2015-10-16 Florian Weimer <fweimer@redhat.com>
malloc: Rewrite with explicit TLS access using __thread.
* sysdeps/generic/malloc-machine.h (tsd_key_t, tsd_key_create)
(tsd_setspecific, tsd_getspecific): Remove.
* sysdeps/mach/hurd/malloc-machine.h (tsd_key_t, tsd_key_create)
(tsd_setspecific, tsd_getspecific): Likewise.
* sysdeps/nptl/malloc-machine.h (tsd_key_t, tsd_key_create)
(tsd_setspecific, tsd_getspecific): Likewise.
* malloc/arena.c (thread_arena): New TLS variable.
(arena_key): Remove variable.
(arena_get): Use thread_arena.
(arena_lookup): Remove macro.
(malloc_atfork, free_atfork, ptmalloc_lock_all)
(ptmalloc_unlock_all, ptmalloc_unlock_all2, ptmalloc_init)
(_int_new_arena, get_free_list, reused_arena)
(arena_thread_freeres): Use thread_arena.
* manual/memory.texi (Basic Allocation): Remove arena_lookup,
tsd_getspecific, tsd_setspecific from safety annotations.
(Allocating Cleared Space): Remove arena_lookup from safety
annotations.
@@ -64,9 +64,12 @@ extern int sanity_check_heap_info_alignment[(sizeof (heap_info)
+ 2 * SIZE_SZ) % MALLOC_ALIGNMENT
? -1 : 1];
-/* Thread specific data */
+/* Thread specific data. */
+
+static __thread mstate thread_arena attribute_tls_model_ie;
+
+/* Arena free list. */
-static tsd_key_t arena_key;
static mutex_t list_lock = MUTEX_INITIALIZER;
static size_t narenas = 1;
static mstate free_list;
@@ -89,15 +92,10 @@ int __malloc_initialized = -1;
in the new arena. */
#define arena_get(ptr, size) do { \
- arena_lookup (ptr); \
+ ptr = thread_arena; \
arena_lock (ptr, size); \
} while (0)
-#define arena_lookup(ptr) do { \
- void *vptr = NULL; \
- ptr = (mstate) tsd_getspecific (arena_key, vptr); \
- } while (0)
-
#define arena_lock(ptr, size) do { \
if (ptr && !arena_is_corrupt (ptr)) \
(void) mutex_lock (&ptr->mutex); \
@@ -138,11 +136,9 @@ ATFORK_MEM;
static void *
malloc_atfork (size_t sz, const void *caller)
{
- void *vptr = NULL;
void *victim;
- tsd_getspecific (arena_key, vptr);
- if (vptr == ATFORK_ARENA_PTR)
+ if (thread_arena == ATFORK_ARENA_PTR)
{
/* We are the only thread that may allocate at all. */
if (save_malloc_hook != malloc_check)
@@ -172,7 +168,6 @@ malloc_atfork (size_t sz, const void *caller)
static void
free_atfork (void *mem, const void *caller)
{
- void *vptr = NULL;
mstate ar_ptr;
mchunkptr p; /* chunk corresponding to mem */
@@ -188,8 +183,7 @@ free_atfork (void *mem, const void *caller)
}
ar_ptr = arena_for_chunk (p);
- tsd_getspecific (arena_key, vptr);
- _int_free (ar_ptr, p, vptr == ATFORK_ARENA_PTR);
+ _int_free (ar_ptr, p, thread_arena == ATFORK_ARENA_PTR);
}
@@ -212,9 +206,7 @@ ptmalloc_lock_all (void)
if (mutex_trylock (&list_lock))
{
- void *my_arena;
- tsd_getspecific (arena_key, my_arena);
- if (my_arena == ATFORK_ARENA_PTR)
+ if (thread_arena == ATFORK_ARENA_PTR)
/* This is the same thread which already locks the global list.
