summaryrefslogtreecommitdiff
path: root/drivers/cpufreq/cpufreq_stats.c
AgeCommit message (Collapse)Author
2016-11-11cpufreq: stats: New sysfs attribute for clearing statisticsMarkus Mayer
Allow CPUfreq statistics to be cleared by writing anything to /sys/.../cpufreq/stats/reset. Signed-off-by: Markus Mayer <mmayer@broadcom.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-09cpufreq: Remove cpufreq_frequency_get_table()Viresh Kumar
Most of the callers of cpufreq_frequency_get_table() already have the pointer to a valid 'policy' structure and they don't really need to go through the per-cpu variable first and then a check to validate the frequency, in order to find the freq-table for the policy. Directly use the policy->freq_table field instead for them. Only one user of that API is left after above changes, cpu_cooling.c and it accesses the freq_table in a racy way as the policy can get freed in between. Fix it by using cpufreq_cpu_get() properly. Since there are no more users of cpufreq_frequency_get_table() left, get rid of it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Javi Merino <javi.merino@arm.com> (cpu_cooling.c) Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-02cpufreq: stats: Make the stats code non-modularRafael J. Wysocki
The modularity of cpufreq_stats is quite problematic. First off, the usage of policy notifiers for the initialization and cleanup in the cpufreq_stats module is inherently racy with respect to CPU offline/online and the initialization and cleanup of the cpufreq driver. Second, fast frequency switching (used by the schedutil governor) cannot be enabled if any transition notifiers are registered, so if the cpufreq_stats module (that registers a transition notifier for updating transition statistics) is loaded, the schedutil governor cannot use fast frequency switching. On the other hand, allowing cpufreq_stats to be built as a module doesn't really add much value. Arguably, there's not much reason for that code to be modular at all. For the above reasons, make the cpufreq stats code non-modular, modify the core to invoke functions provided by that code directly and drop the notifiers from it. Make the stats sysfs attributes appear empty if fast frequency switching is enabled as the statistics will not be updated in that case anyway (and returning -EBUSY from those attributes breaks powertop). While at it, clean up Kconfig help for the CPU_FREQ_STAT and CPU_FREQ_STAT_DETAILS options. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-01-23cpufreq: stats: drop unnecessary lockingViresh Kumar
There is no possibility of any race on updating last_index, trans_table or total_trans as these are updated only by cpufreq_stat_notifier_trans() which will be called sequentially. The only place where locking is still relevant is: cpufreq_stats_update(), which updates time_in_state and last_time. This can be called by two thread in parallel, that may result in races. The two threads being: - sysfs read of time_in_state - and frequency transition that calls cpufreq_stat_notifier_trans(). Remove locking from the first case mentioned above. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: don't update stats on false notifiersViresh Kumar
We need to call cpufreq_stats_update() to update 'time_in_state' for the last frequency. This is achieved by calling it from cpufreq_stat_notifier_trans(), which is called after frequency transition. But if we detect that the cpu's frequency haven't really changed and its a false POSTCHANGE notification, we don't really need to update time_in_state. It wouldn't cause any harm in calling cpufreq_stats_update() but we can avoid calling it here and call it when the frequency really changes. The result will be the same but more efficient. Reviewed-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: don't update stats from show_trans_table()Viresh Kumar
cpufreq_stats_update() updates time_in_state and nothing else. It should ideally be updated only in two cases: - User requested for the current value of time_in_state. - We have switched states and so need to update time for the last state. Currently, we are also doing this while user asks for the transition table of frequencies. It wouldn't do any harm, but no good as well. Its useless here. Remove it. Reviewed-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: time_in_state can't be NULL in cpufreq_stats_update()Viresh Kumar
'time_in_state' can't be NULL if 'stats' is valid. These are allocated together and only if time_in_state is allocated successfully, we update policy->stats. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: create sysfs group once we are readyViresh Kumar
Userspace is free to read value of any file from cpufreq/stats directory once they are created. __cpufreq_stats_create_table() is creating the sysfs files first and then allocating resources for them. Though it would be quite difficult to trigger the racy situation here, but for the sake of keeping sensible code lets create sysfs entries only after we are ready to go. This also does some makeup to the routine to make it look better. Reviewed-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: drop 'cpu' field of struct cpufreq_statsViresh Kumar
