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path: root/drivers/cpufreq
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2013-08-21cpufreq: cpufreq-cpu0: remove device tree parsing for cpu nodesSudeep KarkadaNagesha
Now that the cpu device registration initialises the of_node(if available) appropriately for all the cpus, parsing here is redundant. This patch removes all DT parsing and uses cpu->of_node instead. Acked-by: Shawn Guo <shawn.guo@linaro.org> Acked-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
2013-08-21cpufreq: imx6q-cpufreq: remove device tree parsing for cpu nodesSudeep KarkadaNagesha
Now that the cpu device registration initialises the of_node(if available) appropriately for all the cpus, parsing here is redundant. This patch removes all DT parsing and uses cpu->of_node instead. Acked-by: Shawn Guo <shawn.guo@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
2013-08-21cpufreq: fix bad unlock balance on !CONFIG_SMPLi Zhong
This patch tries to fix lockdep complaint attached below. It seems that we should always read acquire the cpufreq_rwsem, whether CONFIG_SMP is enabled or not. And CONFIG_HOTPLUG_CPU depends on CONFIG_SMP, so it seems we don't need CONFIG_SMP for the code enabled by CONFIG_HOTPLUG_CPU. [ 0.504191] ===================================== [ 0.504627] [ BUG: bad unlock balance detected! ] [ 0.504627] 3.11.0-rc6-next-20130819 #1 Not tainted [ 0.504627] ------------------------------------- [ 0.504627] swapper/1 is trying to release lock (cpufreq_rwsem) at: [ 0.504627] [<ffffffff813d927a>] cpufreq_add_dev+0x13a/0x3e0 [ 0.504627] but there are no more locks to release! [ 0.504627] [ 0.504627] other info that might help us debug this: [ 0.504627] 1 lock held by swapper/1: [ 0.504627] #0: (subsys mutex#4){+.+.+.}, at: [<ffffffff8134a7bf>] subsys_interface_register+0x4f/0xe0 [ 0.504627] [ 0.504627] stack backtrace: [ 0.504627] CPU: 0 PID: 1 Comm: swapper Not tainted 3.11.0-rc6-next-20130819 #1 [ 0.504627] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 [ 0.504627] ffffffff813d927a ffff88007f847c98 ffffffff814c062b ffff88007f847cc8 [ 0.504627] ffffffff81098bce ffff88007f847cf8 ffffffff81aadc30 ffffffff813d927a [ 0.504627] 00000000ffffffff ffff88007f847d68 ffffffff8109d0be 0000000000000006 [ 0.504627] Call Trace: [ 0.504627] [<ffffffff813d927a>] ? cpufreq_add_dev+0x13a/0x3e0 [ 0.504627] [<ffffffff814c062b>] dump_stack+0x19/0x1b [ 0.504627] [<ffffffff81098bce>] print_unlock_imbalance_bug+0xfe/0x110 [ 0.504627] [<ffffffff813d927a>] ? cpufreq_add_dev+0x13a/0x3e0 [ 0.504627] [<ffffffff8109d0be>] lock_release_non_nested+0x1ee/0x310 [ 0.504627] [<ffffffff81099d0e>] ? mark_held_locks+0xae/0x120 [ 0.504627] [<ffffffff811510cb>] ? kfree+0xcb/0x1d0 [ 0.504627] [<ffffffff813d77ea>] ? cpufreq_policy_free+0x4a/0x60 [ 0.504627] [<ffffffff813d927a>] ? cpufreq_add_dev+0x13a/0x3e0 [ 0.504627] [<ffffffff8109d2a4>] lock_release+0xc4/0x250 [ 0.504627] [<ffffffff8106c9f3>] up_read+0x23/0x40 [ 0.504627] [<ffffffff813d927a>] cpufreq_add_dev+0x13a/0x3e0 [ 0.504627] [<ffffffff8134a809>] subsys_interface_register+0x99/0xe0 [ 0.504627] [<ffffffff81b19f3b>] ? cpufreq_gov_dbs_init+0x12/0x12 [ 0.504627] [<ffffffff813d7f0d>] cpufreq_register_driver+0x9d/0x1d0 [ 0.504627] [<ffffffff81b19f3b>] ? cpufreq_gov_dbs_init+0x12/0x12 [ 0.504627] [<ffffffff81b1a039>] acpi_cpufreq_init+0xfe/0x1f8 [ 0.504627] [<ffffffff810002ba>] do_one_initcall+0xda/0x180 [ 0.504627] [<ffffffff81ae301e>] kernel_init_freeable+0x12c/0x1bb [ 0.504627] [<ffffffff81ae2841>] ? do_early_param+0x8c/0x8c [ 0.504627] [<ffffffff814b4dd0>] ? rest_init+0x140/0x140 [ 0.504627] [<ffffffff814b4dde>] kernel_init+0xe/0xf0 [ 0.504627] [<ffffffff814d029a>] ret_from_fork+0x7a/0xb0 [ 0.504627] [<ffffffff814b4dd0>] ? rest_init+0x140/0x140 Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Acked-and-tested-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-20cpufreq: Use cpufreq_policy_list for iterating over policiesViresh Kumar
To iterate over all policies we currently iterate over all online CPUs and then get the policy for each of them which is suboptimal. Use the newly created cpufreq_policy_list for this purpose instead. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-20cpufreq: remove cpufreq_policy_cpu per-cpu variableViresh Kumar
cpufreq_policy_cpu per-cpu variables are used for storing the ID of the CPU that manages the given CPU's policy. However, we also store a policy pointer for each cpu in cpufreq_cpu_data, so the cpufreq_policy_cpu information is simply redundant. It is better to use cpufreq_cpu_data to retrieve a policy and get policy->cpu from there, so make that happen everywhere and drop the cpufreq_policy_cpu per-cpu variables which aren't necessary any more. [rjw: Changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-20cpufreq: remove unnecessary check in __cpufreq_governor()Viresh Kumar
