/* * Memory management functions. * * Copyright 2000-2007 Willy Tarreau * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* 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 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 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 's fill_pattern and fills the free area after with it, * up to 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 items from the end of the local pool cache for * 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 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 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 from the shared one for 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 to the shared cache, which contains * 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 . */ 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(). 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 taken from the pool or * dynamically allocated. In the first case, is updated to point to * the next element in the list. 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. 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 is non-zero, and limit the * number of output lines if is non-zero. It may limit only to * pools whose names start with if 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 , -1 with a help message in , or -2 with * the first error in return the first error in . 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 ', 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 of size and store the * resulting pointer into . 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 ] [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: */