #define MAX_W_NAME 64 #define FULLGRAPH_SBUF_SIZE 512 /* * These flags go in the witness relationship matrix and describe the * relationship between any two struct witness objects. */ #define WITNESS_UNRELATED 0x00 /* No lock order relation. */ #define WITNESS_PARENT 0x01 /* Parent, aka direct ancestor. */ #define WITNESS_ANCESTOR 0x02 /* Direct or indirect ancestor. */ #define WITNESS_CHILD 0x04 /* Child, aka direct descendant. */ #define WITNESS_DESCENDANT 0x08 /* Direct or indirect descendant. */ #define WITNESS_ANCESTOR_MASK (WITNESS_PARENT | WITNESS_ANCESTOR) #define WITNESS_DESCENDANT_MASK (WITNESS_CHILD | WITNESS_DESCENDANT) #define WITNESS_RELATED_MASK \ (WITNESS_ANCESTOR_MASK | WITNESS_DESCENDANT_MASK) #define WITNESS_REVERSAL 0x10 /* A lock order reversal has been * observed. */ #define WITNESS_RESERVED1 0x20 /* Unused flag, reserved. */ #define WITNESS_RESERVED2 0x40 /* Unused flag, reserved. */ #define WITNESS_LOCK_ORDER_KNOWN 0x80 /* This lock order is known. */ /* Descendant to ancestor flags */ #define WITNESS_DTOA(x) (((x) & WITNESS_RELATED_MASK) >> 2) /* Ancestor to descendant flags */ #define WITNESS_ATOD(x) (((x) & WITNESS_RELATED_MASK) << 2) #define WITNESS_INDEX_ASSERT(i) \ MPASS((i) > 0 && (i) <= w_max_used_index && (i) < witness_count) static MALLOC_DEFINE(M_WITNESS, "Witness", "Witness"); /* * Lock instances. A lock instance is the data associated with a lock while * it is held by witness. For example, a lock instance will hold the * recursion count of a lock. Lock instances are held in lists. Spin locks * are held in a per-cpu list while sleep locks are held in per-thread list. */ struct lock_instance { struct lock_object *li_lock; const char *li_file; int li_line; u_int li_flags; }; /* * A simple list type used to build the list of locks held by a thread * or CPU. We can't simply embed the list in struct lock_object since a * lock may be held by more than one thread if it is a shared lock. Locks * are added to the head of the list, so we fill up each list entry from * "the back" logically. To ease some of the arithmetic, we actually fill * in each list entry the normal way (children[0] then children[1], etc.) but * when we traverse the list we read children[count-1] as the first entry * down to children[0] as the final entry. */ struct lock_list_entry { struct lock_list_entry *ll_next; struct lock_instance ll_children[LOCK_NCHILDREN]; u_int ll_count; }; /* * The main witness structure. One of these per named lock type in the system * (for example, "vnode interlock"). */ struct witness { char w_name[MAX_W_NAME]; uint32_t w_index; /* Index in the relationship matrix */ struct lock_class *w_class; STAILQ_ENTRY(witness) w_list; /* List of all witnesses. */ STAILQ_ENTRY(witness) w_typelist; /* Witnesses of a type. */ struct witness *w_hash_next; /* Linked list in hash buckets. */ const char *w_file; /* File where last acquired */ uint32_t w_line; /* Line where last acquired */ uint32_t w_refcount; uint16_t w_num_ancestors; /* direct/indirect * ancestor count */ uint16_t w_num_descendants; /* direct/indirect * descendant count */ int16_t w_ddb_level; unsigned w_displayed:1; unsigned w_reversed:1; }; STAILQ_HEAD(witness_list, witness); /* * The witness hash table. Keys are witness names (const char *), elements are * witness objects (struct witness *). */ struct witness_hash { struct witness *wh_array[WITNESS_HASH_SIZE]; uint32_t wh_size; uint32_t wh_count; }; /* * Key type for the lock order data hash table. */ struct witness_lock_order_key { uint16_t from; uint16_t to; }; struct witness_lock_order_data { struct stack wlod_stack; struct witness_lock_order_key wlod_key; struct witness_lock_order_data *wlod_next; }; /* * The witness lock order data hash table. Keys are witness index tuples * (struct witness_lock_order_key), elements are lock order data objects * (struct witness_lock_order_data). */ struct witness_lock_order_hash { struct witness_lock_order_data *wloh_array[WITNESS_LO_HASH_SIZE]; u_int wloh_size; u_int wloh_count; }; #ifdef BLESSING struct witness_blessed { const char *b_lock1; const char *b_lock2; }; #endif struct witness_pendhelp { const char *wh_type; struct lock_object *wh_lock; }; struct witness_order_list_entry { const char *w_name; struct lock_class *w_class; }; /* * Returns 0 if one of the locks is a spin lock and the other is not. * Returns 1 otherwise. */ static __inline int witness_lock_type_equal(struct witness *w1, struct witness *w2) { return ((w1->w_class->lc_flags & (LC_SLEEPLOCK | LC_SPINLOCK)) == (w2->w_class->lc_flags & (LC_SLEEPLOCK | LC_SPINLOCK))); } static __inline int witness_lock_order_key_equal(const struct witness_lock_order_key *a, const struct witness_lock_order_key *b) { return (a->from == b->from && a->to == b->to); } static int _isitmyx(struct witness *w1, struct witness *w2, int rmask, const char *fname); static void adopt(struct witness *parent, struct witness *child); #ifdef BLESSING static int blessed(struct witness *, struct witness *); #endif static void depart(struct witness *w); static struct witness *enroll(const char *description, struct lock_class *lock_class); static struct lock_instance *find_instance(struct lock_list_entry *list, const struct lock_object *lock); static int isitmychild(struct witness *parent, struct witness *child); static int isitmydescendant(struct witness *parent, struct witness *child); static void itismychild(struct witness *parent, struct witness *child); static int sysctl_debug_witness_badstacks(SYSCTL_HANDLER_ARGS); static int sysctl_debug_witness_watch(SYSCTL_HANDLER_ARGS); static int sysctl_debug_witness_fullgraph(SYSCTL_HANDLER_ARGS); static int sysctl_debug_witness_channel(SYSCTL_HANDLER_ARGS); static void witness_add_fullgraph(struct sbuf *sb, struct witness *parent); #ifdef DDB static void witness_ddb_compute_levels(void); static void witness_ddb_display(int(*)(const char *fmt, ...)); static void witness_ddb_display_descendants(int(*)(const char *fmt, ...), struct witness *, int indent); static void witness_ddb_display_list(int(*prnt)(const char *fmt, ...), struct witness_list *list); static void witness_ddb_level_descendants(struct witness *parent, int l); static void witness_ddb_list(struct thread *td); #endif static void witness_debugger(int cond, const char *msg); static void witness_free(struct witness *m); static struct witness *witness_get(void); static uint32_t witness_hash_djb2(const uint8_t *key, uint32_t size); static struct witness *witness_hash_get(const char *key); static void witness_hash_put(struct witness *w); static void witness_init_hash_tables(void); static void witness_increment_graph_generation(void); static void witness_lock_list_free(struct lock_list_entry *lle); static struct lock_list_entry *witness_lock_list_get(void); static int witness_lock_order_add(struct witness *parent, struct witness *child); static int witness_lock_order_check(struct witness *parent, struct witness *child); static struct witness_lock_order_data *witness_lock_order_get( struct witness *parent, struct witness *child); static void witness_list_lock(struct lock_instance *instance, int (*prnt)(const char *fmt, ...)); static int witness_output(const char *fmt, ...) __printflike(1, 2); static int witness_voutput(const char *fmt, va_list ap) __printflike(1, 0); static void witness_setflag(struct lock_object *lock, int flag, int set); static SYSCTL_NODE(_debug, OID_AUTO, witness, CTLFLAG_RW, NULL, "Witness Locking"); /* * If set to 0, lock order checking is disabled. If set to -1, * witness is completely disabled. Otherwise witness performs full * lock order checking for all locks. At runtime, lock order checking * may be toggled. However, witness cannot be reenabled once it is * completely disabled. */ static int witness_watch = 1; SYSCTL_PROC(_debug_witness, OID_AUTO, watch, CTLFLAG_RWTUN | CTLTYPE_INT, NULL, 0, sysctl_debug_witness_watch, "I", "witness is watching lock operations"); #ifdef KDB /* * When KDB is enabled and witness_kdb is 1, it will cause the system * to drop into kdebug() when: * - a lock hierarchy violation occurs * - locks are held when going to sleep. */ #ifdef WITNESS_KDB int witness_kdb = 1; #else int witness_kdb = 0; #endif SYSCTL_INT(_debug_witness, OID_AUTO, kdb, CTLFLAG_RWTUN, &witness_kdb, 0, ""); #endif /* KDB */ #if defined(DDB) || defined(KDB) /* * When DDB or KDB is enabled and witness_trace is 1, it will cause the system * to print a stack trace: * - a lock hierarchy violation occurs * - locks are held when going to sleep. */ int witness_trace = 1; SYSCTL_INT(_debug_witness, OID_AUTO, trace, CTLFLAG_RWTUN, &witness_trace, 0, ""); #endif /* DDB || KDB */ #ifdef WITNESS_SKIPSPIN int witness_skipspin = 1; #else int witness_skipspin = 0; #endif SYSCTL_INT(_debug_witness, OID_AUTO, skipspin, CTLFLAG_RDTUN, &witness_skipspin, 0, ""); int badstack_sbuf_size; int witness_count = WITNESS_COUNT; SYSCTL_INT(_debug_witness, OID_AUTO, witness_count, CTLFLAG_RDTUN, &witness_count, 0, ""); /* * Output channel for witness messages. By default we print to the console. */ enum witness_channel { WITNESS_CONSOLE, WITNESS_LOG, WITNESS_NONE, }; static enum witness_channel witness_channel = WITNESS_CONSOLE; SYSCTL_PROC(_debug_witness, OID_AUTO, output_channel, CTLTYPE_STRING | CTLFLAG_RWTUN, NULL, 0, sysctl_debug_witness_channel, "A", "Output channel for warnings"); /* * Call this to print out the relations between locks. */ SYSCTL_PROC(_debug_witness, OID_AUTO, fullgraph, CTLTYPE_STRING | CTLFLAG_RD, NULL, 0, sysctl_debug_witness_fullgraph, "A", "Show locks relation graphs"); /* * Call this to print out the witness faulty stacks. */ SYSCTL_PROC(_debug_witness, OID_AUTO, badstacks, CTLTYPE_STRING | CTLFLAG_RD, NULL, 0, sysctl_debug_witness_badstacks, "A", "Show bad witness stacks"); static struct mtx w_mtx; /* w_list */ static struct witness_list w_free = STAILQ_HEAD_INITIALIZER(w_free); static struct witness_list w_all = STAILQ_HEAD_INITIALIZER(w_all); /* w_typelist */ static struct witness_list w_spin = STAILQ_HEAD_INITIALIZER(w_spin); static struct witness_list w_sleep = STAILQ_HEAD_INITIALIZER(w_sleep); /* lock list */ static struct lock_list_entry *w_lock_list_free = NULL; static struct witness_pendhelp pending_locks[WITNESS_PENDLIST]; static u_int pending_cnt; static int w_free_cnt, w_spin_cnt, w_sleep_cnt; SYSCTL_INT(_debug_witness, OID_AUTO, free_cnt, CTLFLAG_RD, &w_free_cnt, 0, ""); SYSCTL_INT(_debug_witness, OID_AUTO, spin_cnt, CTLFLAG_RD, &w_spin_cnt, 0, ""); SYSCTL_INT(_debug_witness, OID_AUTO, sleep_cnt, CTLFLAG_RD, &w_sleep_cnt, 0, ""); static struct witness *w_data; static uint8_t **w_rmatrix; static struct lock_list_entry w_locklistdata[LOCK_CHILDCOUNT]; static struct witness_hash w_hash; /* The witness hash table. */ /* The lock order data hash */ static struct witness_lock_order_data w_lodata[WITNESS_LO_DATA_COUNT]; static struct witness_lock_order_data *w_lofree = NULL; static struct witness_lock_order_hash w_lohash; static int w_max_used_index = 0; static unsigned int w_generation = 0; static const char w_notrunning[] = "Witness not running\n"; static const char w_stillcold[] = "Witness is still cold\n"; static struct witness_order_list_entry order_lists[] = { /* * sx locks */ { "proctree", &lock_class_sx }, { "allproc", &lock_class_sx }, { "allprison", &lock_class_sx }, { NULL, NULL }, /* * Various mutexes */ { "Giant", &lock_class_mtx_sleep }, { "pipe mutex", &lock_class_mtx_sleep }, { "sigio lock", &lock_class_mtx_sleep }, { "process group", &lock_class_mtx_sleep }, { "process lock", &lock_class_mtx_sleep }, { "session", &lock_class_mtx_sleep }, { "uidinfo hash", &lock_class_rw }, #ifdef HWPMC_HOOKS { "pmc-sleep", &lock_class_mtx_sleep }, #endif { "time lock", &lock_class_mtx_sleep }, { NULL, NULL }, /* * umtx */ { "umtx lock", &lock_class_mtx_sleep }, { NULL, NULL }, /* * Sockets */ { "accept", &lock_class_mtx_sleep }, { "so_snd", &lock_class_mtx_sleep }, { "so_rcv", &lock_class_mtx_sleep }, { "sellck", &lock_class_mtx_sleep }, { NULL, NULL }, /* * Routing */ { "so_rcv", &lock_class_mtx_sleep }, { "radix node head", &lock_class_rw }, { "rtentry", &lock_class_mtx_sleep }, { "ifaddr", &lock_class_mtx_sleep }, { NULL, NULL }, /* * IPv4 multicast: * protocol locks before interface locks, after UDP locks. */ { "udpinp", &lock_class_rw }, { "in_multi_mtx", &lock_class_mtx_sleep }, { "igmp_mtx", &lock_class_mtx_sleep }, { "if_addr_lock", &lock_class_rw }, { NULL, NULL }, /* * IPv6 multicast: * protocol locks before interface locks, after UDP locks. */ { "udpinp", &lock_class_rw }, { "in6_multi_mtx", &lock_class_mtx_sleep }, { "mld_mtx", &lock_class_mtx_sleep }, { "if_addr_lock", &lock_class_rw }, { NULL, NULL }, /* * UNIX Domain Sockets */ { "unp_link_rwlock", &lock_class_rw }, { "unp_list_lock", &lock_class_mtx_sleep }, { "unp", &lock_class_mtx_sleep }, { "so_snd", &lock_class_mtx_sleep }, { NULL, NULL }, /* * UDP/IP */ { "udp", &lock_class_rw }, { "udpinp", &lock_class_rw }, { "so_snd", &lock_class_mtx_sleep }, { NULL, NULL }, /* * TCP/IP */ { "tcp", &lock_class_rw }, { "tcpinp", &lock_class_rw }, { "so_snd", &lock_class_mtx_sleep }, { NULL, NULL }, /* * BPF */ { "bpf global lock", &lock_class_mtx_sleep }, { "bpf interface lock", &lock_class_rw }, { "bpf cdev lock", &lock_class_mtx_sleep }, { NULL, NULL }, /* * NFS server */ { "nfsd_mtx", &lock_class_mtx_sleep }, { "so_snd", &lock_class_mtx_sleep }, { NULL, NULL }, /* * IEEE 802.11 */ { "802.11 com lock", &lock_class_mtx_sleep}, { NULL, NULL }, /* * Network drivers */ { "network driver", &lock_class_mtx_sleep}, { NULL, NULL }, /* * Netgraph */ { "ng_node", &lock_class_mtx_sleep }, { "ng_worklist", &lock_class_mtx_sleep }, { NULL, NULL }, /* * CDEV */ { "vm map (system)", &lock_class_mtx_sleep }, { "vm pagequeue", &lock_class_mtx_sleep }, { "vnode interlock", &lock_class_mtx_sleep }, { "cdev", &lock_class_mtx_sleep }, { NULL, NULL }, /* * VM */ { "vm map (user)", &lock_class_sx }, { "vm object", &lock_class_rw }, { "vm page", &lock_class_mtx_sleep }, { "vm pagequeue", &lock_class_mtx_sleep }, { "pmap pv global", &lock_class_rw }, { "pmap", &lock_class_mtx_sleep }, { "pmap pv list", &lock_class_rw }, { "vm page free queue", &lock_class_mtx_sleep }, { NULL, NULL }, /* * kqueue/VFS interaction */ { "kqueue", &lock_class_mtx_sleep }, { "struct mount mtx", &lock_class_mtx_sleep }, { "vnode interlock", &lock_class_mtx_sleep }, { NULL, NULL }, /* * VFS namecache */ { "ncvn", &lock_class_mtx_sleep }, { "ncbuc", &lock_class_rw }, { "vnode interlock", &lock_class_mtx_sleep }, { "ncneg", &lock_class_mtx_sleep }, { NULL, NULL }, /* * ZFS locking */ { "dn->dn_mtx", &lock_class_sx }, { "dr->dt.di.dr_mtx", &lock_class_sx }, { "db->db_mtx", &lock_class_sx }, { NULL, NULL }, /* * TCP log locks */ { "TCP ID tree", &lock_class_rw }, { "tcp log id bucket", &lock_class_mtx_sleep }, { "tcpinp", &lock_class_rw }, { "TCP log expireq", &lock_class_mtx_sleep }, { NULL, NULL }, /* * spin locks */ #ifdef SMP { "ap boot", &lock_class_mtx_spin }, #endif { "rm.mutex_mtx", &lock_class_mtx_spin }, { "sio", &lock_class_mtx_spin }, #ifdef __i386__ { "cy", &lock_class_mtx_spin }, #endif #ifdef __sparc64__ { "pcib_mtx", &lock_class_mtx_spin }, { "rtc_mtx", &lock_class_mtx_spin }, #endif { "scc_hwmtx", &lock_class_mtx_spin }, { "uart_hwmtx", &lock_class_mtx_spin }, { "fast_taskqueue", &lock_class_mtx_spin }, { "intr table", &lock_class_mtx_spin }, #ifdef HWPMC_HOOKS { "pmc-per-proc", &lock_class_mtx_spin }, #endif { "process slock", &lock_class_mtx_spin }, { "syscons video lock", &lock_class_mtx_spin }, { "sleepq chain", &lock_class_mtx_spin }, { "rm_spinlock", &lock_class_mtx_spin }, { "turnstile chain", &lock_class_mtx_spin }, { "turnstile lock", &lock_class_mtx_spin }, { "sched lock", &lock_class_mtx_spin }, { "td_contested", &lock_class_mtx_spin }, { "callout", &lock_class_mtx_spin }, { "entropy harvest mutex", &lock_class_mtx_spin }, #ifdef SMP { "smp rendezvous", &lock_class_mtx_spin }, #endif #ifdef __powerpc__ { "tlb0", &lock_class_mtx_spin }, #endif /* * leaf locks */ { "intrcnt", &lock_class_mtx_spin }, { "icu", &lock_class_mtx_spin }, #if defined(SMP) && defined(__sparc64__) { "ipi", &lock_class_mtx_spin }, #endif #ifdef __i386__ { "allpmaps", &lock_class_mtx_spin }, { "descriptor tables", &lock_class_mtx_spin }, #endif { "clk", &lock_class_mtx_spin }, { "cpuset", &lock_class_mtx_spin }, { "mprof lock", &lock_class_mtx_spin }, { "zombie lock", &lock_class_mtx_spin }, { "ALD Queue", &lock_class_mtx_spin }, #if defined(__i386__) || defined(__amd64__) { "pcicfg", &lock_class_mtx_spin }, { "NDIS thread lock", &lock_class_mtx_spin }, #endif { "tw_osl_io_lock", &lock_class_mtx_spin }, { "tw_osl_q_lock", &lock_class_mtx_spin }, { "tw_cl_io_lock", &lock_class_mtx_spin }, { "tw_cl_intr_lock", &lock_class_mtx_spin }, { "tw_cl_gen_lock", &lock_class_mtx_spin }, #ifdef HWPMC_HOOKS { "pmc-leaf", &lock_class_mtx_spin }, #endif { "blocked lock", &lock_class_mtx_spin }, { NULL, NULL }, { NULL, NULL } }; #ifdef BLESSING /* * Pairs of locks which have been blessed * Don't complain about order problems with blessed locks */ static struct witness_blessed blessed_list[] = { }; #endif /* * This global is set to 0 once it becomes safe to use the witness code. */ static int witness_cold = 1; /* * This global is set to 1 once the static lock orders have been enrolled * so that a warning can be issued for any spin locks enrolled later. */ static int witness_spin_warn = 0; /* Trim useless garbage from filenames. */ static const char * fixup_filename(const char *file) { if (file == NULL) return (NULL); while (strncmp(file, "../", 3) == 0) file += 3; return (file); } /* + * Calculate the size of early witness structures. + */ +int +witness_startup_count(void) +{ + int sz; + + sz = sizeof(struct witness) * witness_count; + sz += sizeof(*w_rmatrix) * (witness_count + 1); + sz += sizeof(*w_rmatrix[0]) * (witness_count + 1) * + (witness_count + 1); + + return (sz); +} + +/* * The WITNESS-enabled diagnostic code. Note that the witness code does * assume that the early boot is single-threaded at least until after this * routine is completed. */ -static void -witness_initialize(void *dummy __unused) +void +witness_startup(void *mem) { struct lock_object *lock; struct witness_order_list_entry *order; struct witness *w, *w1; + uintptr_t p; int i; - w_data = malloc(sizeof (struct witness) * witness_count, M_WITNESS, - M_WAITOK | M_ZERO); + p = (uintptr_t)mem; + w_data = (void *)p; + p += sizeof(struct witness) * witness_count; - w_rmatrix = malloc(sizeof(*w_rmatrix) * (witness_count + 1), - M_WITNESS, M_WAITOK | M_ZERO); + w_rmatrix = (void *)p; + p += sizeof(*w_rmatrix) * (witness_count + 1); for (i = 0; i < witness_count + 1; i++) { - w_rmatrix[i] = malloc(sizeof(*w_rmatrix[i]) * - (witness_count + 1), M_WITNESS, M_WAITOK | M_ZERO); + w_rmatrix[i] = (void *)p; + p += sizeof(*w_rmatrix[i]) * (witness_count + 1); } badstack_sbuf_size = witness_count * 256; /* * We have to release Giant before initializing its witness * structure so that WITNESS doesn't get confused. */ mtx_unlock(&Giant); mtx_assert(&Giant, MA_NOTOWNED); CTR1(KTR_WITNESS, "%s: initializing witness", __func__); mtx_init(&w_mtx, "witness lock", NULL, MTX_SPIN | MTX_QUIET | MTX_NOWITNESS | MTX_NOPROFILE); for (i = witness_count - 1; i >= 0; i--) { w = &w_data[i]; memset(w, 0, sizeof(*w)); w_data[i].w_index = i; /* Witness index never changes. */ witness_free(w); } KASSERT(STAILQ_FIRST(&w_free)->w_index == 0, ("%s: Invalid list of free witness objects", __func__)); /* Witness with index 0 is not used to aid in debugging. */ STAILQ_REMOVE_HEAD(&w_free, w_list); w_free_cnt--; for (i = 0; i < witness_count; i++) { memset(w_rmatrix[i], 0, sizeof(*w_rmatrix[i]) * (witness_count + 1)); } for (i = 0; i < LOCK_CHILDCOUNT; i++) witness_lock_list_free(&w_locklistdata[i]); witness_init_hash_tables(); /* First add in all the specified order lists. */ for (order = order_lists; order->w_name != NULL; order++) { w = enroll(order->w_name, order->w_class); if (w == NULL) continue; w->w_file = "order list"; for (order++; order->w_name != NULL; order++) { w1 = enroll(order->w_name, order->w_class); if (w1 == NULL) continue; w1->w_file = "order list"; itismychild(w, w1); w = w1; } } witness_spin_warn = 1; /* Iterate through all locks and add them to witness. */ for (i = 0; pending_locks[i].wh_lock != NULL; i++) { lock = pending_locks[i].wh_lock; KASSERT(lock->lo_flags & LO_WITNESS, ("%s: lock %s is on pending list but not LO_WITNESS", __func__, lock->lo_name)); lock->lo_witness = enroll(pending_locks[i].wh_type, LOCK_CLASS(lock)); } /* Mark the witness code as being ready for use. */ witness_cold = 0; mtx_lock(&Giant); } -SYSINIT(witness_init, SI_SUB_WITNESS, SI_ORDER_FIRST, witness_initialize, - NULL); void witness_init(struct lock_object *lock, const char *type) { struct lock_class *class; /* Various sanity checks. */ class = LOCK_CLASS(lock); if ((lock->lo_flags & LO_RECURSABLE) != 0 && (class->lc_flags & LC_RECURSABLE) == 0) kassert_panic("%s: lock (%s) %s can not be recursable", __func__, class->lc_name, lock->lo_name); if ((lock->lo_flags & LO_SLEEPABLE) != 0 && (class->lc_flags & LC_SLEEPABLE) == 0) kassert_panic("%s: lock (%s) %s can not be sleepable", __func__, class->lc_name, lock->lo_name); if ((lock->lo_flags & LO_UPGRADABLE) != 0 && (class->lc_flags & LC_UPGRADABLE) == 0) kassert_panic("%s: lock (%s) %s can not be upgradable", __func__, class->lc_name, lock->lo_name); /* * If we shouldn't watch this lock, then just clear lo_witness. * Otherwise, if witness_cold is set, then it is too early to * enroll this lock, so defer it to witness_initialize() by adding * it to the pending_locks list. If it is not too early, then enroll * the lock now. */ if (witness_watch < 1 || panicstr != NULL || (lock->lo_flags & LO_WITNESS) == 0) lock->lo_witness = NULL; else if (witness_cold) { pending_locks[pending_cnt].wh_lock = lock; pending_locks[pending_cnt++].wh_type = type; if (pending_cnt > WITNESS_PENDLIST) panic("%s: pending locks list is too small, " "increase WITNESS_PENDLIST\n", __func__); } else lock->lo_witness = enroll(type, class); } void witness_destroy(struct lock_object *lock) { struct lock_class *class; struct witness *w; class = LOCK_CLASS(lock); if (witness_cold) panic("lock (%s) %s destroyed while witness_cold", class->lc_name, lock->lo_name); /* XXX: need to verify that no one holds the lock */ if ((lock->lo_flags & LO_WITNESS) == 0 || lock->lo_witness == NULL) return; w = lock->lo_witness; mtx_lock_spin(&w_mtx); MPASS(w->w_refcount > 0); w->w_refcount--; if (w->w_refcount == 0) depart(w); mtx_unlock_spin(&w_mtx); } #ifdef DDB static void witness_ddb_compute_levels(void) { struct witness *w; /* * First clear all levels. */ STAILQ_FOREACH(w, &w_all, w_list) w->w_ddb_level = -1; /* * Look for locks with no parents and level all their descendants. */ STAILQ_FOREACH(w, &w_all, w_list) { /* If the witness has ancestors (is not a root), skip it. */ if (w->w_num_ancestors > 0) continue; witness_ddb_level_descendants(w, 0); } } static void witness_ddb_level_descendants(struct witness *w, int l) { int i; if (w->w_ddb_level >= l) return; w->w_ddb_level = l; l++; for (i = 1; i <= w_max_used_index; i++) { if (w_rmatrix[w->w_index][i] & WITNESS_PARENT) witness_ddb_level_descendants(&w_data[i], l); } } static