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2013-09-25cpufreq: exynos5440: Fix potential NULL pointer dereferenceSachin Kamat1-1/+1
If 'dvfs_info' is NULL (due to devm_kzalloc failure) the failure error message would try to dereference it. Use 'pdev' instead. Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-25cpufreq: check cpufreq driver is valid and cpufreq isn't disabled in cpufreq_get()Viresh Kumar1-0/+3
cpufreq_get() can be called from external drivers which might not be aware if cpufreq driver is registered or not. And so we should actually check if cpufreq driver is registered or not and also if cpufreq is active or disabled, at the beginning of cpufreq_get(). Otherwise call to lock_policy_rwsem_read() might hit BUG_ON(!policy). Reported-and-tested-by: Linus Walleij <linus.walleij@linaro.org> 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>
2013-09-25acpi-cpufreq: skip loading acpi_cpufreq after intel_pstateYinghai Lu1-0/+4
If the hw supports intel_pstate and acpi_cpufreq, intel_pstate will get loaded first. acpi_cpufreq_init() will call acpi_cpufreq_early_init() and that will allocate perf data and init those perf data in ACPI core, (that will cover all CPUs). But later it will free them as cpufreq_register_driver(acpi_cpufreq) will fail as intel_pstate is already registered Use cpufreq_get_current_driver() to check if we can skip the acpi_cpufreq loading. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-20cpufreq: return EEXIST instead of EBUSY for second registeringYinghai Lu1-1/+1
On systems that support intel_pstate, acpi_cpufreq fails to load, and udev keeps trying until trace gets filled up and kernel crashes. The root cause is driver return ret from cpufreq_register_driver(), because when some other driver takes over before, it will return EBUSY and then udev will keep trying ... cpufreq_register_driver() should return EEXIST instead so that the system can boot without appending intel_pstate=disable and still use intel_pstate. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-19cpufreq: imx6q-cpufreq: assign cpu_dev correctly to cpu0 deviceSudeep KarkadaNagesha1-1/+6
Commit cdc58d602d2e657602a90c190cbf745886c95977 "cpufreq: imx6q-cpufreq: remove device tree parsing for cpu nodes" assumed the pdev->dev is set to cpu0 device in the platform code. But it actually points to the virtual cpufreq-cpu0 platform device which is not present in the device tree. Most of the information needed by cpufreq is stored in cpu0 DT node. So cpu_dev must point to cpu0 device. This patch fixes the wrong assignment to cpu_dev. Reported-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Tested-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-19cpufreq: cpufreq-cpu0: assign cpu_dev correctly to cpu0 deviceSudeep KarkadaNagesha1-1/+6
Commit f837a9b5ab05c52a07108c6f09ca66f2e0aee757 "cpufreq: cpufreq-cpu0: remove device tree parsing for cpu nodes" assumed the pdev->dev is set to cpu0 device in the platform code. But it actually points to the virtual cpufreq-cpu0 platform device which is not present in the device tree. Most of the information needed by cpufreq is stored in cpu0 DT node. So cpu_dev must point to cpu0 device. This patch fixes the wrong assignment to cpu_dev. Reported-and-tested-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Cc: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-18cpufreq: unlock correct rwsem while updating policy->cpuViresh Kumar1-2/+11
Current code looks like this: WARN_ON(lock_policy_rwsem_write(cpu)); update_policy_cpu(policy, new_cpu); unlock_policy_rwsem_write(cpu); {lock|unlock}_policy_rwsem_write(cpu) takes/releases policy->cpu's rwsem. Because cpu is changing with the call to update_policy_cpu(), the unlock_policy_rwsem_write() will release the incorrect lock. The right solution would be to release the same lock as was taken earlier. Also update_policy_cpu() was also called from cpufreq_add_dev() without any locks and so its better if we move this locking to inside update_policy_cpu(). This patch fixes a regression introduced in 3.12 by commit f9ba680d23 (cpufreq: Extract the handover of policy cpu to a helper function). Reported-and-tested-by: Jon Medhurst<tixy@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-18cpufreq: Clear policy->cpus bits in __cpufreq_remove_dev_finish()Viresh Kumar1-8/+8
