diff options
Diffstat (limited to 'malloc/arena.c')
| -rw-r--r-- | malloc/arena.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/malloc/arena.c b/malloc/arena.c index 8db255966d..a844392a6b 100644 --- a/malloc/arena.c +++ b/malloc/arena.c @@ -210,6 +210,10 @@ free_atfork(Void_t* mem, const Void_t *caller) (void)mutex_unlock(&ar_ptr->mutex); } + +/* Counter for number of times the list is locked by the same thread. */ +static unsigned int atfork_recursive_cntr; + /* The following two functions are registered via thread_atfork() to make sure that the mutexes remain in a consistent state in the fork()ed version of a thread. Also adapt the malloc and free hooks @@ -223,7 +227,18 @@ ptmalloc_lock_all (void) if(__malloc_initialized < 1) return; - (void)mutex_lock(&list_lock); + if (mutex_trylock(&list_lock)) + { + Void_t *my_arena; + tsd_getspecific(arena_key, my_arena); + if (my_arena == ATFORK_ARENA_PTR) + /* This is the same thread which already locks the global list. + Just bump the counter. */ + goto out; + + /* This thread has to wait its turn. */ + (void)mutex_lock(&list_lock); + } for(ar_ptr = &main_arena;;) { (void)mutex_lock(&ar_ptr->mutex); ar_ptr = ar_ptr->next; @@ -236,6 +251,8 @@ ptmalloc_lock_all (void) /* Only the current thread may perform malloc/free calls now. */ tsd_getspecific(arena_key, save_arena); tsd_setspecific(arena_key, ATFORK_ARENA_PTR); + out: + ++atfork_recursive_cntr; } static void @@ -245,6 +262,8 @@ ptmalloc_unlock_all (void) if(__malloc_initialized < 1) return; + if (--atfork_recursive_cntr != 0) + return; tsd_setspecific(arena_key, save_arena); __malloc_hook = save_malloc_hook; __free_hook = save_free_hook; |