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* Merge tag 'pm-4.10-rc1' of ↵Linus Torvalds2016-12-133-86/+209
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "Again, cpufreq gets more changes than the other parts this time (one new driver, one old driver less, a bunch of enhancements of the existing code, new CPU IDs, fixes, cleanups) There also are some changes in cpuidle (idle injection rework, a couple of new CPU IDs, online/offline rework in intel_idle, fixes and cleanups), in the generic power domains framework (mostly related to supporting power domains containing CPUs), and in the Operating Performance Points (OPP) library (mostly related to supporting devices with multiple voltage regulators) In addition to that, the system sleep state selection interface is modified to make it easier for distributions with unchanged user space to support suspend-to-idle as the default system suspend method, some issues are fixed in the PM core, the latency tolerance PM QoS framework is improved a bit, the Intel RAPL power capping driver is cleaned up and there are some fixes and cleanups in the devfreq subsystem Specifics: - New cpufreq driver for Broadcom STB SoCs and a Device Tree binding for it (Markus Mayer) - Support for ARM Integrator/AP and Integrator/CP in the generic DT cpufreq driver and elimination of the old Integrator cpufreq driver (Linus Walleij) - Support for the zx296718, r8a7743 and r8a7745, Socionext UniPhier, and PXA SoCs in the the generic DT cpufreq driver (Baoyou Xie, Geert Uytterhoeven, Masahiro Yamada, Robert Jarzmik) - cpufreq core fix to eliminate races that may lead to using inactive policy objects and related cleanups (Rafael Wysocki) - cpufreq schedutil governor update to make it use SCHED_FIFO kernel threads (instead of regular workqueues) for doing delayed work (to reduce the response latency in some cases) and related cleanups (Viresh Kumar) - New cpufreq sysfs attribute for resetting statistics (Markus Mayer) - cpufreq governors fixes and cleanups (Chen Yu, Stratos Karafotis, Viresh Kumar) - Support for using generic cpufreq governors in the intel_pstate driver (Rafael Wysocki) - Support for per-logical-CPU P-state limits and the EPP/EPB (Energy Performance Preference/Energy Performance Bias) knobs in the intel_pstate driver (Srinivas Pandruvada) - New CPU ID for Knights Mill in intel_pstate (Piotr Luc) - intel_pstate driver modification to use the P-state selection algorithm based on CPU load on platforms with the system profile in the ACPI tables set to "mobile" (Srinivas Pandruvada) - intel_pstate driver cleanups (Arnd Bergmann, Rafael Wysocki, Srinivas Pandruvada) - cpufreq powernv driver updates including fast switching support (for the schedutil governor), fixes and cleanus (Akshay Adiga, Andrew Donnellan, Denis Kirjanov) - acpi-cpufreq driver rework to switch it over to the new CPU offline/online state machine (Sebastian Andrzej Siewior) - Assorted cleanups in cpufreq drivers (Wei Yongjun, Prashanth Prakash) - Idle injection rework (to make it use the regular idle path instead of a home-grown custom one) and related powerclamp thermal driver updates (Peter Zijlstra, Jacob Pan, Petr Mladek, Sebastian Andrzej Siewior) - New CPU IDs for Atom Z34xx and Knights Mill in intel_idle (Andy Shevchenko, Piotr Luc) - intel_idle driver cleanups and switch over to using the new CPU offline/online state machine (Anna-Maria Gleixner, Sebastian Andrzej Siewior) - cpuidle DT driver update to support suspend-to-idle properly (Sudeep Holla) - cpuidle core cleanups and misc updates (Daniel Lezcano, Pan Bian, Rafael Wysocki) - Preliminary support for power domains including CPUs in the generic power domains (genpd) framework and related DT bindings (Lina Iyer) - Assorted fixes and cleanups in the generic power domains (genpd) framework (Colin Ian King, Dan Carpenter, Geert Uytterhoeven) - Preliminary support for devices with multiple voltage regulators and related fixes and cleanups in the Operating Performance Points (OPP) library (Viresh Kumar, Masahiro Yamada, Stephen Boyd) - System sleep state selection interface rework to make it easier to support suspend-to-idle as the default system suspend method (Rafael Wysocki) - PM core fixes and cleanups, mostly related to the interactions between the system suspend and runtime PM frameworks (Ulf Hansson, Sahitya Tummala, Tony Lindgren) - Latency tolerance PM QoS framework imorovements (Andrew Lutomirski) - New Knights Mill CPU ID for the Intel RAPL power capping driver (Piotr Luc) - Intel RAPL power capping driver fixes, cleanups and switch over to using the new CPU offline/online state machine (Jacob Pan, Thomas Gleixner, Sebastian Andrzej Siewior) - Fixes and cleanups in the exynos-ppmu, exynos-nocp, rk3399_dmc, rockchip-dfi devfreq drivers and the devfreq core (Axel Lin, Chanwoo Choi, Javier Martinez Canillas, MyungJoo Ham, Viresh Kumar) - Fix for false-positive KASAN warnings during resume from ACPI S3 (suspend-to-RAM) on x86 (Josh Poimboeuf) - Memory map verification during resume from hibernation on x86 to ensure a consistent address space layout (Chen Yu) - Wakeup sources debugging enhancement (Xing Wei) - rockchip-io AVS driver cleanup (Shawn