void witness_ddb_display_descendants(int(*prnt)(const char *fmt, ...), struct witness *w, int indent) { int i; for (i = 0; i < indent; i++) prnt(" "); prnt("%s (type: %s, depth: %d, active refs: %d)", w->w_name, w->w_class->lc_name, w->w_ddb_level, w->w_refcount); if (w->w_displayed) { prnt(" -- (already displayed)\n"); return; } w->w_displayed = 1; if (w->w_file != NULL && w->w_line != 0) prnt(" -- last acquired @ %s:%d\n", fixup_filename(w->w_file), w->w_line); else prnt(" -- never acquired\n"); indent++; WITNESS_INDEX_ASSERT(w->w_index); for (i = 1; i <= w_max_used_index; i++) { if (db_pager_quit) return; if (w_rmatrix[w->w_index][i] & WITNESS_PARENT) witness_ddb_display_descendants(prnt, &w_data[i], indent); } } static void witness_ddb_display_list(int(*prnt)(const char *fmt, ...), struct witness_list *list) { struct witness *w; STAILQ_FOREACH(w, list, w_typelist) { if (w->w_file == NULL || w->w_ddb_level > 0) continue; /* This lock has no anscestors - display its descendants. */ witness_ddb_display_descendants(prnt, w, 0); if (db_pager_quit) return; } } static void witness_ddb_display(int(*prnt)(const char *fmt, ...)) { struct witness *w; KASSERT(witness_cold == 0, ("%s: witness_cold", __func__)); witness_ddb_compute_levels(); /* Clear all the displayed flags. */ STAILQ_FOREACH(w, &w_all, w_list) w->w_displayed = 0; /* * First, handle sleep locks which have been acquired at least * once. */ prnt("Sleep locks:\n"); witness_ddb_display_list(prnt, &w_sleep); if (db_pager_quit) return; /* * Now do spin locks which have been acquired at least once. */ prnt("\nSpin locks:\n"); witness_ddb_display_list(prnt, &w_spin); if (db_pager_quit) return; /* * Finally, any locks which have not been acquired yet. */ prnt("\nLocks which were never acquired:\n"); STAILQ_FOREACH(w, &w_all, w_list) { if (w->w_file != NULL || w->w_refcount == 0) continue; prnt("%s (type: %s, depth: %d)\n", w->w_name, w->w_class->lc_name, w->w_ddb_level); if (db_pager_quit) return; } } #endif /* DDB */ int witness_defineorder(struct lock_object *lock1, struct lock_object *lock2) { if (witness_watch == -1 || panicstr != NULL) return (0); /* Require locks that witness knows about. */ if (lock1 == NULL || lock1->lo_witness == NULL || lock2 == NULL || lock2->lo_witness == NULL) return (EINVAL); mtx_assert(&w_mtx, MA_NOTOWNED); mtx_lock_spin(&w_mtx); /* * If we already have either an explicit or implied lock order that * is the other way around, then return an error. */ if (witness_watch && isitmydescendant(lock2->lo_witness, lock1->lo_witness)) { mtx_unlock_spin(&w_mtx); return (EDOOFUS); } /* Try to add the new order. */ CTR3(KTR_WITNESS, "%s: adding %s as a child of %s", __func__, lock2->lo_witness->w_name, lock1->lo_witness->w_name); itismychild(lock1->lo_witness, lock2->lo_witness); mtx_unlock_spin(&w_mtx); return (0); } void witness_checkorder(struct lock_object *lock, int flags, const char *file, int line, struct lock_object *interlock) { struct lock_list_entry *lock_list, *lle; struct lock_instance *lock1, *lock2, *plock; struct lock_class *class, *iclass; struct witness *w, *w1; struct thread *td; int i, j; if (witness_cold || witness_watch < 1 || lock->lo_witness == NULL || panicstr != NULL) return; w = lock->lo_witness; class = LOCK_CLASS(lock); td = curthread; if (class->lc_flags & LC_SLEEPLOCK) { /* * Since spin locks include a critical section, this check * implicitly enforces a lock order of all sleep locks before * all spin locks. */ if (td->td_critnest != 0 && !kdb_active) kassert_panic("acquiring blockable sleep lock with " "spinlock or critical section held (%s) %s @ %s:%d", class->lc_name, lock->lo_name, fixup_filename(file), line); /* * If this is the first lock acquired then just return as * no order checking is needed. */ lock_list = td->td_sleeplocks; if (lock_list == NULL || lock_list->ll_count == 0) return; } else { /* * If this is the first lock, just return as no order * checking is needed. Avoid problems with thread * migration pinning the thread while checking if * spinlocks are held. If at least one spinlock is held * the thread is in a safe path and it is allowed to * unpin it. */ sched_pin(); lock_list = PCPU_GET(spinlocks); if (lock_list == NULL || lock_list->ll_count == 0) { sched_unpin(); return; } sched_unpin(); } /* * Check to see if we are recursing on a lock we already own. If * so, make sure that we don't mismatch exclusive and shared lock * acquires. */ lock1 = find_instance(lock_list, lock); if (lock1 != NULL) { if ((lock1->li_flags & LI_EXCLUSIVE) != 0 && (flags & LOP_EXCLUSIVE) == 0) { witness_output("shared lock of (%s) %s @ %s:%d\n", class->lc_name, lock->lo_name, fixup_filename(file), line); witness_output("while exclusively locked from %s:%d\n", fixup_filename(lock1->li_file), lock1->li_line); kassert_panic("excl->share"); } if ((lock1->li_flags & LI_EXCLUSIVE) == 0 && (flags & LOP_EXCLUSIVE) != 0) { witness_output("exclusive lock of (%s) %s @ %s:%d\n", class->lc_name, lock->lo_name, fixup_filename(file), line); witness_output("while share locked from %s:%d\n", fixup_filename(lock1->li_file), lock1->li_line); kassert_panic("share->excl"); } return; } /* Warn if the interlock is not locked exactly once. */ if (interlock != NULL) { iclass = LOCK_CLASS(interlock); lock1 = find_instance(lock_list, interlock); if (lock1 == NULL) kassert_panic("interlock (%s) %s not locked @ %s:%d", iclass->lc_name, interlock->lo_name, fixup_filename(file), line); else if ((lock1->li_flags & LI_RECURSEMASK) != 0) kassert_panic("interlock (%s) %s recursed @ %s:%d", iclass->lc_name, interlock->lo_name, fixup_filename(file), line); } /* * Find the previously acquired lock, but ignore interlocks. */ plock = &lock_list->ll_children[lock_list->ll_count - 1]; if (interlock != NULL && plock->li_lock == interlock) { if (lock_list->ll_count > 1) plock = &lock_list->ll_children[lock_list->ll_count - 2]; else { lle = lock_list->ll_next; /* * The interlock is the only lock we hold, so * simply return. */ if (lle == NULL) return; plock = &lle->ll_children[lle->ll_count - 1]; } } /* * Try to perform most checks without a lock. If this succeeds we * can skip acquiring the lock and return success. Otherwise we redo * the check with the lock held to handle races with concurrent updates. */ w1 = plock->li_lock->lo_witness; if (witness_lock_order_check(w1, w)) return; mtx_lock_spin(&w_mtx); if (witness_lock_order_check(w1, w)) { mtx_unlock_spin(&w_mtx); return; } witness_lock_order_add(w1, w); /* * Check for duplicate locks of the same type. Note that we only * have to check for this on the last lock we just acquired. Any * other cases will be caught as lock order violations. */ if (w1 == w) { i = w->w_index; if (!(lock->lo_flags & LO_DUPOK) && !(flags & LOP_DUPOK) && !(w_rmatrix[i][i] & WITNESS_REVERSAL)) { w_rmatrix[i][i] |= WITNESS_REVERSAL; w->w_reversed = 1; mtx_unlock_spin(&w_mtx); witness_output( "acquiring duplicate lock of same type: \"%s\"\n", w->w_name); witness_output(" 1st %s @ %s:%d\n", plock->li_lock->lo_name, fixup_filename(plock->li_file), plock->li_line); witness_output(" 2nd %s @ %s:%d\n", lock->lo_name, fixup_filename(file), line); witness_debugger(1, __func__); } else mtx_unlock_spin(&w_mtx); return; } mtx_assert(&w_mtx, MA_OWNED); /* * If we know that the lock we are acquiring comes after * the lock we most recently acquired in the lock order tree, * then there is no need for any further checks. */ if (isitmychild(w1, w)) goto out; for (j = 0, lle = lock_list; lle != NULL; lle = lle->ll_next) { for (i = lle->ll_count - 1; i >= 0; i--, j++) { MPASS(j < LOCK_CHILDCOUNT * LOCK_NCHILDREN); lock1 = &lle->ll_children[i]; /* * Ignore the interlock. */ if (interlock == lock1->li_lock) continue; /* * If this lock doesn't undergo witness checking, * then skip it. */ w1 = lock1->li_lock->lo_witness; if (w1 == NULL) { KASSERT((lock1->li_lock->lo_flags & LO_WITNESS) == 0, ("lock missing witness structure")); continue; } /* * If we are locking Giant and this is a sleepable * lock, then skip it. */ if ((lock1->li_lock->lo_flags & LO_SLEEPABLE) != 0 && lock == &Giant.lock_object) continue; /* * If we are locking a sleepable lock and this lock * is Giant, then skip it. */ if ((lock->lo_flags & LO_SLEEPABLE) != 0 && lock1->li_lock == &Giant.lock_object) continue; /* * If we are locking a sleepable lock and this lock * isn't sleepable, we want to treat it as a lock * order violation to enfore a general lock order of * sleepable locks before non-sleepable locks. */ if (((lock->lo_flags & LO_SLEEPABLE) != 0 && (lock1->li_lock->lo_flags & LO_SLEEPABLE) == 0)) goto reversal; /* * If we are locking Giant and this is a non-sleepable * lock, then treat it as a reversal. */ if ((lock1->li_lock->lo_flags & LO_SLEEPABLE) == 0 && lock == &Giant.lock_object) goto reversal; /* * Check the lock order hierarchy for a reveresal. */ if (!isitmydescendant(w, w1)) continue; reversal: /* * We have a lock order violation, check to see if it * is allowed or has already been yelled about. */ #ifdef BLESSING /* * If the lock order is blessed, just bail. We don't * look for other lock order violations though, which * may be a bug. */ if (blessed(w, w1)) goto out; #endif /* Bail if this violation is known */ if (w_rmatrix[w1->w_index][w->w_index] & WITNESS_REVERSAL) goto out; /* Record this as a violation */ w_rmatrix[w1->w_index][w->w_index] |= WITNESS_REVERSAL; w_rmatrix[w->w_index][w1->w_index] |= WITNESS_REVERSAL; w->w_reversed = w1->w_reversed = 1; witness_increment_graph_generation(); mtx_unlock_spin(&w_mtx); #ifdef WITNESS_NO_VNODE /* * There are known LORs between VNODE locks. They are * not an indication of a bug. VNODE locks are flagged * as such (LO_IS_VNODE) and we don't yell if the LOR * is between 2 VNODE locks. */ if ((lock->lo_flags & LO_IS_VNODE) != 0 && (lock1->li_lock->lo_flags & LO_IS_VNODE) != 0) return; #endif /* * Ok, yell about it. */ if (((lock->lo_flags & LO_SLEEPABLE) != 0 && (lock1->li_lock->lo_flags & LO_SLEEPABLE) == 0)) witness_output( "lock order reversal: (sleepable after non-sleepable)\n"); else if ((lock1->li_lock->lo_flags & LO_SLEEPABLE) == 0 && lock == &Giant.lock_object) witness_output( "lock order reversal: (Giant after non-sleepable)\n"); else witness_output("lock order reversal:\n"); /* * Try to locate an earlier lock with * witness w in our list. */ do { lock2 = &lle->ll_children[i]; MPASS(lock2->li_lock != NULL); if (lock2->li_lock->lo_witness == w) break; if (i == 0 && lle->ll_next != NULL) { lle = lle->ll_next; i = lle->ll_count - 1; MPASS(i >= 0 && i < LOCK_NCHILDREN); } else i--; } while (i >= 0); if (i < 0) { witness_output(" 1st %p %s (%s) @ %s:%d\n", lock1->li_lock, lock1->li_lock->lo_name, w1->w_name, fixup_filename(lock1->li_file), lock1->li_line); witness_output(" 2nd %p %s (%s) @ %s:%d\n", lock, lock->lo_name, w->w_name, fixup_filename(file), line); } else { witness_output(" 1st %p %s (%s) @ %s:%d\n", lock2->li_lock, lock2->li_lock->lo_name, lock2->li_lock->lo_witness->w_name, fixup_filename(lock2->li_file), lock2->li_line); witness_output(" 2nd %p %s (%s) @ %s:%d\n", lock1->li_lock, lock1->li_lock->lo_name, w1->w_name, fixup_filename(lock1->li_file), lock1->li_line); witness_output(" 3rd %p %s (%s) @ %s:%d\n", lock, lock->lo_name, w->w_name, fixup_filename(file), line); } witness_debugger(1, __func__); return; } } /* * If requested, build a new lock order. However, don't build a new * relationship between a sleepable lock and Giant if it is in the * wrong direction. The correct lock order is that sleepable locks * always come before Giant. */ if (flags & LOP_NEWORDER && !(plock->li_lock == &Giant.lock_object && (lock->lo_flags & LO_SLEEPABLE) != 0)) { CTR3(KTR_WITNESS, "%s: adding %s as a child of %s", __func__, w->w_name, plock->li_lock->lo_witness->w_name); itismychild(plock->li_lock->lo_witness, w); } out: mtx_unlock_spin(&w_mtx); } void witness_lock(struct lock_object *lock, int flags, const char *file, int line) { struct lock_list_entry **lock_list, *lle; struct lock_instance *instance; struct witness *w; struct thread *td; if (witness_cold || witness_watch == -1 || lock->lo_witness == NULL || panicstr != NULL) return; w = lock->lo_witness; td = curthread; /* Determine lock list for this lock. */ if (LOCK_CLASS(lock)->lc_flags & LC_SLEEPLOCK) lock_list = &td->td_sleeplocks; else lock_list = PCPU_PTR(spinlocks); /* Check to see if we are recursing on a lock we already own. */ instance = find_instance(*lock_list, lock); if (instance != NULL) { instance->li_flags++; CTR4(KTR_WITNESS, "%s: pid %d recursed on %s r=%d", __func__, td->td_proc->p_pid, lock->lo_name, instance->li_flags & LI_RECURSEMASK); instance->li_file = file; instance->li_line = line; return; } /* Update per-witness last file and line acquire. */ w->w_file = file; w->w_line = line; /* Find the next open lock instance in the list and fill it. */ lle = *lock_list; if (lle == NULL || lle->ll_count == LOCK_NCHILDREN) { lle = witness_lock_list_get(); if (lle == NULL) return; lle->ll_next = *lock_list; CTR3(KTR_WITNESS, "%s: pid %d added lle %p", __func__, td->td_proc->p_pid, lle); *lock_list = lle; } instance = &lle->ll_children[lle->ll_count++]; instance->li_lock = lock; instance->li_line = line; instance->li_file = file; if ((flags & LOP_EXCLUSIVE) != 0) instance->li_flags = LI_EXCLUSIVE; else instance->li_flags = 0; CTR4(KTR_WITNESS, "%s: pid %d added %s as lle[%d]", __func__, td->td_proc->p_pid, lock->lo_name, lle->ll_count - 1); } void witness_upgrade(struct lock_object *lock, int flags, const char *file, int line) { struct lock_instance *instance; struct lock_class *class; KASSERT(witness_cold == 0, ("%s: witness_cold", __func__)); if (lock->lo_witness == NULL || witness_watch == -1 || panicstr != NULL) return; class = LOCK_CLASS(lock); if (witness_watch) { if ((lock->lo_flags & LO_UPGRADABLE) == 0) kassert_panic( "upgrade of non-upgradable lock (%s) %s @ %s:%d", class->lc_name, lock->lo_name, fixup_filename(file), line); if ((class->lc_flags & LC_SLEEPLOCK) == 0) kassert_panic( "upgrade of non-sleep lock (%s) %s @ %s:%d", class->lc_name, lock->lo_name, fixup_filename(file), line); } instance = find_instance(curthread->td_sleeplocks, lock); if (instance == NULL) { kassert_panic("upgrade of unlocked lock (%s) %s @ %s:%d", class->lc_name, lock->lo_name, fixup_filename(file), line); return; } if (witness_watch) { if ((instance->li_flags & LI_EXCLUSIVE) != 0) kassert_panic( "upgrade of exclusive lock (%s) %s @ %s:%d", class->lc_name, lock->lo_name, fixup_filename(file), line); if ((instance->li_flags & LI_RECURSEMASK) != 0) kassert_panic( "upgrade of recursed lock (%s) %s r=%d @ %s:%d", class->lc_name, lock->lo_name, instance->li_flags & LI_RECURSEMASK, fixup_filename(file), line); } instance->li_flags |= LI_EXCLUSIVE; } void witness_downgrade(struct lock_object *lock, int flags, const char *file, int line) { struct lock_instance *instance; struct lock_class *class; KASSERT(witness_cold == 0, ("%s: witness_cold", __func__)); if (lock->lo_witness == NULL || witness_watch == -1 || panicstr != NULL) return; class = LOCK_CLASS(lock); if (witness_watch) { if ((lock->lo_flags & LO_UPGRADABLE) == 0) kassert_panic( "downgrade of non-upgradable lock (%s) %s @ %s:%d", class->lc_name, lock->lo_name, fixup_filename(file), line); if ((class->lc_flags & LC_SLEEPLOCK) == 0) kassert_panic( "downgrade of non-sleep lock (%s) %s @ %s:%d", class->lc_name, lock->lo_name, fixup_filename(file), line); } instance = find_instance(curthread->td_sleeplocks, lock); if (instance == NULL) { kassert_panic("downgrade of unlocked lock (%s) %s @ %s:%d", class->lc_name, lock->lo_name, fixup_filename(file), line); return; } if (witness_watch) { if ((instance->li_flags & LI_EXCLUSIVE) == 0) kassert_panic( "downgrade of shared lock (%s) %s @ %s:%d", class->lc_name, lock->lo_name, fixup_filename(file), line); if ((instance->li_flags & LI_RECURSEMASK) != 0) kassert_panic( "downgrade of recursed lock (%s) %s r=%d @ %s:%d", class->lc_name, lock->lo_name, instance->li_flags & LI_RECURSEMASK, fixup_filename(file), line); } instance->li_flags &= ~LI_EXCLUSIVE; } void witness_unlock(struct lock_object *lock, int flags, const char *file, int line) { struct lock_list_entry **lock_list, *lle; struct lock_instance *instance; struct lock_class *class; struct thread *td; register_t s; int i, j; if (witness_cold || lock->lo_witness == NULL || panicstr != NULL) return; td = curthread; class = LOCK_CLASS(lock); /* Find lock instance associated with this lock. */ if (class->lc_flags & LC_SLEEPLOCK) lock_list = &td->td_sleeplocks; else lock_list = PCPU_PTR(spinlocks); lle = *lock_list; for (; *lock_list != NULL; lock_list = &(*lock_list)->ll_next) for (i = 0; i < (*lock_list)->ll_count; i++) { instance = &(*lock_list)->ll_children[i]; if (instance->li_lock == lock) goto found; } /* * When disabling WITNESS through witness_watch we could end up in * having registered locks in the td_sleeplocks queue. * We have to make sure we flush these queues, so just search for * eventual register locks and remove them. */ if (witness_watch > 0) { kassert_panic("lock (%s) %s not locked @ %s:%d", class->lc_name, lock->lo_name, fixup_filename(file), line); return; } else { return; } found: /* First, check for shared/exclusive mismatches. */ if ((instance->li_flags & LI_EXCLUSIVE) != 0 && witness_watch > 0 && (flags & LOP_EXCLUSIVE) == 0) { witness_output("shared unlock of (%s) %s @ %s:%d\n", class->lc_name, lock->lo_name, fixup_filename(file), line); witness_output("while exclusively locked from %s:%d\n", fixup_filename(instance->li_file), instance->li_line); kassert_panic("excl->ushare"); } if ((instance->li_flags & LI_EXCLUSIVE) == 0 && witness_watch > 0 && (flags & LOP_EXCLUSIVE) != 0) { witness_output("exclusive unlock of (%s) %s @ %s:%d\n", class->lc_name, lock->lo_name, fixup_filename(file), line); witness_output("while share locked from %s:%d\n", fixup_filename(instance->li_file), instance->li_line); kassert_panic("share->uexcl"); } /* If we are recursed, unrecurse. */ if ((instance->li_flags & LI_RECURSEMASK) > 0) { CTR4(KTR_WITNESS, "%s: pid %d unrecursed on %s r=%d", __func__, td->td_proc->p_pid, instance->li_lock->lo_name, instance->li_flags); instance->li_flags--; return; } /* The lock is now being dropped, check for NORELEASE flag */ if ((instance->li_flags & LI_NORELEASE) != 0 && witness_watch > 0) { witness_output("forbidden unlock of (%s) %s @ %s:%d\n", class->lc_name, lock->lo_name, fixup_filename(file), line); kassert_panic("lock marked norelease"); } /* Otherwise, remove this item from the list. */ s = intr_disable(); CTR4(KTR_WITNESS, "%s: pid %d removed %s from lle[%d]", __func__, td->td_proc->p_pid, instance->li_lock->lo_name, (*lock_list)->ll_count - 1); for (j = i; j < (*lock_list)->ll_count - 1; j++) (*lock_list)->ll_children[j] = (*lock_list)->ll_children[j + 1]; (*lock_list)->ll_count--; intr_restore(s); /* * In order to reduce contention on w_mtx, we want to keep always an * head object into lists so that frequent allocation from the * free witness pool (and subsequent locking) is avoided. * In order to maintain the current code simple, when the head * object is totally unloaded it means also that we do not have * further objects in the list, so the list ownership needs to be * hand over to another object if the current head needs to be freed. */ if ((*lock_list)->ll_count == 0) { if (*lock_list == lle) { if (lle->ll_next == NULL) return; } else lle = *lock_list; *lock_list = lle->ll_next; CTR3(KTR_WITNESS, "%s: pid %d removed lle %p", __func__, td->td_proc->p_pid, lle); witness_lock_list_free(lle); } } void witness_thread_exit(struct thread *td) { struct lock_list_entry *lle; int i, n; lle = td->td_sleeplocks; if (lle == NULL || panicstr != NULL) return; if (lle->ll_count != 0) { for (n = 0; lle != NULL; lle = lle->ll_next) for (i = lle->ll_count - 1; i >= 0; i--) { if (n == 0) witness_output( "Thread %p exiting with the following locks held:\n", td); n++; witness_list_lock(&lle->ll_children[i], witness_output); } kassert_panic( "Thread %p cannot exit while holding sleeplocks\n", td); } witness_lock_list_free(lle); } /* * Warn if any locks other than 'lock' are held. Flags can be passed in to * exempt Giant and sleepable locks from the checks as well. If any * non-exempt locks are held, then a supplied message is printed to the * output channel along with a list of the offending locks. If indicated in the * flags then a failure results in a panic as well. */ int witness_warn(int flags, struct lock_object *lock, const char *fmt, ...) { struct lock_list_entry *lock_list, *lle; struct lock_instance *lock1; struct thread *td; va_list ap; int i, n; if (witness_cold || witness_watch < 1 || panicstr != NULL) return (0); n = 0; td = curthread; for (lle = td->td_sleeplocks; lle != NULL; lle = lle->ll_next) for (i = lle->ll_count - 1; i >= 0; i--) { lock1 = &lle->ll_children[i]; if (lock1->li_lock == lock) continue; if (flags & WARN_GIANTOK && lock1->li_lock == &Giant.lock_object) continue; if (flags & WARN_SLEEPOK && (lock1->li_lock->lo_flags & LO_SLEEPABLE) != 0) continue; if (n == 0) { va_start(ap, fmt); vprintf(fmt, ap); va_end(ap); printf(" with the following %slocks held:\n", (flags & WARN_SLEEPOK) != 0 ? "non-sleepable " : ""); } n++; witness_list_lock(lock1, printf); } /* * Pin the thread in order to avoid problems with thread migration. * Once that all verifies are passed about spinlocks ownership, * the thread is in a safe path and it can be unpinned. */ sched_pin(); lock_list = PCPU_GET(spinlocks); if (lock_list != NULL && lock_list->ll_count != 0) { sched_unpin(); /* * We should only have one spinlock and as long as * the flags cannot match for this locks class, * check if the first spinlock is the one curthread * should hold. */ lock1 = &lock_list->ll_children[lock_list->ll_count - 1]; if (lock_list->ll_count == 1 && lock_list->ll_next == NULL && lock1->li_lock == lock && n == 0) return (0); va_start(ap, fmt); vprintf(fmt, ap); va_end(ap); printf(" with the following %slocks held:\n", (flags & WARN_SLEEPOK) != 0 ? "non-sleepable " : ""); n += witness_list_locks(&lock_list, printf); } else sched_unpin(); if (flags & WARN_PANIC && n) kassert_panic("%s", __func__); else witness_debugger(n, __func__); return (n); } const char * witness_file(struct lock_object *lock) { struct witness *w; if (witness_cold || witness_watch < 1 || lock->lo_witness == NULL) return ("?"); w = lock->lo_witness; return (w->w_file); } int witness_line(struct lock_object *lock) { struct witness *w; if (witness_cold || witness_watch < 1 || lock->lo_witness == NULL) return (0); w = lock->lo_witness; return (w->w_line); } static struct witness * enroll(const char *description, struct lock_class *lock_class) { struct witness *w; MPASS(description != NULL); if (witness_watch == -1 || panicstr != NULL) return (NULL); if ((lock_class->lc_flags & LC_SPINLOCK)) { if (witness_skipspin) return (NULL); } else if ((lock_class->lc_flags & LC_SLEEPLOCK) == 0) { kassert_panic("lock class %s is not sleep or spin", lock_class->lc_name); return (NULL); } mtx_lock_spin(&w_mtx); w = witness_hash_get(description); if (w) goto found; if ((w = witness_get()) == NULL) return (NULL); MPASS(strlen(description) < MAX_W_NAME); strcpy(w->w_name, description); w->w_class = lock_class; w->w_refcount = 1; STAILQ_INSERT_HEAD(&w_all, w, w_list); if (lock_class->lc_flags & LC_SPINLOCK) { STAILQ_INSERT_HEAD(&w_spin, w, w_typelist); w_spin_cnt++; } else if (lock_class->lc_flags & LC_SLEEPLOCK) { STAILQ_INSERT_HEAD(&w_sleep, w, w_typelist); w_sleep_cnt++; } /* Insert new witness into the hash */ witness_hash_put(w); witness_increment_graph_generation(); mtx_unlock_spin(&w_mtx); return (w); found: w->w_refcount++; if (w->w_refcount == 1) w->w_class = lock_class; mtx_unlock_spin(&w_mtx); if (lock_class != w->w_class) kassert_panic( "lock (%s) %s does not match earlier (%s) lock", description, lock_class->lc_name, w->w_class->lc_name); return (w); } static void depart(struct witness *w) { MPASS(w->w_refcount == 0); if (w->w_class->lc_flags & LC_SLEEPLOCK) { w_sleep_cnt--; } else { w_spin_cnt--; } /* * Set file to NULL as it may point into a loadable module. */ w->w_file = NULL; w->w_line = 0; witness_increment_graph_generation(); } static void adopt(struct witness *parent, struct witness *child) { int pi, ci, i, j; if (witness_cold == 0) mtx_assert(&w_mtx, MA_OWNED); /* If the relationship is already known, there's no work to be done. */ if (isitmychild(parent, child)) return; /* When the structure of the graph changes, bump up the generation. */ witness_increment_graph_generation(); /* * The hard part ... create the direct relationship, then propagate all * indirect relationships. */ pi = parent->w_index; ci = child->w_index; WITNESS_INDEX_ASSERT(pi); WITNESS_INDEX_ASSERT(ci); MPASS(pi != ci); w_rmatrix[pi][ci] |= WITNESS_PARENT; w_rmatrix[ci][pi] |= WITNESS_CHILD; /* * If parent was not already an ancestor of child, * then we increment the descendant and ancestor counters. */ if ((w_rmatrix[pi][ci] & WITNESS_ANCESTOR) == 0) { parent->w_num_descendants++; child->w_num_ancestors++; } /* * Find each ancestor of 'pi'. Note that 'pi' itself is counted as * an ancestor of 'pi' during this loop. */ for (i = 1; i <= w_max_used_index; i++) { if ((w_rmatrix[i][pi] & WITNESS_ANCESTOR_MASK) == 0 && (i != pi)) continue; /* Find each descendant of 'i' and mark it as a descendant. */ for (j = 1; j <= w_max_used_index; j++) { /* * Skip children that are already marked as * descendants of 'i'. */ if (w_rmatrix[i][j] & WITNESS_ANCESTOR_MASK) continue; /* * We are only interested in descendants of 'ci'. Note * that 'ci' itself is counted as a descendant of 'ci'. */ if ((w_rmatrix[ci][j] & WITNESS_ANCESTOR_MASK) == 0 && (j != ci)) continue; w_rmatrix[i][j] |= WITNESS_ANCESTOR; w_rmatrix[j][i] |= WITNESS_DESCENDANT; w_data[i].w_num_descendants++; w_data[j].w_num_ancestors++; /* * Make sure we aren't marking a node as both an * ancestor and descendant. We should have caught * this as a lock order reversal earlier. */ if ((w_rmatrix[i][j] & WITNESS_ANCESTOR_MASK) && (w_rmatrix[i][j] & WITNESS_DESCENDANT_MASK)) { printf("witness rmatrix paradox! [%d][%d]=%d " "both ancestor and descendant\n", i, j, w_rmatrix[i][j]); kdb_backtrace(); printf("Witness disabled.