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* cpufreq: Fix typo in kerneldoc commentYue Hu2021-02-191-1/+1
| | | | | | | | | | | Change 'Terget' to 'Target'. Should be Target. Signed-off-by: Yue Hu <huyue2@yulong.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Subject edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Remove CPUFREQ_STICKY flagViresh Kumar2021-02-041-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During cpufreq driver's registration, if the ->init() callback for all the CPUs fail then there is not much point in keeping the driver around as it will only account for more of unnecessary noise, for example cpufreq core will try to suspend/resume the driver which never got registered properly. The removal of such a driver is avoided if the driver carries the CPUFREQ_STICKY flag. This was added way back [1] in 2004 and perhaps no one should ever need it now. A lot of drivers do set this flag, probably because they just copied it from other drivers. This was added earlier for some platforms [2] because their cpufreq drivers were getting registered before the CPUs were registered with subsys framework. And hence they used to fail. The same isn't true anymore though. The current code flow in the kernel is: start_kernel() -> kernel_init() -> kernel_init_freeable() -> do_basic_setup() -> driver_init() -> cpu_dev_init() -> subsys_system_register() //For CPUs -> do_initcalls() -> cpufreq_register_driver() Clearly, the CPUs will always get registered with subsys framework before any cpufreq driver can get probed. Remove the flag and update the relevant drivers. Link: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/include/linux/cpufreq.h?id=7cc9f0d9a1ab04cedc60d64fd8dcf7df224a3b4d # [1] Link: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/arch/arm/mach-sa1100/cpu-sa1100.c?id=f59d3bbe35f6268d729f51be82af8325d62f20f5 # [2] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Add special-purpose fast-switching callback for driversRafael J. Wysocki2020-12-151-0/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | First off, some cpufreq drivers (eg. intel_pstate) can pass hints beyond the current target frequency to the hardware and there are no provisions for doing that in the cpufreq framework. In particular, today the driver has to assume that it should not allow the frequency to fall below the one requested by the governor (or the required capacity may not be provided) which may not be the case and which may lead to excessive energy usage in some scenarios. Second, the hints passed by these drivers to the hardware need not be in terms of the frequency, so representing the utilization numbers coming from the scheduler as frequency before passing them to those drivers is not really useful. Address the two points above by adding a special-purpose replacement for the ->fast_switch callback, called ->adjust_perf, allowing the governor to pass abstract performance level (rather than frequency) values for the minimum (required) and target (desired) performance along with the CPU capacity to compare them to. Also update the schedutil governor to use the new callback instead of ->fast_switch if present and if the utilization mertics are frequency-invariant (that is requisite for the direct mapping between the utilization and the CPU performance levels to be a reasonable approximation). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* cpufreq: Fix cpufreq_online() return value on errorsWang ShaoBo2020-12-111-1/+4
| | | | | | | | | Make cpufreq_online() return negative error codes on all errors that cause the policy to be destroyed, as appropriate. Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com> [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Fix up several kerneldoc commentsRafael J. Wysocki2020-12-111-35/+35
| | | | | | | | | | Fix up the remaining kerneldoc comments that don't adhere to the expected format and clarify some of them a bit. No functional changes. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* Merge back cpufreq updates for v5.11.Rafael J. Wysocki2020-11-161-5/+5
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| * cpufreq: Drop restore_freq from struct cpufreq_policyRafael J. Wysocki2020-11-021-5/+5
| | | | | | | | | | | | | | | | | | | | The restore_freq field in struct cpufreq_policy is only used by __target_index() in one place and a local variable in that function may as well be used instead of it, so drop it and modify __target_index() accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* | cpufreq: Add strict_target to struct cpufreq_policyRafael J. Wysocki2020-11-101-0/+2
| | | | | | | | | | | | | | | | | | | | Add a new field to be set when the CPUFREQ_GOV_STRICT_TARGET flag is set for the current governor to struct cpufreq_policy, so that the drivers needing to check CPUFREQ_GOV_STRICT_TARGET do not have to access the governor object during every frequency transition. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* | cpufreq: Introduce governor flagsRafael J. Wysocki2020-11-101-1/+1
|/ | | | | | | | | | | | A new cpufreq governor flag will be added subsequently, so replace the bool dynamic_switching fleid in struct cpufreq_governor with a flags field and introduce CPUFREQ_GOV_DYNAMIC_SWITCHING to set for the "dynamic switching" governors instead of it. No intentional functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* cpufreq: Introduce cpufreq_driver_test_flags()Rafael J. Wysocki2020-10-291-0/+12
| | | | | | | | | | | Add a helper function to test the flags of the cpufreq driver in use againt a given flags mask. In particular, this will be needed to test the CPUFREQ_NEED_UPDATE_LIMITS cpufreq driver flag in the schedutil governor. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Introduce CPUFREQ_NEED_UPDATE_LIMITS driver flagRafael J. Wysocki2020-10-271-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | Generally, a cpufreq driver may need to update some internal upper and lower frequency boundaries on policy max and min changes, respectively, but currently this does not work if the target frequency does not change along with the policy limit. Namely, if the target frequency does not change along with the policy min or max, the "target_freq == policy->cur" check in __cpufreq_driver_target() prevents driver callbacks from being invoked and they do not even have a chance to update the corresponding internal boundary. This particularly affects the "powersave" and "performance" governors that always set the target frequency to one of the policy limits and it never changes when the other limit is updated. To allow cpufreq the drivers needing to update internal frequency boundaries on policy limits changes to avoid this issue, introduce a new driver flag, CPUFREQ_NEED_UPDATE_LIMITS, that (when set) will neutralize the check mentioned above. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* cpufreq: Improve code around unlisted freq checkViresh Kumar2020-10-161-8/+7
