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2 daysMerge tag 'pm-6.16-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "Once again, the changes are dominated by cpufreq updates, but this time the majority of them are cpufreq core changes, mostly related to the introduction of policy locking guards and __free() usage, and fixes related to boost handling. Still, there is also a significant update of the intel_pstate driver making it register an energy model when running on a hybrid platform which is used for enabling energy-aware scheduling (EAS) if the driver operates in the passive mode (and schedutil is used as the cpufreq governor for all CPUs which is the passive mode default). There are some amd-pstate driver updates too, for a good measure, including the "Requested CPU Min frequency" BIOS option support and new online/offline callbacks. In the cpuidle space, the most significant change is the addition of a C1 demotion on/off sysfs knob to intel_idle which should help some users to configure their systems more precisely. There is also the conversion of the PSCI cpuidle driver to a faux device one and there are two small updates of cpuidle governors. Device power management is also modified quite a bit, especially the handling of devices with asynchronous suspend and resume enabled during system transitions. They are now going to be handled more asynchronously during suspend transitions and somewhat less aggressively during resume transitions. Apart from the above, the operating performance points (OPP) library is now going to use mutex locking guards and scope-based cleanup helpers and there is the usual bunch of assorted fixes and code cleanups. Specifics: - Fix potential division-by-zero error in em_compute_costs() (Yaxiong Tian) - Fix typos in energy model documentation and example driver code (Moon Hee Lee, Atul Kumar Pant) - Rearrange the energy model management code and add a new function for adjusting a CPU energy model after adjusting the capacity of the given CPU to it (Rafael Wysocki) - Refactor cpufreq_online(), add and use cpufreq policy locking guards, use __free() in policy reference counting, and clean up core cpufreq code on top of that (Rafael Wysocki) - Fix boost handling on CPU suspend/resume and sysfs updates (Viresh Kumar) - Fix des_perf clamping with max_perf in amd_pstate_update() (Dhananjay Ugwekar) - Add offline, online and suspend callbacks to the amd-pstate driver, rename and use the existing amd_pstate_epp callbacks in it (Dhananjay Ugwekar) - Add support for the "Requested CPU Min frequency" BIOS option to the amd-pstate driver (Dhananjay Ugwekar) - Reset amd-pstate driver mode after running selftests (Swapnil Sapkal) - Avoid shadowing ret in amd_pstate_ut_check_driver() (Nathan Chancellor) - Add helper for governor checks to the schedutil cpufreq governor and move cpufreq-specific EAS checks to cpufreq (Rafael Wysocki) - Populate the cpu_capacity sysfs entries from the intel_pstate driver after registering asym capacity support (Ricardo Neri) - Add support for enabling Energy-aware scheduling (EAS) to the intel_pstate driver when operating in the passive mode on a hybrid platform (Rafael Wysocki) - Drop redundant cpus_read_lock() from store_local_boost() in the cpufreq core (Seyediman Seyedarab) - Replace sscanf() with kstrtouint() in the cpufreq code and use a symbol instead of a raw number in it (Bowen Yu) - Add support for autonomous CPU performance state selection to the CPPC cpufreq driver (Lifeng Zheng) - OPP: Add dev_pm_opp_set_level() (Praveen Talari) - Introduce scope-based cleanup headers and mutex locking guards in OPP core (Viresh Kumar) - Switch OPP to use kmemdup_array() (Zhang Enpei) - Optimize bucket assignment when next_timer_ns equals KTIME_MAX in the menu cpuidle governor (Zhongqiu Han) - Convert the cpuidle PSCI driver to a faux device one (Sudeep Holla) - Add C1 demotion on/off sysfs knob to the intel_idle driver (Artem Bityutskiy) - Fix typos in two comments in the teo cpuidle governor (Atul Kumar Pant) - Fix denying of auto suspend in pm_suspend_timer_fn() (Charan Teja Kalla) - Move debug runtime PM attributes to runtime_attrs[] (Rafael Wysocki) - Add new devm_ functions for enabling runtime PM and runtime PM reference counting (Bence Csókás) - Remove size arguments from strscpy() calls in the hibernation core code (Thorsten Blum) - Adjust the handling of devices with asynchronous suspend enabled during system suspend and resume to start resuming them immediately after resuming their parents and to start suspending such a device immediately after suspending its first child (Rafael Wysocki) - Adjust messages printed during tasks freezing to avoid using pr_cont() (Andrew Sayers, Paul Menzel) - Clean up unnecessary usage of !! in pm_print_times_init() (Zihuan Zhang) - Add missing wakeup source attribute relax_count to sysfs and remove the space character at the end ofi the string produced by pm_show_wakelocks() (Zijun Hu) - Add configurable pm_test delay for hibernation (Zihuan Zhang) - Disable asynchronous suspend in ucsi_ccg_probe() to prevent the cypd4226 device on Tegra boards from suspending prematurely (Jon Hunter) - Unbreak printing PM debug messages during hibernation and clean up some related code (Rafael Wysocki) - Add a systemd service to run cpupower and change cpupower binding's Makefile to use -lcpupower (John B. Wyatt IV, Francesco Poli)" * tag 'pm-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (72 commits) cpufreq: CPPC: Add support for autonomous selection cpufreq: Update sscanf() to kstrtouint() cpufreq: Replace magic number OPP: switch to use kmemdup_array() PM: freezer: Rewrite restarting tasks log to remove stray *done.* PM: runtime: fix denying of auto suspend in pm_suspend_timer_fn() cpufreq: drop redundant cpus_read_lock() from store_local_boost() cpupower: do not install files to /etc/default/ cpupower: do not call systemctl at install time cpupower: do not write DESTDIR to cpupower.service PM: sleep: Introduce pm_sleep_transition_in_progress() cpufreq/amd-pstate: Avoid shadowing ret in amd_pstate_ut_check_driver() cpufreq: intel_pstate: Document hybrid processor support cpufreq: intel_pstate: EAS: Increase cost for CPUs using L3 cache cpufreq: intel_pstate: EAS support for hybrid platforms PM: EM: Introduce em_adjust_cpu_capacity() PM: EM: Move CPU capacity check to em_adjust_new_capacity() PM: EM: Documentation: Fix typos in example driver code cpufreq: Drop policy locking from cpufreq_policy_is_good_for_eas() PM: sleep: Introduce pm_suspend_in_progress() ...
