3.2.63-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Christian Borntraeger <borntrae...@de.ibm.com>
commit 36e7fdaa1a04fcf65b864232e1af56a51c7814d6 upstream.
commit 4badad352a6bb202ec68afa7a574c0bb961e5ebc (locking/mutex: Disable
optimistic spinning on some architectures) fenced spinning for
architectures without proper cmpxchg.
There is no need to disable mutex spinning on s390, though:
The instructions CS,CSG and friends provide the proper guarantees.
(We dont implement cmpxchg with locks).
Signed-off-by: Christian Borntraeger <borntrae...@de.ibm.com>
Cc: Ingo Molnar <mi...@kernel.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Signed-off-by: Heiko Carstens <heiko.carst...@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidef...@de.ibm.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
arch/s390/Kconfig | 1 +
1 file changed, 1 insertion(+)
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -119,6 +119,7 @@ config S390
select ARCH_INLINE_WRITE_UNLOCK_BH
select ARCH_INLINE_WRITE_UNLOCK_IRQ
select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
+ select ARCH_SUPPORTS_ATOMIC_RMW
config SCHED_OMIT_FRAME_POINTER
def_bool y
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