'cpu' field of struct cpufreq_stats isn't used anymore and so can be dropped. This change makes cpufreq_stats_update_policy_cpu() empty and so that is removed as well. Reviewed-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: rename 'struct cpufreq_stats' objects as 'stats'Viresh Kumar
Currently we name objects of 'struct cpufreq_stats' as 'stat' and 'stats'. Use 'stats' to make it consistent. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: get rid of per-cpu cpufreq_stats_tableViresh Kumar
All CPUs sharing a cpufreq policy share stats too. For this reason, add a stats pointer to struct cpufreq_policy and drop per-CPU variable cpufreq_stats_table used for accessing cpufreq stats so as to reduce code complexity. Reviewed-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: pass 'stat' to cpufreq_stats_update()Viresh Kumar
It is better to pass a struct cpufreq_stats pointer to cpufreq_stats_update() instead of a CPU number, because that's all it needs. Even if we pass a cpu number to cpufreq_stats_update(), it reads the per-cpu variable to get 'stats' out of it. So we are doing these operations unnecessarily: - First getting the cpu number to pass to cpufreq_stats_update(), stat->cpu. - And then getting stats from the cpu, per_cpu(cpufreq_stats_table, cpu). Reviewed-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: don't check for freq table while freeing statsViresh Kumar
While we allocate stats, we do need to check if freq-table is present or not as we need to use it then. But while freeing stats, all we need to know is if stats holds a valid pointer value. There is no use of testing if cpufreq table is present or not. Don't check it. Reviewed-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: initialize 'cur_time' on its definitionViresh Kumar
'cur_time' is defined in the first line and is then assigned a value in the next line. Initialize it while defining it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: remove unused cpufreq_stats_attributeViresh Kumar
It was never used, but is there since the first commit. Remove it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: return -EEXIST when stats are already allocatedViresh Kumar
__cpufreq_stats_create_table() is called from: - cpufreq notifier on creation of a new policy. Stats will always be NULL here. - cpufreq_stats_init() for all CPUs as cpufreq-stats might have been initialized after cpufreq driver. For any policy, 'stats' will be NULL for the first CPU only and will be valid for all other CPUs managed by the same policy. While we return for other CPUs, we don't return the right error value. It's not that we would fail with -EBUSY. But generally, this is what these return values mean: - EBUSY: we are busy right now, try again. And the retry attempt might be immediate. - EEXIST: We already have what you are trying to create and there is no need to create it again, and so no more tries are required. Reviewed-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23cpufreq: stats: Improve module description stringViresh Kumar
The MODULE_DESCRIPTION() string is just too long and then is broken into multiple lines just to make checkpatch happy. Rewrite it to make it more precise. Reviewed-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-30cpufreq: Use cpufreq_for_each_* macros for frequency table iterationStratos Karafotis
The cpufreq core now supports the cpufreq_for_each_entry and cpufreq_for_each_valid_entry macros helpers for iteration over the cpufreq_frequency_table, so use them. It should have no functional changes. Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr> Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-01Merge tag 'pm+acpi-3.15-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael Wysocki: "The majority of this material spent some time in linux-next, some of it even several weeks. There are a few relatively fresh commits in it, but they are mostly fixes and simple cleanups. ACPI took the lead this time, both in terms of the number of commits and the number of modified lines of code, cpufreq follows and there are a few changes in the PM core and in cpuidle too. A new feature that already got some LWN.net's attention is the device PM QoS extension allowing latency tolerance requirements to be propagated from leaf devices to their ancestors with hardware interfaces for specifying latency tolerance. That should help systems with hardware-driven power management to avoid going too far with it in cases when there are latency tolerance constraints. There also are some significant changes in the ACPI core related to the way in which hotplug notifications are handled. They affect PCI hotplug (ACPIPHP) and the ACPI dock station code too. The bottom line