| | | | | | | | | | | | | | | | | | | The cpufreq core checks if the frequency programmed by the bootloaders is not listed in the freq table and programs one from the table in such a case. This is done only if the driver has set the CPUFREQ_NEED_INITIAL_FREQ_CHECK flag. Currently we print two separate messages, with almost the same content, and do this with a pr_warn() which may be a bit too much as the driver only asked us to check this as it expected this to be the case. Lower down the severity of the print message by switching to pr_info() instead and print a single message only. Reported-by: Sumit Gupta <sumitg@nvidia.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Sumit Gupta <sumitg@nvidia.com> Tested-by: Sumit Gupta <sumitg@nvidia.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq,arm,arm64: restructure definitions of arch_set_freq_scale()Ionela Voinescu2020-10-081-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Compared to other arch_* functions, arch_set_freq_scale() has an atypical weak definition that can be replaced by a strong architecture specific implementation. The more typical support for architectural functions involves defining an empty stub in a header file if the symbol is not already defined in architecture code. Some examples involve: - #define arch_scale_freq_capacity topology_get_freq_scale - #define arch_scale_freq_invariant topology_scale_freq_invariant - #define arch_scale_cpu_capacity topology_get_cpu_scale - #define arch_update_cpu_topology topology_update_cpu_topology - #define arch_scale_thermal_pressure topology_get_thermal_pressure - #define arch_set_thermal_pressure topology_set_thermal_pressure Bring arch_set_freq_scale() in line with these functions by renaming it to topology_set_freq_scale() in the arch topology driver, and by defining the arch_set_freq_scale symbol to point to the new function for arm and arm64. While there are other users of the arch_topology driver, this patch defines arch_set_freq_scale for arm and arm64 only, due to their existing definitions of arch_scale_freq_capacity. This is the getter function of the frequency invariance scale factor and without a getter function, the setter function - arch_set_freq_scale() has not purpose. Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> (BL_SWITCHER and topology parts) Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Move traces and update to policy->cur to cpufreq coreViresh Kumar2020-10-051-0/+7
| | | | | | | | | | | The cpufreq core handles the updates to policy->cur and recording of cpufreq trace events for all the governors except schedutil's fast switch case. Move that as well to cpufreq core for consistency and readability. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: stats: Enable stats for fast-switch as wellViresh Kumar2020-10-051-0/+4
| | | | | | | | Now that all the blockers are gone for enabling stats in fast-switching case, enable it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* arch_topology, cpufreq: constify arch_* cpumasksValentin Schneider2020-09-181-2/+3
| | | | | | | | | | | | | | The passed cpumask arguments to arch_set_freq_scale() and arch_freq_counters_available() are only iterated over, so reflect this in the prototype. This also allows to pass system cpumasks like cpu_online_mask without getting a warning. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: report whether cpufreq supports Frequency Invariance (FI)Ionela Voinescu2020-09-181-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that the update of the FI scale factor is done in cpufreq core for selected functions - target(), target_index() and fast_switch(), we can provide feedback to the task scheduler and architecture code on whether cpufreq supports FI. For this purpose provide an external function to expose whether the cpufreq drivers support FI, by using a static key. The logic behind the enablement of cpufreq-based invariance is as follows: - cpufreq-based invariance is disabled by default - cpufreq-based invariance is enabled if any of the callbacks above is implemented while the unsupported setpolicy() is not The cpufreq_supports_freq_invariance() function only returns whether cpufreq is instrumented with the arch_set_freq_scale() calls that result in support for frequency invariance. Due to the lack of knowledge on whether the implementation of arch_set_freq_scale() actually results in the setting of a scale factor based on cpufreq information, it is up to the architecture code to ensure the setting and provision of the scale factor to the scheduler. Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: move invariance setter calls in cpufreq coreIonela Voinescu2020-09-181-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To properly scale its per-entity load-tracking signals, the task scheduler needs to be given a frequency scale factor, i.e. some image of the current frequency the CPU is running at. Currently, this scale can be computed either by using counters (APERF/MPERF on x86, AMU on arm64), or by piggy-backing on the frequency selection done by cpufreq. For the latter, drivers have to explicitly set the scale factor themselves, despite it being purely boiler-plate code: the required information depends entirely on the kind of frequency switch callback implemented by the driver, i.e. either of: target_index(), target(), fast_switch() and setpolicy(). The fitness of those callbacks with regard to driving the Frequency Invariance Engine (FIE) is studied below: target_index() ============== Documentation states that the chosen frequency "must be determined by freq_table[index].frequency". It isn't clear if it *has* to be that frequency, or if it can use that frequency value to do some computation that ultimately leads to a different frequency selection. All drivers go for the former, while the vexpress-spc-cpufreq has an atypical implementation which is handled separately. Therefore, the hook works on the assumption the core can use freq_table[index].frequency. target() ======= This has been flagged as deprecated since: commit 9c0ebcf78fde ("cpufreq: Implement light weight ->target_index() routine") It also doesn't have that many users: gx-suspmod.c:439: .target = cpufreq_gx_target, s3c24xx-cpufreq.c:428: .target = s3c_cpufreq_target, intel_pstate.c:2528: .target = intel_cpufreq_target, cppc_cpufreq.c:401: .target = cppc_cpufreq_set_target, cpufreq-nforce2.c:371: .target = nforce2_target, sh-cpufreq.c:163: .target = sh_cpufreq_target, pcc-cpufreq.c:573: .target = pcc_cpufreq_target, Similarly to the path taken for target_index() calls in the cpufreq core during a frequency