#include "jemalloc/internal/jemalloc_preamble.h" #include "jemalloc/internal/jemalloc_internal_includes.h" #include "jemalloc/internal/assert.h" #include "jemalloc/internal/buf_writer.h" #include "jemalloc/internal/emitter.h" #include "jemalloc/internal/prof_data.h" #include "jemalloc/internal/prof_recent.h" ssize_t opt_prof_recent_alloc_max = PROF_RECENT_ALLOC_MAX_DEFAULT; malloc_mutex_t prof_recent_alloc_mtx; /* Protects the fields below */ static atomic_zd_t prof_recent_alloc_max; static ssize_t prof_recent_alloc_count = 0; prof_recent_list_t prof_recent_alloc_list; malloc_mutex_t prof_recent_dump_mtx; /* Protects dumping. */ static void prof_recent_alloc_max_init() { atomic_store_zd(&prof_recent_alloc_max, opt_prof_recent_alloc_max, ATOMIC_RELAXED); } static inline ssize_t prof_recent_alloc_max_get_no_lock() { return atomic_load_zd(&prof_recent_alloc_max, ATOMIC_RELAXED); } static inline ssize_t prof_recent_alloc_max_get(tsd_t *tsd) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); return prof_recent_alloc_max_get_no_lock(); } static inline ssize_t prof_recent_alloc_max_update(tsd_t *tsd, ssize_t max) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); ssize_t old_max = prof_recent_alloc_max_get(tsd); atomic_store_zd(&prof_recent_alloc_max, max, ATOMIC_RELAXED); return old_max; } static prof_recent_t * prof_recent_allocate_node(tsdn_t *tsdn) { return (prof_recent_t *)iallocztm(tsdn, sizeof(prof_recent_t), sz_size2index(sizeof(prof_recent_t)), false, NULL, true, arena_get(tsdn, 0, false), true); } static void prof_recent_free_node(tsdn_t *tsdn, prof_recent_t *node) { assert(node != NULL); assert(isalloc(tsdn, node) == sz_s2u(sizeof(prof_recent_t))); idalloctm(tsdn, node, NULL, NULL, true, true); } static inline void increment_recent_count(tsd_t *tsd, prof_tctx_t *tctx) { malloc_mutex_assert_owner(tsd_tsdn(tsd), tctx->tdata->lock); ++tctx->recent_count; assert(tctx->recent_count > 0); } bool prof_recent_alloc_prepare(tsd_t *tsd, prof_tctx_t *tctx) { cassert(config_prof); assert(opt_prof && prof_booted); malloc_mutex_assert_owner(tsd_tsdn(tsd), tctx->tdata->lock); malloc_mutex_assert_not_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); /* * Check whether last-N mode is turned on without trying to acquire the * lock, so as to optimize for the following two scenarios: * (1) Last-N mode is switched off; * (2) Dumping, during which last-N mode is temporarily turned off so * as not to block sampled allocations. */ if (prof_recent_alloc_max_get_no_lock() == 0) { return false; } /* * Increment recent_count to hold the tctx so that it won't be gone * even after tctx->tdata->lock is released. This acts as a * "placeholder"; the real recording of the allocation requires a lock * on prof_recent_alloc_mtx and is done in prof_recent_alloc (when * tctx->tdata->lock has been released). */ increment_recent_count(tsd, tctx); return true; } static void decrement_recent_count(tsd_t *tsd, prof_tctx_t *tctx) { malloc_mutex_assert_not_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); assert(tctx != NULL); malloc_mutex_lock(tsd_tsdn(tsd), tctx->tdata->lock); assert(tctx->recent_count > 0); --tctx->recent_count; prof_tctx_try_destroy(tsd, tctx); } static inline edata_t * prof_recent_alloc_edata_get_no_lock(const prof_recent_t *n) { return (edata_t *)atomic_load_p(&n->alloc_edata, ATOMIC_ACQUIRE); } edata_t * prof_recent_alloc_edata_get_no_lock_test(const prof_recent_t *n) { cassert(config_prof); return prof_recent_alloc_edata_get_no_lock(n); } static inline edata_t * prof_recent_alloc_edata_get(tsd_t *tsd, const prof_recent_t *n) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); return prof_recent_alloc_edata_get_no_lock(n); } static void prof_recent_alloc_edata_set(tsd_t *tsd, prof_recent_t *n, edata_t *edata) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); atomic_store_p(&n->alloc_edata, edata, ATOMIC_RELEASE); } void