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-rw-r--r--src/pool.c1108
1 files changed, 1108 insertions, 0 deletions
diff --git a/src/pool.c b/src/pool.c
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--- /dev/null
+++ b/src/pool.c
@@ -0,0 +1,1108 @@
+/*
+ * Memory management functions.
+ *
+ * Copyright 2000-2007 Willy Tarreau <w@1wt.eu>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <sys/mman.h>
+#include <errno.h>
+
+#include <haproxy/activity.h>
+#include <haproxy/api.h>
+#include <haproxy/applet-t.h>
+#include <haproxy/cfgparse.h>
+#include <haproxy/channel.h>
+#include <haproxy/cli.h>
+#include <haproxy/errors.h>
+#include <haproxy/global.h>
+#include <haproxy/list.h>
+#include <haproxy/pool.h>
+#include <haproxy/sc_strm.h>
+#include <haproxy/stats-t.h>
+#include <haproxy/stconn.h>
+#include <haproxy/thread.h>
+#include <haproxy/tools.h>
+
+
+/* These ones are initialized per-thread on startup by init_pools() */
+THREAD_LOCAL size_t pool_cache_bytes = 0; /* total cache size */
+THREAD_LOCAL size_t pool_cache_count = 0; /* #cache objects */
+
+static struct list pools __read_mostly = LIST_HEAD_INIT(pools);
+int mem_poison_byte __read_mostly = 'P';
+uint pool_debugging __read_mostly = /* set of POOL_DBG_* flags */
+#ifdef DEBUG_FAIL_ALLOC
+ POOL_DBG_FAIL_ALLOC |
+#endif
+#ifdef DEBUG_DONT_SHARE_POOLS
+ POOL_DBG_DONT_MERGE |
+#endif
+#ifdef DEBUG_POOL_INTEGRITY
+ POOL_DBG_COLD_FIRST |
+#endif
+#ifdef DEBUG_POOL_INTEGRITY
+ POOL_DBG_INTEGRITY |
+#endif
+#ifdef CONFIG_HAP_NO_GLOBAL_POOLS
+ POOL_DBG_NO_GLOBAL |
+#endif
+#ifndef CONFIG_HAP_POOLS
+ POOL_DBG_NO_CACHE |
+#endif
+#if defined(DEBUG_POOL_TRACING)
+ POOL_DBG_CALLER |
+#endif
+#if defined(DEBUG_MEMORY_POOLS)
+ POOL_DBG_TAG |
+#endif
+ 0;
+
+static const struct {
+ uint flg;
+ const char *set;
+ const char *clr;
+ const char *hlp;
+} dbg_options[] = {
+ /* flg, set, clr, hlp */
+ { POOL_DBG_FAIL_ALLOC, "fail", "no-fail", "randomly fail allocations" },
+ { POOL_DBG_DONT_MERGE, "no-merge", "merge", "disable merging of similar pools" },
+ { POOL_DBG_COLD_FIRST, "cold-first", "hot-first", "pick cold objects first" },
+ { POOL_DBG_INTEGRITY, "integrity", "no-integrity", "enable cache integrity checks" },
+ { POOL_DBG_NO_GLOBAL, "no-global", "global", "disable global shared cache" },
+ { POOL_DBG_NO_CACHE, "no-cache", "cache", "disable thread-local cache" },
+ { POOL_DBG_CALLER, "caller", "no-caller", "save caller information in cache" },
+ { POOL_DBG_TAG, "tag", "no-tag", "add tag at end of allocated objects" },
+ { POOL_DBG_POISON, "poison", "no-poison", "poison newly allocated objects" },
+ { 0 /* end */ }
+};
+
+static int mem_fail_rate __read_mostly = 0;
+static int using_default_allocator __read_mostly = 1;
+static int disable_trim __read_mostly = 0;
+static int(*my_mallctl)(const char *, void *, size_t *, void *, size_t) = NULL;
+
+/* ask the allocator to trim memory pools.
+ * This must run under thread isolation so that competing threads trying to
+ * allocate or release memory do not prevent the allocator from completing
+ * its job. We just have to be careful as callers might already be isolated
+ * themselves.
+ */
+static void trim_all_pools(void)
+{
+ int isolated = thread_isolated();
+
+ if (disable_trim)
+ return;
+
+ if (!isolated)
+ thread_isolate();
+
+ if (my_mallctl) {
+ unsigned int i, narenas = 0;
+ size_t len = sizeof(narenas);
+
+ if (my_mallctl("arenas.narenas", &narenas, &len, NULL, 0) == 0) {
+ for (i = 0; i < narenas; i ++) {
+ char mib[32] = {0};
+ snprintf(mib, sizeof(mib), "arena.%u.purge", i);
+ (void)my_mallctl(mib, NULL, NULL, NULL, 0);
+ }
+ }
+ } else {
+#if defined(HA_HAVE_MALLOC_TRIM)
+ if (using_default_allocator)
+ malloc_trim(0);
+#elif defined(HA_HAVE_MALLOC_ZONE)
+ if (using_default_allocator) {
+ vm_address_t *zones;
+ unsigned int i, nzones;
+
+ if (malloc_get_all_zones(0, NULL, &zones, &nzones) == KERN_SUCCESS) {
+ for (i = 0; i < nzones; i ++) {
+ malloc_zone_t *zone = (malloc_zone_t *)zones[i];
+
+ /* we cannot purge anonymous zones */
+ if (zone->zone_name)
+ malloc_zone_pressure_relief(zone, 0);
+ }
+ }
+ }
+#endif
+ }
+
+ if (!isolated)
+ thread_release();
+}
+
+/* check if we're using the same allocator as the one that provides
+ * malloc_trim() and mallinfo(). The principle is that on glibc, both
+ * malloc_trim() and mallinfo() are provided, and using mallinfo() we
+ * can check if malloc() is performed through glibc or any other one
+ * the executable was linked against (e.g. jemalloc). Prior to this we
+ * have to check whether we're running on jemalloc by verifying if the
+ * mallctl() function is provided. Its pointer will be used later.