This broke after a recent change "cedb70a cpufreq: Split __cpufreq_remove_dev() into two parts" from Srivatsa. Consider a scenario where we have two CPUs in a policy (0 & 1) and we are removing CPU 1. On the call to __cpufreq_remove_dev_prepare() we have cleared 1 from policy->cpus and now on a call to __cpufreq_remove_dev_finish() we read cpumask_weight of policy->cpus, which will come as 1 and this code will behave as if we are removing the last CPU from policy :) Fix it by clearing the CPU mask in __cpufreq_remove_dev_finish() instead of __cpufreq_remove_dev_prepare(). Tested-by: Stephen Warren <swarren@wwwdotorg.org> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-12Merge branch 'pm-cpufreq'Rafael J. Wysocki1-17/+32
* pm-cpufreq: 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
2013-09-11cpufreq: Acquire the lock in cpufreq_policy_restore() for readingLan Tianyu1-2/+2
In cpufreq_policy_restore() before system suspend policy is read from percpu's cpufreq_cpu_data_fallback. It's a read operation rather than a write one, so take the lock for reading in there. Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Reviewed-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>
2013-09-11cpufreq: Prevent problems in update_policy_cpu() if last_cpu == new_cpuSrivatsa S. Bhat1-0/+3
If update_policy_cpu() is invoked with the existing policy->cpu itself as the new-cpu parameter, then a lot of things can go terribly wrong. In its present form, update_policy_cpu() always assumes that the new-cpu is different from policy->cpu and invokes other functions to perform their respective updates. And those functions implement the actual update like this: per_cpu(..., new_cpu) = per_cpu(..., last_cpu); per_cpu(..., last_cpu) = NULL; Thus, when new_cpu == last_cpu, the final NULL assignment makes the per-cpu references vanish into thin air! (memory leak). From there, it leads to more problems: cpufreq_stats_create_table() now doesn't find the per-cpu reference and hence tries to create a new sysfs-group; but sysfs already had created the group earlier, so it complains that it cannot create a duplicate filename. In short, the repercussions of a rather innocuous invocation of update_policy_cpu() can turn out to be pretty nasty. Ideally update_policy_cpu() should handle this situation (new == last) gracefully, and not lead to such severe problems. So fix it by adding an appropriate check. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-11cpufreq: Restructure if/else block to avoid unintended behaviorSrivatsa S. Bhat1-2/+3
In __cpufreq_remove_dev_prepare(), the code which decides whether to remove the sysfs link or nominate a new policy cpu, is governed by an if/else block with a rather complex set of conditionals. Worse, they harbor a subtlety which leads to certain unintended behavior. The code looks like this: if (cpu != policy->cpu && !frozen) { sysfs_remove_link(&dev->kobj, "cpufreq"); } else if (cpus > 1) { new_cpu = cpufreq_nominate_new_policy_cpu(...); ... update_policy_cpu(..., new_cpu); } The original intention was: If the CPU going offline is not policy->cpu, just remove the link. On the other hand, if the CPU going offline is the policy->cpu itself, handover the policy->cpu job to some other surviving CPU in that policy. But because the 'if' condition also includes the 'frozen' check, now there are *two* possibilities by which we can enter the 'else' block: 1. cpu == policy->cpu (intended) 2. cpu != policy->cpu && frozen (unintended) Due to the second (unintended) scenario, we end up spuriously nominating a CPU as the policy->cpu, even when the existing policy->cpu is alive and well. This can cause problems further down the line, especially when we end up nominating the same policy->cpu as the new one (ie., old == new), because it totally confuses update_policy_cpu(). To avoid this mess, restructure the if/else block to only do what was originally intended, and thus prevent any unwelcome surprises. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-11cpufreq: Fix crash in cpufreq-stats during suspend/resumeSrivatsa S. Bhat1-13/+24