Lin)" * tag 'pm-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (127 commits) devfreq: rk3399_dmc: Don't use OPP structures outside of RCU locks devfreq: rk3399_dmc: Remove dangling rcu_read_unlock() devfreq: exynos: Don't use OPP structures outside of RCU locks Documentation: intel_pstate: Document HWP energy/performance hints cpufreq: intel_pstate: Support for energy performance hints with HWP cpufreq: intel_pstate: Add locking around HWP requests PM / sleep: Print active wakeup sources when blocking on wakeup_count reads PM / core: Fix bug in the error handling of async suspend PM / wakeirq: Fix dedicated wakeirq for drivers not using autosuspend PM / Domains: Fix compatible for domain idle state PM / OPP: Don't WARN on multiple calls to dev_pm_opp_set_regulators() PM / OPP: Allow platform specific custom set_opp() callbacks PM / OPP: Separate out _generic_set_opp() PM / OPP: Add infrastructure to manage multiple regulators PM / OPP: Pass struct dev_pm_opp_supply to _set_opp_voltage() PM / OPP: Manage supply's voltage/current in a separate structure PM / OPP: Don't use OPP structure outside of rcu protected section PM / OPP: Reword binding supporting multiple regulators per device PM / OPP: Fix incorrect cpu-supply property in binding cpuidle: Add a kerneldoc comment to cpuidle_use_deepest_state() ..
| * Merge branch 'pm-cpuidle'Rafael J. Wysocki2016-12-122-66/+110
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * pm-cpuidle: cpuidle: Add a kerneldoc comment to cpuidle_use_deepest_state() cpuidle: fix improper return value on error intel_idle: Convert to hotplug state machine intel_idle: Remove superfluous SMP fuction call MAINTAINERS: Add Jacob Pan as a new intel_idle maintainer MAINTAINERS: Add bug tracking system location entries for cpuidle x86/intel_idle: Add Knights Mill CPUID x86/intel_idle: Add CPU model 0x4a (Atom Z34xx series) thermal/intel_powerclamp: stop sched tick in forced idle thermal/intel_powerclamp: Convert to CPU hotplug state thermal/intel_powerclamp: Convert the kthread to kthread worker API thermal/intel_powerclamp: Remove duplicated code that starts the kthread sched/idle: Add support for tasks that inject idle cpuidle: Allow enforcing deepest idle state selection cpuidle/powernv: staticise powernv_idle_driver cpuidle: dt: assign ->enter_freeze to same as ->enter callback function cpuidle: governors: Remove remaining old module code
| | * Merge back earlier cpuidle material for v4.10.Rafael J. Wysocki2016-12-012-66/+110
| | |\
| | | * sched/idle: Add support for tasks that inject idlePeter Zijlstra2016-11-292-61/+102
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Idle injection drivers such as Intel powerclamp and ACPI PAD drivers use realtime tasks to take control of CPU then inject idle. There are two issues with this approach: 1. Low efficiency: injected idle task is treated as busy so sched ticks do not stop during injected idle period, the result of these unwanted wakeups can be ~20% loss in power savings. 2. Idle accounting: injected idle time is presented to user as busy. This patch addresses the issues by introducing a new PF_IDLE flag which allows any given task to be treated as idle task while the flag is set. Therefore, idle injection tasks can run through the normal flow of NOHZ idle enter/exit to get the correct accounting as well as tick stop when possible. The implication is that idle task is then no longer limited to PID == 0. Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| | | * cpuidle: Allow enforcing deepest idle state selectionJacob Pan2016-11-291-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When idle injection is used to cap power, we need to override the governor's choice of idle states. For this reason, make it possible the deepest idle state selection to be enforced by setting a flag on a given CPU to achieve the maximum potential power draw reduction. Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| * | | Merge branch 'pm-cpufreq'Rafael J. Wysocki2016-12-121-20/+99
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * pm-cpufreq: (51 commits) Documentation: intel_pstate: Document HWP energy/performance hints cpufreq: intel_pstate: Support for energy performance hints with HWP cpufreq: intel_pstate: Add locking around HWP requests cpufreq: ondemand: Set MIN_FREQUENCY_UP_THRESHOLD to 1 cpufreq: intel_pstate: Add Knights Mill CPUID MAINTAINERS: Add bug tracking system location entry for cpufreq cpufreq: dt: Add support for zx296718 cpufreq: acpi-cpufreq: drop rdmsr_on_cpus() usage cpufreq: acpi-cpufreq: Convert to hotplug state machine cpufreq: intel_pstate: fix intel_pstate_exit_perf_limits() prototype cpufreq: intel_pstate: Set EPP/EPB to 0 in performance mode cpufreq: schedutil: Rectify comment in sugov_irq_work() function cpufreq: intel_pstate: increase precision of performance limits cpufreq: intel_pstate: round up min_perf limits cpufreq: Make cpufreq_update_policy() void ACPI / processor: Make acpi_processor_ppc_has_changed() void cpufreq: Avoid using inactive policies cpufreq: intel_pstate: Generic governors support cpufreq: intel_pstate: Request P-states control from SMM if needed cpufreq: dt: Add support for r8a7743 and r8a7745 ...