+ */
+static void detect_allocator(void)
+{
+#if defined(__ELF__)
+ extern int mallctl(const char *, void *, size_t *, void *, size_t) __attribute__((weak));
+
+ my_mallctl = mallctl;
+#endif
+
+ if (!my_mallctl) {
+ my_mallctl = get_sym_curr_addr("mallctl");
+ using_default_allocator = (my_mallctl == NULL);
+ }
+
+ if (!my_mallctl) {
+#if defined(HA_HAVE_MALLOC_TRIM)
+#ifdef HA_HAVE_MALLINFO2
+ struct mallinfo2 mi1, mi2;
+#else
+ struct mallinfo mi1, mi2;
+#endif
+ void *ptr;
+
+#ifdef HA_HAVE_MALLINFO2
+ mi1 = mallinfo2();
+#else
+ mi1 = mallinfo();
+#endif
+ ptr = DISGUISE(malloc(1));
+#ifdef HA_HAVE_MALLINFO2
+ mi2 = mallinfo2();
+#else
+ mi2 = mallinfo();
+#endif
+ free(DISGUISE(ptr));
+
+ using_default_allocator = !!memcmp(&mi1, &mi2, sizeof(mi1));
+#elif defined(HA_HAVE_MALLOC_ZONE)
+ using_default_allocator = (malloc_default_zone() != NULL);
+#endif
+ }
+}
+
+static int is_trim_enabled(void)
+{
+ return using_default_allocator;
+}
+
+static int mem_should_fail(const struct pool_head *pool)
+{
+ int ret = 0;
+
+ if (mem_fail_rate > 0 && !(global.mode & MODE_STARTING)) {
+ if (mem_fail_rate > statistical_prng_range(100))
+ ret = 1;
+ else
+ ret = 0;
+ }
+ return ret;
+}
+
+/* Try to find an existing shared pool with the same characteristics and
+ * returns it, otherwise creates this one. NULL is returned if no memory
+ * is available for a new creation. Two flags are supported :
+ * - MEM_F_SHARED to indicate that the pool may be shared with other users
+ * - MEM_F_EXACT to indicate that the size must not be rounded up
+ */
+struct pool_head *create_pool(char *name, unsigned int size, unsigned int flags)
+{
+ unsigned int extra_mark, extra_caller, extra;
+ struct pool_head *pool;
+ struct pool_head *entry;
+ struct list *start;
+ unsigned int align;
+ int thr __maybe_unused;
+
+ /* We need to store a (void *) at the end of the chunks. Since we know
+ * that the malloc() function will never return such a small size,
+ * let's round the size up to something slightly bigger, in order to
+ * ease merging of entries. Note that the rounding is a power of two.
+ * This extra (void *) is not accounted for in the size computation
+ * so that the visible parts outside are not affected.
+ *
+ * Note: for the LRU cache, we need to store 2 doubly-linked lists.
+ */
+
+ extra_mark = (pool_debugging & POOL_DBG_TAG) ? POOL_EXTRA_MARK : 0;
+ extra_caller = (pool_debugging & POOL_DBG_CALLER) ? POOL_EXTRA_CALLER : 0;
+ extra = extra_mark + extra_caller;
+
+ if (!(flags & MEM_F_EXACT)) {
+ align = 4 * sizeof(void *); // 2 lists = 4 pointers min
+ size = ((size + extra + align - 1) & -align) - extra;
+ }
+
+ if (!(pool_debugging & POOL_DBG_NO_CACHE)) {
+ /* we'll store two lists there, we need the room for this. This is
+ * guaranteed by the test above, except if MEM_F_EXACT is set, or if
+ * the only EXTRA part is in fact the one that's stored in the cache
+ * in addition to the pci struct.
+ */
+ if (size + extra - extra_caller < sizeof(struct pool_cache_item))
+ size = sizeof(struct pool_cache_item) + extra_caller - extra;
+ }
+
+ /* TODO: thread: we do not lock pool list for now because all pools are
+ * created during HAProxy startup (so before threads creation) */
+ start = &pools;
+ pool = NULL;
+
+ list_for_each_entry(entry, &pools, list) {
+ if (entry->size == size) {
+ /* either we can share this place and we take it, or
+ * we look for a shareable one or for the next position
+ * before which we will insert a new one.
