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* cpufreq: governor: Serialize governor callbacksViresh Kumar2015-06-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are several races reported in cpufreq core around governors (only ondemand and conservative) by different people. There are at least two race scenarios present in governor code: (a) Concurrent access/updates of governor internal structures. It is possible that fields such as 'dbs_data->usage_count', etc. are accessed simultaneously for different policies using same governor structure (i.e. CPUFREQ_HAVE_GOVERNOR_PER_POLICY flag unset). And because of this we can dereference bad pointers. For example consider a system with two CPUs with separate 'struct cpufreq_policy' instances. CPU0 governor: ondemand and CPU1: powersave. CPU0 switching to powersave and CPU1 to ondemand: CPU0 CPU1 store* store* cpufreq_governor_exit() cpufreq_governor_init() dbs_data = cdata->gdbs_data; if (!--dbs_data->usage_count) kfree(dbs_data); dbs_data->usage_count++; *Bad pointer dereference* There are other races possible between EXIT and START/STOP/LIMIT as well. Its really complicated. (b) Switching governor state in bad sequence: For example trying to switch a governor to START state, when the governor is in EXIT state. There are some checks present in __cpufreq_governor() but they aren't sufficient as they compare events against 'policy->governor_enabled', where as we need to take governor's state into account, which can be used by multiple policies. These two issues need to be solved separately and the responsibility should be properly divided between cpufreq and governor core. The first problem is more about the governor core, as it needs to protect its structures properly. And the second problem should be fixed in cpufreq core instead of governor, as its all about sequence of events. This patch is trying to solve only the first problem. There are two types of data we need to protect, - 'struct common_dbs_data': No matter what, there is going to be a single copy of this per governor. - 'struct dbs_data': With CPUFREQ_HAVE_GOVERNOR_PER_POLICY flag set, we will have per-policy copy of this data, otherwise a single copy. Because of such complexities, the mutex present in 'struct dbs_data' is insufficient to solve our problem. For example we need to protect fetching of 'dbs_data' from different structures at the beginning of cpufreq_governor_dbs(), to make sure it isn't currently being updated. This can be fixed if we can guarantee serialization of event parsing code for an individual governor. This is best solved with a mutex per governor, and the placeholder for that is 'struct common_dbs_data'. And so this patch moves the mutex from 'struct dbs_data' to 'struct common_dbs_data' and takes it at the beginning and drops it at the end of cpufreq_governor_dbs(). Tested with and without following configuration options: CONFIG_LOCKDEP_SUPPORT=y CONFIG_DEBUG_RT_MUTEXES=y CONFIG_DEBUG_PI_LIST=y CONFIG_DEBUG_SPINLOCK=y CONFIG_DEBUG_MUTEXES=y CONFIG_DEBUG_LOCK_ALLOC=y CONFIG_PROVE_LOCKING=y CONFIG_LOCKDEP=y CONFIG_DEBUG_ATOMIC_SLEEP=y Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: governor: register notifier from cs_init()Viresh Kumar2015-06-151-11/+15
| | | | | | | | | | Notifiers are required only for conservative governor and the common governor code is unnecessarily polluted with that. Handle that from cs_init/exit() instead of cpufreq_governor_dbs(). Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: conservative: set requested_freq to policy max when it is over ↵Xiaoguang Chen2013-11-121-0/+3
| | | | | | | | | | | policy max When requested_freq is over policy->max, set it to policy->max. This can help to speed up decreasing frequency. Signed-off-by: Xiaoguang Chen <chenxg@marvell.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: conservative: fix requested_freq reduction issueXiaoguang Chen2013-11-071-1/+6
| | | | | | | | | | | | | | | When decreasing frequency, requested_freq may be less than freq_target, So requested_freq minus freq_target may be negative, But reqested_freq's unit is unsigned int, then the negative result will be one larger interger which may be even higher than requested_freq. This patch is to fix such issue. when result becomes negative, set requested_freq as the min value of policy. Signed-off-by: Xiaoguang Chen <chenxg@marvell.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: governors: Remove duplicate check of target freq in supported rangeStratos Karafotis2013-08-281-4/+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>
* Merge back earlier 'pm-cpufreq' materialRafael J. Wysocki2013-08-141-13/+1
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| * cpufreq: Use sizeof(*ptr) convetion for computing sizesViresh Kumar2013-08-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * cpufreq: Clean up header files included in the coreViresh Kumar2013-08-071-12/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | cpufreq: rename ignore_nice as ignore_nice_loadViresh Kumar2013-08-071-10/+10