Just bump the counter. */
goto out;
@@ -234,8 +226,8 @@ ptmalloc_lock_all (void)
__malloc_hook = malloc_atfork;
__free_hook = free_atfork;
/* Only the current thread may perform malloc/free calls now. */
- tsd_getspecific (arena_key, save_arena);
- tsd_setspecific (arena_key, ATFORK_ARENA_PTR);
+ save_arena = thread_arena;
+ thread_arena = ATFORK_ARENA_PTR;
out:
++atfork_recursive_cntr;
}
@@ -251,7 +243,7 @@ ptmalloc_unlock_all (void)
if (--atfork_recursive_cntr != 0)
return;
- tsd_setspecific (arena_key, save_arena);
+ thread_arena = save_arena;
__malloc_hook = save_malloc_hook;
__free_hook = save_free_hook;
for (ar_ptr = &main_arena;; )
@@ -279,7 +271,7 @@ ptmalloc_unlock_all2 (void)
if (__malloc_initialized < 1)
return;
- tsd_setspecific (arena_key, save_arena);
+ thread_arena = save_arena;
__malloc_hook = save_malloc_hook;
__free_hook = save_free_hook;
free_list = NULL;
@@ -372,8 +364,7 @@ ptmalloc_init (void)
__morecore = __failing_morecore;
#endif
- tsd_key_create (&arena_key, NULL);
- tsd_setspecific (arena_key, (void *) &main_arena);
+ thread_arena = &main_arena;
thread_atfork (ptmalloc_lock_all, ptmalloc_unlock_all, ptmalloc_unlock_all2);
const char *s = NULL;
if (__glibc_likely (_environ != NULL))
@@ -761,7 +752,7 @@ _int_new_arena (size_t size)
set_head (top (a), (((char *) h + h->size) - ptr) | PREV_INUSE);
LIBC_PROBE (memory_arena_new, 2, a, size);
- tsd_setspecific (arena_key, (void *) a);
+ thread_arena = a;
mutex_init (&a->mutex);
(void) mutex_lock (&a->mutex);
@@ -794,7 +785,7 @@ get_free_list (void)
{
LIBC_PROBE (memory_arena_reuse_free_list, 1, result);
(void) mutex_lock (&result->mutex);
- tsd_setspecific (arena_key, (void *) result);
+ thread_arena = result;
}
}
@@ -847,7 +838,7 @@ reused_arena (mstate avoid_arena)
out:
LIBC_PROBE (memory_arena_reuse, 2, result, avoid_arena);
- tsd_setspecific (arena_key, (void *) result);
+ thread_arena = result;
next_to_use = result->next;
return result;
@@ -934,9 +925,8 @@ arena_get_retry (mstate ar_ptr, size_t bytes)
static void __attribute__ ((section ("__libc_thread_freeres_fn")))
arena_thread_freeres (void)
{
- void *vptr = NULL;
- mstate a = tsd_getspecific (arena_key, vptr);
- tsd_setspecific (arena_key, NULL);
+ mstate a = thread_arena;
+ thread_arena = NULL;
if (a != NULL)
{
@@ -332,8 +332,6 @@ this function is in @file{stdlib.h}.
@c __libc_malloc @asulock @aculock @acsfd @acsmem
@c force_reg ok
@c *malloc_hook unguarded
-@c arena_lookup ok
-@c tsd_getspecific ok, TLS
@c arena_lock @asulock @aculock @acsfd @acsmem
@c mutex_lock @asulock @aculock
@c arena_get2 @asulock @aculock @acsfd @acsmem
@@ -341,7 +339,6 @@ this function is in @file{stdlib.h}.
@c mutex_lock (list_lock) dup @asulock @aculock
@c mutex_unlock (list_lock) dup @aculock
@c mutex_lock (arena lock) dup @asulock @aculock [returns locked]
-@c tsd_setspecific ok, TLS
@c __get_nprocs ext ok @acsfd
@c NARENAS_FROM_NCORES ok
@c catomic_compare_and_exchange_bool_acq ok
@@ -835,7 +832,6 @@ is declared in @file{stdlib.h}.
@c *__malloc_hook dup unguarded
@c memset dup ok
@c arena_get @asulock @aculock @acsfd @acsmem
-@c arena_lookup dup ok
@c arena_lock dup @asulock @aculock @acsfd @acsmem
@c top dup ok
@c chunksize dup ok
@@ -40,13 +40,6 @@ typedef int mutex_t;
# define mutex_unlock(m) (*(m) = 0)
# define MUTEX_INITIALIZER (0)
-typedef void *tsd_key_t;
-# define tsd_key_create(key, destr) do {} while(0)
-# define tsd_setspecific(key, data) ((key) = (data))
-# define tsd_getspecific(key, vptr) (vptr = (key))
-
-# define thread_atfork(prepare, parent, child) do {} while(0)
-
#endif /* !defined mutex_init */
#ifndef atomic_full_barrier
@@ -52,16 +52,6 @@
/* No we're *not* using pthreads. */
#define __pthread_initialize ((void (*)(void))0)
-/* thread specific data for glibc */
-
-#include <libc-tsd.h>
-
-typedef int tsd_key_t[1]; /* no key data structure, libc magic does it */
-__libc_tsd_define (static, void *, MALLOC) /* declaration/common definition */
-#define tsd_key_create(key, destr) ((void) (key))
-#define tsd_setspecific(key, data) __libc_tsd_set (void *, MALLOC, (data))
-#define tsd_getspecific(key, vptr) ((vptr) = __libc_tsd_get (void *, MALLOC))
-
/* madvise is a stub on Hurd, so don't bother calling it. */
#include <sys/mman.h>
@@ -58,16 +58,6 @@ extern void *__dso_handle __attribute__ ((__weak__));
__linkin_atfork (&atfork_mem)
#endif
-/* thread specific data for glibc */
-
-#include <libc-tsd.h>
-
-typedef int tsd_key_t[1]; /* no key data structure, libc magic does it */
-__libc_tsd_define (static, void *, MALLOC) /* declaration/common definition */
-#define tsd_key_create(key, destr) ((void) (key))
-#define tsd_setspecific(key, data) __libc_tsd_set (void *, MALLOC, (data))
-#define tsd_getspecific(key, vptr) ((vptr) = __libc_tsd_get (void *, MALLOC))
-
#include <sysdeps/generic/malloc-machine.h>
#endif /* !defined(_MALLOC_MACHINE_H) */