change, all of the drivers above will mark the end of a frequency change by a call to cpufreq_freq_transition_end(). Therefore, cpufreq_freq_transition_end() can be used as the location for the arch_set_freq_scale() call to potentially inform the scheduler of the frequency change. This change maintains the previous functionality for the drivers that implement the target_index() callback, while also adding support for the few drivers that implement the deprecated target() callback. fast_switch() ============= This callback *has* to return the frequency that was selected. setpolicy() =========== This callback does not have any designated way of informing what was the end choice. But there are only two drivers using setpolicy(), and none of them have current FIE support: drivers/cpufreq/longrun.c:281: .setpolicy = longrun_set_policy, drivers/cpufreq/intel_pstate.c:2215: .setpolicy = intel_pstate_set_policy, The intel_pstate is known to use counter-driven frequency invariance. Conclusion ========== Given that the significant majority of current FIE enabled drivers use callbacks that lend themselves to triggering the setting of the FIE scale factor in a generic way, move the invariance setter calls to cpufreq core. As a result of setting the frequency scale factor in cpufreq core, after callbacks that lend themselves to trigger it, remove this functionality from the driver side. To be noted that despite marking a successful frequency change, many cpufreq drivers will consider the new frequency as the requested frequency, although this is might not be the one granted by the hardware. Therefore, the call to arch_set_freq_scale() is a "best effort" one, and it is up to the architecture if the new frequency is used in the new frequency scale factor setting (determined by the implementation of arch_set_freq_scale()) or eventually used by the scheduler (determined by the implementation of arch_scale_freq_capacity()). The architecture is in a better position to decide if it has better methods to obtain more accurate information regarding the current frequency and use that information instead (for example, the use of counters). Also, the implementation to arch_set_freq_scale() will now have to handle error conditions (current frequency == 0) in order to prevent the overhead in cpufreq core when the default arch_set_freq_scale() implementation is used. Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com> Suggested-by: Valentin Schneider <valentin.schneider@arm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: No need to verify cpufreq_driver in show_scaling_cur_freq()Viresh Kumar2020-08-271-2/+1
| | | | | | | | "cpufreq_driver" is guaranteed to be valid here, no need to check it here. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: intel_pstate: Implement passive mode with HWP enabledRafael J. Wysocki2020-08-111-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow intel_pstate to work in the passive mode with HWP enabled and make it set the HWP minimum performance limit (HWP floor) to the P-state value given by the target frequency supplied by the cpufreq governor, so as to prevent the HWP algorithm and the CPU scheduler from working against each other, at least when the schedutil governor is in use, and update the intel_pstate documentation accordingly. Among other things, this allows utilization clamps to be taken into account, at least to a certain extent, when intel_pstate is in use and makes it more likely that sufficient capacity for deadline tasks will be provided. After this change, the resulting behavior of an HWP system with intel_pstate in the passive mode should be close to the behavior of the analogous non-HWP system with intel_pstate in the passive mode, except that the HWP algorithm is generally allowed to make the CPU run at a frequency above the floor P-state set by intel_pstate in the entire available range of P-states, while without HWP a CPU can run in a P-state above the requested one if the latter falls into the range of turbo P-states (referred to as the turbo range) or if the P-states of all CPUs in one package are coordinated with each other at the hardware level. [Note that in principle the HWP floor may not be taken into account by the processor if it falls into the turbo range, in which case the processor has a license to choose any P-state, either below or above the HWP floor, just like a non-HWP processor in the case when the target P-state falls into the turbo range.] With this change applied, intel_pstate in the passive mode assumes complete control over the HWP request MSR and concurrent changes of that MSR (eg. via the direct MSR access interface) are overridden by it. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Reviewed-by: Francisco Jerez <currojerez@riseup.net>
* Merge branch 'cpufreq/arm/linux-next' of ↵Rafael J. Wysocki2020-08-041-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm Pull ARM cpufreq driver changes for v5.9-rc1 from Viresh Kumar: "Here are the details: - Adaptive voltage scaling (AVS) support and minor cleanups for brcmstb driver (Florian Fainelli and Markus Mayer). - A new tegra driver and cleanup for the existing one (Sumit Gupta and Jon Hunter). - Bandwidth level support for Qcom driver along with OPP changes (Sibi Sankar). - Cleanups to sti, cpufreq-dt, ap806, CPPC drivers (Viresh Kumar, Lee Jones, Ivan Kokshaysky, Sven Auhagen, and Xin Hao). - Make schedutil default governor for ARM (Valentin Schneider). - Fix dependency issues for imx (Walter Lozano). - Cleanup around cached_resolved_idx in cpufreq core (Viresh Kumar)." * 'cpufreq/arm/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: cpufreq: make schedutil the default for arm and arm64 cpufreq: cached_resolved_idx can not be negative cpufreq: Add Tegra194 cpufreq driver dt-bindings: arm: Add NVIDIA Tegra194 CPU Complex binding cpufreq: imx: Select NVMEM_IMX_OCOTP cpufreq: sti-cpufreq: Fix some formatting and misspelling issues cpufreq: tegra186: Simplify probe return path cpufreq: CPPC: Reuse caps variable in few routines cpufreq: ap806: fix cpufreq driver needs ap cpu clk cpufreq: cppc: Reorder code and remove apply_hisi_workaround variable cpufreq: dt: fix oops on armada37xx cpufreq: brcmstb-avs-cpufreq: send S2_ENTER / S2_EXIT commands to AVS cpufreq: brcmstb-avs-cpufreq: Support polling AVS firmware cpufreq: brcmstb-avs-cpufreq: more flexible interface for __issue_avs_command() cpufreq: qcom: Disable fast switch when scaling DDR/L3 cpufreq: qcom: Update the bandwidth levels on frequency change OPP: Add and export helper to set bandwidth cpufreq: blacklist SC7180 in cpufreq-dt-platdev cpufreq: blacklist SDM845 in cpufreq-dt-platdev
| * cpufreq: cached_resolved_idx can not be negativeViresh Kumar2020-07-301-1/+1