is that all those notification now go through the root notify handler and are propagated to the interested subsystems by means of callbacks instead of having to install a notify handler for each device object that we can potentially get hotplug notifications for. In addition to that ACPICA will now advertise "Windows 2013" compatibility for _OSI, because some systems out there don't work correctly if that is not done (some of them don't even boot). On the system suspend side of things, all of the device suspend and resume callbacks, except for ->prepare() and ->complete(), are now going to be executed asynchronously as that turns out to speed up system suspend and resume on some platforms quite significantly and we have a few more optimizations in that area. Apart from that, there are some new device IDs and fixes and cleanups all over. In particular, the system suspend and resume handling by cpufreq should be improved and the cpuidle menu governor should be a bit more robust now. Specifics: - Device PM QoS support for latency tolerance constraints on systems with hardware interfaces allowing such constraints to be specified. That is necessary to prevent hardware-driven power management from becoming overly aggressive on some systems and to prevent power management features leading to excessive latencies from being used in some cases. - Consolidation of the handling of ACPI hotplug notifications for device objects. This causes all device hotplug notifications to go through the root notify handler (that was executed for all of them anyway before) that propagates them to individual subsystems, if necessary, by executing callbacks provided by those subsystems (those callbacks are associated with struct acpi_device objects during device enumeration). As a result, the code in question becomes both smaller in size and more straightforward and all of those changes should not affect users. - ACPICA update, including fixes related to the handling of _PRT in cases when it is broken and the addition of "Windows 2013" to the list of supported "features" for _OSI (which is necessary to support systems that work incorrectly or don't even boot without it). Changes from Bob Moore and Lv Zheng. - Consolidation of ACPI _OST handling from Jiang Liu. - ACPI battery and AC fixes allowing unusual system configurations to be handled by that code from Alexander Mezin. - New device IDs for the ACPI LPSS driver from Chiau Ee Chew. - ACPI fan and thermal optimizations related to system suspend and resume from Aaron Lu. - Cleanups related to ACPI video from Jean Delvare. - Assorted ACPI fixes and cleanups from Al Stone, Hanjun Guo, Lan Tianyu, Paul Bolle, Tomasz Nowicki. - Intel RAPL (Running Average Power Limits) driver cleanups from Jacob Pan. - intel_pstate fixes and cleanups from Dirk Brandewie. - cpufreq fixes related to system suspend/resume handling from Viresh Kumar. - cpufreq core fixes and cleanups from Viresh Kumar, Stratos Karafotis, Saravana Kannan, Rashika Kheria, Joe Perches. - cpufreq drivers updates from Viresh Kumar, Zhuoyu Zhang, Rob Herring. - cpuidle fixes related to the menu governor from Tuukka Tikkanen. - cpuidle fix related to coupled CPUs handling from Paul Burton. - Asynchronous execution of all device suspend and resume callbacks, except for ->prepare and ->complete, during system suspend and resume from Chuansheng Liu. - Delayed resuming of runtime-suspended devices during system suspend for the PCI bus type and ACPI PM domain. - New set of PM helper routines to allow device runtime PM callbacks to be used during system suspend and resume more easily from Ulf Hansson. - Assorted fixes and cleanups in the PM core from Geert Uytterhoeven, Prabhakar Lad, Philipp Zabel, Rashika Kheria, Sebastian Capella. - devfreq fix from Saravana Kannan" * tag 'pm+acpi-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (162 commits) PM / devfreq: Rewrite devfreq_update_status() to fix multiple bugs PM / sleep: Correct whitespace errors in <linux/pm.h> intel_pstate: Set core to min P state during core offline cpufreq: Add stop CPU callback to cpufreq_driver interface cpufreq: Remove unnecessary braces cpufreq: Fix checkpatch errors and warnings cpufreq: powerpc: add cpufreq transition latency for FSL e500mc SoCs MAINTAINERS: Reorder maintainer addresses for PM and ACPI PM / Runtime: Update runtime_idle() documentation for return value meaning video / output: Drop display output class support fujitsu-laptop: Drop unneeded include acer-wmi: Stop selecting VIDEO_OUTPUT_CONTROL ACPI / gpu / drm: Stop selecting VIDEO_OUTPUT_CONTROL ACPI / video: fix ACPI_VIDEO dependencies cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE} cpufreq: Do not allow ->setpolicy drivers to provide ->target cpufreq: arm_big_little: set 'physical_cluster' for each CPU cpufreq: arm_big_little: make vexpress driver depend on bL core driver ACPI / button: Add ACPI Button event via netlink routine ACPI: Remove duplicate definitions of PREFIX ...
