Fix __wait_on_atomic_t() to call the action func if the counter != 0
authorDavid Howells <dhowells@redhat.com>
Tue, 23 Jul 2013 15:49:24 +0000 (16:49 +0100)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 23 Jul 2013 22:46:48 +0000 (15:46 -0700)
Fix __wait_on_atomic_t() so that it calls the action func if the counter != 0
rather than if the counter is 0 so as to be analogous to __wait_on_bit().

Thanks to Yacine who found this by visual inspection.

This will affect FS-Cache in that it will could fail to sleep correctly when
trying to clean up after a netfs cookie is withdrawn.

Reported-by: Yacine Belkadi <yacine.belkadi.1@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
cc: Milosz Tanski <milosz@adfin.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/wait.c

index ce0daa320a261f1aebfc5e16d7d7b3e7caf71c37..dec68bd4e9d8e996404faa065b67354f1defa8eb 100644 (file)
@@ -333,7 +333,8 @@ int __wait_on_atomic_t(wait_queue_head_t *wq, struct wait_bit_queue *q,
                prepare_to_wait(wq, &q->wait, mode);
                val = q->key.flags;
                if (atomic_read(val) == 0)
-                       ret = (*action)(val);
+                       break;
+               ret = (*action)(val);
        } while (!ret && atomic_read(val) != 0);
        finish_wait(wq, &q->wait);
        return ret;