| | | | | | | | | | | | | | | | | | It is not possible for cached_resolved_idx to be invalid here as the cpufreq core always sets index to a positive value. Change its type to unsigned int and fix qcom usage a bit. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
* | cpufreq: cpufreq: Demote lots of function headers unworthy of kerneldoc statusLee Jones2020-07-151-15/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Also provide missing function parameter description for 'cpu' and 'policy'. Fixes the following W=1 kernel build warning(s): drivers/cpufreq/cpufreq.c:60: warning: cannot understand function prototype: 'struct cpufreq_driver *cpufreq_driver; ' drivers/cpufreq/cpufreq.c:90: warning: Function parameter or member 'cpufreq_policy_notifier_list' not described in 'BLOCKING_NOTIFIER_HEAD' drivers/cpufreq/cpufreq.c:312: warning: Function parameter or member 'val' not described in 'adjust_jiffies' drivers/cpufreq/cpufreq.c:312: warning: Function parameter or member 'ci' not described in 'adjust_jiffies' drivers/cpufreq/cpufreq.c:538: warning: Function parameter or member 'policy' not described in 'cpufreq_driver_resolve_freq' drivers/cpufreq/cpufreq.c:686: warning: Function parameter or member 'file_name' not described in 'show_one' drivers/cpufreq/cpufreq.c:686: warning: Function parameter or member 'object' not described in 'show_one' drivers/cpufreq/cpufreq.c:731: warning: Function parameter or member 'file_name' not described in 'store_one' drivers/cpufreq/cpufreq.c:731: warning: Function parameter or member 'object' not described in 'store_one' drivers/cpufreq/cpufreq.c:741: warning: Function parameter or member 'policy' not described in 'show_cpuinfo_cur_freq' drivers/cpufreq/cpufreq.c:741: warning: Function parameter or member 'buf' not described in 'show_cpuinfo_cur_freq' drivers/cpufreq/cpufreq.c:754: warning: Function parameter or member 'policy' not described in 'show_scaling_governor' drivers/cpufreq/cpufreq.c:754: warning: Function parameter or member 'buf' not described in 'show_scaling_governor' drivers/cpufreq/cpufreq.c:770: warning: Function parameter or member 'policy' not described in 'store_scaling_governor' drivers/cpufreq/cpufreq.c:770: warning: Function parameter or member 'buf' not described in 'store_scaling_governor' drivers/cpufreq/cpufreq.c:770: warning: Function parameter or member 'count' not described in 'store_scaling_governor' drivers/cpufreq/cpufreq.c:806: warning: Function parameter or member 'policy' not described in 'show_scaling_driver' drivers/cpufreq/cpufreq.c:806: warning: Function parameter or member 'buf' not described in 'show_scaling_driver' drivers/cpufreq/cpufreq.c:815: warning: Function parameter or member 'policy' not described in 'show_scaling_available_governors' drivers/cpufreq/cpufreq.c:815: warning: Function parameter or member 'buf' not described in 'show_scaling_available_governors' drivers/cpufreq/cpufreq.c:859: warning: Function parameter or member 'policy' not described in 'show_related_cpus' drivers/cpufreq/cpufreq.c:859: warning: Function parameter or member 'buf' not described in 'show_related_cpus' drivers/cpufreq/cpufreq.c:867: warning: Function parameter or member 'policy' not described in 'show_affected_cpus' drivers/cpufreq/cpufreq.c:867: warning: Function parameter or member 'buf' not described in 'show_affected_cpus' drivers/cpufreq/cpufreq.c:901: warning: Function parameter or member 'policy' not described in 'show_bios_limit' drivers/cpufreq/cpufreq.c:901: warning: Function parameter or member 'buf' not described in 'show_bios_limit' drivers/cpufreq/cpufreq.c:1625: warning: Function parameter or member 'dev' not described in 'cpufreq_remove_dev' drivers/cpufreq/cpufreq.c:1625: warning: Function parameter or member 'sif' not described in 'cpufreq_remove_dev' drivers/cpufreq/cpufreq.c:2380: warning: Function parameter or member 'cpu' not described in 'cpufreq_get_policy' drivers/cpufreq/cpufreq.c:2771: warning: Function parameter or member 'driver' not described in 'cpufreq_unregister_driver' Signed-off-by: Lee Jones <lee.jones@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | cpufreq: Remove the weakly defined cpufreq_default_governor()Viresh Kumar2020-07-021-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The default cpufreq governor is chosen with the help of a "choice" option in the Kconfig which will always end up selecting one of the governors and so the weakly defined definition of cpufreq_default_governor() will never get called. Moreover, this makes us skip the checking of the return value of that routine as it will always be non NULL. If the Kconfig option changes in future, then we will start getting a link error instead (and it won't go unnoticed as in the case of the weak definition). Suggested-by: Quentin Perret <qperret@google.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | cpufreq: Specify default governor on command lineQuentin Perret2020-07-021-9/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the only way to specify the default CPUfreq governor is via Kconfig options, which suits users who can build the kernel themselves perfectly. However, for those who use a distro-like kernel (such as Android, with the Generic Kernel Image project), the only way to use a non-default governor is to boot to userspace, and to then switch using the sysfs interface. Being able to specify the default governor on the command line, like is the case for cpuidle, would allow those users to specify their governor of choice earlier on, and to simplify the userspace boot procedure slighlty. To support this use-case, add a kernel command line parameter allowing the default governor for CPUfreq to be specified, which takes precedence over the built-in default. This implementation has one notable limitation: the default governor must be registered before the driver. This is solved for builtin governors and drivers using appropriate *_initcall() functions. And in the modular case, this must be reflected as a constraint on the module loading order. Signed-off-by: Quentin Perret <qperret@google.com> [ Viresh: Converted 'default_governor' to a string and parsing it only at initcall level, and several updates to cpufreq_init_policy(). ] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | cpufreq: Fix locking issues with governorsViresh Kumar2020-07-021-23/+35
|/ | | | | | | | | | | | | | The locking around governors handling isn't adequate currently. The list of governors should never be traversed without the locking in place. Also governor modules must not be removed while the code in them is still in use. Reported-by: Quentin Perret <qperret@google.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: All applicable <stable@vger.kernel.org> [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: change '.set_boost' to act on one policyXiongfeng Wang2020-06-051-26/+31