Stephen Warren reported that the cpufreq-stats code hits a NULL pointer dereference during the second attempt to suspend a system. He also pin-pointed the problem to commit 5302c3f "cpufreq: Perform light-weight init/teardown during suspend/resume". That commit actually ensured that the cpufreq-stats table and the cpufreq-stats sysfs entries are *not* torn down (ie., not freed) during suspend/resume, which makes it all the more surprising. However, it turns out that the root-cause is not that we access an already freed memory, but that the reference to the allocated memory gets moved around and we lose track of that during resume, leading to the reported crash in a subsequent suspend attempt. In the suspend path, during CPU offline, the value of policy->cpu is updated by choosing one of the surviving CPUs in that policy, as long as there is atleast one CPU in that policy. And cpufreq_stats_update_policy_cpu() is invoked to update the reference to the stats structure by assigning it to the new CPU. However, in the resume path, during CPU online, we end up assigning a fresh CPU as the policy->cpu, without letting cpufreq-stats know about this. Thus the reference to the stats structure remains (incorrectly) associated with the old CPU. So, in a subsequent suspend attempt, during CPU offline, we end up accessing an incorrect location to get the stats structure, which eventually leads to the NULL pointer dereference. Fix this by letting cpufreq-stats know about the update of the policy->cpu during CPU online in the resume path. (Also, move the update_policy_cpu() function higher up in the file, so that __cpufreq_add_dev() can invoke it). Reported-and-tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-11Merge branch 'pm-cpufreq'Rafael J. Wysocki3-34/+76
* pm-cpufreq: 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
2013-09-10intel_pstate: Add Haswell CPU modelsNell Hardcastle1-0/+5
Enable the intel_pstate driver for Haswell CPUs. One missing Ivy Bridge model (0x3E) is also included. Models referenced from tools/power/x86/turbostat/turbostat.c:has_nehalem_turbo_ratio_limit Signed-off-by: Nell Hardcastle <nell@spicious.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Dirk Brandewie <dirk.j.brandewie@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10Revert "cpufreq: make sure frequency transitions are serialized"Rafael J. Wysocki1-15/+0
Commit 7c30ed5 (cpufreq: make sure frequency transitions are serialized) attempted to serialize frequency transitions by adding checks to the CPUFREQ_PRECHANGE and CPUFREQ_POSTCHANGE notifications. However, it assumed that the notifications will always originate from the driver's .target() callback, but they also can be triggered by cpufreq_out_of_sync() and that leads to warnings like this on some systems: WARNING: CPU: 0 PID: 14543 at drivers/cpufreq/cpufreq.c:317 __cpufreq_notify_transition+0x238/0x260() In middle of another frequency transition accompanied by a call trace similar to this one: [<ffffffff81720daa>] dump_stack+0x46/0x58 [<ffffffff8106534c>] warn_slowpath_common+0x8c/0xc0 [<ffffffff815b8560>] ? acpi_cpufreq_target+0x320/0x320 [<ffffffff81065436>] warn_slowpath_fmt+0x46/0x50 [<ffffffff815b1ec8>] __cpufreq_notify_transition+0x238/0x260 [<ffffffff815b33be>] cpufreq_notify_transition+0x3e/0x70 [<ffffffff815b345d>] cpufreq_out_of_sync+0x6d/0xb0 [<ffffffff815b370c>] cpufreq_update_policy+0x10c/0x160 [<ffffffff815b3760>] ? cpufreq_update_policy+0x160/0x160 [<ffffffff81413813>] cpufreq_set_cur_state+0x8c/0xb5 [<ffffffff814138df>] processor_set_cur_state+0xa3/0xcf [<ffffffff8158e13c>] thermal_cdev_update+0x9c/0xb0 [<ffffffff8159046a>] step_wise_throttle+0x5a/0x90 [<ffffffff8158e21f>] handle_thermal_trip+0x4f/0x140 [<ffffffff8158e377>] thermal_zone_device_update+0x57/0xa0 [<ffffffff81415b36>] acpi_thermal_check+0x2e/0x30 [<ffffffff81415ca0>] acpi_thermal_notify+0x40/0xdc [<ffffffff813e7dbd>] acpi_device_notify+0x19/0x1b [<ffffffff813f8241>] acpi_ev_notify_dispatch+0x41/0x5c [<ffffffff813e3fbe>] acpi_os_execute_deferred+0x25/0x32 [<ffffffff81081060>] process_one_work+0x170/0x4a0 [<ffffffff81082121>] worker_thread+0x121/0x390 [<ffffffff81082000>] ? manage_workers.isra.20+0x170/0x170 [<ffffffff81088fe0>] kthread+0xc0/0xd0 [<ffffffff81088f20>] ? flush_kthread_worker+0xb0/0xb0 [<ffffffff8173582c>] ret_from_fork+0x7c/0xb0 [<ffffffff81088f20>] ? flush_kthread_worker+0xb0/0xb0 For this reason, revert commit 7c30ed5 along with the fix 266c13d (cpufreq: Fix serialization of frequency transitions) on top of it and we will revisit the serialization problem later. Reported-by: Alessandro Bono <alessandro.bono@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10cpufreq: Use signed type for 'ret' variable, to store negative error valuesSrivatsa S. Bhat1-2/+2
There are places where the variable 'ret' is declared as unsigned int and then used to store negative return values such as -EINVAL. Fix them by declaring the variable as a signed quantity. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10cpufreq: Remove temporary fix for race between CPU hotplug and sysfs-writesSrivatsa S. Bhat1-6/+1