4 daysMerge branch 'pm-cpuidle'Rafael J. Wysocki
Merge cpuidle updates for 6.16-rc1: - Optimize bucket assignment when next_timer_ns equals KTIME_MAX in the menu cpuidle governor (Zhongqiu Han). - Convert the cpuidle PSCI driver to a faux device one (Sudeep Holla). - Add C1 demotion on/off sysfs knob to the intel_idle driver (Artem Bityutskiy). - Fix typos in two comments in the teo cpuidle governor (Atul Kumar Pant). * pm-cpuidle: cpuidle: psci: Avoid initializing faux device if no DT idle states are present Documentation: ABI: testing: document the new cpuidle sysfs file Documentation: admin-guide: pm: Document intel_idle C1 demotion intel_idle: Add C1 demotion on/off sysfs knob cpuidle: psci: Transition to the faux device interface cpuidle: menu: Optimize bucket assignment when next_timer_ns equals KTIME_MAX cpuidle: teo: Fix typos in two comments
2025-05-13cpufreq: intel_pstate: Document hybrid processor supportRafael J. Wysocki
Describe the support for hybrid processors in intel_pstate, including the CAS and EAS support, in the admin-guide documentation. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://patch.msgid.link/1935040.CQOukoFCf9@rjwysocki.net
2025-04-15Documentation: admin-guide: pm: Document intel_idle C1 demotionArtem Bityutskiy
Document the intel_idle driver sysfs file for enabling/disabling C1 demotion. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Link: https://patch.msgid.link/20250317135541.1471754-3-dedekind1@gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-04-14cpufreq: editing corrections to cpufreq.rstRandy Dunlap
Change a few words and abbreviations/punctuation. Change one echo command to include a trailing '`'. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: linux-pm@vger.kernel.org Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250405001447.4039463-1-rdunlap@infradead.org
2025-03-25Merge tag 'pm-6.15-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These are dominated by cpufreq updates which in turn are dominated by updates related to boost support in the core and drivers and amd-pstate driver optimizations. Apart from the above, there are some cpuidle updates including a rework of the most recent idle intervals handling in the venerable menu governor that leads to significant improvements in some performance benchmarks, as the governor is now more likely to predict a shorter idle duration in some cases, and there are updates of the core device power management code, mostly related to system suspend and resume, that should help to avoid potential issues arising when the drivers of devices depending on one another want to use different optimizations. There is also a usual collection of assorted fixes and cleanups, including removal of some unused code. Specifics: - Manage sysfs attributes and boost frequencies efficiently from cpufreq core to reduce boilerplate code in drivers (Viresh Kumar) - Minor cleanups to cpufreq drivers (Aaron Kling, Benjamin Schneider, Dhananjay Ugwekar, Imran Shaik, zuoqian) - Migrate some cpufreq drivers to using for_each_present_cpu() (Jacky Bai) - cpufreq-qcom-hw DT binding fixes (Krzysztof Kozlowski) - Use str_enable_disable() helper in cpufreq_online() (Lifeng Zheng) - Optimize the amd-pstate driver to avoid cases where call paths end up calling the same writes multiple times and needlessly caching variables through code reorganization, locking overhaul and tracing adjustments (Mario Limonciello, Dhananjay Ugwekar) - Make it possible to avoid enabling capacity-aware scheduling (CAS) in the intel_pstate driver and relocate a check for out-of-band (OOB) platform handling in it to make it detect OOB before checking HWP availability (Rafael Wysocki) - Fix dbs_update() to avoid inadvertent conversions of negative integer values to unsigned int which causes CPU frequency selection to be inaccurate in some cases when the "conservative" cpufreq governor is in use (Jie Zhan) - Update the handling of the most recent idle intervals in the menu cpuidle governor to prevent useful information from being discarded by it in some cases and improve the prediction accuracy (Rafael Wysocki) - Make it possible to tell the intel_idle driver to ignore its built-in table of idle states for the given processor, clean up the handling of auto-demotion disabling on Baytrail and Cherrytrail chips in it, and update its MAINTAINERS entry (David Arcari, Artem Bityutskiy, Rafael Wysocki) - Make some cpuidle drivers use for_each_present_cpu() instead of for_each_possible_cpu() during initialization to avoid issues occurring when nosmp or maxcpus=0 are used (Jacky Bai) - Clean up the Energy Model handling code somewhat (Rafael Wysocki) - Use kfree_rcu() to simplify the handling of runtime Energy Model updates (Li RongQing) - Add an entry for the Energy Model framework to MAINTAINERS as properly maintained (Lukasz Luba) - Address RCU-related sparse warnings in the Energy Model code (Rafael Wysocki) - Remove ENERGY_MODEL dependency on SMP and allow it to be selected when DEVFREQ is set without CPUFREQ so it can be used on a wider range of systems (Jeson Gao) - Unify error handling during runtime suspend and runtime resume in the core to help drivers to implement more consistent runtime PM error handling (Rafael Wysocki) - Drop a redundant check from pm_runtime_force_resume() and rearrange documentation related to __pm_runtime_disable() (Rafael Wysocki) - Rework the handling of the "smart suspend" driver flag in the PM core to avoid issues hat may occur when drivers using it depend on some other drivers and clean up the related PM core code (Rafael Wysocki, Colin Ian King) - Fix the handling of devices with the power.direct_complete flag set if device_suspend() returns an error for at least one device to avoid situations in which some of them may not be resumed (Rafael Wysocki) - Use mutex_trylock() in hibernate_compressor_param_set() to avoid a possible deadlock that may occur if the "compressor" hibernation module parameter is accessed during the registration of a new ieee80211 device (Lizhi Xu) - Suppress sleeping parent warning in device_pm_add() in the case when new children are added under a device with the power.direct_complete set after it has been processed by device_resume() (Xu Yang) - Remove needless return in three void functions related to system wakeup (Zijun Hu) - Replace deprecated kmap_atomic() with kmap_local_page() in the