We don't need to check if event is CPUFREQ_GOV_POLICY_INIT and put governor module as we are sure event can only be START/STOP here. Remove the useless check. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-20cpufreq: remove policy from cpufreq_policy_list during suspendViresh Kumar
cpufreq_policy_list is a list of active policies. We do remove policies from this list when all CPUs belonging to that policy are removed. But during system suspend we don't really free a policy struct as it will be used again during resume, so we didn't remove it from cpufreq_policy_list as well.. However, this is incorrect. We are saying this policy isn't valid anymore and must not be referenced (though we haven't freed it), but it can still be used by code that iterates over cpufreq_policy_list. Remove policy from this list during system suspend as well. Of course, we must add it back whenever the first CPU belonging to that policy shows up. [rjw: Changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-20cpufreq: Fix white space in __cpufreq_remove_dev()Viresh Kumar
Align closing brace '}' of an if block. [rjw: Subject and changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-18Revert "cpufreq: Use cpufreq_policy_list for iterating over policies"Rafael J. Wysocki
Revert commit eb60852 (cpufreq: Use cpufreq_policy_list for iterating over policies), because it breaks system suspend/resume on multiple machines. It either causes resume to block indefinitely or causes the BUG_ON() in lock_policy_rwsem_##mode() to trigger on sysfs accesses to cpufreq attributes. Conflicts: drivers/cpufreq/cpufreq.c
2013-08-14cpufreq: unicore2: Staticize local symbolJingoo Han
This local symbol is used only in this file. Fix the following sparse warnings: drivers/cpufreq/unicore2-cpufreq.c:27:5: warning: symbol 'ucv2_verify_speed' was not declared. Should it be static? Signed-off-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14cpufreq / s3c24xx: Fix s3c_cpufreq_initclks() __init attribute locationHanjun Guo
__init belongs after the return type on functions, not before it. Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14cpufreq / pxa2xx: Fix pxa_cpufreq_init_voltages() __init attribute locationHanjun Guo
__init belongs after the return type on functions, not before it. Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14cpufreq / gx: Fix gx_detect_chipset() __init attribute locationHanjun Guo
__init belongs after the return type on functions, not before it. Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14pxa3xx-cpufreq.c: Avoid using ARRAY_AND_SIZE(e) as a function argumentJulia Lawall
Replace ARRAY_AND_SIZE(e) in function argument position to avoid hiding the arity of the called function. The semantic match that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression e,f; @@ f(..., - ARRAY_AND_SIZE(e) + e,ARRAY_SIZE(e) ,...) // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14cpufreq: cpufreq-cpu0: NULL is a valid regulatorMark Brown
Since NULL could in theory be a valid regulator we ought to check for IS_ERR() rather than for NULL. In practice this is unlikely to be an issue but it's better for neatness. Signed-off-by: Mark Brown <broonie@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14acpi-cpufreq: Use cpufreq_freq_attr_rw to define the cpb attributeLan Tianyu
Standardise the defintion of the cpb (Core Performance Boost) attribute in the acpi-cpufreq driver via the cpufreq_freq_attr_rw macro. [rjw: Subject and changelog] Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14Merge branch 'cpufreq-fixes' of git://git.linaro.org/people/vireshk/linux ↵Rafael J. Wysocki
into pm-cpufreq Pull ARM cpufreq fixes from Viresh Kumar. * 'cpufreq-fixes' of git://git.linaro.org/people/vireshk/linux: cpufreq: fix EXYNOS drivers selection cpufreq: exynos5440: Fix to skip when new frequency same as current
2013-08-14Merge back earlier 'pm-cpufreq' materialRafael J. Wysocki
2013-08-13cpufreq: cpufreq-cpu0: Use devm_regulator_get_optional()Mark Brown
Since the cpufreq-cpu0 driver is capable of coping without a software controllable regulator and would be confused by a dummy one it should use devm_regulator_get_optional() to ensure no dummy is provided. Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-12cpufreq: fix EXYNOS drivers selectionBartlomiej Zolnierkiewicz