+ */
+ if ((flags & entry->flags & MEM_F_SHARED) &&
+ (!(pool_debugging & POOL_DBG_DONT_MERGE) ||
+ strcmp(name, entry->name) == 0)) {
+ /* we can share this one */
+ pool = entry;
+ DPRINTF(stderr, "Sharing %s with %s\n", name, pool->name);
+ break;
+ }
+ }
+ else if (entry->size > size) {
+ /* insert before this one */
+ start = &entry->list;
+ break;
+ }
+ }
+
+ if (!pool) {
+ void *pool_addr;
+
+ pool_addr = calloc(1, sizeof(*pool) + __alignof__(*pool));
+ if (!pool_addr)
+ return NULL;
+
+ /* always provide an aligned pool */
+ pool = (struct pool_head*)((((size_t)pool_addr) + __alignof__(*pool)) & -(size_t)__alignof__(*pool));
+ pool->base_addr = pool_addr; // keep it, it's the address to free later
+
+ if (name)
+ strlcpy2(pool->name, name, sizeof(pool->name));
+ pool->alloc_sz = size + extra;
+ pool->size = size;
+ pool->flags = flags;
+ LIST_APPEND(start, &pool->list);
+
+ if (!(pool_debugging & POOL_DBG_NO_CACHE)) {
+ /* update per-thread pool cache if necessary */
+ for (thr = 0; thr < MAX_THREADS; thr++) {
+ LIST_INIT(&pool->cache[thr].list);
+ pool->cache[thr].tid = thr;
+ pool->cache[thr].pool = pool;
+ }
+ }
+ }
+ pool->users++;
+ return pool;
+}
+
+/* Tries to allocate an object for the pool <pool> using the system's allocator
+ * and directly returns it. The pool's allocated counter is checked and updated,
+ * but no other checks are performed.
+ */
+void *pool_get_from_os(struct pool_head *pool)
+{
+ if (!pool->limit || pool->allocated < pool->limit) {
+ void *ptr = pool_alloc_area(pool->alloc_sz);
+ if (ptr) {
+ _HA_ATOMIC_INC(&pool->allocated);
+ return ptr;
+ }
+ _HA_ATOMIC_INC(&pool->failed);
+ }
+ activity[tid].pool_fail++;
+ return NULL;
+
+}
+
+/* Releases a pool item back to the operating system and atomically updates
+ * the allocation counter.
+ */
+void pool_put_to_os(struct pool_head *pool, void *ptr)
+{
+#ifdef DEBUG_UAF
+ /* This object will be released for real in order to detect a use after
+ * free. We also force a write to the area to ensure we crash on double
+ * free or free of a const area.
+ */
+ *(uint32_t *)ptr = 0xDEADADD4;
+#endif /* DEBUG_UAF */
+
+ pool_free_area(ptr, pool->alloc_sz);
+ _HA_ATOMIC_DEC(&pool->allocated);
+}
+
+/* Tries to allocate an object for the pool <pool> using the system's allocator
+ * and directly returns it. The pool's counters are updated but the object is
+ * never cached, so this is usable with and without local or shared caches.
+ */
+void *pool_alloc_nocache(struct pool_head *pool)
+{
+ void *ptr = NULL;
+
+ ptr = pool_get_from_os(pool);
+ if (!ptr)
+ return NULL;
+
+ swrate_add_scaled(&pool->needed_avg, POOL_AVG_SAMPLES, pool->used, POOL_AVG_SAMPLES/4);
+ _HA_ATOMIC_INC(&pool->used);
+
+ /* keep track of where the element was allocated from */
+ POOL_DEBUG_SET_MARK(pool, ptr);
+ POOL_DEBUG_TRACE_CALLER(pool, (struct pool_cache_item *)ptr, NULL);
+ return ptr;
+}
+
+/* Release a pool item back to the OS and keeps the pool's counters up to date.
+ * This is always defined even when pools are not enabled (their usage stats
+ * are maintained).
+ */
+void pool_free_nocache(struct pool_head *pool, void *ptr)
+{
+ _HA_ATOMIC_DEC(&pool->used);
+ swrate_add(&pool->needed_avg, POOL_AVG_SAMPLES, pool->used);
+ pool_put_to_os(pool, ptr);
+}
+
+
+/* Updates <pch>'s fill_pattern and fills the free area after <item> with it,
+ * up to <size> bytes. The item part is left untouched.
+ */
+void pool_fill_pattern(struct pool_cache_head *pch, struct pool_cache_item *item, uint size)
+{
+ ulong *ptr = (ulong *)item;
+ uint ofs;
+ ulong u;
+
+ if (size <= sizeof(*item))
+ return;
+
+ /* Upgrade the fill_pattern to change about half of the bits
+ * (to be sure to catch static flag corruption), and apply it.
+ */
+ u = pch->fill_pattern += ~0UL / 3; // 0x55...55
+ ofs = sizeof(*item) / sizeof(*ptr);
+ while (ofs < size / sizeof(*ptr))
+ ptr[ofs++] = u;
+}
+
+/* check for a pool_cache_item integrity after extracting it from the cache. It
+ * must have been previously initialized using pool_fill_pattern(). If any
+ * corruption is detected, the function provokes an immediate crash.