| | * | | cpufreq: schedutil: Rectify comment in sugov_irq_work() functionViresh Kumar2016-11-241-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch rectifies a comment present in sugov_irq_work() function to follow proper grammar. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| | * | | cpufreq: schedutil: irq-work and mutex are only used in slow pathViresh Kumar2016-11-161-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Execute the irq-work specific initialization/exit code only when the fast path isn't available. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| | * | | cpufreq: schedutil: move slow path from workqueue to SCHED_FIFO taskViresh Kumar2016-11-161-7/+78
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If slow path frequency changes are conducted in a SCHED_OTHER context then they may be delayed for some amount of time, including indefinitely, when real time or deadline activity is taking place. Move the slow path to a real time kernel thread. In the future the thread should be made SCHED_DEADLINE. The RT priority is arbitrarily set to 50 for now. Hackbench results on ARM Exynos, dual core A15 platform for 10 iterations: $ hackbench -s 100 -l 100 -g 10 -f 20 Before After --------------------------------- 1.808 1.603 1.847 1.251 2.229 1.590 1.952 1.600 1.947 1.257 1.925 1.627 2.694 1.620 1.258 1.621 1.919 1.632 1.250 1.240 Average: 1.8829 1.5041 Based on initial work by Steve Muckle. Signed-off-by: Steve Muckle <smuckle.linux@gmail.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| | * | | cpufreq: schedutil: enable fast switch earlierViresh Kumar2016-11-161-6/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fast_switch_enabled flag will be used by both sugov_policy_alloc() and sugov_policy_free() with a later patch. Prepare for that by moving the calls to enable and disable it to the beginning of sugov_init() and end of sugov_exit(). Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| | * | | cpufreq: schedutil: Avoid indented labelsViresh Kumar2016-11-161-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Switch to the more common practice of writing labels. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | | | | Merge branch 'sched-core-for-linus' of ↵Linus Torvalds2016-12-126-248/+592
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main scheduler changes in this cycle were: - support Intel Turbo Boost Max Technology 3.0 (TBM3) by introducig a notion of 'better cores', which the scheduler will prefer to schedule single threaded workloads on. (Tim Chen, Srinivas Pandruvada) - enhance the handling of asymmetric capacity CPUs further (Morten Rasmussen) - improve/fix load handling when moving tasks between task groups (Vincent Guittot) - simplify and clean up the cputime code (Stanislaw Gruszka) - improve mass fork()ed task spread a.k.a. hackbench speedup (Vincent Guittot) - make struct kthread kmalloc()ed and related fixes (Oleg Nesterov) - add uaccess atomicity debugging (when using access_ok() in the wrong context), under CONFIG_DEBUG_ATOMIC_SLEEP=y (Peter Zijlstra) - implement various fixes, cleanups and other enhancements (Daniel Bristot de Oliveira, Martin Schwidefsky, Rafael J. Wysocki)" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits) sched/core: Use load_avg for selecting idlest group sched/core: Fix find_idlest_group() for fork kthread: Don't abuse kthread_create_on_cpu() in __kthread_create_worker() kthread: Don't use to_live_kthread() in kthread_[un]park() kthread: Don't use to_live_kthread() in kthread_stop() Revert "kthread: Pin the stack via try_get_task_stack()/put_task_stack() in to_live_kthread() function" kthread: Make struct kthread kmalloc'ed x86/uaccess, sched/preempt: Verify access_ok() context sched/x86: Make CONFIG_SCHED_MC_PRIO=y easier to enable sched/x86: Change CONFIG_SCHED_ITMT to CONFIG_SCHED_MC_PRIO x86/sched: Use #include <linux/mutex.h> instead of #include <asm/mutex.h> cpufreq/intel_pstate: Use CPPC to get max performance acpi/bus: Set _OSC for diverse core support acpi/bus: Enable HWP CPPC objects x86/sched: Add SD_ASYM_PACKING flags to x86 ITMT CPU x86/sysctl: Add sysctl for ITMT scheduling feature x86: Enable Intel Turbo Boost Max Technology 3.0 x86/topology: Define x86's arch_update_cpu_topology sched: Extend scheduler's asym packing sched/fair: Clean up the tunable parameter definitions ...
