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* Merge branch 'timers-2038-for-linus' of ↵Linus Torvalds2018-06-042-41/+34
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull time/Y2038 updates from Thomas Gleixner: - Consolidate SySV IPC UAPI headers - Convert SySV IPC to the new COMPAT_32BIT_TIME mechanism - Cleanup the core interfaces and standardize on the ktime_get_* naming convention. - Convert the X86 platform ops to timespec64 - Remove the ugly temporary timespec64 hack * 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) x86: Convert x86_platform_ops to timespec64 timekeeping: Add more coarse clocktai/boottime interfaces timekeeping: Add ktime_get_coarse_with_offset timekeeping: Standardize on ktime_get_*() naming timekeeping: Clean up ktime_get_real_ts64 timekeeping: Remove timespec64 hack y2038: ipc: Redirect ipc(SEMTIMEDOP, ...) to compat_ksys_semtimedop y2038: ipc: Enable COMPAT_32BIT_TIME y2038: ipc: Use __kernel_timespec y2038: ipc: Report long times to user space y2038: ipc: Use ktime_get_real_seconds consistently y2038: xtensa: Extend sysvipc data structures y2038: powerpc: Extend sysvipc data structures y2038: sparc: Extend sysvipc data structures y2038: parisc: Extend sysvipc data structures y2038: mips: Extend sysvipc data structures y2038: arm64: Extend sysvipc compat data structures y2038: s390: Remove unneeded ipc uapi header files y2038: ia64: Remove unneeded ipc uapi header files y2038: alpha: Remove unneeded ipc uapi header files ...
| * timekeeping: Add ktime_get_coarse_with_offsetArnd Bergmann2018-05-191-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I have run into a couple of drivers using current_kernel_time() suffering from the y2038 problem, and they could be converted to using ktime_t, but don't have interfaces that skip the nanosecond calculation at the moment. This introduces ktime_get_coarse_with_offset() as a simpler variant of ktime_get_with_offset(), and adds wrappers for the three time domains we support with the existing function. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: y2038@lists.linaro.org Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180427134016.2525989-5-arnd@arndb.de
| * timekeeping: Standardize on ktime_get_*() namingArnd Bergmann2018-05-191-14/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current_kernel_time64, get_monotonic_coarse64, getrawmonotonic64, get_monotonic_boottime64 and timekeeping_clocktai64 interfaces have rather inconsistent naming, and they differ in the calling conventions by passing the output either by reference or as a return value. Rename them to ktime_get_coarse_real_ts64, ktime_get_coarse_ts64, ktime_get_raw_ts64, ktime_get_boottime_ts64 and ktime_get_clocktai_ts64 respectively, and provide the interfaces with macros or inline functions as needed. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: y2038@lists.linaro.org Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180427134016.2525989-4-arnd@arndb.de
| * timekeeping: Clean up ktime_get_real_ts64Arnd Bergmann2018-05-191-25/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In a move to make ktime_get_*() the preferred driver interface into the timekeeping code, sanitizes ktime_get_real_ts64() to be a proper exported symbol rather than an alias for getnstimeofday64(). The internal __getnstimeofday64() is no longer used, so remove that and merge it into ktime_get_real_ts64(). Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: y2038@lists.linaro.org Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180427134016.2525989-3-arnd@arndb.de
| * timekeeping: Remove timespec64 hackArnd Bergmann2018-05-191-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At this point, we have converted most of the kernel to use timespec64 consistently in place of timespec, so it seems it's time to make timespec64 the native structure and define timespec in terms of that one on 64-bit architectures. Starting with gcc-5, the compiler can completely optimize away the timespec_to_timespec64 and timespec64_to_timespec functions on 64-bit architectures. With older compilers, we introduce a couple of extra copies of local variables, but those are easily avoided by using the timespec64 based interfaces consistently, as we do in most of the important code paths already. The main upside of removing the hack is that printing the tv_sec field of a timespec64 structure can now use the %lld format string on all architectures without a cast to time64_t. Without this patch, the field is a 'long' type and would have to be printed using %ld on 64-bit architectures. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: y2038@lists.linaro.org Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180427134016.2525989-2-arnd@arndb.de
| * Merge branch 'linus' into timers/2038Thomas Gleixner2018-05-1942-433/+506
| |\ | | | | | | | | | Merge upstream to pick up changes on which pending patches depend on.
* | \ Merge branch 'timers-core-for-linus' of ↵Linus Torvalds2018-06-049-96/+114
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timers and timekeeping updates from Thomas Gleixner: - Core infrastucture work for Y2038 to address the COMPAT interfaces: + Add a new Y2038 safe __kernel_timespec and use it in the core code + Introduce config switches which allow to control the various compat mechanisms + Use the new config switch in the posix timer code to control the 32bit compat syscall implementation. - Prevent bogus selection of CPU local clocksources which causes an endless reselection loop - Remove the extra kthread in the clocksource code which has no value and just adds another level of indirection - The usual bunch of trivial updates, cleanups and fixlets all over the place - More SPDX conversions * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) clocksource/drivers/mxs_timer: Switch to SPDX identifier clocksource/drivers/timer-imx-tpm: Switch to SPDX identifier clocksource/drivers/timer-imx-gpt: Switch to SPDX identifier clocksource/drivers/timer-imx-gpt: Remove outdated file path clocksource/drivers/arc_timer: Add comments about locking while read GFRC clocksource/drivers/mips-gic-timer: Add pr_fmt and reword pr_* messages clocksource/drivers/sprd: Fix Kconfig dependency clocksource: Move inline keyword to the beginning of function declarations timer_list: Remove unused function pointer typedef timers: Adjust a kernel-doc comment tick: Prefer a lower rating device only if it's CPU local device clocksource: Remove kthread time: Change nanosleep to safe __kernel_* types time: Change types to new y2038 safe __kernel_* types time: Fix get_timespec64() for y2038 safe compat interfaces time: Add new y2038 safe __kernel_timespec posix-timers: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIME time: Introduce CONFIG_COMPAT_32BIT_TIME time: Introduce CONFIG_64BIT_TIME in architectures compat: Enable compat_get/put_timespec64 always ...
