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2013-12-03cpuidle: Check for dev before deregistering it.Konrad Rzeszutek Wilk
If not, we could end up in the unfortunate situation where we dereference a NULL pointer b/c we have cpuidle disabled. This is the case when booting under Xen (which uses the ACPI P/C states but disables the CPU idle driver) - and can be easily reproduced when booting with cpuidle.off=1. BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8156db4a>] cpuidle_unregister_device+0x2a/0x90 .. snip.. Call Trace: [<ffffffff813b15b4>] acpi_processor_power_exit+0x3c/0x5c [<ffffffff813af0a9>] acpi_processor_stop+0x61/0xb6 [<ffffffff814215bf>] __device_release_driver+0fffff81421653>] device_release_driver+0x23/0x30 [<ffffffff81420ed8>] bus_remove_device+0x108/0x180 [<ffffffff8141d9d9>] device_del+0x129/0x1c0 [<ffffffff813cb4b0>] ? unregister_xenbus_watch+0x1f0/0x1f0 [<ffffffff8141da8e>] device_unregister+0x1e/0x60 [<ffffffff814243e9>] unregister_cpu+0x39/0x60 [<ffffffff81019e03>] arch_unregister_cpu+0x23/0x30 [<ffffffff813c3c51>] handle_vcpu_hotplug_event+0xc1/0xe0 [<ffffffff813cb4f5>] xenwatch_thread+0x45/0x120 [<ffffffff810af010>] ? abort_exclusive_wait+0xb0/0xb0 [<ffffffff8108ec42>] kthread+0xd2/0xf0 [<ffffffff8108eb70>] ? kthread_create_on_node+0x180/0x180 [<ffffffff816ce17c>] ret_from_fork+0x7c/0xb0 [<ffffffff8108eb70>] ? kthread_create_on_node+0x180/0x180 This problem also appears in 3.12 and could be a candidate for backport. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: All applicable <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-14Merge tag 'pm+acpi-3.13-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael J Wysocki: - New power capping framework and the the Intel Running Average Power Limit (RAPL) driver using it from Srinivas Pandruvada and Jacob Pan. - Addition of the in-kernel switching feature to the arm_big_little cpufreq driver from Viresh Kumar and Nicolas Pitre. - cpufreq support for iMac G5 from Aaro Koskinen. - Baytrail processors support for intel_pstate from Dirk Brandewie. - cpufreq support for Midway/ECX-2000 from Mark Langsdorf. - ARM vexpress/TC2 cpufreq support from Sudeep KarkadaNagesha. - ACPI power management support for the I2C and SPI bus types from Mika Westerberg and Lv Zheng. - cpufreq core fixes and cleanups from Viresh Kumar, Srivatsa S Bhat, Stratos Karafotis, Xiaoguang Chen, Lan Tianyu. - cpufreq drivers updates (mostly fixes and cleanups) from Viresh Kumar, Aaro Koskinen, Jungseok Lee, Sudeep KarkadaNagesha, Lukasz Majewski, Manish Badarkhe, Hans-Christian Egtvedt, Evgeny Kapaev. - intel_pstate updates from Dirk Brandewie and Adrian Huang. - ACPICA update to version 20130927 includig fixes and cleanups and some reduction of divergences between the ACPICA code in the kernel and ACPICA upstream in order to improve the automatic ACPICA patch generation process. From Bob Moore, Lv Zheng, Tomasz Nowicki, Naresh Bhat, Bjorn Helgaas, David E Box. - ACPI IPMI driver fixes and cleanups from Lv Zheng. - ACPI hotplug fixes and cleanups from Bjorn Helgaas, Toshi Kani, Zhang Yanfei, Rafael J Wysocki. - Conversion of the ACPI AC driver to the platform bus type and multiple driver fixes and cleanups related to ACPI from Zhang Rui. - ACPI processor driver fixes and cleanups from Hanjun Guo, Jiang Liu, Bartlomiej Zolnierkiewicz, Mathieu Rhéaume, Rafael J Wysocki. - Fixes and cleanups and new blacklist entries related to the ACPI video support from Aaron Lu, Felipe Contreras, Lennart Poettering, Kirill Tkhai. - cpuidle core cleanups from Viresh Kumar and Lorenzo Pieralisi. - cpuidle drivers fixes and cleanups from Daniel Lezcano, Jingoo Han, Bartlomiej Zolnierkiewicz, Prarit Bhargava. - devfreq updates from Sachin Kamat, Dan Carpenter, Manish Badarkhe. - Operation Performance Points (OPP) core updates from Nishanth Menon. - Runtime power management core fix from Rafael J Wysocki and update from Ulf Hansson. - Hibernation fixes from Aaron Lu and Rafael J Wysocki. - Device suspend/resume lockup detection mechanism from Benoit Goby. - Removal of unused proc directories created for various ACPI drivers from Lan Tianyu. - ACPI LPSS driver fix and new device IDs for the ACPI platform scan handler from Heikki Krogerus and Jarkko Nikula. - New ACPI _OSI blacklist entry for Toshiba NB100 from Levente Kurusa. - Assorted fixes and cleanups related to ACPI from Andy Shevchenko, Al Stone, Bartlomiej