| Message ID | 1407358496-23094-1-git-send-email-kamal@canonical.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Aug 6, 2014 at 4:54 PM, Kamal Mostafa <kamal@canonical.com> wrote: > This is a note to let you know that I have just added a patch titled > > locking/mutex: Disable optimistic spinning on some architectures > > to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree > which can be found at: > > http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue > > This patch is scheduled to be released in version 3.13.11.6. > This patch is specifically for parisc, sparc32, tile32, metag-lock1, arc-!llsc and hexagon none of which Ubuntu supports. Why are you backporting this patch? -- Andev
On Wed, 2014-08-06 at 17:25 -0400, Andev wrote: > On Wed, Aug 6, 2014 at 4:54 PM, Kamal Mostafa <kamal@canonical.com> wrote: > > This is a note to let you know that I have just added a patch titled > > > > locking/mutex: Disable optimistic spinning on some architectures > > > > to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree > > which can be found at: > > > > http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue > > > > This patch is scheduled to be released in version 3.13.11.6. > > > > This patch is specifically for parisc, sparc32, tile32, metag-lock1, > arc-!llsc and hexagon none of which Ubuntu supports. > > Why are you backporting this patch? Well 3.13.y.z isn't an Ubuntu kernel, its upstream, and those archs *are* supported.
On Wed, 6 Aug 2014, Andev wrote: > On Wed, Aug 6, 2014 at 4:54 PM, Kamal Mostafa <kamal@canonical.com> wrote: > > This is a note to let you know that I have just added a patch titled > > > > locking/mutex: Disable optimistic spinning on some architectures > > > > to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree > > which can be found at: > > > > http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue > > > > This patch is scheduled to be released in version 3.13.11.6. > > > > This patch is specifically for parisc, sparc32, tile32, metag-lock1, > arc-!llsc and hexagon none of which Ubuntu supports. > > Why are you backporting this patch? > > -- > Andev I guess - it's less time consuming to backport all patches for stable than to ponder on each patch if it applies to Ubuntu or not... Mikulas
> On Wed, 2014-08-06 at 17:25 -0400, Andev wrote: > > On Wed, Aug 6, 2014 at 4:54 PM, Kamal Mostafa <kamal@canonical.com> wrote: > > > This is a note to let you know that I have just added a patch titled > > > > > > locking/mutex: Disable optimistic spinning on some architectures > > > > > > to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree > > > which can be found at: > > > > > > http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue > > > > > > This patch is scheduled to be released in version 3.13.11.6. > > > > > > > This patch is specifically for parisc, sparc32, tile32, metag-lock1, > > arc-!llsc and hexagon none of which Ubuntu supports. > > > > Why are you backporting this patch? On Wed, 2014-08-06 at 14:30 -0700, Davidlohr Bueso wrote: > Well 3.13.y.z isn't an Ubuntu kernel, its upstream, and those archs > *are* supported. Davidlohr's answer is correct: This is not an "Ubuntu kernel". 3.13.y.z is an "extended stable" kernel which follows the same rules as the kernel.org official stable kernels. It contains no Ubuntu-specific patches, and supports the same arch's as mainline. More details about this and the other Canonical-funded-and-hosted "extended stable" kernel versions is available here: > For more information about the 3.13.y.z tree, see > https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable -Kamal
On Wed, Aug 6, 2014 at 9:55 PM, Kamal Mostafa <kamal@canonical.com> wrote: > > On Wed, 2014-08-06 at 14:30 -0700, Davidlohr Bueso wrote: >> Well 3.13.y.z isn't an Ubuntu kernel, its upstream, and those archs >> *are* supported. > > Davidlohr's answer is correct: This is not an "Ubuntu kernel". > > 3.13.y.z is an "extended stable" kernel which follows the same rules as > the kernel.org official stable kernels. It contains no Ubuntu-specific > patches, and supports the same arch's as mainline. > > More details about this and the other Canonical-funded-and-hosted > "extended stable" kernel versions is available here: > >> For more information about the 3.13.y.z tree, see >> https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable OK, thank you for clarification. I was unsure as this is not hosted on kernel.org, I thought it was a Ubuntu specific kernel. So we have the following stable kernels as of now: 3.10, 3.12, 3.13, 3.14, 3.15(for a few days), 3.16! Interesting.
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 31e1f44..b3d400d 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_CMPXCHG_LOCKREF select ARCH_WANT_IPC_PARSE_VERSION select BUILDTIME_EXTABLE_SORT if MMU diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 6d4dd22..bf0ed5d 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -2,6 +2,7 @@ config ARM64 def_bool y select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 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 b44b52c..ab43fa3 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -139,6 +139,7 @@ config PPC select OLD_SIGACTION if PPC32 select HAVE_DEBUG_STACKOVERFLOW select HAVE_IRQ_EXIT_ON_IRQ_STACK + select ARCH_SUPPORTS_ATOMIC_RMW config GENERIC_CSUM def_bool CPU_LITTLE_ENDIAN diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 6c95f4d..94cd9c1 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -76,6 +76,7 @@ config SPARC64 select ARCH_HAVE_NMI_SAFE_CMPXCHG select HAVE_C_RECORDMCOUNT select NO_BOOTMEM + select ARCH_SUPPORTS_ATOMIC_RMW config ARCH_DEFCONFIG string diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 9e31880..9562fc3 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -125,6 +125,7 @@ config X86 select RTC_LIB select HAVE_DEBUG_STACKOVERFLOW select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 + select ARCH_SUPPORTS_ATOMIC_RMW config INSTRUCTION_DECODER def_bool y diff --git a/kernel/Kconfig.locks b/kernel/Kconfig.locks index d2b32ac..ecee67a 100644 --- a/kernel/Kconfig.locks +++ b/kernel/Kconfig.locks @@ -220,6 +220,9 @@ 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
This is a note to let you know that I have just added a patch titled locking/mutex: Disable optimistic spinning on some architectures to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11.6. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 01698736c59ec0ef7db9aa25785868ebd5637e12 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra <peterz@infradead.org> Date: Fri, 6 Jun 2014 19:53:16 +0200 Subject: 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> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- 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(-) -- 1.9.1