| * | | clocksource: Move inline keyword to the beginning of function declarationsMathieu Malaterre2018-05-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The inline keyword was not at the beginning of the function declarations. Fix the following warnings triggered when using W=1: kernel/time/clocksource.c:456:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration] kernel/time/clocksource.c:457:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration] Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180516195943.31924-1-malat@debian.org
| * | | timer_list: Remove unused function pointer typedefChen Lin2018-05-131-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the 'printf_fn_t' typedef as it is not used. Signed-off-by: Chen Lin <chen45464546@163.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: sboyd@kernel.org Cc: john.stultz@linaro.org Link: https://lkml.kernel.org/r/1526053649-24229-1-git-send-email-chen45464546@163.com
| * | | timers: Adjust a kernel-doc commentMauro Carvalho Chehab2018-05-131-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Those three warnings can easily solved by using :: to indicate a code block: ./kernel/time/timer.c:1259: WARNING: Unexpected indentation. ./kernel/time/timer.c:1261: WARNING: Unexpected indentation. ./kernel/time/timer.c:1262: WARNING: Block quote ends without a blank line; unexpected unindent. While here, align the lines at the block. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Stephen Boyd <sboyd@kernel.org> Cc: Linux Doc Mailing List <linux-doc@vger.kernel.org> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/f02e6a0ce27f3b5e33415d92d07a40598904b3ee.1525684985.git.mchehab%2Bsamsung@kernel.org
| * | | tick: Prefer a lower rating device only if it's CPU local deviceSudeep Holla2018-05-131-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Checking the equality of cpumask for both new and old tick device doesn't ensure that it's CPU local device. This will cause issue if a low rating clockevent tick device is registered first followed by the registration of higher rating clockevent tick device. In such case, clockevents_released list will never get emptied as both the devices get selected as preferred one and we will loop forever in clockevents_notify_released. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: https://lkml.kernel.org/r/1525881728-4858-1-git-send-email-sudeep.holla@arm.com
| * | | clocksource: Remove kthreadPeter Zijlstra2018-05-021-21/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The clocksource watchdog uses a work to spawn a kthread to run the watchdog. That is about as silly as it sounds, run the watchdog directly from the work. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Link: https://lkml.kernel.org/r/20180430100344.713862818@infradead.org
| * | | Merge branch 'timers/urgent' into timers/coreThomas Gleixner2018-05-0225-232/+278
| |\ \ \ | | |/ / | |/| | | | | | Pick up urgent fixes to apply dependent cleanup patch
| * | | time: Change nanosleep to safe __kernel_* typesDeepa Dinamani2018-04-193-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change over clock_nanosleep syscalls to use y2038 safe __kernel_timespec times. This will enable changing over of these syscalls to use new y2038 safe syscalls when the architectures define the CONFIG_64BIT_TIME. Note that nanosleep syscall is deprecated and does not have a plan for making it y2038 safe. But, the syscall should work as before on 64 bit machines and on 32 bit machines, the syscall works correctly until y2038 as before using the existing compat syscall version. There is no new syscall for supporting 64 bit time_t on 32 bit architectures. Cc: linux-api@vger.kernel.org Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | | time: Change types to new y2038 safe __kernel_* typesDeepa Dinamani2018-04-192-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change over clock_settime, clock_gettime and clock_getres syscalls to use __kernel_timespec times. This will enable changing over of these syscalls to use new y2038 safe syscalls when the architectures define the CONFIG_64BIT_TIME. Cc: linux-api@vger.kernel.org Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | | time: Fix get_timespec64() for y2038 safe compat interfacesDeepa Dinamani2018-04-191-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | get/put_timespec64() interfaces will eventually be used for conversions between the new y2038 safe struct __kernel_timespec and struct timespec64. The new y2038 safe syscalls have a common entry for native and compat interfaces. On compat interfaces, the high order bits of nanoseconds should be zeroed out. This is because the application code or the libc do not guarantee zeroing of these. If used without zeroing, kernel might be at risk of using timespec values incorrectly. Note that clearing of bits is dependent on CONFIG_64BIT_TIME for now. This is until COMPAT_USE_64BIT_TIME has been handled correctly. x86 will be the first architecture that will use the CONFIG_64BIT_TIME. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | | posix-timers: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIMEDeepa Dinamani2018-04-193-3/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | clock_gettime, clock_settime, clock_getres and clock_nanosleep compat syscalls are also repurposed to provide backward compatibility to support 32 bit time_t on 32 bit systems. Note that nanosleep compat syscall will also be treated the same way as the above syscalls as it shares common handler functions with clock_nanosleep. But, there is no plan to provide y2038 safe solution for nanosleep. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | | compat: Enable compat_get/put_timespec64 alwaysDeepa Dinamani2018-04-192-44/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These functions are used in the repurposed compat syscalls to provide backward compatibility for using 32 bit time_t on 32 bit systems. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* | | | Merge branch 'irq-core-for-linus' of ↵Linus Torvalds2018-06-043-17/+27
