[tip: locking/core] locking/x86: Define arch_try_cmpxchg_local()

From: tip-bot2 for Uros Bizjak
Date: Sat Apr 29 2023 - 03:04:50 EST


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

Commit-ID: 1ab70804ef3f829c5a738cba8627f0a0c2486d2b
Gitweb: https://git.kernel.org/tip/1ab70804ef3f829c5a738cba8627f0a0c2486d2b
Author: Uros Bizjak <ubizjak@xxxxxxxxx>
AuthorDate: Wed, 05 Apr 2023 16:17:09 +02:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Sat, 29 Apr 2023 08:52:44 +02:00

locking/x86: Define arch_try_cmpxchg_local()

Define target specific arch_try_cmpxchg_local(). This
definition overrides the generic arch_try_cmpxchg_local()
fallback definition and enables target-specific
implementation of try_cmpxchg_local().

Signed-off-by: Uros Bizjak <ubizjak@xxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230405141710.3551-5-ubizjak@xxxxxxxxx
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
---
arch/x86/include/asm/cmpxchg.h | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/arch/x86/include/asm/cmpxchg.h b/arch/x86/include/asm/cmpxchg.h
index 94fbe6a..540573f 100644
--- a/arch/x86/include/asm/cmpxchg.h
+++ b/arch/x86/include/asm/cmpxchg.h
@@ -221,9 +221,15 @@ extern void __add_wrong_size(void)
#define __try_cmpxchg(ptr, pold, new, size) \
__raw_try_cmpxchg((ptr), (pold), (new), (size), LOCK_PREFIX)

+#define __try_cmpxchg_local(ptr, pold, new, size) \
+ __raw_try_cmpxchg((ptr), (pold), (new), (size), "")
+
#define arch_try_cmpxchg(ptr, pold, new) \
__try_cmpxchg((ptr), (pold), (new), sizeof(*(ptr)))

+#define arch_try_cmpxchg_local(ptr, pold, new) \
+ __try_cmpxchg_local((ptr), (pold), (new), sizeof(*(ptr)))
+
/*
* xadd() adds "inc" to "*ptr" and atomically returns the previous
* value of "*ptr".