|/ | | | | | | | | | | | | 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>
* cpufreq: conservative: Use an inline function to evaluate freq_targetStratos Karafotis2013-04-011-12/+16
| | | | | | | | | | Use an inline function to evaluate freq_target to avoid duplicate code. Also, define a macro for the default frequency step. 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>
* cpufreq: conservative: Fix the logic in frequency decrease checkingStratos Karafotis2013-04-011-6/+2
| | | | | | | | | | | | | When we evaluate the CPU load for frequency decrease we have to compare the load against down_threshold. There is no need to subtract 10 points from down_threshold. Instead, we have to use the default down_threshold or user's selection unmodified. 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>
* cpufreq: conservative: Fix sampling_down_factor functionalityStratos Karafotis2013-04-011-3/+8
| | | | | | | | | | | | sampling_down_factor tunable is unused since commit 8e677ce83bf41ba9c74e5b6d9ee60b07d4e5ed93 (4 years ago). This patch restores the original functionality and documents the tunable. 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>
* cpufreq: governors: Calculate iowait time only when necessaryStratos Karafotis2013-04-011-1/+1
| | | | | | | | | | | | | | | Currently we always calculate the CPU iowait time and add it to idle time. If we are in ondemand and we use io_is_busy, we re-calculate iowait time and we subtract it from idle time. With this patch iowait time is calculated only when necessary avoiding the double call to get_cpu_iowait_time_us. We use a parameter in function get_cpu_idle_time to distinguish when the iowait time will be added to idle time or not, without the need of keeping the prev_io_wait. 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>
* cpufreq: conservative: Fix relation when decreasing frequencyNamhyung Kim2013-04-011-1/+1
| | | | | | | | | The relation should be CPUFREQ_RELATION_L to find optimal frequency when decreasing. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: conservative: Break out earlier on the lowest frequencyNamhyung Kim2013-04-011-6/+6
| | | | | | | | | If we're on the lowest frequency, no need to calculate new freq. Break out even earlier in this case. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: governors: Avoid unnecessary per cpu timer interruptsViresh Kumar2013-04-011-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | Following patch has introduced per cpu timers or works for ondemand and conservative governors. commit 2abfa876f1117b0ab45f191fb1f82c41b1cbc8fe Author: Rickard Andersson <rickard.andersson@stericsson.com> Date: Thu Dec 27 14:55:38 2012 +0000 cpufreq: handle SW coordinated CPUs This causes additional unnecessary interrupts on all cpus when the load is recently evaluated by any other cpu. i.e. When load is recently evaluated by cpu x, we don't really need any other cpu to evaluate this load again for the next sampling_rate time. Some sort of code is present to avoid that but we are still getting timer interrupts for all cpus. A good way of avoiding this would be to modify delays for all cpus (policy->cpus) whenever any cpu has evaluated load. This patch does this change and some related code cleanup. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: governor: Implement per policy instances of governorsViresh Kumar2013-04-011-75/+118
| | | | | | | | | | | | | | | | | | | | | | Currently, there can't be multiple instances of single governor_type. If we have a multi-package system, where we have multiple instances of struct policy (per package), we can't have multiple instances of same governor. i.e. We can't have multiple instances of ondemand governor for multiple packages. Governors directory in sysfs is created at /sys/devices/system/cpu/cpufreq/ governor-name/. Which again reflects that there can be only one instance of a governor_type in the system. This is a bottleneck for multicluster system, where we want different packages to use same governor type, but with different tunables. This patch uses the infrastructure provided by earlier patch and implements init/exit routines for ondemand and conservative governors. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: conservative: Fix typos in commentsStratos Karafotis2013-02-091-2/+2
| | | | | | | | Fix a couple of typos in comments. 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>
* cpufreq: governors: Remove code redundancy between governorsViresh Kumar2013-02-021-43/+9
| | | | | | | | | | | | | | | With the inclusion of following patches: 9f4eb10 cpufreq: conservative: call dbs_check_cpu only when necessary 772b4b1 cpufreq: ondemand: call dbs_check_cpu only when necessary code redundancy between the conservative and ondemand governors is introduced again, so get rid of it. [rjw: Changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Fabio Baltieri <fabio.baltieri@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: governors: fix misuse of cdbs.cpuFabio Baltieri2013-02-021-2/+3