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: - Consolidation of softirq pending: The softirq mask and its accessors/mutators have many implementations scattered around many architectures. Most do the same things consisting in a field in a per-cpu struct (often irq_cpustat_t) accessed through per-cpu ops. We can provide instead a generic efficient version that most of them can use. In fact s390 is the only exception because the field is stored in lowcore. - Support for level!?! triggered MSI (ARM) Over the past couple of years, we've seen some SoCs coming up with ways of signalling level interrupts using a new flavor of MSIs, where the MSI controller uses two distinct messages: one that raises a virtual line, and one that lowers it. The target MSI controller is in charge of maintaining the state of the line. This allows for a much simplified HW signal routing (no need to have hundreds of discrete lines to signal level interrupts if you already have a memory bus), but results in a departure from the current idea the kernel has of MSIs. - Support for Meson-AXG GPIO irqchip - Large stm32 irqchip rework (suspend/resume, hierarchical domains) - More SPDX conversions * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) ARM: dts: stm32: Add exti support to stm32mp157 pinctrl ARM: dts: stm32: Add exti support for stm32mp157c pinctrl/stm32: Add irq_eoi for stm32gpio irqchip irqchip/stm32: Add suspend/resume support for hierarchy domain irqchip/stm32: Add stm32mp1 support with hierarchy domain irqchip/stm32: Prepare common functions irqchip/stm32: Add host and driver data structures irqchip/stm32: Add suspend support irqchip/stm32: Add falling pending register support irqchip/stm32: Checkpatch fix irqchip/stm32: Optimizes and cleans up stm32-exti irq_domain irqchip/meson-gpio: Add support for Meson-AXG SoCs dt-bindings: interrupt-controller: New binding for Meson-AXG SoC dt-bindings: interrupt-controller: Fix the double quotes softirq/s390: Move default mutators of overwritten softirq mask to s390 softirq/x86: Switch to generic local_softirq_pending() implementation softirq/sparc: Switch to generic local_softirq_pending() implementation softirq/powerpc: Switch to generic local_softirq_pending() implementation softirq/parisc: Switch to generic local_softirq_pending() implementation softirq/ia64: Switch to generic local_softirq_pending() implementation ...
| * | | | softirq/core: Turn default irq_cpustat_t to standard per-cpuFrederic Weisbecker2018-05-141-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to optimize and consolidate softirq mask accesses, let's convert the default irq_cpustat_t implementation to per-CPU standard API. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David S. Miller <davem@davemloft.net> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Rich Felker <dalias@libc.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/1525786706-22846-5-git-send-email-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | Merge tag 'v4.17-rc5' into irq/core, to pick up fixesIngo Molnar2018-05-1435-362/+409
| |\ \ \ \ | | | |_|/ | | |/| | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | genirq/msi: Allow level-triggered MSIs to be exposed by MSI providersMarc Zyngier2018-05-131-9/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So far, MSIs have been used to signal edge-triggered interrupts, as a write is a good model for an edge (you can't "unwrite" something). On the other hand, routing zillions of wires in an SoC because you need level interrupts is a bit extreme. People have come up with a variety of schemes to support this, which involves sending two messages: one to signal the interrupt, and one to clear it. Since the kernel cannot represent this, we've ended up with side-band mechanisms that are pretty awful. Instead, let's acknoledge the requirement, and ensure that, under the right circumstances, the irq_compose_msg and irq_write_msg can take as a parameter an array of two messages instead of a pointer to a single one. We also add some checking that the compose method only clobbers the second message if the MSI domain has been created with the MSI_FLAG_LEVEL_CAPABLE flags. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <robh@kernel.org> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Cc: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lkml.kernel.org/r/20180508121438.11301-2-marc.zyngier@arm.com
| * | | | genirq/irq_sim: Remove the license boilerplateBartosz Golaszewski2018-04-261-6/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is the SPDX license identifier now in the irq simulator. Remove the license boilerplate. While at it: update the copyright notice, since I did some changes in 2018. Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180426200747.8344-1-brgl@bgdev.pl
* | | | | Merge branch 'sched-core-for-linus' of ↵Linus Torvalds2018-06-044-68/+111
