Adding upstream version 2.9.5.upstream/2.9.5

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1539 insertions, 0 deletions

diff --git a/src/pool.c b/src/pool.c
new file mode 100644
index 0000000..376b311
--- /dev/null
+++ b/src/pool.c
@@ -0,0 +1,1539 @@
+/*
+ * 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 <errno.h>
+
+#include <import/plock.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/pool-os.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';
+int pool_trim_in_progress = 0;
+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
+#if defined(DEBUG_NO_POOLS) || defined(DEBUG_UAF)
+	POOL_DBG_NO_CACHE   |
+#endif
+#if defined(DEBUG_POOL_TRACING)
+	POOL_DBG_CALLER     |
+#endif
+#if defined(DEBUG_MEMORY_POOLS)
+	POOL_DBG_TAG        |
+#endif
+#if defined(DEBUG_UAF)
+	POOL_DBG_UAF        |
+#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" },
+	{ POOL_DBG_UAF,        "uaf",        "no-uaf",       "enable use-after-free checks (slow)" },
+	{ 0 /* end */ }
+};
+
+/* describes a snapshot of a pool line about to be dumped by "show pools" */
+struct pool_dump_info {
+	const struct pool_head *entry;
+	ulong alloc_items;
+	ulong alloc_bytes;
+	ulong used_items;
+	ulong cached_items;
+	ulong need_avg;
+	ulong failed_items;
+};
+
+/* context used by "show pools" */
+struct show_pools_ctx {
+	char *prefix;  /* if non-null, match this prefix name for the pool */
+	int by_what; /* 0=no sort, 1=by name, 2=by item size, 3=by total alloc */
+	int maxcnt;  /* 0=no limit, other=max number of output entries */
+};
+
+static int mem_fail_rate __read_mostly = 0;
+static int using_default_allocator __read_mostly = 1; // linked-in allocator or LD_PRELOADed one ?
+static int disable_trim __read_mostly = 0;
+static int(*my_mallctl)(const char *, void *, size_t *, void *, size_t) = NULL;
+static int(*_malloc_trim)(size_t) = NULL;
+
+/* returns the pool hash bucket an object should use based on its pointer.
+ * Objects will needed consistent bucket assignment so that they may be
+ * allocated on one thread and released on another one. Thus only the
+ * pointer is usable.
+ */
+static forceinline unsigned int pool_pbucket(const void *ptr)
+{
+	return ptr_hash(ptr, CONFIG_HAP_POOL_BUCKETS_BITS);
+}
+
+/* returns the pool hash bucket to use for the current thread. This should only
+ * be used when no pointer is available (e.g. count alloc failures).
+ */
+static forceinline unsigned int pool_tbucket(void)
+{
+	return tid % CONFIG_HAP_POOL_BUCKETS;
+}
+
+/* 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.
+ */
+void trim_all_pools(void)
+{
+	int isolated = thread_isolated();
+
+	if (!isolated)
+		thread_isolate();
+
+	malloc_trim(0);
+
+	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) {
+		/* trick: we won't enter here if mallctl() is known at link
+		 * time. This allows to detect if the symbol was changed since
+		 * the program was linked, indicating it's not running on the
+		 * expected allocator (due to an LD_PRELOAD) and that we must
+		 * be extra cautious and avoid some optimizations that are
+		 * known to break such as malloc_trim().
+		 */
+		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
+	}
+
+	/* detect presence of malloc_trim() */
+	_malloc_trim = get_sym_next_addr("malloc_trim");
+}
+
+/* replace the libc's malloc_trim() so that we can also intercept the calls
+ * from child libraries when the allocator is not the default one.
+ */
+int malloc_trim(size_t pad)
+{
+	int ret = 0;
+
+	if (disable_trim)
+		return ret;
+
+	HA_ATOMIC_INC(&pool_trim_in_progress);
+
+	if (my_mallctl) {
+		/* here we're on jemalloc and malloc_trim() is called either
+		 * by haproxy or another dependency (the worst case that
+		 * normally crashes). Instead of just failing, we can actually
+		 * emulate it so let's do it now.