2014-03-13cputime: Default implementation of nsecs -> cputime conversionFrederic Weisbecker
The architectures that override cputime_t (s390, ppc) don't provide any version of nsecs_to_cputime(). Indeed this cputime_t implementation by backend only happens when CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y under which the core code doesn't make any use of nsecs_to_cputime(). At least for now. We are going to make a broader use of it so lets provide a default version with a per usecs granularity. It should be good enough for most usecases. Cc: Ingo Molnar <mingo@kernel.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-03-02cpufreq: stats: Refactor common code into __cpufreq_stats_create_table()Saravana Kannan
cpufreq_frequency_get_table() is called from all callers of __cpufreq_stats_create_table(). So, move it inside. Suggested-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Saravana Kannan <skannan@codeaurora.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-02cpufreq: stats: Fix error handling in __cpufreq_stats_create_table()Saravana Kannan
Remove sysfs group if __cpufreq_stats_create_table() fails after creating one. Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Saravana Kannan <skannan@codeaurora.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-02cpufreq: stats: Remove redundant cpufreq_cpu_get() callSaravana Kannan
__cpufreq_stats_create_table always gets pass the valid and real policy struct. So, there's no need to call cpufreq_cpu_get() to get the policy again. Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Saravana Kannan <skannan@codeaurora.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-17cpufreq: stats: create sysfs entries when cpufreq_stats is a moduleViresh Kumar
When cpufreq_stats is compiled in as a module, cpufreq driver would have already been registered. And so the CPUFREQ_CREATE_POLICY notifiers wouldn't be called for it. Hence no sysfs entries for stats. :( This patch calls cpufreq_stats_create_table() for each online CPU from cpufreq_stats_init() and so if policy is already created for CPUx then we will register sysfs stats for it. When its not compiled as module, we will return early as policy wouldn't be found for any of the CPUs. Acked-by: Nicolas Pitre <nico@linaro.org> Tested-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-17cpufreq: stats: free table and remove sysfs entry in a single routineViresh Kumar
We don't have code paths now where we need to do these two things separately, so it is better do them in a single routine. Just as they are allocated in a single routine. Acked-by: Nicolas Pitre <nico@linaro.org> Tested-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-17cpufreq: stats: remove hotplug notifiersViresh Kumar
Either CPUs are hot-unplugged or suspend/resume occurs, cpufreq core will send notifications to cpufreq-stats and stats structure and sysfs entries would be correctly handled.. And so we don't actually need hotcpu notifiers in cpufreq-stats anymore. We were only handling cpu hot-unplug events here and that are already taken care of by POLICY notifiers. Acked-by: Nicolas Pitre <nico@linaro.org> Tested-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-17cpufreq: stats: handle cpufreq_unregister_driver() and suspend/resume properlyViresh Kumar
There are several problems with cpufreq stats in the way it handles cpufreq_unregister_driver() and suspend/resume.. - We must not lose data collected so far when suspend/resume happens and so stats directories must not be removed/allocated during these operations, which is done currently. - cpufreq_stat has registered notifiers with both cpufreq and hotplug. It adds sysfs stats directory with a cpufreq notifier: CPUFREQ_NOTIFY and removes this directory with a notifier from hotplug core. In case cpufreq_unregister_driver() is called (on rmmod cpufreq driver), stats directories per cpu aren't removed as CPUs are still online. The only call cpufreq_stats gets is cpufreq_stats_update_policy_cpu() for all CPUs except the last of each policy. And pointer to stat information is stored in the entry for last CPU in the per-cpu cpufreq_stats_table. But policy structure would be freed inside cpufreq core and so that will result in memory leak inside cpufreq stats (as we are never freeing memory for stats). Now if we again insert the module cpufreq_register_driver() will be called and we will again allocate stats data and put it on for first CPU of every policy. In case we only have a single CPU per policy, we will return with a error from cpufreq_stats_create_table() due to this code: if (per_cpu(cpufreq_stats_table, cpu)) return -EBUSY; And so probably cpufreq stats directory would not show up anymore (as it was added inside last policies->kobj which doesn't exist anymore). I haven't tested it, though. Also the values in stats files wouldn't be refreshed as we are using the earlier stats structure. - CPUFREQ_NOTIFY is called from cpufreq_set_policy() which is called for scenarios