| | | | | | | | | | | | | | | | | | | | | | | | Macro 'for_each_active_policy()' is defined internally. To avoid some cpufreq driver needing this macro to iterate over all the policies in '.set_boost' callback, we redefine '.set_boost' to act on only one policy and pass the policy as an argument. 'cpufreq_boost_trigger_state()' iterates over all the policies to set boost for the system. This is preparation for adding SW BOOST support for CPPC. To protect Boost enable/disable by sysfs from CPU online/offline, add 'cpu_hotplug_lock' before calling '.set_boost' for each CPU. Also move the lock from 'set_boost()' to 'store_cpb()' in acpi_cpufreq. Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Suggested-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Fix up cpufreq_boost_set_sw()Rafael J. Wysocki2020-05-181-5/+6
| | | | | | | | | | | | | | | | | | | After commit 18c49926c4bf ("cpufreq: Add QoS requests for userspace constraints") the return value of freq_qos_update_request(), that can be 1, passed by cpufreq_boost_set_sw() to its caller sometimes confuses the latter, which only expects to see 0 or negative error codes, so notice that cpufreq_boost_set_sw() can return an error code (which should not be -EINVAL for that matter) as soon as the first policy without a frequency table is found (because either all policies have a frequency table or none of them have it) and rework it to meet its caller's expectations. Fixes: 18c49926c4bf ("cpufreq: Add QoS requests for userspace constraints") Reported-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Reported-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: 5.3+ <stable@vger.kernel.org> # 5.3+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Merge tag 'arm64-upstream' of ↵Linus Torvalds2020-03-311-0/+20
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "The bulk is in-kernel pointer authentication, activity monitors and lots of asm symbol annotations. I also queued the sys_mremap() patch commenting the asymmetry in the address untagging. Summary: - In-kernel Pointer Authentication support (previously only offered to user space). - ARM Activity Monitors (AMU) extension support allowing better CPU utilisation numbers for the scheduler (frequency invariance). - Memory hot-remove support for arm64. - Lots of asm annotations (SYM_*) in preparation for the in-kernel Branch Target Identification (BTI) support. - arm64 perf updates: ARMv8.5-PMU 64-bit counters, refactoring the PMU init callbacks, support for new DT compatibles. - IPv6 header checksum optimisation. - Fixes: SDEI (software delegated exception interface) double-lock on hibernate with shared events. - Minor clean-ups and refactoring: cpu_ops accessor, cpu_do_switch_mm() converted to C, cpufeature finalisation helper. - sys_mremap() comment explaining the asymmetric address untagging behaviour" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (81 commits) mm/mremap: Add comment explaining the untagging behaviour of mremap() arm64: head: Convert install_el2_stub to SYM_INNER_LABEL arm64: Introduce get_cpu_ops() helper function arm64: Rename cpu_read_ops() to init_cpu_ops() arm64: Declare ACPI parking protocol CPU operation if needed arm64: move kimage_vaddr to .rodata arm64: use mov_q instead of literal ldr arm64: Kconfig: verify binutils support for ARM64_PTR_AUTH lkdtm: arm64: test kernel pointer authentication arm64: compile the kernel with ptrauth return address signing kconfig: Add support for 'as-option' arm64: suspend: restore the kernel ptrauth keys arm64: __show_regs: strip PAC from lr in printk arm64: unwind: strip PAC from kernel addresses arm64: mask PAC bits of __builtin_return_address arm64: initialize ptrauth keys for kernel booting task arm64: initialize and switch ptrauth kernel keys arm64: enable ptrauth earlier arm64: cpufeature: handle conflicts based on capability arm64: cpufeature: Move cpu capability helpers inside C file ...
| * cpufreq: add function to get the hardware max frequencyIonela Voinescu2020-03-061-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add weak function to return the hardware maximum frequency of a CPU, with the default implementation returning cpuinfo.max_freq, which is the best information we can generically get from the cpufreq framework. The default can be overwritten by a strong function in platforms that want to provide an alternative implementation, with more accurate information, obtained either from hardware or firmware. Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* | cpufreq: Fix policy initialization for internal governor driversRafael J. Wysocki2020-02-271-2/+10
|/ | | | | | | | | | | | | | | | | | Before commit 1e4f63aecb53 ("cpufreq: Avoid creating excessively large stack frames") the initial value of the policy field in struct cpufreq_policy set by the driver's ->init() callback was implicitly passed from cpufreq_init_policy() to cpufreq_set_policy() if the default governor was neither "performance" nor "powersave". After that commit, however, cpufreq_init_policy() must take that case into consideration explicitly and handle it as appropriate, so make that happen. Fixes: 1e4f63aecb53 ("cpufreq: Avoid creating excessively large stack frames") Link: https://lore.kernel.org/linux-pm/39fb762880c27da110086741315ca8b111d781cd.camel@gmail.com/ Reported-by: Artem Bityutskiy <dedekind1@gmail.com> Cc: 5.4+ <stable@vger.kernel.org> # 5.4+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* cpufreq: Make cpufreq_global_kobject staticYangtao Li2020-02-031-3/+2
| | | | | | | | | | | | The cpufreq_global_kobject is only used internally by cpufreq.c after commit 2361be236662 ("cpufreq: Don't create empty /sys/devices/system/cpu/cpufreq directory"). Make it static. Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> [ rjw: Add empty line after cpufreq_global_kobject definition ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Avoid creating excessively large stack framesRafael J. Wysocki2020-01-271-77/+70