hibernation core code (David Reaver) - Remove unused helper functions related to system sleep (David Alan Gilbert) - Clean up s2idle_enter() so it does not lock and unlock CPU offline in vain and update comments in it (Ulf Hansson) - Clean up broken white space in dpm_wait_for_children() (Geert Uytterhoeven) - Update the cpupower utility to fix lib version-ing in it and memory leaks in error legs, remove hard-coded values, and implement CPU physical core querying (Thomas Renninger, John B. Wyatt IV, Shuah Khan, Yiwei Lin, Zhongqiu Han)" * tag 'pm-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (139 commits) PM: sleep: Fix bit masking operation dt-bindings: cpufreq: cpufreq-qcom-hw: Narrow properties on SDX75, SA8775p and SM8650 dt-bindings: cpufreq: cpufreq-qcom-hw: Drop redundant minItems:1 dt-bindings: cpufreq: cpufreq-qcom-hw: Add missing constraint for interrupt-names dt-bindings: cpufreq: cpufreq-qcom-hw: Add QCS8300 compatible cpufreq: Init cpufreq only for present CPUs PM: sleep: Fix handling devices with direct_complete set on errors cpuidle: Init cpuidle only for present CPUs PM: clk: Remove unused pm_clk_remove() PM: sleep: core: Fix indentation in dpm_wait_for_children() PM: s2idle: Extend comment in s2idle_enter() PM: s2idle: Drop redundant locks when entering s2idle PM: sleep: Remove unused pm_generic_ wrappers cpufreq: tegra186: Share policy per cluster cpupower: Make lib versioning scheme more obvious and fix version link PM: EM: Rework the depends on for CONFIG_ENERGY_MODEL PM: EM: Address RCU-related sparse warnings cpupower: Implement CPU physical core querying pm: cpupower: remove hard-coded topology depth values pm: cpupower: Fix cmd_monitor() error legs to free cpu_topology ...
2025-03-24Merge branch 'pm-cpuidle'Rafael J. Wysocki
Merge cpuidle updates for 6.15-rc5, including a menu governor update that is reported to improve some benchmark results quite significantly: - Update the handling of the most recent idle intervals in the menu cpuidle governor to prevent useful information from being discarded by it in some cases and improve the prediction accuracy (Rafael Wysocki). - Make it possible to tell the intel_idle driver to ignore its built-in table of idle states for the given processor, clean up the handling of auto-demotion disabling on Baytrail and Cherrytrail chips in it, and update its MAINTAINERS entry (David Arcari, Artem Bityutskiy, Rafael Wysocki). - Make some cpuidle drivers use for_each_present_cpu() instead of for_each_possible_cpu() during initialization to avoid issues occurring when nosmp or maxcpus=0 are used (Jacky Bai). * pm-cpuidle: cpuidle: Init cpuidle only for present CPUs cpuidle: intel_idle: Update MAINTAINERS intel_idle: introduce 'no_native' module parameter cpuidle: menu: Update documentation after get_typical_interval() changes cpuidle: menu: Avoid discarding useful information cpuidle: menu: Eliminate outliers on both ends of the sample set cpuidle: menu: Tweak threshold use in get_typical_interval() cpuidle: menu: Use one loop for average and variance computations cpuidle: menu: Drop a redundant local variable intel_idle: clean up BYT/CHT auto demotion disable
2025-02-25Merge branch 'cpuidle-menu'Rafael J. Wysocki
This work had been triggered by a report that commit 0611a640e60a ("eventpoll: prefer kfree_rcu() in __ep_remove()") had caused the critical-jOPS metric of the SPECjbb 2015 benchmark [1] to drop by around 50% even though it generally reduced kernel overhead. Indeed, it was found during further investigation that the total interrupt rate while running the SPECjbb workload had fallen as a result of that commit by 55% and the local timer interrupt rate had fallen by almost 80%. That turned out to cause the menu cpuidle governor to select the deepest idle state supplied by the cpuidle driver (intel_idle) much more often which added significantly more idle state latency to the workload and that led to the decrease of the critical-jOPS score. Interestingly enough, this problem was not visible when the teo cpuidle governor was used instead of menu, so it appeared to be specific to the latter. CPU wakeup event statistics collected while running the workload indicated that the menu governor was effectively ignoring non- timer wakeup information and all of its idle state selection decisions appeared to be based on timer wakeups only. Thus, it appeared that the reduction of the local timer interrupt rate caused the governor to predict a idle duration much more often while running the workload and the deepest idle state was selected significantly more often as a result of that. A subsequent inspection of the get_typical_interval() function in the menu governor indicated that it might return UINT_MAX too often which then caused the governor's decisions to be based entirely on information related to timers. Generally speaking, UINT_MAX is returned by get_typical_interval() if it cannot make a prediction based on the most recent idle intervals data with sufficiently high confidence, but at least in some cases this means that useful information is not taken into account at all which may lead to significant idle state selection mistakes. Moreover, this is not really unlikely to happen. One issue with get_typical_interval() is that, when it eliminates outliers from the sample set in an attempt to reduce the standard deviation (and so improve the prediction confidence), it does that by dropping high-end samples only, while samples at the low end of the set are retained. However, the samples at the low end very well may be the outliers and they should be eliminated from the sample set instead of the high-end samples. Accordingly, the likelihood of making a meaningful idle duration prediction can be improved by making it also eliminate low-end samples if they are farther from the average than high-end samples. Another issue is that get_typical_interval() gives up after eliminating 1/4 of the samples if the standard deviation is still not as low as desired (within 1/6 of the average or within 20 us if the average is close to 0), but the remaining samples in the set still represent useful information at that point and discarding them altogether may lead to suboptimal idle state selection. For instance, the largest idle duration value in the get_typical_interval() data set is the maximum idle duration observed recently and it is likely that the upcoming idle duration will not exceed it. Therefore, in the absence of a better choice, this value can be used as an upper bound on the target residency of the idle state to select. * cpuidle-menu: cpuidle: menu: Update documentation after get_typical_interval() changes cpuidle: menu: Avoid discarding useful information cpuidle: menu: Eliminate outliers on both ends of the sample set cpuidle: menu: Tweak threshold use in get_typical_interval() cpuidle: menu: Use one loop for average and variance computations cpuidle: menu: Drop a redundant local variable