+		 */
+		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);
+				ret = 1; // success
+			}
+		}
+	}
+	else if (!using_default_allocator) {
+		/* special allocators that can be LD_PRELOADed end here */
+		ret = 0; // did nothing
+	}
+	else if (_malloc_trim) {
+		/* we're typically on glibc and not overridden */
+		ret = _malloc_trim(pad);
+	}
+#if defined(HA_HAVE_MALLOC_ZONE)
+	else {
+		/* we're on MacOS, there's an equivalent mechanism */
+		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);
+					ret = 1; // success
+				}
+			}
+		}
+	}
+#endif
+	HA_ATOMIC_DEC(&pool_trim_in_progress);
+
+	/* here we have ret=0 if nothing was release, or 1 if some were */
+	return ret;
+}
+
+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;
+
+	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 (!(pool_debugging & POOL_DBG_NO_CACHE)) {
+		/* we'll store two lists there, we need the room for this. Let's
+		 * make sure it's always OK even when including the extra word
+		 * that is stored after the pci struct.
+		 */
+		if (size + extra - extra_caller < sizeof(struct pool_cache_item))
+			size = sizeof(struct pool_cache_item) + extra_caller - extra;
+	}
+
+	/* Now we know our size is set to the strict minimum possible. It may
+	 * be OK for elements allocated with an exact size (e.g. buffers), but
+	 * we're going to round the size up 16 bytes to merge almost identical
+	 * pools together. We only round up however when we add the debugging
+	 * tag since it's used to detect overflows. Otherwise we only round up
+	 * to the size of a word to preserve alignment.
+	 */
+	if (!(flags & MEM_F_EXACT)) {
+		align = (pool_debugging & POOL_DBG_TAG) ? sizeof(void *) : 16;
+		size  = ((size + align - 1) & -align);
+	}
+
+	/* 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 but NOT
+ * updated, this is left to the caller, and but no other checks are performed.
+ */
+void *pool_get_from_os_noinc(struct pool_head *pool)
+{
+	if (!pool->limit || pool_allocated(pool) < pool->limit) {
+		void *ptr;
+
+		if (pool_debugging & POOL_DBG_UAF)
+			ptr = pool_alloc_area_uaf(pool->alloc_sz);
+		else
+			ptr = pool_alloc_area(pool->alloc_sz);
+		if (ptr)
+			return ptr;
+		_HA_ATOMIC_INC(&pool->buckets[pool_tbucket()].failed);
+	}
+	activity[tid].pool_fail++;
+	return NULL;
+
+}
+
+/* Releases a pool item back to the operating system but DOES NOT update
+ * the allocation counter, it's left to the caller to do it. It may be
+ * done before or after, it doesn't matter, the function does not use it.
+ */
+void pool_put_to_os_nodec(struct pool_head *pool, void *ptr)
+{
+	if (pool_debugging & POOL_DBG_UAF)
+		pool_free_area_uaf(ptr, pool->alloc_sz);
+	else
+		pool_free_area(ptr, pool->alloc_sz);
+}
+
+/* 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, const void *caller)
+{
+	void *ptr = NULL;
+	uint bucket;
+
+	ptr = pool_get_from_os_noinc(pool);
+	if (!ptr)
+		return NULL;
+
+	bucket = pool_pbucket(ptr);
+	swrate_add_scaled_opportunistic(&pool->buckets[bucket].needed_avg, POOL_AVG_SAMPLES, pool->buckets[bucket].used, POOL_AVG_SAMPLES/4);
+	_HA_ATOMIC_INC(&pool->buckets[bucket].allocated);
+	_HA_ATOMIC_INC(&pool->buckets[bucket].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, caller);
+	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)
+{
+	uint bucket = pool_pbucket(ptr);
+
+	_HA_ATOMIC_DEC(&pool->buckets[bucket].used);
+	_HA_ATOMIC_DEC(&pool->buckets[bucket].allocated);
+	swrate_add_opportunistic(&pool->buckets[bucket].needed_avg, POOL_AVG_SAMPLES, pool->buckets[bucket].used);
+
+	pool_put_to_os_nodec(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_head *pool, struct pool_cache_item *item, const void *caller)
+{
+	const ulong *ptr = (const ulong *)item;
+	uint size = pool->size;
+	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)) {
