/* $OpenBSD: subr_pool.c,v 1.90 2009/09/05 16:06:57 thib Exp $ */ /* $NetBSD: subr_pool.c,v 1.61 2001/09/26 07:14:56 chs 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. * * 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 <sys/param.h> #include <sys/systm.h> #include <sys/proc.h> #include <sys/errno.h> #include <sys/kernel.h> #include <sys/malloc.h> #include <sys/pool.h> #include <sys/syslog.h> #include <sys/sysctl.h> #include <uvm/uvm.h> /* * 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 one of three lists in the * pool structure: `pr_emptypages', `pr_fullpages' and `pr_partpages', * for empty, full and partially-full pages respectively. 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 */ struct pool phpool; struct pool_item_header { /* Page headers */ LIST_ENTRY(pool_item_header) ph_pagelist; /* pool page list */ TAILQ_HEAD(,pool_item) ph_itemlist; /* chunk list for this page */ RB_ENTRY(pool_item_header) ph_node; /* Off-page page headers */ int ph_nmissing; /* # of chunks in use */ caddr_t ph_page; /* this page's address */ caddr_t ph_colored; /* page's colored address */ int ph_pagesize; }; struct pool_item { #ifdef DIAGNOSTIC u_int32_t pi_magic; #endif /* Other entries use only this list entry */ TAILQ_ENTRY(pool_item) pi_list; }; #ifdef DEADBEEF1 #define PI_MAGIC DEADBEEF1 #else #define PI_MAGIC 0xdeafbeef #endif #define POOL_NEEDS_CATCHUP(pp) \ ((pp)->pr_nitems < (pp)->pr_minitems) /* * Every pool gets a unique serial number assigned to it. If this counter * wraps, we're screwed, but we shouldn't create so many pools anyway. */ unsigned int pool_serial; int pool_catchup(struct pool *); void pool_prime_page(struct pool *, caddr_t, struct pool_item_header *); void pool_update_curpage(struct pool *); void *pool_do_get(struct pool *, int); void pool_do_put(struct pool *, void *); void pr_rmpage(struct pool *, struct pool_item_header *, struct pool_pagelist *); int pool_chk_page(struct pool *, const char *, struct pool_item_header *); struct pool_item_header *pool_alloc_item_header(struct pool *, caddr_t , int); void *pool_allocator_alloc(struct pool *, int, int *); void pool_allocator_free(struct pool *, void *); /* * XXX - quick hack. For pools with large items we want to use a special * allocator. For now, instead of having the allocator figure out * the allocation size from the pool (which can be done trivially * with round_page(pr_itemsperpage * pr_size)) which would require * lots of changes everywhere, we just create allocators for each * size. We limit those to 128 pages. */ #define POOL_LARGE_MAXPAGES 128 struct pool_allocator pool_allocator_large[POOL_LARGE_MAXPAGES]; struct pool_allocator pool_allocator_large_ni[POOL_LARGE_MAXPAGES]; void *pool_large_alloc(struct pool *, int, int *); void pool_large_free(struct pool *, void *); void *pool_large_alloc_ni(struct pool *, int, int *); void pool_large_free_ni(struct pool *, void *); #ifdef DDB void pool_print_pagelist(struct pool_pagelist *, int (*)(const char *, ...)); void pool_print1(struct pool *, const char *, int (*)(const char *, ...)); #endif #define pool_sleep(pl) msleep(pl, &pl->pr_mtx, PSWP, pl->pr_wchan, 0) static __inline int phtree_compare(struct pool_item_header *a, struct pool_item_header *b) { long diff = (vaddr_t)a->ph_page - (vaddr_t)b->ph_page; if (diff < 0) return -(-diff >= a->ph_pagesize); else if (diff > 0) return (diff >= b->ph_pagesize); else return (0); } RB_PROTOTYPE(phtree, pool_item_header, ph_node, phtree_compare); RB_GENERATE(phtree, pool_item_header, ph_node, phtree_compare); /* * Return the pool page header based on page address. */ static __inline struct pool_item_header * pr_find_pagehead(struct pool *pp, void *v) { struct pool_item_header *ph, tmp; if ((pp->pr_roflags & PR_PHINPAGE) != 0) { caddr_t page; page = (caddr_t)((vaddr_t)v & pp->pr_alloc->pa_pagemask); return ((struct pool_item_header *)(page + pp->pr_phoffset)); } /* * The trick we're using in the tree compare function is to compare * two elements equal when they overlap. We want to return the * page header that belongs to the element just before this address. * We don't want this element to compare equal to the next element, * so the compare function takes the pagesize from the lower element. * If this header is the lower, its pagesize is zero, so it can't * overlap with the next header. But if the header we're looking for * is lower, we'll use its pagesize and it will overlap and return * equal. */ tmp.ph_page = v; tmp.ph_pagesize = 0; ph = RB_FIND(phtree, &pp->pr_phtree, &tmp); if (ph) { KASSERT(ph->ph_page <= (caddr_t)v); KASSERT(ph->ph_page + ph->ph_pagesize > (caddr_t)v); } return ph; } /* * Remove a page from the pool. */ void pr_rmpage(struct pool *pp, struct pool_item_header *ph, struct pool_pagelist *pq) { /* * 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). */ LIST_REMOVE(ph, ph_pagelist); if ((pp->pr_roflags & PR_PHINPAGE) == 0) RB_REMOVE(phtree, &pp->pr_phtree, ph); if (pq) { LIST_INSERT_HEAD(pq, ph, ph_pagelist); } else { pool_allocator_free(pp, ph->ph_page); if ((pp->pr_roflags & PR_PHINPAGE) == 0) pool_put(&phpool, ph); } pp->pr_npages--; pp->pr_npagefree++; pool_update_curpage(pp); } /* * 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; #ifdef MALLOC_DEBUG if ((flags & PR_DEBUG) && (ioff != 0 || align != 0)) flags &= ~PR_DEBUG; #endif /* * Check arguments and construct default values. */ if (palloc == NULL) { if (size > PAGE_SIZE) { int psize; /* * XXX - should take align into account as well. */ if (size == round_page(size)) psize = size / PAGE_SIZE; else psize = PAGE_SIZE / roundup(size % PAGE_SIZE, 1024); if (psize > POOL_LARGE_MAXPAGES) psize = POOL_LARGE_MAXPAGES; if (flags & PR_WAITOK) palloc = &pool_allocator_large_ni[psize-1]; else palloc = &pool_allocator_large[psize-1]; if (palloc->pa_pagesz == 0) { palloc->pa_pagesz = psize * PAGE_SIZE; if (flags & PR_WAITOK) { palloc->pa_alloc = pool_large_alloc_ni; palloc->pa_free = pool_large_free_ni; } else { palloc->pa_alloc = pool_large_alloc; palloc->pa_free = pool_large_free; } } } else { palloc = &pool_allocator_nointr; } } if (palloc->pa_pagesz == 0) { palloc->pa_pagesz = PAGE_SIZE; } if (palloc->pa_pagemask == 0) { palloc->pa_pagemask = ~(palloc->pa_pagesz - 1); palloc->pa_pageshift = ffs(palloc->pa_pagesz) - 1; } 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. */ LIST_INIT(&pp->pr_emptypages); LIST_INIT(&pp->pr_fullpages); LIST_INIT(&pp->pr_partpages); pp->pr_curpage = NULL; pp->pr_npages = 0; pp->pr_minitems = 0; pp->pr_minpages = 0; pp->pr_maxpages = 8; 