/* $NetBSD: subr_pool.c,v 1.76 2002/03/13 10:57:18 simonb Exp $ */ /*- * Copyright (c) 1997, 1999, 2000 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Paul Kranenburg; by Jason R. Thorpe of the Numerical Aerospace * Simulation Facility, NASA Ames Research Center. * * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the NetBSD * Foundation, Inc. and its contributors. * 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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. */ #include __KERNEL_RCSID(0, "$NetBSD: subr_pool.c,v 1.76 2002/03/13 10:57:18 simonb Exp $"); #include "opt_pool.h" #include "opt_poollog.h" #include "opt_lockdebug.h" #include #include #include #include #include #include #include #include #include #include /* * Pool resource management utility. * * Memory is allocated in pages which are split into pieces according * to the pool item size. Each page is kept on a list headed by `pr_pagelist' * in the pool structure and the individual pool items are on a linked list * headed by `ph_itemlist' in each page header. The memory for building * the page list is either taken from the allocated pages themselves (for * small pool items) or taken from an internal pool of page headers (`phpool'). */ /* List of all pools */ TAILQ_HEAD(,pool) pool_head = TAILQ_HEAD_INITIALIZER(pool_head); /* Private pool for page header structures */ static struct pool phpool; #ifdef POOL_SUBPAGE /* Pool of subpages for use by normal pools. */ static struct pool psppool; #endif /* # of seconds to retain page after last use */ int pool_inactive_time = 10; /* Next candidate for drainage (see pool_drain()) */ static struct pool *drainpp; /* This spin lock protects both pool_head and drainpp. */ struct simplelock pool_head_slock = SIMPLELOCK_INITIALIZER; struct pool_item_header { /* Page headers */ TAILQ_ENTRY(pool_item_header) ph_pagelist; /* pool page list */ TAILQ_HEAD(,pool_item) ph_itemlist; /* chunk list for this page */ LIST_ENTRY(pool_item_header) ph_hashlist; /* Off-page page headers */ int ph_nmissing; /* # of chunks in use */ caddr_t ph_page; /* this page's address */ struct timeval ph_time; /* last referenced */ }; TAILQ_HEAD(pool_pagelist,pool_item_header); struct pool_item { #ifdef DIAGNOSTIC int pi_magic; #endif #define PI_MAGIC 0xdeadbeef /* Other entries use only this list entry */ TAILQ_ENTRY(pool_item) pi_list; }; #define PR_HASH_INDEX(pp,addr) \ (((u_long)(addr) >> (pp)->pr_alloc->pa_pageshift) & \ (PR_HASHTABSIZE - 1)) #define POOL_NEEDS_CATCHUP(pp) \ ((pp)->pr_nitems < (pp)->pr_minitems) /* * Pool cache management. * * Pool caches provide a way for constructed objects to be cached by the * pool subsystem. This can lead to performance improvements by avoiding * needless object construction/destruction; it is deferred until absolutely * necessary. * * Caches are grouped into cache groups. Each cache group references * up to 16 constructed objects. When a cache allocates an object * from the pool, it calls the object's constructor and places it into * a cache group. When a cache group frees an object back to the pool, * it first calls the object's destructor. This allows the object to * persist in constructed form while freed to the cache. * * Multiple caches may exist for each pool. This allows a single * object type to have multiple constructed forms. The pool references * each cache, so that when a pool is drained by the pagedaemon, it can * drain each individual cache as well. Each time a cache is drained, * the most idle cache group is freed to the pool in its entirety. * * Pool caches are layed on top of pools. By layering them, we can avoid * the complexity of cache management for pools which would not benefit * from it. */ /* The cache group pool. */ static struct pool pcgpool; static void pool_cache_reclaim(struct pool_cache *); static int pool_catchup(struct pool *); static void pool_prime_page(struct pool *, caddr_t, struct pool_item_header *); void *pool_allocator_alloc(struct pool *, int); void pool_allocator_free(struct pool *, void *); static void pool_print1(struct pool *, const char *, void (*)(const char *, ...)); /* * Pool log entry. An array of these is allocated in pool_init(). */ struct pool_log { const char *pl_file; long pl_line; int pl_action; #define PRLOG_GET 1 #define PRLOG_PUT 2 void *pl_addr; }; /* Number of entries in pool log buffers */ #ifndef POOL_LOGSIZE #define POOL_LOGSIZE 10 #endif int pool_logsize = POOL_LOGSIZE; #ifdef POOL_DIAGNOSTIC static __inline void pr_log(struct pool *pp, void *v, int action, const char *file, long line) { int n = pp->pr_curlogentry; struct pool_log *pl; if ((pp->pr_roflags & PR_LOGGING) == 0) return; /* * Fill in the current entry. Wrap around and overwrite * the oldest entry if necessary. */ pl = &pp->pr_log[n]; pl->pl_file = file; pl->pl_line = line; pl->pl_action = action; pl->pl_addr = v; if (++n >= pp->pr_logsize) n = 0; pp->pr_curlogentry = n; } static void pr_printlog(struct pool *pp, struct pool_item *pi, void (*pr)(const char *, ...)) { int i = pp->pr_logsize; int n = pp->pr_curlogentry; if ((pp->pr_roflags & PR_LOGGING) == 0) return; /* * Print all entries in this pool's log. */ while (i-- > 0) { struct pool_log *pl = &pp->pr_log[n]; if (pl->pl_action != 0) { if (pi == NULL || pi == pl->pl_addr) { (*pr)("\tlog entry %d:\n", i); (*pr)("\t\taction = %s, addr = %p\n", pl->pl_action == PRLOG_GET ? "get" : "put", pl->pl_addr); (*pr)("\t\tfile: %s at line %lu\n", pl->pl_file, pl->pl_line); } } if (++n >= pp->pr_logsize) n = 0; } } static __inline void pr_enter(struct pool *pp, const char *file, long line) { if (__predict_false(pp->pr_entered_file != NULL)) { printf("pool %s: reentrancy at file %s line %ld\n", pp->pr_wchan, file, line); printf(" previous entry at file %s line %ld\n", pp->pr_entered_file, pp->pr_entered_line); panic("pr_enter"); } pp->pr_entered_file = file; pp->pr_entered_line = line; } static __inline void pr_leave(struct pool *pp) { if (__predict_false(pp->pr_entered_file == NULL)) { printf("pool %s not entered?