2025-02-25intel_idle: introduce 'no_native' module parameterDavid Arcari
Since commit 18734958e9bf ("intel_idle: Use ACPI _CST for processor models without C-state tables") the intel_idle driver has had the ability to use the ACPI _CST to populate C-states when the processor model is not recognized. However, even when the processor model is recognized (native mode) there are cases where it is useful to make the driver ignore the per-CPU idle states in lieu of ACPI C-states (such as specific application performance). Add a new 'no_native' module parameter to provide this functionality. Signed-off-by: David Arcari <darcari@redhat.com> Link: https://patch.msgid.link/20250220151120.1131122-1-darcari@redhat.com Reviewed-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> [ rjw: Spell CPU in capitals ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-02-25cpuidle: menu: Update documentation after get_typical_interval() changesRafael J. Wysocki
The documentation of the menu cpuidle governor needs to be updated to match the code behavior after some changes made recently. No functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Christian Loehle <christian.loehle@arm.com> Link: https://patch.msgid.link/4998484.31r3eYUQgx@rjwysocki.net [ rjw: More specific subject, two typos fixed in the changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-02-18cpufreq: intel_pstate: Make it possible to avoid enabling CASRafael J. Wysocki
Capacity-aware scheduling (CAS) is enabled by default by intel_pstate on hybrid systems without SMT, but in some usage scenarios it may be more attractive to place tasks for maximum CPU performance regardless of the extra cost in terms of energy, which is the case on such systems when CAS is not enabled, so introduce a command line option to forbid intel_pstate to enable CAS. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by:Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Link: https://patch.msgid.link/2781262.mvXUDI8C0e@rjwysocki.net
2025-02-17cpufreq: Introduce an optional cpuinfo_avg_freq sysfs entryBeata Michalska
Currently the CPUFreq core exposes two sysfs attributes that can be used to query current frequency of a given CPU(s): namely cpuinfo_cur_freq and scaling_cur_freq. Both provide slightly different view on the subject and they do come with their own drawbacks. cpuinfo_cur_freq provides higher precision though at a cost of being rather expensive. Moreover, the information retrieved via this attribute is somewhat short lived as frequency can change at any point of time making it difficult to reason from. scaling_cur_freq, on the other hand, tends to be less accurate but then the actual level of precision (and source of information) varies between architectures making it a bit ambiguous. The new attribute, cpuinfo_avg_freq, is intended to provide more stable, distinct interface, exposing an average frequency of a given CPU(s), as reported by the hardware, over a time frame spanning no more than a few milliseconds. As it requires appropriate hardware support, this interface is optional. Note that under the hood, the new attribute relies on the information provided by arch_freq_get_on_cpu, which, up to this point, has been feeding data for scaling_cur_freq attribute, being the source of ambiguity when it comes to interpretation. This has been amended by restoring the intended behavior for scaling_cur_freq, with a new dedicated config option to maintain status quo for those, who may need it. CC: Jonathan Corbet <corbet@lwn.net> CC: Thomas Gleixner <tglx@linutronix.de> CC: Ingo Molnar <mingo@redhat.com> CC: Borislav Petkov <bp@alien8.de> CC: Dave Hansen <dave.hansen@linux.intel.com> CC: H. Peter Anvin <hpa@zytor.com> CC: Phil Auld <pauld@redhat.com> CC: x86@kernel.org CC: linux-doc@vger.kernel.org Signed-off-by: Beata Michalska <beata.michalska@arm.com> Reviewed-by: Prasanna Kumar T S M <ptsm@linux.microsoft.com> Reviewed-by: Sumit Gupta <sumitg@nvidia.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Rafael J. Wysocki <rafael@kernel.org> Link: https://lore.kernel.org/r/20250131162439.3843071-3-beata.michalska@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-01-13cpuidle: menu: Update documentation after previous changesRafael J. Wysocki
After commit 38f83090f515 ("cpuidle: menu: Remove iowait influence") and other previous changes, the description of the menu governor in the documentation does not match the code any more, so update it as appropriate. Fixes: 38f83090f515 ("cpuidle: menu: Remove iowait influence") Fixes: 5484e31bbbff ("cpuidle: menu: Skip tick_nohz_get_sleep_length() call in some cases") Reported-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Christian Loehle <christian.loehle@arm.com> Link: https://patch.msgid.link/12589281.O9o76ZdvQC@rjwysocki.net
2024-12-10cpufreq/amd-pstate: Store the boost numerator as highest perf againMario Limonciello
commit ad4caad58d91d ("cpufreq: amd-pstate: Merge amd_pstate_highest_perf_set() into amd_get_boost_ratio_numerator()") changed the semantics for highest perf and commit 18d9b52271213 ("cpufreq/amd-pstate: Use nominal perf for limits when boost is disabled") worked around those semantic changes. This however is a confusing result and furthermore makes it awkward to change frequency limits and boost due to the scaling differences. Restore the boost numerator to highest perf again. Suggested-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@amd.com> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Fixes: ad4caad58d91 ("cpufreq: amd-pstate: Merge amd_pstate_highest_perf_set() into amd_get_boost_ratio_numerator()") Link: https://lore.kernel.org/r/20241209185248.16301-2-mario.limonciello@amd.com Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-10-21cpufreq: docs: Reflect latency changes in docsChristian Loehle