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: - power-aware scheduling improvements (Patrick Bellasi) - NUMA balancing improvements (Mel Gorman) - vCPU scheduling fixes (Rohit Jain) * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/fair: Update util_est before updating schedutil sched/cpufreq: Modify aggregate utilization to always include blocked FAIR utilization sched/deadline/Documentation: Add overrun signal and GRUB-PA documentation sched/core: Distinguish between idle_cpu() calls based on desired effect, introduce available_idle_cpu() sched/wait: Include <linux/wait.h> in <linux/swait.h> sched/numa: Stagger NUMA balancing scan periods for new threads sched/core: Don't schedule threads on pre-empted vCPUs sched/fair: Avoid calling sync_entity_load_avg() unnecessarily sched/fair: Rearrange select_task_rq_fair() to optimize it
| * | | | | sched/fair: Update util_est before updating schedutilPatrick Bellasi2018-05-251-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a task is enqueued the estimated utilization of a CPU is updated to better support the selection of the required frequency. However, schedutil is (implicitly) updated by update_load_avg() which always happens before util_est_{en,de}queue(), thus potentially introducing a latency between estimated utilization updates and frequency selections. Let's update util_est at the beginning of enqueue_task_fair(), which will ensure that all schedutil updates will see the most updated estimated utilization value for a CPU. Reported-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Vincent Guittot <vincent.guittot@linaro.org> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Joel Fernandes <joelaf@google.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten Rasmussen <morten.rasmussen@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com> Cc: Steve Muckle <smuckle@google.com> Fixes: 7f65ea42eb00 ("sched/fair: Add util_est on top of PELT") Link: http://lkml.kernel.org/r/20180524141023.13765-3-patrick.bellasi@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/cpufreq: Modify aggregate utilization to always include blocked FAIR ↵Patrick Bellasi2018-05-251-9/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | utilization Since the refactoring introduced by: commit 8f111bc357aa ("cpufreq/schedutil: Rewrite CPUFREQ_RT support") we aggregate FAIR utilization only if this class has runnable tasks. This was mainly due to avoid the risk to stay on an high frequency just because of the blocked utilization of a CPU not being properly decayed while the CPU was idle. However, since: commit 31e77c93e432 ("sched/fair: Update blocked load when newly idle") the FAIR blocked utilization is properly decayed also for IDLE CPUs. This allows us to use the FAIR blocked utilization as a safe mechanism to gracefully reduce the frequency only if no FAIR tasks show up on a CPU for a reasonable period of time. Moreover, we also reduce the frequency drops of CPUs running periodic tasks which, depending on the task periodicity and the time required for a frequency switch, was increasing the chances to introduce some undesirable performance variations. Reported-by: Vincent Guittot <vincent.guittot@linaro.org> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Vincent Guittot <vincent.guittot@linaro.org> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Joel Fernandes <joelaf@google.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten Rasmussen <morten.rasmussen@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com> Cc: Steve Muckle <smuckle@google.com> Link: http://lkml.kernel.org/r/20180524141023.13765-2-patrick.bellasi@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | Merge branch 'sched/urgent' into sched/core, to pick up fixesIngo Molnar2018-05-2514-76/+223
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | sched/core: Distinguish between idle_cpu() calls based on desired effect, ↵Rohit Jain2018-05-142-10/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | introduce available_idle_cpu() In the following commit: 247f2f6f3c70 ("sched/core: Don't schedule threads on pre-empted vCPUs") ... we distinguish between idle_cpu() when the vCPU is not running for scheduling threads. However, the idle_cpu() function is used in other places for actually checking whether the state of the CPU is idle or not. Hence split the use of that function based on the desired return value, by introducing the available_idle_cpu() function. This fixes a (slight) regression in that initial vCPU commit, because some code paths (like the load-balancer) don't care and shouldn't care if the vCPU is preempted or not, they just want to know if there's any tasks on the CPU. Signed-off-by: Rohit Jain <rohit.k.jain@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dhaval.giani@oracle.com Cc: linux-kernel@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: steven.sistare@oracle.com Cc: subhra.mazumdar@oracle.com Link: http://lkml.kernel.org/r/1525883988-10356-1-git-send-email-rohit.k.jain@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | sched/numa: Stagger NUMA balancing scan periods for new threadsMel Gorman2018-05-143-21/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Threads share an address space and each can change the protections of the same address space to trap NUMA faults. This is redundant and potentially counter-productive as any thread doing the update will suffice. Potentially only one thread is required but that thread may be idle or it may not have any locality concerns and pick an unsuitable scan rate. This patch uses independent scan period but they are staggered based on the number of address space users when the thread is created. The intent is that threads will avoid scanning at the same time and have a chance to adapt their scan rate later if necessary. This reduces the total scan activity early in the lifetime of the threads. The different in headline performance across a range of machines and workloads is marginal but the system CPU usage is reduced as well as overall scan activity. The following is the time