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-rw-r--r--nptl/sem_wait.c101
1 files changed, 35 insertions, 66 deletions
diff --git a/nptl/sem_wait.c b/nptl/sem_wait.c
index df11933b69..c1fd10c9d0 100644
--- a/nptl/sem_wait.c
+++ b/nptl/sem_wait.c
@@ -17,80 +17,18 @@
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
-#include <errno.h>
-#include <sysdep.h>
-#include <lowlevellock.h>
-#include <internaltypes.h>
-#include <semaphore.h>
-
-#include <pthreadP.h>
-#include <shlib-compat.h>
-#include <atomic.h>
-
-
-void
-attribute_hidden
-__sem_wait_cleanup (void *arg)
-{
- struct new_sem *isem = (struct new_sem *) arg;
-
- atomic_decrement (&isem->nwaiters);
-}
-
-/* This is in a seperate function in order to make sure gcc
- puts the call site into an exception region, and thus the
- cleanups get properly run. */
-static int
-__attribute__ ((noinline))
-do_futex_wait (struct new_sem *isem)
-{
- int err, oldtype = __pthread_enable_asynccancel ();
-
- err = lll_futex_wait (&isem->value, 0, isem->private ^ FUTEX_PRIVATE_FLAG);
-
- __pthread_disable_asynccancel (oldtype);
- return err;
-}
+#include "sem_waitcommon.c"
int
__new_sem_wait (sem_t *sem)
{
- struct new_sem *isem = (struct new_sem *) sem;
- int err;
-
- if (atomic_decrement_if_positive (&isem->value) > 0)
+ if (__new_sem_wait_fast ((struct new_sem *) sem, 0) == 0)
return 0;
-
- atomic_increment (&isem->nwaiters);
-
- pthread_cleanup_push (__sem_wait_cleanup, isem);
-
- while (1)
- {
- err = do_futex_wait(isem);
- if (err != 0 && err != -EWOULDBLOCK)
- {
- __set_errno (-err);
- err = -1;
- break;
- }
-
- if (atomic_decrement_if_positive (&isem->value) > 0)
- {
- err = 0;
- break;
- }
- }
-
- pthread_cleanup_pop (0);
-
- atomic_decrement (&isem->nwaiters);
-
- return err;
+ else
+ return __new_sem_wait_slow((struct new_sem *) sem, NULL);
}
versioned_symbol (libpthread, __new_sem_wait, sem_wait, GLIBC_2_1);
-
#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
int
attribute_compat_text_section
@@ -121,3 +59,34 @@ __old_sem_wait (sem_t *sem)
compat_symbol (libpthread, __old_sem_wait, sem_wait, GLIBC_2_0);
#endif
+
+int
+__new_sem_trywait (sem_t *sem)
+{
+ /* We must not fail spuriously, so require a definitive result even if this
+ may lead to a long execution time. */
+ if (__new_sem_wait_fast ((struct new_sem *) sem, 1) == 0)
+ return 0;
+ __set_errno (EAGAIN);
+ return -1;
+}
+versioned_symbol (libpthread, __new_sem_trywait, sem_trywait, GLIBC_2_1);
+#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
+int
+__old_sem_trywait (sem_t *sem)
+{
+ int *futex = (int *) sem;
+ int val;
+
+ if (*futex > 0)
+ {
+ val = atomic_decrement_if_positive (futex);
+ if (val > 0)
+ return 0;
+ }
+
+ __set_errno (EAGAIN);
+ return -1;
+}
+compat_symbol (libpthread, __old_sem_trywait, sem_trywait, GLIBC_2_0);
+#endif