| | | | | | | | | | | Fix governors code to set all cpu's cdbs->cpu to the the actual cpu id and use cur_policy->cpu istead of cdbs->cpu to track current governor's leader cpu. Reported-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>
* cpufreq: governors: implement generic policy_is_sharedFabio Baltieri2013-02-021-1/+1
| | | | | | | | | | | 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>
* cpufreq: conservative: call dbs_check_cpu only when necessaryFabio Baltieri2013-02-021-6/+41
| | | | | | | | Modify conservative timer to not resample CPU utilization if recently sampled from another SW coordinated core. Signed-off-by: Fabio Baltieri <fabio.baltieri@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: handle SW coordinated CPUsRickard Andersson2013-02-021-1/+2
| | | | | | | | | | | | | | | This patch fixes a bug that occurred when we had load on a secondary CPU and the primary CPU was sleeping. Only one sampling timer was spawned and it was spawned as a deferred timer on the primary CPU, so when a secondary CPU had a change in load this was not detected by the cpufreq governor (both ondemand and conservative). This patch make sure that deferred timers are run on all CPUs in the case of software controlled CPUs that run on the same frequency. Signed-off-by: Rickard Andersson <rickard.andersson@stericsson.com> Signed-off-by: Fabio Baltieri <fabio.baltieri@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: governors: remove redundant codeViresh Kumar2012-11-151-389/+159
| | | | | | | | | | | | | | | Initially ondemand governor was written and then using its code conservative governor is written. It used a lot of code from ondemand governor, but copy of code was created instead of using the same routines from both governors. Which increased code redundancy, which is difficult to manage. This patch is an attempt to move common part of both the governors to cpufreq_governor.c file to come over above mentioned issues. This shouldn't change anything from functionality point of view. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Move common part from governors to separate file, v2viresh kumar2012-11-151-34/+0
| | | | | | | | | | | | Multiple cpufreq governers have defined similar get_cpu_idle_time_***() routines. These routines must be moved to some common place, so that all governors can use them. So moving them to cpufreq_governor.c, which seems to be a better place for keeping these routines. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Merge tag 'pm-for-3.7-rc1' of ↵Linus Torvalds2012-10-031-0/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael J Wysocki: - Improved system suspend/resume and runtime PM handling for the SH TMU, CMT and MTU2 clock event devices (also used by ARM/shmobile). - Generic PM domains framework extensions related to cpuidle support and domain objects lookup using names. - ARM/shmobile power management updates including improved support for the SH7372's A4S power domain containing the CPU core. - cpufreq changes related to AMD CPUs support from Matthew Garrett, Andre Przywara and Borislav Petkov. - cpu0 cpufreq driver from Shawn Guo. - cpufreq governor fixes related to the relaxing of limit from Michal Pecio. - OMAP cpufreq updates from Axel Lin and Richard Zhao. - cpuidle ladder governor fixes related to the disabling of states from Carsten Emde and me. - Runtime PM core updates related to the interactions with the system suspend core from Alan Stern and Kevin Hilman. - Wakeup sources modification allowing more helper functions to be called from interrupt context from John Stultz and additional diagnostic code from Todd Poynor. - System suspend error code path fix from Feng Hong. Fixed up conflicts in cpufreq/powernow-k8 that stemmed from the workqueue fixes conflicting fairly badly with the removal of support for hardware P-state chips. The changes were independent but somewhat intertwined. * tag 'pm-for-3.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits) Revert "PM QoS: Use spinlock in the per-device PM QoS constraints code" PM / Runtime: let rpm_resume() succeed if RPM_ACTIVE, even when disabled, v2 cpuidle: rename function name "__cpuidle_register_driver", v2 cpufreq: OMAP: Check IS_ERR() instead of NULL for omap_device_get_by_hwmod_name cpuidle: remove some empty lines PM: Prevent runtime suspend during system resume PM QoS: Use spinlock in the per-device PM QoS constraints code PM / Sleep: use resume event when call dpm_resume_early cpuidle / ACPI : move cpuidle_device field out of the acpi_processor_power structure ACPI / processor: remove pointless variable initialization ACPI / processor: remove unused function parameter cpufreq: OMAP: remove loops_per_jiffy recalculate for smp sections: fix section conflicts in drivers/cpufreq cpufreq: conservative: update frequency when limits are relaxed cpufreq / ondemand: update frequency when limits are relaxed properly __init-annotate pm_sysrq_init() cpufreq: Add a generic cpufreq-cpu0 driver PM / OPP: Initialize OPP table from device tree ARM: add cpufreq transiton notifier to adjust loops_per_jiffy for smp cpufreq: Remove support for hardware P-state chips from powernow-k8 ...