There were two changes related to transition latency recently. Namely commit e13aa799c2a6 ("cpufreq: Change default transition delay to 2ms") and commit 37c6dccd6837 ("cpufreq: Remove LATENCY_MULTIPLIER"). Both changed the defaults / maximums so let the documentation reflect that. Signed-off-by: Christian Loehle <christian.loehle@arm.com> Link: https://patch.msgid.link/46853b6e-bad5-4ace-9b23-ff157f234ae3@arm.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-09-19Merge tag 'platform-drivers-x86-v6.12-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86 Pull x86 platform drivers updates from Hans de Goede: - asus-wmi: Add support for vivobook fan profiles - dell-laptop: Add knobs to change battery charge settings - lg-laptop: Add operation region support - intel-uncore-freq: Add support for efficiency latency control - intel/ifs: Add SBAF test support - intel/pmc: Ignore all LTRs during suspend - platform/surface: Support for arm64 based Surface devices - wmi: Pass event data directly to legacy notify handlers - x86/platform/geode: switch GPIO buttons and LEDs to software properties - bunch of small cleanups, fixes, hw-id additions, etc. * tag 'platform-drivers-x86-v6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (65 commits) MAINTAINERS: adjust file entry in INTEL MID PLATFORM platform/x86: x86-android-tablets: Adjust Xiaomi Pad 2 bottom bezel touch buttons LED platform/mellanox: mlxbf-pmc: fix lockdep warning platform/x86/amd: pmf: Add quirk for TUF Gaming A14 platform/x86: touchscreen_dmi: add nanote-next quirk platform/x86: asus-wmi: don't fail if platform_profile already registered platform/x86: asus-wmi: add debug print in more key places platform/x86: intel_scu_wdt: Move intel_scu_wdt.h to x86 subfolder platform/x86: intel_scu_ipc: Move intel_scu_ipc.h out of arch/x86/include/asm MAINTAINERS: Add Intel MID section platform/x86: panasonic-laptop: Add support for programmable buttons platform/olpc: Remove redundant null pointer checks in olpc_ec_setup_debugfs() platform/x86: intel/pmc: Ignore all LTRs during suspend platform/x86: wmi: Call both legacy and WMI driver notify handlers platform/x86: wmi: Merge get_event_data() with wmi_get_notify_data() platform/x86: wmi: Remove wmi_get_event_data() platform/x86: wmi: Pass event data directly to legacy notify handlers platform/x86: thinkpad_acpi: Fix uninitialized symbol 's' warning platform/x86: x86-android-tablets: Fix spelling in the comments platform/x86: ideapad-laptop: Make the scope_guard() clear of its scope ...
2024-09-11amd-pstate: Add missing documentation for `amd_pstate_prefcore_ranking`Mario Limonciello
`amd_pstate_prefcore_ranking` reflects the dynamic rankings of a CPU core based on platform conditions. Explicitly include it in the documentation. Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-09-11cpufreq: amd-pstate: Add documentation for `amd_pstate_hw_prefcore`Mario Limonciello
Explain that the sysfs file represents both preferred core being enabled by the user and supported by the hardware. Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-09-11cpufreq: amd-pstate: Merge amd_pstate_highest_perf_set() into ↵Mario Limonciello
amd_get_boost_ratio_numerator() The special case in amd_pstate_highest_perf_set() is the value used for calculating the boost numerator. Merge this into amd_get_boost_ratio_numerator() and then use that to calculate boost ratio. This allows dropping more special casing of the highest perf value. Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-09-04Documentation: admin-guide: pm: Add efficiency vs. latency tradeoff to ↵Tero Kristo
uncore documentation Added documentation about the functionality of efficiency vs. latency tradeoff control in intel Xeon processors, and how this is configured via sysfs. Signed-off-by: Tero Kristo <tero.kristo@linux.intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20240828153657.1296410-2-tero.kristo@linux.intel.com Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2024-07-02cpufreq: docs: Add missing scaling_available_frequencies descriptionRaphael Gallais-Pou
Add a description of the scaling_available_frequencies attribute in sysfs to the documentation. Signed-off-by: Raphael Gallais-Pou <rgallaispou@gmail.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Link: https://patch.msgid.link/20240701171040.369030-1-rgallaispou@gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-06-26Documentation: cpufreq: amd-pstate: update doc for Per CPU boost control methodPerry Yuan
Updates the documentation in `amd-pstate.rst` to include information about the per CPU boost control feature. Users can now enable or disable the Core Performance Boost (CPB) feature on individual CPUs using the `boost` sysfs attribute. Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Signed-off-by: Perry Yuan <perry.yuan@amd.com> Co-developed-by: Mario Limonciello <mario.limonciello@amd.com> Link: https://lore.kernel.org/r/20240626042733.3747-5-mario.limonciello@amd.com Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-06-20Documentation: PM: amd-pstate: add guided mode to the Operation modePerry Yuan
the guided mode is also supported, so the operation mode should include that mode as well. Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Perry Yuan <perry.yuan@amd.com> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Link: https://lore.kernel.org/r/a61d825ef71f6aacc8f1624fe9fb982b8446b5a7.1718811234.git.perry.yuan@amd.com Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-02-12Documentation: PM: amd-pstate: Fix section title underlineMeng Li
Title under line too short Signed-off-by: Meng Li <li.meng@amd.com> [ rjw: Subject edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-01-31Documentation: amd-pstate: introduce amd-pstate preferred coreMeng Li
Introduce amd-pstate preferred core. check preferred core state set by the kernel parameter: $ cat /sys/devices/system/cpu/amd-pstate/prefcore Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Perry Yuan <perry.yuan@amd.com> Signed-off-by: Meng Li <li.meng@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-01-10Documentation: admin-guide: PM: Fix two typosErwan Velu
Fix two typos in the admin-guide: - a missing e in "reference_perf" in cppc_sysfs.rst. - the amd_pstate sysfs path uses a dash instead of an underscore. Signed-off-by: Erwan Velu <e.velu@criteo.com> [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-10-07intel_idle: Add ibrs_off module parameter to force-disable IBRSWaiman Long