Commit "cpufreq: serialize calls to __cpufreq_governor()" had been a temporary and partial solution to the race condition between writing to a cpufreq sysfs file and taking a CPU offline. Now that we have a proper and complete solution to that problem, remove the temporary fix. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10cpufreq: Synchronize the cpufreq store_*() routines with CPU hotplugSrivatsa S. Bhat1-2/+9
The functions that are used to write to cpufreq sysfs files (such as store_scaling_max_freq()) are not hotplug safe. They can race with CPU hotplug tasks and lead to problems such as trying to acquire an already destroyed timer-mutex etc. Eg: __cpufreq_remove_dev() __cpufreq_governor(policy, CPUFREQ_GOV_STOP); policy->governor->governor(policy, CPUFREQ_GOV_STOP); cpufreq_governor_dbs() case CPUFREQ_GOV_STOP: mutex_destroy(&cpu_cdbs->timer_mutex) cpu_cdbs->cur_policy = NULL; <PREEMPT> store() __cpufreq_set_policy() __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); policy->governor->governor(policy, CPUFREQ_GOV_LIMITS); case CPUFREQ_GOV_LIMITS: mutex_lock(&cpu_cdbs->timer_mutex); <-- Warning (destroyed mutex) if (policy->max < cpu_cdbs->cur_policy->cur) <- cur_policy == NULL So use get_online_cpus()/put_online_cpus() in the store_*() functions, to synchronize with CPU hotplug. However, there is an additional point to note here: some parts of the CPU teardown in the cpufreq subsystem are done in the CPU_POST_DEAD stage, with cpu_hotplug.lock *released*. So, using the get/put_online_cpus() functions alone is insufficient; we should also ensure that we don't race with those latter steps in the hotplug sequence. We can easily achieve this by checking if the CPU is online before proceeding with the store, since the CPU would have been marked offline by the time the CPU_POST_DEAD notifiers are executed. Reported-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10cpufreq: Invoke __cpufreq_remove_dev_finish() after releasing cpu_hotplug.lockSrivatsa S. Bhat1-0/+3
__cpufreq_remove_dev_finish() handles the kobject cleanup for a CPU going offline. But because we destroy the kobject towards the end of the CPU offline phase, there are certain race windows where a task can try to write to a cpufreq sysfs file (eg: using store_scaling_max_freq()) while we are taking that CPU offline, and this can bump up the kobject refcount, which in turn might hinder the CPU offline task from running to completion. (It can also cause other more serious problems such as trying to acquire a destroyed timer-mutex etc., depending on the exact stage of the cleanup at which the task managed to take a new refcount). To fix the race window, we will need to synchronize those store_*() call-sites with CPU hotplug, using get_online_cpus()/put_online_cpus(). However, that in turn can cause a total deadlock because it can end up waiting for the CPU offline task to complete, with incremented refcount! Write to sysfs CPU offline task -------------- ---------------- kobj_refcnt++ Acquire cpu_hotplug.lock get_online_cpus(); Wait for kobj_refcnt to drop to zero **DEADLOCK** A simple way to avoid this problem is to perform the kobject cleanup in the CPU offline path, with the cpu_hotplug.lock *released*. That is, we can perform the wait-for-kobj-refcnt-to-drop as well as the subsequent cleanup in the CPU_POST_DEAD stage of CPU offline, which is run with cpu_hotplug.lock released. Doing this helps us avoid deadlocks due to holding kobject refcounts and waiting on each other on the cpu_hotplug.lock. (Note: We can't move all of the cpufreq CPU offline steps to the CPU_POST_DEAD stage, because certain things such as stopping the governors have to be done before the outgoing CPU is marked offline. So retain those parts in the CPU_DOWN_PREPARE stage itself). Reported-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10cpufreq: Split __cpufreq_remove_dev() into two partsSrivatsa S. Bhat1-12/+53
During CPU offline, the cpufreq core invokes __cpufreq_remove_dev() to perform work such as stopping the cpufreq governor, clearing the CPU from the policy structure etc, and finally cleaning up the kobject. There are certain subtle issues related to the kobject cleanup, and it would be much easier to deal with them if we separate that part from the rest of the cleanup-work in the CPU offline phase. So split the __cpufreq_remove_dev() function into 2 parts: one that handles the kobject cleanup, and the other that handles the rest of the work. Reported-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10cpufreq: Fix wrong time unit conversionAndreas Schwab1-1/+1