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_serial = ++pool_serial; if (pool_serial == 0) panic("pool_init: too much uptime"); /* constructor, destructor, and arg */ pp->pr_ctor = NULL; pp->pr_dtor = NULL; pp->pr_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 into an RB tree, 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 && pp->pr_size < PAGE_SIZE) { /* 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; RB_INIT(&pp->pr_phtree); } /* * 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; pp->pr_ipl = -1; mtx_init(&pp->pr_mtx, IPL_NONE); if (phpool.pr_size == 0) { pool_init(&phpool, sizeof(struct pool_item_header), 0, 0, 0, "phpool", NULL); pool_setipl(&phpool, IPL_HIGH); } /* Insert this into the list of all pools. */ TAILQ_INSERT_HEAD(&pool_head, pp, pr_poollist); } void pool_setipl(struct pool *pp, int ipl) { pp->pr_ipl = ipl; mtx_init(&pp->pr_mtx, ipl); } /* * Decommission a pool resource. */ void pool_destroy(struct pool *pp) { struct pool_item_header *ph; #ifdef DIAGNOSTIC if (pp->pr_nout != 0) panic("pool_destroy: pool busy: still out: %u", pp->pr_nout); #endif /* Remove all pages */ while ((ph = LIST_FIRST(&pp->pr_emptypages)) != NULL) pr_rmpage(pp, ph, NULL); KASSERT(LIST_EMPTY(&pp->pr_fullpages)); KASSERT(LIST_EMPTY(&pp->pr_partpages)); /* Remove from global pool list */ TAILQ_REMOVE(&pool_head, pp, pr_poollist); } struct pool_item_header * pool_alloc_item_header(struct pool *pp, caddr_t storage, int flags) { struct pool_item_header *ph; if ((pp->pr_roflags & PR_PHINPAGE) != 0) ph = (struct pool_item_header *)(storage + pp->pr_phoffset); else { ph = pool_get(&phpool, flags); } return (ph); } /* * Grab an item from the pool; must be called at appropriate spl level */ void * pool_get(struct pool *pp, int flags) { void *v; #ifdef DIAGNOSTIC if ((flags & PR_WAITOK) != 0) splassert(IPL_NONE); #endif /* DIAGNOSTIC */ mtx_enter(&pp->pr_mtx); v = pool_do_get(pp, flags); mtx_leave(&pp->pr_mtx); if (v == NULL) return (v); if (pp->pr_ctor) { if (flags & PR_ZERO) panic("pool_get: PR_ZERO when ctor set"); if (pp->pr_ctor(pp->pr_arg, v, flags)) { mtx_enter(&pp->pr_mtx); pool_do_put(pp, v); mtx_leave(&pp->pr_mtx); v = NULL; } } else { if (flags & PR_ZERO) memset(v, 0, pp->pr_size); } if (v != NULL) pp->pr_nget++; return (v); } void * pool_do_get(struct pool *pp, int flags) { struct pool_item *pi; struct pool_item_header *ph; void *v; int slowdown = 0; #if defined(DIAGNOSTIC) && defined(POOL_DEBUG) int i, *ip; #endif #ifdef MALLOC_DEBUG if (pp->pr_roflags & PR_DEBUG) { void *addr; addr = NULL; debug_malloc(pp->pr_size, M_DEBUG, (flags & PR_WAITOK) ? M_WAITOK : M_NOWAIT, &addr); return (addr); } #endif 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)) panic("pool_do_get: %s: crossed hard limit", pp->pr_wchan); #endif if (__predict_false(pp->pr_nout == pp->pr_hardlimit)) { if ((flags & PR_WAITOK) && !