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the process of modifying a cpufreq policy, the cpufreq core makes a copy of it including all of the internals which is stored on the CPU stack. Because struct cpufreq_policy is relatively large, this may cause the size of the stack frame to exceed the 2 KB limit and so the GCC complains when -Wframe-larger-than= is used. In fact, it is not necessary to copy the entire policy structure in order to modify it, however. First, because cpufreq_set_policy() obtains the min and max policy limits from frequency QoS now, it is not necessary to pass the limits to it from the callers. The only things that need to be passed to it from there are the new governor pointer or (if there is a built-in governor in the driver) the "policy" value representing the governor choice. They both can be passed as individual arguments, though, so make cpufreq_set_policy() take them this way and rework its callers accordingly. This avoids making copies of cpufreq policies in the callers of cpufreq_set_policy(). Second, cpufreq_set_policy() still needs to pass the new policy data to the ->verify() callback of the cpufreq driver whose task is to sanitize the min and max policy limits. It still does not need to make a full copy of struct cpufreq_policy for this purpose, but it needs to pass a few items from it to the driver in case they are needed (different drivers have different needs in that respect and all of them have to be covered). For this reason, introduce struct cpufreq_policy_data to hold copies of the members of struct cpufreq_policy used by the existing ->verify() driver callbacks and pass a pointer to a temporary structure of that type to ->verify() (instead of passing a pointer to full struct cpufreq_policy to it). While at it, notice that intel_pstate and longrun don't really need to verify the "policy" value in struct cpufreq_policy, so drop those check from them to avoid copying "policy" into struct cpufreq_policy_data (which allows it to be slightly smaller). Also while at it fix up white space in a couple of places and make cpufreq_set_policy() static (as it can be so). Fixes: 3000ce3c52f8 ("cpufreq: Use per-policy frequency QoS") Link: https://lore.kernel.org/linux-pm/CAMuHMdX6-jb1W8uC2_237m8ctCpsnGp=JCxqt8pCWVqNXHmkVg@mail.gmail.com Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: 5.4+ <stable@vger.kernel.org> # 5.4+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* Merge tag 'pm-5.5-rc1' of ↵Linus Torvalds2019-11-261-1/+17
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These include cpuidle changes to use nanoseconds (instead of microseconds) as the unit of time and to simplify checks for disabled idle states in the idle loop, some cpuidle fixes and governor updates, assorted cpufreq updates (driver updates mostly and a few core fixes and cleanups), devfreq updates (dominated by the tegra30 driver changes), new CPU IDs for the RAPL power capping driver, relatively minor updates of the generic power domains (genpd) and operation performance points (OPP) frameworks, and assorted fixes and cleanups. There are also two maintainer information updates: Chanwoo Choi will be maintaining the devfreq subsystem going forward and Todd Brandt is going to maintain the pm-graph utility (created by him). Specifics: - Use nanoseconds (instead of microseconds) as the unit of time in the cpuidle core and simplify checks for disabled idle states in the idle loop (Rafael Wysocki) - Fix and clean up the teo cpuidle governor (Rafael Wysocki) - Fix the cpuidle registration error code path (Zhenzhong Duan) - Avoid excessive vmexits in the ACPI cpuidle driver (Yin Fengwei) - Extend the idle injection infrastructure to be able to measure the requested duration in nanoseconds and to allow an exit latency limit for idle states to be specified (Daniel Lezcano) - Fix cpufreq driver registration and clarify a comment in the cpufreq core (Viresh Kumar) - Add NULL checks to the show() and store() methods of sysfs attributes exposed by cpufreq (Kai Shen) - Update cpufreq drivers: * Fix for a plain int as pointer warning from sparse in intel_pstate (Jamal Shareef) * Fix for a hardcoded number of CPUs and stack bloat in the powernv driver (John Hubbard) * Updates to the ti-cpufreq driver and DT files to support new platforms and migrate bindings from opp-v1 to opp-v2 (Adam Ford, H. Nikolaus Schaller) * Merging of the arm_big_little and vexpress-spc drivers and related cleanup (Sudeep Holla) * Fix for imx's default speed grade value (Anson Huang) * Minor cleanup of the s3c64xx driver (Nathan Chancellor) * CPU speed bin detection fix for sun50i (Ondrej Jirman) - Appoint Chanwoo Choi as the new devfreq maintainer. - Update the devfreq core: * Check NULL governor in available_governors_show sysfs to prevent showing wrong governor information and fix a race condition between devfreq_update_status() and trans_stat_show() (Leonard Crestez) * Add new 'interrupt-driven' flag for devfreq governors to allow interrupt-driven governors to prevent the devfreq core from polling devices for status (Dmitry Osipenko) * Improve an error message in devfreq_add_device() (Matthias Kaehlcke) - Update devfreq drivers: * tegra30 driver fixes and cleanups (Dmitry Osipenko) * Removal of unused property from dt-binding documentation for the exynos-bus driver (Kamil Konieczny) * exynos-ppmu cleanup and DT bindings update (Lukasz Luba, Marek Szyprowski) - Add new CPU IDs for CometLake Mobile and Desktop to the Intel RAPL power capping driver (Zhang Rui) - Allow device initialization in the generic power domains (genpd) framework to be more straightforward and clean it up (Ulf Hansson) - Add support for adjusting OPP voltages at run time to the OPP framework (Stephen Boyd) - Avoid freeing memory that has never been allocated in the hibernation core (Andy Whitcroft) - Clean up function headers in a header file and coding style in the wakeup IRQs handling code (Ulf Hansson, Xiaofei Tan) - Clean up the SmartReflex adaptive voltage scaling (AVS) driver for ARM (Ben Dooks, Geert Uytterhoeven) - Wrap power management documentation to fit in 80 columns (Bjorn Helgaas) - Add pm-graph utility entry to MAINTAINERS (Todd Brandt) - Update the cpupower utility: * Fix the handling of set and info subcommands (Abhishek Goel) * Fix build warnings (Nathan Chancellor) * Improve mperf_monitor handling (Janakarajan Natarajan)" * tag 'pm-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (83 commits) PM: Wrap documentation to fit in 80 columns cpuidle: Pass exit latency limit to cpuidle_use_deepest_state() cpuidle: Allow idle injection to apply exit latency limit cpuidle: Introduce cpuidle_driver_state_disabled() for driver quirks cpuidle: teo: Avoid code duplication in conditionals cpufreq: Register drivers only after CPU devices have been registered cpuidle: teo: Avoid using "early hits" incorrectly cpuidle: teo: Exclude cpuidle overhead from computations PM / Domains: Convert to dev_to_genpd_safe() in genpd_syscore_switch() mmc: tmio: Avoid boilerplate code in ->runtime_suspend() PM / Domains: Implement the ->start() callback for genpd PM / Domains: Introduce dev_pm_domain_start() ARM: OMAP2+: SmartReflex: add omap_sr_pdata definition PM / wakeirq: remove unnecessary parentheses power: avs: smartreflex: Remove superfluous cast in debugfs_create_file() call cpuidle: Use nanoseconds as the unit of time PM / OPP: Support adjusting OPP voltages at runtime PM / core: Clean up some function headers in power.h cpufreq: Add NULL checks to show() and store() methods of cpufreq cpufreq: intel_pstate: Fix plain int as pointer warning from sparse ...
