Please note that diffs are not public domain; they are subject to the copyright notices on the relevant files. =================================================================== RCS file: /ftp/cvs/cvsroot/src/sys/kern/subr_pool.c,v rcsdiff: /ftp/cvs/cvsroot/src/sys/kern/subr_pool.c,v: warning: Unknown phrases like `commitid ...;' are present. retrieving revision 1.1 retrieving revision 1.82 diff -u -p -r1.1 -r1.82 --- src/sys/kern/subr_pool.c 1997/12/15 11:14:57 1.1 +++ src/sys/kern/subr_pool.c 2002/11/09 20:12:55 1.82 @@ -1,11 +1,12 @@ -/* $NetBSD: subr_pool.c,v 1.1 1997/12/15 11:14:57 pk Exp $ */ +/* $NetBSD: subr_pool.c,v 1.82 2002/11/09 20:12:55 thorpej Exp $ */ /*- - * Copyright (c) 1997 The NetBSD Foundation, Inc. + * 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 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 @@ -17,8 +18,8 @@ * 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. + * 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. @@ -36,6 +37,13 @@ * POSSIBILITY OF SUCH DAMAGE. */ +#include +__KERNEL_RCSID(0, "$NetBSD: subr_pool.c,v 1.82 2002/11/09 20:12:55 thorpej Exp $"); + +#include "opt_pool.h" +#include "opt_poollog.h" +#include "opt_lockdebug.h" + #include #include #include @@ -44,164 +52,2007 @@ #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 */ + unsigned 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 { - struct pool_item *pi_next; +#ifdef DIAGNOSTIC + u_int pi_magic; +#endif +#define PI_MAGIC 0xdeadbeefU + /* 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; -struct pool * -pool_create(size, nitems, wchan, mtype) - size_t size; - int nitems; - char *wchan; - int mtype; + /* + * 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 *, ...)) { - struct pool *pp; + int i = pp->pr_logsize; + int n = pp->pr_curlogentry; - if (size < sizeof(struct pool_item)) { - printf("pool_create: size %lu too small\n", (u_long)size); - return (NULL); + 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; } +} - pp = (struct pool *)malloc(sizeof(*pp), mtype, M_NOWAIT); - if (pp == NULL) - return (NULL); +static __inline void +pr_enter(struct pool *pp, const char *file, long line) +{ - pp->pr_freelist = NULL; - pp->pr_freecount = 0; - pp->pr_hiwat = 0; + 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 = roundup(size, align); +#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_mtype = mtype; - simple_lock_init(&pp->pr_lock); + 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]); + } + } - if (nitems != 0) { - if (pool_prime(pp, nitems) != 0) - pool_destroy(pp); - return (NULL); + /* + * 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); } - return (pp); + /* 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(pp) - struct pool *pp; +pool_destroy(struct pool *pp) { - struct pool_item *pi; + 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", + pp->pr_nout); + } +#endif - while ((pi = pp->pr_freelist) != NULL) { - pp->pr_freelist = pi->pi_next; - free(pi, pp->pr_mtype); + /* 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; } - free(pp, pp->pr_mtype); + 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 splbio + * Grab an item from the pool; must be called at appropriate spl level */ void * -pool_get(pp, flags) - struct pool *pp; - int flags; +#ifdef POOL_DIAGNOSTIC +_pool_get(struct pool *pp, int flags, const char *file, long line) +#else +pool_get(struct pool *pp, int flags) +#endif { - void *v; struct pool_item *pi; + struct pool_item_header *ph; + void *v; -again: - simple_lock(&pp->pr_lock); - if ((v = pp->pr_freelist) == NULL) { - if (flags & PR_MALLOCOK) - v = (void *)malloc(pp->pr_size, pp->pr_mtype, M_NOWAIT); +#ifdef DIAGNOSTIC + if (__predict_false(curproc == NULL && doing_shutdown == 0 && + (flags & PR_WAITOK) != 0)) + panic("pool_get: %s: must have NOWAIT", pp->pr_wchan); + +#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; + } - if (v == NULL) { - if ((flags & PR_WAITOK) == 0) + /* + * 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"); + } +#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; - simple_unlock(&pp->pr_lock); - tsleep((caddr_t)pp, PSWP, pp->pr_wchan, 0); - goto again; + /* 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; } - } else { - pi = v; - pp->pr_freelist = pi->pi_next; - pp->pr_freecount--; + + /* 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"); + } +#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. + */ } - simple_unlock(&pp->pr_lock); + + pr_leave(pp); + simple_unlock(&pp->pr_slock); return (v); } /* - * Return resource to the pool; must be called at splbio + * Internal version of pool_put(). Pool is already locked/entered. */ -void -pool_put(pp, v) - struct pool *pp; - void *v; +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 - simple_lock(&pp->pr_lock); - if ((pp->pr_flags & PR_WANTED) || pp->pr_freecount < pp->pr_hiwat) { - /* Return to pool */ - pi->pi_next = pp->pr_freelist; - pp->pr_freelist = pi; - pp->pr_freecount++; - if (pp->pr_flags & PR_WANTED) { - pp->pr_flags &= ~PR_WANTED; - wakeup((caddr_t)pp); + 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; } - } else { - /* Return to system */ - free(v, M_DEVBUF); + } +#endif + + TAILQ_INSERT_HEAD(&ph->ph_itemlist, pi, pi_list); + KDASSERT(ph->ph_nmissing != 0); + 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; + + KASSERT(((((vaddr_t)pi) + ioff) & (align - 1)) == 0); + + /* 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)) { /* - * Return any excess items allocated during periods of - * contention. + * Call the page back-end allocator for more memory. + * + * XXX: We never wait, so should we bother unlocking + * the pool descriptor? */ - while (pp->pr_freecount > pp->pr_hiwat) { - pi = pp->pr_freelist; - pp->pr_freelist = pi->pi_next; - pp->pr_freecount--; - free(pi, M_DEVBUF); + 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++; } - simple_unlock(&pp->pr_lock); + + 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); } /* - * Add N items to the pool + * Release all complete pages that have not been used recently. */ int -pool_prime(pp, n) +#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 n; + 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; + } - simple_lock(&pp->pr_lock); - pp->pr_hiwat += n; - while (n--) { - pi = malloc(pp->pr_size, pp->pr_mtype, M_NOWAIT); - if (pi == NULL) { - simple_unlock(&pp->pr_lock); - return (ENOMEM); + (*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); +} - pi->pi_next = pp->pr_freelist; - pp->pr_freelist = pi; - pp->pr_freecount++; +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; + } } - simple_unlock(&pp->pr_lock); - return (0); +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 */