+			pool_inspect_item("cache corruption detected", pool, item, caller);
+			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;
+	void *caller = __builtin_return_address(0);
+	uint released = 0;
+	uint cluster = 0;
+	uint to_free_max;
+	uint bucket;
+
+	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, pool, item, caller);
+		LIST_DELETE(&item->by_pool);
+		LIST_DELETE(&item->by_lru);
+
+		bucket = pool_pbucket(item);
+		_HA_ATOMIC_DEC(&pool->buckets[bucket].used);
+		swrate_add_opportunistic(&pool->buckets[bucket].needed_avg, POOL_AVG_SAMPLES, pool->buckets[bucket].used);
+
+		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 = 0;
+				head = NULL;
+			}
+		} else {
+			/* does pool_free_nocache() with a known bucket */
+			_HA_ATOMIC_DEC(&pool->buckets[bucket].allocated);
+			pool_put_to_os_nodec(pool, item);
+		}
+
+		released++;
+	}
+
+	/* incomplete cluster left */
+	if (cluster)
+		pool_put_to_shared_cache(pool, head);
+
+	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 > global.tune.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 > global.tune.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' perspective. 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 > global.tune.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 > global.tune.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 bucket;
+	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. In order to limit the locking,
+	 * threads start from a bucket that depends on their ID.
+	 */
+
+	bucket = pool_tbucket();
+	ret = _HA_ATOMIC_LOAD(&pool->buckets[bucket].free_list);
+	count = 0;
+	do {
+		/* look for an apparently non-busy entry. If we hit a busy pool
+		 * we retry with another random bucket. And if we encounter a
+		 * NULL, we retry once with another random bucket. This is in
+		 * order to prevent object accumulation in other buckets.
+		 */
+		while (unlikely(ret == POOL_BUSY || (ret == NULL && count++ < 1))) {
+			bucket = statistical_prng() % CONFIG_HAP_POOL_BUCKETS;
+			ret = _HA_ATOMIC_LOAD(&pool->buckets[bucket].free_list);
+		}
+		if (ret == NULL)
+			return;
+	} while (unlikely((ret = _HA_ATOMIC_XCHG(&pool->buckets[bucket].free_list, POOL_BUSY)) == POOL_BUSY));
+
+	if (unlikely(ret == NULL)) {
+		HA_ATOMIC_STORE(&pool->buckets[bucket].free_list, NULL);
+		return;
+	}
+
+	/* this releases the lock */
+	HA_ATOMIC_STORE(&pool->buckets[bucket].free_list, ret->next);
+
+	/* now store the retrieved object(s) into the local cache. Note that
+	 * they don't all have the same hash and that it doesn't necessarily
+	 * match the one from the pool.
+	 */
+	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);
+		_HA_ATOMIC_INC(&pool->buckets[pool_pbucket(item)].used);
+		count++;
+		if (unlikely(pool_debugging & POOL_DBG_INTEGRITY))
+			pool_fill_pattern(pch, item, pool->size);
+
+	}
+	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)
+{
+	struct pool_item *free_list;
+	uint bucket = pool_pbucket(item);
+
+	/* we prefer to put the item into the entry that corresponds to its own
+	 * hash so that on return it remains in the right place, but that's not
+	 * mandatory.
+	 */
+	free_list = _HA_ATOMIC_LOAD(&pool->buckets[bucket].free_list);
+	do {
+		/* look for an apparently non-busy entry */
+		while (unlikely(free_list == POOL_BUSY)) {
+			bucket = (bucket + 1) % CONFIG_HAP_POOL_BUCKETS;
+			free_list = _HA_ATOMIC_LOAD(&pool->buckets[bucket].free_list);
+		}
+		_HA_ATOMIC_STORE(&item->next, free_list);
+		__ha_barrier_atomic_store();
+	} while (!_HA_ATOMIC_CAS(&pool->buckets[bucket].free_list, &free_list, item));
+	__ha_barrier_atomic_store();
+}
+
+/*
+ * This function frees whatever can be freed in pool <pool>.
+ */
+void pool_flush(struct pool_head *pool)
+{
+	struct pool_item *next, *temp, *down;
+	uint bucket;
+
+	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.