Commit bf5835bcdb96 ("intel_idle: Disable IBRS during long idle") disables IBRS when the cstate is 6 or lower. However, there are some use cases where a customer may want to use max_cstate=1 to lower latency. Such use cases will suffer from the performance degradation caused by the enabling of IBRS in the sibling idle thread. Add a "ibrs_off" module parameter to force disable IBRS and the CPUIDLE_FLAG_IRQ_ENABLE flag if set. In the case of a Skylake server with max_cstate=1, this new ibrs_off option will likely increase the IRQ response latency as IRQ will now be disabled. When running SPECjbb2015 with cstates set to C1 on a Skylake system. First test when the kernel is booted with: "intel_idle.ibrs_off": max-jOPS = 117828, critical-jOPS = 66047 Then retest when the kernel is booted without the "intel_idle.ibrs_off" added: max-jOPS = 116408, critical-jOPS = 58958 That means booting with "intel_idle.ibrs_off" improves performance by: max-jOPS: +1.2%, which could be considered noise range. critical-jOPS: +12%, which is definitely a solid improvement. The admin-guide/pm/intel_idle.rst file is updated to add a description about the new "ibrs_off" module parameter. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20230727184600.26768-5-longman@redhat.com
2023-05-09platform/x86/intel-uncore-freq: Support for cluster level controlsSrinivas Pandruvada
An SoC can contain multiple power domains with individual or collection of mesh partitions. This partition is called fabric cluster. Certain type of meshes will need to run at the same frequency, they will be placed in the same fabric cluster. Benefit of fabric cluster is that it offers a scalable mechanism to deal with partitioned fabrics in a SoC. The current sysfs interface supports control at package and die level. This interface is not enough to support more granular control at fabric cluster level. SoCs with the support of TPMI (Topology Aware Register and PM Capsule Interface), can have multiple power domains. Each power domain can contain one or more fabric clusters. To support such granular controls, enhance uncore common to optionally create new directories to provide controls at fabric cluster level. It is also important to have flexibility to change granularity for future version of SoCs. If the directory name contains scope like: "package_*_die_*_power_domain_*_cluster_*", then this is not expandable. The cpufreq policies also have different scopes. There the scope of the policy (affected_cpus) specified by attributes inside each policy. So, follow the same model for uncore frequency scaling sysfs as: "sys/devices/system/cpu/cpufreq/policy*" Allow client drivers to optionally support granular control for each fabric cluster. Here, the directory name will be "uncore" suffixed with an unique instance number. For example: uncore00, uncore01 etc. Attributes in the directory identify package id, power domain and fabric cluster id. This interface is expandable even if some new level of granularity is introduced. A new sysfs attribute can identify new level. For compatibility with the existing sysfs and provide easy way to set limits for each fabric cluster in the package/die, the existing control at package/die levels are still provided. For majority of users, this is an easy approach. For example: On a single package/die system, with three power domains and one fabric cluster per power domain: $tree -L 2 /sys/devices/system/cpu/intel_uncore_frequency/ /sys/devices/system/cpu/intel_uncore_frequency/ ├── package_00_die_00 │   ├── current_freq_khz │   ├── initial_max_freq_khz │   ├── initial_min_freq_khz │   ├── max_freq_khz │   └── min_freq_khz ├── uncore00 │   ├── current_freq_khz │   ├── domain_id │   ├── fabric_cluster_id │   ├── initial_max_freq_khz │   ├── initial_min_freq_khz │   ├── max_freq_khz │   ├── min_freq_khz │   └── package_id ├── uncore01 │   ├── current_freq_khz │   ├── domain_id │   ├── fabric_cluster_id │   ├── initial_max_freq_khz │   ├── initial_min_freq_khz │   ├── max_freq_khz │   ├── min_freq_khz │   └── package_id └── uncore02 ├── current_freq_khz ├── domain_id ├── fabric_cluster_id ├── initial_max_freq_khz ├── initial_min_freq_khz ├── max_freq_khz ├── min_freq_khz └── package_id The attribute for cluster id is "fabric_cluster_id" instead of just "cluster_id" is to avoid confusion with usage of term clusters in other part of the Linux kernel. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Reviewed-by: Zhang Rui <rui.zhang@intel.com> Tested-by: Wendy Wang <wendy.wang@intel.com> Link: https://lore.kernel.org/r/20230418171340.681662-3-srinivas.pandruvada@linux.intel.com Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2023-03-17Documentation: cpufreq: amd-pstate: Update amd_pstate status sysfs for guidedWyes Karny
Update amd_pstate status sysfs for guided mode. Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Signed-off-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-02-22Merge tag 'docs-6.3' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It has been a moderately calm cycle for documentation; the significant changes include: - Some significant additions to the memory-management documentation - Some improvements to navigation in the HTML-rendered docs - More Spanish and Chinese translations ... and the usual set of typo fixes and such" * tag 'docs-6.3' of git://git.lwn.net/linux: (68 commits) Documentation/watchdog/hpwdt: Fix Format Documentation/watchdog/hpwdt: Fix Reference Documentation: core-api: padata: correct spelling docs/mm: Physical Memory: correct spelling in reference to CONFIG_PAGE_EXTENSION docs: Use HTML comments for the kernel-toc SPDX line docs: Add more information to the HTML sidebar Documentation: KVM: Update AMD memory encryption link printk: Document that CONFIG_BOOT_PRINTK_DELAY required for boot_delay= Documentation: userspace-api: correct spelling Documentation: sparc: correct spelling Documentation: driver-api: correct spelling Documentation: admin-guide: correct spelling docs: add workload-tracing document to admin-guide docs/admin-guide/mm: remove useless markup docs/mm: remove useless markup docs/mm: Physical Memory: remove useless markup docs/sp_SP: Add process magic-number translation docs: ftrace: always use canonical ftrace path Doc/damon: fix the data path error dma-buf: Add "dma-buf" to title of documentation ...