(flags & PR_LIMITFAIL)) { /* * XXX: A warning isn't logged in this case. Should * it be? */ pp->pr_flags |= PR_WANTED; pool_sleep(pp); 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++; 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) { printf("pool_do_get: %s: curpage NULL, nitems %u\n", pp->pr_wchan, pp->pr_nitems); panic("pool_do_get: nitems inconsistent"); } #endif /* * Call the back-end page allocator for more memory. */ v = pool_allocator_alloc(pp, flags, &slowdown); if (__predict_true(v != NULL)) ph = pool_alloc_item_header(pp, v, flags); if (__predict_false(v == NULL || ph == NULL)) { if (v != NULL) pool_allocator_free(pp, v); if ((flags & PR_WAITOK) == 0) { pp->pr_nfail++; 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; pool_sleep(pp); goto startover; } /* We have more memory; add it to the pool */ pool_prime_page(pp, v, ph); pp->pr_npagealloc++; if (slowdown && (flags & PR_WAITOK)) { mtx_leave(&pp->pr_mtx); yield(); mtx_enter(&pp->pr_mtx); } /* Start the allocation process over. */ goto startover; } if (__predict_false((v = pi = TAILQ_FIRST(&ph->ph_itemlist)) == NULL)) { panic("pool_do_get: %s: page empty", pp->pr_wchan); } #ifdef DIAGNOSTIC if (__predict_false(pp->pr_nitems == 0)) { printf("pool_do_get: %s: items on itemlist, nitems %u\n", pp->pr_wchan, pp->pr_nitems); panic("pool_do_get: nitems inconsistent"); } #endif #ifdef DIAGNOSTIC if (__predict_false(pi->pi_magic != PI_MAGIC)) panic("pool_do_get(%s): free list modified: " "page %p; item addr %p; offset 0x%x=0x%x", pp->pr_wchan, ph->ph_page, pi, 0, pi->pi_magic); #ifdef POOL_DEBUG for (ip = (int *)pi, i = sizeof(*pi) / sizeof(int); i < pp->pr_size / sizeof(int); i++) { if (ip[i] != PI_MAGIC) { panic("pool_do_get(%s): free list modified: " "page %p; item addr %p; offset 0x%x=0x%x", pp->pr_wchan, ph->ph_page, pi, i * sizeof(int), ip[i]); } } #endif /* POOL_DEBUG */ #endif /* DIAGNOSTIC */ /* * 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_do_get: nidle inconsistent"); #endif pp->pr_nidle--; /* * This page was previously empty. Move it to the list of * partially-full pages. This page is already curpage. */ LIST_REMOVE(ph, ph_pagelist); LIST_INSERT_HEAD(&pp->pr_partpages, ph, ph_pagelist); } ph->ph_nmissing++; if (TAILQ_EMPTY(&ph->ph_itemlist)) { #ifdef DIAGNOSTIC if (__predict_false(ph->ph_nmissing != pp->pr_itemsperpage)) { panic("pool_do_get: %s: nmissing inconsistent", pp->pr_wchan); } #endif /* * This page is now full. Move it to the full list * and select a new current page. */ LIST_REMOVE(ph, ph_pagelist); LIST_INSERT_HEAD(&pp->pr_fullpages, ph, ph_pagelist); pool_update_curpage(pp); } /* * 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. */ } return (v); } /* * Return resource to the pool; must be called at appropriate spl level */ void pool_put(struct pool *pp, void *v) { if (pp->pr_dtor) pp->pr_dtor(pp->pr_arg, v); mtx_enter(&pp->pr_mtx); pool_do_put(pp, v); mtx_leave(&pp->pr_mtx); pp->pr_nput++; } /* * Internal version of pool_put(). */ void pool_do_put(struct pool *pp, void *v) { struct pool_item *pi = v; struct pool_item_header *ph; #if defined(DIAGNOSTIC) && defined(POOL_DEBUG) int i, *ip; #endif if (v == NULL) panic("pool_put of NULL"); #ifdef MALLOC_DEBUG if (pp->pr_roflags & PR_DEBUG) { debug_free(v, M_DEBUG); return; } #endif #ifdef DIAGNOSTIC if (pp->pr_ipl != -1) splassert(pp->pr_ipl); if (__predict_false(pp->pr_nout == 0)) { printf("pool %s: putting with none out\n", pp->pr_wchan); panic("pool_do_put"); } #endif if (__predict_false((ph = pr_find_pagehead(pp, v)) == NULL)) { panic("pool_do_put: %s: page header missing", pp->pr_wchan); } /* * Return to item list. */ #ifdef DIAGNOSTIC pi->pi_magic = PI_MAGIC; #ifdef POOL_DEBUG for (ip = (int *)pi, i = sizeof(*pi)/sizeof(int); i < pp->pr_size / sizeof(int); i++) ip[i] = PI_MAGIC; #endif /* POOL_DEBUG */ #endif /* DIAGNOSTIC */ TAILQ_INSERT_HEAD(&ph->ph_itemlist, pi, pi_list); ph->ph_nmissing--; 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(pp); return; } /* * If this page is now empty, 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) Otherwise, move the page to the empty page list. * * Either way, select a new current page (so we use a partially-full * page if one is available). */ if (ph->ph_nmissing == 0) { pp->pr_nidle++; if (pp->pr_nidle > pp->pr_maxpages) { pr_rmpage(pp, ph, NULL); } else { LIST_REMOVE(ph, ph_pagelist); LIST_INSERT_HEAD(&pp->pr_emptypages, ph, ph_pagelist); } pool_update_curpage(pp); } /* * If the page was previously completely full, move it to the * partially-full 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)) { LIST_REMOVE(ph, ph_pagelist); LIST_INSERT_HEAD(&pp->pr_partpages, ph, ph_pagelist); pp->pr_curpage = ph; } } /* * Add N items to the pool. */ int pool_prime(struct pool *pp, int n) { struct pool_item_header *ph; caddr_t cp; int newpages; int slowdown; mtx_enter(&pp->pr_mtx); newpages = roundup(n, pp->pr_itemsperpage) / pp->pr_itemsperpage; while (newpages-- > 0) { cp = pool_allocator_alloc(pp, PR_NOWAIT, &slowdown); if (__predict_true(cp != NULL)) ph = pool_alloc_item_header(pp, cp, PR_NOWAIT); 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 */ mtx_leave(&pp->pr_mtx); return (0); } /* * Add a page worth of items to the pool. * * Note, we must be called with the pool descriptor LOCKED. */ 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; #if defined(DIAGNOSTIC) && defined(POOL_DEBUG) int i, *ip; #endif /* * Insert page header. */ LIST_INSERT_HEAD(&pp->pr_emptypages, ph, ph_pagelist); TAILQ_INIT(&ph->ph_itemlist); ph->ph_page = storage; ph->ph_pagesize = pp->pr_alloc->pa_pagesz; ph->ph_nmissing = 0; if ((pp->pr_roflags & PR_PHINPAGE) == 0) RB_INSERT(phtree, &pp->pr_phtree, ph); 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)); ph->ph_colored = cp; /* * 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; #ifdef POOL_DEBUG for (ip = (int *)pi, i = sizeof(*pi)/sizeof(int); i < pp->pr_size / sizeof(int); i++) ip[i] = PI_MAGIC; #endif /* POOL_DEBUG */ #endif /* DIAGNOSTIC */ 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 pr_nitems with the low water mark. * * Note we never wait for memory here, we let the caller decide what to do. */ int pool_catchup(struct pool *pp) { struct pool_item_header *ph; caddr_t cp; int error = 0; int slowdown; while (POOL_NEEDS_CATCHUP(pp)) { /* * Call the page back-end allocator for more memory. */ cp = pool_allocator_alloc(pp, PR_NOWAIT, &slowdown); if (__predict_true(cp != NULL)) ph = pool_alloc_item_header(pp, cp, PR_NOWAIT); 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_update_curpage(struct pool *pp) { pp->pr_curpage = LIST_FIRST(&pp->pr_partpages); if (pp->pr_curpage == NULL) { pp->pr_curpage = LIST_FIRST(&pp->pr_emptypages); } } void pool_setlowat(struct pool *pp, int n) { pp->pr_minitems = n; pp->pr_minpages = (n == 0) ? 0 : roundup(n, pp->pr_itemsperpage) / pp->pr_itemsperpage; mtx_enter(&pp->pr_mtx); /* 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. */ } mtx_leave(&pp->pr_mtx); } void pool_sethiwat(struct pool *pp, int n) { pp->pr_maxpages = (n == 0) ? 