+	 */
+	for (bucket = 0; bucket < CONFIG_HAP_POOL_BUCKETS; bucket++) {
+		next = pool->buckets[bucket].free_list;
+		while (1) {
+			while (unlikely(next == POOL_BUSY))
+				next = (void*)pl_wait_new_long((ulong*)&pool->buckets[bucket].free_list, (ulong)next);
+
+			if (next == NULL)
+				break;
+
+			next = _HA_ATOMIC_XCHG(&pool->buckets[bucket].free_list, POOL_BUSY);
+			if (next != POOL_BUSY) {
+				HA_ATOMIC_STORE(&pool->buckets[bucket].free_list, NULL);
+				break;
+			}
+		}
+
+		while (next) {
+			temp = next;
+			next = temp->next;
+			for (; temp; temp = down) {
+				down = temp->down;
+				_HA_ATOMIC_DEC(&pool->buckets[pool_pbucket(temp)].allocated);
+				pool_put_to_os_nodec(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;
+		uint allocated = pool_allocated(entry);
+		uint used = pool_used(entry);
+		int bucket = 0;
+
+		while ((int)(allocated - used) > (int)entry->minavail) {
+			/* ok let's find next entry to evict */
+			while (!entry->buckets[bucket].free_list && bucket < CONFIG_HAP_POOL_BUCKETS)
+				bucket++;
+
+			if (bucket >= CONFIG_HAP_POOL_BUCKETS)
+				break;
+
+			temp = entry->buckets[bucket].free_list;
+			entry->buckets[bucket].free_list = temp->next;
+			for (; temp; temp = down) {
+				down = temp->down;
+				allocated--;
+				_HA_ATOMIC_DEC(&entry->buckets[pool_pbucket(temp)].allocated);
+				pool_put_to_os_nodec(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, caller);
+
+	if (likely(p)) {
+#ifdef USE_MEMORY_PROFILING
+		if (unlikely(profiling & HA_PROF_MEMORY)) {
+			extern struct memprof_stats memprof_stats[MEMPROF_HASH_BUCKETS + 1];
+			struct memprof_stats *bin;
+
+			bin = memprof_get_bin(__builtin_return_address(0), MEMPROF_METH_P_ALLOC);
+			_HA_ATOMIC_ADD(&bin->alloc_calls, 1);
+			_HA_ATOMIC_ADD(&bin->alloc_tot, pool->size);
+			_HA_ATOMIC_STORE(&bin->info, pool);
+			/* replace the caller with the allocated bin: this way
+			 * we'll the pool_free() call will be able to update our
+			 * entry. We only do it for non-colliding entries though,
+			 * since these ones store the true caller location.
+			 */
+			if (bin >= &memprof_stats[0] && bin < &memprof_stats[MEMPROF_HASH_BUCKETS])
+				POOL_DEBUG_TRACE_CALLER(pool, (struct pool_cache_item *)p, bin);
+		}
+#endif
+		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, caller);
+	POOL_DEBUG_RESET_MARK(pool, ptr);
+
+#ifdef USE_MEMORY_PROFILING
+	if (unlikely(profiling & HA_PROF_MEMORY) && ptr) {
+		extern struct memprof_stats memprof_stats[MEMPROF_HASH_BUCKETS + 1];
+		struct memprof_stats *bin;
+
+		bin = memprof_get_bin(__builtin_return_address(0), MEMPROF_METH_P_FREE);
+		_HA_ATOMIC_ADD(&bin->free_calls, 1);
+		_HA_ATOMIC_ADD(&bin->free_tot, pool->size);
+		_HA_ATOMIC_STORE(&bin->info, pool);
+
+		/* check if the caller is an allocator, and if so, let's update
+		 * its free() count.