* remove superfluous pr_debug() call from exynos_cpufreq_init() (init errors are always logged anyway) * add dummy per-SoC type init functions to exynos-cpufreq.h * make per-SoC type cpufreq config options selectable * make CONFIG_ARM_EXYNOS_CPUFREQ config option invisible to user and automatically enable it when needed This patch fixes following issues: * EXYNOS per-SoC type cpufreq support (i.e. exynos4210-cpufreq.c) being always built if given SoC support was enabled (i.e. CPU_EXYNOS4210), even if common EXYNOS cpufreq support was disabled * inability to select cpufreq for each SoC type separately (it could be only enabled/disabled for all SoCs for which support was enabled) * EXYNOS5440 cpufreq support was always enabled when EXYNOS5440 support was enabled and couldn't be disabled Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2013-08-12cpufreq: exynos5440: Fix to skip when new frequency same as currentAmit Daniel Kachhap
This patch fixes the issue of un-necessary setting the clock controller when the new target frequency is same as the current one. This case usually occurs with governors like ondemand which passes the target frequency as the percentage of average frequency. This check is present in most of the cpufreq drivers. Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2013-08-10cpufreq: improve error checking on return values of __cpufreq_governor()Viresh Kumar
The __cpufreq_governor() function can fail in rare cases especially if there are bugs in cpufreq drivers. Thus we must stop processing as soon as this routine fails, otherwise it may result in undefined behavior. This patch adds error checking code whenever this routine is called from any place. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-10cpufreq: Drop the owner field from struct cpufreq_driverViresh Kumar
We don't need to set .owner = THIS_MODULE any more in cpufreq drivers as this field isn't used any more by the cpufreq core. This patch removes it and updates all dependent drivers accordingly. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-10cpufreq: Use rwsem for protecting critical sectionsViresh Kumar
Critical sections of the cpufreq core are protected with the help of the driver module owner's refcount, which isn't the correct approach, because it causes rmmod to return an error when some routine has updated that refcount. Let's use rwsem for this purpose instead. Only cpufreq_unregister_driver() will use write sem and everybody else will use read sem. [rjw: Subject & changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-10cpufreq: Fix broken usage of governor->owner's refcountViresh Kumar
The cpufreq governor owner refcount usage is broken. We should only increment that refcount when a CPUFREQ_GOV_POLICY_INIT event has come and it should only be decremented if CPUFREQ_GOV_POLICY_EXIT has come. Currently, there can be situations where the governor is in use, but we have allowed it to be unloaded which may result in undefined behavior. Let's fix it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-10cpufreq: Use cpufreq_policy_list for iterating over policiesViresh Kumar
To iterate over all policies we currently iterate over all CPUs and then get the policy for each of them. Let's use the newly created cpufreq_policy_list for this purpose. [rjw: Changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-10cpufreq: Store cpufreq policies in a listLukasz Majewski
Policies available in the cpufreq framework are now linked together. They are accessible via cpufreq_policy_list defined in the cpufreq core. [rjw: Fix from Yinghai Lu folded in] Signed-off-by: Lukasz Majewski <l.majewski@samsung.com> Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Use sizeof(*ptr) convetion for computing sizesViresh Kumar
Chapter 14 of Documentation/CodingStyle says: The preferred form for passing a size of a struct is the following: p = kmalloc(sizeof(*p), ...); The alternative form where struct name is spelled out hurts readability and introduces an opportunity for a bug when the pointer variable type is changed but the corresponding sizeof that is passed to a memory allocator is not. This wasn't followed consistently in drivers/cpufreq, let's make it more consistent by always following this rule. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Give consistent names to cpufreq_policy objectsViresh Kumar
They are called policy, cur_policy, new_policy, data, etc. Just call them policy wherever possible. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Clean up header files included in the coreViresh Kumar
This patch addresses the following issues in the header files in the cpufreq core: - Include headers in ascending order, so that we don't add same many times by mistake. - <asm/> must be included after <linux/>, so that they override whatever they need to. - Remove unnecessary includes. - Don't include files already included by cpufreq.h or cpufreq_governor.h. [rjw: Changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07Merge branch 'pm-cpufreq-ondemand' into pm-cpufreqRafael J. Wysocki