+ */
+void pool_check_pattern(struct pool_cache_head *pch, struct pool_cache_item *item, uint size)
+{
+ const ulong *ptr = (const ulong *)item;
+ uint ofs;
+ ulong u;
+
+ if (size <= sizeof(*item))
+ return;
+
+ /* let's check that all words past *item are equal */
+ ofs = sizeof(*item) / sizeof(*ptr);
+ u = ptr[ofs++];
+ while (ofs < size / sizeof(*ptr)) {
+ if (unlikely(ptr[ofs] != u))
+ ABORT_NOW();
+ ofs++;
+ }
+}
+
+/* removes up to <count> items from the end of the local pool cache <ph> for
+ * pool <pool>. The shared pool is refilled with these objects in the limit
+ * of the number of acceptable objects, and the rest will be released to the
+ * OS. It is not a problem is <count> is larger than the number of objects in
+ * the local cache. The counters are automatically updated. Must not be used
+ * with pools disabled.
+ */
+static void pool_evict_last_items(struct pool_head *pool, struct pool_cache_head *ph, uint count)
+{
+ struct pool_cache_item *item;
+ struct pool_item *pi, *head = NULL;
+ uint released = 0;
+ uint cluster = 0;
+ uint to_free_max;
+
+ BUG_ON(pool_debugging & POOL_DBG_NO_CACHE);
+
+ /* Note: this will be zero when global pools are disabled */
+ to_free_max = pool_releasable(pool);
+
+ while (released < count && !LIST_ISEMPTY(&ph->list)) {
+ item = LIST_PREV(&ph->list, typeof(item), by_pool);
+ BUG_ON(&item->by_pool == &ph->list);
+ if (unlikely(pool_debugging & POOL_DBG_INTEGRITY))
+ pool_check_pattern(ph, item, pool->size);
+ LIST_DELETE(&item->by_pool);
+ LIST_DELETE(&item->by_lru);
+
+ if (to_free_max > released || cluster) {
+ /* will never match when global pools are disabled */
+ pi = (struct pool_item *)item;
+ pi->next = NULL;
+ pi->down = head;
+ head = pi;
+ cluster++;
+ if (cluster >= CONFIG_HAP_POOL_CLUSTER_SIZE) {
+ /* enough to make a cluster */
+ pool_put_to_shared_cache(pool, head, cluster);
+ cluster = 0;
+ head = NULL;
+ }
+ } else
+ pool_free_nocache(pool, item);
+
+ released++;
+ }
+
+ /* incomplete cluster left */
+ if (cluster)
+ pool_put_to_shared_cache(pool, head, cluster);
+
+ ph->count -= released;
+ pool_cache_count -= released;
+ pool_cache_bytes -= released * pool->size;
+}
+
+/* Evicts some of the oldest objects from one local cache, until its number of
+ * objects is no more than 16+1/8 of the total number of locally cached objects
+ * or the total size of the local cache is no more than 75% of its maximum (i.e.
+ * we don't want a single cache to use all the cache for itself). For this, the
+ * list is scanned in reverse. If <full> is non-null, all objects are evicted.
+ * Must not be used when pools are disabled.
+ */
+void pool_evict_from_local_cache(struct pool_head *pool, int full)
+{
+ struct pool_cache_head *ph = &pool->cache[tid];
+
+ BUG_ON(pool_debugging & POOL_DBG_NO_CACHE);
+
+ while ((ph->count && full) ||
+ (ph->count >= CONFIG_HAP_POOL_CLUSTER_SIZE &&
+ ph->count >= 16 + pool_cache_count / 8 &&
+ pool_cache_bytes > CONFIG_HAP_POOL_CACHE_SIZE * 3 / 4)) {
+ pool_evict_last_items(pool, ph, CONFIG_HAP_POOL_CLUSTER_SIZE);
+ }
+}
+
+/* Evicts some of the oldest objects from the local cache, pushing them to the
+ * global pool. Must not be used when pools are disabled.
+ */
+void pool_evict_from_local_caches()
+{
+ struct pool_cache_item *item;
+ struct pool_cache_head *ph;
+ struct pool_head *pool;
+
+ BUG_ON(pool_debugging & POOL_DBG_NO_CACHE);
+
+ do {
+ item = LIST_PREV(&th_ctx->pool_lru_head, struct pool_cache_item *, by_lru);
+ BUG_ON(&item->by_lru == &th_ctx->pool_lru_head);
+ /* note: by definition we remove oldest objects so they also are the
+ * oldest in their own pools, thus their next is the pool's head.
+ */
+ ph = LIST_NEXT(&item->by_pool, struct pool_cache_head *, list);
+ BUG_ON(ph->tid != tid);
+
+ pool = container_of(ph - tid, struct pool_head, cache);
+ BUG_ON(pool != ph->pool);
+
+ pool_evict_last_items(pool, ph, CONFIG_HAP_POOL_CLUSTER_SIZE);
+ } while (pool_cache_bytes > CONFIG_HAP_POOL_CACHE_SIZE * 7 / 8);
+}
+
+/* Frees an object to the local cache, possibly pushing oldest objects to the
+ * shared cache, which itself may decide to release some of them to the OS.
+ * While it is unspecified what the object becomes past this point, it is
+ * guaranteed to be released from the users' perpective. A caller address may
+ * be passed and stored into the area when DEBUG_POOL_TRACING is set. Must not
+ * be used with pools disabled.