| * cpufreq: conservative: update frequency when limits are relaxedMichal Pecio2012-09-141-0/+1
| | | | | | | | | | | | | | | | | | | | Reevaluate CPU load and update frequency immediately whenever limits are changed. Currently conservative doesn't do that when limits are relaxed, wasting power on systems with relatively low sampling rate. Signed-off-by: Michal Pecio <mpecio@nvidia.com> Reviewed-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
| * PM / cpufreq: Initialise the cpu field during conservative governor startAmit Daniel Kachhap2012-09-041-0/+1
| | | | | | | | | | | | | | | | | | This change initialises the cpu id field of cs_cpu_dbs_info structure in conservative governor and keep this consistent with other governors. Similar initialisation is present in ondemand governor. Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* | workqueue: make deferrable delayed_work initializer names consistentTejun Heo2012-08-211-1/+1
|/ | | | | | | | | | | | | | | | | | Initalizers for deferrable delayed_work are confused. * __DEFERRED_WORK_INITIALIZER() * DECLARE_DEFERRED_WORK() * INIT_DELAYED_WORK_DEFERRABLE() Rename them to * __DEFERRABLE_WORK_INITIALIZER() * DECLARE_DEFERRABLE_WORK() * INIT_DEFERRABLE_WORK() This patch doesn't cause any functional changes. Signed-off-by: Tejun Heo <tj@kernel.org>
* Merge branch 'sched/core' of ↵Martin Schwidefsky2011-12-191-21/+20
|\ | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into cputime-tip Conflicts: drivers/cpufreq/cpufreq_conservative.c drivers/cpufreq/cpufreq_ondemand.c drivers/macintosh/rack-meter.c fs/proc/stat.c fs/proc/uptime.c kernel/sched/core.c
| * sched/accounting: Change cpustat fields to an arrayGlauber Costa2011-12-061-20/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch changes fields in cpustat from a structure, to an u64 array. Math gets easier, and the code is more flexible. Signed-off-by: Glauber Costa <glommer@parallels.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Paul Tuner <pjt@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1322498719-2255-2-git-send-email-glommer@parallels.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | [S390] cputime: add sparse checking and cleanupMartin Schwidefsky2011-12-151-15/+14
|/ | | | | | | | 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>
* nohz: Fix update_ts_time_stat idle accountingMichal Hocko2011-09-081-1/+3
| | | | | | | | | | | | | | | | | | | | | update_ts_time_stat currently updates idle time even if we are in iowait loop at the moment. The only real users of the idle counter (via get_cpu_idle_time_us) are CPU governors and they expect to get cumulative time for both idle and iowait times. The value (idle_sleeptime) is also printed to userspace by print_cpu but it prints both idle and iowait times so the idle part is misleading. Let's clean this up and fix update_ts_time_stat to account both counters properly and update consumers of idle to consider iowait time as well. If we do this we might use get_cpu_{idle,iowait}_time_us from other contexts as well and we will get expected values. Signed-off-by: Michal Hocko <mhocko@suse.cz> Cc: Dave Jones <davej@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Alexey Dobriyan <adobriyan@gmail.com> Link: http://lkml.kernel.org/r/e9c909c221a8da402c4da07e4cd968c3218f8eb1.1314172057.git.mhocko@suse.cz Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* [CPUFREQ] Remove unneeded locksThomas Renninger2011-03-161-29/+5
| | | | | | | | | | | | | There cannot be any concurrent access to these through different cpu sysfs files anymore, because these tunables are now all global (not per cpu). I still have some doubts whether some of these locks were needed at all. Anyway, let's get rid of them. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com> CC: cpufreq@vger.kernel.org
* [CPUFREQ] Remove old, deprecated per cpu ondemand/conservative sysfs filesThomas Renninger2011-03-161-74/+0
| | | | | | | | Marked deprecated for quite a whilte now... Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com> CC: cpufreq@vger.kernel.org