\n"); witness_watch = -1; } if ((w_rmatrix[j][i] & WITNESS_ANCESTOR_MASK) && (w_rmatrix[j][i] & WITNESS_DESCENDANT_MASK)) { printf("witness rmatrix paradox! [%d][%d]=%d " "both ancestor and descendant\n", j, i, w_rmatrix[j][i]); kdb_backtrace(); printf("Witness disabled.\n"); witness_watch = -1; } } } } static void itismychild(struct witness *parent, struct witness *child) { int unlocked; MPASS(child != NULL && parent != NULL); if (witness_cold == 0) mtx_assert(&w_mtx, MA_OWNED); if (!witness_lock_type_equal(parent, child)) { if (witness_cold == 0) { unlocked = 1; mtx_unlock_spin(&w_mtx); } else { unlocked = 0; } kassert_panic( "%s: parent \"%s\" (%s) and child \"%s\" (%s) are not " "the same lock type", __func__, parent->w_name, parent->w_class->lc_name, child->w_name, child->w_class->lc_name); if (unlocked) mtx_lock_spin(&w_mtx); } adopt(parent, child); } /* * Generic code for the isitmy*() functions. The rmask parameter is the * expected relationship of w1 to w2. */ static int _isitmyx(struct witness *w1, struct witness *w2, int rmask, const char *fname) { unsigned char r1, r2; int i1, i2; i1 = w1->w_index; i2 = w2->w_index; WITNESS_INDEX_ASSERT(i1); WITNESS_INDEX_ASSERT(i2); r1 = w_rmatrix[i1][i2] & WITNESS_RELATED_MASK; r2 = w_rmatrix[i2][i1] & WITNESS_RELATED_MASK; /* The flags on one better be the inverse of the flags on the other */ if (!((WITNESS_ATOD(r1) == r2 && WITNESS_DTOA(r2) == r1) || (WITNESS_DTOA(r1) == r2 && WITNESS_ATOD(r2) == r1))) { /* Don't squawk if we're potentially racing with an update. */ if (!mtx_owned(&w_mtx)) return (0); printf("%s: rmatrix mismatch between %s (index %d) and %s " "(index %d): w_rmatrix[%d][%d] == %hhx but " "w_rmatrix[%d][%d] == %hhx\n", fname, w1->w_name, i1, w2->w_name, i2, i1, i2, r1, i2, i1, r2); kdb_backtrace(); printf("Witness disabled.\n"); witness_watch = -1; } return (r1 & rmask); } /* * Checks if @child is a direct child of @parent. */ static int isitmychild(struct witness *parent, struct witness *child) { return (_isitmyx(parent, child, WITNESS_PARENT, __func__)); } /* * Checks if @descendant is a direct or inderect descendant of @ancestor. */ static int isitmydescendant(struct witness *ancestor, struct witness *descendant) { return (_isitmyx(ancestor, descendant, WITNESS_ANCESTOR_MASK, __func__)); } #ifdef BLESSING static int blessed(struct witness *w1, struct witness *w2) { int i; struct witness_blessed *b; for (i = 0; i < nitems(blessed_list); i++) { b = &blessed_list[i]; if (strcmp(w1->w_name, b->b_lock1) == 0) { if (strcmp(w2->w_name, b->b_lock2) == 0) return (1); continue; } if (strcmp(w1->w_name, b->b_lock2) == 0) if (strcmp(w2->w_name, b->b_lock1) == 0) return (1); } return (0); } #endif static struct witness * witness_get(void) { struct witness *w; int index; if (witness_cold == 0) mtx_assert(&w_mtx, MA_OWNED); if (witness_watch == -1) { mtx_unlock_spin(&w_mtx); return (NULL); } if (STAILQ_EMPTY(&w_free)) { witness_watch = -1; mtx_unlock_spin(&w_mtx); printf("WITNESS: unable to allocate a new witness object\n"); return (NULL); } w = STAILQ_FIRST(&w_free); STAILQ_REMOVE_HEAD(&w_free, w_list); w_free_cnt--; index = w->w_index; MPASS(index > 0 && index == w_max_used_index+1 && index < witness_count); bzero(w, sizeof(*w)); w->w_index = index; if (index > w_max_used_index) w_max_used_index = index; return (w); } static void witness_free(struct witness *w) { STAILQ_INSERT_HEAD(&w_free, w, w_list); w_free_cnt++; } static struct lock_list_entry * witness_lock_list_get(void) { struct lock_list_entry *lle; if (witness_watch == -1) return (NULL); mtx_lock_spin(&w_mtx); lle = w_lock_list_free; if (lle == NULL) { witness_watch = -1; mtx_unlock_spin(&w_mtx); printf("%s: witness exhausted\n", __func__); return (NULL); } w_lock_list_free = lle->ll_next; mtx_unlock_spin(&w_mtx); bzero(lle, sizeof(*lle)); return (lle); } static void witness_lock_list_free(struct lock_list_entry *lle) { mtx_lock_spin(&w_mtx); lle->ll_next = w_lock_list_free; w_lock_list_free = lle; mtx_unlock_spin(&w_mtx); } static struct lock_instance * find_instance(struct lock_list_entry *list, const struct lock_object *lock) { struct lock_list_entry *lle; struct lock_instance *instance; int i; for (lle = list; lle != NULL; lle = lle->ll_next) for (i = lle->ll_count - 1; i >= 0; i--) { instance = &lle->ll_children[i]; if (instance->li_lock == lock) return (instance); } return (NULL); } static void witness_list_lock(struct lock_instance *instance, int (*prnt)(const char *fmt, ...)) { struct lock_object *lock; lock = instance->li_lock; prnt("%s %s %s", (instance->li_flags & LI_EXCLUSIVE) != 0 ? "exclusive" : "shared", LOCK_CLASS(lock)->lc_name, lock->lo_name); if (lock->lo_witness->w_name != lock->lo_name) prnt(" (%s)", lock->lo_witness->w_name); prnt(" r = %d (%p) locked @ %s:%d\n", instance->li_flags & LI_RECURSEMASK, lock, fixup_filename(instance->li_file), instance->li_line); } static int witness_output(const char *fmt, ...) { va_list ap; int ret; va_start(ap, fmt); ret = witness_voutput(fmt, ap); va_end(ap); return (ret); } static int witness_voutput(const char *fmt, va_list ap) { int ret; ret = 0; switch (witness_channel) { case WITNESS_CONSOLE: ret = vprintf(fmt, ap); break; case WITNESS_LOG: vlog(LOG_NOTICE, fmt, ap); break; case WITNESS_NONE: break; } return (ret); } #ifdef DDB static int witness_thread_has_locks(struct thread *td) { if (td->td_sleeplocks == NULL) return (0); return (td->td_sleeplocks->ll_count != 0); } static int witness_proc_has_locks(struct proc *p) { struct thread *td; FOREACH_THREAD_IN_PROC(p, td) { if (witness_thread_has_locks(td)) return (1); } return (0); } #endif int witness_list_locks(struct lock_list_entry **lock_list, int (*prnt)(const char *fmt, ...)) { struct lock_list_entry *lle; int i, nheld; nheld = 0; for (lle = *lock_list; lle != NULL; lle = lle->ll_next) for (i = lle->ll_count - 1; i >= 0; i--) { witness_list_lock(&lle->ll_children[i], prnt); nheld++; } return (nheld); } /* * This is a bit risky at best. We call this function when we have timed * out acquiring a spin lock, and we assume that the other CPU is stuck * with this lock held. So, we go groveling around in the other CPU's * per-cpu data to try to find the lock instance for this spin lock to * see when it was last acquired. */ void witness_display_spinlock(struct lock_object *lock, struct thread *owner, int (*prnt)(const char *fmt, ...)) { struct lock_instance *instance; struct pcpu *pc; if (owner->td_critnest == 0 || owner->td_oncpu == NOCPU) return; pc = pcpu_find(owner->td_oncpu); instance = find_instance(pc->pc_spinlocks, lock); if (instance != NULL) witness_list_lock(instance, prnt); } void witness_save(struct lock_object *lock, const char **filep, int *linep) { struct lock_list_entry *lock_list; struct lock_instance *instance; struct lock_class *class; /* * This function is used independently in locking code to deal with * Giant, SCHEDULER_STOPPED() check can be removed here after Giant * is gone. */ if (SCHEDULER_STOPPED()) return; KASSERT(witness_cold == 0, ("%s: witness_cold", __func__)); if (lock->lo_witness == NULL || witness_watch == -1 || panicstr != NULL) return; class = LOCK_CLASS(lock); if (class->lc_flags & LC_SLEEPLOCK) lock_list = curthread->td_sleeplocks; else { if (witness_skipspin) return; lock_list = PCPU_GET(spinlocks); } instance = find_instance(lock_list, lock); if (instance == NULL) { kassert_panic("%s: lock (%s) %s not locked", __func__, class->lc_name, lock->lo_name); return; } *filep = instance->li_file; *linep = instance->li_line; } void witness_restore(struct lock_object *lock, const char *file, int line) { struct lock_list_entry *lock_list; struct lock_instance *instance; struct lock_class *class; /* * This function is used independently in locking code to deal with * Giant, SCHEDULER_STOPPED() check can be removed here after Giant * is gone. */ if (SCHEDULER_STOPPED()) return; KASSERT(witness_cold == 0, ("%s: witness_cold", __func__)); if (lock->lo_witness == NULL || witness_watch == -1 || panicstr != NULL) return; class = LOCK_CLASS(lock); if (class->lc_flags & LC_SLEEPLOCK) lock_list = curthread->td_sleeplocks; else { if (witness_skipspin) return; lock_list = PCPU_GET(spinlocks); } instance = find_instance(lock_list, lock); if (instance == NULL) kassert_panic("%s: lock (%s) %s not locked", __func__, class->lc_name, lock->lo_name); lock->lo_witness->w_file = file; lock->lo_witness->w_line = line; if (instance == NULL) return; instance->li_file = file; instance->li_line = line; } void witness_assert(const struct lock_object *lock, int flags, const char *file, int line) { #ifdef INVARIANT_SUPPORT struct lock_instance *instance; struct lock_class *class; if (lock->lo_witness == NULL || witness_watch < 1 || panicstr != NULL) return; class = LOCK_CLASS(lock); if ((class->lc_flags & LC_SLEEPLOCK) != 0) instance = find_instance(curthread->td_sleeplocks, lock); else if ((class->lc_flags & LC_SPINLOCK) != 0) instance = find_instance(PCPU_GET(spinlocks), lock); else { kassert_panic("Lock (%s) %s is not sleep or spin!", class->lc_name, lock->lo_name); return; } switch (flags) { case LA_UNLOCKED: if (instance != NULL) kassert_panic("Lock (%s) %s locked @ %s:%d.", class->lc_name, lock->lo_name, fixup_filename(file), line); break; case LA_LOCKED: case LA_LOCKED | LA_RECURSED: case LA_LOCKED | LA_NOTRECURSED: case LA_SLOCKED: case LA_SLOCKED | LA_RECURSED: case LA_SLOCKED | LA_NOTRECURSED: case LA_XLOCKED: case LA_XLOCKED | LA_RECURSED: case LA_XLOCKED | LA_NOTRECURSED: if (instance == NULL) { kassert_panic("Lock (%s) %s not locked @ %s:%d.", class->lc_name, lock->lo_name, fixup_filename(file), line); break; } if ((flags & LA_XLOCKED) != 0 && (instance->li_flags & LI_EXCLUSIVE) == 0) kassert_panic( "Lock (%s) %s not exclusively locked @ %s:%d.", class->lc_name, lock->lo_name, fixup_filename(file), line); if ((flags & LA_SLOCKED) != 0 && (instance->li_flags & LI_EXCLUSIVE) != 0) kassert_panic( "Lock (%s) %s exclusively locked @ %s:%d.", class->lc_name, lock->lo_name, fixup_filename(file), line); if ((flags & LA_RECURSED) != 0 && (instance->li_flags & LI_RECURSEMASK) == 0) kassert_panic("Lock (%s) %s not recursed @ %s:%d.", class->lc_name, lock->lo_name, fixup_filename(file), line); if ((flags & LA_NOTRECURSED) != 0 && (instance->li_flags & LI_RECURSEMASK) != 0) kassert_panic("Lock (%s) %s recursed @ %s:%d.", class->lc_name, lock->lo_name, fixup_filename(file), line); break; default: kassert_panic("Invalid lock assertion at %s:%d.", fixup_filename(file), line); } #endif /* INVARIANT_SUPPORT */ } static void witness_setflag(struct lock_object *lock, int flag, int set) { struct lock_list_entry *lock_list; struct lock_instance *instance; struct lock_class *class; if (lock->lo_witness == NULL || witness_watch == -1 || panicstr != NULL) return; class = LOCK_CLASS(lock); if (class->lc_flags & LC_SLEEPLOCK) lock_list = curthread->td_sleeplocks; else { if (witness_skipspin) return; lock_list = PCPU_GET(spinlocks); } instance = find_instance(lock_list, lock); if (instance == NULL) { kassert_panic("%s: lock (%s) %s not locked", __func__, class->lc_name, lock->lo_name); return; } if (set) instance->li_flags |= flag; else instance->li_flags &= ~flag; } void witness_norelease(struct lock_object *lock) { witness_setflag(lock, LI_NORELEASE, 1); } void witness_releaseok(struct lock_object *lock) { witness_setflag(lock, LI_NORELEASE, 0); } #ifdef DDB static void witness_ddb_list(struct thread *td) { KASSERT(witness_cold == 0, ("%s: witness_cold", __func__)); KASSERT(kdb_active, ("%s: not in the debugger", __func__)); if (witness_watch < 1) return; witness_list_locks(&td->td_sleeplocks, db_printf); /* * We only handle spinlocks if td == curthread. This is somewhat broken * if td is currently executing on some other CPU and holds spin locks * as we won't display those locks. If we had a MI way of getting * the per-cpu data for a given cpu then we could use * td->td_oncpu to get the list of spinlocks for this thread * and "fix" this. * * That still wouldn't really fix this unless we locked the scheduler * lock or stopped the other CPU to make sure it wasn't changing the * list out from under us. It is probably best to just not try to * handle threads on other CPU's for now. */ if (td == curthread && PCPU_GET(spinlocks) != NULL) witness_list_locks(PCPU_PTR(spinlocks), db_printf); } DB_SHOW_COMMAND(locks, db_witness_list) { struct thread *td; if (have_addr) td = db_lookup_thread(addr, true); else td = kdb_thread; witness_ddb_list(td); } DB_SHOW_ALL_COMMAND(locks, db_witness_list_all) { struct thread *td; struct proc *p; /* * It would be nice to list only threads and processes that actually * held sleep locks, but that information is currently not exported * by WITNESS. */ FOREACH_PROC_IN_SYSTEM(p) { if (!witness_proc_has_locks(p)) continue; FOREACH_THREAD_IN_PROC(p, td) { if (!witness_thread_has_locks(td)) continue; db_printf("Process %d (%s) thread %p (%d)\n", p->p_pid, p->p_comm, td, td->td_tid); witness_ddb_list(td); if (db_pager_quit) return; } } } DB_SHOW_ALIAS(alllocks, db_witness_list_all) DB_SHOW_COMMAND(witness, db_witness_display) { witness_ddb_display(db_printf); } #endif static void sbuf_print_witness_badstacks(struct sbuf *sb, size_t *oldidx) { struct witness_lock_order_data *data1, *data2, *tmp_data1, *tmp_data2; struct witness *tmp_w1, *tmp_w2, *w1, *w2; int generation, i, j; tmp_data1 = NULL; tmp_data2 = NULL; tmp_w1 = NULL; tmp_w2 = NULL; /* Allocate and init temporary storage space. */ tmp_w1 = malloc(sizeof(struct witness), M_TEMP, M_WAITOK | M_ZERO); tmp_w2 = malloc(sizeof(struct witness), M_TEMP, M_WAITOK | M_ZERO); tmp_data1 = malloc(sizeof(struct witness_lock_order_data), M_TEMP, M_WAITOK | M_ZERO); tmp_data2 = malloc(sizeof(struct witness_lock_order_data), M_TEMP, M_WAITOK | M_ZERO); stack_zero(&tmp_data1->wlod_stack); stack_zero(&tmp_data2->wlod_stack); restart: mtx_lock_spin(&w_mtx); generation = w_generation; mtx_unlock_spin(&w_mtx); sbuf_printf(sb, "Number of known direct relationships is %d\n", w_lohash.wloh_count); for (i = 1; i < w_max_used_index; i++) { mtx_lock_spin(&w_mtx); if (generation != w_generation) { mtx_unlock_spin(&w_mtx); /* The graph has changed, try again. */ *oldidx = 0; sbuf_clear(sb); goto restart; } w1 = &w_data[i]; if (w1->w_reversed == 0) { mtx_unlock_spin(&w_mtx); continue; } /* Copy w1 locally so we can release the spin lock. */ *tmp_w1 = *w1; mtx_unlock_spin(&w_mtx); if (tmp_w1->w_reversed == 0) continue; for (j = 1; j < w_max_used_index; j++) { if ((w_rmatrix[i][j] & WITNESS_REVERSAL) == 0 || i > j) continue; mtx_lock_spin(&w_mtx); if (generation != w_generation) { mtx_unlock_spin(&w_mtx); /* The graph has changed, try again. */ *oldidx = 0; sbuf_clear(sb); goto restart; } w2 = &w_data[j]; data1 = witness_lock_order_get(w1, w2); data2 = witness_lock_order_get(w2, w1); /* * Copy information locally so we can release the * spin lock. */ *tmp_w2 = *w2; if (data1) { stack_zero(&tmp_data1->wlod_stack); stack_copy(&data1->wlod_stack, &tmp_data1->wlod_stack); } if (data2 && data2 != data1) { stack_zero(&tmp_data2->wlod_stack); stack_copy(&data2->wlod_stack, &tmp_data2->wlod_stack); } mtx_unlock_spin(&w_mtx); sbuf_printf(sb, "\nLock order reversal between \"%s\"(%s) and \"%s\"(%s)!\n", tmp_w1->w_name, tmp_w1->w_class->lc_name, tmp_w2->w_name, tmp_w2->w_class->lc_name); if (data1) { sbuf_printf(sb, "Lock order \"%s\"(%s) -> \"%s\"(%s) first seen at:\n", tmp_w1->w_name, tmp_w1->w_class->lc_name, tmp_w2->w_name, tmp_w2->w_class->lc_name); stack_sbuf_print(sb, &tmp_data1->wlod_stack); sbuf_printf(sb, "\n"); } if (data2 && data2 != data1) { sbuf_printf(sb, "Lock order \"%s\"(%s) -> \"%s\"(%s) first seen at:\n", tmp_w2->w_name, tmp_w2->w_class->lc_name, tmp_w1->w_name, tmp_w1->w_class->lc_name); stack_sbuf_print(sb, &tmp_data2->wlod_stack); sbuf_printf(sb, "\n"); } } } mtx_lock_spin(&w_mtx); if (generation != w_generation) { mtx_unlock_spin(&w_mtx); /* * The graph changed while we were printing stack data, * try again. */ *oldidx = 0; sbuf_clear(sb); goto restart; } mtx_unlock_spin(&w_mtx); /* Free temporary storage space. */ free(tmp_data1, M_TEMP); free(tmp_data2, M_TEMP); free(tmp_w1, M_TEMP); free(tmp_w2, M_TEMP); } static int sysctl_debug_witness_badstacks(SYSCTL_HANDLER_ARGS) { struct sbuf *sb; int error; if (witness_watch < 1) { error = SYSCTL_OUT(req, w_notrunning, sizeof(w_notrunning)); return (error); } if (witness_cold) { error = SYSCTL_OUT(req, w_stillcold, sizeof(w_stillcold)); return (error); } error = 0; sb = sbuf_new(NULL, NULL, badstack_sbuf_size, SBUF_AUTOEXTEND); if (sb == NULL) return (ENOMEM); sbuf_print_witness_badstacks(sb, &req->oldidx); sbuf_finish(sb); error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1); sbuf_delete(sb); return (error); } #ifdef DDB static int sbuf_db_printf_drain(void *arg __unused, const char *data, int len) { return (db_printf("%.