lihao/jemalloc
1
0
Fork 0
mirror of https://github.com/jemalloc/jemalloc.git synced 2026-07-23 21:23:06 +00:00
Code Issues Packages Projects Releases Wiki Activity

Drop high rank locks when creating threads.

Browse Source 
Avoid holding arenas_lock and background_thread_lock when creating background
threads, because pthread_create may take internal locks, and potentially cause
deadlock with jemalloc internal locks.
This commit is contained in:
Qi Wang
2017-06-07 15:49:09 -07:00
committed by Qi Wang
parent 00869e39a3
commit 73713fbb27
5 changed files with 43 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

36
src/jemalloc.c
View File

@@ -70,7 +70,7 @@ unsigned opt_narenas = 0;
unsigned ncpus;
/* Protects arenas initialization. */
static malloc_mutex_t arenas_lock;
malloc_mutex_t arenas_lock;
/*
* Arenas that are used to service external requests. Not all elements of the
* arenas array are necessarily used; arenas are created lazily as needed.
@@ -335,6 +335,25 @@ arena_init_locked(tsdn_t *tsdn, unsigned ind, extent_hooks_t *extent_hooks) {
return arena;
}
static void
arena_new_create_background_thread(tsdn_t *tsdn, unsigned ind) {
if (ind == 0) {
return;
}
/* background_thread_create() handles reentrancy internally. */
if (have_background_thread) {
bool err;
malloc_mutex_lock(tsdn, &background_thread_lock);
err = background_thread_create(tsdn_tsd(tsdn), ind);
malloc_mutex_unlock(tsdn, &background_thread_lock);
if (err) {
malloc_printf("<jemalloc>: error in background thread "
"creation for arena %u. Abort.\n", ind);
abort();
}
}
}
arena_t *
arena_init(tsdn_t *tsdn, unsigned ind, extent_hooks_t *extent_hooks) {
arena_t *arena;
@@ -342,6 +361,9 @@ arena_init(tsdn_t *tsdn, unsigned ind, extent_hooks_t *extent_hooks) {
malloc_mutex_lock(tsdn, &arenas_lock);
arena = arena_init_locked(tsdn, ind, extent_hooks);
malloc_mutex_unlock(tsdn, &arenas_lock);
arena_new_create_background_thread(tsdn, ind);
return arena;
}
@@ -475,6 +497,7 @@ arena_choose_hard(tsd_t *tsd, bool internal) {
if (narenas_auto > 1) {
unsigned i, j, choose[2], first_null;
bool is_new_arena[2];
/*
* Determine binding for both non-internal and internal
@@ -486,6 +509,7 @@ arena_choose_hard(tsd_t *tsd, bool internal) {
for (j = 0; j < 2; j++) {
choose[j] = 0;
is_new_arena[j] = false;
}
first_null = narenas_auto;
@@ -545,6 +569,7 @@ arena_choose_hard(tsd_t *tsd, bool internal) {
&arenas_lock);
return NULL;
}
is_new_arena[j] = true;
if (!!j == internal) {
ret = arena;
}
@@ -552,6 +577,15 @@ arena_choose_hard(tsd_t *tsd, bool internal) {
arena_bind(tsd, choose[j], !!j);
}
malloc_mutex_unlock(tsd_tsdn(tsd), &arenas_lock);
for (j = 0; j < 2; j++) {
if (is_new_arena[j]) {
assert(choose[j] > 0);
arena_new_create_background_thread(
tsd_tsdn(tsd), choose[j]);
}
}
} else {
ret = arena_get(tsd_tsdn(tsd), 0, false);
arena_bind(tsd, 0, false);