* pm-cpufreq: cpufreq: Remove unused function __cpufreq_driver_getavg() cpufreq: Remove unused APERF/MPERF support cpufreq: ondemand: Change the calculation of target frequency
2013-08-07cpufreq: Pass policy to cpufreq_add_policy_cpu()Viresh Kumar
The caller of cpufreq_add_policy_cpu() already has a pointer to the policy structure and there is no need to look it up again in cpufreq_add_policy_cpu(). Let's pass it directly. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Avoid double kobject_put() for the same kobject in error code pathRafael J. Wysocki
The only case triggering a jump to the err_out_unregister label in __cpufreq_add_dev() is when cpufreq_add_dev_interface() fails. However, if cpufreq_add_dev_interface() fails, it calls kobject_put() for the policy kobject in its error code path and since that causes the kobject's refcount to become 0, the additional kobject_put() for the same kobject under err_out_unregister and the wait_for_completion() following it are pointless, so drop them. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2013-08-07cpufreq: Do not hold driver module references for additional policy CPUsRafael J. Wysocki
The cpufreq core is a little inconsistent in the way it uses the driver module refcount. Namely, if __cpufreq_add_dev() is called for a CPU that doesn't share the policy object with any other CPUs, the driver module refcount it grabs to start with will be dropped by it before returning and will be equal to whatever it had been before that function was invoked. However, if the given CPU does share the policy object with other CPUs, either cpufreq_add_policy_cpu() is called to link the new CPU to the existing policy, or cpufreq_add_dev_symlink() is used to link the other CPUs sharing the policy with it to the just created policy object. In that case, because both cpufreq_add_policy_cpu() and cpufreq_add_dev_symlink() call cpufreq_cpu_get() for the given policy (the latter possibly many times) without the balancing cpufreq_cpu_put() (unless there is an error), the driver module refcount will be left by __cpufreq_add_dev() with a nonzero value (different from the initial one). To remove that inconsistency make cpufreq_add_policy_cpu() execute cpufreq_cpu_put() for the given policy before returning, which decrements the driver module refcount so that it will be equal to its initial value after __cpufreq_add_dev() returns. Also remove the cpufreq_cpu_get() call from cpufreq_add_dev_symlink(), since both the policy refcount and the driver module refcount are nonzero when it is called and they don't need to be bumped up by it. Accordingly, drop the cpufreq_cpu_put() from __cpufreq_remove_dev(), since it is only necessary to balance the cpufreq_cpu_get() called by cpufreq_add_policy_cpu() or cpufreq_add_dev_symlink(). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2013-08-07cpufreq: Don't pass CPU to cpufreq_add_dev_{symlink|interface}()Viresh Kumar
Pointer to struct cpufreq_policy is already passed to these routines and we don't need to send policy->cpu to them as well. So, get rid of this extra argument and use policy->cpu everywhere. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Remove extra variables from cpufreq_add_dev_symlink()Viresh Kumar
We call cpufreq_cpu_get() in cpufreq_add_dev_symlink() to increase usage refcount of policy, but not to get a policy for the given CPU. So, we don't really need to capture the return value of this routine. We can simply use policy passed as an argument to cpufreq_add_dev_symlink(). Moreover debug print is rewritten to make it more clear. [rjw: Changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Perform light-weight init/teardown during suspend/resumeSrivatsa S. Bhat
Now that we have the infrastructure to perform a light-weight init/tear-down, use that in the cpufreq CPU hotplug notifier when invoked from the suspend/resume path. This also ensures that the file permissions of the cpufreq sysfs files are preserved across suspend/resume, something which commit a66b2e (cpufreq: Preserve sysfs files across suspend/resume) originally intended to do, but had to be reverted due to other problems. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Preserve policy structure across suspend/resumeSrivatsa S. Bhat
