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-rw-r--r--malloc/arena.c125
-rw-r--r--malloc/malloc.c2
2 files changed, 8 insertions, 119 deletions
diff --git a/malloc/arena.c b/malloc/arena.c
index bba83e9..8bf8171 100644
--- a/malloc/arena.c
+++ b/malloc/arena.c
@@ -129,75 +129,6 @@ int __malloc_initialized = -1;
/* atfork support. */
-static void *(*save_malloc_hook)(size_t __size, const void *);
-static void (*save_free_hook) (void *__ptr, const void *);
-static void *save_arena;
-
-/* Magic value for the thread-specific arena pointer when
- malloc_atfork() is in use. */
-
-# define ATFORK_ARENA_PTR ((void *) -1)
-
-/* The following hooks are used while the `atfork' handling mechanism
- is active. */
-
-static void *
-malloc_atfork (size_t sz, const void *caller)
-{
- void *victim;
-
- if (thread_arena == ATFORK_ARENA_PTR)
- {
- /* We are the only thread that may allocate at all. */
- if (save_malloc_hook != malloc_check)
- {
- return _int_malloc (&main_arena, sz);
- }
- else
- {
- if (top_check () < 0)
- return 0;
-
- victim = _int_malloc (&main_arena, sz + 1);
- return mem2mem_check (victim, sz);
- }
- }
- else
- {
- /* Suspend the thread until the `atfork' handlers have completed.
- By that time, the hooks will have been reset as well, so that
- mALLOc() can be used again. */
- (void) mutex_lock (&list_lock);
- (void) mutex_unlock (&list_lock);
- return __libc_malloc (sz);
- }
-}
-
-static void
-free_atfork (void *mem, const void *caller)
-{
- mstate ar_ptr;
- mchunkptr p; /* chunk corresponding to mem */
-
- if (mem == 0) /* free(0) has no effect */
- return;
-
- p = mem2chunk (mem); /* do not bother to replicate free_check here */
-
- if (chunk_is_mmapped (p)) /* release mmapped memory. */
- {
- munmap_chunk (p);
- return;
- }
-
- ar_ptr = arena_for_chunk (p);
- _int_free (ar_ptr, p, thread_arena == ATFORK_ARENA_PTR);
-}
-
-
-/* Counter for number of times the list is locked by the same thread. */
-static unsigned int atfork_recursive_cntr;
-
/* The following three functions are called around fork from a
multi-threaded process. We do not use the general fork handler
mechanism to make sure that our handlers are the last ones being
@@ -207,63 +138,30 @@ static unsigned int atfork_recursive_cntr;
void
__malloc_fork_lock_parent (void)
{
- mstate ar_ptr;
-
if (__malloc_initialized < 1)
return;
/* We do not acquire free_list_lock here because we completely
reconstruct free_list in __malloc_fork_unlock_child. */
- if (mutex_trylock (&list_lock))
- {
- if (thread_arena == ATFORK_ARENA_PTR)
- /* This is the same thread which already locks the global list.
- Just bump the counter. */
- goto out;
+ (void) mutex_lock (&list_lock);
- /* This thread has to wait its turn. */
- (void) mutex_lock (&list_lock);
- }
- for (ar_ptr = &main_arena;; )
+ for (mstate ar_ptr = &main_arena;; )
{
(void) mutex_lock (&ar_ptr->mutex);
ar_ptr = ar_ptr->next;
if (ar_ptr == &main_arena)
break;
}
- save_malloc_hook = __malloc_hook;
- save_free_hook = __free_hook;
- __malloc_hook = malloc_atfork;
- __free_hook = free_atfork;
- /* Only the current thread may perform malloc/free calls now.
- save_arena will be reattached to the current thread, in
- __malloc_fork_lock_parent, so save_arena->attached_threads is not
- updated. */
- save_arena = thread_arena;
- thread_arena = ATFORK_ARENA_PTR;
-out:
- ++atfork_recursive_cntr;
}
void
__malloc_fork_unlock_parent (void)
{
- mstate ar_ptr;
-
if (__malloc_initialized < 1)
return;
- if (--atfork_recursive_cntr != 0)
- return;
-
- /* Replace ATFORK_ARENA_PTR with save_arena.
- save_arena->attached_threads was not changed in
- __malloc_fork_lock_parent and is still correct. */
- thread_arena = save_arena;
- __malloc_hook = save_malloc_hook;
- __free_hook = save_free_hook;
- for (ar_ptr = &main_arena;; )
+ for (mstate ar_ptr = &main_arena;; )
{
(void) mutex_unlock (&ar_ptr->mutex);
ar_ptr = ar_ptr->next;
@@ -276,25 +174,19 @@ __malloc_fork_unlock_parent (void)
void
__malloc_fork_unlock_child (void)
{
- mstate ar_ptr;
-
if (__malloc_initialized < 1)
return;
- thread_arena = save_arena;
- __malloc_hook = save_malloc_hook;
- __free_hook = save_free_hook;
-
- /* Push all arenas to the free list, except save_arena, which is
+ /* Push all arenas to the free list, except thread_arena, which is
attached to the current thread. */
mutex_init (&free_list_lock);
- if (save_arena != NULL)
- ((mstate) save_arena)->attached_threads = 1;
+ if (thread_arena != NULL)
+ thread_arena->attached_threads = 1;
free_list = NULL;
- for (ar_ptr = &main_arena;; )
+ for (mstate ar_ptr = &main_arena;; )
{
mutex_init (&ar_ptr->mutex);
- if (ar_ptr != save_arena)
+ if (ar_ptr != thread_arena)
{
/* This arena is no longer attached to any thread. */
ar_ptr->attached_threads = 0;
@@ -307,7 +199,6 @@ __malloc_fork_unlock_child (void)
}
mutex_init (&list_lock);
- atfork_recursive_cntr = 0;
}
/* Initialization routine. */
diff --git a/malloc/malloc.c b/malloc/malloc.c
index 7aad75a..ea97df2 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -1074,8 +1074,6 @@ static void* realloc_check(void* oldmem, size_t bytes,
const void *caller);
static void* memalign_check(size_t alignment, size_t bytes,
const void *caller);
-static void* malloc_atfork(size_t sz, const void *caller);
-static void free_atfork(void* mem, const void *caller);
/* ------------------ MMAP support ------------------ */