\n", pp->pr_wchan); panic("pr_leave"); } pp->pr_entered_file = NULL; pp->pr_entered_line = 0; } static __inline void pr_enter_check(struct pool *pp, void (*pr)(const char *, ...)) { if (pp->pr_entered_file != NULL) (*pr)("\n\tcurrently entered from file %s line %ld\n", pp->pr_entered_file, pp->pr_entered_line); } #else #define pr_log(pp, v, action, file, line) #define pr_printlog(pp, pi, pr) #define pr_enter(pp, file, line) #define pr_leave(pp) #define pr_enter_check(pp, pr) #endif /* POOL_DIAGNOSTIC */ /* * Return the pool page header based on page address. */ static __inline struct pool_item_header * pr_find_pagehead(struct pool *pp, caddr_t page) { struct pool_item_header *ph; if ((pp->pr_roflags & PR_PHINPAGE) != 0) return ((struct pool_item_header *)(page + pp->pr_phoffset)); for (ph = LIST_FIRST(&pp->pr_hashtab[PR_HASH_INDEX(pp, page)]); ph != NULL; ph = LIST_NEXT(ph, ph_hashlist)) { if (ph->ph_page == page) return (ph); } return (NULL); } /* * Remove a page from the pool. */ static __inline void pr_rmpage(struct pool *pp, struct pool_item_header *ph, struct pool_pagelist *pq) { int s; /* * If the page was idle, decrement the idle page count. */ if (ph->ph_nmissing == 0) { #ifdef DIAGNOSTIC if (pp->pr_nidle == 0) panic("pr_rmpage: nidle inconsistent"); if (pp->pr_nitems < pp->pr_itemsperpage) panic("pr_rmpage: nitems inconsistent"); #endif pp->pr_nidle--; } pp->pr_nitems -= pp->pr_itemsperpage; /* * Unlink a page from the pool and release it (or queue it for release). */ TAILQ_REMOVE(&pp->pr_pagelist, ph, ph_pagelist); if (pq) { TAILQ_INSERT_HEAD(pq, ph, ph_pagelist); } else { pool_allocator_free(pp, ph->ph_page); if ((pp->pr_roflags & PR_PHINPAGE) == 0) { LIST_REMOVE(ph, ph_hashlist); s = splhigh(); pool_put(&phpool, ph); splx(s); } } pp->pr_npages--; pp->pr_npagefree++; if (pp->pr_curpage == ph) { /* * Find a new non-empty page header, if any. * Start search from the page head, to increase the * chance for "high water" pages to be freed. */ TAILQ_FOREACH(ph, &pp->pr_pagelist, ph_pagelist) if (TAILQ_FIRST(&ph->ph_itemlist) != NULL) break; pp->pr_curpage = ph; } } /* * Initialize the given pool resource structure. * * We export this routine to allow other kernel parts to declare * static pools that must be initialized before malloc() is available. */ void pool_init(struct pool *pp, size_t size, u_int align, u_int ioff, int flags, const char *wchan, struct pool_allocator *palloc) { int off, slack, i; #ifdef POOL_DIAGNOSTIC /* * Always log if POOL_DIAGNOSTIC is defined. */ if (pool_logsize != 0) flags |= PR_LOGGING; #endif #ifdef POOL_SUBPAGE /* * XXX We don't provide a real `nointr' back-end * yet; all sub-pages come from a kmem back-end. * maybe some day... */ if (palloc == NULL) { extern struct pool_allocator pool_allocator_kmem_subpage; palloc = &pool_allocator_kmem_subpage; } /* * We'll assume any user-specified back-end allocator * will deal with sub-pages, or simply don't care. */ #else if (palloc == NULL) palloc = &pool_allocator_kmem; #endif /* POOL_SUBPAGE */ if ((palloc->pa_flags & PA_INITIALIZED) == 0) { if (palloc->pa_pagesz == 0) { #ifdef POOL_SUBPAGE if (palloc == &pool_allocator_kmem) palloc->pa_pagesz = PAGE_SIZE; else palloc->pa_pagesz = POOL_SUBPAGE; #else palloc->pa_pagesz = PAGE_SIZE; #endif /* POOL_SUBPAGE */ } TAILQ_INIT(&palloc->pa_list); simple_lock_init(&palloc->pa_slock); palloc->pa_pagemask = ~(palloc->pa_pagesz - 1); palloc->pa_pageshift = ffs(palloc->pa_pagesz) - 1; palloc->pa_flags |= PA_INITIALIZED; } if (align == 0) align = ALIGN(1); if (size < sizeof(struct pool_item)) size = sizeof(struct pool_item); size = ALIGN(size); #ifdef DIAGNOSTIC if (size > palloc->pa_pagesz) panic("pool_init: pool item size (%lu) too large", (u_long)size); #endif /* * Initialize the pool structure. */ TAILQ_INIT(&pp->pr_pagelist); TAILQ_INIT(&pp->pr_cachelist); pp->pr_curpage = NULL; pp->pr_npages = 0; pp->pr_minitems = 0; pp->pr_minpages = 0; pp->pr_maxpages = UINT_MAX; pp->pr_roflags = flags; pp->pr_flags = 0; pp->pr_size = size; pp->pr_align = align; pp->pr_wchan = wchan; pp->pr_alloc = palloc; pp->pr_nitems = 0; pp->pr_nout = 0; pp->pr_hardlimit = UINT_MAX; pp->pr_hardlimit_warning = NULL; pp->pr_hardlimit_ratecap.tv_sec = 0; pp->pr_hardlimit_ratecap.tv_usec = 0; pp->pr_hardlimit_warning_last.tv_sec = 0; pp->pr_hardlimit_warning_last.tv_usec = 0; pp->pr_drain_hook = NULL; pp->pr_drain_hook_arg = NULL; /* * Decide whether to put the page header off page to avoid * wasting too large a part of the page. Off-page page headers * go on a hash table, so we can match a returned item * with its header based on the page address. * We use 1/16 of the page size as the threshold (XXX: tune) */ if (pp->pr_size < palloc->pa_pagesz/16) { /* Use the end of the page for the page header */ pp->pr_roflags |= PR_PHINPAGE; pp->pr_phoffset = off = palloc->pa_pagesz - ALIGN(sizeof(struct pool_item_header)); } else { /* The page header will be taken from our page header pool */ pp->pr_phoffset = 0; off = palloc->pa_pagesz; for (i = 0; i < PR_HASHTABSIZE; i++) { LIST_INIT(&pp->pr_hashtab[i]); } } /* * Alignment is to take place at `ioff' within the item. This means * we must reserve up to `align - 1' bytes on the page to allow * appropriate positioning of each item. * * Silently enforce `0 <= ioff < align'. */ pp->pr_itemoffset = ioff = ioff % align; pp->pr_itemsperpage = (off - ((align - ioff) % align)) / pp->pr_size; KASSERT(pp->pr_itemsperpage != 0); /* * Use the slack between the chunks and the page header * for "cache coloring". */ slack = off - pp->pr_itemsperpage * pp->pr_size; pp->pr_maxcolor = (slack / align) * align; pp->pr_curcolor = 0; pp->pr_nget = 0; pp->pr_nfail = 0; pp->pr_nput = 0; pp->pr_npagealloc = 0; pp->pr_npagefree = 0; pp->pr_hiwat = 0; pp->pr_nidle = 0; #ifdef POOL_DIAGNOSTIC if (flags & PR_LOGGING) { if (kmem_map == NULL || (pp->pr_log = malloc(pool_logsize * sizeof(struct pool_log), M_TEMP, M_NOWAIT)) == NULL) pp->pr_roflags &= ~PR_LOGGING; pp->pr_curlogentry = 0; pp->pr_logsize = pool_logsize; } #endif pp->pr_entered_file = NULL; pp->pr_entered_line = 0; simple_lock_init(&pp->pr_slock); /* * Initialize private page header pool and cache magazine pool if we * haven't done so yet. * XXX LOCKING. */ if (phpool.pr_size == 0) { #ifdef POOL_SUBPAGE pool_init(&phpool, sizeof(struct pool_item_header), 0, 0, 0, "phpool", &pool_allocator_kmem); pool_init(&psppool, POOL_SUBPAGE, POOL_SUBPAGE, 0, PR_RECURSIVE, "psppool", &pool_allocator_kmem); #else pool_init(&phpool, sizeof(struct pool_item_header), 0, 0, 0, "phpool", NULL); #endif pool_init(&pcgpool, sizeof(struct pool_cache_group), 0, 0, 0, "pcgpool", NULL); } /* Insert into the list of all pools. */ simple_lock(&pool_head_slock); TAILQ_INSERT_TAIL(&pool_head, pp, pr_poollist); simple_unlock(&pool_head_slock); /* Insert this into the list of pools using this allocator. */ simple_lock(&palloc->pa_slock); TAILQ_INSERT_TAIL(&palloc->pa_list, pp, pr_alloc_list); simple_unlock(&palloc->pa_slock); } /* * De-commision a pool resource. */ void pool_destroy(struct pool *pp) { struct pool_item_header *ph; struct pool_cache *pc; /* Locking order: pool_allocator -> pool */ simple_lock(&pp->pr_alloc->pa_slock); TAILQ_REMOVE(&pp->pr_alloc->pa_list, pp, pr_alloc_list); simple_unlock(&pp->pr_alloc->pa_slock); /* Destroy all caches for this pool. */ while ((pc = TAILQ_FIRST(&pp->pr_cachelist)) != NULL) pool_cache_destroy(pc); #ifdef DIAGNOSTIC if (pp->pr_nout != 0) { pr_printlog(pp, NULL, printf); panic("pool_destroy: pool busy: still out: %u\n", pp->pr_nout); } #endif /* Remove all pages */ while ((ph = TAILQ_FIRST(&pp->pr_pagelist)) != NULL) pr_rmpage(pp, ph, NULL); /* Remove from global pool list */ simple_lock(&pool_head_slock); TAILQ_REMOVE(&pool_head, pp, pr_poollist); if (drainpp == pp) { drainpp = NULL; } simple_unlock(&pool_head_slock); #ifdef POOL_DIAGNOSTIC if ((pp->pr_roflags & PR_LOGGING) != 0) free(pp->pr_log, M_TEMP); #endif } void pool_set_drain_hook(struct pool *pp, void (*fn)(void *, int), void *arg) { /* XXX no locking -- must be used just after pool_init() */ #ifdef DIAGNOSTIC if (pp->pr_drain_hook != NULL) panic("pool_set_drain_hook(%s): already set", pp->pr_wchan); #endif pp->pr_drain_hook = fn; pp->pr_drain_hook_arg = arg; } static __inline struct pool_item_header * pool_alloc_item_header(struct pool *pp, caddr_t storage, int flags) { struct pool_item_header *ph; int s; LOCK_ASSERT(simple_lock_held(&pp->pr_slock) == 0); if ((pp->pr_roflags & PR_PHINPAGE) != 0) ph = (struct pool_item_header *) (storage + pp->pr_phoffset); else { s = splhigh(); ph = pool_get(&phpool, flags); splx(s); } return (ph); } /* * Grab an item from the pool; must be called at appropriate spl level */ void * #ifdef POOL_DIAGNOSTIC _pool_get(struct pool *pp, int flags, const char *file, long line) #else pool_get(struct pool *pp, int flags) #endif { struct pool_item *pi; struct pool_item_header *ph; void *v; #ifdef DIAGNOSTIC if (__predict_false(curproc == NULL && doing_shutdown == 0 && (flags & PR_WAITOK) != 0)) panic("pool_get: must have NOWAIT"); #ifdef LOCKDEBUG if (flags & PR_WAITOK) simple_lock_only_held(NULL, "pool_get(PR_WAITOK)"); #endif #endif /* DIAGNOSTIC */ simple_lock(&pp->pr_slock); pr_enter(pp, file, line); startover: /* * Check to see if we've reached the hard limit. If we have, * and we can wait, then wait until an item has been returned to * the pool. */ #ifdef DIAGNOSTIC if (__predict_false(pp->pr_nout > pp->pr_hardlimit)) { pr_leave(pp); simple_unlock(&pp->pr_slock); panic("pool_get: %s: crossed hard limit", pp->pr_wchan); } #endif if (__predict_false(pp->pr_nout == pp->pr_hardlimit)) { if (pp->pr_drain_hook != NULL) { /* * Since the drain hook is going to free things * back to the pool, unlock, call the hook, re-lock, * and check the hardlimit condition again. */ pr_leave(pp); simple_unlock(&pp->pr_slock); (*pp->pr_drain_hook)(pp->pr_drain_hook_arg, flags); simple_lock(&pp->pr_slock); pr_enter(pp, file, line); if (pp->pr_nout < pp->pr_hardlimit) goto startover; } if ((flags & PR_WAITOK) && !(flags & PR_LIMITFAIL)) { /* * XXX: A warning isn't logged in this case. Should * it be? */ pp->pr_flags |= PR_WANTED; pr_leave(pp); ltsleep(pp, PSWP, pp->pr_wchan, 0, &pp->pr_slock); pr_enter(pp, file, line); goto startover; } /* * Log a message that the hard limit has been hit. */ if (pp->pr_hardlimit_warning != NULL && ratecheck(&pp->pr_hardlimit_warning_last, &pp->pr_hardlimit_ratecap)) log(LOG_ERR, "%s\n", pp->pr_hardlimit_warning); pp->pr_nfail++; pr_leave(pp); simple_unlock(&pp->pr_slock); return (NULL); } /* * The convention we use is that if `curpage' is not NULL, then * it points at a non-empty bucket. In particular, `curpage' * never points at a page header which has PR_PHINPAGE set and * has no items in its bucket. */ if ((ph = pp->pr_curpage) == NULL) { #ifdef DIAGNOSTIC if (pp->pr_nitems != 0) { simple_unlock(&pp->pr_slock); printf("pool_get: %s: curpage NULL, nitems %u\n", pp->pr_wchan, pp->pr_nitems); panic("pool_get: nitems inconsistent\n"); } #endif /* * Call the back-end page allocator for more memory. * Release the pool lock, as the back-end page allocator * may block. */ pr_leave(pp); simple_unlock(&pp->pr_slock); v = pool_allocator_alloc(pp, flags); if (__predict_true(v != NULL)) ph = pool_alloc_item_header(pp, v, flags); simple_lock(&pp->pr_slock); pr_enter(pp, file, line); if (__predict_false(v == NULL || ph == NULL)) { if (v != NULL) pool_allocator_free(pp, v); /* * We were unable to allocate a page or item * header, but we released the lock during * allocation, so perhaps items were freed * back to the pool. Check for this case. */ if (pp->pr_curpage != NULL) goto startover; if ((flags & PR_WAITOK) == 0) { pp->pr_nfail++; pr_leave(pp); simple_unlock(&pp->pr_slock); return (NULL); } /* * Wait for items to be returned to this pool. * * XXX: maybe we should wake up once a second and * try again? */ pp->pr_flags |= PR_WANTED; /* PA_WANTED is already set on the allocator. */ pr_leave(pp); ltsleep(pp, PSWP, pp->pr_wchan, 0, &pp->pr_slock); pr_enter(pp, file, line); goto startover; } /* We have more memory; add it to the pool */ pool_prime_page(pp, v, ph); pp->pr_npagealloc++; /* Start the allocation process over. */ goto startover; } if (__predict_false((v = pi = TAILQ_FIRST(&ph->ph_itemlist)) == NULL)) { pr_leave(pp); simple_unlock(&pp->pr_slock); panic("pool_get: %s: page empty", pp->pr_wchan); } #ifdef DIAGNOSTIC if (__predict_false(pp->pr_nitems == 0)) { pr_leave(pp); simple_unlock(&pp->pr_slock); printf("pool_get: %s: items on itemlist, nitems %u\n", pp->pr_wchan, pp->pr_nitems); panic("pool_get: nitems inconsistent\n"); } #endif #ifdef POOL_DIAGNOSTIC pr_log(pp, v, PRLOG_GET, file, line); #endif #ifdef DIAGNOSTIC if (__predict_false(pi->pi_magic != PI_MAGIC)) { pr_printlog(pp, pi, printf); panic("pool_get(%s): free list modified: magic=%x; page %p;" " item addr %p\n", pp->pr_wchan, pi->pi_magic, ph->ph_page, pi); } #endif /* * Remove from item list. */ TAILQ_REMOVE(&ph->ph_itemlist, pi, pi_list); pp->pr_nitems--; pp->pr_nout++; if (ph->ph_nmissing == 0) { #ifdef DIAGNOSTIC if (__predict_false(pp->pr_nidle == 0)) panic("pool_get: nidle inconsistent"); #endif pp->pr_nidle--; } ph->ph_nmissing++; if (TAILQ_FIRST(&ph->ph_itemlist) == NULL) { #ifdef DIAGNOSTIC if (__predict_false(ph->ph_nmissing != pp->pr_itemsperpage)) { pr_leave(pp); simple_unlock(&pp->pr_slock); panic("pool_get: %s: nmissing inconsistent", pp->pr_wchan); } #endif /* * Find a new non-empty page header, if any. * Start search from the page head, to increase * the chance for "high water" pages to be freed. * * Migrate empty pages to the end of the list. This * will speed the update of curpage as pages become * idle. Empty pages intermingled with idle pages * is no big deal. As soon as a page becomes un-empty, * it will move back to the head of the list. */ TAILQ_REMOVE(&pp->pr_pagelist, ph, ph_pagelist); TAILQ_INSERT_TAIL(&pp->pr_pagelist, ph, ph_pagelist); TAILQ_FOREACH(ph, &pp->pr_pagelist, ph_pagelist) if (TAILQ_FIRST(&ph->ph_itemlist) != NULL) break; pp->pr_curpage = ph; } pp->pr_nget++; /* * If we have a low water mark and we are now below that low * water mark, add more items to the pool. */ if (POOL_NEEDS_CATCHUP(pp) && pool_catchup(pp) != 0) { /* * XXX: Should we log a warning? Should we set up a timeout * to try again in a second or so? The latter could break * a caller's assumptions about interrupt protection, etc. */ } pr_leave(pp); simple_unlock(&pp->pr_slock); return (v); } /* * Internal version of pool_put(). Pool is already locked/entered. */ static void pool_do_put(struct pool *pp, void *v) { struct pool_item *pi = v; struct pool_item_header *ph; caddr_t page; int s; LOCK_ASSERT(simple_lock_held(&pp->pr_slock)); page = (caddr_t)((u_long)v & pp->pr_alloc->pa_pagemask); #ifdef DIAGNOSTIC if (__predict_false(pp->pr_nout == 0)) { printf("pool %s: putting with none out\n", pp->pr_wchan); panic("pool_put"); } #endif if (__predict_false((ph = pr_find_pagehead(pp, page)) == NULL)) { pr_printlog(pp, NULL, printf); panic("pool_put: %s: page header missing", pp->pr_wchan); } #ifdef LOCKDEBUG /* * Check if we're freeing a locked simple lock. */ simple_lock_freecheck((caddr_t)pi, ((caddr_t)pi) + pp->pr_size); #endif /* * Return to item list. */ #ifdef DIAGNOSTIC pi->pi_magic = PI_MAGIC; #endif #ifdef DEBUG { int i, *ip = v; for (i = 0; i < pp->pr_size / sizeof(int); i++) { *ip++ = PI_MAGIC; } } #endif TAILQ_INSERT_HEAD(&ph->ph_itemlist, pi, pi_list); ph->ph_nmissing--; pp->pr_nput++; pp->pr_nitems++; pp->pr_nout--; /* Cancel "pool empty" condition if it exists */ if (pp->pr_curpage == NULL) pp->pr_curpage = ph; if (pp->pr_flags & PR_WANTED) { pp->pr_flags &= ~PR_WANTED; if (ph->ph_nmissing == 0) pp->pr_nidle++; wakeup((caddr_t)pp); return; } /* * If this page is now complete, do one of two things: * * (1) If we have more pages than the page high water * mark, free the page back to the system. * * (2) Move it to the end of the page list, so that * we minimize our chances of fragmenting the * pool. Idle pages migrate to the end (along with * completely empty pages, so that we find un-empty * pages more quickly when we update curpage) of the * list so they can be more easily swept up by * the pagedaemon when pages are scarce. */ if (ph->ph_nmissing == 0) { pp->pr_nidle++; if (pp->pr_npages > pp->pr_maxpages || (pp->pr_alloc->pa_flags & PA_WANT) != 0) { pr_rmpage(pp, ph, NULL); } else { TAILQ_REMOVE(&pp->pr_pagelist, ph, ph_pagelist); TAILQ_INSERT_TAIL(&pp->pr_pagelist, ph, ph_pagelist); /* * Update the timestamp on the page. A page must * be idle for some period