+ */
+void pool_put_to_cache(struct pool_head *pool, void *ptr, const void *caller)
+{
+ struct pool_cache_item *item = (struct pool_cache_item *)ptr;
+ struct pool_cache_head *ph = &pool->cache[tid];
+
+ BUG_ON(pool_debugging & POOL_DBG_NO_CACHE);
+
+ LIST_INSERT(&ph->list, &item->by_pool);
+ LIST_INSERT(&th_ctx->pool_lru_head, &item->by_lru);
+ POOL_DEBUG_TRACE_CALLER(pool, item, caller);
+ ph->count++;
+ if (unlikely(pool_debugging & POOL_DBG_INTEGRITY))
+ pool_fill_pattern(ph, item, pool->size);
+ pool_cache_count++;
+ pool_cache_bytes += pool->size;
+
+ if (unlikely(pool_cache_bytes > CONFIG_HAP_POOL_CACHE_SIZE * 3 / 4)) {
+ if (ph->count >= 16 + pool_cache_count / 8 + CONFIG_HAP_POOL_CLUSTER_SIZE)
+ pool_evict_from_local_cache(pool, 0);
+ if (pool_cache_bytes > CONFIG_HAP_POOL_CACHE_SIZE)
+ pool_evict_from_local_caches();
+ }
+}
+
+/* Tries to refill the local cache <pch> from the shared one for pool <pool>.
+ * This is only used when pools are in use and shared pools are enabled. No
+ * malloc() is attempted, and poisonning is never performed. The purpose is to
+ * get the fastest possible refilling so that the caller can easily check if
+ * the cache has enough objects for its use. Must not be used when pools are
+ * disabled.
+ */
+void pool_refill_local_from_shared(struct pool_head *pool, struct pool_cache_head *pch)
+{
+ struct pool_cache_item *item;
+ struct pool_item *ret, *down;
+ uint count;
+
+ BUG_ON(pool_debugging & POOL_DBG_NO_CACHE);
+
+ /* we'll need to reference the first element to figure the next one. We
+ * must temporarily lock it so that nobody allocates then releases it,
+ * or the dereference could fail.
+ */
+ ret = _HA_ATOMIC_LOAD(&pool->free_list);
+ do {
+ while (unlikely(ret == POOL_BUSY)) {
+ __ha_cpu_relax();
+ ret = _HA_ATOMIC_LOAD(&pool->free_list);
+ }
+ if (ret == NULL)
+ return;
+ } while (unlikely((ret = _HA_ATOMIC_XCHG(&pool->free_list, POOL_BUSY)) == POOL_BUSY));
+
+ if (unlikely(ret == NULL)) {
+ HA_ATOMIC_STORE(&pool->free_list, NULL);
+ return;
+ }
+
+ /* this releases the lock */
+ HA_ATOMIC_STORE(&pool->free_list, ret->next);
+
+ /* now store the retrieved object(s) into the local cache */
+ count = 0;
+ for (; ret; ret = down) {
+ down = ret->down;
+ item = (struct pool_cache_item *)ret;
+ POOL_DEBUG_TRACE_CALLER(pool, item, NULL);
+ LIST_INSERT(&pch->list, &item->by_pool);
+ LIST_INSERT(&th_ctx->pool_lru_head, &item->by_lru);
+ count++;
+ if (unlikely(pool_debugging & POOL_DBG_INTEGRITY))
+ pool_fill_pattern(pch, item, pool->size);
+ }
+ HA_ATOMIC_ADD(&pool->used, count);
+ pch->count += count;
+ pool_cache_count += count;
+ pool_cache_bytes += count * pool->size;
+}
+
+/* Adds pool item cluster <item> to the shared cache, which contains <count>
+ * elements. The caller is advised to first check using pool_releasable() if
+ * it's wise to add this series of objects there. Both the pool and the item's
+ * head must be valid.
+ */
+void pool_put_to_shared_cache(struct pool_head *pool, struct pool_item *item, uint count)
+{
+ struct pool_item *free_list;
+
+ _HA_ATOMIC_SUB(&pool->used, count);
+ free_list = _HA_ATOMIC_LOAD(&pool->free_list);
+ do {
+ while (unlikely(free_list == POOL_BUSY)) {
+ __ha_cpu_relax();
+ free_list = _HA_ATOMIC_LOAD(&pool->free_list);
+ }
+ _HA_ATOMIC_STORE(&item->next, free_list);
+ __ha_barrier_atomic_store();
+ } while (!_HA_ATOMIC_CAS(&pool->free_list, &free_list, item));
+ __ha_barrier_atomic_store();
+ swrate_add(&pool->needed_avg, POOL_AVG_SAMPLES, pool->used);
+}
+
+/*
+ * This function frees whatever can be freed in pool <pool>.
+ */
+void pool_flush(struct pool_head *pool)
+{
+ struct pool_item *next, *temp, *down;
+
+ if (!pool || (pool_debugging & (POOL_DBG_NO_CACHE|POOL_DBG_NO_GLOBAL)))
+ return;
+
+ /* The loop below atomically detaches the head of the free list and
+ * replaces it with a NULL. Then the list can be released.