The time spent by a CPU under a given frequency is stored in jiffies unit in the cpu var cpufreq_stats_table->time_in_state[i], i being the index of the frequency. This is what is displayed in the following file on the right column: cat /sys/devices/system/cpu/cpuX/cpufreq/stats/time_in_state 2301000 19835820 2300000 3172 [...] Now cpufreq converts this jiffies unit delta to clock_t before returning it to the user as in the above file. And that conversion is achieved using the API cputime64_to_clock_t(). Although it accidentally works on traditional tick based cputime accounting, where cputime_t maps directly to jiffies, it doesn't work with other types of cputime accounting such as CONFIG_VIRT_CPU_ACCOUNTING_* where cputime_t can map to nsecs or any granularity preffered by the architecture. For example we get a buggy zero delta on full dyntick configurations: cat /sys/devices/system/cpu/cpuX/cpufreq/stats/time_in_state 2301000 0 2300000 0 [...] Fix this with using the proper jiffies_64_t to clock_t conversion. Reported-and-tested-by: Carsten Emde <C.Emde@osadl.org> Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10cpufreq: serialize calls to __cpufreq_governor()Viresh Kumar1-1/+6
We can't take a big lock around __cpufreq_governor() as this causes recursive locking for some cases. But calls to this routine must be serialized for every policy. Otherwise we can see some unpredictable events. For example, consider following scenario: __cpufreq_remove_dev() __cpufreq_governor(policy, CPUFREQ_GOV_STOP); policy->governor->governor(policy, CPUFREQ_GOV_STOP); cpufreq_governor_dbs() case CPUFREQ_GOV_STOP: mutex_destroy(&cpu_cdbs->timer_mutex) cpu_cdbs->cur_policy = NULL; <PREEMPT> store() __cpufreq_set_policy() __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); policy->governor->governor(policy, CPUFREQ_GOV_LIMITS); case CPUFREQ_GOV_LIMITS: mutex_lock(&cpu_cdbs->timer_mutex); <-- Warning (destroyed mutex) if (policy->max < cpu_cdbs->cur_policy->cur) <- cur_policy == NULL And so store() will eventually result in a crash if cur_policy is NULL at this point. Introduce an additional variable which would guarantee serialization here. Reported-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10cpufreq: don't allow governor limits to be changed when it is disabledViresh Kumar1-2/+3
__cpufreq_governor() returns with -EBUSY when governor is already stopped and we try to stop it again, but when it is stopped we must not allow calls to CPUFREQ_GOV_LIMITS event as well. This patch adds this check in __cpufreq_governor(). Reported-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-03Merge tag 'pm+acpi-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds61-771/+581
Pull ACPI and power management updates from Rafael Wysocki: 1) ACPI-based PCI hotplug (ACPIPHP) subsystem rework and introduction of Intel Thunderbolt support on systems that use ACPI for signalling Thunderbolt hotplug events. This also should make ACPIPHP work in some cases in which it was known to have problems. From Rafael J Wysocki, Mika Westerberg and Kirill A Shutemov. 2) ACPI core code cleanups and dock station support cleanups from Jiang Liu and Rafael J Wysocki. 3) Fixes for locking problems related to ACPI device hotplug from Rafael J Wysocki. 4) ACPICA update to version 20130725 includig fixes, cleanups, support for more than 256 GPEs per GPE block and a change to make the ACPI PM Timer optional (we've seen systems without the PM Timer in the field already). One of the fixes, related to the DeRefOf operator, is necessary to prevent some Windows 8 oriented AML from causing problems to happen. From Bob Moore, Lv Zheng, and Jung-uk Kim. 5) Removal of the old and long deprecated /proc/acpi/event interface and related driver changes from Thomas Renninger. 6) ACPI and Xen changes to make the reduced hardware sleep work with the latter from Ben Guthro. 7) ACPI video driver cleanups and a blacklist of systems that should not tell the BIOS that they are compatible with Windows 8 (or ACPI backlight and possibly other things will not work on them). From Felipe Contreras. 8) Assorted ACPI fixes and cleanups from Aaron Lu, Hanjun Guo, Kuppuswamy Sathyanarayanan, Lan Tianyu, Sachin Kamat, Tang Chen, Toshi Kani, and Wei Yongjun. 