2023-02-15Documentation: amd-pstate: disambiguate user space sectionsBagas Sanjaya
kernel test robot reported htmldocs warning: Documentation/admin-guide/pm/amd-pstate.rst:343: WARNING: duplicate label admin-guide/pm/amd-pstate:user space interface in ``sysfs``, other instance in Documentation/admin-guide/pm/amd-pstate.rst The documentation contains two sections with the same "User Space Interface in ``sysfs``" title. The first one deals with per-policy sysfs and the second one is about general attributes (currently only global attributes are documented). Disambiguate title text of both sections to fix the warning. Link: https://lore.kernel.org/linux-doc/202302151041.0SWs1RHK-lkp@intel.com/ Fixes: b9e6a2d47b2565 ("Documentation: amd-pstate: introduce new global sysfs attributes") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Acked-by: Huang Rui <ray.huang@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-02-03Documentation: amd-pstate: introduce new global sysfs attributesPerry Yuan
The amd-pstate driver supports switching working modes at runtime. Users can view and change modes by interacting with the "status" sysfs attribute. 1) check driver mode: $ cat /sys/devices/system/cpu/amd-pstate/status 2) switch mode: `# echo "passive" | sudo tee /sys/devices/system/cpu/amd-pstate/status` or `# echo "active" | sudo tee /sys/devices/system/cpu/amd-pstate/status` Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Tested-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Perry Yuan <perry.yuan@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-02-03Documentation: amd-pstate: add amd pstate driver mode introductionPerry Yuan
The amd-pstate driver has two operation modes supported: * CPPC Autonomous (active) mode * CPPC non-autonomous (passive) mode. active mode and passive mode can be chosen by different kernel parameters. Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Tested-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-02-03Documentation: amd-pstate: add EPP profiles introductionPerry Yuan
The amd-pstate driver supports a feature called energy performance preference (EPP). Add information to the documentation to explain how users can interact with the sysfs files for this feature. 1) See all EPP profiles $ sudo cat /sys/devices/system/cpu/cpu0/cpufreq/energy_performance_available_preferences default performance balance_performance balance_power power 2) Check current EPP profile $ sudo cat /sys/devices/system/cpu/cpu0/cpufreq/energy_performance_preference performance 3) Set new EPP profile $ sudo bash -c "echo power > /sys/devices/system/cpu/cpu0/cpufreq/energy_performance_preference" Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Tested-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-02-02Documentation: admin-guide: correct spellingRandy Dunlap
Correct spelling problems for Documentation/admin-guide/ as reported by codespell. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com> Cc: Tejun Heo <tj@kernel.org> Cc: Zefan Li <lizefan.x@bytedance.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: cgroups@vger.kernel.org Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@kernel.org> Cc: dm-devel@redhat.com Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: linux-media@vger.kernel.org Cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230129231053.20863-2-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-01-31docs: ftrace: always use canonical ftrace pathRoss Zwisler
The canonical location for the tracefs filesystem is at /sys/kernel/tracing. But, from Documentation/trace/ftrace.rst: Before 4.1, all ftrace tracing control files were within the debugfs file system, which is typically located at /sys/kernel/debug/tracing. For backward compatibility, when mounting the debugfs file system, the tracefs file system will be automatically mounted at: /sys/kernel/debug/tracing Many parts of Documentation still reference this older debugfs path, so let's update them to avoid confusion. Signed-off-by: Ross Zwisler <zwisler@google.com> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20230125213251.2013791-1-zwisler@google.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-12-12Merge tag 'linux-kselftest-next-6.2-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull Kselftest updates from Shuah Khan: "Several fixes and enhancements to existing tests and a few new tests: - add new amd-pstate tests and fix and enhance existing ones - add new watchdog tests and enhance existing ones to improve coverage - fixes to ftrace, splice_read, rtc, and efivars tests - fixes to handle egrep obsolescence in the latest grep release - miscellaneous spelling and SPDX fixes" * tag 'linux-kselftest-next-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (24 commits) selftests/ftrace: Use long for synthetic event probe test selftests/tpm2: Split async tests call to separate shell script runner selftests: splice_read: Fix sysfs read cases selftests: ftrace: Use "grep -E" instead of "egrep" selftests: gpio: Use "grep -E" instead of "egrep" selftests: kselftest_deps: Use "grep -E" instead of "egrep" selftests/efivarfs: Add checking of the test return value cpufreq: amd-pstate: fix spdxcheck warnings for amd-pstate-ut.c selftests: rtc: skip when RTC is not present selftests/ftrace: event_triggers: wait longer for test_event_enable selftests/vDSO: Add riscv getcpu & gettimeofday test Documentation: amd-pstate: Add tbench and gitsource test introduction selftests: amd-pstate: Trigger gitsource benchmark and test cpus selftests: amd-pstate: Trigger tbench benchmark and test cpus selftests: amd-pstate: Split basic.sh into run.sh and basic.sh. selftests: amd-pstate: Rename amd-pstate-ut.sh to basic.sh. selftests/ftrace: Convert tracer tests to use 'requires' to specify program dependency selftests/ftrace: Add check for ping command for trigger tests selftests/watchdog: Fix spelling mistake "Temeprature" -> "Temperature" selftests/watchdog: add test for WDIOC_GETTEMP ...
