Commit-ID: 4badad352a6bb202ec68afa7a574c0bb961e5ebc Gitweb: http://git.kernel.org/tip/4badad352a6bb202ec68afa7a574c0bb961e5ebc Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx> AuthorDate: Fri, 6 Jun 2014 19:53:16 +0200 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Wed, 16 Jul 2014 14:57:07 +0200 locking/mutex: Disable optimistic spinning on some architectures The optimistic spin code assumes regular stores and cmpxchg() play nice; this is found to not be true for at least: parisc, sparc32, tile32, metag-lock1, arc-!llsc and hexagon. There is further wreckage, but this in particular seemed easy to trigger, so blacklist this. Opt in for known good archs. Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Reported-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> Cc: David Miller <davem@xxxxxxxxxxxxx> Cc: Chris Metcalf <cmetcalf@xxxxxxxxxx> Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx> Cc: Jason Low <jason.low2@xxxxxx> Cc: Waiman Long <waiman.long@xxxxxx> Cc: "James E.J. Bottomley" <jejb@xxxxxxxxxxxxxxxx> Cc: Paul McKenney <paulmck@xxxxxxxxxxxxxxxxxx> Cc: John David Anglin <dave.anglin@xxxxxxxx> Cc: James Hogan <james.hogan@xxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Davidlohr Bueso <davidlohr@xxxxxx> Cc: stable@xxxxxxxxxxxxxxx Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: linuxppc-dev@xxxxxxxxxxxxxxxx Cc: sparclinux@xxxxxxxxxxxxxxx Link: http://lkml.kernel.org/r/20140606175316.GV13930@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/arm/Kconfig | 1 + arch/arm64/Kconfig | 1 + arch/powerpc/Kconfig | 1 + arch/sparc/Kconfig | 1 + arch/x86/Kconfig | 1 + kernel/Kconfig.locks | 5 ++++- 6 files changed, 9 insertions(+), 1 deletion(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 245058b..88acf8b 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -6,6 +6,7 @@ config ARM select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_HAVE_CUSTOM_GPIO_H select ARCH_MIGHT_HAVE_PC_PARPORT + select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_USE_BUILTIN_BSWAP select ARCH_USE_CMPXCHG_LOCKREF select ARCH_WANT_IPC_PARSE_VERSION diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index a474de34..839f48c 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -4,6 +4,7 @@ config ARM64 select ARCH_HAS_OPP select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_USE_CMPXCHG_LOCKREF + select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_WANT_OPTIONAL_GPIOLIB select ARCH_WANT_COMPAT_IPC_PARSE_VERSION select ARCH_WANT_FRAME_POINTERS diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index fefe7c8..80b94b0 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -145,6 +145,7 @@ config PPC select HAVE_IRQ_EXIT_ON_IRQ_STACK select ARCH_USE_CMPXCHG_LOCKREF if PPC64 select HAVE_ARCH_AUDITSYSCALL + select ARCH_SUPPORTS_ATOMIC_RMW config GENERIC_CSUM def_bool CPU_LITTLE_ENDIAN diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 29f2e98..407c87d 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -78,6 +78,7 @@ config SPARC64 select HAVE_C_RECORDMCOUNT select NO_BOOTMEM select HAVE_ARCH_AUDITSYSCALL + select ARCH_SUPPORTS_ATOMIC_RMW config ARCH_DEFCONFIG string diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index a8f749e..d24887b 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -131,6 +131,7 @@ config X86 select HAVE_CC_STACKPROTECTOR select GENERIC_CPU_AUTOPROBE select HAVE_ARCH_AUDITSYSCALL + select ARCH_SUPPORTS_ATOMIC_RMW config INSTRUCTION_DECODER def_bool y diff --git a/kernel/Kconfig.locks b/kernel/Kconfig.locks index 35536d9..8190794 100644 --- a/kernel/Kconfig.locks +++ b/kernel/Kconfig.locks @@ -220,9 +220,12 @@ config INLINE_WRITE_UNLOCK_IRQRESTORE endif +config ARCH_SUPPORTS_ATOMIC_RMW + bool + config MUTEX_SPIN_ON_OWNER def_bool y - depends on SMP && !DEBUG_MUTEXES + depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW config ARCH_USE_QUEUE_RWLOCK bool -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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