Zolnierkiewicz, Colin Ian King, Dan Carpenter, Felipe Contreras, Jianguo Wu, Lan Tianyu, Yinghai Lu, Mathias Krause, Liu Chuansheng. - Assorted PM fixes and cleanups from Andy Shevchenko, Thierry Reding, Jean-Christophe Plagniol-Villard. * tag 'pm+acpi-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (386 commits) cpufreq: conservative: fix requested_freq reduction issue ACPI / hotplug: Consolidate deferred execution of ACPI hotplug routines PM / runtime: Use pm_runtime_put_sync() in __device_release_driver() ACPI / event: remove unneeded NULL pointer check Revert "ACPI / video: Ignore BIOS initial backlight value for HP 250 G1" ACPI / video: Quirk initial backlight level 0 ACPI / video: Fix initial level validity test intel_pstate: skip the driver if ACPI has power mgmt option PM / hibernate: Avoid overflow in hibernate_preallocate_memory() ACPI / hotplug: Do not execute "insert in progress" _OST ACPI / hotplug: Carry out PCI root eject directly ACPI / hotplug: Merge device hot-removal routines ACPI / hotplug: Make acpi_bus_hot_remove_device() internal ACPI / hotplug: Simplify device ejection routines ACPI / hotplug: Fix handle_root_bridge_removal() ACPI / hotplug: Refuse to hot-remove all objects with disabled hotplug ACPI / scan: Start matching drivers after trying scan handlers ACPI: Remove acpi_pci_slot_init() headers from internal.h ACPI / blacklist: fix name of ThinkPad Edge E530 PowerCap: Fix build error with option -Werror=format-security ... Conflicts: arch/arm/mach-omap2/opp.c drivers/Kconfig drivers/spi/spi.c
2013-10-30cpuidle: remove cpuidle_unregister_governor()Viresh Kumar
cpuidle_unregister_governor() and cpuidle_replace_governor() aren't used anymore and can be removed. They were used by cpufreq governors earlier, but since the governors can't be compiled as modules any more, these two functions aren't necessary. Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30cpuidle: don't call poll_idle_init() for every cpuViresh Kumar
poll_idle_init() just initializes drv->states[0] and so that is required to be done only once for each driver. Currently, it is called from cpuidle_enable_device() which is called for every CPU that the driver supports. That is not required, so move it to a better place and call it from __cpuidle_register_driver() so that the initialization is carried out only once. Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30cpuidle: use drv instead of cpuidle_driver in show_current_driver()Viresh Kumar
Instances of "struct cpuidle_driver *" are consistently named as "drv" in the cpuidle core except in show_current_driver(). Make that function use variable naming consistent with the rest of the code. [rjw: Changelog] Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30cpuidle: call cpuidle_get_driver() from after taking cpuidle_driver_lockViresh Kumar
There are a few cpuidle_get_driver() calls that aren't made under cpuidle_driver_lock which is incorrect. Fix them by calling cpuidle_get_driver() after taking cpuidle_driver_lock. Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30cpuidle: replace multiline statements with single line in cpuidle_idle_call()Viresh Kumar
Few statements in cpuidle_idle_call() are broken into multiple lines, although that isn't really necessary. Convert those to single line. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30cpuidle: reduce code duplication inside cpuidle_idle_call()Viresh Kumar
We are doing this twice in cpuidle_idle_call() routine: drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP Would be better if we actually store this in a local variable and use that. That reduces code duplication and likely makes this piece of code run faster (in case the compiler wasn't able to optimize it earlier) [rjw: Cast the result of bitwise AND to bool explicitly using !!] Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30cpuidle: merge two if() statements for checking error casesViresh Kumar
Two checks cpuidle_idle_call() cause the same error code to be returned if they fail, so merge them for clarity. [rjw: Changelog] Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30cpuidle: rearrange __cpuidle_register_device() to keep minimal exit pointsViresh Kumar
This patch rearranges __cpuidle_register_device() a bit in order to reduce the number of exit points in that function. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30cpuidle: rearrange code in __cpuidle_driver_init()Viresh Kumar