edata_prof_recent_alloc_init(edata_t *edata) { cassert(config_prof); edata_prof_recent_alloc_set_dont_call_directly(edata, NULL); } static inline prof_recent_t * edata_prof_recent_alloc_get_no_lock(const edata_t *edata) { cassert(config_prof); return edata_prof_recent_alloc_get_dont_call_directly(edata); } prof_recent_t * edata_prof_recent_alloc_get_no_lock_test(const edata_t *edata) { cassert(config_prof); return edata_prof_recent_alloc_get_no_lock(edata); } static inline prof_recent_t * edata_prof_recent_alloc_get(tsd_t *tsd, const edata_t *edata) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); prof_recent_t *recent_alloc = edata_prof_recent_alloc_get_no_lock(edata); assert(recent_alloc == NULL || prof_recent_alloc_edata_get(tsd, recent_alloc) == edata); return recent_alloc; } static prof_recent_t * edata_prof_recent_alloc_update_internal(tsd_t *tsd, edata_t *edata, prof_recent_t *recent_alloc) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); prof_recent_t *old_recent_alloc = edata_prof_recent_alloc_get(tsd, edata); edata_prof_recent_alloc_set_dont_call_directly(edata, recent_alloc); return old_recent_alloc; } static void edata_prof_recent_alloc_set(tsd_t *tsd, edata_t *edata, prof_recent_t *recent_alloc) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); assert(recent_alloc != NULL); prof_recent_t *old_recent_alloc = edata_prof_recent_alloc_update_internal(tsd, edata, recent_alloc); assert(old_recent_alloc == NULL); prof_recent_alloc_edata_set(tsd, recent_alloc, edata); } static void edata_prof_recent_alloc_reset(tsd_t *tsd, edata_t *edata, prof_recent_t *recent_alloc) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); assert(recent_alloc != NULL); prof_recent_t *old_recent_alloc = edata_prof_recent_alloc_update_internal(tsd, edata, NULL); assert(old_recent_alloc == recent_alloc); assert(edata == prof_recent_alloc_edata_get(tsd, recent_alloc)); prof_recent_alloc_edata_set(tsd, recent_alloc, NULL); } /* * This function should be called right before an allocation is released, so * that the associated recent allocation record can contain the following * information: * (1) The allocation is released; * (2) The time of the deallocation; and * (3) The prof_tctx associated with the deallocation. */ void prof_recent_alloc_reset(tsd_t *tsd, edata_t *edata) { cassert(config_prof); /* * Check whether the recent allocation record still exists without * trying to acquire the lock. */ if (edata_prof_recent_alloc_get_no_lock(edata) == NULL) { return; } prof_tctx_t *dalloc_tctx = prof_tctx_create(tsd); /* * In case dalloc_tctx is NULL, e.g. due to OOM, we will not record the * deallocation time / tctx, which is handled later, after we check * again when holding the lock. */ if (dalloc_tctx != NULL) { malloc_mutex_lock(tsd_tsdn(tsd), dalloc_tctx->tdata->lock); increment_recent_count(tsd, dalloc_tctx); dalloc_tctx->prepared = false; malloc_mutex_unlock(tsd_tsdn(tsd), dalloc_tctx->tdata->lock); } malloc_mutex_lock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); /* Check again after acquiring the lock. */ prof_recent_t *recent = edata_prof_recent_alloc_get(tsd, edata); if (recent != NULL) { assert(nstime_equals_zero(&recent->dalloc_time)); assert(recent->dalloc_tctx == NULL); if (dalloc_tctx != NULL) { nstime_prof_update(&recent->dalloc_time); recent->dalloc_tctx = dalloc_tctx; dalloc_tctx = NULL; } edata_prof_recent_alloc_reset(tsd, edata, recent); } malloc_mutex_unlock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); if (dalloc_tctx != NULL) { /* We lost the rase - the allocation record was just gone. */ decrement_recent_count(tsd, dalloc_tctx); } } static void prof_recent_alloc_evict_edata(tsd_t *tsd, prof_recent_t *recent_alloc) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); edata_t *edata = prof_recent_alloc_edata_get(tsd, recent_alloc); if (edata != NULL) { edata_prof_recent_alloc_reset(tsd, edata, recent_alloc); } } static bool prof_recent_alloc_is_empty(tsd_t *tsd) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); if (ql_empty(&prof_recent_alloc_list)) { assert(prof_recent_alloc_count == 0); return true; } else { assert(prof_recent_alloc_count > 0); return false; } } static void prof_recent_alloc_assert_count(tsd_t *tsd) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); if (!config_debug) { return; } ssize_t count = 0; prof_recent_t *n; ql_foreach(n, &prof_recent_alloc_list, link) { ++count; } assert(count == prof_recent_alloc_count); assert(prof_recent_alloc_max_get(tsd) == -1 || count <= prof_recent_alloc_max_get(tsd)); } void prof_recent_alloc(tsd_t *tsd, edata_t *edata, size_t size, size_t usize) { cassert(config_prof); assert(edata != NULL); prof_tctx_t *tctx = edata_prof_tctx_get(edata); malloc_mutex_assert_not_owner(tsd_tsdn(tsd), tctx->tdata->lock); malloc_mutex_lock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); prof_recent_alloc_assert_count(tsd); /* * Reserve a new prof_recent_t node if needed. If needed, we release * the prof_recent_alloc_mtx lock and allocate. Then, rather than * immediately checking for OOM, we regain the lock and try to make use * of the reserve node if needed. There are six scenarios: * * \ now | no need | need but OOMed | need and allocated * later \ | | | * ------------------------------------------------------------ * no need | (1) | (2) | (3) * ------------------------------------------------------------ * need | (4) | (5) | (6) * * First, "(4)" never happens, because we don't release the lock in the * middle if there's no need for a new node; in such cases "(1)" always * takes place, which is trivial. * * Out of the remaining four scenarios, "(6)" is the common case and is * trivial. "(5)" is also trivial, in which case we'll rollback the * effect of prof_recent_alloc_prepare() as expected. * * "(2)" / "(3)" occurs when the need for a new node is gone after we * regain the lock. If the new node is successfully allocated, i.e. in * the case of "(3)", we'll release it in the end; otherwise, i.e. in * the case of "(2)", we do nothing - we're lucky that the OOM ends up * doing no harm at all. * * Therefore, the only performance cost of the "release lock" -> * "allocate" -> "regain lock" design is the "(3)" case, but it happens * very rarely, so the cost is relatively small compared to the gain of * not having to have the lock order of prof_recent_alloc_mtx above all * the allocation locks. */ prof_recent_t *reserve = NULL; if (prof_recent_alloc_max_get(tsd) == -1 || prof_recent_alloc_count < prof_recent_alloc_max_get(tsd)) { assert(prof_recent_alloc_max_get(tsd) != 0); malloc_mutex_unlock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); reserve = prof_recent_allocate_node(tsd_tsdn(tsd)); malloc_mutex_lock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); prof_recent_alloc_assert_count(tsd); } if (prof_recent_alloc_max_get(tsd) == 0) { assert(prof_recent_alloc_is_empty(tsd)); goto label_rollback; } prof_tctx_t *old_alloc_tctx, *old_dalloc_tctx; if (prof_recent_alloc_count == prof_recent_alloc_max_get(tsd)) { /* If upper limit is reached, rotate the head. */ assert(prof_recent_alloc_max_get(tsd) != -1); assert(!prof_recent_alloc_is_empty(tsd)); prof_recent_t *head = ql_first(&prof_recent_alloc_list); old_alloc_tctx = head->alloc_tctx; assert(old_alloc_tctx != NULL); old_dalloc_tctx = head->dalloc_tctx; prof_recent_alloc_evict_edata(tsd, head); ql_rotate(&prof_recent_alloc_list, link); } else { /* Otherwise make use of the new node. */ assert(prof_recent_alloc_max_get(tsd) == -1 || prof_recent_alloc_count < prof_recent_alloc_max_get(tsd)); if (reserve == NULL) { goto label_rollback; } ql_elm_new(reserve, link); ql_tail_insert(&prof_recent_alloc_list, reserve, link); reserve = NULL; old_alloc_tctx = NULL; old_dalloc_tctx = NULL; ++prof_recent_alloc_count; } /* Fill content into the tail node. */ prof_recent_t *tail = ql_last(&prof_recent_alloc_list, link); assert(tail != NULL); tail->size = size; tail->usize = usize; nstime_copy(&tail->alloc_time, edata_prof_alloc_time_get(edata)); tail->alloc_tctx = tctx; nstime_init_zero(&tail->dalloc_time); tail->dalloc_tctx = NULL; edata_prof_recent_alloc_set(tsd, edata, tail); assert(!prof_recent_alloc_is_empty(tsd)); prof_recent_alloc_assert_count(tsd); malloc_mutex_unlock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); if (reserve != NULL) { prof_recent_free_node(tsd_tsdn(tsd), reserve); } /* * Asynchronously handle the tctx of the old node, so that there's no * simultaneous holdings of prof_recent_alloc_mtx and tdata->lock. * In the worst case this may delay the tctx release but it's better * than holding prof_recent_alloc_mtx for longer. */ if (old_alloc_tctx != NULL) { decrement_recent_count(tsd, old_alloc_tctx); } if (old_dalloc_tctx != NULL) { decrement_recent_count(tsd, old_dalloc_tctx); } return; label_rollback: assert(edata_prof_recent_alloc_get(tsd, edata) == NULL); prof_recent_alloc_assert_count(tsd); malloc_mutex_unlock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); if (reserve != NULL) { prof_recent_free_node(tsd_tsdn(tsd), reserve); } decrement_recent_count(tsd, tctx); } ssize_t prof_recent_alloc_max_ctl_read() { cassert(config_prof); /* Don't bother to acquire the lock. */ return prof_recent_alloc_max_get_no_lock(); } static void prof_recent_alloc_restore_locked(tsd_t *tsd, prof_recent_list_t *to_delete) { malloc_mutex_assert_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); ssize_t max = prof_recent_alloc_max_get(tsd); if (max == -1 || prof_recent_alloc_count <= max) { /* Easy case - no need to alter the list. */ ql_new(to_delete); prof_recent_alloc_assert_count(tsd); return; } prof_recent_t *node; ql_foreach(node, &prof_recent_alloc_list, link) { if (prof_recent_alloc_count == max) { break; } prof_recent_alloc_evict_edata(tsd, node); --prof_recent_alloc_count; } assert(prof_recent_alloc_count == max); ql_move(to_delete, &prof_recent_alloc_list); if (max == 0) { assert(node == NULL); } else { assert(node != NULL); ql_split(to_delete, node, &prof_recent_alloc_list, link); } assert(!ql_empty(to_delete)); prof_recent_alloc_assert_count(tsd); } static void prof_recent_alloc_async_cleanup(tsd_t *tsd, prof_recent_list_t *to_delete) { malloc_mutex_assert_not_owner(tsd_tsdn(tsd), &prof_recent_dump_mtx); malloc_mutex_assert_not_owner(tsd_tsdn(tsd), &prof_recent_alloc_mtx); while (!ql_empty(to_delete)) { prof_recent_t *node = ql_first(to_delete); ql_remove(to_delete, node, link); decrement_recent_count(tsd, node->alloc_tctx); if (node->dalloc_tctx != NULL) { decrement_recent_count(tsd, node->dalloc_tctx); } prof_recent_free_node(tsd_tsdn(tsd), node); } } ssize_t prof_recent_alloc_max_ctl_write(tsd_t *tsd, ssize_t max) { cassert(config_prof); assert(max >= -1); malloc_mutex_lock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); prof_recent_alloc_assert_count(tsd); const ssize_t old_max = prof_recent_alloc_max_update(tsd, max); prof_recent_list_t to_delete; prof_recent_alloc_restore_locked(tsd, &to_delete); malloc_mutex_unlock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); prof_recent_alloc_async_cleanup(tsd, &to_delete); return old_max; } static void prof_recent_alloc_dump_bt(emitter_t *emitter, prof_tctx_t *tctx) { char bt_buf[2 * sizeof(intptr_t) + 3]; char *s = bt_buf; assert(tctx != NULL); prof_bt_t *bt = &tctx->gctx->bt; for (size_t i = 0; i < bt->len; ++i) { malloc_snprintf(bt_buf, sizeof(bt_buf), "%p", bt->vec[i]); emitter_json_value(emitter, emitter_type_string, &s); } } static void prof_recent_alloc_dump_node(emitter_t *emitter, prof_recent_t *node) { emitter_json_object_begin(emitter); emitter_json_kv(emitter, "size", emitter_type_size, &node->size); emitter_json_kv(emitter, "usize", emitter_type_size, &node->usize); bool released = prof_recent_alloc_edata_get_no_lock(node) == NULL; emitter_json_kv(emitter, "released", emitter_type_bool, &released); emitter_json_kv(emitter, "alloc_thread_uid", emitter_type_uint64, &node->alloc_tctx->thr_uid); prof_tdata_t *alloc_tdata = node->alloc_tctx->tdata; assert(alloc_tdata != NULL); if (alloc_tdata->thread_name != NULL) { emitter_json_kv(emitter, "alloc_thread_name", emitter_type_string, &alloc_tdata->thread_name); } uint64_t alloc_time_ns = nstime_ns(&node->alloc_time); emitter_json_kv(emitter, "alloc_time", emitter_type_uint64, &alloc_time_ns); emitter_json_array_kv_begin(emitter, "alloc_trace"); prof_recent_alloc_dump_bt(emitter, node->alloc_tctx); emitter_json_array_end(emitter); if (released && node->dalloc_tctx != NULL) { emitter_json_kv(emitter, "dalloc_thread_uid", emitter_type_uint64, &node->dalloc_tctx->thr_uid); prof_tdata_t *dalloc_tdata = node->dalloc_tctx->tdata; assert(dalloc_tdata != NULL); if (dalloc_tdata->thread_name != NULL) { emitter_json_kv(emitter, "dalloc_thread_name", emitter_type_string, &dalloc_tdata->thread_name); } assert(!nstime_equals_zero(&node->dalloc_time)); uint64_t dalloc_time_ns = nstime_ns(&node->dalloc_time); emitter_json_kv(emitter, "dalloc_time", emitter_type_uint64, &dalloc_time_ns); emitter_json_array_kv_begin(emitter, "dalloc_trace"); prof_recent_alloc_dump_bt(emitter, node->dalloc_tctx); emitter_json_array_end(emitter); } emitter_json_object_end(emitter); } #define PROF_RECENT_PRINT_BUFSIZE 65536 JEMALLOC_COLD void prof_recent_alloc_dump(tsd_t *tsd, write_cb_t *write_cb, void *cbopaque) { cassert(config_prof); malloc_mutex_lock(tsd_tsdn(tsd), &prof_recent_dump_mtx); buf_writer_t buf_writer; buf_writer_init(tsd_tsdn(tsd), &buf_writer, write_cb, cbopaque, NULL, PROF_RECENT_PRINT_BUFSIZE); emitter_t emitter; emitter_init(&emitter, emitter_output_json_compact, buf_writer_cb, &buf_writer); prof_recent_list_t temp_list; malloc_mutex_lock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); prof_recent_alloc_assert_count(tsd); ssize_t dump_max = prof_recent_alloc_max_get(tsd); ql_move(&temp_list, &prof_recent_alloc_list); ssize_t dump_count = prof_recent_alloc_count; prof_recent_alloc_count = 0; prof_recent_alloc_assert_count(tsd); malloc_mutex_unlock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); emitter_begin(&emitter); uint64_t sample_interval = (uint64_t)1U << lg_prof_sample; emitter_json_kv(&emitter, "sample_interval", emitter_type_uint64, &sample_interval); emitter_json_kv(&emitter, "recent_alloc_max", emitter_type_ssize, &dump_max); emitter_json_array_kv_begin(&emitter, "recent_alloc"); prof_recent_t *node; ql_foreach(node, &temp_list, link) { prof_recent_alloc_dump_node(&emitter, node); } emitter_json_array_end(&emitter); emitter_end(&emitter); malloc_mutex_lock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); prof_recent_alloc_assert_count(tsd); ql_concat(&temp_list, &prof_recent_alloc_list, link); ql_move(&prof_recent_alloc_list, &temp_list); prof_recent_alloc_count += dump_count; prof_recent_alloc_restore_locked(tsd, &temp_list); malloc_mutex_unlock(tsd_tsdn(tsd), &prof_recent_alloc_mtx); buf_writer_terminate(tsd_tsdn(tsd), &buf_writer); malloc_mutex_unlock(tsd_tsdn(tsd), &prof_recent_dump_mtx); prof_recent_alloc_async_cleanup(tsd, &temp_list); } #undef PROF_RECENT_PRINT_BUFSIZE bool prof_recent_init() { cassert(config_prof); prof_recent_alloc_max_init(); if (malloc_mutex_init(&prof_recent_alloc_mtx, "prof_recent_alloc", WITNESS_RANK_PROF_RECENT_ALLOC, malloc_mutex_rank_exclusive)) { return true; } if (malloc_mutex_init(&prof_recent_dump_mtx, "prof_recent_dump", WITNESS_RANK_PROF_RECENT_DUMP, malloc_mutex_rank_exclusive)) { return true; } ql_new(&prof_recent_alloc_list); return false; }