of time before it can * be reclaimed by the pagedaemon. This minimizes * ping-pong'ing for memory. */ s = splclock(); ph->ph_time = mono_time; splx(s); /* * Update the current page pointer. Just look for * the first page with any free items. * * XXX: Maybe we want an option to look for the * page with the fewest available items, to minimize * fragmentation? */ TAILQ_FOREACH(ph, &pp->pr_pagelist, ph_pagelist) if (TAILQ_FIRST(&ph->ph_itemlist) != NULL) break; pp->pr_curpage = ph; } } /* * If the page has just become un-empty, move it to the head of * the list, and make it the current page. The next allocation * will get the item from this page, instead of further fragmenting * the pool. */ else if (ph->ph_nmissing == (pp->pr_itemsperpage - 1)) { TAILQ_REMOVE(&pp->pr_pagelist, ph, ph_pagelist); TAILQ_INSERT_HEAD(&pp->pr_pagelist, ph, ph_pagelist); pp->pr_curpage = ph; } } /* * Return resource to the pool; must be called at appropriate spl level */ #ifdef POOL_DIAGNOSTIC void _pool_put(struct pool *pp, void *v, const char *file, long line) { simple_lock(&pp->pr_slock); pr_enter(pp, file, line); pr_log(pp, v, PRLOG_PUT, file, line); pool_do_put(pp, v); pr_leave(pp); simple_unlock(&pp->pr_slock); } #undef pool_put #endif /* POOL_DIAGNOSTIC */ void pool_put(struct pool *pp, void *v) { simple_lock(&pp->pr_slock); pool_do_put(pp, v); simple_unlock(&pp->pr_slock); } #ifdef POOL_DIAGNOSTIC #define pool_put(h, v) _pool_put((h), (v), __FILE__, __LINE__) #endif /* * Add N items to the pool. */ int pool_prime(struct pool *pp, int n) { struct pool_item_header *ph; caddr_t cp; int newpages; simple_lock(&pp->pr_slock); newpages = roundup(n, pp->pr_itemsperpage) / pp->pr_itemsperpage; while (newpages-- > 0) { simple_unlock(&pp->pr_slock); cp = pool_allocator_alloc(pp, PR_NOWAIT); if (__predict_true(cp != NULL)) ph = pool_alloc_item_header(pp, cp, PR_NOWAIT); simple_lock(&pp->pr_slock); if (__predict_false(cp == NULL || ph == NULL)) { if (cp != NULL) pool_allocator_free(pp, cp); break; } pool_prime_page(pp, cp, ph); pp->pr_npagealloc++; pp->pr_minpages++; } if (pp->pr_minpages >= pp->pr_maxpages) pp->pr_maxpages = pp->pr_minpages + 1; /* XXX */ simple_unlock(&pp->pr_slock); return (0); } /* * Add a page worth of items to the pool. * * Note, we must be called with the pool descriptor LOCKED. */ static void pool_prime_page(struct pool *pp, caddr_t storage, struct pool_item_header *ph) { struct pool_item *pi; caddr_t cp = storage; unsigned int align = pp->pr_align; unsigned int ioff = pp->pr_itemoffset; int n; #ifdef DIAGNOSTIC if (((u_long)cp & (pp->pr_alloc->pa_pagesz - 1)) != 0) panic("pool_prime_page: %s: unaligned page", pp->pr_wchan); #endif if ((pp->pr_roflags & PR_PHINPAGE) == 0) LIST_INSERT_HEAD(&pp->pr_hashtab[PR_HASH_INDEX(pp, cp)], ph, ph_hashlist); /* * Insert page header. */ TAILQ_INSERT_HEAD(&pp->pr_pagelist, ph, ph_pagelist); TAILQ_INIT(&ph->ph_itemlist); ph->ph_page = storage; ph->ph_nmissing = 0; memset(&ph->ph_time, 0, sizeof(ph->ph_time)); pp->pr_nidle++; /* * Color this page. */ cp = (caddr_t)(cp + pp->pr_curcolor); if ((pp->pr_curcolor += align) > pp->pr_maxcolor) pp->pr_curcolor = 0; /* * Adjust storage to apply aligment to `pr_itemoffset' in each item. */ if (ioff != 0) cp = (caddr_t)(cp + (align - ioff)); /* * Insert remaining chunks on the bucket list. */ n = pp->pr_itemsperpage; pp->pr_nitems += n; while (n--) { pi = (struct pool_item *)cp; /* Insert on page list */ TAILQ_INSERT_TAIL(&ph->ph_itemlist, pi, pi_list); #ifdef DIAGNOSTIC pi->pi_magic = PI_MAGIC; #endif cp = (caddr_t)(cp + pp->pr_size); } /* * If the pool was depleted, point at the new page. */ if (pp->pr_curpage == NULL) pp->pr_curpage = ph; if (++pp->pr_npages > pp->pr_hiwat) pp->pr_hiwat = pp->pr_npages; } /* * Used by pool_get() when nitems drops below the low water mark. This * is used to catch up nitmes with the low water mark. * * Note 1, we never wait for memory here, we let the caller decide what to do. * * Note 2, we must be called with the pool already locked, and we return * with it locked. */ static int pool_catchup(struct pool *pp) { struct pool_item_header *ph; caddr_t cp; int error = 0; while (POOL_NEEDS_CATCHUP(pp)) { /* * Call the page back-end allocator for more memory. * * XXX: We never wait, so should we bother unlocking * the pool descriptor? */ simple_unlock(&pp->pr_slock); cp = pool_allocator_alloc(pp, PR_NOWAIT); if (__predict_true(cp != NULL)) ph = pool_alloc_item_header(pp, cp, PR_NOWAIT); simple_lock(&pp->pr_slock); if (__predict_false(cp == NULL || ph == NULL)) { if (cp != NULL) pool_allocator_free(pp, cp); error = ENOMEM; break; } pool_prime_page(pp, cp, ph); pp->pr_npagealloc++; } return (error); } void pool_setlowat(struct pool *pp, int n) { simple_lock(&pp->pr_slock); pp->pr_minitems = n; pp->pr_minpages = (n == 0) ? 0 : roundup(n, pp->pr_itemsperpage) / pp->pr_itemsperpage; /* Make sure we're caught up with the newly-set low water mark. */ if (POOL_NEEDS_CATCHUP(pp) && pool_catchup(pp) != 0) { /* * XXX: Should we log a warning? Should we set up a timeout * to try again in a second or so? The latter could break * a caller's assumptions about interrupt protection, etc. */ } simple_unlock(&pp->pr_slock); } void pool_sethiwat(struct pool *pp, int n) { simple_lock(&pp->pr_slock); pp->pr_maxpages = (n == 0) ? 0 : roundup(n, pp->pr_itemsperpage) / pp->pr_itemsperpage; simple_unlock(&pp->pr_slock); } void pool_sethardlimit(struct pool *pp, int n, const char *warnmess, int ratecap) { simple_lock(&pp->pr_slock); pp->pr_hardlimit = n; pp->pr_hardlimit_warning = warnmess; pp->pr_hardlimit_ratecap.tv_sec = ratecap; pp->pr_hardlimit_warning_last.tv_sec = 0; pp->pr_hardlimit_warning_last.tv_usec = 0; /* * In-line version of pool_sethiwat(), because we don't want to * release the lock. */ pp->pr_maxpages = (n == 0) ? 