where we don't really want cpufreq_stat_notifier_policy() to get called. For example whenever we are changing anything related to a policy: min/max/current freq, etc. cpufreq_set_policy() is called and so cpufreq stats is notified. Where we don't do any useful stuff other than simply returning with -EBUSY from cpufreq_stats_create_table(). And so this isn't the right notifier that cpufreq stats.. Due to all above reasons this patch does following changes: - Add new notifiers CPUFREQ_CREATE_POLICY and CPUFREQ_REMOVE_POLICY, which are only called when policy is created/destroyed. They aren't called for suspend/resume paths.. - Use these notifiers in cpufreq_stat_notifier_policy() to create/destory stats sysfs entries. And so cpufreq_unregister_driver() or suspend/resume shouldn't be a problem for cpufreq_stats. - Return early from cpufreq_stat_cpu_callback() for suspend/resume sequence, so that we don't free stats structure. Acked-by: Nicolas Pitre <nico@linaro.org> Tested-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10cpufreq: Fix wrong time unit conversionAndreas Schwab
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>
2013-08-07cpufreq: 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>
2013-08-07cpufreq: 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: 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>
2013-07-19Merge tag 'pm+acpi-3.11-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management and ACPI fixes from Rafael Wysocki: "These are fixes collected over the last week, most importnatly two cpufreq reverts fixing regressions introduced in 3.10, an autoseelp fix preventing systems using it from crashing during shutdown and two ACPI scan fixes related to hotplug. Specifics: - Two cpufreq commits from the 3.10 cycle introduced regressions. The first of them was buggy (it did way much more than it needed to do) and the second one attempted to fix an issue introduced by the first one. Fixes from Srivatsa S Bhat revert both. - If autosleep triggers during system shutdown and the shutdown callbacks of some device drivers have been called already, it may crash the system. Fix from Liu Shuo prevents that from happening by making try_to_suspend() check system_state. - The ACPI memory hotplug driver doesn't clear its driver_data on errors which may cause a NULL poiter dereference to happen later. Fix from Toshi Kani. - The ACPI namespace scanning code should not try to attach scan handlers to device objects that have them already, which may confuse things quite a bit, and it should rescan the whole namespace branch starting at the given node after receiving a bus check notify event even if the device at that particular node has been discovered already. Fixes from Rafael J Wysocki. - New ACPI video blacklist entry for a system whose initial backlight setting from the BIOS doesn't make sense. From Lan Tianyu. - Garbage string output avoindance for ACPI PNP from Liu Shuo. - Two Kconfig fixes for issues introduced recently in the s3c24xx cpufreq driver (when moving the driver to drivers/cpufreq) from Paul Bolle. - Trivial comment fix in pm_wakeup.h from Chanwoo Choi" * tag 'pm+acpi-3.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI / video: ignore BIOS initial backlight value for Fujitsu E753 PNP / ACPI: avoid garbage in resource name cpufreq: Revert commit 2f7021a8 to fix CPU hotplug regression cpufreq: s3c24xx: fix "depends on ARM_S3C24XX" in Kconfig cpufreq: s3c24xx: rename CONFIG_CPU_FREQ_S3C24XX_DEBUGFS PM / Sleep: Fix comment typo in pm_wakeup.h PM / Sleep: avoid 'autosleep' in shutdown progress cpufreq: Revert commit a66b2e to fix suspend/resume regression ACPI / memhotplug: Fix a stale pointer in error path ACPI / scan: Always call acpi_bus_scan() for bus check notifications ACPI / scan: Do not try to attach scan handlers to devices having them
2013-07-14cpufreq: delete __cpuinit usage from all cpufreq filesPaul Gortmaker
The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. This removes all the drivers/cpufreq uses of the __cpuinit macros from all C files. [1] https://lkml.org/lkml/2013/5/20/589 [v2: leave 2nd lines of args misaligned as requested by Viresh] Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: cpufreq@vger.kernel.org Cc: linux-pm@vger.kernel.org Acked-by: Dirk Brandewie <dirk.j.brandewie@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-15cpufreq: Revert commit a66b2e to fix suspend/resume regressionSrivatsa S. Bhat
