From: Thomas Gleixner <tglx@linutronix.de>
Date: Sun, 15 Aug 2021 21:27:55 +0000 (+0200)
Subject: locking/rtmutex: Switch to from cmpxchg_*() to try_cmpxchg_*()
X-Git-Tag: v5.15-rc1~119^2~62
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=709e0b62869f625afd18edd79f190c38cb39dfb2;p=thirdparty%2Fkernel%2Flinux.git

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@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211302.668958502@linutronix.de
---

diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 5187added8bce..98f06c509f023 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);
 }
 
 /*