We don't need to adjust prio before new pi_waiter adding. The prio
only need update after pi_waiter change or task priority change.
Steven Rostedt pointed:
"Interesting, I did some git mining and this was added with the original
entry of the rtmutex.c (23f78d4a0). Looking at even that version, I
don't see the purpose of adjusting the task prio here. It is done
before anything changes in the task."
Signed-off-by: Alex Shi <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Sebastian Siewior <[email protected]>
Cc: Mathieu Poirier <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Thomas Gleixner <[email protected]>
To: [email protected]
To: Ingo Molnar <[email protected]>
To: Peter Zijlstra <[email protected]>
Reviewed-by: Steven Rostedt (VMware) <[email protected]>
---
kernel/locking/rtmutex.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 28cd09e..d1fe41f 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -963,7 +963,6 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
return -EDEADLK;
raw_spin_lock(&task->pi_lock);
- rt_mutex_adjust_prio(task);
waiter->task = task;
waiter->lock = lock;
waiter->prio = task->prio;
--
2.7.4
Commit-ID: 69f0d429c413fe96db2c187475cebcc6e3a8c7f5
Gitweb: http://git.kernel.org/tip/69f0d429c413fe96db2c187475cebcc6e3a8c7f5
Author: Alex Shi <[email protected]>
AuthorDate: Thu, 13 Jul 2017 14:18:24 +0800
Committer: Ingo Molnar <[email protected]>
CommitDate: Thu, 13 Jul 2017 11:44:06 +0200
locking/rtmutex: Remove unnecessary priority adjustment
We don't need to adjust priority before adding a new pi_waiter, the
priority only needs to be updated after pi_waiter change or task
priority change.
Steven Rostedt pointed out:
"Interesting, I did some git mining and this was added with the original
entry of the rtmutex.c (23f78d4a03c5). Looking at even that version, I
don't see the purpose of adjusting the task prio here. It is done
before anything changes in the task."
Signed-off-by: Alex Shi <[email protected]>
Reviewed-by: Steven Rostedt (VMware) <[email protected]>
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mathieu Poirier <[email protected]>
Cc: Sebastian Siewior <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
[ Enhance the changelog. ]
Signed-off-by: Ingo Molnar <[email protected]>
---
kernel/locking/rtmutex.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 7806989..649dc9d 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -963,7 +963,6 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
return -EDEADLK;
raw_spin_lock(&task->pi_lock);
- rt_mutex_adjust_prio(task);
waiter->task = task;
waiter->lock = lock;
waiter->prio = task->prio;