This is trivial patch that just reorders a few statements in __cpuidle_driver_init() routine so that we don't need both 'continue' and 'break' in the for loop. Functionally it shouldn't change anything. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30cpuidle: make __cpuidle_driver_init() return voidViresh Kumar
The only value returned by __cpuidle_driver_init() is 0, so it very well may be a void function. [rjw: Changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30cpuidle: make __cpuidle_device_init() return voidViresh Kumar
The only value returned by __cpuidle_device_init() is 0, so it very well may be a void function. Make that happen. [rjw: Changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30cpuidle: Fix comments in cpuidle coreViresh Kumar
Some comments in cpuidle core files contain trivial mistakes. This patch fixes them. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-16ARM: at91: cpuidle: Move driver to drivers/cpuidleDaniel Lezcano
As the cpuidle driver code has no more the dependency with the pm code, the 'standby' callback being passed as a parameter to the device's platform data, we can move the cpuidle driver in the drivers/cpuidle directory. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Conflicts: drivers/cpuidle/Kconfig.arm drivers/cpuidle/Makefile
2013-10-07ARM: ux500: cpuidle: fix section mismatchDaniel Lezcano
The dbx500_cpuidle_probe is tagged as an __init section but the variable dbx500_cpuidle_plat_driver is not. The dbx500_cpuidle_probe could not be declared as __init because of macro module_platform_driver builds the exit function, tags as __exit and this one refers to the dbx500_cpuidle_plat_driver which is an __initdata. That leads to a section mismatch. Fix it by removing the __init tag for the probe function. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Linus Walleij <linus.walleij@linaro.org>
2013-10-07ARM: zynq: cpuidle: convert to platform driverDaniel Lezcano
As the ux500 and the kirkwood driver, make the zynq driver a platform driver Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Michal Simek <michal.simek@xilinx.com> Tested-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
2013-10-07ARM: zynq: cpuidle: Remove useless compatibility stringDaniel Lezcano
All zynq platforms have this compatibility string and there is no any other clone. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Michal Simek <michal.simek@xilinx.com>
2013-10-07drivers: cpuidle: rename ARM big.LITTLE driver config and makefile entriesLorenzo Pieralisi
Following the reorganization of CPU idle drivers configurations into an ARM specific Kconfig, the existing idle drivers Kconfig entries were renamed and moved to the Kconfig.arm file. Makefile entries were updated accordingly. This patch renames the entries in Kconfig.arm and makefile to make the newly added big.LITTLE CPUidle driver compliant with the new naming convention. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-10-01cpuidle: calxeda: add support to use PSCI callsRob Herring
This updates the Calxeda cpuidle driver to use PSCI calls to powergate cores. This also enables cpuidle for the ECX-2000. This could possibly become a generic PSCI driver, but there are no other PSCI users in the kernel other than mach-virt. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: linux-pm@vger.kernel.org
2013-10-01ARM: highbank: cpuidle: convert to platform driverDaniel Lezcano
As the ux500 and the kirkwood driver, make the calxeda driver a platform driver [Compiled only] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-10-01cpuidle: calxeda: add cpu_pm_enter/exit callsRob Herring
Wnen powergating the core, we need to call cpu pm notifiers to save VFP state (!SMP only) and resetting the breakpoint h/w. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: linux-pm@vger.kernel.org