| * | | | | sched/core: Use load_avg for selecting idlest groupVincent Guittot2016-12-111-11/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | find_idlest_group() only compares the runnable_load_avg when looking for the least loaded group. But on fork intensive use case like hackbench where tasks blocked quickly after the fork, this can lead to selecting the same CPU instead of other CPUs, which have similar runnable load but a lower load_avg. When the runnable_load_avg of 2 CPUs are close, we now take into account the amount of blocked load as a 2nd selection factor. There is now 3 zones for the runnable_load of the rq: - [0 .. (runnable_load - imbalance)]: Select the new rq which has significantly less runnable_load - [(runnable_load - imbalance) .. (runnable_load + imbalance)]: The runnable loads are close so we use load_avg to chose between the 2 rq - [(runnable_load + imbalance) .. ULONG_MAX]: Keep the current rq which has significantly less runnable_load The scale factor that is currently used for comparing runnable_load, doesn't work well with small value. As an example, the use of a scaling factor fails as soon as this_runnable_load == 0 because we always select local rq even if min_runnable_load is only 1, which doesn't really make sense because they are just the same. So instead of scaling factor, we use an absolute margin for runnable_load to detect CPUs with similar runnable_load and we keep using scaling factor for blocked load. For use case like hackbench, this enable the scheduler to select different CPUs during the fork sequence and to spread tasks across the system. Tests have been done on a Hikey board (ARM based octo cores) for several kernel. The result below gives min, max, avg and stdev values of 18 runs with each configuration. The patches depend on the "no missing update_rq_clock()" work. hackbench -P -g 1 ea86cb4b7621 7dc603c9028e v4.8 v4.8+patches min 0.049 0.050 0.051 0,048 avg 0.057 0.057(0%) 0.057(0%) 0,055(+5%) max 0.066 0.068 0.070 0,063 stdev +/-9% +/-9% +/-8% +/-9% More performance numbers here: https://lkml.kernel.org/r/20161203214707.GI20785@codeblueprint.co.uk Tested-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dietmar.eggemann@arm.com Cc: kernellwp@gmail.com Cc: umgwanakikbuti@gmail.com Cc: yuyang.du@intel.comc Link: http://lkml.kernel.org/r/1481216215-24651-3-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/core: Fix find_idlest_group() for forkVincent Guittot2016-12-111-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During fork, the utilization of a task is init once the rq has been selected because the current utilization level of the rq is used to set the utilization of the fork task. As the task's utilization is still 0 at this step of the fork sequence, it doesn't make sense to look for some spare capacity that can fit the task's utilization. Furthermore, I can see perf regressions for the test: hackbench -P -g 1 because the least loaded policy is always bypassed and tasks are not spread during fork. With this patch and the fix below, we are back to same performances as for v4.8. The fix below is only a temporary one used for the test until a smarter solution is found because we can't simply remove the test which is useful for others benchmarks | @@ -5708,13 +5708,6 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, int t | | avg_cost = this_sd->avg_scan_cost; | | - /* | - * Due to large variance we need a large fuzz factor; hackbench in | - * particularly is sensitive here. | - */ | - if ((avg_idle / 512) < avg_cost) | - return -1; | - | time = local_clock(); | | for_each_cpu_wrap(cpu, sched_domain_span(sd), target, wrap) { Tested-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Morten Rasmussen <morten.rasmussen@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dietmar.eggemann@arm.com Cc: kernellwp@gmail.com Cc: umgwanakikbuti@gmail.com Cc: yuyang.du@intel.comc Link: http://lkml.kernel.org/r/1481216215-24651-2-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | Merge branch 'linus' into sched/core, to pick up fixesIngo Molnar2016-12-111-1/+3
| |\| | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched: Extend scheduler's asym packingTim Chen2016-11-243-17/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We generalize the scheduler's asym packing to provide an ordering of the cpu beyond just the cpu number. This allows the use of the ASYM_PACKING scheduler machinery to move loads to preferred CPU in a sched domain. The preference is defined with the cpu priority given by arch_asym_cpu_priority(cpu). We also record the most preferred cpu in a sched group when we build the cpu's capacity for fast lookup of preferred cpu during load balancing. Co-developed-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: linux-pm@vger.kernel.org Cc: jolsa@redhat.com Cc: rjw@rjwysocki.net Cc: linux-acpi@vger.kernel.org Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: bp@suse.de Link: http://lkml.kernel.org/r/0e73ae12737dfaafa46c07066cc7c5d3f1675e46.1479844244.git.tim.c.chen@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | sched/fair: Clean up the tunable parameter definitionsIngo Molnar2016-11-231-22/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No change in functionality: - align the default values vertically to make them easier to scan - standardize the 'default:' lines - fix minor whitespace typos Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/dl: Fix comment in pick_next_task_dl()T.Zhou2016-11-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix cut & paste oversight: s/pull_rt_task/pull_dl_task Signed-off-by: T.Zhou <t1zhou@163.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: juri.lelli@gmail.com Link: http://lkml.kernel.org/r/20161123004832.GA2983@geo Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | Merge branch 'linus' into sched/core, to pick up fixesIngo Molnar2016-11-231-8/+28
