[tip: locking/core] locking/rtmutex: Switch to from cmpxchg_*() to try_cmpxchg_*()

[tip-bot2 for Thomas Gleixner]

The following commit has been merged into the locking/core branch of tip:

Commit-ID:     709e0b62869f625afd18edd79f190c38cb39dfb2
Gitweb:        https://git.kernel.org/tip/709e0b62869f625afd18edd79f190c38cb39dfb2
Author:        Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate:    Sun, 15 Aug 2021 23:27:55 +02:00
Committer:     Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Tue, 17 Aug 2021 17:01:47 +02:00

locking/rtmutex: Switch to from cmpxchg_*() to try_cmpxchg_*()

Allows the compiler to generate better code depending on the architecture.

Suggested-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210815211302.668958502@xxxxxxxxxxxxx
---
 kernel/locking/rtmutex.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 5187add..98f06c5 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -145,14 +145,14 @@ static __always_inline bool rt_mutex_cmpxchg_acquire(struct rt_mutex *lock,
 						     struct task_struct *old,
 						     struct task_struct *new)
 {
-	return cmpxchg_acquire(&lock->owner, old, new) == old;
+	return try_cmpxchg_acquire(&lock->owner, &old, new);
 }
 
 static __always_inline bool rt_mutex_cmpxchg_release(struct rt_mutex *lock,
 						     struct task_struct *old,
 						     struct task_struct *new)
 {
-	return cmpxchg_release(&lock->owner, old, new) == old;
+	return try_cmpxchg_release(&lock->owner, &old, new);
 }
 
 /*