2013-09-12Merge tag 'pm+acpi-fixes-3.12-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management fixes from Rafael Wysocki: "All of these commits are fixes that have emerged recently and some of them fix bugs introduced during this merge window. Specifics: 1) ACPI-based PCI hotplug (ACPIPHP) fixes related to spurious events After the recent ACPIPHP changes we've seen some interesting breakage on a system that triggers device check notifications during boot for non-existing devices. Although those notifications are really spurious, we should be able to deal with them nevertheless and that shouldn't introduce too much overhead. Four commits to make that work properly. 2) Memory hotplug and hibernation mutual exclusion rework This was maent to be a cleanup, but it happens to fix a classical ABBA deadlock between system suspend/hibernation and ACPI memory hotplug which is possible if they are started roughly at the same time. Three commits rework memory hotplug so that it doesn't acquire pm_mutex and make hibernation use device_hotplug_lock which prevents it from racing with memory hotplug. 3) ACPI Intel LPSS (Low-Power Subsystem) driver crash fix The ACPI LPSS driver crashes during boot on Apple Macbook Air with Haswell that has slightly unusual BIOS configuration in which one of the LPSS device's _CRS method doesn't return all of the information expected by the driver. Fix from Mika Westerberg, for stable. 4) ACPICA fix related to Store->ArgX operation AML interpreter fix for obscure breakage that causes AML to be executed incorrectly on some machines (observed in practice). From Bob Moore. 5) ACPI core fix for PCI ACPI device objects lookup There still are cases in which there is more than one ACPI device object matching a given PCI device and we don't choose the one that the BIOS expects us to choose, so this makes the lookup take more criteria into account in those cases. 6) Fix to prevent cpuidle from crashing in some rare cases If the result of cpuidle_get_driver() is NULL, which can happen on some systems, cpuidle_driver_ref() will crash trying to use that pointer and the Daniel Fu's fix prevents that from happening. 7) cpufreq fixes related to CPU hotplug Stephen Boyd reported a number of concurrency problems with cpufreq related to CPU hotplug which are addressed by a series of fixes from Srivatsa S Bhat and Viresh Kumar. 8) cpufreq fix for time conversion in time_in_state attribute Time conversion carried out by cpufreq when user space attempts to read /sys/devices/system/cpu/cpu*/cpufreq/stats/time_in_state won't work correcty if cputime_t doesn't map directly to jiffies. Fix from Andreas Schwab. 9) Revert of a troublesome cpufreq commit Commit 7c30ed5 (cpufreq: make sure frequency transitions are serialized) was intended to address some known concurrency problems in cpufreq related to the ordering of transitions, but unfortunately it introduced several problems of its own, so I decided to revert it now and address the original problems later in a more robust way. 10) Intel Haswell CPU models for intel_pstate from Nell Hardcastle. 11) cpufreq fixes related to system suspend/resume The recent cpufreq changes that made it preserve CPU sysfs attributes over suspend/resume cycles introduced a possible NULL pointer dereference that caused it to crash during the second attempt to suspend. Three commits from Srivatsa S Bhat fix that problem and a couple of related issues. 12) cpufreq locking fix cpufreq_policy_restore() should acquire the lock for reading, but it acquires it for writing. Fix from Lan Tianyu" * tag 'pm+acpi-fixes-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (25 commits) cpufreq: Acquire the lock in cpufreq_policy_restore() for reading cpufreq: Prevent problems in update_policy_cpu() if last_cpu == new_cpu cpufreq: Restructure if/else block to avoid unintended behavior cpufreq: Fix crash in cpufreq-stats during suspend/resume intel_pstate: Add Haswell CPU models Revert "cpufreq: make sure frequency transitions are serialized" cpufreq: Use signed type for 'ret' variable, to store negative error values cpufreq: Remove temporary fix for race between CPU hotplug and sysfs-writes cpufreq: Synchronize the cpufreq store_*() routines with CPU hotplug cpufreq: Invoke __cpufreq_remove_dev_finish() after releasing cpu_hotplug.lock cpufreq: Split __cpufreq_remove_dev() into two parts cpufreq: Fix wrong time unit conversion cpufreq: serialize calls to __cpufreq_governor() cpufreq: don't allow governor limits to be changed when it is disabled ACPI / bind: Prefer device objects with _STA to those without it ACPI / hotplug / PCI: Avoid parent bus rescans on spurious device checks ACPI / hotplug / PCI: Use _OST to notify firmware about notify status ACPI / hotplug / PCI: Avoid doing too much for spurious notifies ACPICA: Fix for a Store->ArgX when ArgX contains a reference to a field. ACPI / hotplug / PCI: Don't trim devices before scanning the namespace ...