To perform light-weight cpu-init and teardown in the cpufreq subsystem during suspend/resume, we need to separate out the 2 main functionalities of the cpufreq CPU hotplug callbacks, as outlined below: 1. Init/tear-down of core cpufreq and CPU-specific components, which are critical to the correct functioning of the cpufreq subsystem. 2. Init/tear-down of cpufreq sysfs files during suspend/resume. The first part requires accurate updates to the policy structure such as its ->cpus and ->related_cpus masks, whereas the second part requires that the policy->kobj structure is not released or re-initialized during suspend/resume. To handle both these requirements, we need to allow updates to the policy structure throughout suspend/resume, but prevent the structure from getting freed up. Also, we must have a mechanism by which the cpu-up callbacks can restore the policy structure, without allocating things afresh. (That also helps avoid memory leaks). To achieve this, we use 2 schemes: a. Use a fallback per-cpu storage area for preserving the policy structures during suspend, so that they can be restored during resume appropriately. b. Use the 'frozen' flag to determine when to free or allocate the policy structure vs when to restore the policy from the saved fallback storage. Thus we can successfully preserve the structure across suspend/resume. Effectively, this helps us complete the separation of the 'light-weight' and the 'full' init/tear-down sequences in the cpufreq subsystem, so that this can be made use of in the suspend/resume scenario. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Introduce a flag ('frozen') to separate full vs temporary init/teardownSrivatsa S. Bhat
During suspend/resume we would like to do a light-weight init/teardown of CPUs in the cpufreq subsystem and preserve certain things such as sysfs files etc across suspend/resume transitions. Add a flag called 'frozen' to help distinguish the full init/teardown sequence from the light-weight one. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Extract the handover of policy cpu to a helper functionSrivatsa S. Bhat
During cpu offline, when the policy->cpu is going down, some other CPU present in the policy->cpus mask is nominated as the new policy->cpu. Extract this functionality from __cpufreq_remove_dev() and implement it in a helper function. This helps in upcoming code reorganization. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Extract non-interface related stuff from cpufreq_add_dev_interfaceSrivatsa S. Bhat
cpufreq_add_dev_interface() includes the work of exposing the interface to the device, as well as a lot of unrelated stuff. Move the latter to cpufreq_add_dev(), where it is more appropriate. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Add helper to perform alloc/free of policy structureSrivatsa S. Bhat
Separate out the allocation of the cpufreq policy structure (along with its error handling) to a helper function. This makes the code easier to read and also helps with some upcoming code reorganization. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: Fix misplaced call to cpufreq_update_policy()Srivatsa S. Bhat
The call to cpufreq_update_policy() is placed in the CPU hotplug callback of cpufreq_stats, which has a higher priority than the CPU hotplug callback of cpufreq-core. As a result, during CPU_ONLINE/CPU_ONLINE_FROZEN, we end up calling cpufreq_update_policy() *before* calling cpufreq_add_dev() ! And for uninitialized CPUs, it just returns silently, not doing anything. To add to that, cpufreq_stats is not even the right place to call cpufreq_update_policy() to begin with. The cpufreq core ought to handle this in its own callback, from an elegance/relevance perspective. So move the invocation of cpufreq_update_policy() to cpufreq_cpu_callback, and place it *after* cpufreq_add_dev(). Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: rename ignore_nice as ignore_nice_loadViresh Kumar
This sysfs file was called ignore_nice_load earlier and commit 4d5dcc4 (cpufreq: governor: Implement per policy instances of governors) changed its name to ignore_nice by mistake. Lets get it renamed back to its original name. Reported-by: Martin von Gagern <Martin.vGagern@gmx.net> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: 3.10+ <stable@vger.kernel.org> # 3.10+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07cpufreq: loongson2: fix regression related to clock managementAaro Koskinen
Commit 42913c799 (MIPS: Loongson2: Use clk API instead of direct dereferences) broke the cpufreq functionality on Loongson2 boards: clk_set_rate() is called before the CPU frequency table is initialized, and therefore will always fail. Fix by moving the clk_set_rate() after the table initialization. Tested on Lemote FuLoong mini-PC. Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: 3.9+ <stable@vger.kernel.org> # 3.9+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-29cpufreq: Fix cpufreq driver module refcount balance after suspend/resumeRafael J. Wysocki