9) cpufreq ondemand governor target frequency selection change to reduce oscillations between min and max frequencies (essentially, it causes the governor to choose target frequencies proportional to load) from Stratos Karafotis. 10) cpufreq fixes allowing sysfs attributes file permissions to be preserved over suspend/resume cycles Srivatsa S Bhat. 11) Removal of Device Tree parsing for CPU device nodes from multiple cpufreq drivers that required some changes related to of_get_cpu_node() to be made in a few architectures and in the driver core. From Sudeep KarkadaNagesha. 12) cpufreq core fixes and cleanups related to mutual exclusion and driver module references from Viresh Kumar, Lukasz Majewski and Rafael J Wysocki. 13) Assorted cpufreq fixes and cleanups from Amit Daniel Kachhap, Bartlomiej Zolnierkiewicz, Hanjun Guo, Jingoo Han, Joseph Lo, Julia Lawall, Li Zhong, Mark Brown, Sascha Hauer, Stephen Boyd, Stratos Karafotis, and Viresh Kumar. 14) Fixes to prevent race conditions in coupled cpuidle from happening from Colin Cross. 15) cpuidle core fixes and cleanups from Daniel Lezcano and Tuukka Tikkanen. 16) Assorted cpuidle fixes and cleanups from Daniel Lezcano, Geert Uytterhoeven, Jingoo Han, Julia Lawall, Linus Walleij, and Sahara. 17) System sleep tracing changes from Todd E Brandt and Shuah Khan. 18) PNP subsystem conversion to using struct dev_pm_ops for power management from Shuah Khan. * tag 'pm+acpi-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (217 commits) cpufreq: Don't use smp_processor_id() in preemptible context cpuidle: coupled: fix race condition between pokes and safe state cpuidle: coupled: abort idle if pokes are pending cpuidle: coupled: disable interrupts after entering safe state ACPI / hotplug: Remove containers synchronously driver core / ACPI: Avoid device hot remove locking issues cpufreq: governor: Fix typos in comments cpufreq: governors: Remove duplicate check of target freq in supported range cpufreq: Fix timer/workqueue corruption due to double queueing ACPI / EC: Add ASUSTEK L4R to quirk list in order to validate ECDT ACPI / thermal: Add check of "_TZD" availability and evaluating result cpufreq: imx6q: Fix clock enable balance ACPI: blacklist win8 OSI for buggy laptops cpufreq: tegra: fix the wrong clock name cpuidle: Change struct menu_device field types cpuidle: Add a comment warning about possible overflow cpuidle: Fix variable domains in get_typical_interval() cpuidle: Fix menu_device->intervals type cpuidle: CodingStyle: Break up multiple assignments on single line cpuidle: Check called function parameter in get_typical_interval() ...
2013-09-01Merge remote-tracking branch 'regulator/topic/optional' into regulator-nextMark Brown1-1/+1
2013-08-29cpufreq: Don't use smp_processor_id() in preemptible contextStephen Boyd1-1/+8
Workqueues are preemptible even if works are queued on them with queue_work_on(). Let's use raw_smp_processor_id() here to silence the warning. BUG: using smp_processor_id() in preemptible [00000000] code: kworker/3:2/674 caller is gov_queue_work+0x28/0xb0 CPU: 0 PID: 674 Comm: kworker/3:2 Tainted: G W 3.10.0 #30 Workqueue: events od_dbs_timer [<c010c178>] (unwind_backtrace+0x0/0x11c) from [<c0109dec>] (show_stack+0x10/0x14) [<c0109dec>] (show_stack+0x10/0x14) from [<c03885a4>] (debug_smp_processor_id+0xbc/0xf0) [<c03885a4>] (debug_smp_processor_id+0xbc/0xf0) from [<c0635864>] (gov_queue_work+0x28/0xb0) [<c0635864>] (gov_queue_work+0x28/0xb0) from [<c0635618>] (od_dbs_timer+0x108/0x134) [<c0635618>] (od_dbs_timer+0x108/0x134) from [<c01aa8f8>] (process_one_work+0x25c/0x444) [<c01aa8f8>] (process_one_work+0x25c/0x444) from [<c01aaf88>] (worker_thread+0x200/0x344) [<c01aaf88>] (worker_thread+0x200/0x344) from [<c01b03bc>] (kthread+0xa0/0xb0) [<c01b03bc>] (kthread+0xa0/0xb0) from [<c01061b8>] (ret_from_fork+0x14/0x3c) Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-28cpufreq: governor: Fix typos in commentsStratos Karafotis2-7/+7
- 'Governer' should be 'Governor'. - 'S' is used for Siemens (electrical conductance) in SI units, so use small 's' for seconds. 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>
2013-08-28cpufreq: governors: Remove duplicate check of target freq in supported rangeStratos Karafotis2-7/+0
Function __cpufreq_driver_target() checks if target_freq is within policy->min and policy->max range. generic_powersave_bias_target() also checks if target_freq is valid via a cpufreq_frequency_table_target() call. So, drop the unnecessary duplicate check in *_check_cpu(). 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>