| |\ \ \ \ \ | | | |_|/ / | | |/| | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/fair: Fix task group initializationVincent Guittot2016-11-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The moves of tasks are now propagated down to root and the utilization of cfs_rq reflects reality so it doesn't need to be estimated at init. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bsegall@google.com Cc: kernellwp@gmail.com Cc: pjt@google.com Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1478598827-32372-7-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/fair: Propagate asynchrous detachVincent Guittot2016-11-161-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A task can be asynchronously detached from cfs_rq when migrating between CPUs. The load of the migrated task is then removed from source cfs_rq during its next update. We use this event to set propagation flag. During the load balance, we take advantage of the update of blocked load to propagate any pending changes. The propagation relies on patch: "sched: Fix hierarchical order in rq->leaf_cfs_rq_list" ... which orders children and parents, to ensure that it's done in one pass. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bsegall@google.com Cc: kernellwp@gmail.com Cc: pjt@google.com Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1478598827-32372-6-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/fair: Propagate load during synchronous attach/detachVincent Guittot2016-11-162-1/+188
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a task moves from/to a cfs_rq, we set a flag which is then used to propagate the change at parent level (sched_entity and cfs_rq) during next update. If the cfs_rq is throttled, the flag will stay pending until the cfs_rq is unthrottled. For propagating the utilization, we copy the utilization of group cfs_rq to the sched_entity. For propagating the load, we have to take into account the load of the whole task group in order to evaluate the load of the sched_entity. Similarly to what was done before the rewrite of PELT, we add a correction factor in case the task group's load is greater than its share so it will contribute the same load of a task of equal weight. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bsegall@google.com Cc: kernellwp@gmail.com Cc: pjt@google.com Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1478598827-32372-5-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/fair: Factorize PELT updateVincent Guittot2016-11-161-51/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Every time we modify load/utilization of sched_entity, we start to sync it with its cfs_rq. This update is done in different ways: - when attaching/detaching a sched_entity, we update cfs_rq and then we sync the entity with the cfs_rq. - when enqueueing/dequeuing the sched_entity, we update both sched_entity and cfs_rq metrics to now. Use update_load_avg() everytime we have to update and sync cfs_rq and sched_entity before changing the state of a sched_enity. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bsegall@google.com Cc: kernellwp@gmail.com Cc: pjt@google.com Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1478598827-32372-4-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/fair: Fix hierarchical order in rq->leaf_cfs_rq_listVincent Guittot2016-11-163-7/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the insertion of cfs_rq in rq->leaf_cfs_rq_list to ensure that a child will always be called before its parent. The hierarchical order in shares update list has been introduced by commit: 67e86250f8ea ("sched: Introduce hierarchal order on shares update list") With the current implementation a child can be still put after its parent. Lets take the example of: root \ b /\ c d* | e* with root -> b -> c already enqueued but not d -> e so the leaf_cfs_rq_list looks like: head -> c -> b -> root -> tail The branch d -> e will be added the first time that they are enqueued, starting with e then d. When e is added, its parents is not already on the list so e is put at the tail : head -> c -> b -> root -> e -> tail Then, d is added at the head because its parent is already on the list: head -> d -> c -> b -> root -> e -> tail e is not placed at the right position and will be called the last whereas it should be called at the beginning. Because it follows the bottom-up enqueue sequence, we are sure that we will finished to add either a cfs_rq without parent or a cfs_rq with a parent that is already on the list. We can use this event to detect when we have finished to add a new branch. For the others, whose parents are not already added, we have to ensure that they will be added after their children that have just been inserted the steps before, and after any potential parents that are already in the list. The easiest way is to put the cfs_rq just after the last inserted one and to keep track of it untl the branch is fully added. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bsegall@google.com Cc: kernellwp@gmail.com Cc: pjt@google.com Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1478598827-32372-3-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/fair: Factorize attach/detach entityVincent Guittot2016-11-161-22/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Factorize post_init_entity_util_avg() and part of attach_task_cfs_rq() in one function attach_entity_cfs_rq(). Create symmetric detach_entity_cfs_rq() function. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bsegall@google.com Cc: kernellwp@gmail.com Cc: pjt@google.com Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1478598827-32372-2-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/fair: Fix incorrect comment for capacity_marginMorten Rasmussen2016-11-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The comment for capacity_margin introduced in: 3273163c6775 ("sched/fair: Let asymmetric CPU configurations balance at wake-up") ... got its usage the wrong way round - fix it. Signed-off-by: Morten Rasmussen <morten.rasmussen@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> Cc: dietmar.eggemann@arm.com Cc: freedom.tan@mediatek.com Cc: keita.kobayashi.ym@renesas.com Cc: mgalbraith@suse.de Cc: sgurrappadi@nvidia.com Cc: vincent.guittot@linaro.org Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1476452472-24740-7-git-send-email-morten.rasmussen@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/fair: Avoid pulling tasks from non-overloaded higher capacity groupsMorten Rasmussen2016-11-161-0/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For asymmetric CPU capacity systems it is counter-productive for throughput if low capacity CPUs are pulling tasks from non-overloaded CPUs with higher capacity. The assumption is that higher CPU capacity is preferred over