+ */
+ next = pool->free_list;
+ do {
+ while (unlikely(next == POOL_BUSY)) {
+ __ha_cpu_relax();
+ next = _HA_ATOMIC_LOAD(&pool->free_list);
+ }
+ if (next == NULL)
+ return;
+ } while (unlikely((next = _HA_ATOMIC_XCHG(&pool->free_list, POOL_BUSY)) == POOL_BUSY));
+ _HA_ATOMIC_STORE(&pool->free_list, NULL);
+ __ha_barrier_atomic_store();
+
+ while (next) {
+ temp = next;
+ next = temp->next;
+ for (; temp; temp = down) {
+ down = temp->down;
+ pool_put_to_os(pool, temp);
+ }
+ }
+ /* here, we should have pool->allocated == pool->used */
+}
+
+/*
+ * This function frees whatever can be freed in all pools, but respecting
+ * the minimum thresholds imposed by owners. It makes sure to be alone to
+ * run by using thread_isolate(). <pool_ctx> is unused.
+ */
+void pool_gc(struct pool_head *pool_ctx)
+{
+ struct pool_head *entry;
+ int isolated = thread_isolated();
+
+ if (!isolated)
+ thread_isolate();
+
+ list_for_each_entry(entry, &pools, list) {
+ struct pool_item *temp, *down;
+
+ while (entry->free_list &&
+ (int)(entry->allocated - entry->used) > (int)entry->minavail) {
+ temp = entry->free_list;
+ entry->free_list = temp->next;
+ for (; temp; temp = down) {
+ down = temp->down;
+ pool_put_to_os(entry, temp);
+ }
+ }
+ }
+
+ trim_all_pools();
+
+ if (!isolated)
+ thread_release();
+}
+
+/*
+ * Returns a pointer to type <type> taken from the pool <pool_type> or
+ * dynamically allocated. In the first case, <pool_type> is updated to point to
+ * the next element in the list. <flags> is a binary-OR of POOL_F_* flags.
+ * Prefer using pool_alloc() which does the right thing without flags.
+ */
+void *__pool_alloc(struct pool_head *pool, unsigned int flags)
+{
+ void *p = NULL;
+ void *caller = __builtin_return_address(0);
+
+ if (unlikely(pool_debugging & POOL_DBG_FAIL_ALLOC))
+ if (!(flags & POOL_F_NO_FAIL) && mem_should_fail(pool))
+ return NULL;
+
+ if (likely(!(pool_debugging & POOL_DBG_NO_CACHE)) && !p)
+ p = pool_get_from_cache(pool, caller);
+
+ if (unlikely(!p))
+ p = pool_alloc_nocache(pool);
+
+ if (likely(p)) {
+ if (unlikely(flags & POOL_F_MUST_ZERO))
+ memset(p, 0, pool->size);
+ else if (unlikely(!(flags & POOL_F_NO_POISON) && (pool_debugging & POOL_DBG_POISON)))
+ memset(p, mem_poison_byte, pool->size);
+ }
+ return p;
+}
+
+/*
+ * Puts a memory area back to the corresponding pool. <ptr> be valid. Using
+ * pool_free() is preferred.
+ */
+void __pool_free(struct pool_head *pool, void *ptr)
+{
+ const void *caller = __builtin_return_address(0);
+
+ /* we'll get late corruption if we refill to the wrong pool or double-free */
+ POOL_DEBUG_CHECK_MARK(pool, ptr);
+ POOL_DEBUG_RESET_MARK(pool, ptr);
+
+ if (unlikely(pool_debugging & POOL_DBG_NO_CACHE)) {
+ pool_free_nocache(pool, ptr);
+ return;
+ }
+
+ pool_put_to_cache(pool, ptr, caller);
+}
+
+
+#ifdef DEBUG_UAF
+
+/************* use-after-free allocator *************/
+
+/* allocates an area of size <size> and returns it. The semantics are similar
+ * to those of malloc(). However the allocation is rounded up to 4kB so that a
+ * full page is allocated. This ensures the object can be freed alone so that
+ * future dereferences are easily detected. The returned object is always
+ * 16-bytes aligned to avoid issues with unaligned structure objects. In case
+ * some padding is added, the area's start address is copied at the end of the
+ * padding to help detect underflows.
+ */
+void *pool_alloc_area_uaf(size_t size)
+{
+ size_t pad = (4096 - size) & 0xFF0;
+ void *ret;
+
+ ret = mmap(NULL, (size + 4095) & -4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+ if (ret != MAP_FAILED) {
+ /* let's dereference the page before returning so that the real
+ * allocation in the system is performed without holding the lock.
+ */
+ *(int *)ret = 0;
+ if (pad >= sizeof(void *))
+ *(void **)(ret + pad - sizeof(void *)) = ret + pad;
+ ret += pad;
+ } else {
+ ret = NULL;
+ }
+ return ret;
+}
+
+/* frees an area <area> of size <size> allocated by pool_alloc_area(). The
+ * semantics are identical to free() except that the size must absolutely match
+ * the one passed to pool_alloc_area(). In case some padding is added, the
+ * area's start address is compared to the one at the end of the padding, and
+ * a segfault is triggered if they don't match, indicating an underflow.
+ */
+void pool_free_area_uaf(void *area, size_t size)
+{
+ size_t pad = (4096 - size) & 0xFF0;
+
+ if (pad >= sizeof(void *) && *(void **)(area - sizeof(void *)) != area)
+ ABORT_NOW();
+
+ munmap(area - pad, (size + 4095) & -4096);
+}
+
+#endif /* DEBUG_UAF */
+
+/*
+ * This function destroys a pool by freeing it completely, unless it's still
+ * in use. This should be called only under extreme circumstances. It always
+ * returns NULL if the resulting pool is empty, easing the clearing of the old
+ * pointer, otherwise it returns the pool.