reported by NAS Parallel Benchmark using unbound openmp threads and a D size class: 4.17.0-rc1 4.17.0-rc1 vanilla stagger-v1r1 Time bt.D 442.77 ( 0.00%) 419.70 ( 5.21%) Time cg.D 171.90 ( 0.00%) 180.85 ( -5.21%) Time ep.D 33.10 ( 0.00%) 32.90 ( 0.60%) Time is.D 9.59 ( 0.00%) 9.42 ( 1.77%) Time lu.D 306.75 ( 0.00%) 304.65 ( 0.68%) Time mg.D 54.56 ( 0.00%) 52.38 ( 4.00%) Time sp.D 1020.03 ( 0.00%) 903.77 ( 11.40%) Time ua.D 400.58 ( 0.00%) 386.49 ( 3.52%) Note it's not a universal win but we have no prior knowledge of which thread matters but the number of threads created often exceeds the size of the node when the threads are not bound. However, there is a reducation of overall system CPU usage: 4.17.0-rc1 4.17.0-rc1 vanilla stagger-v1r1 sys-time-bt.D 48.78 ( 0.00%) 48.22 ( 1.15%) sys-time-cg.D 25.31 ( 0.00%) 26.63 ( -5.22%) sys-time-ep.D 1.65 ( 0.00%) 0.62 ( 62.42%) sys-time-is.D 40.05 ( 0.00%) 24.45 ( 38.95%) sys-time-lu.D 37.55 ( 0.00%) 29.02 ( 22.72%) sys-time-mg.D 47.52 ( 0.00%) 34.92 ( 26.52%) sys-time-sp.D 119.01 ( 0.00%) 109.05 ( 8.37%) sys-time-ua.D 51.52 ( 0.00%) 45.13 ( 12.40%) NUMA scan activity is also reduced: NUMA alloc local 1042828 1342670 NUMA base PTE updates 140481138 93577468 NUMA huge PMD updates 272171 180766 NUMA page range updates 279832690 186129660 NUMA hint faults 1395972 1193897 NUMA hint local faults 877925 855053 NUMA hint local percent 62 71 NUMA pages migrated 12057909 9158023 Similar observations are made for other thread-intensive workloads. System CPU usage is lower even though the headline gains in performance tend to be small. For example, specjbb 2005 shows almost no difference in performance but scan activity is reduced by a third on a 4-socket box. I didn't find a workload (thread intensive or otherwise) that suffered badly. Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/20180504154109.mvrha2qo5wdl65vr@techsingularity.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | Merge tag 'v4.17-rc5' into sched/core, to pick up fixes and dependenciesIngo Molnar2018-05-1414-131/+166
| |\ \ \ \ \ \ | | | |_|/ / / | | |/| | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | sched/core: Don't schedule threads on pre-empted vCPUsRohit Jain2018-05-041-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In paravirt configurations today, spinlocks figure out whether a vCPU is running to determine whether or not spinlock should bother spinning. We can use the same logic to prioritize CPUs when scheduling threads. If a vCPU has been pre-empted, it will incur the extra cost of VMENTER and the time it actually spends to be running on the host CPU. If we had other vCPUs which were actually running on the host CPU and idle we should schedule threads there. Performance numbers: Note: With patch is referred to as Paravirt in the following and without patch is referred to as Base. 1) When only 1 VM is running: a) Hackbench test on KVM 8 vCPUs, 10,000 loops (lower is better): +-------+-----------------+----------------+ |Number |Paravirt |Base | |of +---------+-------+-------+--------+ |Threads|Average |Std Dev|Average| Std Dev| +-------+---------+-------+-------+--------+ |1 |1.817 |0.076 |1.721 | 0.067 | |2 |3.467 |0.120 |3.468 | 0.074 | |4 |6.266 |0.035 |6.314 | 0.068 | |8 |11.437 |0.105 |11.418 | 0.132 | |16 |21.862 |0.167 |22.161 | 0.129 | |25 |33.341 |0.326 |33.692 | 0.147 | +-------+---------+-------+-------+--------+ 2) When two VMs are running with same CPU affinities: a) tbench test on VM 8 cpus Base: VM1: Throughput 220.59 MB/sec 1 clients 1 procs max_latency=12.872 ms Throughput 448.716 MB/sec 2 clients 2 procs max_latency=7.555 ms Throughput 861.009 MB/sec 4 clients 4 procs max_latency=49.501 ms Throughput 1261.81 MB/sec 7 clients 7 procs max_latency=76.990 ms VM2: Throughput 219.937 MB/sec 1 clients 1 procs max_latency=12.517 ms Throughput 470.99 MB/sec 2 clients 2 procs max_latency=12.419 ms Throughput 841.299 MB/sec 4 clients 4 procs max_latency=37.043 ms Throughput 1240.78 MB/sec 7 clients 7 procs max_latency=77.489 ms Paravirt: VM1: Throughput 222.572 MB/sec 1 clients 1 procs max_latency=7.057 ms Throughput 485.993 MB/sec 2 clients 2 procs max_latency=26.049 ms Throughput 947.095 MB/sec 4 clients 4 procs max_latency=45.338 ms Throughput 1364.26 MB/sec 7 clients 7 procs max_latency=145.124 ms VM2: Throughput 224.128 MB/sec 1 clients 1 procs max_latency=4.564 ms Throughput 501.878 MB/sec 2 clients 2 procs max_latency=11.061 ms Throughput 965.455 MB/sec 4 clients 4 procs max_latency=45.370 ms Throughput 1359.08 MB/sec 7 clients 7 procs max_latency=168.053 ms b) Hackbench with 4 fd 1,000,000 loops +-------+--------------------------------------+----------------------------------------+ |Number |Paravirt |Base | |of +----------+--------+---------+--------+----------+--------+---------+----------+ |Threads|Average1 |Std Dev1|Average2 | Std Dev|Average1 |Std Dev1|Average2 | Std Dev 2| +-------+----------+--------+---------+--------+----------+--------+---------+----------+ | 1 | 3.748 | 0.620 | 3.576 | 0.432 | 4.006 | 0.395 | 3.446 | 0.787 | +-------+----------+--------+---------+--------+----------+--------+---------+----------+ Note that this test was run just to show the interference effect over-subscription can have in baseline c) schbench results with 2 message groups on 8 vCPU VMs +-----------+-------+---------------+--------------+------------+ | | | Paravirt | Base | | +-----------+-------+-------+-------+-------+------+------------+ | |Threads| VM1 | VM2 | VM1 | VM2 |%Improvement| +-----------+-------+-------+-------+-------+------+------------+ |50.0000th | 1 | 52 | 53 | 58 | 54 | +6.25% | |75.0000th | 1 | 69 | 61 | 83 | 59 | +8.45% | |90.0000th | 1 | 80 | 80 | 89 | 83 | +6.98% | |95.0000th | 1 | 83 | 83 | 93 | 87 | +7.78% | |*99.0000th | 1 | 92 | 94 | 99 | 97 | +5.10% | |99.5000th | 1 | 95 | 100 | 102 | 103 | +4.88% | |99.9000th | 1 | 107 | 123 | 105 | 203 | +25.32% | +-----------+-------+-------+-------+-------+------+------------+ |50.0000th | 2 | 56 | 62 | 67 | 59 | +6.35% | |75.0000th | 2 | 69 | 75 | 80 | 71 | +4.64% | |90.0000th | 2 | 80 | 82 | 90 | 81 | +5.26% | |95.0000th | 2 | 85 | 87 | 97 | 91 | +8.51% | |*99.0000th | 2 | 98 | 99 | 107 | 109 | +8.79% | |99.5000th | 2 | 107 | 105 | 109 | 116 | +5.78% | |99.9000th | 2 | 9968 | 609 | 875 | 3116 | -165.02% | +-----------+-------+-------+-------+-------+------+------------+ |50.0000th | 4 | 78 | 77 | 78 | 79 | +1.27% | |75.0000th | 4 | 98 | 106 | 100 | 104 | 0.00% | |90.0000th | 4 | 987 | 1001 | 995 | 1015 | +1.09% | |95.0000th | 4 | 4136 | 5368 | 5752 | 5192 | +13.16% | |*99.0000th | 4 | 11632 | 11344 | 11024| 10736| -5.59% | |99.5000th | 4 | 12624 | 13040 | 12720| 12144| -3.22% | |99.9000th | 4 | 13168 | 18912 | 14992| 17824| +2.24% | +-----------+-------+-------+-------+-------+------+------------+ Note: Improvement is measured for (VM1+VM2) Signed-off-by: Rohit Jain <rohit.k.jain@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dhaval.giani@oracle.com Cc: matt@codeblueprint.co.uk Cc: steven.sistare@oracle.com Cc: subhra.mazumdar@oracle.com Link: http://lkml.kernel.org/r/1525294330-7759-1-git-send-email-rohit.k.jain@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | sched/fair: Avoid calling sync_entity_load_avg() unnecessarilyViresh Kumar2018-05-041-9/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Call sync_entity_load_avg() directly from find_idlest_cpu() instead of select_task_rq_fair(), as that's where we need to use task's utilization value. And call sync_entity_load_avg() only after making sure sched domain spans over one of the allowed CPUs for the task. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Link: http://lkml.kernel.org/r/cd019d1753824c81130eae7b43e2bbcec47cc1ad.1524738578.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | sched/fair: Rearrange select_task_rq_fair() to optimize itViresh Kumar2018-05-041-21/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rearrange select_task_rq_fair() a bit to avoid executing some conditional statements in few specific code-paths. That gets rid of the goto as well. This shouldn't result in any functional changes. Tested-by: Rohit Jain <rohit.k.jain@oracle.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Link: http://lkml.kernel.org/r/20831b8d237bf3a20e4e328286f678b425ff04c9.1524738578.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | | | | Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2018-06-041-22/+22
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "Kernel side changes: - x86 Intel uncore driver cleanups and enhancements (Kan Liang) - group scheduling and other fixes (Song Liu - store frame pointer in the sample traces for better profiling (Alexey Budankov) - compat fixes/enhancements (Eugene Syromiatnikov) Tooling side changes, which you can build and install in a single step via: make -C tools/perf clean install perf annotate: - Support 'perf annotate --group' for non-explicit recorded event "groups", showing multiple columns, one for each event, just like when dealing with explicit event groups (those enclosed with {}) (Jin Yao) - Record min/max LBR cycles (>= Skylake) and add 'perf annotate' TUI hotkey to show it (c) (Jin Yao) perf bpf: - Add infrastructure to help in writing eBPF C programs to be used with '-e name.c' type events in tools such as 'record' and 'trace', with headers for common constructs and an examples directory that will get populated as we add more such helpers and the 'perf bpf' (Arnaldo Carvalho de Melo) perf stat: - Display time in precision based on std deviation (Jiri Olsa) - Add --table option to display time of each run (Jiri Olsa) - Display length strings of each run for --table option (Jiri Olsa) perf buildid-cache: - Add --list and --purge-all options (Ravi Bangoria) perf test: - Let 'perf test list' display subtests (Hendrik Brueckner) perf pti: - Create extra kernel maps to help in decoding samples in x86 PTI entry trampolines (Adrian Hunter) - Copy x86 PTI entry trampoline sections in the kcore copy used for annotation and intel_pt CPU traces decoding (Adrian Hunter) ... and a lot of other fixes, enhancements and cleanups I did not list, see the shortlog and git log for details" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (111 commits) perf/x86/intel/uncore: Clean up client IMC uncore perf/x86/intel/uncore: Expose uncore_pmu_event*() functions perf/x86/intel/uncore: Support IIO free-running counters on SKX perf/x86/intel/uncore: Add infrastructure for free running counters perf/x86/intel/uncore: Add new data structures for free running counters perf/x86/intel/uncore: Correct fixed counter index check in generic code perf/x86/intel/uncore: Correct fixed counter index check for NHM perf/x86/intel/uncore: Introduce customized event_read() for client IMC uncore perf/x86: Store user space frame-pointer value on a sample perf/core: Wire up compat PERF_EVENT_IOC_QUERY_BPF, PERF_EVENT_IOC_MODIFY_ATTRIBUTES perf/core: Fix bad use of igrab() perf/core: Fix group scheduling with mixed hw and sw events perf kcore_copy: Amend the offset of sections that remap kernel text perf kcore_copy: Copy x86 PTI entry trampoline sections perf kcore_copy: Get rid of kernel_map perf kcore_copy: Iterate phdrs perf kcore_copy: Layout sections perf kcore_copy: Calculate offset from phnum perf kcore_copy: Keep a count of phdrs perf kcore_copy: Keep phdr data in a list ...