running alone in a group with lower CPU capacity. This patch rejects higher CPU capacity groups with one or less task per CPU as potential busiest group which could otherwise lead to a series of failing load-balancing attempts leading to a force-migration. Signed-off-by: Morten Rasmussen <morten.rasmussen@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> Cc: dietmar.eggemann@arm.com Cc: freedom.tan@mediatek.com Cc: keita.kobayashi.ym@renesas.com Cc: mgalbraith@suse.de Cc: sgurrappadi@nvidia.com Cc: vincent.guittot@linaro.org Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1476452472-24740-5-git-send-email-morten.rasmussen@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/fair: Add per-CPU min capacity to sched_group_capacityMorten Rasmussen2016-11-163-7/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | struct sched_group_capacity currently represents the compute capacity sum of all CPUs in the sched_group. Unless it is divided by the group_weight to get the average capacity per CPU, it hides differences in CPU capacity for mixed capacity systems (e.g. high RT/IRQ utilization or ARM big.LITTLE). But even the average may not be sufficient if the group covers CPUs of different capacities. Instead, by extending struct sched_group_capacity to indicate min per-CPU capacity in the group a suitable group for a given task utilization can more easily be found such that CPUs with reduced capacity can be avoided for tasks with high utilization (not implemented by this patch). Signed-off-by: Morten Rasmussen <morten.rasmussen@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> Cc: dietmar.eggemann@arm.com Cc: freedom.tan@mediatek.com Cc: keita.kobayashi.ym@renesas.com Cc: mgalbraith@suse.de Cc: sgurrappadi@nvidia.com Cc: vincent.guittot@linaro.org Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1476452472-24740-4-git-send-email-morten.rasmussen@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/fair: Consider spare capacity in find_idlest_group()Morten Rasmussen2016-11-161-5/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In low-utilization scenarios comparing relative loads in find_idlest_group() doesn't always lead to the most optimum choice. Systems with groups containing different numbers of cpus and/or cpus of different compute capacity are significantly better off when considering spare capacity rather than relative load in those scenarios. In addition to existing load based search an alternative spare capacity based candidate sched_group is found and selected instead if sufficient spare capacity exists. If not, existing behaviour is preserved. Signed-off-by: Morten Rasmussen <morten.rasmussen@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> Cc: dietmar.eggemann@arm.com Cc: freedom.tan@mediatek.com Cc: keita.kobayashi.ym@renesas.com Cc: mgalbraith@suse.de Cc: sgurrappadi@nvidia.com Cc: vincent.guittot@linaro.org Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1476452472-24740-3-git-send-email-morten.rasmussen@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/fair: Compute task/cpu utilization at wake-up correctlyMorten Rasmussen2016-11-161-4/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At task wake-up load-tracking isn't updated until the task is enqueued. The task's own view of its utilization contribution may therefore not be aligned with its contribution to the cfs_rq load-tracking which may have been updated in the meantime. Basically, the task's own utilization hasn't yet accounted for the sleep decay, while the cfs_rq may have (partially). Estimating the cfs_rq utilization in case the task is migrated at wake-up as task_rq(p)->cfs.avg.util_avg - p->se.avg.util_avg is therefore incorrect as the two load-tracking signals aren't time synchronized (different last update). To solve this problem, this patch synchronizes the task utilization with its previous rq before the task utilization is used in the wake-up path. Currently the update/synchronization is done _after_ the task has been placed by select_task_rq_fair(). The synchronization is done without having to take the rq lock using the existing mechanism used in remove_entity_load_avg(). Signed-off-by: Morten Rasmussen <morten.rasmussen@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> Cc: dietmar.eggemann@arm.com Cc: freedom.tan@mediatek.com Cc: keita.kobayashi.ym@renesas.com Cc: mgalbraith@suse.de Cc: sgurrappadi@nvidia.com Cc: vincent.guittot@linaro.org Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1476452472-24740-2-git-send-email-morten.rasmussen@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/cpuacct: Avoid %lld seq_printf warningMartin Schwidefsky2016-11-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For s390 kernel builds I keep getting this warning: kernel/sched/cpuacct.c: In function 'cpuacct_stats_show': kernel/sched/cpuacct.c:298:25: warning: format '%lld' expects argument of type 'long long int', but argument 4 has type 'clock_t {aka long int}' [-Wformat=] seq_printf(sf, "%s %lld\n", Silence the warning by adding an explicit cast. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.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> Link: http://lkml.kernel.org/r/20161111142749.6545-1-schwidefsky@de.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/cputime: Simplify task_cputime()Stanislaw Gruszka2016-11-151-42/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now since fetch_task_cputime() has no other users than task_cputime(), its code could be used directly in task_cputime(). Moreover since only 2 task_cputime() calls of 17 use a NULL argument, we can add dummy variables to those calls and remove NULL checks from task_cputimes(). Also remove NULL checks from task_cputimes_scaled(). Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1479175612-14718-5-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/cputime, powerpc, s390: Make scaled cputime arch specificStanislaw Gruszka2016-11-151-46/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Only s390 and powerpc have hardware facilities allowing to measure cputimes scaled by frequency. On all other architectures utimescaled/stimescaled are equal to utime/stime (however they are accounted separately). Remove {u,s}timescaled accounting on all architectures except powerpc and s390, where those values are explicitly accounted in the proper places. Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20161031162143.GB12646@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/cputime, powerpc: Remove cputime_to_scaled()Stanislaw Gruszka2016-11-151-14/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently cputime_to_scaled() just return it's argument on all implementations, we don't need to call this function. Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Paul Mackerras <paulus@ozlabs.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1479175612-14718-3-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/deadline: Fix typo in a commentDaniel Bristot de Oliveira2016-11-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the comment: /* * The task might have changed its scheduling policy to something * different than SCHED_DEADLINE (through switched_fromd_dl()). */ s/fromd/from/ Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: Juri Lelli <juri.lelli@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luca Abeni <luca.abeni@unitn.it> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/5408b3b3f9ee197a7b7f10fb834341100a4f2c88.1478599881.git.bristot@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | Merge branch 'linus' into sched/core, to pick up fixesIngo Molnar2016-11-113-22/+19
| |\ \ \ \ \ | | | |_|/ / | | |/| | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/core: Explain sleep/wakeup in a better wayPeter Zijlstra2016-10-251-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There were a few questions wrt. how sleep-wakeup works. Try and explain it more. Requested-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>
| * | | | | sched/fair: Kill the unused 'sched_shares_window_ns' tunableMatt Fleming2016-10-201-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The last user of this tunable was removed in 2012 in commit: 82958366cfea ("sched: Replace update_shares weight distribution with per-entity computation") Delete it since its very existence confuses people. Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Paul Turner <pjt@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20161019141059.26408-1-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | | | Merge branch 'linus' into locking/core, to pick up fixesIngo Molnar2016-12-111-1/+3
|\ \ \ \ \ \ | | |_|_|/ / | |/| | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | sched/autogroup: Fix 64-bit kernel nice level adjustmentMike Galbraith2016-11-241-1/+3
| | |_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Michael Kerrisk reported: > Regarding the previous paragraph... My tests indicate > that writing *any* value to the autogroup [nice priority level] > file causes the task group to get a lower priority. Because autogroup didn't call the then meaningless scale_load()... Autogroup nice level adjustment has been broken ever since load resolution was increased for 64-bit kernels. Use scale_load() to scale group weight. Michael Kerrisk tested this patch to fix the problem: > Applied and tested against 4.9-rc6 on an Intel u7 (4 cores). > Test setup: > > Terminal window 1: running 40 CPU burner jobs > Terminal window 2: running 40 CPU burner jobs > Terminal window 1: running 1 CPU burner job > > Demonstrated that: > * Writing "0" to the autogroup file for TW1 now causes no change > to the rate at which the process on the terminal consume CPU. > * Writing -20 to the autogroup file for TW1 caused those processes > to get the lion's share of CPU while TW2 TW3 get a tiny amount. > * Writing -20 to the autogroup files for TW1 and TW3 allowed the > process on TW3 to get as much CPU as it was getting as when > the autogroup nice values for both terminals were 0. Reported-by: Michael Kerrisk <mtk.manpages@gmail.com> Tested-by: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-man <linux-man@vger.kernel.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1479897217.4306.6.camel@gmx.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | | Merge branch 'locking/urgent' into locking/core, to pick up dependent fixesIngo Molnar2016-12-021-8/+28
|\| | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | sched/autogroup: Do not use autogroup->tg in zombie threadsOleg Nesterov2016-11-221-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Exactly because for_each_thread() in autogroup_move_group() can't see it and update its ->sched_task_group before _put() and possibly free(). So the exiting task needs another sched_move_task() before exit_notify() and we need to re-introduce the PF_EXITING (or similar) check removed by the previous change for another reason. Signed-off-by: Oleg Nesterov <oleg@redhat.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: hartsjc@redhat.com Cc: vbendel@redhat.com Cc: vlovejoy@redhat.com Link: http://lkml.kernel.org/r/20161114184612.GA15968@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | sched/autogroup: Fix autogroup_move_group() to never skip sched_move_task()Oleg Nesterov2016-11-221-11/+12
| | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The PF_EXITING check in task_wants_autogroup() is no longer needed. Remove it, but see the next patch. However the comment is correct in that autogroup_move_group() must always change task_group() for every thread so the sysctl_ check is very wrong; we can race with cgroups and even sys_setsid() is not safe because a task running with task_group() == ag->tg must participate in refcounting: int main(void) { int sctl = open("/proc/sys/kernel/sched_autogroup_enabled", O_WRONLY); assert(sctl > 0); if (fork()) { wait(NULL); // destroy the child's ag/tg pause(); } assert(pwrite(sctl, "1\n", 2, 0) == 2); assert(setsid() > 0); if (fork()) pause(); kill(getppid(), SIGKILL); sleep(1); // The child has gone, the grandchild runs with kref == 1 assert(pwrite(sctl, "0\n", 2, 0) == 2); assert(setsid() > 0); // runs with the freed ag/tg for (;;) sleep(1); return 0; } crashes the kernel. It doesn't really need sleep(1), it doesn't matter if autogroup_move_group() actually frees the task_group or this happens later. Reported-by: Vern Lovejoy <vlovejoy@redhat.com> Signed-off-by: Oleg Nesterov <oleg@redhat.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: hartsjc@redhat.com Cc: vbendel@redhat.com Link: http://lkml.kernel.org/r/20161114184609.GA15965@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | Merge branch 'linus' into locking/core, to pick up fixesIngo Molnar2016-11-113-22/+19