0 : roundup(n, pp->pr_itemsperpage) / pp->pr_itemsperpage; } int pool_sethardlimit(struct pool *pp, u_int n, const char *warnmsg, int ratecap) { int error = 0; if (n < pp->pr_nout) { error = EINVAL; goto done; } pp->pr_hardlimit = n; pp->pr_hardlimit_warning = warnmsg; 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(). */ pp->pr_maxpages = (n == 0 || n == UINT_MAX) ? n : roundup(n, pp->pr_itemsperpage) / pp->pr_itemsperpage; done: return (error); } void pool_set_ctordtor(struct pool *pp, int (*ctor)(void *, void *, int), void (*dtor)(void *, void *), void *arg) { pp->pr_ctor = ctor; pp->pr_dtor = dtor; pp->pr_arg = arg; } /* * Release all complete pages that have not been used recently. * * Returns non-zero if any pages have been reclaimed. */ int pool_reclaim(struct pool *pp) { struct pool_item_header *ph, *phnext; struct pool_pagelist pq; LIST_INIT(&pq); mtx_enter(&pp->pr_mtx); for (ph = LIST_FIRST(&pp->pr_emptypages); ph != NULL; ph = phnext) { phnext = LIST_NEXT(ph, ph_pagelist); /* Check our minimum page claim */ if (pp->pr_npages <= pp->pr_minpages) break; KASSERT(ph->ph_nmissing == 0); /* * 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); } mtx_leave(&pp->pr_mtx); if (LIST_EMPTY(&pq)) return (0); while ((ph = LIST_FIRST(&pq)) != NULL) { LIST_REMOVE(ph, ph_pagelist); pool_allocator_free(pp, ph->ph_page); if (pp->pr_roflags & PR_PHINPAGE) continue; pool_put(&phpool, ph); } return (1); } #ifdef DDB #include <machine/db_machdep.h> #include <ddb/db_interface.h> #include <ddb/db_output.h> /* * Diagnostic helpers. */ void pool_printit(struct pool *pp, const char *modif, int (*pr)(const char *, ...)) { pool_print1(pp, modif, pr); } void pool_print_pagelist(struct pool_pagelist *pl, int (*pr)(const char *, ...)) { struct pool_item_header *ph; #ifdef DIAGNOSTIC struct pool_item *pi; #endif LIST_FOREACH(ph, pl, ph_pagelist) { (*pr)("\t\tpage %p, nmissing %d\n", ph->ph_page, ph->ph_nmissing); #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 } } void pool_print1(struct pool *pp, const char *modif, int (*pr)(const char *, ...)) { struct pool_item_header *ph; int print_pagelist = 0; char c; while ((c = *modif++) != '\0') { if (c == 'p') print_pagelist = 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) return; if ((ph = LIST_FIRST(&pp->pr_emptypages)) != NULL) (*pr)("\n\tempty page list:\n"); pool_print_pagelist(&pp->pr_emptypages, pr); if ((ph = LIST_FIRST(&pp->pr_fullpages)) != NULL) (*pr)("\n\tfull page list:\n"); pool_print_pagelist(&pp->pr_fullpages, pr); if ((ph = LIST_FIRST(&pp->pr_partpages)) != NULL) (*pr)("\n\tpartial-page list:\n"); pool_print_pagelist(&pp->pr_partpages, pr); if (pp->pr_curpage == NULL) (*pr)("\tno current page\n"); else (*pr)("\tcurpage %p\n", pp->pr_curpage->ph_page); } void db_show_all_pools(db_expr_t expr, int haddr, db_expr_t count, char *modif) { struct pool *pp; char maxp[16]; int ovflw; char mode; mode = modif[0]; if (mode != '\0' && mode != 'a') { db_printf("usage: show all pools [/a]\n"); return; } if (mode == '\0') db_printf("%-10s%4s%9s%5s%9s%6s%6s%6s%6s%6s%6s%5s\n", "Name", "Size", "Requests", "Fail", "Releases", "Pgreq", "Pgrel", "Npage", "Hiwat", "Minpg", "Maxpg", "Idle"); else