0 : roundup(n, pp->pr_itemsperpage) / pp->pr_itemsperpage; simple_unlock(&pp->pr_slock); } /* * Release all complete pages that have not been used recently. */ int #ifdef POOL_DIAGNOSTIC _pool_reclaim(struct pool *pp, const char *file, long line) #else pool_reclaim(struct pool *pp) #endif { struct pool_item_header *ph, *phnext; struct pool_cache *pc; struct timeval curtime; struct pool_pagelist pq; int s; if (pp->pr_drain_hook != NULL) { /* * The drain hook must be called with the pool unlocked. */ (*pp->pr_drain_hook)(pp->pr_drain_hook_arg, PR_NOWAIT); } if (simple_lock_try(&pp->pr_slock) == 0) return (0); pr_enter(pp, file, line); TAILQ_INIT(&pq); /* * Reclaim items from the pool's caches. */ TAILQ_FOREACH(pc, &pp->pr_cachelist, pc_poollist) pool_cache_reclaim(pc); s = splclock(); curtime = mono_time; splx(s); for (ph = TAILQ_FIRST(&pp->pr_pagelist); ph != NULL; ph = phnext) { phnext = TAILQ_NEXT(ph, ph_pagelist); /* Check our minimum page claim */ if (pp->pr_npages <= pp->pr_minpages) break; if (ph->ph_nmissing == 0) { struct timeval diff; timersub(&curtime, &ph->ph_time, &diff); if (diff.tv_sec < pool_inactive_time) continue; /* * If freeing this page would put us below * the low water mark, stop now. */ if ((pp->pr_nitems - pp->pr_itemsperpage) < pp->pr_minitems) break; pr_rmpage(pp, ph, &pq); } } pr_leave(pp); simple_unlock(&pp->pr_slock); if (TAILQ_EMPTY(&pq)) return (0); while ((ph = TAILQ_FIRST(&pq)) != NULL) { TAILQ_REMOVE(&pq, ph, ph_pagelist); pool_allocator_free(pp, ph->ph_page); if (pp->pr_roflags & PR_PHINPAGE) { continue; } LIST_REMOVE(ph, ph_hashlist); s = splhigh(); pool_put(&phpool, ph); splx(s); } return (1); } /* * Drain pools, one at a time. * * Note, we must never be called from an interrupt context. */ void pool_drain(void *arg) { struct pool *pp; int s; pp = NULL; s = splvm(); simple_lock(&pool_head_slock); if (drainpp == NULL) { drainpp = TAILQ_FIRST(&pool_head); } if (drainpp) { pp = drainpp; drainpp = TAILQ_NEXT(pp, pr_poollist); } simple_unlock(&pool_head_slock); pool_reclaim(pp); splx(s); } /* * Diagnostic helpers. */ void pool_print(struct pool *pp, const char *modif) { int s; s = splvm(); if (simple_lock_try(&pp->pr_slock) == 0) { printf("pool %s is locked; try again later\n", pp->pr_wchan); splx(s); return; } pool_print1(pp, modif, printf); simple_unlock(&pp->pr_slock); splx(s); } void pool_printit(struct pool *pp, const char *modif, void (*pr)(const char *, ...)) { int didlock = 0; if (pp == NULL) { (*pr)("Must specify a pool to print.\n"); return; } /* * Called from DDB; interrupts should be blocked, and all * other processors should be paused. We can skip locking * the pool in this case. * * We do a simple_lock_try() just to print the lock * status, however. */ if (simple_lock_try(&pp->pr_slock) == 0) (*pr)("WARNING: pool %s is locked\n", pp->pr_wchan); else didlock = 1; pool_print1(pp, modif, pr); if (didlock) simple_unlock(&pp->pr_slock); } static void pool_print1(struct pool *pp, const char *modif, void (*pr)(const char *, ...)) { struct pool_item_header *ph; struct pool_cache *pc; struct pool_cache_group *pcg; #ifdef DIAGNOSTIC struct pool_item *pi; #endif int i, print_log = 0, print_pagelist = 0, print_cache = 0; char c; while ((c = *modif++) != '\0') { if (c == 'l') print_log = 1; if (c == 'p') print_pagelist = 1; if (c == 'c') print_cache = 1; modif++; } (*pr)("POOL %s: size %u, align %u, ioff %u, roflags 0x%08x\n", pp->pr_wchan, pp->pr_size, pp->pr_align, pp->pr_itemoffset, pp->pr_roflags); (*pr)("\talloc %p\n", pp->pr_alloc); (*pr)("\tminitems %u, minpages %u, maxpages %u, npages %u\n", pp->pr_minitems, pp->pr_minpages, pp->pr_maxpages, pp->pr_npages); (*pr)("\titemsperpage %u, nitems %u, nout %u, hardlimit %u\n", pp->pr_itemsperpage, pp->pr_nitems, pp->pr_nout, pp->pr_hardlimit); (*pr)("\n\tnget %lu, nfail %lu, nput %lu\n", pp->pr_nget, pp->pr_nfail, pp->pr_nput); (*pr)("\tnpagealloc %lu, npagefree %lu, hiwat %u, nidle %lu\n", pp->pr_npagealloc, pp->pr_npagefree, pp->pr_hiwat, pp->pr_nidle); if (print_pagelist == 0) goto skip_pagelist; if ((ph = TAILQ_FIRST(&pp->pr_pagelist)) != NULL) (*pr)("\n\tpage list:\n"); for (; ph != NULL; ph = TAILQ_NEXT(ph, ph_pagelist)) { (*pr)("\t\tpage %p, nmissing %d, time %lu,%lu\n", ph->ph_page, ph->ph_nmissing, (u_long)ph->ph_time.tv_sec, (u_long)ph->ph_time.tv_usec); #ifdef DIAGNOSTIC TAILQ_FOREACH(pi, &ph->ph_itemlist, pi_list) { if (pi->pi_magic != PI_MAGIC) { (*pr)("\t\t\titem %p, magic 0x%x\n", pi, pi->pi_magic); } } #endif } if (pp->pr_curpage == NULL) (*pr)("\tno current page\n"); else (*pr)("\tcurpage %p\n", pp->pr_curpage->ph_page); skip_pagelist: if (print_log == 0) goto skip_log; (*pr)("\n"); if ((pp->pr_roflags & PR_LOGGING) == 0) (*pr)("\tno log\n"); else pr_printlog(pp, NULL, pr); skip_log: if (print_cache == 0) goto skip_cache; TAILQ_FOREACH(pc, &pp->pr_cachelist, pc_poollist) { (*pr)("\tcache %p: allocfrom %p freeto %p\n", pc, pc->pc_allocfrom, pc->pc_freeto); (*pr)("\t hits %lu misses %lu ngroups %lu nitems %lu\n", pc->pc_hits, pc->pc_misses, pc->pc_ngroups, pc->pc_nitems); TAILQ_FOREACH(pcg, &pc->pc_grouplist, pcg_list) { (*pr)("\t\tgroup %p: avail %d\n", pcg, pcg->pcg_avail); for (i = 0; i < PCG_NOBJECTS; i++) (*pr)("\t\t\t%p\n", pcg->pcg_objects[i]); } } skip_cache: pr_enter_check(pp, pr); } int pool_chk(struct pool *pp, const char *label) { struct pool_item_header *ph; int r = 0; simple_lock(&pp->pr_slock); TAILQ_FOREACH(ph, &pp->pr_pagelist, ph_pagelist) { struct pool_item *pi; int n; caddr_t page; page = (caddr_t)((u_long)ph & pp->pr_alloc->pa_pagemask); if (page != ph->ph_page && (pp->pr_roflags & PR_PHINPAGE) != 0) { if (label != NULL) printf("%s: ", label); printf("pool(%p:%s): page inconsistency: page %p;" " at page head addr %p (p %p)\n", pp, pp->pr_wchan, ph->ph_page, ph, page); r++; goto out; } for (pi = TAILQ_FIRST(&ph->ph_itemlist), n = 0; pi != NULL; pi = TAILQ_NEXT(pi,pi_list), n++) { #ifdef DIAGNOSTIC if (pi->pi_magic != PI_MAGIC) { if (label != NULL) printf("%s: ", label); printf("pool(%s): free list modified: magic=%x;" " page %p; item ordinal %d;" " addr %p (p %p)\n", pp->pr_wchan, pi->pi_magic, ph->ph_page, n, pi, page); panic("pool"); } #endif page = (caddr_t)((u_long)pi & pp->pr_alloc->pa_pagemask); if (page == ph->ph_page) continue; if (label != NULL) printf("%s: ", label); printf("pool(%p:%s): page inconsistency: page %p;" " item ordinal %d; addr %p (p %p)\n", pp, pp->pr_wchan, ph->ph_page, n, pi, page); r++; goto out; } } out: simple_unlock(&pp->pr_slock); return (r); } /* * pool_cache_init: * * Initialize a pool cache. * * NOTE: If the pool must be protected from interrupts, we expect * to be called at the appropriate interrupt priority level. */ void pool_cache_init(struct pool_cache *pc, struct pool *pp, int (*ctor)(void *, void *, int), void (*dtor)(void *, void *), void *arg) { TAILQ_INIT(&pc->pc_grouplist); simple_lock_init(&pc->pc_slock); pc->pc_allocfrom = NULL; pc->pc_freeto = NULL; pc->pc_pool = pp; pc->pc_ctor = ctor; pc->pc_dtor = dtor; pc->pc_arg = arg; pc->pc_hits = 0; pc->pc_misses = 0; pc->pc_ngroups = 0; pc->pc_nitems = 0; simple_lock(&pp->pr_slock); TAILQ_INSERT_TAIL(&pp->pr_cachelist, pc, pc_poollist); simple_unlock(&pp->pr_slock); } /* * pool_cache_destroy: * * Destroy a pool cache. */ void pool_cache_destroy(struct pool_cache *pc) { struct pool *pp = pc->pc_pool; /* First, invalidate the entire cache. */ pool_cache_invalidate(pc); /* ...and remove it from the pool's cache list. */ simple_lock(&pp->pr_slock); TAILQ_REMOVE(&pp->pr_cachelist, pc, pc_poollist); simple_unlock(&pp->pr_slock); } static __inline void * pcg_get(struct pool_cache_group *pcg) { void *object; u_int idx; KASSERT(pcg->pcg_avail <= PCG_NOBJECTS); KASSERT(pcg->pcg_avail != 0); idx = --pcg->pcg_avail; KASSERT(pcg->pcg_objects[idx] != NULL); object = pcg->pcg_objects[idx]; pcg->pcg_objects[idx] = NULL; return (object); } static __inline void pcg_put(struct pool_cache_group *pcg, void *object) { u_int idx; KASSERT(pcg->pcg_avail < PCG_NOBJECTS); idx = pcg->pcg_avail++; KASSERT(pcg->pcg_objects[idx] == NULL); pcg->pcg_objects[idx] = object; } /* * pool_cache_get: * * Get an object from a pool cache. */ void * pool_cache_get(struct pool_cache *pc, int flags) { struct pool_cache_group *pcg; void *object; #ifdef LOCKDEBUG if (flags & PR_WAITOK) simple_lock_only_held(NULL, "pool_cache_get(PR_WAITOK)"); #endif simple_lock(&pc->pc_slock); if ((pcg = pc->pc_allocfrom) == NULL) { TAILQ_FOREACH(pcg, &pc->pc_grouplist, pcg_list) { if (pcg->pcg_avail != 0) { pc->pc_allocfrom = pcg; goto have_group; } } /* * No groups with any available objects. Allocate * a new object, construct it, and return it to * the caller. We will allocate a group, if necessary, * when the object is freed back to the cache. */ pc->pc_misses++; simple_unlock(&pc->pc_slock); object = pool_get(pc->pc_pool, flags); if (object != NULL && pc->pc_ctor != NULL) { if ((*pc->pc_ctor)(pc->pc_arg, object, flags) != 0) { pool_put(pc->pc_pool, object); return (NULL); } } return (object); } have_group: pc->pc_hits++; pc->pc_nitems--; object = pcg_get(pcg); if (pcg->pcg_avail == 0) pc->pc_allocfrom = NULL; simple_unlock(&pc->pc_slock); return (object); } /* * pool_cache_put: * * Put an object back to the pool cache. */ void pool_cache_put(struct pool_cache *pc, void *object) { struct pool_cache_group *pcg; int s; simple_lock(&pc->pc_slock); if ((pcg = pc->pc_freeto) == NULL) { TAILQ_FOREACH(pcg, &pc->pc_grouplist, pcg_list) { if (pcg->pcg_avail != PCG_NOBJECTS) { pc->pc_freeto = pcg; goto have_group; } } /* * No empty groups to free the object to. Attempt to * allocate one. */ simple_unlock(&pc->pc_slock); s = splvm(); pcg = pool_get(&pcgpool, PR_NOWAIT); splx(s); if (pcg != NULL) { memset(pcg, 0, sizeof(*pcg)); simple_lock(&pc->pc_slock); pc->pc_ngroups++; TAILQ_INSERT_TAIL(&pc->pc_grouplist, pcg, pcg_list); if (pc->pc_freeto == NULL) pc->pc_freeto = pcg; goto have_group; } /* * Unable to allocate a cache group; destruct the object * and free it back to the pool. */ pool_cache_destruct_object(pc, object); return; } have_group: pc->pc_nitems++; pcg_put(pcg, object); if (pcg->pcg_avail == PCG_NOBJECTS) pc->pc_freeto = NULL; simple_unlock(&pc->pc_slock); } /* * pool_cache_destruct_object: * * Force destruction of an object and its release back into * the pool. */ void pool_cache_destruct_object(struct pool_cache *pc, void *object) { if (pc->pc_dtor != NULL) (*pc->pc_dtor)(pc->pc_arg, object); pool_put(pc->pc_pool, object); } /* * pool_cache_do_invalidate: * * This internal function implements pool_cache_invalidate() and * pool_cache_reclaim(). */ static void pool_cache_do_invalidate(struct pool_cache *pc, int free_groups, void (*putit)(struct pool *, void *)) { struct pool_cache_group *pcg, *npcg; void *object; int s; for (pcg = TAILQ_FIRST(&pc->pc_grouplist); pcg != NULL; pcg = npcg) { npcg = TAILQ_NEXT(pcg, pcg_list); while (pcg->pcg_avail != 0) { pc->pc_nitems--; object = pcg_get(pcg); if (pcg->pcg_avail == 0 && pc->pc_allocfrom == pcg) pc->pc_allocfrom = NULL; if (pc->pc_dtor != NULL) (*pc->pc_dtor)(pc->pc_arg, object); (*putit)(pc->pc_pool, object); } if (free_groups) { pc->pc_ngroups--; TAILQ_REMOVE(&pc->pc_grouplist, pcg, pcg_list); if (pc->pc_freeto == pcg) pc->pc_freeto = NULL; s = splvm(); pool_put(&pcgpool, pcg); splx(s); } } } /* * pool_cache_invalidate: * * Invalidate a pool cache (destruct and release all of the * cached objects). */ void pool_cache_invalidate(struct pool_cache *pc) { simple_lock(&pc->pc_slock); pool_cache_do_invalidate(pc, 0, pool_put); simple_unlock(&pc->pc_slock); } /* * pool_cache_reclaim: * * Reclaim a pool cache for pool_reclaim(). */ static void pool_cache_reclaim(struct pool_cache *pc) { simple_lock(&pc->pc_slock); pool_cache_do_invalidate(pc, 1, pool_do_put); simple_unlock(&pc->pc_slock); } /* * Pool backend allocators. * * Each pool has a backend allocator that handles allocation, deallocation, * and any additional draining that might be needed. * * We provide two standard allocators: * * pool_allocator_kmem - the default when no allocator is specified * * pool_allocator_nointr - used for pools that will not be accessed * in interrupt context. */ void *pool_page_alloc(struct pool *, int); void pool_page_free(struct pool *, void *); struct pool_allocator pool_allocator_kmem = { pool_page_alloc, pool_page_free, 0, }; void *pool_page_alloc_nointr(struct pool *, int); void pool_page_free_nointr(struct pool *, void *); struct pool_allocator pool_allocator_nointr = { pool_page_alloc_nointr, pool_page_free_nointr, 0, }; #ifdef POOL_SUBPAGE void *pool_subpage_alloc(struct pool *, int); void pool_subpage_free(struct pool *, void *); struct pool_allocator pool_allocator_kmem_subpage = { pool_subpage_alloc, pool_subpage_free, 0, }; #endif /* POOL_SUBPAGE */ /* * We have at least three different resources for the same allocation and * each resource can be depleted. First, we have the ready elements in the * pool. Then we have the resource (typically a vm_map) for this allocator. * Finally, we have physical memory. Waiting for any of these can be * unnecessary when any other is freed, but the kernel doesn't support * sleeping on multiple wait channels, so we have to employ another strategy. * * The caller sleeps on the pool (so that it can be awakened when an item * is returned to the pool), but we set PA_WANT on the allocator. When a * page is returned to the allocator and PA_WANT is set, pool_allocator_free * will wake up all sleeping pools belonging to this allocator. * * XXX Thundering herd. */ void * pool_allocator_alloc(struct pool *org, int flags) { struct pool_allocator *pa = org->pr_alloc; struct pool *pp, *start; int s, freed; void *res; do { if ((res = (*pa->pa_alloc)(org, flags)) != NULL) return (res); if ((flags & PR_WAITOK) == 0) { /* * We only run the drain hookhere if PR_NOWAIT. * In other cases, the hook will be run in * pool_reclaim(). */ if (org->pr_drain_hook != NULL) { (*org->pr_drain_hook)(org->pr_drain_hook_arg, flags); if ((res = (*pa->pa_alloc)(org, flags)) != NULL) return (res); } break; } /* * Drain all pools, except "org", that use this * allocator. We do this to reclaim VA space. * pa_alloc is responsible for waiting for * physical memory. * * XXX We risk looping forever if start if someone * calls pool_destroy on "start". But there is no * other way to have potentially sleeping pool_reclaim, * non-sleeping locks on pool_allocator, and some * stirring of drained pools in the allocator. * * XXX Maybe we should use pool_head_slock for locking * the allocators? */ freed = 0; s = splvm(); simple_lock(&pa->pa_slock); pp = start = TAILQ_FIRST(&pa->pa_list); do { TAILQ_REMOVE(&pa->pa_list, pp, pr_alloc_list); TAILQ_INSERT_TAIL(&pa->pa_list, pp, pr_alloc_list); if (pp == org) continue; simple_unlock(&pa->pa_slock); freed = pool_reclaim(pp); simple_lock(&pa->pa_slock); } while ((pp = TAILQ_FIRST(&pa->pa_list)) != start && freed == 0); if (freed == 0) { /* * We set PA_WANT here, the caller will most likely * sleep waiting for pages (if not, this won't hurt * that much), and there is no way to set this in * the caller without violating locking order. */ pa->pa_flags |= PA_WANT; } simple_unlock(&pa->pa_slock); splx(s); } while (freed); return (NULL); } void pool_allocator_free(struct pool *pp, void *v) { struct pool_allocator *pa = pp->pr_alloc; int s; (*pa->pa_free)(pp, v); s = splvm(); simple_lock(&pa->pa_slock); if ((pa->pa_flags & PA_WANT) == 0) { simple_unlock(&pa->pa_slock); splx(s); return; } TAILQ_FOREACH(pp, &pa->pa_list, pr_alloc_list) { simple_lock(&pp->pr_slock); if ((pp->pr_flags & PR_WANTED) != 0) { pp->pr_flags &= ~PR_WANTED; wakeup(pp); } simple_unlock(&pp->pr_slock); } pa->pa_flags &= ~PA_WANT; simple_unlock(&pa->pa_slock); splx(s); } void * pool_page_alloc(struct pool *pp, int flags) { boolean_t waitok = (flags & PR_WAITOK) ? TRUE : FALSE; return ((void *) uvm_km_alloc_poolpage(waitok)); } void pool_page_free(struct pool *pp, void *v) { uvm_km_free_poolpage((vaddr_t) v); } #ifdef POOL_SUBPAGE /* Sub-page allocator, for machines with large hardware pages. */ void * pool_subpage_alloc(struct pool *pp, int flags) { return (pool_get(&psppool, flags)); } void pool_subpage_free(struct pool *pp, void *v) { pool_put(&psppool, v); } /* We don't provide a real nointr allocator. Maybe later. */ void * pool_page_alloc_nointr(struct pool *pp, int flags) { return (pool_subpage_alloc(pp, flags)); } void pool_page_free_nointr(struct pool *pp, void *v) { pool_subpage_free(pp, v); } #else void * pool_page_alloc_nointr(struct pool *pp, int flags) { boolean_t waitok = (flags & PR_WAITOK) ? TRUE : FALSE; return ((void *) uvm_km_alloc_poolpage1(kernel_map, uvm.kernel_object, waitok)); } void pool_page_free_nointr(struct pool *pp, void *v) { uvm_km_free_poolpage1(kernel_map, (vaddr_t) v); } #endif /* POOL_SUBPAGE */