2013-08-28cpufreq: Fix timer/workqueue corruption due to double queueingStephen Boyd1-0/+3
When a CPU is hot removed we'll cancel all the delayed work items via gov_cancel_work(). Normally this will just cancels a delayed timer on each CPU that the policy is managing and the work won't run, but if the work is already running the workqueue code will wait for the work to finish before continuing to prevent the work items from re-queuing themselves like they normally do. This scheme will work most of the time, except for the case where the work function determines that it should adjust the delay for all other CPUs that the policy is managing. If this scenario occurs, the canceling CPU will cancel its own work but queue up the other CPUs works to run. For example: CPU0 CPU1 ---- ---- cpu_down() ... __cpufreq_remove_dev() cpufreq_governor_dbs() case CPUFREQ_GOV_STOP: gov_cancel_work(dbs_data, policy); cpu0 work is canceled timer is canceled cpu1 work is canceled <work runs> <waits for cpu1> od_dbs_timer() gov_queue_work(*, *, true); cpu0 work queued cpu1 work queued cpu2 work queued ... cpu1 work is canceled cpu2 work is canceled ... At the end of the GOV_STOP case cpu0 still has a work queued to run although the code is expecting all of the works to be canceled. __cpufreq_remove_dev() will then proceed to re-initialize all the other CPUs works except for the CPU that is going down. The CPUFREQ_GOV_START case in cpufreq_governor_dbs() will trample over the queued work and debugobjects will spit out a warning: WARNING: at lib/debugobjects.c:260 debug_print_object+0x94/0xbc() ODEBUG: init active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x10 Modules linked in: CPU: 0 PID: 1491 Comm: sh Tainted: G W 3.10.0 #19 [<c010c178>] (unwind_backtrace+0x0/0x11c) from [<c0109dec>] (show_stack+0x10/0x14) [<c0109dec>] (show_stack+0x10/0x14) from [<c01904cc>] (warn_slowpath_common+0x4c/0x6c) [<c01904cc>] (warn_slowpath_common+0x4c/0x6c) from [<c019056c>] (warn_slowpath_fmt+0x2c/0x3c) [<c019056c>] (warn_slowpath_fmt+0x2c/0x3c) from [<c0388a7c>] (debug_print_object+0x94/0xbc) [<c0388a7c>] (debug_print_object+0x94/0xbc) from [<c0388e34>] (__debug_object_init+0x2d0/0x340) [<c0388e34>] (__debug_object_init+0x2d0/0x340) from [<c019e3b0>] (init_timer_key+0x14/0xb0) [<c019e3b0>] (init_timer_key+0x14/0xb0) from [<c0635f78>] (cpufreq_governor_dbs+0x3e8/0x5f8) [<c0635f78>] (cpufreq_governor_dbs+0x3e8/0x5f8) from [<c06325a0>] (__cpufreq_governor+0xdc/0x1a4) [<c06325a0>] (__cpufreq_governor+0xdc/0x1a4) from [<c0633704>] (__cpufreq_remove_dev.isra.10+0x3b4/0x434) [<c0633704>] (__cpufreq_remove_dev.isra.10+0x3b4/0x434) from [<c08989f4>] (cpufreq_cpu_callback+0x60/0x80) [<c08989f4>] (cpufreq_cpu_callback+0x60/0x80) from [<c08a43c0>] (notifier_call_chain+0x38/0x68) [<c08a43c0>] (notifier_call_chain+0x38/0x68) from [<c01938e0>] (__cpu_notify+0x28/0x40) [<c01938e0>] (__cpu_notify+0x28/0x40) from [<c0892ad4>] (_cpu_down+0x7c/0x2c0) [<c0892ad4>] (_cpu_down+0x7c/0x2c0) from [<c0892d3c>] (cpu_down+0x24/0x40) [<c0892d3c>] (cpu_down+0x24/0x40) from [<c0893ea8>] (store_online+0x2c/0x74) [<c0893ea8>] (store_online+0x2c/0x74) from [<c04519d8>] (dev_attr_store+0x18/0x24) [<c04519d8>] (dev_attr_store+0x18/0x24) from [<c02a69d4>] (sysfs_write_file+0x100/0x148) [<c02a69d4>] (sysfs_write_file+0x100/0x148) from [<c0255c18>] (vfs_write+0xcc/0x174) [<c0255c18>] (vfs_write+0xcc/0x174) from [<c0255f70>] (SyS_write+0x38/0x64) [<c0255f70>] (SyS_write+0x38/0x64) from [<c0106120>] (ret_fast_syscall+0x0/0x30) Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-27Merge branch 'cpufreq-fixes' of git://git.linaro.org/people/vireshk/linux into pm-cpufreqRafael J. Wysocki2-19/+2
Pull cpufreq fixes for v3.12 from Viresh Kumar. * 'cpufreq-fixes' of git://git.linaro.org/people/vireshk/linux: cpufreq: imx6q: Fix clock enable balance cpufreq: tegra: fix the wrong clock name
2013-08-26cpufreq: imx6q: Fix clock enable balanceSascha Hauer1-17/+0
For changing the cpu frequency the i.MX6q has to be switched to some intermediate clock during the PLL reprogramming. The driver tries to be clever to keep the enable count correct but gets it wrong. If the cpufreq is increased it calls clk_disable_unprepare twice on pll2_pfd2_396m. This puts all other devices which get their clock from pll2_pfd2_396m into a nonworking state. Fix this by removing the clk enabling/disabling altogether since the clk core will do this automatically during a reparent. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2013-08-23cpufreq: tegra: fix the wrong clock nameJoseph Lo1-2/+2