Since cpufreq_cpu_put() called by __cpufreq_remove_dev() drops the driver module refcount, __cpufreq_remove_dev() causes that refcount to become negative for the cpufreq driver after a suspend/resume cycle. This is not the only bad thing that happens there, however, because kobject_put() should only be called for the policy kobject at this point if the CPU is not the last one for that policy. Namely, if the given CPU is the last one for that policy, the policy kobject's refcount should be 1 at this point, as set by cpufreq_add_dev_interface(), and only needs to be dropped once for the kobject to go away. This actually happens under the cpu == 1 check, so it need not be done before by cpufreq_cpu_put(). On the other hand, if the given CPU is not the last one for that policy, this means that cpufreq_add_policy_cpu() has been called at least once for that policy and cpufreq_cpu_get() has been called for it too. To balance that cpufreq_cpu_get(), we need to call cpufreq_cpu_put() in that case. Thus, to fix the described problem and keep the reference counters balanced in both cases, move the cpufreq_cpu_get() call in __cpufreq_remove_dev() to the code path executed only for CPUs that share the policy with other CPUs. Reported-and-tested-by: Toralf Förster <toralf.foerster@gmx.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: 3.10+ <stable@vger.kernel.org>
2013-07-25cpufreq: Remove unused function __cpufreq_driver_getavg()Stratos Karafotis
The target frequency calculation method in the ondemand governor has changed and it is now independent of the measured average frequency. Consequently, the __cpufreq_driver_getavg() function and getavg member of struct cpufreq_driver are not used any more, so drop them. [rjw: Changelog] Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-25cpufreq: Remove unused APERF/MPERF supportStratos Karafotis
The target frequency calculation method in the ondemand governor has changed and it is now independent of the measured average frequency. Consequently, the APERF/MPERF support in cpufreq is not used any more, so drop it. [rjw: Changelog] Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-25cpufreq: ondemand: Change the calculation of target frequencyStratos Karafotis
The ondemand governor calculates load in terms of frequency and increases it only if load_freq is greater than up_threshold multiplied by the current or average frequency. This appears to produce oscillations of frequency between min and max because, for example, a relatively small load can easily saturate minimum frequency and lead the CPU to the max. Then, it will decrease back to the min due to small load_freq. Change the calculation method of load and target frequency on the basis of the following two observations: - Load computation should not depend on the current or average measured frequency. For example, absolute load of 80% at 100MHz is not necessarily equivalent to 8% at 1000MHz in the next sampling interval. - It should be possible to increase the target frequency to any value present in the frequency table proportional to the absolute load, rather than to the max only, so that: Target frequency = C * load where we take C = policy->cpuinfo.max_freq / 100. Tested on Intel i7-3770 CPU @ 3.40GHz and on Quad core 1500MHz Krait. Phoronix benchmark of Linux Kernel Compilation 3.1 test shows an increase ~1.5% in performance. cpufreq_stats (time_in_state) shows that middle frequencies are used more, with this patch. Highest and lowest frequencies were used less by ~9%. [rjw: We have run multiple other tests on kernels with this change applied and in the vast majority of cases it turns out that the resulting performance improvement also leads to reduced consumption of energy. The change is additionally justified by the overall simplification of the code in question.] Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-23cpufreq / intel_pstate: Change to scale off of max P-stateDirk Brandewie
Change to using max P-state instead of max turbo P-state. This change resolves two issues. On a quiet system intel_pstate can fail to respond to a load change. On CPU SKUs that have a limited number of P-states and no turbo range intel_pstate fails to select the highest available P-state. This change is suitable for stable v3.9+ References: https://bugzilla.kernel.org/show_bug.cgi?id=59481 Reported-and-tested-by: Arjan van de Ven <arjan@linux.intel.com> Reported-and-tested-by: dsmythies@telus.net Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: 3.9+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>