+ * .
+ */
+void *pool_destroy(struct pool_head *pool)
+{
+ if (pool) {
+ if (!(pool_debugging & POOL_DBG_NO_CACHE))
+ pool_evict_from_local_cache(pool, 1);
+
+ pool_flush(pool);
+ if (pool->used)
+ return pool;
+ pool->users--;
+ if (!pool->users) {
+ LIST_DELETE(&pool->list);
+ /* note that if used == 0, the cache is empty */
+ free(pool->base_addr);
+ }
+ }
+ return NULL;
+}
+
+/* This destroys all pools on exit. It is *not* thread safe. */
+void pool_destroy_all()
+{
+ struct pool_head *entry, *back;
+
+ list_for_each_entry_safe(entry, back, &pools, list) {
+ /* there's only one occurrence of each pool in the list,
+ * and we're existing instead of looping on the whole
+ * list just to decrement users, force it to 1 here.
+ */
+ entry->users = 1;
+ pool_destroy(entry);
+ }
+}
+
+/* This function dumps memory usage information into the trash buffer. */
+void dump_pools_to_trash()
+{
+ struct pool_head *entry;
+ unsigned long long allocated, used;
+ int nbpools;
+ unsigned long long cached_bytes = 0;
+ uint cached = 0;
+
+ allocated = used = nbpools = 0;
+ chunk_printf(&trash, "Dumping pools usage. Use SIGQUIT to flush them.\n");
+ list_for_each_entry(entry, &pools, list) {
+ if (!(pool_debugging & POOL_DBG_NO_CACHE)) {
+ int i;
+ for (cached = i = 0; i < global.nbthread; i++)
+ cached += entry->cache[i].count;
+ cached_bytes += cached * (ullong)entry->size;
+ }
+ chunk_appendf(&trash, " - Pool %s (%u bytes) : %u allocated (%llu bytes), %u used"
+ " (~%u by thread caches)"
+ ", needed_avg %u, %u failures, %u users, @%p%s\n",
+ entry->name, entry->size, entry->allocated,
+ (ullong)entry->size * entry->allocated, entry->used,
+ cached,
+ swrate_avg(entry->needed_avg, POOL_AVG_SAMPLES), entry->failed,
+ entry->users, entry,
+ (entry->flags & MEM_F_SHARED) ? " [SHARED]" : "");
+
+ allocated += entry->allocated * (ullong)entry->size;
+ used += entry->used * (ullong)entry->size;
+ nbpools++;
+ }
+ chunk_appendf(&trash, "Total: %d pools, %llu bytes allocated, %llu used"
+ " (~%llu by thread caches)"
+ ".\n",
+ nbpools, allocated, used, cached_bytes
+ );
+}
+
+/* Dump statistics on pools usage. */
+void dump_pools(void)
+{
+ dump_pools_to_trash();
+ qfprintf(stderr, "%s", trash.area);
+}
+
+/* This function returns the total number of failed pool allocations */
+int pool_total_failures()
+{
+ struct pool_head *entry;
+ int failed = 0;
+
+ list_for_each_entry(entry, &pools, list)
+ failed += entry->failed;
+ return failed;
+}
+
+/* This function returns the total amount of memory allocated in pools (in bytes) */
+unsigned long long pool_total_allocated()
+{
+ struct pool_head *entry;
+ unsigned long long allocated = 0;
+
+ list_for_each_entry(entry, &pools, list)
+ allocated += entry->allocated * (ullong)entry->size;
+ return allocated;
+}
+
+/* This function returns the total amount of memory used in pools (in bytes) */
+unsigned long long pool_total_used()
+{
+ struct pool_head *entry;
+ unsigned long long used = 0;
+
+ list_for_each_entry(entry, &pools, list)
+ used += entry->used * (ullong)entry->size;
+ return used;
+}
+
+/* This function parses a string made of a set of debugging features as
+ * specified after -dM on the command line, and will set pool_debugging
+ * accordingly. On success it returns a strictly positive value. It may zero
+ * with the first warning in <err>, -1 with a help message in <err>, or -2 with
+ * the first error in <err> return the first error in <err>. <err> is undefined
+ * on success, and will be non-null and locally allocated on help/error/warning.
+ * The caller must free it. Warnings are used to report features that were not
+ * enabled at build time, and errors are used to report unknown features.