The "cpu" and "pclk_p_cclk" was a virtual clock name that was used in the legacy Tegra clock framework. It was not used after converting to CCF. Fix it as the correct clock name that we are using. Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Joseph Lo <josephl@nvidia.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2013-08-23Merge branch 'cpu_of_node' of git://linux-arm.org/linux-skn into pm-cpufreq-nextRafael J. Wysocki9-123/+49
Pull DT/core/cpufreq cpu_ofnode updates for v3.12 from Sudeep KarkadaNagesha. * 'cpu_of_node' of git://linux-arm.org/linux-skn: cpufreq: pmac32-cpufreq: remove device tree parsing for cpu nodes cpufreq: pmac64-cpufreq: remove device tree parsing for cpu nodes cpufreq: maple-cpufreq: remove device tree parsing for cpu nodes cpufreq: arm_big_little: remove device tree parsing for cpu nodes cpufreq: kirkwood-cpufreq: remove device tree parsing for cpu nodes cpufreq: spear-cpufreq: remove device tree parsing for cpu nodes cpufreq: highbank-cpufreq: remove device tree parsing for cpu nodes cpufreq: cpufreq-cpu0: remove device tree parsing for cpu nodes cpufreq: imx6q-cpufreq: remove device tree parsing for cpu nodes drivers/bus: arm-cci: avoid parsing DT for cpu device nodes ARM: mvebu: remove device tree parsing for cpu nodes ARM: topology: remove hwid/MPIDR dependency from cpu_capacity of/device: add helper to get cpu device node from logical cpu index driver/core: cpu: initialize of_node in cpu's device struture ARM: DT/kernel: define ARM specific arch_match_cpu_phys_id of: move of_get_cpu_node implementation to DT core library powerpc: refactor of_get_cpu_node to support other architectures openrisc: remove undefined of_get_cpu_node declaration microblaze: remove undefined of_get_cpu_node declaration
2013-08-21cpufreq: pmac32-cpufreq: remove device tree parsing for cpu nodesSudeep KarkadaNagesha1-2/+3
Now that the cpu device registration initialises the of_node(if available) appropriately for all the cpus, parsing here is redundant. This patch removes DT parsing and uses cpu->of_node instead. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
2013-08-21cpufreq: pmac64-cpufreq: remove device tree parsing for cpu nodesSudeep KarkadaNagesha1-36/+11
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. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
2013-08-21cpufreq: maple-cpufreq: remove device tree parsing for cpu nodesSudeep KarkadaNagesha1-20/+3
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. Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
2013-08-21cpufreq: arm_big_little: remove device tree parsing for cpu nodesSudeep KarkadaNagesha1-26/+14
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: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
2013-08-21cpufreq: kirkwood-cpufreq: remove device tree parsing for cpu nodesSudeep KarkadaNagesha1-3/+5
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. Cc: Jason Cooper <jason@lakedaemon.net> Acked-by: Andrew Lunn <andrew@lunn.ch> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
2013-08-21cpufreq: spear-cpufreq: remove device tree parsing for cpu nodesSudeep KarkadaNagesha1-2/+2
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. Cc: Deepak Sikri <sikrid@qti.qualcomm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
2013-08-21cpufreq: highbank-cpufreq: remove device tree parsing for cpu nodesSudeep KarkadaNagesha1-12/+6
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. Cc: Mark Langsdorf <mark.langsdorf@calxeda.com> 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: cpufreq-cpu0: remove device tree parsing for cpu nodesSudeep KarkadaNagesha1-19/+4
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 KarkadaNagesha1-3/+1
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 Zhong1-1/+1
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 Kumar1-5/+4
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 Kumar1-35/+10
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 Kumar1-2/+0
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 Kumar1-10/+9
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 Kumar1-1/+1
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. Wysocki1-4/+5
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