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Diffstat (limited to 'libpthread/nptl/pthread_key_create.c')
-rw-r--r--libpthread/nptl/pthread_key_create.c55
1 files changed, 23 insertions, 32 deletions
diff --git a/libpthread/nptl/pthread_key_create.c b/libpthread/nptl/pthread_key_create.c
index 88d160e18..3744c08ad 100644
--- a/libpthread/nptl/pthread_key_create.c
+++ b/libpthread/nptl/pthread_key_create.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003, 2006 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
@@ -19,45 +19,36 @@
#include <errno.h>
#include "pthreadP.h"
+#include <atomic.h>
-/* Internal mutex for __pthread_keys table handling. */
-lll_lock_t __pthread_keys_lock = LLL_LOCK_INITIALIZER;
-
int
__pthread_key_create (
pthread_key_t *key,
void (*destr) (void *))
{
- int result = EAGAIN;
- size_t cnt;
-
- lll_lock (__pthread_keys_lock);
-
/* Find a slot in __pthread_kyes which is unused. */
- for (cnt = 0; cnt < PTHREAD_KEYS_MAX; ++cnt)
- if (KEY_UNUSED (__pthread_keys[cnt].seq)
- && KEY_USABLE (__pthread_keys[cnt].seq))
- {
- /* We found an unused slot. */
- ++__pthread_keys[cnt].seq;
-
- /* Remember the destructor. */
- __pthread_keys[cnt].destr = destr;
-
- /* Return the key to the caller. */
- *key = cnt;
-
- /* The call succeeded. */
- result = 0;
-
- /* We found a key and can stop now. */
- break;
- }
-
- lll_unlock (__pthread_keys_lock);
-
- return result;
+ for (size_t cnt = 0; cnt < PTHREAD_KEYS_MAX; ++cnt)
+ {
+ uintptr_t seq = __pthread_keys[cnt].seq;
+
+ if (KEY_UNUSED (seq) && KEY_USABLE (seq)
+ /* We found an unused slot. Try to allocate it. */
+ && ! atomic_compare_and_exchange_bool_acq (&__pthread_keys[cnt].seq,
+ seq + 1, seq))
+ {
+ /* Remember the destructor. */
+ __pthread_keys[cnt].destr = destr;
+
+ /* Return the key to the caller. */
+ *key = cnt;
+
+ /* The call succeeded. */
+ return 0;
+ }
+ }
+
+ return EAGAIN;
}
strong_alias (__pthread_key_create, pthread_key_create)
strong_alias (__pthread_key_create, __pthread_key_create_internal)