+		 */
+		bin = *(struct memprof_stats**)(((char *)ptr) + pool->alloc_sz - sizeof(void*));
+		if (bin >= &memprof_stats[0] && bin < &memprof_stats[MEMPROF_HASH_BUCKETS]) {
+			_HA_ATOMIC_ADD(&bin->free_calls, 1);
+			_HA_ATOMIC_ADD(&bin->free_tot, pool->size);
+		}
+	}
+#endif
+
+	if (unlikely((pool_debugging & POOL_DBG_NO_CACHE) ||
+		     global.tune.pool_cache_size < pool->size)) {
+		pool_free_nocache(pool, ptr);
+		return;
+	}
+
+	pool_put_to_cache(pool, ptr, caller);
+}
+
+/*
+ * 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(pool))
+			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);
+	}
+}
+
+/* carefully inspects an item upon fatal error and emit diagnostics */
+void pool_inspect_item(const char *msg, struct pool_head *pool, const void *item, const void *caller)
+{
+	const struct pool_head *the_pool = NULL;
+
+	chunk_printf(&trash,
+		     "FATAL: pool inconsistency detected in thread %d: %s.\n"
+		     "  caller: %p (",
+		     tid + 1, msg, caller);
+
+	resolve_sym_name(&trash, NULL, caller);
+
+	chunk_appendf(&trash,
+		      ")\n"
+		      "  item: %p\n"
+		      "  pool: %p ('%s', size %u, real %u, users %u)\n",
+		      item, pool, pool->name, pool->size, pool->alloc_sz, pool->users);
+
+	if (pool_debugging & POOL_DBG_TAG) {
+		const void **pool_mark;
+		struct pool_head *ph;
+		const void *tag;
+
+		pool_mark = (const void **)(((char *)item) + pool->size);
+		tag =  may_access(pool_mark) ? *pool_mark : NULL;
+		if (tag == pool) {
+			chunk_appendf(&trash, "  tag: @%p = %p (%s)\n", pool_mark, tag, pool->name);
+			the_pool = pool;
+		}
+		else {
+			if (!may_access(pool_mark))
+				chunk_appendf(&trash, "Tag not accessible. ");
+			else
+				chunk_appendf(&trash, "Tag does not match (%p). ", tag);
+
+			list_for_each_entry(ph, &pools, list) {
+				pool_mark = (const void **)(((char *)item) + ph->size);
+				if (!may_access(pool_mark))
+					continue;
+				tag =  *pool_mark;
+
+				if (tag == ph) {
+					if (!the_pool)
+						chunk_appendf(&trash, "Possible origin pool(s):\n");
+
+					chunk_appendf(&trash, "  tag: @%p = %p (%s, size %u, real %u, users %u)\n",
+						      pool_mark, tag, ph->name, ph->size, ph->alloc_sz, ph->users);
+					if (!the_pool || the_pool->size < ph->size)
+						the_pool = ph;
+				}
+			}
+
+			if (!the_pool) {
+				const char *start, *end, *p;
+
+				pool_mark = (const void **)(((char *)item) + pool->size);
+				chunk_appendf(&trash,
+					      "Tag does not match any other pool.\n"
+					      "Contents around address %p+%lu=%p:\n",
+					      item, (ulong)((const void*)pool_mark - (const void*)item),
+					      pool_mark);
+
+				/* dump in word-sized blocks */
+				start = (const void *)(((uintptr_t)pool_mark - 32) & -sizeof(void*));
+				end   = (const void *)(((uintptr_t)pool_mark + 32 + sizeof(void*) - 1) & -sizeof(void*));
+
+				while (start < end) {
+					dump_addr_and_bytes(&trash, "  ", start, sizeof(void*));
+					chunk_strcat(&trash, " [");
+					for (p = start; p < start + sizeof(void*); p++) {
+						if (!may_access(p))
+							chunk_strcat(&trash, "*");
+						else if (isprint((unsigned char)*p))
+							chunk_appendf(&trash, "%c", *p);
+						else
+							chunk_strcat(&trash, ".");
+					}
+
+					if (may_access(start))
+						tag = *(const void **)start;
+					else
+						tag = NULL;
+
+					if (tag == pool) {
+						/* the pool can often be there so let's detect it */