*s", len, data)); } DB_SHOW_COMMAND(badstacks, db_witness_badstacks) { struct sbuf sb; char buffer[128]; size_t dummy; sbuf_new(&sb, buffer, sizeof(buffer), SBUF_FIXEDLEN); sbuf_set_drain(&sb, sbuf_db_printf_drain, NULL); sbuf_print_witness_badstacks(&sb, &dummy); sbuf_finish(&sb); } #endif static int sysctl_debug_witness_channel(SYSCTL_HANDLER_ARGS) { static const struct { enum witness_channel channel; const char *name; } channels[] = { { WITNESS_CONSOLE, "console" }, { WITNESS_LOG, "log" }, { WITNESS_NONE, "none" }, }; char buf[16]; u_int i; int error; buf[0] = '\0'; for (i = 0; i < nitems(channels); i++) if (witness_channel == channels[i].channel) { snprintf(buf, sizeof(buf), "%s", channels[i].name); break; } error = sysctl_handle_string(oidp, buf, sizeof(buf), req); if (error != 0 || req->newptr == NULL) return (error); error = EINVAL; for (i = 0; i < nitems(channels); i++) if (strcmp(channels[i].name, buf) == 0) { witness_channel = channels[i].channel; error = 0; break; } return (error); } static int sysctl_debug_witness_fullgraph(SYSCTL_HANDLER_ARGS) { struct witness *w; struct sbuf *sb; int error; if (witness_watch < 1) { error = SYSCTL_OUT(req, w_notrunning, sizeof(w_notrunning)); return (error); } if (witness_cold) { error = SYSCTL_OUT(req, w_stillcold, sizeof(w_stillcold)); return (error); } error = 0; error = sysctl_wire_old_buffer(req, 0); if (error != 0) return (error); sb = sbuf_new_for_sysctl(NULL, NULL, FULLGRAPH_SBUF_SIZE, req); if (sb == NULL) return (ENOMEM); sbuf_printf(sb, "\n"); mtx_lock_spin(&w_mtx); STAILQ_FOREACH(w, &w_all, w_list) w->w_displayed = 0; STAILQ_FOREACH(w, &w_all, w_list) witness_add_fullgraph(sb, w); mtx_unlock_spin(&w_mtx); /* * Close the sbuf and return to userland. */ error = sbuf_finish(sb); sbuf_delete(sb); return (error); } static int sysctl_debug_witness_watch(SYSCTL_HANDLER_ARGS) { int error, value; value = witness_watch; error = sysctl_handle_int(oidp, &value, 0, req); if (error != 0 || req->newptr == NULL) return (error); if (value > 1 || value < -1 || (witness_watch == -1 && value != witness_watch)) return (EINVAL); witness_watch = value; return (0); } static void witness_add_fullgraph(struct sbuf *sb, struct witness *w) { int i; if (w->w_displayed != 0 || (w->w_file == NULL && w->w_line == 0)) return; w->w_displayed = 1; WITNESS_INDEX_ASSERT(w->w_index); for (i = 1; i <= w_max_used_index; i++) { if (w_rmatrix[w->w_index][i] & WITNESS_PARENT) { sbuf_printf(sb, "\"%s\",\"%s\"\n", w->w_name, w_data[i].w_name); witness_add_fullgraph(sb, &w_data[i]); } } } /* * A simple hash function. Takes a key pointer and a key size. If size == 0, * interprets the key as a string and reads until the null * terminator. Otherwise, reads the first size bytes. Returns an unsigned 32-bit * hash value computed from the key. */ static uint32_t witness_hash_djb2(const uint8_t *key, uint32_t size) { unsigned int hash = 5381; int i; /* hash = hash * 33 + key[i] */ if (size) for (i = 0; i < size; i++) hash = ((hash << 5) + hash) + (unsigned int)key[i]; else for (i = 0; key[i] != 0; i++) hash = ((hash << 5) + hash) + (unsigned int)key[i]; return (hash); } /* * Initializes the two witness hash tables. Called exactly once from * witness_initialize(). */ static void witness_init_hash_tables(void) { int i; MPASS(witness_cold); /* Initialize the hash tables. */ for (i = 0; i < WITNESS_HASH_SIZE; i++) w_hash.wh_array[i] = NULL; w_hash.wh_size = WITNESS_HASH_SIZE; w_hash.wh_count = 0; /* Initialize the lock order data hash. */ w_lofree = NULL; for (i = 0; i < WITNESS_LO_DATA_COUNT; i++) { memset(&w_lodata[i], 0, sizeof(w_lodata[i])); w_lodata[i].wlod_next = w_lofree; w_lofree = &w_lodata[i]; } w_lohash.wloh_size = WITNESS_LO_HASH_SIZE; w_lohash.wloh_count = 0; for (i = 0; i < WITNESS_LO_HASH_SIZE; i++) w_lohash.wloh_array[i] = NULL; } static struct witness * witness_hash_get(const char *key) { struct witness *w; uint32_t hash; MPASS(key != NULL); if (witness_cold == 0) mtx_assert(&w_mtx, MA_OWNED); hash = witness_hash_djb2(key, 0) % w_hash.wh_size; w = w_hash.wh_array[hash]; while (w != NULL) { if (strcmp(w->w_name, key) == 0) goto out; w = w->w_hash_next; } out: return (w); } static void witness_hash_put(struct witness *w) { uint32_t hash; MPASS(w != NULL); MPASS(w->w_name != NULL); if (witness_cold == 0) mtx_assert(&w_mtx, MA_OWNED); KASSERT(witness_hash_get(w->w_name) == NULL, ("%s: trying to add a hash entry that already exists!", __func__)); KASSERT(w->w_hash_next == NULL, ("%s: w->w_hash_next != NULL", __func__)); hash = witness_hash_djb2(w->w_name, 0) % w_hash.wh_size; w->w_hash_next = w_hash.wh_array[hash]; w_hash.wh_array[hash] = w; w_hash.wh_count++; } static struct witness_lock_order_data * witness_lock_order_get(struct witness *parent, struct witness *child) { struct witness_lock_order_data *data = NULL; struct witness_lock_order_key key; unsigned int hash; MPASS(parent != NULL && child != NULL); key.from = parent->w_index; key.to = child->w_index; WITNESS_INDEX_ASSERT(key.from); WITNESS_INDEX_ASSERT(key.to); if ((w_rmatrix[parent->w_index][child->w_index] & WITNESS_LOCK_ORDER_KNOWN) == 0) goto out; hash = witness_hash_djb2((const char*)&key, sizeof(key)) % w_lohash.wloh_size; data = w_lohash.wloh_array[hash]; while (data != NULL) { if (witness_lock_order_key_equal(&data->wlod_key, &key)) break; data = data->wlod_next; } out: return (data); } /* * Verify that parent and child have a known relationship, are not the same, * and child is actually a child of parent. This is done without w_mtx * to avoid contention in the common case. */ static int witness_lock_order_check(struct witness *parent, struct witness *child) { if (parent != child && w_rmatrix[parent->w_index][child->w_index] & WITNESS_LOCK_ORDER_KNOWN && isitmychild(parent, child)) return (1); return (0); } static int witness_lock_order_add(struct witness *parent, struct witness *child) { struct witness_lock_order_data *data = NULL; struct witness_lock_order_key key; unsigned int hash; MPASS(parent != NULL && child != NULL); key.from = parent->w_index; key.to = child->w_index; WITNESS_INDEX_ASSERT(key.from); WITNESS_INDEX_ASSERT(key.to); if (w_rmatrix[parent->w_index][child->w_index] & WITNESS_LOCK_ORDER_KNOWN) return (1); hash = witness_hash_djb2((const char*)&key, sizeof(key)) % w_lohash.wloh_size; w_rmatrix[parent->w_index][child->w_index] |= WITNESS_LOCK_ORDER_KNOWN; data = w_lofree; if (data == NULL) return (0); w_lofree = data->wlod_next; data->wlod_next = w_lohash.wloh_array[hash]; data->wlod_key = key; w_lohash.wloh_array[hash] = data; w_lohash.wloh_count++; stack_zero(&data->wlod_stack); stack_save(&data->wlod_stack); return (1); } /* Call this whenever the structure of the witness graph changes. */ static void witness_increment_graph_generation(void) { if (witness_cold == 0) mtx_assert(&w_mtx, MA_OWNED); w_generation++; } static int witness_output_drain(void *arg __unused, const char *data, int len) { witness_output("%.*s", len, data); return (len); } static void witness_debugger(int cond, const char *msg) { char buf[32]; struct sbuf sb; struct stack st; if (!cond) return; if (witness_trace) { sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN); sbuf_set_drain(&sb, witness_output_drain, NULL); stack_zero(&st); stack_save(&st); witness_output("stack backtrace:\n"); stack_sbuf_print_ddb(&sb, &st); sbuf_finish(&sb); } #ifdef KDB if (witness_kdb) kdb_enter(KDB_WHY_WITNESS, msg); #endif } Index: head/sys/sys/lock.h =================================================================== --- head/sys/sys/lock.h (revision 331367) +++ head/sys/sys/lock.h (revision 331368) @@ -1,360 +1,362 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Berkeley Software Design Inc's name may not be used to endorse or * promote products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``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 BERKELEY SOFTWARE DESIGN INC BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from BSDI Id: mutex.h,v 2.7.2.35 2000/04/27 03:10:26 cp * $FreeBSD$ */ #ifndef _SYS_LOCK_H_ #define _SYS_LOCK_H_ #include #include #include struct lock_list_entry; struct thread; /* * Lock classes. Each lock has a class which describes characteristics * common to all types of locks of a given class. * * Spin locks in general must always protect against preemption, as it is * an error to perform any type of context switch while holding a spin lock. * Also, for an individual lock to be recursable, its class must allow * recursion and the lock itself must explicitly allow recursion. * * The 'lc_ddb_show' function pointer is used to dump class-specific * data for the 'show lock' DDB command. The 'lc_lock' and * 'lc_unlock' function pointers are used in sleep(9) and cv_wait(9) * to lock and unlock locks while blocking on a sleep queue. The * return value of 'lc_unlock' will be passed to 'lc_lock' on resume * to allow communication of state between the two routines. */ struct lock_class { const char *lc_name; u_int lc_flags; void (*lc_assert)(const struct lock_object *lock, int what); void (*lc_ddb_show)(const struct lock_object *lock); void (*lc_lock)(struct lock_object *lock, uintptr_t how); int (*lc_owner)(const struct lock_object *lock, struct thread **owner); uintptr_t (*lc_unlock)(struct lock_object *lock); }; #define LC_SLEEPLOCK 0x00000001 /* Sleep lock. */ #define LC_SPINLOCK 0x00000002 /* Spin lock. */ #define LC_SLEEPABLE 0x00000004 /* Sleeping allowed with this lock. */ #define LC_RECURSABLE 0x00000008 /* Locks of this type may recurse. */ #define LC_UPGRADABLE 0x00000010 /* Upgrades and downgrades permitted. */ #define LO_CLASSFLAGS 0x0000ffff /* Class specific flags. */ #define LO_INITIALIZED 0x00010000 /* Lock has been initialized. */ #define LO_WITNESS 0x00020000 /* Should witness monitor this lock. */ #define LO_QUIET 0x00040000 /* Don't log locking operations. */ #define LO_RECURSABLE 0x00080000 /* Lock may recurse. */ #define LO_SLEEPABLE 0x00100000 /* Lock may be held while sleeping. */ #define LO_UPGRADABLE 0x00200000 /* Lock may be upgraded/downgraded. */ #define LO_DUPOK 0x00400000 /* Don't check for duplicate acquires */ #define LO_IS_VNODE 0x00800000 /* Tell WITNESS about a VNODE lock */ #define LO_CLASSMASK 0x0f000000 /* Class index bitmask. */ #define LO_NOPROFILE 0x10000000 /* Don't profile this lock */ #define LO_NEW 0x20000000 /* Don't check for double-init */ /* * Lock classes are statically assigned an index into the gobal lock_classes * array. Debugging code looks up the lock class for a given lock object * by indexing the array. */ #define LO_CLASSSHIFT 24 #define LO_CLASSINDEX(lock) ((((lock)->lo_flags) & LO_CLASSMASK) >> LO_CLASSSHIFT) #define LOCK_CLASS(lock) (lock_classes[LO_CLASSINDEX((lock))]) #define LOCK_CLASS_MAX (LO_CLASSMASK >> LO_CLASSSHIFT) /* * Option flags passed to lock operations that witness also needs to know * about or that are generic across all locks. */ #define LOP_NEWORDER 0x00000001 /* Define a new lock order. */ #define LOP_QUIET 0x00000002 /* Don't log locking operations. */ #define LOP_TRYLOCK 0x00000004 /* Don't check lock order. */ #define LOP_EXCLUSIVE 0x00000008 /* Exclusive lock. */ #define LOP_DUPOK 0x00000010 /* Don't check for duplicate acquires */ /* Flags passed to witness_assert. */ #define LA_MASKASSERT 0x000000ff /* Mask for witness defined asserts. */ #define LA_UNLOCKED 0x00000000 /* Lock is unlocked. */ #define LA_LOCKED 0x00000001 /* Lock is at least share locked. */ #define LA_SLOCKED 0x00000002 /* Lock is exactly share locked. */ #define LA_XLOCKED 0x00000004 /* Lock is exclusively locked. */ #define LA_RECURSED 0x00000008 /* Lock is recursed. */ #define LA_NOTRECURSED 0x00000010 /* Lock is not recursed. */ #ifdef _KERNEL /* * If any of WITNESS, INVARIANTS, or KTR_LOCK KTR tracing has been enabled, * then turn on LOCK_DEBUG. When this option is on, extra debugging * facilities such as tracking the file and line number of lock operations * are enabled. Also, mutex locking operations are not inlined to avoid * bloat from all the extra debugging code. We also have to turn on all the * calling conventions for this debugging code in modules so that modules can * work with both debug and non-debug kernels. */ #if defined(KLD_MODULE) || defined(WITNESS) || defined(INVARIANTS) || \ defined(LOCK_PROFILING) || defined(KTR) #define LOCK_DEBUG 1 #else #define LOCK_DEBUG 0 #endif /* * In the LOCK_DEBUG case, use the filename and line numbers for debugging * operations. Otherwise, use default values to avoid the unneeded bloat. */ #if LOCK_DEBUG > 0 #define LOCK_FILE_LINE_ARG_DEF , const char *file, int line #define LOCK_FILE_LINE_ARG , file, line #define LOCK_FILE __FILE__ #define LOCK_LINE __LINE__ #else #define LOCK_FILE_LINE_ARG_DEF #define LOCK_FILE_LINE_ARG #define LOCK_FILE NULL #define LOCK_LINE 0 #endif /* * Macros for KTR_LOCK tracing. * * opname - name of this operation (LOCK/UNLOCK/SLOCK, etc.) * lo - struct lock_object * for this lock * flags - flags passed to the lock operation * recurse - this locks recursion level (or 0 if class is not recursable) * result - result of a try lock operation * file - file name * line - line number */ #if LOCK_DEBUG > 0 #define LOCK_LOG_TEST(lo, flags) \ (((flags) & LOP_QUIET) == 0 && ((lo)->lo_flags & LO_QUIET) == 0) #else #define LOCK_LOG_TEST(lo, flags) 0 #endif #define LOCK_LOG_LOCK(opname, lo, flags, recurse, file, line) do { \ if (LOCK_LOG_TEST((lo), (flags))) \ CTR6(KTR_LOCK, opname " (%s) %s %p r = %d at %s:%d", \ LOCK_CLASS(lo)->lc_name, (lo)->lo_name, \ (lo), (u_int)(recurse), (file), (line)); \ } while (0) #define LOCK_LOG_TRY(opname, lo, flags, result, file, line) do { \ if (LOCK_LOG_TEST((lo), (flags))) \ CTR6(KTR_LOCK, "TRY_" opname " (%s) %s %p result=%d at %s:%d",\ LOCK_CLASS(lo)->lc_name, (lo)->lo_name, \ (lo), (u_int)(result), (file), (line)); \ } while (0) #define LOCK_LOG_INIT(lo, flags) do { \ if (LOCK_LOG_TEST((lo), (flags))) \ CTR4(KTR_LOCK, "%s: %p (%s) %s", __func__, (lo), \ LOCK_CLASS(lo)->lc_name, (lo)->lo_name); \ } while (0) #define LOCK_LOG_DESTROY(lo, flags) LOCK_LOG_INIT(lo, flags) #define lock_initialized(lo) ((lo)->lo_flags & LO_INITIALIZED) /* * Helpful macros for quickly coming up with assertions with informative * panic messages. */ #define MPASS(ex) MPASS4(ex, #ex, __FILE__, __LINE__) #define MPASS2(ex, what) MPASS4(ex, what, __FILE__, __LINE__) #define MPASS3(ex, file, line) MPASS4(ex, #ex, file, line) #define MPASS4(ex, what, file, line) \ KASSERT((ex), ("Assertion %s failed at %s:%d", what, file, line)) extern struct lock_class lock_class_mtx_sleep; extern struct lock_class lock_class_mtx_spin; extern struct lock_class lock_class_sx; extern struct lock_class lock_class_rw; extern struct lock_class lock_class_rm; extern struct lock_class lock_class_rm_sleepable; extern struct lock_class lock_class_lockmgr; extern struct lock_class *lock_classes[]; struct lock_delay_config { u_int base; u_int max; }; struct lock_delay_arg { struct lock_delay_config *config; u_int delay; u_int spin_cnt; }; static inline void lock_delay_arg_init(struct lock_delay_arg *la, struct lock_delay_config *lc) { la->config = lc; la->delay = lc->base; la->spin_cnt = 0; } #define lock_delay_spin(n) do { \ u_int _i; \ \ for (_i = (n); _i > 0; _i--) \ cpu_spinwait(); \ } while (0) #define LOCK_DELAY_SYSINIT(func) \ SYSINIT(func##_ld, SI_SUB_LOCK, SI_ORDER_ANY, func, NULL) #define LOCK_DELAY_SYSINIT_DEFAULT(lc) \ SYSINIT(lock_delay_##lc##_ld, SI_SUB_LOCK, SI_ORDER_ANY, \ lock_delay_default_init, &lc) void lock_init(struct lock_object *, struct lock_class *, const char *, const char *, int); void lock_destroy(struct lock_object *); void lock_delay(struct lock_delay_arg *); void lock_delay_default_init(struct lock_delay_config *); void spinlock_enter(void); void spinlock_exit(void); void witness_init(struct lock_object *, const char *); void witness_destroy(struct lock_object *); int witness_defineorder(struct lock_object *, struct lock_object *); void witness_checkorder(struct lock_object *, int, const char *, int, struct lock_object *); void witness_lock(struct lock_object *, int, const char *, int); void witness_upgrade(struct lock_object *, int, const char *, int); void witness_downgrade(struct lock_object *, int, const char *, int); void witness_unlock(struct lock_object *, int, const char *, int); void witness_save(struct lock_object *, const char **, int *); void witness_restore(struct lock_object *, const char *, int); int witness_list_locks(struct lock_list_entry **, int (*)(const char *, ...)); int witness_warn(int, struct lock_object *, const char *, ...); void witness_assert(const struct lock_object *, int, const char *, int); void witness_display_spinlock(struct lock_object *, struct thread *, int (*)(const char *, ...)); int witness_line(struct lock_object *); void witness_norelease(struct lock_object *); void witness_releaseok(struct lock_object *); const char *witness_file(struct lock_object *); void witness_thread_exit(struct thread *); #ifdef WITNESS +int witness_startup_count(void); +void witness_startup(void *); /* Flags for witness_warn(). */ #define WARN_GIANTOK 0x01 /* Giant is exempt from this check. */ #define WARN_PANIC 0x02 /* Panic if check fails. */ #define WARN_SLEEPOK 0x04 /* Sleepable locks are exempt from check. */ #define WITNESS_INIT(lock, type) \ witness_init((lock), (type)) #define WITNESS_DESTROY(lock) \ witness_destroy(lock) #define WITNESS_CHECKORDER(lock, flags, file, line, interlock) \ witness_checkorder((lock), (flags), (file), (line), (interlock)) #define WITNESS_DEFINEORDER(lock1, lock2) \ witness_defineorder((struct lock_object *)(lock1), \ (struct lock_object *)(lock2)) #define WITNESS_LOCK(lock, flags, file, line) \ witness_lock((lock), (flags), (file), (line)) #define WITNESS_UPGRADE(lock, flags, file, line) \ witness_upgrade((lock), (flags), (file), (line)) #define WITNESS_DOWNGRADE(lock, flags, file, line) \ witness_downgrade((lock), (flags), (file), (line)) #define WITNESS_UNLOCK(lock, flags, file, line) \ witness_unlock((lock), (flags), (file), (line)) #define WITNESS_CHECK(flags, lock, fmt, ...) \ witness_warn((flags), (lock), (fmt), ## __VA_ARGS__) #define WITNESS_WARN(flags, lock, fmt, ...) \ witness_warn((flags), (lock), (fmt), ## __VA_ARGS__) #define WITNESS_SAVE_DECL(n) \ const char * __CONCAT(n, __wf); \ int __CONCAT(n, __wl) #define WITNESS_SAVE(lock, n) \ witness_save((lock), &__CONCAT(n, __wf), &__CONCAT(n, __wl)) #define WITNESS_RESTORE(lock, n) \ witness_restore((lock), __CONCAT(n, __wf), __CONCAT(n, __wl)) #define WITNESS_NORELEASE(lock) \ witness_norelease(&(lock)->lock_object) #define WITNESS_RELEASEOK(lock) \ witness_releaseok(&(lock)->lock_object) #define WITNESS_FILE(lock) \ witness_file(lock) #define WITNESS_LINE(lock) \ witness_line(lock) #else /* WITNESS */ #define WITNESS_INIT(lock, type) (void)0 #define WITNESS_DESTROY(lock) (void)0 #define WITNESS_DEFINEORDER(lock1, lock2) 0 #define WITNESS_CHECKORDER(lock, flags, file, line, interlock) (void)0 #define WITNESS_LOCK(lock, flags, file, line) (void)0 #define WITNESS_UPGRADE(lock, flags, file, line) (void)0 #define WITNESS_DOWNGRADE(lock, flags, file, line) (void)0 #define WITNESS_UNLOCK(lock, flags, file, line) (void)0 #define WITNESS_CHECK(flags, lock, fmt, ...) 0 #define WITNESS_WARN(flags, lock, fmt, ...) (void)0 #define WITNESS_SAVE_DECL(n) (void)0 #define WITNESS_SAVE(lock, n) (void)0 #define WITNESS_RESTORE(lock, n) (void)0 #define WITNESS_NORELEASE(lock) (void)0 #define WITNESS_RELEASEOK(lock) (void)0 #define WITNESS_FILE(lock) ("?") #define WITNESS_LINE(lock) (0) #endif /* WITNESS */ #endif /* _KERNEL */ #endif /* _SYS_LOCK_H_ */ Index: head/sys/vm/vm_page.c =================================================================== --- head/sys/vm/vm_page.c (revision 331367) +++ head/sys/vm/vm_page.c (revision 331368) @@ -1,4227 +1,4236 @@ /*- * SPDX-License-Identifier: (BSD-3-Clause AND MIT-CMU) * * Copyright (c) 1991 Regents of the University of California. * All rights reserved. * Copyright (c) 1998 Matthew Dillon. All Rights Reserved. * * This code is derived from software contributed to Berkeley by * The Mach Operating System project at Carnegie-Mellon University. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91 */ /*- * Copyright (c) 1987, 1990 Carnegie-Mellon University. * All rights reserved. * * Authors: Avadis Tevanian, Jr., Michael Wayne Young * * Permission to use, copy, modify and distribute this software and * its documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. */ /* * GENERAL RULES ON VM_PAGE MANIPULATION * * - A page queue lock is required when adding or removing a page from a * page queue regardless of other locks or the busy state of a page. * * * In general, no thread besides the page daemon can acquire or * hold more than one page queue lock at a time. * * * The page daemon can acquire and hold any pair of page queue * locks in any order. * * - The object lock is required when inserting or removing * pages from an object (vm_page_insert() or vm_page_remove()). * */ /* * Resident memory management module. */ #include __FBSDID("$FreeBSD$"); #include "opt_vm.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern int uma_startup_count(int); extern void uma_startup(void *, int); extern int vmem_startup_count(void); /* * Associated with page of user-allocatable memory is a * page structure. */ struct vm_domain vm_dom[MAXMEMDOM]; struct mtx_padalign __exclusive_cache_line pa_lock[PA_LOCK_COUNT]; struct mtx_padalign __exclusive_cache_line vm_domainset_lock; /* The following fields are protected by the domainset lock. */ domainset_t __exclusive_cache_line vm_min_domains; domainset_t __exclusive_cache_line vm_severe_domains; static int vm_min_waiters; static int vm_severe_waiters; static int vm_pageproc_waiters; /* * bogus page -- for I/O to/from partially complete buffers, * or for paging into sparsely invalid regions. */ vm_page_t bogus_page; vm_page_t vm_page_array; long vm_page_array_size; long first_page; static int boot_pages; SYSCTL_INT(_vm, OID_AUTO, boot_pages, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &boot_pages, 0, "number of pages allocated for bootstrapping the VM system"); static int pa_tryrelock_restart; SYSCTL_INT(_vm, OID_AUTO, tryrelock_restart, CTLFLAG_RD, &pa_tryrelock_restart, 0, "Number of tryrelock restarts"); static TAILQ_HEAD(, vm_page) blacklist_head; static int sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS); SYSCTL_PROC(_vm, OID_AUTO, page_blacklist, CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_page_blacklist, "A", "Blacklist pages"); static uma_zone_t fakepg_zone; static void vm_page_alloc_check(vm_page_t m); static void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits); static void vm_page_enqueue(uint8_t queue, vm_page_t m); static void vm_page_free_phys(struct vm_domain *vmd, vm_page_t m); static void vm_page_init(void *dummy); static int vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex, vm_page_t mpred); static void vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred); static int vm_page_reclaim_run(int req_class, int domain, u_long npages, vm_page_t m_run, vm_paddr_t high); static int vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object, int req); SYSINIT(vm_page, SI_SUB_VM, SI_ORDER_SECOND, vm_page_init, NULL); static void vm_page_init(void *dummy) { fakepg_zone = uma_zcreate("fakepg", sizeof(struct vm_page), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE | UMA_ZONE_VM); bogus_page = vm_page_alloc(NULL, 0, VM_ALLOC_NOOBJ | VM_ALLOC_NORMAL | VM_ALLOC_WIRED); } /* Make sure that u_long is at least 64 bits when PAGE_SIZE is 32K. */ #if PAGE_SIZE == 32768 #ifdef CTASSERT CTASSERT(sizeof(u_long) >= 8); #endif #endif /* * Try to acquire a physical address lock while a pmap is locked. If we * fail to trylock we unlock and lock the pmap directly and cache the * locked pa in *locked. The caller should then restart their loop in case * the virtual to physical mapping has changed. */ int vm_page_pa_tryrelock(pmap_t pmap, vm_paddr_t pa, vm_paddr_t *locked) { vm_paddr_t lockpa; lockpa = *locked; *locked = pa; if (lockpa) { PA_LOCK_ASSERT(lockpa, MA_OWNED); if (PA_LOCKPTR(pa) == PA_LOCKPTR(lockpa)) return (0); PA_UNLOCK(lockpa); } if (PA_TRYLOCK(pa)) return (0); PMAP_UNLOCK(pmap); atomic_add_int(&pa_tryrelock_restart, 1); PA_LOCK(pa); PMAP_LOCK(pmap); return (EAGAIN); } /* * vm_set_page_size: * * Sets the page size, perhaps based upon the memory * size. Must be called before any use of page-size * dependent functions. */ void vm_set_page_size(void) { if (vm_cnt.v_page_size == 0) vm_cnt.v_page_size = PAGE_SIZE; if (((vm_cnt.v_page_size - 1) & vm_cnt.v_page_size) != 0) panic("vm_set_page_size: page size not a power of two"); } /* * vm_page_blacklist_next: * * Find the next entry in the provided string of blacklist * addresses. Entries are separated by space, comma, or newline. * If an invalid integer is encountered then the rest of the * string is skipped. Updates the list pointer to the next * character, or NULL if the string is exhausted or invalid. */ static vm_paddr_t vm_page_blacklist_next(char **list, char *end) { vm_paddr_t bad; char *cp, *pos; if (list == NULL || *list == NULL) return (0); if (**list =='\0') { *list = NULL; return (0); } /* * If there's no end pointer then the buffer is coming from * the kenv and we know it's null-terminated. */ if (end == NULL) end = *list + strlen(*list); /* Ensure that strtoq() won't walk off the end */ if (*end != '\0') { if (*end == '\n' || *end == ' ' || *end == ',') *end = '\0'; else { printf("Blacklist not terminated, skipping\n"); *list = NULL; return (0); } } for (pos = *list; *pos != '\0'; pos = cp) { bad = strtoq(pos, &cp, 0); if (*cp == '\0' || *cp == ' ' || *cp == ',' || *cp == '\n') { if (bad == 0) { if (++cp < end) continue; else break; } } else break; if (*cp == '\0' || ++cp >= end) *list = NULL; else *list = cp; return (trunc_page(bad)); } printf("Garbage in RAM blacklist, skipping\n"); *list = NULL; return (0); } /* * vm_page_blacklist_check: * * Iterate through the provided string of blacklist addresses, pulling * each entry out of the physical allocator free list and putting it * onto a list for reporting via the vm.page_blacklist sysctl. */ static void vm_page_blacklist_check(char *list, char *end) { struct vm_domain *vmd; vm_paddr_t pa; vm_page_t m; char *next; int ret; next = list; while (next != NULL) { if ((pa = vm_page_blacklist_next(&next, end)) == 0) continue; m = vm_phys_paddr_to_vm_page(pa); if (m == NULL) continue; vmd = vm_pagequeue_domain(m); vm_domain_free_lock(vmd); ret = vm_phys_unfree_page(m); vm_domain_free_unlock(vmd); if (ret == TRUE) { TAILQ_INSERT_TAIL(&blacklist_head, m, listq); if (bootverbose) printf("Skipping page with pa 0x%jx\n", (uintmax_t)pa); } } } /* * vm_page_blacklist_load: * * Search for a special module named "ram_blacklist". It'll be a * plain text file provided by the user via the loader directive * of the same name. */ static void vm_page_blacklist_load(char **list, char **end) { void *mod; u_char *ptr; u_int len; mod = NULL; ptr = NULL; mod = preload_search_by_type("ram_blacklist"); if (mod != NULL) { ptr = preload_fetch_addr(mod); len = preload_fetch_size(mod); } *list = ptr; if (ptr != NULL) *end = ptr + len; else *end = NULL; return; } static int sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS) { vm_page_t m; struct sbuf sbuf; int error, first; first = 1; error = sysctl_wire_old_buffer(req, 0); if (error != 0) return (error); sbuf_new_for_sysctl(&sbuf, NULL, 128, req); TAILQ_FOREACH(m, &blacklist_head, listq) { sbuf_printf(&sbuf, "%s%#jx", first ? "" : ",", (uintmax_t)m->phys_addr); first = 0; } error = sbuf_finish(&sbuf); sbuf_delete(&sbuf); return (error); } static void vm_page_domain_init(int domain) { struct vm_domain *vmd; struct vm_pagequeue *pq; int i; vmd = VM_DOMAIN(domain); bzero(vmd, sizeof(*vmd)); *__DECONST(char **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_name) = "vm inactive pagequeue"; *__DECONST(char **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_name) = "vm active pagequeue"; *__DECONST(char **, &vmd->vmd_pagequeues[PQ_LAUNDRY].pq_name) = "vm laundry pagequeue"; *__DECONST(char **, &vmd->vmd_pagequeues[PQ_UNSWAPPABLE].pq_name) = "vm unswappable pagequeue"; vmd->vmd_domain = domain; vmd->vmd_page_count = 0; vmd->vmd_free_count = 0; vmd->vmd_segs = 0; vmd->vmd_oom = FALSE; for (i = 0; i < PQ_COUNT; i++) { pq = &vmd->vmd_pagequeues[i]; TAILQ_INIT(&pq->pq_pl); mtx_init(&pq->pq_mutex, pq->pq_name, "vm pagequeue", MTX_DEF | MTX_DUPOK); } mtx_init(&vmd->vmd_free_mtx, "vm page free queue", NULL, MTX_DEF); mtx_init(&vmd->vmd_pageout_mtx, "vm pageout lock", NULL, MTX_DEF); snprintf(vmd->vmd_name, sizeof(vmd->vmd_name), "%d", domain); } /* * Initialize a physical page in preparation for adding it to the free * lists. */ static void vm_page_init_page(vm_page_t m, vm_paddr_t pa, int segind) { m->object = NULL; m->wire_count = 0; m->busy_lock = VPB_UNBUSIED; m->hold_count = 0; m->flags = 0; m->phys_addr = pa; m->queue = PQ_NONE; m->psind = 0; m->segind = segind; m->order = VM_NFREEORDER; m->pool = VM_FREEPOOL_DEFAULT; m->valid = m->dirty = 0; pmap_page_init(m); } /* * vm_page_startup: * * Initializes the resident memory module. Allocates physical memory for * bootstrapping UMA and some data structures that are used to manage * physical pages. Initializes these structures, and populates the free * page queues. */ vm_offset_t vm_page_startup(vm_offset_t vaddr) { struct vm_phys_seg *seg; vm_page_t m; char *list, *listend; vm_offset_t mapped; vm_paddr_t end, high_avail, low_avail, new_end, page_range, size; vm_paddr_t biggestsize, last_pa, pa; u_long pagecount; int biggestone, i, segind; biggestsize = 0; biggestone = 0; vaddr = round_page(vaddr); for (i = 0; phys_avail[i + 1]; i += 2) { phys_avail[i] = round_page(phys_avail[i]); phys_avail[i + 1] = trunc_page(phys_avail[i + 1]); } for (i = 0; phys_avail[i + 1]; i += 2) { size = phys_avail[i + 1] - phys_avail[i]; if (size > biggestsize) { biggestone = i; biggestsize = size; } } end = phys_avail[biggestone+1]; /* * Initialize the page and queue locks. */ mtx_init(&vm_domainset_lock, "vm domainset lock", NULL, MTX_DEF); for (i = 0; i < PA_LOCK_COUNT; i++) mtx_init(&pa_lock[i], "vm page", NULL, MTX_DEF); for (i = 0; i < vm_ndomains; i++) vm_page_domain_init(i); /* * Allocate memory for use when boot strapping the kernel memory * allocator. Tell UMA how many zones we are going to create * before going fully functional. UMA will add its zones. * * VM startup zones: vmem, vmem_btag, VM OBJECT, RADIX NODE, MAP, * KMAP ENTRY, MAP ENTRY, VMSPACE. */ boot_pages = uma_startup_count(8); #ifndef UMA_MD_SMALL_ALLOC /* vmem_startup() calls uma_prealloc(). */ boot_pages += vmem_startup_count(); /* vm_map_startup() calls uma_prealloc(). */ boot_pages += howmany(MAX_KMAP, UMA_SLAB_SPACE / sizeof(struct vm_map)); /* * Before going fully functional kmem_init() does allocation * from "KMAP ENTRY" and vmem_create() does allocation from "vmem". */ boot_pages += 2; #endif /* * CTFLAG_RDTUN doesn't work during the early boot process, so we must * manually fetch the value. */ TUNABLE_INT_FETCH("vm.boot_pages", &boot_pages); new_end = end - (boot_pages * UMA_SLAB_SIZE); new_end = trunc_page(new_end); mapped = pmap_map(&vaddr, new_end, end, VM_PROT_READ | VM_PROT_WRITE); bzero((void *)mapped, end - new_end); uma_startup((void *)mapped, boot_pages); +#ifdef WITNESS + end = new_end; + new_end = end - round_page(witness_startup_count()); + mapped = pmap_map(&vaddr, new_end, end, + VM_PROT_READ | VM_PROT_WRITE); + bzero((void *)mapped, end - new_end); + witness_startup((void *)mapped); +#endif + #if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \ defined(__i386__) || defined(__mips__) /* * Allocate a bitmap to indicate that a random physical page * needs to be included in a minidump. * * The amd64 port needs this to indicate which direct map pages * need to be dumped, via calls to dump_add_page()/dump_drop_page(). * * However, i386 still needs this workspace internally within the * minidump code. In theory, they are not needed on i386, but are * included should the sf_buf code decide to use them. */ last_pa = 0; for (i = 0; dump_avail[i + 1] != 0; i += 2) if (dump_avail[i + 1] > last_pa) last_pa = dump_avail[i + 1]; page_range = last_pa / PAGE_SIZE; vm_page_dump_size = round_page(roundup2(page_range, NBBY) / NBBY); new_end -= vm_page_dump_size; vm_page_dump = (void *)(uintptr_t)pmap_map(&vaddr, new_end, new_end + vm_page_dump_size, VM_PROT_READ | VM_PROT_WRITE); bzero((void *)vm_page_dump, vm_page_dump_size); #else (void)last_pa; #endif #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) /* * Include the UMA bootstrap pages and vm_page_dump in a crash dump. * When pmap_map() uses the direct map, they are not automatically * included. */ for (pa = new_end; pa < end; pa += PAGE_SIZE) dump_add_page(pa); #endif phys_avail[biggestone + 1] = new_end; #ifdef __amd64__ /* * Request that the physical pages underlying the message buffer be * included in a crash dump. Since the message buffer is accessed * through the direct map, they are not automatically included. */ pa = DMAP_TO_PHYS((vm_offset_t)msgbufp->msg_ptr); last_pa = pa + round_page(msgbufsize); while (pa < last_pa) { dump_add_page(pa); pa += PAGE_SIZE; } #endif /* * Compute the number of pages of memory that will be available for * use, taking into account the overhead of a page structure per page. * In other words, solve * "available physical memory" - round_page(page_range * * sizeof(struct vm_page)) = page_range * PAGE_SIZE * for page_range. */ low_avail = phys_avail[0]; high_avail = phys_avail[1]; for (i = 0; i < vm_phys_nsegs; i++) { if (vm_phys_segs[i].start < low_avail) low_avail = vm_phys_segs[i].start; if (vm_phys_segs[i].end > high_avail) high_avail = vm_phys_segs[i].end; } /* Skip the first chunk. It is already accounted for. */ for (i = 2; phys_avail[i + 1] != 0; i += 2) { if (phys_avail[i] < low_avail) low_avail = phys_avail[i]; if (phys_avail[i + 1] > high_avail) high_avail = phys_avail[i + 1]; } first_page = low_avail / PAGE_SIZE; #ifdef VM_PHYSSEG_SPARSE size = 0; for (i = 0; i < vm_phys_nsegs; i++) size += vm_phys_segs[i].end - vm_phys_segs[i].start; for (i = 0; phys_avail[i + 1] != 0; i += 2) size += phys_avail[i + 1] - phys_avail[i]; #elif defined(VM_PHYSSEG_DENSE) size = high_avail - low_avail; #else #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." #endif #ifdef VM_PHYSSEG_DENSE /* * In the VM_PHYSSEG_DENSE case, the number of pages can account for * the overhead of a page structure per page only if vm_page_array is * allocated from the last physical memory chunk. Otherwise, we must * allocate page structures representing the physical memory * underlying vm_page_array, even though they will not be used. */ if (new_end != high_avail) page_range = size / PAGE_SIZE; else #endif { page_range = size / (PAGE_SIZE + sizeof(struct vm_page)); /* * If the partial bytes remaining are large enough for * a page (PAGE_SIZE) without a corresponding * 'struct vm_page', then new_end will contain an * extra page after subtracting the length of the VM * page array. Compensate by subtracting an extra * page from new_end. */ if (size % (PAGE_SIZE + sizeof(struct vm_page)) >= PAGE_SIZE) { if (new_end == high_avail) high_avail -= PAGE_SIZE; new_end -= PAGE_SIZE; } } end = new_end; /* * Reserve an unmapped guard page to trap access to vm_page_array[-1]. * However, because this page is allocated from KVM, out-of-bounds * accesses using the direct map will not be trapped. */ vaddr += PAGE_SIZE; /* * Allocate physical memory for the page structures, and map it. */ new_end = trunc_page(end - page_range * sizeof(struct vm_page)); mapped = pmap_map(&vaddr, new_end, end, VM_PROT_READ | VM_PROT_WRITE); vm_page_array = (vm_page_t)mapped; vm_page_array_size = page_range; #if VM_NRESERVLEVEL > 0 /* * Allocate physical memory for the reservation management system's * data structures, and map it. */ if (high_avail == end) high_avail = new_end; new_end = vm_reserv_startup(&vaddr, new_end, high_avail); #endif #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) /* * Include vm_page_array and vm_reserv_array in a crash dump. */ for (pa = new_end; pa < end; pa += PAGE_SIZE) dump_add_page(pa); #endif phys_avail[biggestone + 1] = new_end; /* * Add physical memory segments corresponding to the available * physical pages. */ for (i = 0; phys_avail[i + 1] != 0; i += 2) vm_phys_add_seg(phys_avail[i], phys_avail[i + 1]); /* * Initialize the physical memory allocator. */ vm_phys_init(); /* * Initialize the page structures and add every available page to the * physical memory allocator's free lists. */ vm_cnt.v_page_count = 0; for (segind = 0; segind < vm_phys_nsegs; segind++) { seg = &vm_phys_segs[segind]; for (m = seg->first_page, pa = seg->start; pa < seg->end; m++, pa += PAGE_SIZE) vm_page_init_page(m, pa, segind); /* * Add the segment to the free lists only if it is covered by * one of the ranges in phys_avail. Because we've added the * ranges to the vm_phys_segs array, we can assume that each * segment is either entirely contained in one of the ranges, * or doesn't overlap any of them. */ for (i = 0; phys_avail[i + 1] != 0; i += 2) { struct vm_domain *vmd; if (seg->start < phys_avail[i] || seg->end > phys_avail[i + 1]) continue; m = seg->first_page; pagecount = (u_long)atop(seg->end - seg->start); vmd = VM_DOMAIN(seg->domain); vm_domain_free_lock(vmd); vm_phys_free_contig(m, pagecount); vm_domain_free_unlock(vmd); vm_domain_freecnt_inc(vmd, pagecount); vm_cnt.v_page_count += (u_int)pagecount; vmd = VM_DOMAIN(seg->domain); vmd->vmd_page_count += (u_int)pagecount; vmd->vmd_segs |= 1UL << m->segind; break; } } /* * Remove blacklisted pages from the physical memory allocator. */ TAILQ_INIT(&blacklist_head); vm_page_blacklist_load(&list, &listend); vm_page_blacklist_check(list, listend); list = kern_getenv("vm.blacklist"); vm_page_blacklist_check(list, NULL); freeenv(list); #if VM_NRESERVLEVEL > 0 /* * Initialize the reservation management system. */ vm_reserv_init(); #endif /* * Set an initial domain policy for thread0 so that allocations * can work. */ domainset_zero(); return (vaddr); } void vm_page_reference(vm_page_t m) { vm_page_aflag_set(m, PGA_REFERENCED); } /* * vm_page_busy_downgrade: * * Downgrade an exclusive busy page into a single shared busy page. */ void vm_page_busy_downgrade(vm_page_t m) { u_int x; bool locked; vm_page_assert_xbusied(m); locked = mtx_owned(vm_page_lockptr(m)); for (;;) { x = m->busy_lock; x &= VPB_BIT_WAITERS; if (x != 0 && !locked) vm_page_lock(m); if (atomic_cmpset_rel_int(&m->busy_lock, VPB_SINGLE_EXCLUSIVER | x, VPB_SHARERS_WORD(1))) break; if (x != 0 && !locked) vm_page_unlock(m); } if (x != 0) { wakeup(m); if (!locked) vm_page_unlock(m); } } /* * vm_page_sbusied: * * Return a positive value if the page is shared busied, 0 otherwise. */ int vm_page_sbusied(vm_page_t m) { u_int x; x = m->busy_lock; return ((x & VPB_BIT_SHARED) != 0 && x != VPB_UNBUSIED); } /* * vm_page_sunbusy: * * Shared unbusy a page. */ void vm_page_sunbusy(vm_page_t m) { u_int x; vm_page_lock_assert(m, MA_NOTOWNED); vm_page_assert_sbusied(m); for (;;) { x = m->busy_lock; if (VPB_SHARERS(x) > 1) { if (atomic_cmpset_int(&m->busy_lock, x, x - VPB_ONE_SHARER)) break; continue; } if ((x & VPB_BIT_WAITERS) == 0) { KASSERT(x == VPB_SHARERS_WORD(1), ("vm_page_sunbusy: invalid lock state")); if (atomic_cmpset_int(&m->busy_lock, VPB_SHARERS_WORD(1), VPB_UNBUSIED)) break; continue; } KASSERT(x == (VPB_SHARERS_WORD(1) | VPB_BIT_WAITERS), ("vm_page_sunbusy: invalid lock state for waiters")); vm_page_lock(m); if (!atomic_cmpset_int(&m->busy_lock, x, VPB_UNBUSIED)) { vm_page_unlock(m); continue; } wakeup(m); vm_page_unlock(m); break; } } /* * vm_page_busy_sleep: * * Sleep and release the page lock, using the page pointer as wchan. * This is used to implement the hard-path of busying mechanism. * * The given page must be locked. * * If nonshared is true, sleep only if the page is xbusy. */ void vm_page_busy_sleep(vm_page_t m, const char *wmesg, bool nonshared) { u_int x; vm_page_assert_locked(m); x = m->busy_lock; if (x == VPB_UNBUSIED || (nonshared && (x & VPB_BIT_SHARED) != 0) || ((x & VPB_BIT_WAITERS) == 0 && !atomic_cmpset_int(&m->busy_lock, x, x | VPB_BIT_WAITERS))) { vm_page_unlock(m); return; } msleep(m, vm_page_lockptr(m), PVM | PDROP, wmesg, 0); } /* * vm_page_trysbusy: * * Try to shared busy a page. * If the operation succeeds 1 is returned otherwise 0. * The operation never sleeps. */ int vm_page_trysbusy(vm_page_t m) { u_int x; for (;;) { x = m->busy_lock; if ((x & VPB_BIT_SHARED) == 0) return (0); if (atomic_cmpset_acq_int(&m->busy_lock, x, x + VPB_ONE_SHARER)) return (1); } } static void vm_page_xunbusy_locked(vm_page_t m) { vm_page_assert_xbusied(m); vm_page_assert_locked(m); atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED); /* There is a waiter, do wakeup() instead of vm_page_flash(). */ wakeup(m); } void vm_page_xunbusy_maybelocked(vm_page_t m) { bool lockacq; vm_page_assert_xbusied(m); /* * Fast path for unbusy. If it succeeds, we know that there * are no waiters, so we do not need a wakeup. */ if (atomic_cmpset_rel_int(&m->busy_lock, VPB_SINGLE_EXCLUSIVER, VPB_UNBUSIED)) return; lockacq = !mtx_owned(vm_page_lockptr(m)); if (lockacq) vm_page_lock(m); vm_page_xunbusy_locked(m); if (lockacq) vm_page_unlock(m); } /* * vm_page_xunbusy_hard: * * Called after the first try the exclusive unbusy of a page failed. * It is assumed that the waiters bit is on. */ void vm_page_xunbusy_hard(vm_page_t m) { vm_page_assert_xbusied(m); vm_page_lock(m); vm_page_xunbusy_locked(m); vm_page_unlock(m); } /* * vm_page_flash: * * Wakeup anyone waiting for the page. * The ownership bits do not change. * * The given page must be locked. */ void vm_page_flash(vm_page_t m) { u_int x; vm_page_lock_assert(m, MA_OWNED); for (;;) { x = m->busy_lock; if ((x & VPB_BIT_WAITERS) == 0) return; if (atomic_cmpset_int(&m->busy_lock, x, x & (~VPB_BIT_WAITERS))) break; } wakeup(m); } /* * Avoid releasing and reacquiring the same page lock. */ void vm_page_change_lock(vm_page_t m, struct mtx **mtx) { struct mtx *mtx1; mtx1 = vm_page_lockptr(m); if (*mtx == mtx1) return; if (*mtx != NULL) mtx_unlock(*mtx); *mtx = mtx1; mtx_lock(mtx1); } /* * Keep page from being freed by the page daemon * much of the same effect as wiring, except much lower * overhead and should be used only for *very* temporary * holding ("wiring"). */ void vm_page_hold(vm_page_t mem) { vm_page_lock_assert(mem, MA_OWNED); mem->hold_count++; } void vm_page_unhold(vm_page_t mem) { vm_page_lock_assert(mem, MA_OWNED); KASSERT(mem->hold_count >= 1, ("vm_page_unhold: hold count < 0!!!")); --mem->hold_count; if (mem->hold_count == 0 && (mem->flags & PG_UNHOLDFREE) != 0) vm_page_free_toq(mem); } /* * vm_page_unhold_pages: * * Unhold each of the pages that is referenced by the given array. */ void vm_page_unhold_pages(vm_page_t *ma, int count) { struct mtx *mtx; mtx = NULL; for (; count != 0; count--) { vm_page_change_lock(*ma, &mtx); vm_page_unhold(*ma); ma++; } if (mtx != NULL) mtx_unlock(mtx); } vm_page_t PHYS_TO_VM_PAGE(vm_paddr_t pa) { vm_page_t m; #ifdef VM_PHYSSEG_SPARSE m = vm_phys_paddr_to_vm_page(pa); if (m == NULL) m = vm_phys_fictitious_to_vm_page(pa); return (m); #elif defined(VM_PHYSSEG_DENSE) long pi; pi = atop(pa); if (pi >= first_page && (pi - first_page) < vm_page_array_size) { m = &vm_page_array[pi - first_page]; return (m); } return (vm_phys_fictitious_to_vm_page(pa)); #else #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." #endif } /* * vm_page_getfake: * * Create a fictitious page with the specified physical address and * memory attribute. The memory attribute is the only the machine- * dependent aspect of a fictitious page that must be initialized. */ vm_page_t vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr) { vm_page_t m; m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO); vm_page_initfake(m, paddr, memattr); return (m); } void vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) { if ((m->flags & PG_FICTITIOUS) != 0) { /* * The page's memattr might have changed since the * previous initialization. Update the pmap to the * new memattr. */ goto memattr; } m->phys_addr = paddr; m->queue = PQ_NONE; /* Fictitious pages don't use "segind". */ m->flags = PG_FICTITIOUS; /* Fictitious pages don't use "order" or "pool". */ m->oflags = VPO_UNMANAGED; m->busy_lock = VPB_SINGLE_EXCLUSIVER; m->wire_count = 1; pmap_page_init(m); memattr: pmap_page_set_memattr(m, memattr); } /* * vm_page_putfake: * * Release a fictitious page. */ void vm_page_putfake(vm_page_t m) { KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m)); KASSERT((m->flags & PG_FICTITIOUS) != 0, ("vm_page_putfake: bad page %p", m)); uma_zfree(fakepg_zone, m); } /* * vm_page_updatefake: * * Update the given fictitious page to the specified physical address and * memory attribute. */ void vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) { KASSERT((m->flags & PG_FICTITIOUS) != 0, ("vm_page_updatefake: bad page %p", m)); m->phys_addr = paddr; pmap_page_set_memattr(m, memattr); } /* * vm_page_free: * * Free a page. */ void vm_page_free(vm_page_t m) { m->flags &= ~PG_ZERO; vm_page_free_toq(m); } /* * vm_page_free_zero: * * Free a page to the zerod-pages queue */ void vm_page_free_zero(vm_page_t m) { m->flags |= PG_ZERO; vm_page_free_toq(m); } /* * Unbusy and handle the page queueing for a page from a getpages request that * was optionally read ahead or behind. */ void vm_page_readahead_finish(vm_page_t m) { /* We shouldn't put invalid pages on queues. */ KASSERT(m->valid != 0, ("%s: %p is invalid", __func__, m)); /* * Since the page is not the actually needed one, whether it should * be activated or deactivated is not obvious. Empirical results * have shown that deactivating the page is usually the best choice, * unless the page is wanted by another thread. */ vm_page_lock(m); if ((m->busy_lock & VPB_BIT_WAITERS) != 0) vm_page_activate(m); else vm_page_deactivate(m); vm_page_unlock(m); vm_page_xunbusy(m); } /* * vm_page_sleep_if_busy: * * Sleep and release the page queues lock if the page is busied. * Returns TRUE if the thread slept. * * The given page must be unlocked and object containing it must * be locked. */ int vm_page_sleep_if_busy(vm_page_t m, const char *msg) { vm_object_t obj; vm_page_lock_assert(m, MA_NOTOWNED); VM_OBJECT_ASSERT_WLOCKED(m->object); if (vm_page_busied(m)) { /* * The page-specific object must be cached because page * identity can change during the sleep, causing the * re-lock of a different object. * It is assumed that a reference to the object is already * held by the callers. */ obj = m->object; vm_page_lock(m); VM_OBJECT_WUNLOCK(obj); vm_page_busy_sleep(m, msg, false); VM_OBJECT_WLOCK(obj); return (TRUE); } return (FALSE); } /* * vm_page_dirty_KBI: [ internal use only ] * * Set all bits in the page's dirty field. * * The object containing the specified page must be locked if the * call is made from the machine-independent layer. * * See vm_page_clear_dirty_mask(). * * This function should only be called by vm_page_dirty(). */ void vm_page_dirty_KBI(vm_page_t m) { /* Refer to this operation by its public name. */ KASSERT(m->valid == VM_PAGE_BITS_ALL, ("vm_page_dirty: page is invalid!")); m->dirty = VM_PAGE_BITS_ALL; } /* * vm_page_insert: [ internal use only ] * * Inserts the given mem entry into the object and object list. * * The object must be locked. */ int vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex) { vm_page_t mpred; VM_OBJECT_ASSERT_WLOCKED(object); mpred = vm_radix_lookup_le(&object->rtree, pindex); return (vm_page_insert_after(m, object, pindex, mpred)); } /* * vm_page_insert_after: * * Inserts the page "m" into the specified object at offset "pindex". * * The page "mpred" must immediately precede the offset "pindex" within * the specified object. * * The object must be locked. */ static int vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex, vm_page_t mpred) { vm_page_t msucc; VM_OBJECT_ASSERT_WLOCKED(object); KASSERT(m->object == NULL, ("vm_page_insert_after: page already inserted")); if (mpred != NULL) { KASSERT(mpred->object == object, ("vm_page_insert_after: object doesn't contain mpred")); KASSERT(mpred->pindex < pindex, ("vm_page_insert_after: mpred doesn't precede pindex")); msucc = TAILQ_NEXT(mpred, listq); } else msucc = TAILQ_FIRST(&object->memq); if (msucc != NULL) KASSERT(msucc->pindex > pindex, ("vm_page_insert_after: msucc doesn't succeed pindex")); /* * Record the object/offset pair in this page */ m->object = object; m->pindex = pindex; /* * Now link into the object's ordered list of backed pages. */ if (vm_radix_insert(&object->rtree, m)) { m->object = NULL; m->pindex = 0; return (1); } vm_page_insert_radixdone(m, object, mpred); return (0); } /* * vm_page_insert_radixdone: * * Complete page "m" insertion into the specified object after the * radix trie hooking. * * The page "mpred" must precede the offset "m->pindex" within the * specified object. * * The object must be locked. */ static void vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred) { VM_OBJECT_ASSERT_WLOCKED(object); KASSERT(object != NULL && m->object == object, ("vm_page_insert_radixdone: page %p has inconsistent object", m)); if (mpred != NULL) { KASSERT(mpred->object == object, ("vm_page_insert_after: object doesn't contain mpred")); KASSERT(mpred->pindex < m->pindex, ("vm_page_insert_after: mpred doesn't precede pindex")); } if (mpred != NULL) TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq); else TAILQ_INSERT_HEAD(&object->memq, m, listq); /* * Show that the object has one more resident page. */ object->resident_page_count++; /* * Hold the vnode until the last page is released. */ if (object->resident_page_count == 1 && object->type == OBJT_VNODE) vhold(object->handle); /* * Since we are