* [CPUFREQ] Remove deprecated sysfs file sampling_rate_maxThomas Renninger2011-03-161-13/+0
| | | | | | | | Marked deprecated for quite a while now... Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com> CC: cpufreq@vger.kernel.org
* [CPUFREQ] drivers/cpufreq: Remove unnecessary semicolonsJoe Perches2011-03-161-1/+1
| | | | | Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Dave Jones <davej@redhat.com>
* cpufreq: use system_wq instead of dedicated workqueuesTejun Heo2011-01-261-19/+3
| | | | | | | | | | | | With cmwq, there's no reason for cpufreq drivers to use separate workqueues. Remove the dedicated workqueues from cpufreq_conservative and cpufreq_ondemand and use system_wq instead. The work items are already sync canceled on stop, so it's already guaranteed that no work is running on module exit. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Dave Jones <davej@redhat.com> Cc: cpufreq@vger.kernel.org
* Merge commit 'v2.6.34-rc6' into x86/cpuH. Peter Anvin2010-05-081-2/+6
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| * [CPUFREQ] use max load in conservative governorDominik Brodowski2010-03-311-2/+6
| | | | | | | | | | | | | | | | | | Instead of using the load of the last CPU in a package, use the maximum load of all CPUs in a package. Reported-by: Jean-Christian Goussard <jeanchristian.goussard@sfr.fr> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Dave Jones <davej@redhat.com>
* | cpufreq: Unify sysfs attribute definition macrosBorislav Petkov2010-04-091-32/+16
|/ | | | | | | | | | | Multiple modules used to define those which are with identical functionality and were needlessly replicated among the different cpufreq drivers. Push them into the header and remove duplication. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> LKML-Reference: <1270065406-1814-7-git-send-email-bp@amd64.org> Reviewed-by: Thomas Renninger <trenn@suse.de> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* [CPUFREQ] Use global sysfs cpufreq structure for conservative governor tuningsThomas Renninger2009-11-241-19/+110
| | | | | | | Same adustments that have been added to the ondemand recently. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] Resolve time unit thinko in ondemand/conservative govsPallipadi, Venkatesh2009-11-181-2/+2
| | | | | | | | | | | | | | | | | ondemand and conservative governors are messing up time units in the code path where NO_HZ is not enabled and ignore_nice is set. The walltime idletime stored is in jiffies and nice time calculation is happening in microseconds. The problem was reported and diagnosed by Alexander here. http://marc.info/?l=linux-kernel&m=125752550404513&w=2 The patch below fixes this thinko. Reported-by: Alexander Miller <Miller@fmi.uni-stuttgart.de> Tested-by: Alexander Miller <Miller@fmi.uni-stuttgart.de> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
* Merge branch 'percpu-for-linus' into percpu-for-nextTejun Heo2009-08-141-25/+18
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/sparc/kernel/smp_64.c arch/x86/kernel/cpu/perf_counter.c arch/x86/kernel/setup_percpu.c drivers/cpufreq/cpufreq_ondemand.c mm/percpu.c Conflicts in core and arch percpu codes are mostly from commit ed78e1e078dd44249f88b1dd8c76dafb39567161 which substituted many num_possible_cpus() with nr_cpu_ids. As for-next branch has moved all the first chunk allocators into mm/percpu.c, the changes are moved from arch code to mm/percpu.c. Signed-off-by: Tejun Heo <tj@kernel.org>
| * [CPUFREQ] Fix NULL pointer dereference regression in conservative governorPallipadi, Venkatesh2009-08-041-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit ee88415caf736b89500f16e0a545614541a45005 introduced this regression when it removed enable bit in cpu_dbs_info_s. That added a possibility of dbs_cpufreq_notifier getting called for a CPU that is not yet managed by conservative governor. That will happen as the transition notifier is set as soon as one CPU switches to conservative governor and other CPUs can get a NULL pointer dereference without the enable bit check. Add the enable bit back again. Reported-by: Lermytte Christophe <Christophe.Lermytte@thomson.net> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
