lkml.org 
[lkml]   [2009]   [Apr]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip:core/locking] mutex: add atomic_dec_and_mutex_lock(), fix
Commit-ID:  a511e3f968c462a55ef58697257f5347c73d306e
Gitweb: http://git.kernel.org/tip/a511e3f968c462a55ef58697257f5347c73d306e
Author: Andrew Morton <akpm@linux-foundation.org>
AuthorDate: Wed, 29 Apr 2009 15:59:58 -0700
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Thu, 30 Apr 2009 09:01:34 +0200

mutex: add atomic_dec_and_mutex_lock(), fix

include/linux/mutex.h:136: warning: 'mutex_lock' declared inline after being called
include/linux/mutex.h:136: warning: previous declaration of 'mutex_lock' was here

uninline it.

[ Impact: clean up and uninline, address compiler warning ]

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Eric Paris <eparis@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <200904292318.n3TNIsi6028340@imap1.linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>


---
include/linux/mutex.h | 24 +-----------------------
kernel/mutex.c | 25 ++++++++++++++++++++++++-
2 files changed, 25 insertions(+), 24 deletions(-)

diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index 93054fc..878cab4 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -150,28 +150,6 @@ extern int __must_check mutex_lock_killable(struct mutex *lock);
*/
extern int mutex_trylock(struct mutex *lock);
extern void mutex_unlock(struct mutex *lock);
-
-/**
- * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0
- * @cnt: the atomic which we are to dec
- * @lock: the mutex to return holding if we dec to 0
- *
- * return true and hold lock if we dec to 0, return false otherwise
- */
-static inline int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock)
-{
- /* dec if we can't possibly hit 0 */
- if (atomic_add_unless(cnt, -1, 1))
- return 0;
- /* we might hit 0, so take the lock */
- mutex_lock(lock);
- if (!atomic_dec_and_test(cnt)) {
- /* when we actually did the dec, we didn't hit 0 */
- mutex_unlock(lock);
- return 0;
- }
- /* we hit 0, and we hold the lock */
- return 1;
-}
+extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);

#endif
diff --git a/kernel/mutex.c b/kernel/mutex.c
index 507cf2b..e2d25e9 100644
--- a/kernel/mutex.c
+++ b/kernel/mutex.c
@@ -471,5 +471,28 @@ int __sched mutex_trylock(struct mutex *lock)

return ret;
}
-
EXPORT_SYMBOL(mutex_trylock);
+
+/**
+ * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0
+ * @cnt: the atomic which we are to dec
+ * @lock: the mutex to return holding if we dec to 0
+ *
+ * return true and hold lock if we dec to 0, return false otherwise
+ */
+int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock)
+{
+ /* dec if we can't possibly hit 0 */
+ if (atomic_add_unless(cnt, -1, 1))
+ return 0;
+ /* we might hit 0, so take the lock */
+ mutex_lock(lock);
+ if (!atomic_dec_and_test(cnt)) {
+ /* when we actually did the dec, we didn't hit 0 */
+ mutex_unlock(lock);
+ return 0;
+ }
+ /* we hit 0, and we hold the lock */
+ return 1;
+}
+EXPORT_SYMBOL(atomic_dec_and_mutex_lock);

\
 
 \ /
  Last update: 2009-04-30 09:07    [W:0.026 / U:0.012 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site