+						chunk_appendf(&trash, "] [pool:%s", pool->name);
+					}
+					else if (tag) {
+						/* print pointers that resolve to a symbol */
+						size_t back_data = trash.data;
+						chunk_strcat(&trash, "] [");
+						if (!resolve_sym_name(&trash, NULL, tag))
+							trash.data = back_data;
+					}
+
+					chunk_strcat(&trash, "]\n");
+					start = p;
+				}
+			}
+		}
+	}
+
+	if (pool_debugging & POOL_DBG_CALLER) {
+		struct buffer *trash2 = get_trash_chunk();
+		const struct pool_head *ph;
+		const void **pool_mark;
+		const void *tag, *rec_tag;
+
+		ph = the_pool ? the_pool : pool;
+		pool_mark = (const void **)(((char *)item) + ph->alloc_sz - sizeof(void*));
+		rec_tag =  may_access(pool_mark) ? *pool_mark : NULL;
+
+		if (rec_tag && resolve_sym_name(trash2, NULL, rec_tag))
+			chunk_appendf(&trash,
+				      "Recorded caller if pool '%s':\n  @%p (+%04u) = %p (%s)\n",
+				      ph->name, pool_mark, (uint)(ph->alloc_sz - sizeof(void*)),
+				      rec_tag, trash2->area);
+
+		if (!the_pool) {
+			/* the pool couldn't be formally verified */
+			chunk_appendf(&trash, "Other possible callers:\n");
+			list_for_each_entry(ph, &pools, list) {
+				if (ph == pool)
+					continue;
+				pool_mark = (const void **)(((char *)item) + ph->alloc_sz - sizeof(void*));
+				if (!may_access(pool_mark))
+					continue;
+				tag = *pool_mark;
+				if (tag == rec_tag)
+					continue;
+
+				/* see if we can resolve something */
+				chunk_printf(trash2, "@%p (+%04u) = %p (", pool_mark, (uint)(ph->alloc_sz - sizeof(void*)), tag);
+				if (resolve_sym_name(trash2, NULL, tag)) {
+					chunk_appendf(trash2, ")");
+					chunk_appendf(&trash,
+						      "  %s [as pool %s, size %u, real %u, users %u]\n",
+						      trash2->area, ph->name, ph->size, ph->alloc_sz, ph->users);
+				}
+			}
+		}
+	}
+
+	chunk_appendf(&trash, "\n");
+	DISGUISE(write(2, trash.area, trash.data));
+}
+
+/* used by qsort in "show pools" to sort by name */
+static int cmp_dump_pools_name(const void *a, const void *b)
+{
+	const struct pool_dump_info *l = (const struct pool_dump_info *)a;
+	const struct pool_dump_info *r = (const struct pool_dump_info *)b;
+
+	return strcmp(l->entry->name, r->entry->name);
+}
+
+/* used by qsort in "show pools" to sort by item size */
+static int cmp_dump_pools_size(const void *a, const void *b)
+{
+	const struct pool_dump_info *l = (const struct pool_dump_info *)a;
+	const struct pool_dump_info *r = (const struct pool_dump_info *)b;
+
+	if (l->entry->size > r->entry->size)
+		return -1;
+	else if (l->entry->size < r->entry->size)
+		return 1;
+	else
+		return 0;
+}
+
+/* used by qsort in "show pools" to sort by usage */
+static int cmp_dump_pools_usage(const void *a, const void *b)
+{
+	const struct pool_dump_info *l = (const struct pool_dump_info *)a;
+	const struct pool_dump_info *r = (const struct pool_dump_info *)b;
+
+	if (l->alloc_bytes > r->alloc_bytes)
+		return -1;
+	else if (l->alloc_bytes < r->alloc_bytes)
+		return 1;
+	else
+		return 0;
+}
+
+/* will not dump more than this number of entries. Anything beyond this will
+ * likely not fit into a regular output buffer anyway.
+ */
+#define POOLS_MAX_DUMPED_ENTRIES 1024
+
+/* This function dumps memory usage information into the trash buffer.
+ * It may sort by a criterion if <by_what> is non-zero, and limit the
+ * number of output lines if <max> is non-zero. It may limit only to
+ * pools whose names start with <pfx> if <pfx> is non-null.