|\| | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | sched/core: Remove pointless printout in sched_show_task()Linus Torvalds2016-11-031-9/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In sched_show_task() we print out a useless hex number, not even a symbol, and there's a big question mark whether this even makes sense anyway, I suspect we should just remove it all. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: brgerst@gmail.com Cc: jann@thejh.net Cc: keescook@chromium.org Cc: linux-api@vger.kernel.org Cc: tycho.andersen@canonical.com Link: http://lkml.kernel.org/r/CA+55aFzphURPFzAvU4z6Moy7ZmimcwPuUdYU8bj9z0J+S8X1rw@mail.gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | sched/core: Fix oops in sched_show_task()Tetsuo Handa2016-11-031-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When CONFIG_THREAD_INFO_IN_TASK=y, it is possible that an exited thread remains in the task list after its stack pointer was already set to NULL. Therefore, thread_saved_pc() and stack_not_used() in sched_show_task() will trigger NULL pointer dereference if an attempt to dump such thread's traces (e.g. SysRq-t, khungtaskd) is made. Since show_stack() in sched_show_task() calls try_get_task_stack() and sched_show_task() is called from interrupt context, calling try_get_task_stack() from sched_show_task() will be safe as well. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: brgerst@gmail.com Cc: jann@thejh.net Cc: keescook@chromium.org Cc: linux-api@vger.kernel.org Cc: tycho.andersen@canonical.com Link: http://lkml.kernel.org/r/201611021950.FEJ34368.HFFJOOMLtQOVSF@I-love.SAKURA.ne.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
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| | \ \
| *-. \ \ Merge branches 'core-urgent-for-linus', 'irq-urgent-for-linus' and ↵Linus Torvalds2016-10-281-3/+0
| |\ \ \ \ | | | |/ / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull objtool, irq and scheduler fixes from Ingo Molnar: "One more objtool fixlet for GCC6 code generation patterns, an irq DocBook fix and an unused variable warning fix in the scheduler" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: objtool: Fix rare switch jump table pattern detection * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: doc: Add missing parameter for msi_setup * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/fair: Remove unused but set variable 'rq'
| | | * | sched/fair: Remove unused but set variable 'rq'Tobias Klauser2016-10-271-3/+0
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit: 8663e24d56dc ("sched/fair: Reorder cgroup creation code") ... the variable 'rq' in alloc_fair_sched_group() is set but no longer used. Remove it to fix the following GCC warning when building with 'W=1': kernel/sched/fair.c:8842:13: warning: variable ‘rq’ set but not used [-Wunused-but-set-variable] Signed-off-by: Tobias Klauser <tklauser@distanz.ch> 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/20161026113704.8981-1-tklauser@distanz.ch Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * / / mm: remove per-zone hashtable of bitlock waitqueuesLinus Torvalds2016-10-272-10/+16
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The per-zone waitqueues exist because of a scalability issue with the page waitqueues on some NUMA machines, but it turns out that they hurt normal loads, and now with the vmalloced stacks they also end up breaking gfs2 that uses a bit_wait on a stack object: wait_on_bit(&gh->gh_iflags, HIF_WAIT, TASK_UNINTERRUPTIBLE) where 'gh' can be a reference to the local variable 'mount_gh' on the stack of fill_super(). The reason the per-zone hash table breaks for this case is that there is no "zone" for virtual allocations, and trying to look up the physical page to get at it will fail (with a BUG_ON()). It turns out that I actually complained to the mm people about the per-zone hash table for another reason just a month ago: the zone lookup also hurts the regular use of "unlock_page()" a lot, because the zone lookup ends up forcing several unnecessary cache misses and generates horrible code. As part of that earlier discussion, we had a much better solution for the NUMA scalability issue - by just making the page lock have a separate contention bit, the waitqueue doesn't even have to be looked at for the normal case. Peter Zijlstra already has a patch for that, but let's see if anybody even notices. In the meantime, let's fix the actual gfs2 breakage by simplifying the bitlock waitqueues and removing the per-zone issue. Reported-by: Andreas Gruenbacher <agruenba@redhat.com> Tested-by: Bob Peterson <rpeterso@redhat.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Steven Whitehouse <swhiteho@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* / / locking/mutex: Rework mutex::ownerPeter Zijlstra2016-10-251-1/+1
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current mutex implementation has an atomic lock word and a non-atomic owner field. This disparity leads to a number of issues with the current mutex code as it means that we can have a locked mutex without an explicit owner (because the owner field has not been set, or already cleared). This leads to a number of weird corner cases, esp. between the optimistic spinning and debug code. Where the optimistic spinning code needs the owner field updated inside the lock region, the debug code is more relaxed because the whole lock is serialized by the wait_lock. Also, the spinning code itself has a few corner cases where we need to deal with a held lock without an owner field. Furthermore, it becomes even more of a problem when trying to fix starvation cases in the current code. We end up stacking special case on special case. To solve this rework the basic mutex implementation to be a single atomic word that contains the owner and uses the low bits for extra state. This matches how PI futexes and rt_mutex already work. By having the owner an integral part of the lock state a lot of the problems dissapear and we get a better option to deal with starvation cases, direct owner handoff. Changing the basic mutex does however invalidate all the arch specific mutex code; this patch leaves that unused in-place, a later patch will remove that. Tested-by: Jason Low <jason.low2@hpe.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>