| * [CPUFREQ] Cleanup locking in conservative governorvenkatesh.pallipadi@intel.com2009-07-071-21/+13
| | | | | | | | | | | | | | | | | | Redesign the locking inside conservative driver. Make dbs_mutex handle all the global state changes inside the driver and invent a new percpu mutex to serialize percpu timer and frequency limit change. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
| * [CPUFREQ] Eliminate the recent lockdep warnings in cpufreqvenkatesh.pallipadi@intel.com2009-07-071-16/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit b14893a62c73af0eca414cfed505b8c09efc613c although it was very much needed to properly cleanup ondemand timer, opened-up a can of worms related to locking dependencies in cpufreq. Patch here defines the need for dbs_mutex and cleans up its usage in ondemand governor. This also resolves the lockdep warnings reported here http://lkml.indiana.edu/hypermail/linux/kernel/0906.1/01925.html http://lkml.indiana.edu/hypermail/linux/kernel/0907.0/00820.html and few others.. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
* | percpu: clean up percpu variable definitionsTejun Heo2009-06-241-6/+6
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Percpu variable definition is about to be updated such that all percpu symbols including the static ones must be unique. Update percpu variable definitions accordingly. * as,cfq: rename ioc_count uniquely * cpufreq: rename cpu_dbs_info uniquely * xen: move nesting_count out of xen_evtchn_do_upcall() and rename it * mm: move ratelimits out of balance_dirty_pages_ratelimited_nr() and rename it * ipv4,6: rename cookie_scratch uniquely * x86 perf_counter: rename prev_left to pmc_prev_left, irq_entry to pmc_irq_entry and nmi_entry to pmc_nmi_entry * perf_counter: rename disable_count to perf_disable_count * ftrace: rename test_event_disable to ftrace_test_event_disable * kmemleak: rename test_pointer to kmemleak_test_pointer * mce: rename next_interval to mce_next_interval [ Impact: percpu usage cleanups, no duplicate static percpu var names ] Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Dave Jones <davej@redhat.com> Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: linux-mm <linux-mm@kvack.org> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <srostedt@redhat.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andi Kleen <andi@firstfloor.org>
* [CPUFREQ] Only set sampling_rate_max deprecated, sampling_rate_min is usefulThomas Renninger2009-06-151-15/+2
| | | | | | | | Update the documentation accordingly. Cleanup and use printk_once. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] ondemand: Uncouple minimal sampling rate from HZ in NO_HZ caseThomas Renninger2009-06-151-26/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | With this patch you have following minimal sampling rate restrictions: Kernel restrictions: If CONFIG_NO_HZ is set, the limit is 10ms fixed. If CONFIG_NO_HZ is not set or no_hz=off boot parameter is used, the limits depend on the CONFIG_HZ option: HZ=1000: min=20000us (20ms) HZ=250: min=80000us (80ms) HZ=100: min=200000us (200ms) HW restrictions: Do not sample/poll more often than HW latency * 100 exported by the low level cpufreq HW driver The higher value of above restrictions is the minimal sampling rate that can be set (and can be seen via ondemand/sampling_rate_min sysfs file) Default sampling rate still is HW latency * 1000, but this will now end up in lower values on latest (Intel and AMD) hardware as these can switch really fast and sampling rate mostly was limited to the 80ms or 200ms (depending on whether HZ=250 or HZ=1000 is used). Signed-off-by: Thomas Renninger <trenn@suse.de> Cc: Pallipadi Venkatesh <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
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