+ */
+void dump_pools_to_trash(int by_what, int max, const char *pfx)
+{
+	struct pool_dump_info pool_info[POOLS_MAX_DUMPED_ENTRIES];
+	struct pool_head *entry;
+	unsigned long long allocated, used;
+	int nbpools, i;
+	unsigned long long cached_bytes = 0;
+	uint cached = 0;
+	uint alloc_items;
+
+	allocated = used = nbpools = 0;
+
+	list_for_each_entry(entry, &pools, list) {
+		if (nbpools >= POOLS_MAX_DUMPED_ENTRIES)
+			break;
+
+		alloc_items = pool_allocated(entry);
+		/* do not dump unused entries when sorting by usage */
+		if (by_what == 3 && !alloc_items)
+			continue;
+
+		/* verify the pool name if a prefix is requested */
+		if (pfx && strncmp(entry->name, pfx, strlen(pfx)) != 0)
+			continue;
+
+		if (!(pool_debugging & POOL_DBG_NO_CACHE)) {
+			for (cached = i = 0; i < global.nbthread; i++)
+				cached += entry->cache[i].count;
+		}
+		pool_info[nbpools].entry = entry;
+		pool_info[nbpools].alloc_items = alloc_items;
+		pool_info[nbpools].alloc_bytes = (ulong)entry->size * alloc_items;
+		pool_info[nbpools].used_items = pool_used(entry);
+		pool_info[nbpools].cached_items = cached;
+		pool_info[nbpools].need_avg = swrate_avg(pool_needed_avg(entry), POOL_AVG_SAMPLES);
+		pool_info[nbpools].failed_items = pool_failed(entry);
+		nbpools++;
+	}
+
+	if (by_what == 1)  /* sort by name */
+		qsort(pool_info, nbpools, sizeof(pool_info[0]), cmp_dump_pools_name);
+	else if (by_what == 2)  /* sort by item size */
+		qsort(pool_info, nbpools, sizeof(pool_info[0]), cmp_dump_pools_size);
+	else if (by_what == 3)  /* sort by total usage */
+		qsort(pool_info, nbpools, sizeof(pool_info[0]), cmp_dump_pools_usage);
+
+	chunk_printf(&trash, "Dumping pools usage");
+	if (!max || max >= POOLS_MAX_DUMPED_ENTRIES)
+		max = POOLS_MAX_DUMPED_ENTRIES;
+	if (nbpools >= max)
+		chunk_appendf(&trash, " (limited to the first %u entries)", max);
+	chunk_appendf(&trash, ". Use SIGQUIT to flush them.\n");
+
+	for (i = 0; i < nbpools && i < max; i++) {
+		chunk_appendf(&trash, "  - Pool %s (%lu bytes) : %lu allocated (%lu bytes), %lu used"
+			      " (~%lu by thread caches)"
+			      ", needed_avg %lu, %lu failures, %u users, @%p%s\n",
+		              pool_info[i].entry->name, (ulong)pool_info[i].entry->size,
+			      pool_info[i].alloc_items, pool_info[i].alloc_bytes,
+			      pool_info[i].used_items, pool_info[i].cached_items,
+			      pool_info[i].need_avg, pool_info[i].failed_items,
+		              pool_info[i].entry->users, pool_info[i].entry,
+		              (pool_info[i].entry->flags & MEM_F_SHARED) ? " [SHARED]" : "");
+
+		cached_bytes += pool_info[i].cached_items * (ulong)pool_info[i].entry->size;
+		allocated    += pool_info[i].alloc_items  * (ulong)pool_info[i].entry->size;
+		used         += pool_info[i].used_items   * (ulong)pool_info[i].entry->size;
+	}
+
+	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(0, 0, NULL);
+	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 += pool_failed(entry);
+	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 += pool_allocated(entry) * (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 += pool_used(entry) * (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);
+			}
+
+			memprintf(err,
+			          "%s  -----------------+-----------------+-----------------------------------------\n"
+				  "Examples:\n"
+				  "  Disable merging and enable poisonning with byte 'P': -dM0x50,no-merge\n"
+				  "  Randomly fail allocations: -dMfail\n"
+				  "  Detect out-of-bound corruptions: -dMno-merge,tag\n"
+				  "  Detect post-free cache corruptions: -dMno-merge,cold-first,integrity,caller\n"
+				  "  Detect all cache corruptions: -dMno-merge,cold-first,integrity,tag,caller\n"
+				  "  Detect UAF (disables cache, very slow): -dMuaf\n"
+				  "  Detect post-cache UAF: -dMuaf,cache,no-merge,cold-first,integrity,tag,caller\n"
+				  "  Detect post-free cache corruptions: -dMno-merge,cold-first,integrity,caller\n",
+			          *err);
+			return -1;
+		}
+
+		for (v = 0; dbg_options[v].flg; v++) {
+			if (isteq(feat, ist(dbg_options[v].set))) {
+				new_dbg |= dbg_options[v].flg;
+				/* UAF implicitly disables caching, but it's
+				 * still possible to forcefully re-enable it.
