diff options
| author | Paul Gortmaker <paul.gortmaker@windriver.com> | 2013-08-27 14:20:26 -0400 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2013-11-13 11:21:27 -0500 |
| commit | c53e70dbe9288ef8952cc1083fa7cdf88bf442c3 (patch) | |
| tree | 69ec9244e6756f3f6c0bccc9d6d99ec1dc2498ad /include/linux | |
| parent | 1dd317c5ebffcad01222f96551cb5e4b8b9fd605 (diff) | |
simple-wait: rename and export the equivalent of waitqueue_active()
The function "swait_head_has_waiters()" was internalized into
wait-simple.c but it parallels the waitqueue_active of normal
waitqueue support. Given that there are over 150 waitqueue_active
users in drivers/ fs/ kernel/ and the like, lets make it globally
visible, and rename it to parallel the waitqueue_active accordingly.
We'll need to do this if we expect to expand its usage beyond RT.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/wait-simple.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/wait-simple.h b/include/linux/wait-simple.h index 4efba4d28c48..f86bca2c41d5 100644 --- a/include/linux/wait-simple.h +++ b/include/linux/wait-simple.h @@ -47,6 +47,14 @@ extern void swait_prepare(struct swait_head *head, struct swaiter *w, int state) extern void swait_finish_locked(struct swait_head *head, struct swaiter *w); extern void swait_finish(struct swait_head *head, struct swaiter *w); +/* Check whether a head has waiters enqueued */ +static inline bool swaitqueue_active(struct swait_head *h) +{ + /* Make sure the condition is visible before checking list_empty() */ + smp_mb(); + return !list_empty(&h->list); +} + /* * Wakeup functions */ |