2013-09-09Merge tag 'drivers-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC driver update from Kevin Hilman: "This contains the ARM SoC related driver updates for v3.12. The only thing this cycle are core PM updates and CPUidle support for ARM's TC2 big.LITTLE development platform" * tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: cpuidle: big.LITTLE: vexpress-TC2 CPU idle driver ARM: vexpress: tc2: disable GIC CPU IF in tc2_pm_suspend drivers: irq-chip: irq-gic: introduce gic_cpu_if_down()
2013-08-30cpuidle: Check the result of cpuidle_get_driver() against NULLDaniel Fu
If the current CPU has no cpuidle driver, drv will be NULL in cpuidle_driver_ref(). Check if that is the case before trying to bump up the driver's refcount to prevent the kernel from crashing. [rjw: Subject and changelog] Signed-off-by: Daniel Fu <danifu@nvidia.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-29cpuidle: coupled: fix race condition between pokes and safe stateColin Cross
The coupled cpuidle waiting loop clears pending pokes before entering the safe state. If a poke arrives just before the pokes are cleared, but after the while loop condition checks, the poke will be lost and the cpu will stay in the safe state until another interrupt arrives. This may cause the cpu that sent the poke to spin in the ready loop with interrupts off until another cpu receives an interrupt, and if no other cpus have interrupts routed to them it can spin forever. Change the return value of cpuidle_coupled_clear_pokes to return if a poke was cleared, and move the need_resched() checks into the callers. In the waiting loop, if a poke was cleared restart the loop to repeat the while condition checks. Reported-by: Neil Zhang <zhangwm@marvell.com> Signed-off-by: Colin Cross <ccross@android.com> Cc: 3.6+ <stable@vger.kernel.org> # 3.6+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-29cpuidle: coupled: abort idle if pokes are pendingColin Cross
Joseph Lo <josephl@nvidia.com> reported a lockup on Tegra20 caused by a race condition in coupled cpuidle. When two or more cpus enter idle at the same time, the first cpus to arrive may go to the ready loop without processing pending pokes from the last cpu to arrive. This patch adds a check for pending pokes once all cpus have been synchronized in the ready loop and resets the coupled state and retries if any cpus failed to handle their pending poke. Retrying on all cpus may trigger the same issue again, so this patch also adds a check to ensure that each cpu has received at least one poke between when it enters the waiting loop and when it moves on to the ready loop. Reported-and-tested-by: Joseph Lo <josephl@nvidia.com> Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Colin Cross <ccross@android.com> Cc: 3.6+ <stable@vger.kernel.org> # 3.6+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-29cpuidle: coupled: disable interrupts after entering safe stateColin Cross
Calling cpuidle_enter_state is expected to return with interrupts enabled, but interrupts must be disabled before starting the ready loop synchronization stage. Call local_irq_disable after each call to cpuidle_enter_state for the safe state. Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Colin Cross <ccross@android.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-28Merge branch 'cpuidle/biglittle' into next/driversOlof Johansson
From Lorenzo Pieralisi: This patch series contains: - GIC driver update to add a method to disable the GIC CPU IF - TC2 MCPM update to add GIC CPU disabling to suspend method - TC2 CPU idle big.LITTLE driver * cpuidle/biglittle: cpuidle: big.LITTLE: vexpress-TC2 CPU idle driver ARM: vexpress: tc2: disable GIC CPU IF in tc2_pm_suspend drivers: irq-chip: irq-gic: introduce gic_cpu_if_down() ARM: vexpress/TC2: implement PM suspend method ARM: vexpress/TC2: basic PM support ARM: vexpress: Add SCC to V2P-CA15_A7's device tree ARM: vexpress/TC2: add Serial Power Controller (SPC) support ARM: vexpress/dcscb: fix cache disabling sequences Signed-off-by: Olof Johansson <olof@lixom.net>
2013-08-28cpuidle: big.LITTLE: vexpress-TC2 CPU idle driverLorenzo Pieralisi
The big.LITTLE architecture is composed of two clusters of cpus. One cluster contains less powerful but more energy efficient processors and the other cluster groups the powerful but energy-intensive cpus. The TC2 testchip implements two clusters of CPUs (A7 and A15 clusters in a big.LITTLE configuration) connected through a CCI interconnect that manages coherency of their respective L2 caches and intercluster distributed virtual memory messages (DVM). TC2 testchip integrates a power controller that manages cores resets, wake-up IRQs and cluster low-power states. Power states are managed at cluster level, which means that voltage is removed from a cluster iff all cores in a cluster are in a wfi state. Single cores can enter a reset state which is identical to wfi in terms of power consumption but simplifies the way cluster states are entered. This patch provides a multiple