| * cpufreq: Register drivers only after CPU devices have been registeredViresh Kumar2019-11-141-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The cpufreq core heavily depends on the availability of the struct device for CPUs and if they aren't available at the time cpufreq driver is registered, we will never succeed in making cpufreq work. This happens due to following sequence of events: - cpufreq_register_driver() - subsys_interface_register() - return 0; //successful registration of driver ... at a later point of time - register_cpu(); - device_register(); - bus_probe_device(); - sif->add_dev(); - cpufreq_add_dev(); - get_cpu_device(); //FAILS - per_cpu(cpu_sys_devices, num) = &cpu->dev; //used by get_cpu_device() - return 0; //CPU registered successfully Because the per-cpu variable cpu_sys_devices is set only after the CPU device is regsitered, cpufreq will never be able to get it when cpufreq_add_dev() is called. This patch avoids this failure by making sure device structure of at least CPU0 is available when the cpufreq driver is registered, else return -EPROBE_DEFER. Reported-by: Bjorn Andersson <bjorn.andersson@linaro.org> Co-developed-by: Amit Kucheria <amit.kucheria@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Amit Kucheria <amit.kucheria@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| * cpufreq: Add NULL checks to show() and store() methods of cpufreqKai Shen2019-11-081-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add NULL checks to show() and store() in cpufreq.c to avoid attempts to invoke a NULL callback. Though some interfaces of cpufreq are set as read-only, users can still get write permission using chmod which can lead to a kernel crash, as follows: chmod +w /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq echo 1 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq This bug was found in linux 4.19. Signed-off-by: Kai Shen <shenkai8@huawei.com> Reported-by: Feilong Lin <linfeilong@huawei.com> Reviewed-by: Feilong Lin <linfeilong@huawei.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Subject & changelog ] Cc: All applicable <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| * cpufreq: Clarify the comment in cpufreq_set_policy()Viresh Kumar2019-11-041-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | One of the responsibility of the ->verify() callback is to make sure that the policy's min frequency is <= max frequency as this isn't guaranteed by the QoS framework which gave us those values. Update the comment in cpufreq_set_policy() to clarify that. Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Minor changes of the new comment ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | cpufreq: Use vtime aware kcpustat accessors for user timeFrederic Weisbecker2019-11-211-7/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | We can now safely read user and guest kcpustat fields on nohz_full CPUs. Use the appropriate accessors. Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wanpeng Li <wanpengli@tencent.com> Link: https://lkml.kernel.org/r/20191121024430.19938-5-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge tag 'v5.4-rc7' into sched/core, to pick up fixesIngo Molnar2019-11-111-43/+29
|\| | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * cpufreq: Cancel policy update work scheduled before freeingSudeep Holla2019-10-221-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Scheduled policy update work may end up racing with the freeing of the policy and unregistering the driver. One possible race is as below, where the cpufreq_driver is unregistered, but the scheduled work gets executed at later stage when, cpufreq_driver is NULL (i.e. after freeing the policy and driver). Unable to handle kernel NULL pointer dereference at virtual address 0000001c pgd = (ptrval) [0000001c] *pgd=80000080204003, *pmd=00000000 Internal error: Oops: 206 [#1] SMP THUMB2 Modules linked in: CPU: 0 PID: 34 Comm: kworker/0:1 Not tainted 5.4.0-rc3-00006-g67f5a8081a4b #86 Hardware name: ARM-Versatile Express Workqueue: events handle_update PC is at cpufreq_set_policy+0x58/0x228 LR is at dev_pm_qos_read_value+0x77/0xac Control: 70c5387d Table: 80203000 DAC: fffffffd Process kworker/0:1 (pid: 34, stack limit = 0x(ptrval)) (cpufreq_set_policy) from (refresh_frequency_limits.part.24+0x37/0x48) (refresh_frequency_limits.part.24) from (handle_update+0x2f/0x38) (handle_update) from (process_one_work+0x16d/0x3cc) (process_one_work) from (worker_thread+0xff/0x414) (worker_thread) from (kthread+0xff/0x100) (kthread) from (ret_from_fork+0x11/0x28) Fixes: 67d874c3b2c6 ("cpufreq: Register notifiers with the PM QoS framework") Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> [ rjw: Cancel the work before dropping the QoS requests ] Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| * cpufreq: Use per-policy frequency QoSRafael J. Wysocki2019-10-211-33/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the CPU device PM QoS used for the management of min and max frequency constraints in cpufreq (and its users) with per-policy frequency QoS to avoid problems with cpufreq policies covering more then one CPU. Namely, a cpufreq driver is registered with the subsys interface which calls cpufreq_add_dev() for each CPU, starting from CPU0, so currently the PM QoS notifiers are added to the first CPU in the policy (i.e. CPU0 in the majority of cases). In turn, when the cpufreq driver is unregistered, the subsys interface doing that calls cpufreq_remove_dev() for each CPU, starting from CPU0, and the PM QoS notifiers are only removed when cpufreq_remove_dev() is called for the last CPU in the policy, say CPUx, which as a rule is not CPU0 if the policy covers more than one CPU. Then, the PM QoS notifiers cannot be removed, because CPUx does not have them, and they are still there in the device PM QoS notifiers list of CPU0, which prevents new PM QoS notifiers from being registered for CPU0 