blob: 834a9446c16fab3c1663547ecbab5f630327daa1 [file] [log] [blame]
#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;
}