db_printf("%-10s %18s %18s\n", "Name", "Address", "Allocator"); TAILQ_FOREACH(pp, &pool_head, pr_poollist) { if (mode == 'a') { db_printf("%-10s %18p %18p\n", pp->pr_wchan, pp, pp->pr_alloc); continue; } if (!pp->pr_nget) continue; if (pp->pr_maxpages == UINT_MAX) snprintf(maxp, sizeof maxp, "inf"); else snprintf(maxp, sizeof maxp, "%u", pp->pr_maxpages); #define PRWORD(ovflw, fmt, width, fixed, val) do { \ (ovflw) += db_printf((fmt), \ (width) - (fixed) - (ovflw) > 0 ? \ (width) - (fixed) - (ovflw) : 0, \ (val)) - (width); \ if ((ovflw) < 0) \ (ovflw) = 0; \ } while (/* CONSTCOND */0) ovflw = 0; PRWORD(ovflw, "%-*s", 10, 0, pp->pr_wchan); PRWORD(ovflw, " %*u", 4, 1, pp->pr_size); PRWORD(ovflw, " %*lu", 9, 1, pp->pr_nget); PRWORD(ovflw, " %*lu", 5, 1, pp->pr_nfail); PRWORD(ovflw, " %*lu", 9, 1, pp->pr_nput); PRWORD(ovflw, " %*lu", 6, 1, pp->pr_npagealloc); PRWORD(ovflw, " %*lu", 6, 1, pp->pr_npagefree); PRWORD(ovflw, " %*d", 6, 1, pp->pr_npages); PRWORD(ovflw, " %*d", 6, 1, pp->pr_hiwat); PRWORD(ovflw, " %*d", 6, 1, pp->pr_minpages); PRWORD(ovflw, " %*s", 6, 1, maxp); PRWORD(ovflw, " %*lu\n", 5, 1, pp->pr_nidle); pool_chk(pp, pp->pr_wchan); } } int pool_chk_page(struct pool *pp, const char *label, struct pool_item_header *ph) { struct pool_item *pi; caddr_t page; int n; #if defined(DIAGNOSTIC) && defined(POOL_DEBUG) int i, *ip; #endif 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); return 1; } 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: " "page %p; item ordinal %d; addr %p " "(p %p); offset 0x%x=0x%x\n", pp->pr_wchan, ph->ph_page, n, pi, page, 0, pi->pi_magic); } #ifdef POOL_DEBUG for (ip = (int *)pi, i = sizeof(*pi) / sizeof(int); i < pp->pr_size / sizeof(int); i++) { if (ip[i] != PI_MAGIC) { printf("pool(%s): free list modified: " "page %p; item ordinal %d; addr %p " "(p %p); offset 0x%x=0x%x\n", pp->pr_wchan, ph->ph_page, n, pi, page, i * sizeof(int), ip[i]); } } #endif /* POOL_DEBUG */ #endif /* DIAGNOSTIC */ 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); return 1; } return 0; } int pool_chk(struct pool *pp, const char *label) { struct pool_item_header *ph; int r = 0; LIST_FOREACH(ph, &pp->pr_emptypages, ph_pagelist) r += pool_chk_page(pp, label, ph); LIST_FOREACH(ph, &pp->pr_fullpages, ph_pagelist) r += pool_chk_page(pp, label, ph); LIST_FOREACH(ph, &pp->pr_partpages, ph_pagelist) r += pool_chk_page(pp, label, ph); return (r); } void pool_walk(struct pool *pp, int full, int (*pr)(const char *, ...), void (*func)(void *, int, int (*)(const char *, ...))) { struct pool_item_header *ph; struct pool_item *pi; caddr_t cp; int n; LIST_FOREACH(ph, &pp->pr_fullpages, ph_pagelist) { cp = ph->ph_colored; n = ph->ph_nmissing; while (n--) { func(cp, full, pr); cp += pp->pr_size; } } LIST_FOREACH(ph, &pp->pr_partpages, ph_pagelist) { cp = ph->ph_colored; n = ph->ph_nmissing; do { TAILQ_FOREACH(pi, &ph->ph_itemlist, pi_list) { if (cp == (caddr_t)pi) break; } if (cp != (caddr_t)pi) { func(cp, full, pr); n--; } cp += pp->pr_size; } while (n > 0); } } #endif /* * We have three different sysctls. * kern.pool.npools - the number of pools. * kern.pool.pool.<pool#> - the pool struct for the pool#. * kern.pool.name.