driver CPU idle implementation for TC2 which paves the way for a generic big.LITTLE idle driver for all upcoming big.LITTLE based systems on chip. The driver relies on the MCPM infrastructure to coordinate and manage core power states; in particular MCPM allows to suspend specific cores and hides the CPUs coordination required to shut-down clusters of CPUs. Power down sequences for the respective clusters are implemented in the MCPM TC2 backend, with all code needed to clean caches and exit coherency. The multiple driver CPU idle infrastructure allows to define different C-states for big and little cores, determined at boot by checking the part id of the possible CPUs and initializing the respective logical masks in the big and little drivers. Current big.little systems are composed of A7 and A15 clusters, as implemented in TC2, but in the future that may change and the driver will have evolve to retrieve what is a 'big' cpu and what is a 'little' cpu in order to build the correct topology. Cc: Kevin Hilman <khilman@linaro.org> Cc: Amit Kucheria <amit.kucheria@linaro.org> Cc: Olof Johansson <olof@lixom.net> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Olof Johansson <olof@lixom.net>
2013-08-23cpuidle: Change struct menu_device field typesTuukka Tikkanen
Field predicted_us value can never exceed expected_us value, but it has a potentially larger type. As there is no need for additional 32 bits of zeroes on 32 bit plaforms, change the type of predicted_us to match the type of expected_us. Field correction_factor is used to store a value that cannot exceed the product of RESOLUTION and DECAY (default 1024*8 = 8192). The constants cannot in practice be incremented to such values, that they'd overflow unsigned int even on 32 bit systems, so the type is changed to avoid unnecessary 64 bit arithmetic on 32 bit systems. One multiplication of (now) 32 bit values needs an added cast to avoid truncation of the result and has been added. In order to avoid another multiplication from 32 bit domain to 64 bit domain, the new correction_factor calculation has been changed from new = old * (DECAY-1) / DECAY to new = old - old / DECAY, which with infinite precision would yeild exactly the same result, but now changes the direction of rounding. The impact is not significant as the maximum accumulated difference cannot exceed the value of DECAY, which is relatively small compared to product of RESOLUTION and DECAY (8 / 8192). Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Add a comment warning about possible overflowTuukka Tikkanen
The menu governor has a number of tunable constants that may be changed in the source. If certain combination of values are chosen, an overflow is possible when the correction_factor is being recalculated. This patch adds a warning regarding this possibility and describes the change needed for fixing the issue. The change should not be permanently enabled, as it will hurt performance when it is not needed. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Fix variable domains in get_typical_interval()Tuukka Tikkanen
The menu governor uses a static function get_typical_interval() to try to detect a repeating pattern of wakeups. The previous interval durations are stored as an array of unsigned ints, but the arithmetic in the function is performed exclusively as 64 bit values, even when the value stored in a variable is known not to exceed unsigned int, which may be smaller and more efficient on some platforms. This patch changes the types of varibles used to store some intermediates, the maximum and and the cutoff threshold to unsigned ints. Average and standard deviation are still treated as 64 bit values, even when the values are known to be within the domain of unsigned int, to avoid casts to ensure correct integer promotion for arithmetic operations. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Fix menu_device->intervals typeTuukka Tikkanen
Struct menu_device member intervals is declared as u32, but the value stored is (unsigned) int. The type is changed to match the value being stored. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: CodingStyle: Break up multiple assignments on single lineTuukka Tikkanen
The function get_typical_interval() initializes a number of variables that are immediately after declarations assigned constant values. In addition, there are multiple assignments on a single line, which is explicitly forbidden by Documentation/CodingStyle. This patch removes redundant initial values for the variables and breaks up the multiple assignment line. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Check called function parameter in get_typical_interval()Tuukka Tikkanen
get_typical_interval() uses int_sqrt() in calculation of standard deviation. The formal parameter of int_sqrt() is unsigned long, which may on some platforms be smaller than the 64 bit unsigned integer used as the actual parameter. The overflow can occur frequently when actual idle period lengths are in hundreds of milliseconds. This patch adds a check for such overflow and rejects the candidate average when an overflow would occur. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Rearrange code and comments in get_typical_interval()Tuukka Tikkanen
