The following commit has been merged into the locking/core branch of tip:
Commit-ID: 8fe46535e10dbfebad68ad9f2f8260e49f5852c9
Gitweb: https://git.kernel.org/tip/8fe46535e10dbfebad68ad9f2f8260e49f5852c9
Author: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
AuthorDate: Tue, 28 Sep 2021 17:00:05 +02:00
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Fri, 01 Oct 2021 13:57:52 +02:00
rtmutex: Check explicit for TASK_RTLOCK_WAIT.
rt_mutex_wake_q_add() needs to need to distiguish between sleeping
locks (TASK_RTLOCK_WAIT) and normal locks which use TASK_NORMAL to use
the proper wake mechanism.
Instead of checking for != TASK_NORMAL make it more robust and check
explicit for TASK_RTLOCK_WAIT which is the reason why a different wake
mechanism is used.
No functional change.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20210928150006.597310-2-bigeasy@xxxxxxxxxxxxx
---
kernel/locking/rtmutex.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 6bb116c..cafc259 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -449,7 +449,7 @@ static __always_inline void rt_mutex_adjust_prio(struct task_struct *p)
static __always_inline void rt_mutex_wake_q_add(struct rt_wake_q_head *wqh,
struct rt_mutex_waiter *w)
{
- if (IS_ENABLED(CONFIG_PREEMPT_RT) && w->wake_state != TASK_NORMAL) {
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && w->wake_state == TASK_RTLOCK_WAIT) {
if (IS_ENABLED(CONFIG_PROVE_LOCKING))
WARN_ON_ONCE(wqh->rtlock_task);
get_task_struct(w->task);
|