on the next attempt to register the cpufreq driver. The same issue occurs when the first CPU in the policy goes offline before unregistering the driver. After this change it does not matter which CPU is the policy CPU at the driver registration time and whether or not it is online all the time, because the frequency QoS is per policy and not per CPU. Fixes: 67d874c3b2c6 ("cpufreq: Register notifiers with the PM QoS framework") Reported-by: Dmitry Osipenko <digetx@gmail.com> Tested-by: Dmitry Osipenko <digetx@gmail.com> Reported-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Sudeep Holla <sudeep.holla@arm.com> Diagnosed-by: Viresh Kumar <viresh.kumar@linaro.org> Link: https://lore.kernel.org/linux-pm/5ad2624194baa2f53acc1f1e627eb7684c577a19.1562210705.git.viresh.kumar@linaro.org/T/#md2d89e95906b8c91c15f582146173dce2e86e99f Link: https://lore.kernel.org/linux-pm/20191017094612.6tbkwoq4harsjcqv@vireshk-i7/T/#m30d48cc23b9a80467fbaa16e30f90b3828a5a29b Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
| * cpufreq: Avoid cpufreq_suspend() deadlock on system shutdownRafael J. Wysocki2019-10-101-10/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is incorrect to set the cpufreq syscore shutdown callback pointer to cpufreq_suspend(), because that function cannot be run in the syscore stage of system shutdown for two reasons: (a) it may attempt to carry out actions depending on devices that have already been shut down at that point and (b) the RCU synchronization carried out by it may not be able to make progress then. The latter issue has been present since commit 45975c7d21a1 ("rcu: Define RCU-sched API in terms of RCU for Tree RCU PREEMPT builds"), but the former one has been there since commit 90de2a4aa9f3 ("cpufreq: suspend cpufreq governors on shutdown") regardless. Fix that by dropping cpufreq_syscore_ops altogether and making device_shutdown() call cpufreq_suspend() directly before shutting down devices, which is along the lines of what system-wide power management does. Fixes: 45975c7d21a1 ("rcu: Define RCU-sched API in terms of RCU for Tree RCU PREEMPT builds") Fixes: 90de2a4aa9f3 ("cpufreq: suspend cpufreq governors on shutdown") Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: 4.0+ <stable@vger.kernel.org> # 4.0+
* | cpufreq: Use vtime aware kcpustat accessor to fetch CPUTIME_SYSTEMFrederic Weisbecker2019-10-291-1/+1
|/ | | | | | | | | | | | | | | | | | | | Now that we have a vtime safe kcpustat accessor for CPUTIME_SYSTEM, use it to start fixing frozen kcpustat values on nohz_full CPUs. Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J . Wysocki <rjw@rjwysocki.net> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpengli@tencent.com> Link: https://lkml.kernel.org/r/20191016025700.31277-14-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'pm-cpufreq-qos'Rafael J. Wysocki2019-09-051-30/+21
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | * pm-cpufreq-qos: Documentation: cpufreq: Update policy notifier documentation cpufreq: Remove CPUFREQ_ADJUST and CPUFREQ_NOTIFY policy notifier events ACPI: cpufreq: Switch to QoS requests instead of cpufreq notifier video: pxafb: Remove cpufreq policy notifier video: sa1100fb: Remove cpufreq policy notifier arch_topology: Use CPUFREQ_CREATE_POLICY instead of CPUFREQ_NOTIFY cpufreq: powerpc_cbe: Switch to QoS requests for freq limits cpufreq: powerpc: macintosh: Switch to QoS requests for freq limits thermal: cpu_cooling: Switch to QoS requests for freq limits cpufreq: Add policy create/remove notifiers back
| * cpufreq: Remove CPUFREQ_ADJUST and CPUFREQ_NOTIFY policy notifier eventsViresh Kumar2019-09-021-29/+7
| | | | | | | | | | | | | | | | No driver makes reference to these events now, remove them and the code related to them. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| * cpufreq: Add policy create/remove notifiers backViresh Kumar2019-08-101-1/+14
| | | | | | | | | | | | | | | | | | | | | | | | This effectively reverts some changes made by commit f9f41e3ef99 ("cpufreq: Remove policy create/remove notifiers"). We have a new use case for policy create/remove notifiers (for allocating/freeing QoS requests per policy), so add them back. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | cpufreq: Print driver name if cpufreq_suspend() failsFlorian Fainelli2019-08-221-2/+2
| | | | | | | | | | | | | | | | | | | | Instead of printing the policy, which is incidentally a kernel pointer, so with limited interest, print the cpufreq driver name that failed to be suspend, which is more useful for debugging. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | cpufreq: remove redundant assignment to retColin Ian King2019-08-211-1/+1
| | | | | | | | | | | | | | | | | | | | Variable ret is initialized to a value that is never read and it is re-assigned later. The initialization is redundant and can be removed. Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | cpufreq: dev_pm_qos_update_request() can return 1 on successViresh Kumar2019-08-101-1/+1
|/ | | | | | | | | dev_pm_qos_update_request() can return 1 on success, so don't treat it as an error. Fixes: 18c49926c4bf ("cpufreq: Add QoS requests for userspace constraints") Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Merge branch 'pm-cpufreq'Rafael J. Wysocki2019-07-181-65/+151
|\ | | | | | | | | | | | | | | | | | | | | | | | | * pm-cpufreq: cpufreq: Make cpufreq_generic_init() return void cpufreq: imx-cpufreq-dt: Add i.MX8MN support cpufreq: Add QoS requests for userspace constraints cpufreq: intel_pstate: Reuse refresh_frequency_limits() cpufreq: Register notifiers with the PM QoS framework PM / QoS: Add support for MIN/MAX frequency constraints PM / QOS: Pass request type to dev_pm_qos_read_value() PM / QOS: Rename __dev_pm_qos_read_value() and dev_pm_qos_raw_read_value() PM / QOS: Pass request type to dev_pm_qos_{add|remove}_notifier()
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-17 02:49:04 +0000