This patch rearranges a if-return-elsif-goto-fi-return sequence into if-return-fi-if-return-fi-goto sequence. The functionality remains the same. Also, a lengthy comment that did not describe the functionality in the order it occurs is split into half and top half is moved closer to actual implementation it describes. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Ignore interval prediction result when timer is shorterTuukka Tikkanen
This patch prevents cpuidle menu governor from using repeating interval prediction result if the idle period predicted is longer than the one allowed by shortest running timer. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14cpuidle-kirkwood.c: simplify use of devm_ioremap_resource()Julia Lawall
Remove unneeded error handling on the result of a call to platform_get_resource when the value is passed to devm_ioremap_resource(). A simplified version of the semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression pdev,res,n,e,e1; expression ret != 0; identifier l; @@ - res = platform_get_resource(pdev, IORESOURCE_MEM, n); ... when != res - if (res == NULL) { ... \(goto l;\|return ret;\) } ... when != res + res = platform_get_resource(pdev, IORESOURCE_MEM, n); e = devm_ioremap_resource(e1, res); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14Merge branch 'cpuidle/arm-next' of ↵Rafael J. Wysocki
git://git.linaro.org/people/dlezcano/linux into pm-cpuidle Pull ARM cpuidle updates from Daniel Lezcano. * 'cpuidle/arm-next' of git://git.linaro.org/people/dlezcano/linux: cpuidle: kirkwood: Make kirkwood_cpuidle_remove function static cpuidle: calxeda: Add missing __iomem annotation SH: cpuidle: Add missing parameter for cpuidle_register()
2013-08-14Merge back earlier 'pm-cpuidle' material.Rafael J. Wysocki
2013-08-12cpuidle: kirkwood: Make kirkwood_cpuidle_remove function staticJingoo Han
This local symbol is used only in this file. Fix the following sparse warnings: drivers/cpuidle/cpuidle-kirkwood.c:73:5: warning: symbol 'kirkwood_cpuidle_remove' was not declared. Should it be static ? Signed-off-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Jason Cooper <jason@lakedaemon.net> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-08-12cpuidle: calxeda: Add missing __iomem annotationJingoo Han
Added missing __iomem annotation in order to fix the following sparse warnings: drivers/cpuidle/cpuidle-calxeda.c:44:24: warning: incorrect type in argument 1 (different address spaces) drivers/cpuidle/cpuidle-calxeda.c:44:24: expected void [noderef] <asn:2>*<noident> drivers/cpuidle/cpuidle-calxeda.c:44:24: got void *extern [addressable] [toplevel] scu_base_addr drivers/cpuidle/cpuidle-calxeda.c:56:24: warning: incorrect type in argument 1 (different address spaces) drivers/cpuidle/cpuidle-calxeda.c:56:24: expected void [noderef] <asn:2>*<noident> drivers/cpuidle/cpuidle-calxeda.c:56:24: got void *extern [addressable] [toplevel] scu_base_addr Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-29Revert "cpuidle: Quickly notice prediction failure for repeat mode"Rafael J. Wysocki
Revert commit 69a37bea (cpuidle: Quickly notice prediction failure for repeat mode), because it has been identified as the source of a significant performance regression in v3.8 and later as explained by Jeremy Eder: We believe we've identified a particular commit to the cpuidle code that seems to be impacting performance of variety of workloads. The simplest way to reproduce is using netperf TCP_RR test, so we're using that, on a pair of Sandy Bridge based servers. We also have data from a large database setup where performance is also measurably/positively impacted, though that test data isn't easily share-able. Included below are test results from 3 test kernels: kernel reverts ----------------------------------------------------------- 1) vanilla upstream (no reverts) 2) perfteam2 reverts e11538d1f03914eb92af5a1a378375c05ae8520c 3) test reverts 69a37beabf1f0a6705c08e879bdd5d82ff6486c4 e11538d1f03914eb92af5a1a378375c05ae8520c In summary, netperf TCP_RR numbers improve by approximately 4% after reverting 69a37beabf1f0a6705c08e879bdd5d82ff6486c4. When 69a37beabf1f0a6705c08e879bdd5d82ff6486c4 is included, C0 residency never seems to get above 40%. Taking that patch out gets C0 near 100% quite often, and performance increases. The below data are histograms representing the %c0 residency @ 1-second sample rates (using turbostat), while under netperf test. - If you look at the first 4 histograms, you can see %c0 residency almost entirely in the 30,40% bin. - The last pair, which reverts 69a37beabf1f0a6705c08e879bdd5d82ff6486c4, shows %c0 in the 80,90,100% bins. Below each kernel name are netperf TCP_RR trans/s numbers for the particular kernel that can be disclosed publicly, comparing the 3 test kernels. We ran a 4th test with the vanilla kernel where we've also set /dev/cpu_dma_latency=0 to show overall impact boosting single-threaded TCP_RR performance over 11% above baseline. 3.10-rc2 vanilla RX + c0 lock (/dev/cpu_dma_latency=0): TCP_RR trans/s 54323.78 ----------------------------------------------------------- 3.10-rc2 vanilla RX (no reverts) TCP_RR trans/s 48192.47 Receiver %c0 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 0]: 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 59]: *********************************************************** 40.0000 - 50.0000 [ 1]: * 50.0000 - 60.0000 [ 0]: 60.0000 - 70.0000 [ 0]: 70.0000 - 80.0000 [ 0]: 80.0000 - 90.0000 [ 0]: 90.0000 - 100.0000 [ 0]: Sender %c0 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 0]: 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 11]: *********** 40.0000 - 50.0000 [ 49]: ************************************************* 50.0000 - 60.0000 [ 0]: 60.0000 - 70.0000 [ 0]: 70.0000 - 80.0000 [ 0]: 80.0000 - 90.0000 [ 0]: 90.0000 - 100.0000 [ 0]: ----------------------------------------------------------- 3.10-rc2 perfteam2 RX (reverts commit e11538d1f03914eb92af5a1a378375c05ae8520c) TCP_RR trans/s 49698.69 Receiver %c0 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 1]: * 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 59]: *********************************************************** 40.0000 - 50.0000 [ 0]: 50.0000 - 60.0000 [ 0]: 60.0000 - 70.0000 [ 0]: 70.0000 - 80.0000 [ 0]: 80.0000 - 90.0000 [ 0]: 90.0000 - 100.0000 [ 0]: Sender %c0 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 0]: 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 2]: ** 40.0000 - 50.0000 [ 58]: ********************************************************** 50.0000 - 60.0000 [ 0]: 60.0000 - 70.0000 [ 0]: 70.0000 - 80.0000 [ 0]: 80.0000 - 90.0000 [ 0]: 90.0000 - 100.0000 [ 0]: ----------------------------------------------------------- 3.10-rc2 test RX (reverts 69a37beabf1f0a6705c08e879bdd5d82ff6486c4 and e11538d1f03914eb92af5a1a378375c05ae8520c) TCP_RR trans/s 47766.95 Receiver %c0 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 1]: * 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 27]: *************************** 40.0000 - 50.0000 [ 2]: ** 50.0000 - 60.0000 [ 0]: 60.0000 - 70.0000 [ 2]: ** 70.0000 - 80.0000 [ 0]: 80.0000 - 90.0000 [ 0]: 90.0000 - 100.0000 [ 28]: **************************** Sender: 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 0]: 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 11]: *********** 40.0000 - 50.0000 [ 0]: 50.0000 - 60.0000 [ 1]: * 60.0000 - 70.0000 [ 0]: 70.0000 - 80.0000 [ 3]: *** 80.0000 - 90.0000 [ 7]: ******* 90.0000 - 100.0000 [ 38]: ************************************** These results demonstrate gaining back the tendency of the CPU to stay in more responsive, performant C-states (and thus yield measurably better performance), by reverting commit 69a37beabf1f0a6705c08e879bdd5d82ff6486c4. Requested-by: Jeremy Eder <jeder@redhat.com> Tested-by: Len Brown <len.brown@intel.com> Cc: 3.8+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-29Revert "cpuidle: Quickly notice prediction failure in general case"Rafael J. Wysocki
Revert commit e11538d1 (cpuidle: Quickly notice prediction failure in general case), since it depends on commit 69a37be (cpuidle: Quickly notice prediction failure for repeat mode) that has been identified as the source of a significant performance regression in v3.8 and later. Requested-by: Jeremy Eder <jeder@redhat.com> Tested-by: Len Brown <len.brown@intel.com> Cc: 3.8+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-27Merge branch 'cpuidle-arm' into pm-cpuidleRafael J. Wysocki
* cpuidle-arm: ARM: ux500: cpuidle: Move ux500 cpuidle driver to drivers/cpuidle ARM: ux500: cpuidle: Remove pointless include ARM: ux500: cpuidle: Instantiate the driver from platform device ARM: davinci: cpuidle: Fix target residency cpuidle: Add Kconfig.arm and move calxeda, kirkwood and zynq
2013-07-27ARM: ux500: cpuidle: Move ux500 cpuidle driver to drivers/cpuidleDaniel Lezcano
There is no more dependency with arch/arm headers, so we can safely move the driver to the drivers/cpuidle directory. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Linus Walleij <linus.walleij@linaro.org>
2013-07-27cpuidle: Add Kconfig.arm and move calxeda, kirkwood and zynqSahara
Add Kconfig.arm for ARM cpuidle drivers and moves calxeda, kirkwood and zynq to Kconfig.arm. Like in the cpufreq menu, "CPU Idle" menu is added to drivers/cpuidle/Kconfig. Signed-off-by: Sahara <keun-o.park@windriver.com>
2013-07-15cpuidle: Check if device is already registeredDaniel Lezcano
Make __cpuidle_register_device() check whether or not the device has been registered already and return -EBUSY immediately if that's the case. [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15cpuidle: Introduce __cpuidle_device_init()Daniel Lezcano
Add __cpuidle_device_init() for initializing the cpuidle_device structure. [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>