+ */
+int pool_parse_debugging(const char *str, char **err)
+{
+ struct ist args;
+ char *end;
+ uint new_dbg;
+ int v;
+
+
+ /* if it's empty or starts with a number, it's the mem poisonning byte */
+ v = strtol(str, &end, 0);
+ if (!*end || *end == ',') {
+ mem_poison_byte = *str ? v : 'P';
+ if (mem_poison_byte >= 0)
+ pool_debugging |= POOL_DBG_POISON;
+ else
+ pool_debugging &= ~POOL_DBG_POISON;
+ str = end;
+ }
+
+ new_dbg = pool_debugging;
+
+ for (args = ist(str); istlen(args); args = istadv(istfind(args, ','), 1)) {
+ struct ist feat = iststop(args, ',');
+
+ if (!istlen(feat))
+ continue;
+
+ if (isteq(feat, ist("help"))) {
+ ha_free(err);
+ memprintf(err,
+ "-dM alone enables memory poisonning with byte 0x50 on allocation. A numeric\n"
+ "value may be appended immediately after -dM to use another value (0 supported).\n"
+ "Then an optional list of comma-delimited keywords may be appended to set or\n"
+ "clear some debugging options ('*' marks the current setting):\n\n"
+ " set clear description\n"
+ " -----------------+-----------------+-----------------------------------------\n");
+
+ for (v = 0; dbg_options[v].flg; v++) {
+ memprintf(err, "%s %c %-15s|%c %-15s| %s\n",
+ *err,
+ (pool_debugging & dbg_options[v].flg) ? '*' : ' ',
+ dbg_options[v].set,
+ (pool_debugging & dbg_options[v].flg) ? ' ' : '*',
+ dbg_options[v].clr,
+ dbg_options[v].hlp);
+ }
+ return -1;
+ }
+
+ for (v = 0; dbg_options[v].flg; v++) {
+ if (isteq(feat, ist(dbg_options[v].set))) {
+ new_dbg |= dbg_options[v].flg;
+ break;
+ }
+ else if (isteq(feat, ist(dbg_options[v].clr))) {
+ new_dbg &= ~dbg_options[v].flg;
+ break;
+ }
+ }
+
+ if (!dbg_options[v].flg) {
+ memprintf(err, "unknown pool debugging feature <%.*s>", (int)istlen(feat), istptr(feat));
+ return -2;
+ }
+ }
+
+ pool_debugging = new_dbg;
+ return 1;
+}
+
+/* This function dumps memory usage information onto the stream connector's
+ * read buffer. It returns 0 as long as it does not complete, non-zero upon
+ * completion. No state is used.
+ */
+static int cli_io_handler_dump_pools(struct appctx *appctx)
+{
+ dump_pools_to_trash();
+ if (applet_putchk(appctx, &trash) == -1)
+ return 0;
+ return 1;
+}
+
+/* callback used to create early pool <name> of size <size> and store the
+ * resulting pointer into <ptr>. If the allocation fails, it quits with after
+ * emitting an error message.
+ */
+void create_pool_callback(struct pool_head **ptr, char *name, unsigned int size)
+{
+ *ptr = create_pool(name, size, MEM_F_SHARED);
+ if (!*ptr) {
+ ha_alert("Failed to allocate pool '%s' of size %u : %s. Aborting.\n",
+ name, size, strerror(errno));
+ exit(1);
+ }
+}
+
+/* Initializes all per-thread arrays on startup */
+static void init_pools()
+{
+ int thr;
+
+ for (thr = 0; thr < MAX_THREADS; thr++) {
+ LIST_INIT(&ha_thread_ctx[thr].pool_lru_head);
+ }
+
+ detect_allocator();
+}
+
+INITCALL0(STG_PREPARE, init_pools);
+
+/* Report in build options if trim is supported */
+static void pools_register_build_options(void)
+{
+ if (is_trim_enabled()) {
+ char *ptr = NULL;
+ memprintf(&ptr, "Support for malloc_trim() is enabled.");
+ hap_register_build_opts(ptr, 1);
+ }
+}
+INITCALL0(STG_REGISTER, pools_register_build_options);
+
+/* register cli keywords */
+static struct cli_kw_list cli_kws = {{ },{
+ { { "show", "pools", NULL }, "show pools : report information about the memory pools usage", NULL, cli_io_handler_dump_pools },
+ {{},}
+}};
+
+INITCALL1(STG_REGISTER, cli_register_kw, &cli_kws);
+
+
+/* config parser for global "tune.fail-alloc" */
+static int mem_parse_global_fail_alloc(char **args, int section_type, struct proxy *curpx,
+ const struct proxy *defpx, const char *file, int line,
+ char **err)
+{
+ if (too_many_args(1, args, err, NULL))
+ return -1;
+ mem_fail_rate = atoi(args[1]);
+ if (mem_fail_rate < 0 || mem_fail_rate > 100) {
+ memprintf(err, "'%s' expects a numeric value between 0 and 100.", args[0]);
+ return -1;
+ }
+ return 0;
+}
+
+/* config parser for global "no-memory-trimming" */
+static int mem_parse_global_no_mem_trim(char **args, int section_type, struct proxy *curpx,
+ const struct proxy *defpx, const char *file, int line,
+ char **err)
+{
+ if (too_many_args(0, args, err, NULL))
+ return -1;
+ disable_trim = 1;
+ return 0;
+}
+
+/* register global config keywords */
+static struct cfg_kw_list mem_cfg_kws = {ILH, {
+ { CFG_GLOBAL, "tune.fail-alloc", mem_parse_global_fail_alloc },
+ { CFG_GLOBAL, "no-memory-trimming", mem_parse_global_no_mem_trim },
+ { 0, NULL, NULL }
+}};
+
+INITCALL1(STG_REGISTER, cfg_register_keywords, &mem_cfg_kws);
+
+/*
+ * Local variables:
+ * c-indent-level: 8
+ * c-basic-offset: 8
+ * End:
+ */