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Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/sem_post.c')
-rw-r--r--nptl/sysdeps/unix/sysv/linux/sem_post.c33
1 files changed, 28 insertions, 5 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/sem_post.c b/nptl/sysdeps/unix/sysv/linux/sem_post.c
index 671b43f7f7..7f90325585 100644
--- a/nptl/sysdeps/unix/sysv/linux/sem_post.c
+++ b/nptl/sysdeps/unix/sysv/linux/sem_post.c
@@ -1,5 +1,5 @@
/* sem_post -- post to a POSIX semaphore. Generic futex-using version.
- Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2007 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jakub@redhat.com>, 2003.
@@ -29,10 +29,36 @@
int
__new_sem_post (sem_t *sem)
{
+ struct new_sem *isem = (struct new_sem *) sem;
+
+ int nr = atomic_increment_val (&isem->value);
+ atomic_full_barrier ();
+ if (isem->nwaiters > 0)
+ {
+ int err = lll_futex_wake (&isem->value, 1,
+ // XYZ check mutex flag
+ LLL_SHARED);
+ if (__builtin_expect (err, 0) < 0)
+ {
+ __set_errno (-err);
+ return -1;
+ }
+ }
+ return 0;
+}
+versioned_symbol (libpthread, __new_sem_post, sem_post, GLIBC_2_1);
+
+
+#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
+int
+attribute_compat_text_section
+__old_sem_post (sem_t *sem)
+{
int *futex = (int *) sem;
int nr = atomic_increment_val (futex);
- int err = lll_futex_wake (futex, nr);
+ /* We always have to assume it is a shared semaphore. */
+ int err = lll_futex_wake (futex, 1, LLL_SHARED);
if (__builtin_expect (err, 0) < 0)
{
__set_errno (-err);
@@ -40,8 +66,5 @@ __new_sem_post (sem_t *sem)
}
return 0;
}
-versioned_symbol (libpthread, __new_sem_post, sem_post, GLIBC_2_1);
-#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
-strong_alias (__new_sem_post, __old_sem_post)
compat_symbol (libpthread, __old_sem_post, sem_post, GLIBC_2_0);
#endif