| * \ \ \ \ \ \ Merge branch 'linus' into perf/core, to pick up fixesIngo Molnar2018-05-314-27/+72
| |\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | perf/core: Wire up compat PERF_EVENT_IOC_QUERY_BPF, ↵Eugene Syromiatnikov2018-05-251-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PERF_EVENT_IOC_MODIFY_ATTRIBUTES Since pointer size is different in compat, and switching in _perf_ioctl is done using exact ioctl numbers, all new ioctl numbers that use pointer should be added to perf_compat_ioctl for _IOC_SIZE fixup before passing to perf_ioctl routine (this shouldn't be needed if semantics of the size argument of _IO* macros was honored). Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/20180521123420.GA24291@asgard.redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | perf/core: Fix bad use of igrab()Song Liu2018-05-251-12/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Miklos reported and suggested: "This pattern repeats two times in trace_uprobe.c and in kernel/events/core.c as well: ret = kern_path(filename, LOOKUP_FOLLOW, &path); if (ret) goto fail_address_parse; inode = igrab(d_inode(path.dentry)); path_put(&path); And it's wrong. You can only hold a reference to the inode if you have an active ref to the superblock as well (which is normally through path.mnt) or holding s_umount. This way unmounting the containing filesystem while the tracepoint is active will give you the "VFS: Busy inodes after unmount..." message and a crash when the inode is finally put. Solution: store path instead of inode." This patch fixes the issue in kernel/event/core.c. Reviewed-and-tested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reported-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <kernel-team@fb.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 375637bc5249 ("perf/core: Introduce address range filtering") Link: http://lkml.kernel.org/r/20180418062907.3210386-2-songliubraving@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | perf/core: Fix group scheduling with mixed hw and sw eventsSong Liu2018-05-251-10/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When hw and sw events are mixed in the same group, they are all attached to the hw perf_event_context. This sometimes requires moving group of perf_event to a different context. We found a bug in how the kernel handles this, for example if we do: perf stat -e '{faults,ref-cycles,faults}' -I 1000 1.005591180 1,297 faults 1.005591180 457,476,576 ref-cycles 1.005591180 <not supported> faults First, sw event "faults" is attached to the sw context, and becomes the group leader. Then, hw event "ref-cycles" is attached, so both events are moved to the hw context. Last, another sw "faults" tries to attach, but it fails because of mismatch between the new target ctx (from sw pmu) and the group_leader's ctx (hw context, same as ref-cycles). The broken condition is: group_leader is sw event; group_leader is on hw context; add a sw event to the group. Fix this scenario by checking group_leader's context (instead of just event type). If group_leader is on hw context, use the ->pmu of this context to look up context for the new event. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <kernel-team@fb.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: b04243ef7006 ("perf: Complete software pmu grouping") Link: http://lkml.kernel.org/r/20180503194716.162815-1-songliubraving@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | | | | | | Merge branch 'locking-core-for-linus' of ↵Linus Torvalds2018-06-049-256/+198
|\ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: - Lots of tidying up changes all across the map for Linux's formal memory/locking-model tooling, by Alan Stern, Akira Yokosawa, Andrea Parri, Paul E. McKenney and SeongJae Park. Notable changes beyond an overall update in the tooling itself is the tidying up of spin_is_locked() semantics, which spills over into the kernel proper as well. - qspinlock improvements: the locking algorithm now guarantees forward progress whereas the previous implementation in mainline could starve threads indefinitely in cmpxchg() loops. Also other related cleanups to the qspinlock code (Will Deacon) - misc smaller improvements, cleanups and fixes all across the locking subsystem * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits) locking/rwsem: Simplify the is-owner-spinnable checks tools/memory-model: Add reference for 'Simplifying ARM concurrency' tools/memory-model: Update ASPLOS information MAINTAINERS, tools/memory-model: Update e-mail address for Andrea Parri tools/memory-model: Fix coding style in 'lock.cat' tools/memory-model: Remove out-of-date comments and code from lock.cat tools/memory-model: Improve mixed-access checking in lock.cat tools/memory-model: Improve comments in lock.cat tools/memory-model: Remove duplicated code from lock.cat tools/memory-model: Flag "cumulativity" and "propagation" tests tools/memory-model: Add model support for spin_is_locked() tools/memory-model: Add scripts to test memory model tools/memory-model: Fix coding style in 'linux-kernel.def' tools/memory-model: Model 'smp_store_mb()' tools/memory-order: Update the cheat-sheet to show that smp_mb__after_atomic() orders later RMW operations tools/memory-order: Improve key for SELF and SV tools/memory-model: Fix cheat sheet typo tools/memory-model: Update required version of herdtools7 tools/memory-model: Redefine rb in terms of rcu-fence tools/memory-model: Rename link and rcu-path to rcu-link and rb ...
| * | | | | | | | | locking/rwsem: Simplify the is-owner-spinnable checksOleg Nesterov2018-05-251-12/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the trivial owner_on_cpu() helper for rwsem_can_spin_on_owner() and rwsem_spin_on_owner(), it also allows to make rwsem_can_spin_on_owner() a bit more clear. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Waiman Long <longman@redhat.com> Cc: Amir Goldstein <amir73il@gmail.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Jan Kara <jack@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Theodore Y. Ts'o <tytso@mit.edu> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180518165534.GA22348@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | | Merge branch 'linus' into locking/core, to pick up fixesIngo Molnar2018-05-2512-71/+220
| |\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | | Merge tag 'v4.17-rc5' into locking/core, to pick up fixesIngo Molnar2018-05-1515-164/+164