+				 */
+				if (dbg_options[v].flg == POOL_DBG_UAF)
+					new_dbg |= POOL_DBG_NO_CACHE;
+				/* fail should preset the tune.fail-alloc ratio to 1%  */
+				if (dbg_options[v].flg == POOL_DBG_FAIL_ALLOC)
+					mem_fail_rate = 1;
+				break;
+			}
+			else if (isteq(feat, ist(dbg_options[v].clr))) {
+				new_dbg &= ~dbg_options[v].flg;
+				/* no-fail should reset the tune.fail-alloc ratio */
+				if (dbg_options[v].flg == POOL_DBG_FAIL_ALLOC)
+					mem_fail_rate = 0;
+				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;
+}
+
+/* parse a "show pools" command. It returns 1 on failure, 0 if it starts to dump. */
+static int cli_parse_show_pools(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	struct show_pools_ctx *ctx = applet_reserve_svcctx(appctx, sizeof(*ctx));
+	int arg;
+
+	for (arg = 2; *args[arg]; arg++) {
+		if (strcmp(args[arg], "byname") == 0) {
+			ctx->by_what = 1; // sort output by name
+		}
+		else if (strcmp(args[arg], "bysize") == 0) {
+			ctx->by_what = 2; // sort output by item size
+		}
+		else if (strcmp(args[arg], "byusage") == 0) {
+			ctx->by_what = 3; // sort output by total allocated size
+		}
+		else if (strcmp(args[arg], "match") == 0 && *args[arg+1]) {
+			ctx->prefix = strdup(args[arg+1]); // only pools starting with this
+			arg++;
+		}
+		else if (isdigit((unsigned char)*args[arg])) {
+			ctx->maxcnt = atoi(args[arg]); // number of entries to dump
+		}
+		else
+			return cli_err(appctx, "Expects either 'byname', 'bysize', 'byusage', 'match <pfx>', or a max number of output lines.\n");
+	}
+	return 0;
+}
+
+/* release the "show pools" context */
+static void cli_release_show_pools(struct appctx *appctx)
+{
+	struct show_pools_ctx *ctx = appctx->svcctx;
+
+	ha_free(&ctx->prefix);
+}
+
+/* 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)
+{
+	struct show_pools_ctx *ctx = appctx->svcctx;
+
+	dump_pools_to_trash(ctx->by_what, ctx->maxcnt, ctx->prefix);
+	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 (!using_default_allocator) {
+		char *ptr = NULL;
+		memprintf(&ptr, "Running with a replaced memory allocator (e.g. via LD_PRELOAD).");
+		hap_register_build_opts(ptr, 1);
+		mark_tainted(TAINTED_REPLACED_MEM_ALLOCATOR);
+	}
+}
+INITCALL0(STG_REGISTER, pools_register_build_options);
+
+/* register cli keywords */
+static struct cli_kw_list cli_kws = {{ },{
+	{ { "show", "pools",  NULL }, "show pools [by*] [match <pfx>] [nb]     : report information about the memory pools usage", cli_parse_show_pools, cli_io_handler_dump_pools, cli_release_show_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 "tune.memory.hot-size" */
+static int mem_parse_global_hot_size(char **args, int section_type, struct proxy *curpx,
+                                       const struct proxy *defpx, const char *file, int line,
+                                       char **err)
+{
+	long size;
+
+	if (too_many_args(1, args, err, NULL))
+		return -1;
+
+	size = atol(args[1]);
+	if (size <= 0) {
+	    memprintf(err, "'%s' expects a strictly positive value.", args[0]);
+	    return -1;
+	}
+
+	global.tune.pool_cache_size = size;
+	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, "tune.memory.hot-size", mem_parse_global_hot_size },
+	{ 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:
+ */