<pool#> - the name for pool#. */ int sysctl_dopool(int *name, u_int namelen, char *where, size_t *sizep) { struct pool *pp, *foundpool = NULL; size_t buflen = where != NULL ? *sizep : 0; int npools = 0, s; unsigned int lookfor; size_t len; switch (*name) { case KERN_POOL_NPOOLS: if (namelen != 1 || buflen != sizeof(int)) return (EINVAL); lookfor = 0; break; case KERN_POOL_NAME: if (namelen != 2 || buflen < 1) return (EINVAL); lookfor = name[1]; break; case KERN_POOL_POOL: if (namelen != 2 || buflen != sizeof(struct pool)) return (EINVAL); lookfor = name[1]; break; default: return (EINVAL); } s = splvm(); TAILQ_FOREACH(pp, &pool_head, pr_poollist) { npools++; if (lookfor == pp->pr_serial) { foundpool = pp; break; } } splx(s); if (*name != KERN_POOL_NPOOLS && foundpool == NULL) return (ENOENT); switch (*name) { case KERN_POOL_NPOOLS: return copyout(&npools, where, buflen); case KERN_POOL_NAME: len = strlen(foundpool->pr_wchan) + 1; if (*sizep < len) return (ENOMEM); *sizep = len; return copyout(foundpool->pr_wchan, where, len); case KERN_POOL_POOL: return copyout(foundpool, where, buflen); } /* NOTREACHED */ return (0); /* XXX - Stupid gcc */ } /* * Pool backend allocators. * * Each pool has a backend allocator that handles allocation, deallocation */ void *pool_page_alloc(struct pool *, int, int *); void pool_page_free(struct pool *, void *); /* * safe for interrupts, name preserved for compat this is the default * allocator */ struct pool_allocator pool_allocator_nointr = { pool_page_alloc, pool_page_free, 0, }; /* * XXX - 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, then 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 addresses, so we have to fake. The caller sleeps on * the pool (so that we 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 wakeup all * sleeping pools belonging to this allocator. (XXX - thundering herd). * We also wake up the allocator in case someone without a pool (malloc) * is sleeping waiting for this allocator. */ void * pool_allocator_alloc(struct pool *pp, int flags, int *slowdown) { boolean_t waitok = (flags & PR_WAITOK) ? TRUE : FALSE; void *v; if (waitok) mtx_leave(&pp->pr_mtx); v = pp->pr_alloc->pa_alloc(pp, flags, slowdown); if (waitok) mtx_enter(&pp->pr_mtx); return (v); } void pool_allocator_free(struct pool *pp, void *v) { struct pool_allocator *pa = pp->pr_alloc; (*pa->pa_free)(pp, v); } void * pool_page_alloc(struct pool *pp, int flags, int *slowdown) { boolean_t waitok = (flags & PR_WAITOK) ? TRUE : FALSE; return (uvm_km_getpage(waitok, slowdown)); } void pool_page_free(struct pool *pp, void *v) { uvm_km_putpage(v); } void * pool_large_alloc(struct pool *pp, int flags, int *slowdown) { int kfl = (flags & PR_WAITOK) ? 0 : UVM_KMF_NOWAIT; vaddr_t va; int s; s = splvm(); va = uvm_km_kmemalloc(kmem_map, NULL, pp->pr_alloc->pa_pagesz, kfl); splx(s); return ((void *)va); } void pool_large_free(struct pool *pp, void *v) { int s; s = splvm(); uvm_km_free(kmem_map, (vaddr_t)v, pp->pr_alloc->pa_pagesz); splx(s); } void * pool_large_alloc_ni(struct pool *pp, int flags, int *slowdown) { int kfl = (flags & PR_WAITOK) ? 0 : UVM_KMF_NOWAIT; return ((void *)uvm_km_kmemalloc(kernel_map, uvm.kernel_object, pp->pr_alloc->pa_pagesz, kfl)); } void pool_large_free_ni(struct pool *pp, void *v) { uvm_km_free(kernel_map, (vaddr_t)v, pp->pr_alloc->pa_pagesz); }