Commit 8fe46535 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Peter Zijlstra
Browse files

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: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210928150006.597310-2-bigeasy@linutronix.de
parent ef1f4804

kernel/locking/rtmutex.c

+1 −1
Original line number Diff line number Diff line
@@ -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);