diff options
author | Peter Zijlstra <peterz@infradead.org> | 2014-06-06 19:53:16 +0200 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2014-08-06 18:07:38 +0100 |
commit | e87c95f8ac1ec35ebf4d144d4b46e2ecf153ffd4 (patch) | |
tree | f9f7aa9fb4a60d7974c29a0805c7b597fb698e7d | |
parent | 8f88141b2724459ab757b44a5251cd915169f5de (diff) |
locking/mutex: Disable optimistic spinning on some architectures
commit 4badad352a6bb202ec68afa7a574c0bb961e5ebc upstream.
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@infradead.org>
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Jason Low <jason.low2@hp.com>
Cc: Waiman Long <waiman.long@hp.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: John David Anglin <dave.anglin@bell.net>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Link: http://lkml.kernel.org/r/20140606175316.GV13930@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.2:
- Adjust context
- Drop arm64 change]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-rw-r--r-- | arch/arm/Kconfig | 1 | ||||
-rw-r--r-- | arch/powerpc/Kconfig | 1 | ||||
-rw-r--r-- | arch/sparc/Kconfig | 1 | ||||
-rw-r--r-- | arch/x86/Kconfig | 1 | ||||
-rw-r--r-- | kernel/Kconfig.locks | 6 |
5 files changed, 9 insertions, 1 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 790ea68ecf8..082bd366928 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1,6 +1,7 @@ config ARM bool default y + select ARCH_SUPPORTS_ATOMIC_RMW select HAVE_DMA_API_DEBUG select HAVE_IDE if PCI || ISA || PCMCIA select HAVE_MEMBLOCK diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 16ef838b3cb..bec952d8903 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -137,6 +137,7 @@ config PPC select HAVE_BPF_JIT if (PPC64 && NET) select HAVE_ARCH_JUMP_LABEL select ARCH_HAVE_NMI_SAFE_CMPXCHG + select ARCH_SUPPORTS_ATOMIC_RMW config EARLY_PRINTK bool diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 88d442d49ac..f2f3574dcdf 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -57,6 +57,7 @@ config SPARC64 select IRQ_PREFLOW_FASTEOI select ARCH_HAVE_NMI_SAFE_CMPXCHG select HAVE_C_RECORDMCOUNT + select ARCH_SUPPORTS_ATOMIC_RMW config ARCH_DEFCONFIG string diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index fb2e69db9c7..901447e3a42 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -75,6 +75,7 @@ config X86 select HAVE_BPF_JIT if (X86_64 && NET) select CLKEVT_I8253 select ARCH_HAVE_NMI_SAFE_CMPXCHG + select ARCH_SUPPORTS_ATOMIC_RMW config INSTRUCTION_DECODER def_bool (KPROBES || PERF_EVENTS) diff --git a/kernel/Kconfig.locks b/kernel/Kconfig.locks index 5068e2a4e75..61ebb49bdee 100644 --- a/kernel/Kconfig.locks +++ b/kernel/Kconfig.locks @@ -198,5 +198,9 @@ config INLINE_WRITE_UNLOCK_IRQ config INLINE_WRITE_UNLOCK_IRQRESTORE def_bool !DEBUG_SPINLOCK && ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE +config ARCH_SUPPORTS_ATOMIC_RMW + bool + config MUTEX_SPIN_ON_OWNER - def_bool SMP && !DEBUG_MUTEXES + def_bool y + depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW |