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2014-02-28Merge branch 'timers/core' into sched/idleIngo Molnar
Avoid heavy conflicts caused by WIP patches in drivers/cpuidle/cpuidle.c, by merging these into a single base. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-24smp: Rename __smp_call_function_single() to smp_call_function_single_async()Frederic Weisbecker
The name __smp_call_function_single() doesn't tell much about the properties of this function, especially when compared to smp_call_function_single(). The comments above the implementation are also misleading. The main point of this function is actually not to be able to embed the csd in an object. This is actually a requirement that result from the purpose of this function which is to raise an IPI asynchronously. As such it can be called with interrupts disabled. And this feature comes at the cost of the caller who then needs to serialize the IPIs on this csd. Lets rename the function and enhance the comments so that they reflect these properties. Suggested-by: Christoph Hellwig <hch@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@fb.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-02-24smp: Remove wait argument from __smp_call_function_single()Frederic Weisbecker
The main point of calling __smp_call_function_single() is to send an IPI in a pure asynchronous way. By embedding a csd in an object, a caller can send the IPI without waiting for a previous one to complete as is required by smp_call_function_single() for example. As such, sending this kind of IPI can be safe even when irqs are disabled. This flexibility comes at the expense of the caller who then needs to synchronize the csd lifecycle by himself and make sure that IPIs on a single csd are serialized. This is how __smp_call_function_single() works when wait = 0 and this usecase is relevant. Now there don't seem to be any usecase with wait = 1 that can't be covered by smp_call_function_single() instead, which is safer. Lets look at the two possible scenario: 1) The user calls __smp_call_function_single(wait = 1) on a csd embedded in an object. It looks like a nice and convenient pattern at the first sight because we can then retrieve the object from the IPI handler easily. But actually it is a waste of memory space in the object since the csd can be allocated from the stack by smp_call_function_single(wait = 1) and the object can be passed an the IPI argument. Besides that, embedding the csd in an object is more error prone because the caller must take care of the serialization of the IPIs for this csd. 2) The user calls __smp_call_function_single(wait = 1) on a csd that is allocated on the stack. It's ok but smp_call_function_single() can do it as well and it already takes care of the allocation on the stack. Again it's more simple and less error prone. Therefore, using the underscore prepend API version with wait = 1 is a bad pattern and a sign that the caller can do safer and more simple. There was a single user of that which has just been converted. So lets remove this option to discourage further users. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@fb.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-02-24drivers: Enable building of Kirkwood drivers for mach-mvebuAndrew Lunn
With the move of kirkwood into mach-mvebu, drivers Kconfig need tweeking to allow the kirkwood specific drivers to be built. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Mark Brown <broonie@linaro.org> Acked-by: Kishon Vijay Abraham I <kishon@ti.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Bryan Wu <cooloney@gmail.com> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Eduardo Valentin <eduardo.valentin@ti.com> Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-02-22cpuidle/powernv: Remove redundant cpuidle_idle_call()Nicolas Pitre
The core idle loop now takes care of it. We need to add the runlatch function calls to the idle routines which was earlier taken care of by the arch specific idle routine. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Reviewed-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: linux-pm@vger.kernel.org Cc: linaro-kernel@lists.linaro.org Link: http://lkml.kernel.org/n/tip-nr4mtbkkzf2oomaj85m24o7c@git.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-12cpuidle/pseries: Fix fallout caused due to cleanup in pseries cpuidle ↵Preeti U Murthy
backend driver Commit d8c6ad3184ca651 ("sched/idle, PPC: Remove redundant cpuidle_idle_call()") reintroduced ppc64_runlatch_off/on() in the pseries cpuidle backend driver. Hence the cleanup caused by the commit "c0c4301c54adde05:pseries/cpuidle: Remove redundant call to ppc64_runlatch_off() in cpu idle routines" in conjuction with the commit d8c6ad3184ca651 causes a build failure. Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/52FAFD2D.2090306@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-11sched/idle, PPC: Remove redundant cpuidle_idle_call()Nicolas Pitre
The core idle loop now takes care of it. However a few things need checking: - Invocation of cpuidle_idle_call() in pseries_lpar_idle() happened through arch_cpu_idle() and was therefore always preceded by a call to ppc64_runlatch_off(). To preserve this property now that cpuidle_idle_call() is invoked directly from core code, a call to ppc64_runlatch_off() has been added to idle_loop_prolog() in platforms/pseries/processor_idle.c. - Similarly, cpuidle_idle_call() was followed by ppc64_runlatch_off() so a call to the later has been added to idle_loop_epilog(). - And since arch_cpu_idle() always made sure to re-enable IRQs if they were not enabled, this is now done in idle_loop_epilog() as well. The above was made in order to keep the execution flow close to the original. I don't know if that was strictly necessary. Someone well aquainted with the platform details might find some room for possible optimizations. Signed-off-by: Nicolas Pitre <nico@linaro.org> Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-sh@vger.kernel.org Cc: linux-pm@vger.kernel.org Cc: Russell King <linux@arm.linux.org.uk> Cc: linaro-kernel@lists.linaro.org Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-47o4m03citrfg9y1vxic5asb@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-07cpuidle: Handle clockevents_notify(BROADCAST_ENTER) failurePreeti U Murthy
Some archs set the CPUIDLE_FLAG_TIMER_STOP flag for idle states in which the local timers stop. The cpuidle_idle_call() currently handles such idle states by calling into the broadcast framework so as to wakeup CPUs at their next wakeup event. With the hrtimer mode of broadcast, the BROADCAST_ENTER call into the broadcast frameowork can fail for archs that do not have an external clock device to handle wakeups and the CPU in question has thus to be made the stand by CPU. This patch handles such cases by failing the call into cpuidle so that the arch can take some default action. The arch will certainly not enter a similar idle state because a failed cpuidle call will also implicitly indicate that the broadcast framework has not registered this CPU to be woken up. Hence we are safe if we fail the cpuidle call. In the process move the functions that trace idle statistics just before and after the entry and exit into idle states respectively. In other scenarios where the call to cpuidle fails, we end up not tracing idle entry and exit since a decision on an idle state could not be taken. Similarly when the call to broadcast framework fails, we skip tracing idle statistics because we are in no further position to take a decision on an alternative idle state to enter into. Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: deepthi@linux.vnet.ibm.com Cc: paulmck@linux.vnet.ibm.com Cc: fweisbec@gmail.com Cc: paulus@samba.org Cc: srivatsa.bhat@linux.vnet.ibm.com Cc: svaidy@linux.vnet.ibm.com Cc: peterz@infradead.org Cc: benh@kernel.crashing.org Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/20140207080652.17187.66344.stgit@preeti.in.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-01-29powerpc/powernv/cpuidle: Back-end cpuidle driver for powernv platform.Deepthi Dharwar
Following patch ports the cpuidle framework for powernv platform and also implements a cpuidle back-end powernv idle driver calling on to power7_nap and snooze idle states. Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29powerpc/pseries/cpuidle: smt-snooze-delay cleanup.Deepthi Dharwar
smt-snooze-delay was designed to disable NAP state or delay the entry to the NAP state prior to adoption of cpuidle framework. This is per-cpu variable. With the coming of CPUIDLE framework, states can be disabled on per-cpu basis using the cpuidle/enable sysfs entry. Also, with the coming of cpuidle driver each state's target residency is per-driver unlike earlier which was per-device. Therefore, the per-cpu sysfs smt-snooze-delay which decides the target residency of the idle state on a particular cpu causes more confusion to the user as we cannot have different smt-snooze-delay (target residency) values for each cpu. In the current code, smt-snooze-delay functionality is completely broken. It makes sense to remove smt-snooze-delay from idle driver with the coming of cpuidle framework. However, sysfs files are retained as ppc64_util currently utilises it. Once we fix ppc64_util, propose to clean up the kernel code. Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29powerpc/pseries/cpuidle: Remove MAX_IDLE_STATE macro.Deepthi Dharwar
This patch removes the usage of MAX_IDLE_STATE macro and dead code around it. The number of states are determined at run time based on the cpuidle state table selected on a given platform Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29powerpc/pseries/cpuidle: Make cpuidle-pseries backend driver a non-module.Deepthi Dharwar
Currently cpuidle-pseries backend driver cannot be built as a module due to dependencies wrt cpuidle framework. This patch removes all the module related code in the driver. Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29powerpc/pseries/cpuidle: Use cpuidle_register() for initialisation.Deepthi Dharwar
This patch replaces the cpuidle driver and devices initialisation calls with a single generic cpuidle_register() call and also includes minor refactoring of the code around it. Remove the cpu online check in snooze loop, as this code can only locally run on a cpu only if it is online. Therefore, this check is not required. Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29powerpc/pseries/cpuidle: Move processor_idle.c to drivers/cpuidle.Deepthi Dharwar
Move the file from arch specific pseries/processor_idle.c to drivers/cpuidle/cpuidle-pseries.c Make the relevant Makefile and Kconfig changes. Also, introduce Kconfig.powerpc in drivers/cpuidle for all powerpc cpuidle drivers. Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30ARM/cpuidle: remove __init tag from Calxeda cpuidle probe functionAndre Przywara
Commit 60a66e370007e8535b7a561353b07b37deaf35ba changed the Calxeda cpuidle driver to a platform driver, copying the __init tag from the _init() to the newly used _probe() function. However, "probe should not be __init." (Rob said ;-) Remove the __init tag to fix a section mismatch in the Calxeda cpuidle driver. Signed-off-by: Andre Przywara <andre.przywara@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
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>