inserting a new and possibly dirty page, * update the object's OBJ_MIGHTBEDIRTY flag. */ if (pmap_page_is_write_mapped(m)) vm_object_set_writeable_dirty(object); } /* * vm_page_remove: * * Removes the specified page from its containing object, but does not * invalidate any backing storage. * * The object must be locked. The page must be locked if it is managed. */ void vm_page_remove(vm_page_t m) { vm_object_t object; vm_page_t mrem; if ((m->oflags & VPO_UNMANAGED) == 0) vm_page_assert_locked(m); if ((object = m->object) == NULL) return; VM_OBJECT_ASSERT_WLOCKED(object); if (vm_page_xbusied(m)) vm_page_xunbusy_maybelocked(m); mrem = vm_radix_remove(&object->rtree, m->pindex); KASSERT(mrem == m, ("removed page %p, expected page %p", mrem, m)); /* * Now remove from the object's list of backed pages. */ TAILQ_REMOVE(&object->memq, m, listq); /* * And show that the object has one fewer resident page. */ object->resident_page_count--; /* * The vnode may now be recycled. */ if (object->resident_page_count == 0 && object->type == OBJT_VNODE) vdrop(object->handle); m->object = NULL; } /* * vm_page_lookup: * * Returns the page associated with the object/offset * pair specified; if none is found, NULL is returned. * * The object must be locked. */ vm_page_t vm_page_lookup(vm_object_t object, vm_pindex_t pindex) { VM_OBJECT_ASSERT_LOCKED(object); return (vm_radix_lookup(&object->rtree, pindex)); } /* * vm_page_find_least: * * Returns the page associated with the object with least pindex * greater than or equal to the parameter pindex, or NULL. * * The object must be locked. */ vm_page_t vm_page_find_least(vm_object_t object, vm_pindex_t pindex) { vm_page_t m; VM_OBJECT_ASSERT_LOCKED(object); if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex) m = vm_radix_lookup_ge(&object->rtree, pindex); return (m); } /* * Returns the given page's successor (by pindex) within the object if it is * resident; if none is found, NULL is returned. * * The object must be locked. */ vm_page_t vm_page_next(vm_page_t m) { vm_page_t next; VM_OBJECT_ASSERT_LOCKED(m->object); if ((next = TAILQ_NEXT(m, listq)) != NULL) { MPASS(next->object == m->object); if (next->pindex != m->pindex + 1) next = NULL; } return (next); } /* * Returns the given page's predecessor (by pindex) within the object if it is * resident; if none is found, NULL is returned. * * The object must be locked. */ vm_page_t vm_page_prev(vm_page_t m) { vm_page_t prev; VM_OBJECT_ASSERT_LOCKED(m->object); if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL) { MPASS(prev->object == m->object); if (prev->pindex != m->pindex - 1) prev = NULL; } return (prev); } /* * Uses the page mnew as a replacement for an existing page at index * pindex which must be already present in the object. * * The existing page must not be on a paging queue. */ vm_page_t vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex) { vm_page_t mold; VM_OBJECT_ASSERT_WLOCKED(object); KASSERT(mnew->object == NULL, ("vm_page_replace: page %p already in object", mnew)); KASSERT(mnew->queue == PQ_NONE, ("vm_page_replace: new page %p is on a paging queue", mnew)); /* * This function mostly follows vm_page_insert() and * vm_page_remove() without the radix, object count and vnode * dance. Double check such functions for more comments. */ mnew->object = object; mnew->pindex = pindex; mold = vm_radix_replace(&object->rtree, mnew); KASSERT(mold->queue == PQ_NONE, ("vm_page_replace: old page %p is on a paging queue", mold)); /* Keep the resident page list in sorted order. */ TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq); TAILQ_REMOVE(&object->memq, mold, listq); mold->object = NULL; vm_page_xunbusy_maybelocked(mold); /* * The object's resident_page_count does not change because we have * swapped one page for another, but OBJ_MIGHTBEDIRTY. */ if (pmap_page_is_write_mapped(mnew)) vm_object_set_writeable_dirty(object); return (mold); } /* * vm_page_rename: * * Move the given memory entry from its * current object to the specified target object/offset. * * Note: swap associated with the page must be invalidated by the move. We * have to do this for several reasons: (1) we aren't freeing the * page, (2) we are dirtying the page, (3) the VM system is probably * moving the page from object A to B, and will then later move * the backing store from A to B and we can't have a conflict. * * Note: we *always* dirty the page. It is necessary both for the * fact that we moved it, and because we may be invalidating * swap. * * The objects must be locked. */ int vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex) { vm_page_t mpred; vm_pindex_t opidx; VM_OBJECT_ASSERT_WLOCKED(new_object); mpred = vm_radix_lookup_le(&new_object->rtree, new_pindex); KASSERT(mpred == NULL || mpred->pindex != new_pindex, ("vm_page_rename: pindex already renamed")); /* * Create a custom version of vm_page_insert() which does not depend * by m_prev and can cheat on the implementation aspects of the * function. */ opidx = m->pindex; m->pindex = new_pindex; if (vm_radix_insert(&new_object->rtree, m)) { m->pindex = opidx; return (1); } /* * The operation cannot fail anymore. The removal must happen before * the listq iterator is tainted. */ m->pindex = opidx; vm_page_lock(m); vm_page_remove(m); /* Return back to the new pindex to complete vm_page_insert(). */ m->pindex = new_pindex; m->object = new_object; vm_page_unlock(m); vm_page_insert_radixdone(m, new_object, mpred); vm_page_dirty(m); return (0); } /* * vm_page_alloc: * * Allocate and return a page that is associated with the specified * object and offset pair. By default, this page is exclusive busied. * * The caller must always specify an allocation class. * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * * optional allocation flags: * VM_ALLOC_COUNT(number) the number of additional pages that the caller * intends to allocate * VM_ALLOC_NOBUSY do not exclusive busy the page * VM_ALLOC_NODUMP do not include the page in a kernel core dump * VM_ALLOC_NOOBJ page is not associated with an object and * should not be exclusive busy * VM_ALLOC_SBUSY shared busy the allocated page * VM_ALLOC_WIRED wire the allocated page * VM_ALLOC_ZERO prefer a zeroed page */ vm_page_t vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req) { return (vm_page_alloc_after(object, pindex, req, object != NULL ? vm_radix_lookup_le(&object->rtree, pindex) : NULL)); } vm_page_t vm_page_alloc_domain(vm_object_t object, vm_pindex_t pindex, int domain, int req) { return (vm_page_alloc_domain_after(object, pindex, domain, req, object != NULL ? vm_radix_lookup_le(&object->rtree, pindex) : NULL)); } /* * Allocate a page in the specified object with the given page index. To * optimize insertion of the page into the object, the caller must also specifiy * the resident page in the object with largest index smaller than the given * page index, or NULL if no such page exists. */ vm_page_t vm_page_alloc_after(vm_object_t object, vm_pindex_t pindex, int req, vm_page_t mpred) { struct vm_domainset_iter di; vm_page_t m; int domain; vm_domainset_iter_page_init(&di, object, &domain, &req); do { m = vm_page_alloc_domain_after(object, pindex, domain, req, mpred); if (m != NULL) break; } while (vm_domainset_iter_page(&di, &domain, &req) == 0); return (m); } /* * Returns true if the number of free pages exceeds the minimum * for the request class and false otherwise. */ int vm_domain_available(struct vm_domain *vmd, int req, int npages) { vm_domain_free_assert_locked(vmd); req = req & VM_ALLOC_CLASS_MASK; /* * The page daemon is allowed to dig deeper into the free page list. */ if (curproc == pageproc && req != VM_ALLOC_INTERRUPT) req = VM_ALLOC_SYSTEM; if (vmd->vmd_free_count >= npages + vmd->vmd_free_reserved || (req == VM_ALLOC_SYSTEM && vmd->vmd_free_count >= npages + vmd->vmd_interrupt_free_min) || (req == VM_ALLOC_INTERRUPT && vmd->vmd_free_count >= npages)) return (1); return (0); } vm_page_t vm_page_alloc_domain_after(vm_object_t object, vm_pindex_t pindex, int domain, int req, vm_page_t mpred) { struct vm_domain *vmd; vm_page_t m; int flags; KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), ("inconsistent object(%p)/req(%x)", object, req)); KASSERT(object == NULL || (req & VM_ALLOC_WAITOK) == 0, ("Can't sleep and retry object insertion.")); KASSERT(mpred == NULL || mpred->pindex < pindex, ("mpred %p doesn't precede pindex 0x%jx", mpred, (uintmax_t)pindex)); if (object != NULL) VM_OBJECT_ASSERT_WLOCKED(object); again: m = NULL; #if VM_NRESERVLEVEL > 0 if (vm_object_reserv(object) && (m = vm_reserv_extend(req, object, pindex, domain, mpred)) != NULL) { domain = vm_phys_domain(m); vmd = VM_DOMAIN(domain); goto found; } #endif vmd = VM_DOMAIN(domain); vm_domain_free_lock(vmd); if (vm_domain_available(vmd, req, 1)) { /* * Can we allocate the page from a reservation? */ #if VM_NRESERVLEVEL > 0 if (!vm_object_reserv(object) || (m = vm_reserv_alloc_page(object, pindex, domain, mpred)) == NULL) #endif { /* * If not, allocate it from the free page queues. */ m = vm_phys_alloc_pages(domain, object != NULL ? VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 0); #if VM_NRESERVLEVEL > 0 if (m == NULL && vm_reserv_reclaim_inactive(domain)) { m = vm_phys_alloc_pages(domain, object != NULL ? VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 0); } #endif } } if (m != NULL) vm_domain_freecnt_dec(vmd, 1); vm_domain_free_unlock(vmd); if (m == NULL) { /* * Not allocatable, give up. */ if (vm_domain_alloc_fail(vmd, object, req)) goto again; return (NULL); } /* * At this point we had better have found a good page. */ KASSERT(m != NULL, ("missing page")); #if VM_NRESERVLEVEL > 0 found: #endif vm_page_alloc_check(m); /* * Initialize the page. Only the PG_ZERO flag is inherited. */ flags = 0; if ((req & VM_ALLOC_ZERO) != 0) flags = PG_ZERO; flags &= m->flags; if ((req & VM_ALLOC_NODUMP) != 0) flags |= PG_NODUMP; m->flags = flags; m->aflags = 0; m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ? VPO_UNMANAGED : 0; m->busy_lock = VPB_UNBUSIED; if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0) m->busy_lock = VPB_SINGLE_EXCLUSIVER; if ((req & VM_ALLOC_SBUSY) != 0) m->busy_lock = VPB_SHARERS_WORD(1); if (req & VM_ALLOC_WIRED) { /* * The page lock is not required for wiring a page until that * page is inserted into the object. */ vm_wire_add(1); m->wire_count = 1; } m->act_count = 0; if (object != NULL) { if (vm_page_insert_after(m, object, pindex, mpred)) { if (req & VM_ALLOC_WIRED) { vm_wire_sub(1); m->wire_count = 0; } KASSERT(m->object == NULL, ("page %p has object", m)); m->oflags = VPO_UNMANAGED; m->busy_lock = VPB_UNBUSIED; /* Don't change PG_ZERO. */ vm_page_free_toq(m); if (req & VM_ALLOC_WAITFAIL) { VM_OBJECT_WUNLOCK(object); vm_radix_wait(); VM_OBJECT_WLOCK(object); } return (NULL); } /* Ignore device objects; the pager sets "memattr" for them. */ if (object->memattr != VM_MEMATTR_DEFAULT && (object->flags & OBJ_FICTITIOUS) == 0) pmap_page_set_memattr(m, object->memattr); } else m->pindex = pindex; return (m); } /* * vm_page_alloc_contig: * * Allocate a contiguous set of physical pages of the given size "npages" * from the free lists. All of the physical pages must be at or above * the given physical address "low" and below the given physical address * "high". The given value "alignment" determines the alignment of the * first physical page in the set. If the given value "boundary" is * non-zero, then the set of physical pages cannot cross any physical * address boundary that is a multiple of that value. Both "alignment" * and "boundary" must be a power of two. * * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT, * then the memory attribute setting for the physical pages is configured * to the object's memory attribute setting. Otherwise, the memory * attribute setting for the physical pages is configured to "memattr", * overriding the object's memory attribute setting. However, if the * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the * memory attribute setting for the physical pages cannot be configured * to VM_MEMATTR_DEFAULT. * * The specified object may not contain fictitious pages. * * The caller must always specify an allocation class. * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * * optional allocation flags: * VM_ALLOC_NOBUSY do not exclusive busy the page * VM_ALLOC_NODUMP do not include the page in a kernel core dump * VM_ALLOC_NOOBJ page is not associated with an object and * should not be exclusive busy * VM_ALLOC_SBUSY shared busy the allocated page * VM_ALLOC_WIRED wire the allocated page * VM_ALLOC_ZERO prefer a zeroed page */ vm_page_t vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, vm_memattr_t memattr) { struct vm_domainset_iter di; vm_page_t m; int domain; vm_domainset_iter_page_init(&di, object, &domain, &req); do { m = vm_page_alloc_contig_domain(object, pindex, domain, req, npages, low, high, alignment, boundary, memattr); if (m != NULL) break; } while (vm_domainset_iter_page(&di, &domain, &req) == 0); return (m); } vm_page_t vm_page_alloc_contig_domain(vm_object_t object, vm_pindex_t pindex, int domain, int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, vm_memattr_t memattr) { struct vm_domain *vmd; vm_page_t m, m_ret, mpred; u_int busy_lock, flags, oflags; mpred = NULL; /* XXX: pacify gcc */ KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), ("vm_page_alloc_contig: inconsistent object(%p)/req(%x)", object, req)); KASSERT(object == NULL || (req & VM_ALLOC_WAITOK) == 0, ("Can't sleep and retry object insertion.")); if (object != NULL) { VM_OBJECT_ASSERT_WLOCKED(object); KASSERT((object->flags & OBJ_FICTITIOUS) == 0, ("vm_page_alloc_contig: object %p has fictitious pages", object)); } KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); if (object != NULL) { mpred = vm_radix_lookup_le(&object->rtree, pindex); KASSERT(mpred == NULL || mpred->pindex != pindex, ("vm_page_alloc_contig: pindex already allocated")); } /* * Can we allocate the pages without the number of free pages falling * below the lower bound for the allocation class? */ again: #if VM_NRESERVLEVEL > 0 if (vm_object_reserv(object) && (m_ret = vm_reserv_extend_contig(req, object, pindex, domain, npages, low, high, alignment, boundary, mpred)) != NULL) { domain = vm_phys_domain(m_ret); vmd = VM_DOMAIN(domain); goto found; } #endif m_ret = NULL; vmd = VM_DOMAIN(domain); vm_domain_free_lock(vmd); if (vm_domain_available(vmd, req, npages)) { /* * Can we allocate the pages from a reservation? */ #if VM_NRESERVLEVEL > 0 retry: if (!vm_object_reserv(object) || (m_ret = vm_reserv_alloc_contig(object, pindex, domain, npages, low, high, alignment, boundary, mpred)) == NULL) #endif /* * If not, allocate them from the free page queues. */ m_ret = vm_phys_alloc_contig(domain, npages, low, high, alignment, boundary); #if VM_NRESERVLEVEL > 0 if (m_ret == NULL && vm_reserv_reclaim_contig( domain, npages, low, high, alignment, boundary)) goto retry; #endif } if (m_ret != NULL) vm_domain_freecnt_dec(vmd, npages); vm_domain_free_unlock(vmd); if (m_ret == NULL) { if (vm_domain_alloc_fail(vmd, object, req)) goto again; return (NULL); } #if VM_NRESERVLEVEL > 0 found: #endif for (m = m_ret; m < &m_ret[npages]; m++) vm_page_alloc_check(m); /* * Initialize the pages. Only the PG_ZERO flag is inherited. */ flags = 0; if ((req & VM_ALLOC_ZERO) != 0) flags = PG_ZERO; if ((req & VM_ALLOC_NODUMP) != 0) flags |= PG_NODUMP; oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ? VPO_UNMANAGED : 0; busy_lock = VPB_UNBUSIED; if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0) busy_lock = VPB_SINGLE_EXCLUSIVER; if ((req & VM_ALLOC_SBUSY) != 0) busy_lock = VPB_SHARERS_WORD(1); if ((req & VM_ALLOC_WIRED) != 0) vm_wire_add(npages); if (object != NULL) { if (object->memattr != VM_MEMATTR_DEFAULT && memattr == VM_MEMATTR_DEFAULT) memattr = object->memattr; } for (m = m_ret; m < &m_ret[npages]; m++) { m->aflags = 0; m->flags = (m->flags | PG_NODUMP) & flags; m->busy_lock = busy_lock; if ((req & VM_ALLOC_WIRED) != 0) m->wire_count = 1; m->act_count = 0; m->oflags = oflags; if (object != NULL) { if (vm_page_insert_after(m, object, pindex, mpred)) { if ((req & VM_ALLOC_WIRED) != 0) vm_wire_sub(npages); KASSERT(m->object == NULL, ("page %p has object", m)); mpred = m; for (m = m_ret; m < &m_ret[npages]; m++) { if (m <= mpred && (req & VM_ALLOC_WIRED) != 0) m->wire_count = 0; m->oflags = VPO_UNMANAGED; m->busy_lock = VPB_UNBUSIED; /* Don't change PG_ZERO. */ vm_page_free_toq(m); } if (req & VM_ALLOC_WAITFAIL) { VM_OBJECT_WUNLOCK(object); vm_radix_wait(); VM_OBJECT_WLOCK(object); } return (NULL); } mpred = m; } else m->pindex = pindex; if (memattr != VM_MEMATTR_DEFAULT) pmap_page_set_memattr(m, memattr); pindex++; } return (m_ret); } /* * Check a page that has been freshly dequeued from a freelist. */ static void vm_page_alloc_check(vm_page_t m) { KASSERT(m->object == NULL, ("page %p has object", m)); KASSERT(m->queue == PQ_NONE, ("page %p has unexpected queue %d", m, m->queue)); KASSERT(!vm_page_held(m), ("page %p is held", m)); KASSERT(!vm_page_busied(m), ("page %p is busy", m)); KASSERT(m->dirty == 0, ("page %p is dirty", m)); KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, ("page %p has unexpected memattr %d", m, pmap_page_get_memattr(m))); KASSERT(m->valid == 0, ("free page %p is valid", m)); } /* * vm_page_alloc_freelist: * * Allocate a physical page from the specified free page list. * * The caller must always specify an allocation class. * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * * optional allocation flags: * VM_ALLOC_COUNT(number) the number of additional pages that the caller * intends to allocate * VM_ALLOC_WIRED wire the allocated page * VM_ALLOC_ZERO prefer a zeroed page */ vm_page_t vm_page_alloc_freelist(int freelist, int req) { struct vm_domainset_iter di; vm_page_t m; int domain; vm_domainset_iter_page_init(&di, kernel_object, &domain, &req); do { m = vm_page_alloc_freelist_domain(domain, freelist, req); if (m != NULL) break; } while (vm_domainset_iter_page(&di, &domain, &req) == 0); return (m); } vm_page_t vm_page_alloc_freelist_domain(int domain, int freelist, int req) { struct vm_domain *vmd; vm_page_t m; u_int flags; /* * Do not allocate reserved pages unless the req has asked for it. */ vmd = VM_DOMAIN(domain); again: vm_domain_free_lock(vmd); if (vm_domain_available(vmd, req, 1)) m = vm_phys_alloc_freelist_pages(domain, freelist, VM_FREEPOOL_DIRECT, 0); if (m != NULL) vm_domain_freecnt_dec(vmd, 1); vm_domain_free_unlock(vmd); if (m == NULL) { if (vm_domain_alloc_fail(vmd, NULL, req)) goto again; return (NULL); } vm_page_alloc_check(m); /* * Initialize the page. Only the PG_ZERO flag is inherited. */ m->aflags = 0; flags = 0; if ((req & VM_ALLOC_ZERO) != 0) flags = PG_ZERO; m->flags &= flags; if ((req & VM_ALLOC_WIRED) != 0) { /* * The page lock is not required for wiring a page that does * not belong to an object. */ vm_wire_add(1); m->wire_count = 1; } /* Unmanaged pages don't use "act_count". */ m->oflags = VPO_UNMANAGED; return (m); } #define VPSC_ANY 0 /* No restrictions. */ #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */ #define VPSC_NOSUPER 2 /* Skip superpages. */ /* * vm_page_scan_contig: * * Scan vm_page_array[] between the specified entries "m_start" and * "m_end" for a run of contiguous physical pages that satisfy the * specified conditions, and return the lowest page in the run. The * specified "alignment" determines the alignment of the lowest physical * page in the run. If the specified "boundary" is non-zero, then the * run of physical pages cannot span a physical address that is a * multiple of "boundary". * * "m_end" is never dereferenced, so it need not point to a vm_page * structure within vm_page_array[]. * * "npages" must be greater than zero. "m_start" and "m_end" must not * span a hole (or discontiguity) in the physical address space. Both * "alignment" and "boundary" must be a power of two. */ vm_page_t vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end, u_long alignment, vm_paddr_t boundary, int options) { struct mtx *m_mtx; vm_object_t object; vm_paddr_t pa; vm_page_t m, m_run; #if VM_NRESERVLEVEL > 0 int level; #endif int m_inc, order, run_ext, run_len; KASSERT(npages > 0, ("npages is 0")); KASSERT(powerof2(alignment), ("alignment is not a power of 2")); KASSERT(powerof2(boundary), ("boundary is not a power of 2")); m_run = NULL; run_len = 0; m_mtx = NULL; for (m = m_start; m < m_end && run_len < npages; m += m_inc) { KASSERT((m->flags & PG_MARKER) == 0, ("page %p is PG_MARKER", m)); KASSERT((m->flags & PG_FICTITIOUS) == 0 || m->wire_count == 1, ("fictitious page %p has invalid wire count", m)); /* * If the current page would be the start of a run, check its * physical address against the end, alignment, and boundary * conditions. If it doesn't satisfy these conditions, either * terminate the scan or advance to the next page that * satisfies the failed condition. */ if (run_len == 0) { KASSERT(m_run == NULL, ("m_run != NULL")); if (m + npages > m_end) break; pa = VM_PAGE_TO_PHYS(m); if ((pa & (alignment - 1)) != 0) { m_inc = atop(roundup2(pa, alignment) - pa); continue; } if (rounddown2(pa ^ (pa + ptoa(npages) - 1), boundary) != 0) { m_inc = atop(roundup2(pa, boundary) - pa); continue; } } else KASSERT(m_run != NULL, ("m_run == NULL")); vm_page_change_lock(m, &m_mtx); m_inc = 1; retry: if (vm_page_held(m)) run_ext = 0; #if VM_NRESERVLEVEL > 0 else if ((level = vm_reserv_level(m)) >= 0 && (options & VPSC_NORESERV) != 0) { run_ext = 0; /* Advance to the end of the reservation. */ pa = VM_PAGE_TO_PHYS(m); m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) - pa); } #endif else if ((object = m->object) != NULL) { /* * The page is considered eligible for relocation if * and only if it could be laundered or reclaimed by * the page daemon. */ if (!VM_OBJECT_TRYRLOCK(object)) { mtx_unlock(m_mtx); VM_OBJECT_RLOCK(object); mtx_lock(m_mtx); if (m->object != object) { /* * The page may have been freed. */ VM_OBJECT_RUNLOCK(object); goto retry; } else if (vm_page_held(m)) { run_ext = 0; goto unlock; } } KASSERT((m->flags & PG_UNHOLDFREE) == 0, ("page %p is PG_UNHOLDFREE", m)); /* Don't care: PG_NODUMP, PG_ZERO. */ if (object->type != OBJT_DEFAULT && object->type != OBJT_SWAP && object->type != OBJT_VNODE) { run_ext = 0; #if VM_NRESERVLEVEL > 0 } else if ((options & VPSC_NOSUPER) != 0 && (level = vm_reserv_level_iffullpop(m)) >= 0) { run_ext = 0; /* Advance to the end of the superpage. */ pa = VM_PAGE_TO_PHYS(m); m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) - pa); #endif } else if (object->memattr == VM_MEMATTR_DEFAULT && m->queue != PQ_NONE && !vm_page_busied(m)) { /* * The page is allocated but eligible for * relocation. Extend the current run by one * page. */ KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, ("page %p has an unexpected memattr", m)); KASSERT((m->oflags & (VPO_SWAPINPROG | VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, ("page %p has unexpected oflags", m)); /* Don't care: VPO_NOSYNC. */ run_ext = 1; } else run_ext = 0; unlock: VM_OBJECT_RUNLOCK(object); #if VM_NRESERVLEVEL > 0 } else if (level >= 0) { /* * The page is reserved but not yet allocated. In * other words, it is still free. Extend the current * run by one page. */ run_ext = 1; #endif } else if ((order = m->order) < VM_NFREEORDER) { /* * The page is enqueued in the physical memory * allocator's free page queues. Moreover, it is the * first page in a power-of-two-sized run of * contiguous free pages. Add these pages to the end * of the current run, and jump ahead. */ run_ext = 1 << order; m_inc = 1 << order; } else { /* * Skip the page for one of the following reasons: (1) * It is enqueued in the physical memory allocator's * free page queues. However, it is not the first * page in a run of contiguous free pages. (This case * rarely occurs because the scan is performed in * ascending order.) (2) It is not reserved, and it is * transitioning from free to allocated. (Conversely, * the transition from allocated to free for managed * pages is blocked by the page lock.) (3) It is * allocated but not contained by an object and not * wired, e.g., allocated by Xen's balloon driver. */ run_ext = 0; } /* * Extend or reset the current run of pages. */ if (run_ext > 0) { if (run_len == 0) m_run = m; run_len += run_ext; } else { if (run_len > 0) { m_run = NULL; run_len = 0; } } } if (m_mtx != NULL) mtx_unlock(m_mtx); if (run_len >= npages) return (m_run); return (NULL); } /* * vm_page_reclaim_run: * * Try to relocate each of the allocated virtual pages within the * specified run of physical pages to a new physical address. Free the * physical pages underlying the relocated virtual pages. A virtual page * is relocatable if and only if it could be laundered or reclaimed by * the page daemon. Whenever possible, a virtual page is relocated to a * physical address above "high". * * Returns 0 if every physical page within the run was already free or * just freed by a successful relocation. Otherwise, returns a non-zero * value indicating why the last attempt to relocate a virtual page was * unsuccessful. * * "req_class" must be an allocation class. */ static int vm_page_reclaim_run(int req_class, int domain, u_long npages, vm_page_t m_run, vm_paddr_t high) { struct vm_domain *vmd; struct mtx *m_mtx; struct spglist free; vm_object_t object; vm_paddr_t pa; vm_page_t m, m_end, m_new; int error, order, req; KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class, ("req_class is not an allocation class")); SLIST_INIT(&free); error = 0; m = m_run; m_end = m_run + npages; m_mtx = NULL; for (; error == 0 && m < m_end; m++) { KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, ("page %p is PG_FICTITIOUS or PG_MARKER", m)); /* * Avoid releasing and reacquiring the same page lock. */ vm_page_change_lock(m, &m_mtx); retry: if (vm_page_held(m)) error = EBUSY; else if ((object = m->object) != NULL) { /* * The page is relocated if and only if it could be * laundered or reclaimed by the page daemon. */ if (!VM_OBJECT_TRYWLOCK(object)) { mtx_unlock(m_mtx); VM_OBJECT_WLOCK(object); mtx_lock(m_mtx); if (m->object != object) { /* * The page may have been freed. */ VM_OBJECT_WUNLOCK(object); goto retry; } else if (vm_page_held(m)) { error = EBUSY; goto unlock; } } KASSERT((m->flags & PG_UNHOLDFREE) == 0, ("page %p is PG_UNHOLDFREE", m)); /* Don't care: PG_NODUMP, PG_ZERO. */ if (object->type != OBJT_DEFAULT && object->type != OBJT_SWAP && object->type != OBJT_VNODE) error = EINVAL; else if (object->memattr != VM_MEMATTR_DEFAULT) error = EINVAL; else if (m->queue != PQ_NONE && !vm_page_busied(m)) { KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, ("page %p has an unexpected memattr", m)); KASSERT((m->oflags & (VPO_SWAPINPROG | VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, ("page %p has unexpected oflags", m)); /* Don't care: VPO_NOSYNC. */ if (m->valid != 0) { /* * First, try to allocate a new page * that is above "high". Failing * that, try to allocate a new page * that is below "m_run". Allocate * the new page between the end of * "m_run" and "high" only as a last * resort. */ req = req_class | VM_ALLOC_NOOBJ; if ((m->flags & PG_NODUMP) != 0) req |= VM_ALLOC_NODUMP; if (trunc_page(high) != ~(vm_paddr_t)PAGE_MASK) { m_new = vm_page_alloc_contig( NULL, 0, req, 1, round_page(high), ~(vm_paddr_t)0, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT); } else m_new = NULL; if (m_new == NULL) { pa = VM_PAGE_TO_PHYS(m_run); m_new = vm_page_alloc_contig( NULL, 0, req, 1, 0, pa - 1, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT); } if (m_new == NULL) { pa += ptoa(npages); m_new = vm_page_alloc_contig( NULL, 0, req, 1, pa, high, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT); } if (m_new == NULL) { error = ENOMEM; goto unlock; } KASSERT(m_new->wire_count == 0, ("page %p is wired", m)); /* * Replace "m" with the new page. For * vm_page_replace(), "m" must be busy * and dequeued. Finally, change "m" * as if vm_page_free() was called. */ if (object->ref_count != 0) pmap_remove_all(m); m_new->aflags = m->aflags; KASSERT(m_new->oflags == VPO_UNMANAGED, ("page %p is managed", m)); m_new->oflags = m->oflags & VPO_NOSYNC; pmap_copy_page(m, m_new); m_new->valid = m->valid; m_new->dirty = m->dirty; m->flags &= ~PG_ZERO; vm_page_xbusy(m); vm_page_remque(m); vm_page_replace_checked(m_new, object, m->pindex, m); m->valid = 0; vm_page_undirty(m); /* * The new page must be deactivated * before the object is unlocked. */ vm_page_change_lock(m_new, &m_mtx); vm_page_deactivate(m_new); } else { m->flags &= ~PG_ZERO; vm_page_remque(m); vm_page_remove(m); KASSERT(m->dirty == 0, ("page %p is dirty", m)); } SLIST_INSERT_HEAD(&free, m, plinks.s.ss); } else error = EBUSY; unlock: VM_OBJECT_WUNLOCK(object); } else { MPASS(vm_phys_domain(m) == domain); vmd = VM_DOMAIN(domain); vm_domain_free_lock(vmd); order = m->order; if (order < VM_NFREEORDER) { /* * The page is enqueued in the physical memory * allocator's free page queues. Moreover, it * is the first page in a power-of-two-sized * run of contiguous free pages. Jump ahead * to the last page within that run, and * continue from there. */ m += (1 << order) - 1; } #if VM_NRESERVLEVEL > 0 else if (vm_reserv_is_page_free(m)) order = 0; #endif vm_domain_free_unlock(vmd); if (order == VM_NFREEORDER) error = EINVAL; } } if (m_mtx != NULL) mtx_unlock(m_mtx); if ((m = SLIST_FIRST(&free)) != NULL) { int cnt; vmd = VM_DOMAIN(domain); cnt = 0; vm_domain_free_lock(vmd); do { MPASS(vm_phys_domain(m) == domain); SLIST_REMOVE_HEAD(&free, plinks.s.ss); vm_page_free_phys(vmd, m); cnt++; } while ((m = SLIST_FIRST(&free)) != NULL); vm_domain_free_unlock(vmd); vm_domain_freecnt_inc(vmd, cnt); } return (error); } #define NRUNS 16 CTASSERT(powerof2(NRUNS)); #define RUN_INDEX(count) ((count) & (NRUNS - 1)) #define MIN_RECLAIM 8 /* * vm_page_reclaim_contig: * * Reclaim allocated, contiguous physical memory satisfying the specified * conditions by relocating the virtual pages using that physical memory. * Returns true if reclamation is successful and false otherwise. Since * relocation requires the allocation of physical pages, reclamation may * fail due to a shortage of free pages. When reclamation fails, callers * are expected to perform vm_wait() before retrying a failed allocation * operation, e.g., vm_page_alloc_contig(). * * The caller must always specify an allocation class through "req". * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * * The optional allocation flags are ignored. * * "npages" must be greater than zero. Both "alignment" and "boundary" * must be a power of two. */ bool vm_page_reclaim_contig_domain(int domain, int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary) { struct vm_domain *vmd; vm_paddr_t curr_low; vm_page_t m_run, m_runs[NRUNS]; u_long count, reclaimed; int error, i, options, req_class; KASSERT(npages > 0, ("npages is 0")); KASSERT(powerof2(alignment), ("alignment is not a power of 2")); KASSERT(powerof2(boundary), ("boundary is not a power of 2")); req_class = req & VM_ALLOC_CLASS_MASK; /* * The page daemon is allowed to dig deeper into the free page list. */ if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) req_class = VM_ALLOC_SYSTEM; /* * Return if the number of free pages cannot satisfy the requested * allocation. */ vmd = VM_DOMAIN(domain); count = vmd->vmd_free_count; if (count < npages + vmd->vmd_free_reserved || (count < npages + vmd->vmd_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) || (count < npages && req_class == VM_ALLOC_INTERRUPT)) return (false); /* * Scan up to three times, relaxing the restrictions ("options") on * the reclamation of reservations and superpages each time. */ for (options = VPSC_NORESERV;;) { /* * Find the highest runs that satisfy the given constraints * and restrictions, and record them in "m_runs". */ curr_low = low; count = 0; for (;;) { m_run = vm_phys_scan_contig(domain, npages, curr_low, high, alignment, boundary, options); if (m_run == NULL) break; curr_low = VM_PAGE_TO_PHYS(m_run) + ptoa(npages); m_runs[RUN_INDEX(count)] = m_run; count++; } /* * Reclaim the highest runs in LIFO (descending) order until * the number of reclaimed pages, "reclaimed", is at least * MIN_RECLAIM. Reset "reclaimed" each time because each * reclamation is idempotent, and runs will (likely) recur * from one scan to the next as restrictions are relaxed. */ reclaimed = 0; for (i = 0; count > 0 && i < NRUNS; i++) { count--; m_run = m_runs[RUN_INDEX(count)]; error = vm_page_reclaim_run(req_class, domain, npages, m_run, high); if (error == 0) { reclaimed += npages; if (reclaimed >= MIN_RECLAIM) return (true); } } /* * Either relax the restrictions on the next scan or return if * the last scan had no restrictions. */ if (options == VPSC_NORESERV) options = VPSC_NOSUPER; else if (options == VPSC_NOSUPER) options = VPSC_ANY; else if (options == VPSC_ANY) return (reclaimed != 0); } } bool vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary) { struct vm_domainset_iter di; int domain; bool ret; vm_domainset_iter_page_init(&di, kernel_object, &domain, &req); do { ret = vm_page_reclaim_contig_domain(domain, req, npages, low, high, alignment, boundary); if (ret) break; } while (vm_domainset_iter_page(&di, &domain, &req) == 0); return (ret); } /* * Set the domain in the appropriate page level domainset. */ void vm_domain_set(struct vm_domain *vmd) { mtx_lock(&vm_domainset_lock); if (!vmd->vmd_minset && vm_paging_min(vmd)) { vmd->vmd_minset = 1; DOMAINSET_SET(vmd->vmd_domain, &vm_min_domains); } if (!vmd->vmd_severeset && vm_paging_severe(vmd)) { vmd->vmd_severeset = 1; DOMAINSET_CLR(vmd->vmd_domain, &vm_severe_domains); } mtx_unlock(&vm_domainset_lock); } /* * Clear the domain from the appropriate page level domainset. */ void vm_domain_clear(struct vm_domain *vmd) { mtx_lock(&vm_domainset_lock); if (vmd->vmd_minset && !vm_paging_min(vmd)) { vmd->vmd_minset = 0; DOMAINSET_CLR(vmd->vmd_domain, &vm_min_domains); if (vm_min_waiters != 0) { vm_min_waiters = 0; wakeup(&vm_min_domains); } } if (vmd->vmd_severeset && !vm_paging_severe(vmd)) { vmd->vmd_severeset = 0; DOMAINSET_CLR(vmd->vmd_domain, &vm_severe_domains); if (vm_severe_waiters != 0) { vm_severe_waiters = 0; wakeup(&vm_severe_domains); } } /* * If pageout daemon needs pages, then tell it that there are * some free. */ if (vmd->vmd_pageout_pages_needed && vmd->vmd_free_count >= vmd->vmd_pageout_free_min) { wakeup(&vmd->vmd_pageout_pages_needed); vmd->vmd_pageout_pages_needed = 0; } /* See comments in vm_wait_doms(). */ if (vm_pageproc_waiters) { vm_pageproc_waiters = 0; wakeup(&vm_pageproc_waiters); } mtx_unlock(&vm_domainset_lock); } /* * Wait for free pages to exceed the min threshold globally. */ void vm_wait_min(void) { mtx_lock(&vm_domainset_lock); while (vm_page_count_min()) { vm_min_waiters++; msleep(&vm_min_domains, &vm_domainset_lock, PVM, "vmwait", 0); } mtx_unlock(&vm_domainset_lock); } /* * Wait for free pages to exceed the severe threshold globally. */ void vm_wait_severe(void) { mtx_lock(&vm_domainset_lock); while (vm_page_count_severe()) { vm_severe_waiters++; msleep(&vm_severe_domains, &vm_domainset_lock, PVM, "vmwait", 0); } mtx_unlock(&vm_domainset_lock); } u_int vm_wait_count(void) { return (vm_severe_waiters + vm_min_waiters + vm_pageproc_waiters); } static void vm_wait_doms(const domainset_t *wdoms) { /* * We use racey wakeup synchronization to avoid expensive global * locking for the pageproc when sleeping with a non-specific vm_wait. * To handle this, we only sleep for one tick in this instance. It * is expected that most allocations for the pageproc will come from * kmem or vm_page_grab* which will use the more specific and * race-free vm_wait_domain(). */ if (curproc == pageproc) { mtx_lock(&vm_domainset_lock); vm_pageproc_waiters++; msleep(&vm_pageproc_waiters, &vm_domainset_lock, PVM | PDROP, "pageprocwait", 1); } else { /* * XXX Ideally we would wait only until the allocation could * be satisfied. This condition can cause new allocators to * consume all freed pages while old allocators wait. */ mtx_lock(&vm_domainset_lock); if (DOMAINSET_SUBSET(&vm_min_domains, wdoms)) { vm_min_waiters++; msleep(&vm_min_domains, &vm_domainset_lock, PVM, "vmwait", 0); } mtx_unlock(&vm_domainset_lock); } } /* * vm_wait_domain: * * Sleep until free pages are available for allocation. * - Called in various places after failed memory allocations. */ void vm_wait_domain(int domain) { struct vm_domain *vmd; domainset_t wdom; vmd = VM_DOMAIN(domain); vm_domain_free_assert_unlocked(vmd); if (curproc == pageproc) { mtx_lock(&vm_domainset_lock); if (vmd->vmd_free_count < vmd->vmd_pageout_free_min) { vmd->vmd_pageout_pages_needed = 1; msleep(&vmd->vmd_pageout_pages_needed, &vm_domainset_lock, PDROP | PSWP, "VMWait", 0); } else mtx_unlock(&vm_domainset_lock); } else { if (pageproc == NULL) panic("vm_wait in early boot"); DOMAINSET_ZERO(&wdom); DOMAINSET_SET(vmd->vmd_domain, &wdom); vm_wait_doms(&wdom); } } /* * vm_wait: * * Sleep until free pages are available for allocation in the * affinity domains of the obj. If obj is NULL, the domain set * for the calling thread is used. * Called in various places after failed memory allocations. */ void vm_wait(vm_object_t obj) { struct domainset *d; d = NULL; /* * Carefully fetch pointers only once: the struct domainset * itself is ummutable but the pointer might change. */ if (obj != NULL) d = obj->domain.dr_policy; if (d == NULL) d = curthread->td_domain.dr_policy; vm_wait_doms(&d->ds_mask); } /* * vm_domain_alloc_fail: * * Called when a page allocation function fails. Informs the * pagedaemon and performs the requested wait. Requires the * domain_free and object lock on entry. Returns with the * object lock held and free lock released. Returns an error when * retry is necessary. * */ static int vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object, int req) { vm_domain_free_assert_unlocked(vmd); atomic_add_int(&vmd->vmd_pageout_deficit, max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); if (req & (VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL)) { if (object != NULL) VM_OBJECT_WUNLOCK(object); vm_wait_domain(vmd->vmd_domain); if (object != NULL) VM_OBJECT_WLOCK(object); if (req & VM_ALLOC_WAITOK) return (EAGAIN); } return (0); } /* * vm_waitpfault: * * Sleep until free pages are available for allocation. * - Called only in vm_fault so that processes page faulting * can be easily tracked. * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing * processes will be able to grab memory first. Do not change * this balance without careful testing first. */ void vm_waitpfault(void) { mtx_lock(&vm_domainset_lock); if (vm_page_count_min()) { vm_min_waiters++; msleep(&vm_min_domains, &vm_domainset_lock, PUSER, "pfault", 0); } mtx_unlock(&vm_domainset_lock); } struct vm_pagequeue * vm_page_pagequeue(vm_page_t m) { return (&vm_pagequeue_domain(m)->vmd_pagequeues[m->queue]); } /* * vm_page_dequeue: * * Remove the given page from its current page queue. * * The page must be locked. */ void vm_page_dequeue(vm_page_t m) { struct vm_pagequeue *pq; vm_page_assert_locked(m); KASSERT(m->queue < PQ_COUNT, ("vm_page_dequeue: page %p is not queued", m)); pq = vm_page_pagequeue(m); vm_pagequeue_lock(pq); m->queue = PQ_NONE; TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); vm_pagequeue_cnt_dec(pq); vm_pagequeue_unlock(pq); } /* * vm_page_dequeue_locked: * * Remove the given page from its current page queue. * * The page and page queue must be locked. */ void vm_page_dequeue_locked(vm_page_t m) { struct vm_pagequeue *pq; vm_page_lock_assert(m, MA_OWNED); pq = vm_page_pagequeue(m); vm_pagequeue_assert_locked(pq); m->queue = PQ_NONE; TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); vm_pagequeue_cnt_dec(pq); } /* * vm_page_enqueue: * * Add the given page to the specified page queue. * * The page must be locked. */ static void vm_page_enqueue(uint8_t queue, vm_page_t m) { struct vm_pagequeue *pq; vm_page_lock_assert(m, MA_OWNED); KASSERT(queue < PQ_COUNT, ("vm_page_enqueue: invalid queue %u request for page %p", queue, m)); pq = &vm_pagequeue_domain(m)->vmd_pagequeues[queue]; vm_pagequeue_lock(pq); m->queue = queue; TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); vm_pagequeue_cnt_inc(pq); vm_pagequeue_unlock(pq); } /* * vm_page_requeue: * * Move the given page to the tail of its current page queue. * * The page must be locked. */ void vm_page_requeue(vm_page_t m) { struct vm_pagequeue *pq; vm_page_lock_assert(m, MA_OWNED); KASSERT(m->queue != PQ_NONE, ("vm_page_requeue: page %p is not queued", m)); pq = vm_page_pagequeue(m); vm_pagequeue_lock(pq); TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); vm_pagequeue_unlock(pq); } /* * vm_page_requeue_locked: * * Move the given page to the tail of its current page queue. * * The page queue must be locked. */ void vm_page_requeue_locked(vm_page_t m) { struct vm_pagequeue *pq; KASSERT(m->queue != PQ_NONE, ("vm_page_requeue_locked: page %p is not queued", m)); pq = vm_page_pagequeue(m); vm_pagequeue_assert_locked(pq); TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); } /* * vm_page_activate: * * Put the specified page on the active list (if appropriate). * Ensure that act_count is at least ACT_INIT but do not otherwise * mess with it. * * The page must be locked. */ void vm_page_activate(vm_page_t m) { int queue; vm_page_lock_assert(m, MA_OWNED); if ((queue = m->queue) != PQ_ACTIVE) { if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { if (m->act_count < ACT_INIT) m->act_count = ACT_INIT; if (queue != PQ_NONE) vm_page_dequeue(m); vm_page_enqueue(PQ_ACTIVE, m); } } else { if (m->act_count < ACT_INIT) m->act_count = ACT_INIT; } } /* * vm_page_free_prep: * * Prepares the given page to be put on the free list, * disassociating it from any VM object. The caller may return * the page to the free list only if this function returns true. * * The object must be locked. The page must be locked if it is * managed. For a queued managed page, the pagequeue_locked * argument specifies whether the page queue is already locked. */ bool vm_page_free_prep(vm_page_t m, bool pagequeue_locked) { #if defined(DIAGNOSTIC) && defined(PHYS_TO_DMAP) if (PMAP_HAS_DMAP && (m->flags & PG_ZERO) != 0) { uint64_t *p; int i; p = (uint64_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)); for (i = 0; i < PAGE_SIZE / sizeof(uint64_t); i++, p++) KASSERT(*p == 0, ("vm_page_free_prep %p PG_ZERO %d %jx", m, i, (uintmax_t)*p)); } #endif if ((m->oflags & VPO_UNMANAGED) == 0) { vm_page_lock_assert(m, MA_OWNED); KASSERT(!pmap_page_is_mapped(m), ("vm_page_free_toq: freeing mapped page %p", m)); } else KASSERT(m->queue == PQ_NONE, ("vm_page_free_toq: unmanaged page %p is queued", m)); VM_CNT_INC(v_tfree); if (vm_page_sbusied(m)) panic("vm_page_free: freeing busy page %p", m); vm_page_remove(m); /* * If fictitious remove object association and * return. */ if ((m->flags & PG_FICTITIOUS) != 0) { KASSERT(m->wire_count == 1, ("fictitious page %p is not wired", m)); KASSERT(m->queue == PQ_NONE, ("fictitious page %p is queued", m)); return (false); } if (m->queue != PQ_NONE) { if (pagequeue_locked) vm_page_dequeue_locked(m); else vm_page_dequeue(m); } m->valid = 0; vm_page_undirty(m); if (m->wire_count != 0) panic("vm_page_free: freeing wired page %p", m); if (m->hold_count != 0) { m->flags &= ~PG_ZERO; KASSERT((m->flags & PG_UNHOLDFREE) == 0, ("vm_page_free: freeing PG_UNHOLDFREE page %p", m)); m->flags |= PG_UNHOLDFREE; return (false); } /* * Restore the default memory attribute to the page. */ if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); return (true); } /* * Insert the page into the physical memory allocator's free page * queues. This is the last step to free a page. The caller is * responsible for adjusting the free page count. */ static void vm_page_free_phys(struct vm_domain *vmd, vm_page_t m) { vm_domain_free_assert_locked(vmd); #if VM_NRESERVLEVEL > 0 if (!vm_reserv_free_page(m)) #endif vm_phys_free_pages(m, 0); } void vm_page_free_phys_pglist(struct pglist *tq) { struct vm_domain *vmd; vm_page_t m; int cnt; if (TAILQ_EMPTY(tq)) return; vmd = NULL; cnt = 0; TAILQ_FOREACH(m, tq, listq) { if (vmd != vm_pagequeue_domain(m)) { if (vmd != NULL) { vm_domain_free_unlock(vmd); vm_domain_freecnt_inc(vmd, cnt); cnt = 0; } vmd = vm_pagequeue_domain(m); vm_domain_free_lock(vmd); } vm_page_free_phys(vmd, m); cnt++; } if (vmd != NULL) { vm_domain_free_unlock(vmd); vm_domain_freecnt_inc(vmd, cnt); } } /* * vm_page_free_toq: * * Returns the given page to the free list, disassociating it * from any VM object. * * The object must be locked. The page must be locked if it is * managed. */ void vm_page_free_toq(vm_page_t m) { struct vm_domain *vmd; if (!vm_page_free_prep(m, false)) return; vmd = vm_pagequeue_domain(m); vm_domain_free_lock(vmd); vm_page_free_phys(vmd, m); vm_domain_free_unlock(vmd); vm_domain_freecnt_inc(vmd, 1); } /* * vm_page_free_pages_toq: * * Returns a list of pages to the free list, disassociating it * from any VM object. In other words, this is equivalent to * calling vm_page_free_toq() for each page of a list of VM objects. * * The objects must be locked. The pages must be locked if it is * managed. */ void vm_page_free_pages_toq(struct spglist *free, bool update_wire_count) { vm_page_t m; struct pglist pgl; int count; if (SLIST_EMPTY(free)) return; count = 0; TAILQ_INIT(&pgl); while ((m = SLIST_FIRST(free)) != NULL) { count++; SLIST_REMOVE_HEAD(free, plinks.s.ss); if (vm_page_free_prep(m, false)) TAILQ_INSERT_TAIL(&pgl, m, listq); } vm_page_free_phys_pglist(&pgl); if (update_wire_count) vm_wire_sub(count); } /* * vm_page_wire: * * Mark this page as wired down. If the page is fictitious, then * its wire count must remain one. * * The page must be locked. */ void vm_page_wire(vm_page_t m) { vm_page_assert_locked(m); if ((m->flags & PG_FICTITIOUS) != 0) { KASSERT(m->wire_count == 1, ("vm_page_wire: fictitious page %p's wire count isn't one", m)); return; } if (m->wire_count == 0) { KASSERT((m->oflags & VPO_UNMANAGED) == 0 || m->queue == PQ_NONE, ("vm_page_wire: unmanaged page %p is queued", m)); vm_wire_add(1); } m->wire_count++; KASSERT(m->wire_count != 0, ("vm_page_wire: wire_count overflow m=%p", m)); } /* * vm_page_unwire: * * Release one wiring of the specified page, potentially allowing it to be * paged out. Returns TRUE if the number of wirings transitions to zero and * FALSE otherwise. * * Only managed pages belonging to an object can be paged out. If the number * of wirings transitions