commit a66b2e (cpufreq: Preserve sysfs files across suspend/resume) has unfortunately caused several things in the cpufreq subsystem to break subtly after a suspend/resume cycle. The intention of that patch was to retain the file permissions of the cpufreq related sysfs files across suspend/resume. To achieve that, the commit completely removed the calls to cpufreq_add_dev() and __cpufreq_remove_dev() during suspend/resume transitions. But the problem is that those functions do 2 kinds of things: 1. Low-level initialization/tear-down that are critical to the correct functioning of cpufreq-core. 2. Kobject and sysfs related initialization/teardown. Ideally we should have reorganized the code to cleanly separate these two responsibilities, and skipped only the sysfs related parts during suspend/resume. Since we skipped the entire callbacks instead (which also included some CPU and cpufreq-specific critical components), cpufreq subsystem started behaving erratically after suspend/resume. So revert the commit to fix the regression. We'll revisit and address the original goal of that commit separately, since it involves quite a bit of careful code reorganization and appears to be non-trivial. (While reverting the commit, note that another commit f51e1eb (cpufreq: Fix cpufreq regression after suspend/resume) already reverted part of the original set of changes. So revert only the remaining ones). Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Paul Bolle <pebolle@tiscali.nl> Cc: 3.10+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-01cpufreq: Fix cpufreq regression after suspend/resumeSrivatsa S. Bhat
Toralf Förster reported that the cpufreq ondemand governor behaves erratically (doesn't scale well) after a suspend/resume cycle. The problem was that the cpufreq subsystem's idea of the cpu frequencies differed from the actual frequencies set in the hardware after a suspend/resume cycle. Toralf bisected the problem to commit a66b2e5 (cpufreq: Preserve sysfs files across suspend/resume). Among other (harmless) things, that commit skipped the call to cpufreq_update_policy() in the resume path. But cpufreq_update_policy() plays an important role during resume, because it is responsible for checking if the BIOS changed the cpu frequencies behind our back and resynchronize the cpufreq subsystem's knowledge of the cpu frequencies, and update them accordingly. So, restore the call to cpufreq_update_policy() in the resume path to fix the cpufreq regression. Reported-and-tested-by: Toralf Förster <toralf.foerster@gmx.de> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: 3.10+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-21cpufreq: Fix minor formatting issuesViresh Kumar
There were a few noticeable formatting issues in core cpufreq code. This cleans them up to make code look better. The changes include: - Whitespace cleanup. - Rearrangements of code. - Multiline comments fixes. - Formatting changes to fit 80 columns. Copyright information in cpufreq.c is also updated to include my name for 2013. [rjw: Changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-15cpufreq: Preserve sysfs files across suspend/resumeSrivatsa S. Bhat
The file permissions of cpufreq per-cpu sysfs files are not preserved across suspend/resume because we internally go through the CPU Hotplug path which reinitializes the file permissions on CPU online. But the user is not supposed to know that we are using CPU hotplug internally within suspend/resume (IOW, the kernel should not silently wreck the user-set file permissions across a suspend cycle). Therefore, we need to preserve the file permissions as they are across suspend/resume. The simplest way to achieve that is to just not touch the sysfs files at all - ie., just ignore the CPU hotplug notifications in the suspend/resume path (_FROZEN) in the cpufreq hotplug callback. Reported-by: Robert Jarzmik <robert.jarzmik@intel.com> Reported-by: Durgadoss R <durgadoss.r@intel.com> 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>
2013-03-25cpufreq: stats: do cpufreq_cpu_put() corresponding to cpufreq_cpu_get()viresh kumar
In cpufreq_stats_free_sysfs() we aren't balancing calls to cpufreq_cpu_get() with cpufreq_cpu_put(). This will never let us have ref count to policy->kobj as zero. We will get a hang if somehow cpufreq_driver_unregister() is called. And that can happen when we compile our driver as module and insmod/rmmod it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Amit Kucheria <amit.kucheria@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09cpufreq_stats: do not remove sysfs files if frequency table is not presentDirk Brandewie
The sysfs files for cpufreq_stats are created in cpufreq_stats_create_table() called from cpufreq_stat_notifier_policy() when a policy is added to the cpu. cpufreq_stats_create_table() will not be called if the scaling driver does not export a frequency table to cpufreq. Use the same fence on tear down. Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09cpufreq / stats: Get rid of CPUFREQ_STATDEVICE_ATTRViresh Kumar
Macro "CPUFREQ_STATDEVICE_ATTR" is defined local to cpufreq_stats.c file and is almost a copy of the generic version present in cpufreq.h file. Lets use the generic version instead. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02cpufreq: governors: implement generic policy_is_sharedFabio Baltieri