| |\ \ \ \ \ \ \ \ \ | | | |_|_|/ / / / / | | |/| | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | | locking/lockdep: Move sanity check to inside lockdep_print_held_locks()Tetsuo Handa2018-05-141-16/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Calling lockdep_print_held_locks() on a running thread is considered unsafe. Since all callers should follow that rule and the sanity check is not heavy, this patch moves the sanity check to inside lockdep_print_held_locks(). As a side effect of this patch, the number of locks held by running threads will be printed as well. This change will be preferable when we want to know which threads might be relevant to a problem but are unable to print any clues because that thread is running. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1523011279-8206-2-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | | locking/lockdep: Use for_each_process_thread() for debug_show_all_locks()Tetsuo Handa2018-05-141-35/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | debug_show_all_locks() tries to grab the tasklist_lock for two seconds, but calling while_each_thread() without tasklist_lock held is not safe. See the following commit for more information: 4449a51a7c281602 ("vm_is_stack: use for_each_thread() rather then buggy while_each_thread()") Change debug_show_all_locks() from "do_each_thread()/while_each_thread() with possibility of missing tasklist_lock" to "for_each_process_thread() with RCU", and add a call to touch_all_softlockup_watchdogs() like show_state_filter() does. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1523011279-8206-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | | Merge branch 'linus' into locking/core, to pick up fixesIngo Molnar2018-05-0518-166/+186
| |\ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | | | locking/mutex: Optimize __mutex_trylock_fast()Peter Zijlstra2018-05-041-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use try_cmpxchg to avoid the pointless TEST instruction.. And add the (missing) atomic_long_try_cmpxchg*() wrappery. On x86_64 this gives: 0000000000000710 <mutex_lock>: 0000000000000710 <mutex_lock>: 710: 65 48 8b 14 25 00 00 mov %gs:0x0,%rdx 710: 65 48 8b 14 25 00 00 mov %gs:0x0,%rdx 717: 00 00 717: 00 00 715: R_X86_64_32S current_task 715: R_X86_64_32S current_task 719: 31 c0 xor %eax,%eax 719: 31 c0 xor %eax,%eax 71b: f0 48 0f b1 17 lock cmpxchg %rdx,(%rdi) 71b: f0 48 0f b1 17 lock cmpxchg %rdx,(%rdi) 720: 48 85 c0 test %rax,%rax 720: 75 02 jne 724 <mutex_lock+0x14> 723: 75 02 jne 727 <mutex_lock+0x17> 722: f3 c3 repz retq 725: f3 c3 repz retq 724: eb da jmp 700 <__mutex_lock_slowpath> 727: eb d7 jmp 700 <__mutex_lock_slowpath> 726: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1) 729: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 72d: 00 00 00 On ARM64 this gives: 000000000000638 <mutex_lock>: 0000000000000638 <mutex_lock>: 638: d5384101 mrs x1, sp_el0 638: d5384101 mrs x1, sp_el0 63c: d2800002 mov x2, #0x0 63c: d2800002 mov x2, #0x0 640: f9800011 prfm pstl1strm, [x0] 640: f9800011 prfm pstl1strm, [x0] 644: c85ffc03 ldaxr x3, [x0] 644: c85ffc03 ldaxr x3, [x0] 648: ca020064 eor x4, x3, x2 648: ca020064 eor x4, x3, x2 64c: b5000064 cbnz x4, 658 <mutex_lock+0x20> 64c: b5000064 cbnz x4, 658 <mutex_lock+0x20> 650: c8047c01 stxr w4, x1, [x0] 650: c8047c01 stxr w4, x1, [x0] 654: 35ffff84 cbnz w4, 644 <mutex_lock+0xc> 654: 35ffff84 cbnz w4, 644 <mutex_lock+0xc> 658: b40000c3 cbz x3, 670 <mutex_lock+0x38> 658: b5000043 cbnz x3, 660 <mutex_lock+0x28> 65c: a9bf7bfd stp x29, x30, [sp,#-16]! 65c: d65f03c0 ret 660: 910003fd mov x29, sp 660: a9bf7bfd stp x29, x30, [sp,#-16]! 664: 97ffffef bl 620 <__mutex_lock_slowpath> 664: 910003fd mov x29, sp 668: a8c17bfd ldp x29, x30, [sp],#16 668: 97ffffee bl 620 <__mutex_lock_slowpath> 66c: d65f03c0 ret 66c: a8c17bfd ldp x29, x30, [sp],#16 670: d65f03c0 ret 670: d65f03c0 ret Reported-by: Matthew Wilcox <mawilcox@microsoft.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | | | stop_machine: Use raw spinlocksThomas Gleixner2018-04-271-12/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use raw-locks in stop_machine() to allow locking in irq-off and preempt-disabled regions on -RT. This also documents the possible locking context in general. [bigeasy: update patch description.] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lkml.kernel.org/r/20180423191635.6014-1-bigeasy@linutronix.de
| * | | | | | | | | | delayacct: Use raw_spinlocksSebastian Andrzej Siewior2018-04-271-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | try_to_wake_up() might invoke delayacct_blkio_end() while holding the pi_lock (which is a raw_spinlock_t). delayacct_blkio_end() acquires task_delay_info.lock which is a spinlock_t. This causes a might sleep splat on -RT where non raw spinlocks are converted to 'sleeping' spinlocks. task_delay_info.lock is only held for a short amount of time so it's not a problem latency wise to make convert it to a raw spinlock. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Balbir Singh <bsingharora@gmail.com> Link: https://lkml.kernel.org/r/20180423161024.6710-1-bigeasy@linutronix.de
| * | | | | | | | | | locking/qspinlock: Remove duplicate clear_pending() function from PV codeWill Deacon2018-04-271-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The native clear_pending() function is identical to the PV version, so the latter can simply be removed. This fixes the build for systems with >= 16K CPUs using the PV lock implementation. Reported-by: Waiman Long <longman@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boqun.feng@gmail.com Cc: linux-arm-kernel@lists.infradead.org Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/20180427101619.GB21705@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | | | locking/qspinlock: Add stat tracking for pending vs. slowpathWaiman Long2018-04-273-12/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the qspinlock_stat code tracks only statistical counts in the PV qspinlock code. However, it may also be useful to track the number of locking operations done via the pending code vs. the MCS lock queue slowpath for the non-PV case. The qspinlock stat code is modified to do that. The stat counter pv_lock_slowpath is renamed to lock_slowpath so that it can be used by both the PV and non-PV cases. Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Waiman Long <longman@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boqun.feng@gmail.com Cc: linux-arm-kernel@lists.infradead.org Cc: paulmck@linux.vnet.ibm.com Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1524738868-31318-14-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>