to zero and the page is eligible for page out, then * the page is added to the specified paging queue (unless PQ_NONE is * specified, in which case the page is dequeued if it belongs to a paging * queue). * * If a page is fictitious, then its wire count must always be one. * * A managed page must be locked. */ bool vm_page_unwire(vm_page_t m, uint8_t queue) { bool unwired; KASSERT(queue < PQ_COUNT || queue == PQ_NONE, ("vm_page_unwire: invalid queue %u request for page %p", queue, m)); unwired = vm_page_unwire_noq(m); if (unwired && (m->oflags & VPO_UNMANAGED) == 0 && m->object != NULL) { if (m->queue == queue) { if (queue == PQ_ACTIVE) vm_page_reference(m); else if (queue != PQ_NONE) vm_page_requeue(m); } else { vm_page_remque(m); if (queue != PQ_NONE) { vm_page_enqueue(queue, m); if (queue == PQ_ACTIVE) /* Initialize act_count. */ vm_page_activate(m); } } } return (unwired); } /* * * vm_page_unwire_noq: * * Unwire a page without (re-)inserting it into a page queue. It is up * to the caller to enqueue, requeue, or free the page as appropriate. * In most cases, vm_page_unwire() should be used instead. */ bool vm_page_unwire_noq(vm_page_t m) { if ((m->oflags & VPO_UNMANAGED) == 0) vm_page_assert_locked(m); if ((m->flags & PG_FICTITIOUS) != 0) { KASSERT(m->wire_count == 1, ("vm_page_unwire: fictitious page %p's wire count isn't one", m)); return (false); } if (m->wire_count == 0) panic("vm_page_unwire: page %p's wire count is zero", m); m->wire_count--; if (m->wire_count == 0) { vm_wire_sub(1); return (true); } else return (false); } /* * Move the specified page to the inactive queue, or requeue the page if it is * already in the inactive queue. * * Normally, "noreuse" is FALSE, resulting in LRU ordering of the inactive * queue. However, setting "noreuse" to TRUE will accelerate the specified * page's reclamation, but it will not unmap the page from any address space. * This is implemented by inserting the page near the head of the inactive * queue, using a marker page to guide FIFO insertion ordering. * * The page must be locked. */ static inline void _vm_page_deactivate(vm_page_t m, boolean_t noreuse) { struct vm_pagequeue *pq; int queue; vm_page_assert_locked(m); if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { pq = &vm_pagequeue_domain(m)->vmd_pagequeues[PQ_INACTIVE]; /* Avoid multiple acquisitions of the inactive queue lock. */ queue = m->queue; if (queue == PQ_INACTIVE) { vm_pagequeue_lock(pq); vm_page_dequeue_locked(m); } else { if (queue != PQ_NONE) vm_page_dequeue(m); vm_pagequeue_lock(pq); } m->queue = PQ_INACTIVE; if (noreuse) TAILQ_INSERT_BEFORE( &vm_pagequeue_domain(m)->vmd_inacthead, m, plinks.q); else TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); vm_pagequeue_cnt_inc(pq); vm_pagequeue_unlock(pq); } } /* * Move the specified page to the inactive queue, or requeue the page if it is * already in the inactive queue. * * The page must be locked. */ void vm_page_deactivate(vm_page_t m) { _vm_page_deactivate(m, FALSE); } /* * Move the specified page to the inactive queue with the expectation * that it is unlikely to be reused. * * The page must be locked. */ void vm_page_deactivate_noreuse(vm_page_t m) { _vm_page_deactivate(m, TRUE); } /* * vm_page_launder * * Put a page in the laundry, or requeue it if it is already there. */ void vm_page_launder(vm_page_t m) { vm_page_assert_locked(m); if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { if (m->queue == PQ_LAUNDRY) vm_page_requeue(m); else { vm_page_remque(m); vm_page_enqueue(PQ_LAUNDRY, m); } } } /* * vm_page_unswappable * * Put a page in the PQ_UNSWAPPABLE holding queue. */ void vm_page_unswappable(vm_page_t m) { vm_page_assert_locked(m); KASSERT(m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0, ("page %p already unswappable", m)); if (m->queue != PQ_NONE) vm_page_dequeue(m); vm_page_enqueue(PQ_UNSWAPPABLE, m); } /* * Attempt to free the page. If it cannot be freed, do nothing. Returns true * if the page is freed and false otherwise. * * The page must be managed. The page and its containing object must be * locked. */ bool vm_page_try_to_free(vm_page_t m) { vm_page_assert_locked(m); VM_OBJECT_ASSERT_WLOCKED(m->object); KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("page %p is unmanaged", m)); if (m->dirty != 0 || vm_page_held(m) || vm_page_busied(m)) return (false); if (m->object->ref_count != 0) { pmap_remove_all(m); if (m->dirty != 0) return (false); } vm_page_free(m); return (true); } /* * vm_page_advise * * Apply the specified advice to the given page. * * The object and page must be locked. */ void vm_page_advise(vm_page_t m, int advice) { vm_page_assert_locked(m); VM_OBJECT_ASSERT_WLOCKED(m->object); if (advice == MADV_FREE) /* * Mark the page clean. This will allow the page to be freed * without first paging it out. MADV_FREE pages are often * quickly reused by malloc(3), so we do not do anything that * would result in a page fault on a later access. */ vm_page_undirty(m); else if (advice != MADV_DONTNEED) { if (advice == MADV_WILLNEED) vm_page_activate(m); return; } /* * Clear any references to the page. Otherwise, the page daemon will * immediately reactivate the page. */ vm_page_aflag_clear(m, PGA_REFERENCED); if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m)) vm_page_dirty(m); /* * Place clean pages near the head of the inactive queue rather than * the tail, thus defeating the queue's LRU operation and ensuring that * the page will be reused quickly. Dirty pages not already in the * laundry are moved there. */ if (m->dirty == 0) vm_page_deactivate_noreuse(m); else if (!vm_page_in_laundry(m)) vm_page_launder(m); } /* * Grab a page, waiting until we are waken up due to the page * changing state. We keep on waiting, if the page continues * to be in the object. If the page doesn't exist, first allocate it * and then conditionally zero it. * * This routine may sleep. * * The object must be locked on entry. The lock will, however, be released * and reacquired if the routine sleeps. */ vm_page_t vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) { vm_page_t m; int sleep; int pflags; VM_OBJECT_ASSERT_WLOCKED(object); KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || (allocflags & VM_ALLOC_IGN_SBUSY) != 0, ("vm_page_grab: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); pflags = allocflags & ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL); if ((allocflags & VM_ALLOC_NOWAIT) == 0) pflags |= VM_ALLOC_WAITFAIL; retrylookup: if ((m = vm_page_lookup(object, pindex)) != NULL) { sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ? vm_page_xbusied(m) : vm_page_busied(m); if (sleep) { if ((allocflags & VM_ALLOC_NOWAIT) != 0) return (NULL); /* * Reference the page before unlocking and * sleeping so that the page daemon is less * likely to reclaim it. */ vm_page_aflag_set(m, PGA_REFERENCED); vm_page_lock(m); VM_OBJECT_WUNLOCK(object); vm_page_busy_sleep(m, "pgrbwt", (allocflags & VM_ALLOC_IGN_SBUSY) != 0); VM_OBJECT_WLOCK(object); goto retrylookup; } else { if ((allocflags & VM_ALLOC_WIRED) != 0) { vm_page_lock(m); vm_page_wire(m); vm_page_unlock(m); } if ((allocflags & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) vm_page_xbusy(m); if ((allocflags & VM_ALLOC_SBUSY) != 0) vm_page_sbusy(m); return (m); } } m = vm_page_alloc(object, pindex, pflags); if (m == NULL) { if ((allocflags & VM_ALLOC_NOWAIT) != 0) return (NULL); goto retrylookup; } if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0) pmap_zero_page(m); return (m); } /* * Return the specified range of pages from the given object. For each * page offset within the range, if a page already exists within the object * at that offset and it is busy, then wait for it to change state. If, * instead, the page doesn't exist, then allocate it. * * The caller must always specify an allocation class. * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs the pages * * The caller must always specify that the pages are to be busied and/or * wired. * * optional allocation flags: * VM_ALLOC_IGN_SBUSY do not sleep on soft busy pages * VM_ALLOC_NOBUSY do not exclusive busy the page * VM_ALLOC_NOWAIT do not sleep * VM_ALLOC_SBUSY set page to sbusy state * VM_ALLOC_WIRED wire the pages * VM_ALLOC_ZERO zero and validate any invalid pages * * If VM_ALLOC_NOWAIT is not specified, this routine may sleep. Otherwise, it * may return a partial prefix of the requested range. */ int vm_page_grab_pages(vm_object_t object, vm_pindex_t pindex, int allocflags, vm_page_t *ma, int count) { vm_page_t m, mpred; int pflags; int i; bool sleep; VM_OBJECT_ASSERT_WLOCKED(object); KASSERT(((u_int)allocflags >> VM_ALLOC_COUNT_SHIFT) == 0, ("vm_page_grap_pages: VM_ALLOC_COUNT() is not allowed")); KASSERT((allocflags & VM_ALLOC_NOBUSY) == 0 || (allocflags & VM_ALLOC_WIRED) != 0, ("vm_page_grab_pages: the pages must be busied or wired")); KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || (allocflags & VM_ALLOC_IGN_SBUSY) != 0, ("vm_page_grab_pages: VM_ALLOC_SBUSY/IGN_SBUSY mismatch")); if (count == 0) return (0); pflags = allocflags & ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL | VM_ALLOC_IGN_SBUSY); if ((allocflags & VM_ALLOC_NOWAIT) == 0) pflags |= VM_ALLOC_WAITFAIL; i = 0; retrylookup: m = vm_radix_lookup_le(&object->rtree, pindex + i); if (m == NULL || m->pindex != pindex + i) { mpred = m; m = NULL; } else mpred = TAILQ_PREV(m, pglist, listq); for (; i < count; i++) { if (m != NULL) { sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ? vm_page_xbusied(m) : vm_page_busied(m); if (sleep) { if ((allocflags & VM_ALLOC_NOWAIT) != 0) break; /* * Reference the page before unlocking and * sleeping so that the page daemon is less * likely to reclaim it. */ vm_page_aflag_set(m, PGA_REFERENCED); vm_page_lock(m); VM_OBJECT_WUNLOCK(object); vm_page_busy_sleep(m, "grbmaw", (allocflags & VM_ALLOC_IGN_SBUSY) != 0); VM_OBJECT_WLOCK(object); goto retrylookup; } if ((allocflags & VM_ALLOC_WIRED) != 0) { vm_page_lock(m); vm_page_wire(m); vm_page_unlock(m); } if ((allocflags & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) vm_page_xbusy(m); if ((allocflags & VM_ALLOC_SBUSY) != 0) vm_page_sbusy(m); } else { m = vm_page_alloc_after(object, pindex + i, pflags | VM_ALLOC_COUNT(count - i), mpred); if (m == NULL) { if ((allocflags & VM_ALLOC_NOWAIT) != 0) break; goto retrylookup; } } if (m->valid == 0 && (allocflags & VM_ALLOC_ZERO) != 0) { if ((m->flags & PG_ZERO) == 0) pmap_zero_page(m); m->valid = VM_PAGE_BITS_ALL; } ma[i] = mpred = m; m = vm_page_next(m); } return (i); } /* * Mapping function for valid or dirty bits in a page. * * Inputs are required to range within a page. */ vm_page_bits_t vm_page_bits(int base, int size) { int first_bit; int last_bit; KASSERT( base + size <= PAGE_SIZE, ("vm_page_bits: illegal base/size %d/%d", base, size) ); if (size == 0) /* handle degenerate case */ return (0); first_bit = base >> DEV_BSHIFT; last_bit = (base + size - 1) >> DEV_BSHIFT; return (((vm_page_bits_t)2 << last_bit) - ((vm_page_bits_t)1 << first_bit)); } /* * vm_page_set_valid_range: * * Sets portions of a page valid. The arguments are expected * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive * of any partial chunks touched by the range. The invalid portion of * such chunks will be zeroed. * * (base + size) must be less then or equal to PAGE_SIZE. */ void vm_page_set_valid_range(vm_page_t m, int base, int size) { int endoff, frag; VM_OBJECT_ASSERT_WLOCKED(m->object); if (size == 0) /* handle degenerate case */ return; /* * If the base is not DEV_BSIZE aligned and the valid * bit is clear, we have to zero out a portion of the * first block. */ if ((frag = rounddown2(base, DEV_BSIZE)) != base && (m->valid & (1 << (base >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, frag, base - frag); /* * If the ending offset is not DEV_BSIZE aligned and the * valid bit is clear, we have to zero out a portion of * the last block. */ endoff = base + size; if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, endoff, DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); /* * Assert that no previously invalid block that is now being validated * is already dirty. */ KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0, ("vm_page_set_valid_range: page %p is dirty", m)); /* * Set valid bits inclusive of any overlap. */ m->valid |= vm_page_bits(base, size); } /* * Clear the given bits from the specified page's dirty field. */ static __inline void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits) { uintptr_t addr; #if PAGE_SIZE < 16384 int shift; #endif /* * If the object is locked and the page is neither exclusive busy nor * write mapped, then the page's dirty field cannot possibly be * set by a concurrent pmap operation. */ VM_OBJECT_ASSERT_WLOCKED(m->object); if (!vm_page_xbusied(m) && !pmap_page_is_write_mapped(m)) m->dirty &= ~pagebits; else { /* * The pmap layer can call vm_page_dirty() without * holding a distinguished lock. The combination of * the object's lock and an atomic operation suffice * to guarantee consistency of the page dirty field. * * For PAGE_SIZE == 32768 case, compiler already * properly aligns the dirty field, so no forcible * alignment is needed. Only require existence of * atomic_clear_64 when page size is 32768. */ addr = (uintptr_t)&m->dirty; #if PAGE_SIZE == 32768 atomic_clear_64((uint64_t *)addr, pagebits); #elif PAGE_SIZE == 16384 atomic_clear_32((uint32_t *)addr, pagebits); #else /* PAGE_SIZE <= 8192 */ /* * Use a trick to perform a 32-bit atomic on the * containing aligned word, to not depend on the existence * of atomic_clear_{8, 16}. */ shift = addr & (sizeof(uint32_t) - 1); #if BYTE_ORDER == BIG_ENDIAN shift = (sizeof(uint32_t) - sizeof(m->dirty) - shift) * NBBY; #else shift *= NBBY; #endif addr &= ~(sizeof(uint32_t) - 1); atomic_clear_32((uint32_t *)addr, pagebits << shift); #endif /* PAGE_SIZE */ } } /* * vm_page_set_validclean: * * Sets portions of a page valid and clean. The arguments are expected * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive * of any partial chunks touched by the range. The invalid portion of * such chunks will be zero'd. * * (base + size) must be less then or equal to PAGE_SIZE. */ void vm_page_set_validclean(vm_page_t m, int base, int size) { vm_page_bits_t oldvalid, pagebits; int endoff, frag; VM_OBJECT_ASSERT_WLOCKED(m->object); if (size == 0) /* handle degenerate case */ return; /* * If the base is not DEV_BSIZE aligned and the valid * bit is clear, we have to zero out a portion of the * first block. */ if ((frag = rounddown2(base, DEV_BSIZE)) != base && (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, frag, base - frag); /* * If the ending offset is not DEV_BSIZE aligned and the * valid bit is clear, we have to zero out a portion of * the last block. */ endoff = base + size; if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, endoff, DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); /* * Set valid, clear dirty bits. If validating the entire * page we can safely clear the pmap modify bit. We also * use this opportunity to clear the VPO_NOSYNC flag. If a process * takes a write fault on a MAP_NOSYNC memory area the flag will * be set again. * * We set valid bits inclusive of any overlap, but we can only * clear dirty bits for DEV_BSIZE chunks that are fully within * the range. */ oldvalid = m->valid; pagebits = vm_page_bits(base, size); m->valid |= pagebits; #if 0 /* NOT YET */ if ((frag = base & (DEV_BSIZE - 1)) != 0) { frag = DEV_BSIZE - frag; base += frag; size -= frag; if (size < 0) size = 0; } pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1)); #endif if (base == 0 && size == PAGE_SIZE) { /* * The page can only be modified within the pmap if it is * mapped, and it can only be mapped if it was previously * fully valid. */ if (oldvalid == VM_PAGE_BITS_ALL) /* * Perform the pmap_clear_modify() first. Otherwise, * a concurrent pmap operation, such as * pmap_protect(), could clear a modification in the * pmap and set the dirty field on the page before * pmap_clear_modify() had begun and after the dirty * field was cleared here. */ pmap_clear_modify(m); m->dirty = 0; m->oflags &= ~VPO_NOSYNC; } else if (oldvalid != VM_PAGE_BITS_ALL) m->dirty &= ~pagebits; else vm_page_clear_dirty_mask(m, pagebits); } void vm_page_clear_dirty(vm_page_t m, int base, int size) { vm_page_clear_dirty_mask(m, vm_page_bits(base, size)); } /* * vm_page_set_invalid: * * Invalidates DEV_BSIZE'd chunks within a page. Both the * valid and dirty bits for the effected areas are cleared. */ void vm_page_set_invalid(vm_page_t m, int base, int size) { vm_page_bits_t bits; vm_object_t object; object = m->object; VM_OBJECT_ASSERT_WLOCKED(object); if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) + size >= object->un_pager.vnp.vnp_size) bits = VM_PAGE_BITS_ALL; else bits = vm_page_bits(base, size); if (object->ref_count != 0 && m->valid == VM_PAGE_BITS_ALL && bits != 0) pmap_remove_all(m); KASSERT((bits == 0 && m->valid == VM_PAGE_BITS_ALL) || !pmap_page_is_mapped(m), ("vm_page_set_invalid: page %p is mapped", m)); m->valid &= ~bits; m->dirty &= ~bits; } /* * vm_page_zero_invalid() * * The kernel assumes that the invalid portions of a page contain * garbage, but such pages can be mapped into memory by user code. * When this occurs, we must zero out the non-valid portions of the * page so user code sees what it expects. * * Pages are most often semi-valid when the end of a file is mapped * into memory and the file's size is not page aligned. */ void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid) { int b; int i; VM_OBJECT_ASSERT_WLOCKED(m->object); /* * Scan the valid bits looking for invalid sections that * must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the * valid bit may be set ) have already been zeroed by * vm_page_set_validclean(). */ for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) { if (i == (PAGE_SIZE / DEV_BSIZE) || (m->valid & ((vm_page_bits_t)1 << i))) { if (i > b) { pmap_zero_page_area(m, b << DEV_BSHIFT, (i - b) << DEV_BSHIFT); } b = i + 1; } } /* * setvalid is TRUE when we can safely set the zero'd areas * as being valid. We can do this if there are no cache consistancy * issues. e.g. it is ok to do with UFS, but not ok to do with NFS. */ if (setvalid) m->valid = VM_PAGE_BITS_ALL; } /* * vm_page_is_valid: * * Is (partial) page valid? Note that the case where size == 0 * will return FALSE in the degenerate case where the page is * entirely invalid, and TRUE otherwise. */ int vm_page_is_valid(vm_page_t m, int base, int size) { vm_page_bits_t bits; VM_OBJECT_ASSERT_LOCKED(m->object); bits = vm_page_bits(base, size); return (m->valid != 0 && (m->valid & bits) == bits); } /* * Returns true if all of the specified predicates are true for the entire * (super)page and false otherwise. */ bool vm_page_ps_test(vm_page_t m, int flags, vm_page_t skip_m) { vm_object_t object; int i, npages; object = m->object; VM_OBJECT_ASSERT_LOCKED(object); npages = atop(pagesizes[m->psind]); /* * The physically contiguous pages that make up a superpage, i.e., a * page with a page size index ("psind") greater than zero, will * occupy adjacent entries in vm_page_array[]. */ for (i = 0; i < npages; i++) { /* Always test object consistency, including "skip_m". */ if (m[i].object != object) return (false); if (&m[i] == skip_m) continue; if ((flags & PS_NONE_BUSY) != 0 && vm_page_busied(&m[i])) return (false); if ((flags & PS_ALL_DIRTY) != 0) { /* * Calling vm_page_test_dirty() or pmap_is_modified() * might stop this case from spuriously returning * "false". However, that would require a write lock * on the object containing "m[i]". */ if (m[i].dirty != VM_PAGE_BITS_ALL) return (false); } if ((flags & PS_ALL_VALID) != 0 && m[i].valid != VM_PAGE_BITS_ALL) return (false); } return (true); } /* * Set the page's dirty bits if the page is modified. */ void vm_page_test_dirty(vm_page_t m) { VM_OBJECT_ASSERT_WLOCKED(m->object); if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m)) vm_page_dirty(m); } void vm_page_lock_KBI(vm_page_t m, const char *file, int line) { mtx_lock_flags_(vm_page_lockptr(m), 0, file, line); } void vm_page_unlock_KBI(vm_page_t m, const char *file, int line) { mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line); } int vm_page_trylock_KBI(vm_page_t m, const char *file, int line) { return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line)); } #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) void vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line) { vm_page_lock_assert_KBI(m, MA_OWNED, file, line); } void vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line) { mtx_assert_(vm_page_lockptr(m), a, file, line); } #endif #ifdef INVARIANTS void vm_page_object_lock_assert(vm_page_t m) { /* * Certain of the page's fields may only be modified by the * holder of the containing object's lock or the exclusive busy. * holder. Unfortunately, the holder of the write busy is * not recorded, and thus cannot be checked here. */ if (m->object != NULL && !vm_page_xbusied(m)) VM_OBJECT_ASSERT_WLOCKED(m->object); } void vm_page_assert_pga_writeable(vm_page_t m, uint8_t bits) { if ((bits & PGA_WRITEABLE) == 0) return; /* * The PGA_WRITEABLE flag can only be set if the page is * managed, is exclusively busied or the object is locked. * Currently, this flag is only set by pmap_enter(). */ KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("PGA_WRITEABLE on unmanaged page")); if (!vm_page_xbusied(m)) VM_OBJECT_ASSERT_LOCKED(m->object); } #endif #include "opt_ddb.h" #ifdef DDB #include #include DB_SHOW_COMMAND(page, vm_page_print_page_info) { db_printf("vm_cnt.v_free_count: %d\n", vm_free_count()); db_printf("vm_cnt.v_inactive_count: %d\n", vm_inactive_count()); db_printf("vm_cnt.v_active_count: %d\n", vm_active_count()); db_printf("vm_cnt.v_laundry_count: %d\n", vm_laundry_count()); db_printf("vm_cnt.v_wire_count: %d\n", vm_wire_count()); db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved); db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min); db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target); db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target); } DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info) { int dom; db_printf("pq_free %d\n", vm_free_count()); for (dom = 0; dom < vm_ndomains; dom++) { db_printf( "dom %d page_cnt %d free %d pq_act %d pq_inact %d pq_laund %d pq_unsw %d\n", dom, vm_dom[dom].vmd_page_count, vm_dom[dom].vmd_free_count, vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt, vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt, vm_dom[dom].vmd_pagequeues[PQ_LAUNDRY].pq_cnt, vm_dom[dom].vmd_pagequeues[PQ_UNSWAPPABLE].pq_cnt); } } DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo) { vm_page_t m; boolean_t phys; if (!have_addr) { db_printf("show pginfo addr\n"); return; } phys = strchr(modif, 'p') != NULL; if (phys) m = PHYS_TO_VM_PAGE(addr); else m = (vm_page_t)addr; db_printf( "page %p obj %p pidx 0x%jx phys 0x%jx q %d hold %d wire %d\n" " af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n", m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr, m->queue, m->hold_count, m->wire_count, m->aflags, m->oflags, m->flags, m->act_count, m->busy_lock, m->valid, m->dirty); } #endif /* DDB */