Implement a generic helper function policy_is_shared() to replace the current dbs_sw_coordinated_cpus() at cpufreq level, so that it can be used by code other than cpufreq governors. Suggested-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Fabio Baltieri <fabio.baltieri@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02cpufreq: Simplify __cpufreq_remove_dev()Viresh Kumar
__cpufreq_remove_dev() is called on multiple occasions: cpufreq_driver unregister and cpu removals. Current implementation of this routine is overly complex without much need. If the cpu to be removed is the policy->cpu, we remove the policy first and add all other cpus again from policy->cpus and then finally call __cpufreq_remove_dev() again to remove the cpu to be deleted. Haahhhh.. There exist a simple solution to removal of a cpu: - Simply use the old policy structure - update its fields like: policy->cpu, etc. - notify any users of cpufreq, which depend on changing policy->cpu Hence this patch, which tries to implement the above theory. It is tested well by myself on ARM big.LITTLE TC2 SoC, which has 5 cores (2 A15 and 3 A7). Both A15's share same struct policy and all A7's share same policy structure. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-03cpufreq / stats: fix race between stats allocation and first usageKonstantin Khlebnikov
This patch forces complete struct cpufreq_stats allocation for all cpus before registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some conditions cpufreq_stat_notifier_trans() can be called in the middle of stats allocation, in this case cpufreq_stats_table already exists, but stat->freq_table is NULL. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15cpufreq: Fix sparse warnings by updating cputime64_t to u64Viresh Kumar
There were few sparse warnings due to mismatch of type on function arguments. Two types were used u64 and cputime64_t. Both are actually u64, so use u64 only. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-10-23Fix memory leak in cpufreq stats.Tu, Xiaobing
When system enters sleep, non-boot CPUs will be disabled. Cpufreq stats sysfs is created when the CPU is up, but it is not freed when the CPU is going down. This will cause memory leak. Signed-off-by: xiaobing tu <xiaobing.tu@intel.com> Signed-off-by: guifang tang <guifang.tang@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-01-07Merge branch 'driver-core-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core * 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (73 commits) arm: fix up some samsung merge sysdev conversion problems firmware: Fix an oops on reading fw_priv->fw in sysfs loading file Drivers:hv: Fix a bug in vmbus_driver_unregister() driver core: remove __must_check from device_create_file debugfs: add missing #ifdef HAS_IOMEM arm: time.h: remove device.h #include driver-core: remove sysdev.h usage. clockevents: remove sysdev.h arm: convert sysdev_class to a regular subsystem arm: leds: convert sysdev_class to a regular subsystem kobject: remove kset_find_obj_hinted() m86k: gpio - convert sysdev_class to a regular subsystem mips: txx9_sram - convert sysdev_class to a regular subsystem mips: 7segled - convert sysdev_class to a regular subsystem sh: dma - convert sysdev_class to a regular subsystem sh: intc - convert sysdev_class to a regular subsystem power: suspend - convert sysdev_class to a regular subsystem power: qe_ic - convert sysdev_class to a regular subsystem power: cmm - convert sysdev_class to a regular subsystem s390: time - convert sysdev_class to a regular subsystem ... Fix up conflicts with 'struct sysdev' removal from various platform drivers that got changed: - arch/arm/mach-exynos/cpu.c - arch/arm/mach-exynos/irq-eint.c - arch/arm/mach-s3c64xx/common.c - arch/arm/mach-s3c64xx/cpu.c - arch/arm/mach-s5p64x0/cpu.c - arch/arm/mach-s5pv210/common.c - arch/arm/plat-samsung/include/plat/cpu.h - arch/powerpc/kernel/sysfs.c and fix up cpu_is_hotpluggable() as per Greg in include/linux/cpu.h
2011-12-21cpu: convert 'cpu' and 'machinecheck' sysdev_class to a regular subsystemKay Sievers
This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem and converts the devices to regular devices. The sysdev drivers are implemented as subsystem interfaces now. After all sysdev classes are ported to regular driver core entities, the sysdev implementation will be entirely removed from the kernel. Userspace relies on events and generic sysfs subsystem infrastructure from sysdev devices, which are made available with this conversion. Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Borislav Petkov <bp@amd64.org> Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk> Cc: Len Brown <lenb@kernel.org> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Dave Jones <davej@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-12-15[S390] cputime: add sparse checking and cleanupMartin Schwidefsky
Make cputime_t and cputime64_t nocast to enable sparse checking to detect incorrect use of cputime. Drop the cputime macros for simple scalar operations. The conversion macros are still needed. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>