2022-11-22Documentation: amd-pstate: add driver working mode introductionPerry Yuan
Introduce the `amd_pstate` driver new working mode with `amd_pstate=passive` added to kernel command line. If there is no passive mode enabled by user, amd_pstate driver will be disabled by default for now. Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Tested-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-11-01Documentation: amd-pstate: Add tbench and gitsource test introductionMeng Li
Introduce tbench and gitsource test cases design and implementation. Monitor cpus changes about performance and power consumption etc. Signed-off-by: Meng Li <li.meng@amd.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-05Documentation: amd-pstate: Add unit test introductionMeng Li
Introduce the AMD P-State unit test module design and implementation. It also talks about kselftest and how to use. Signed-off-by: Meng Li <li.meng@amd.com> Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-08-01Merge tag 'x86_cpu_for_v6.0_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu updates from Borislav Petkov: - Remove the vendor check when selecting MWAIT as the default idle state - Respect idle=nomwait when supplied on the kernel cmdline - Two small cleanups * tag 'x86_cpu_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Use MSR_IA32_MISC_ENABLE constants x86: Fix comment for X86_FEATURE_ZEN x86: Remove vendor checks from prefer_mwait_c1_over_halt x86: Handle idle=nomwait cmdline properly for x86_idle
2022-06-08x86: Handle idle=nomwait cmdline properly for x86_idleWyes Karny
When kernel is booted with idle=nomwait do not use MWAIT as the default idle state. If the user boots the kernel with idle=nomwait, it is a clear direction to not use mwait as the default idle state. However, the current code does not take this into consideration while selecting the default idle state on x86. Fix it by checking for the idle=nomwait boot option in prefer_mwait_c1_over_halt(). Also update the documentation around idle=nomwait appropriately. [ dhansen: tweak commit message ] Signed-off-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Tested-by: Zhang Rui <rui.zhang@intel.com> Link: https://lkml.kernel.org/r/fdc2dc2d0a1bc21c2f53d989ea2d2ee3ccbc0dbe.1654538381.git-series.wyes.karny@amd.com
2022-05-25Documentation: admin-guide: PM: Add Out of Band modeSrinivas Pandruvada
Update documentation for using the tool to support performance level change via OOB (Out of Band) interface. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-29Merge branch 'pm-docs'Rafael J. Wysocki
Merge additional power management documentation udates for 5.18-rc1: - Add Intel uncore frequency scaling documentation file to its MAINTAINERS entry (Srinivas Pandruvada). - Clean up the AMD P-state driver documentation (Jan Engelhardt). * pm-docs: Documentation: amd-pstate: grammar and sentence structure updates MAINTAINERS: Add additional file to uncore frequency control
2022-03-25Documentation: amd-pstate: grammar and sentence structure updatesJan Engelhardt
Signed-off-by: Jan Engelhardt <jengelh@inai.de> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-18Merge branch 'pm-tools'Rafael J. Wysocki
Merge power management utilities changes for 5.18-rc1: - Add tracer tool for the amd-pstate driver (Jinzhou Su). - Fix PC6 displaying in turbostat on some systems (Artem Bityutskiy). - Add AMD P-State support to the cpupower utility (Huang Rui). * pm-tools: Documentation: amd-pstate: add tracer tool introduction tools/power/x86/amd_pstate_tracer: Add tracer tool for AMD P-state tools/power/x86/intel_pstate_tracer: make tracer as a module cpufreq: amd-pstate: Add more tracepoint for AMD P-State module turbostat: fix PC6 displaying on some systems cpupower: Add "perf" option to print AMD P-State information cpupower: Add function to print AMD P-State performance capabilities cpupower: Move print_speed function into misc helper cpupower: Enable boost state support for AMD P-State module cpupower: Add AMD P-State sysfs definition and access helper cpupower: Introduce ACPI CPPC library cpupower: Add the function to get the sysfs value from specific table cpupower: Initial AMD P-State capability cpupower: Add the function to check AMD P-State enabled cpupower: Add AMD P-State capability flag tools/power/cpupower/{ToDo => TODO}: Rename the todo file tools: cpupower: fix typo in cpupower-idle-set(1) manpage
2022-03-09Documentation: amd-pstate: add tracer tool introductionJinzhou Su
Add amd pstate tracer tool introduction Signed-off-by: Jinzhou Su <Jinzhou.Su@amd.com> Reviewed-by: Huang Rui <ray.huang@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-01Documentation: admin-guide: pm: Document uncore frequency scalingSrinivas Pandruvada
Added documentation to configure uncore frequency limits in Intel Xeon processors. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> [ rjw: Clean up the document wording ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-30Documentation: amd-pstate: Add AMD P-State driver introductionHuang Rui
Introduce the AMD P-State driver design and implementation. Signed-off-by: Huang Rui <ray.huang@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-29Merge tag 'pm-5.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These add hybrid processors support to the intel_pstate driver and make it work with more processor models when HWP is disabled, make the intel_idle driver use special C6 idle state paremeters when package C-states are disabled, add cooling support to the tegra30 devfreq driver, rework the TEO (timer events oriented) cpuidle governor, extend the OPP (operating performance points) framework to use the required-opps DT property in more cases, fix some issues and clean up a number of assorted pieces of code. Specifics: - Make intel_pstate support hybrid processors using abstract performance units in the HWP interface (Rafael Wysocki). - Add Icelake servers and Cometlake support in no-HWP mode to intel_pstate (Giovanni Gherdovich). - Make cpufreq_online() error path be consistent with the CPU device removal path in cpufreq (Rafael Wysocki). - Clean up 3 cpufreq drivers and the statistics code (Hailong Liu, Randy Dunlap, Shaokun Zhang). - Make intel_idle use special idle state parameters for C6 when package C-states are disabled (Chen Yu). - Rework the TEO (timer events oriented) cpuidle governor to address some theoretical shortcomings in it (Rafael Wysocki). - Drop unneeded semicolon from the TEO governor (Wan Jiabing). - Modify the runtime PM framework to accept unassigned suspend and resume callback pointers (Ulf Hansson). - Improve pm_runtime_get_sync() documentation (Krzysztof Kozlowski). - Improve device performance states support in the generic power domains (genpd) framework (Ulf Hansson). - Fix some documentation issues in genpd (Yang Yingliang). - Make the operating performance points (OPP) framework use the required-opps DT property in use cases that are not related to genpd (Hsin-Yi Wang). - Make lazy_link_required_opp_table() use list_del_init instead of list_del/INIT_LIST_HEAD (Yang Yingliang). - Simplify wake IRQs handling in the core system-wide sleep support code and clean up some coding style inconsistencies in it (Tian Tao, Zhen Lei). - Add cooling support to the tegra30 devfreq driver and improve its DT bindings (Dmitry Osipenko). - Fix some assorted issues in the devfreq core and drivers (Chanwoo Choi, Dong Aisheng, YueHaibing)" * tag 'pm-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (39 commits) PM / devfreq: passive: Fix get_target_freq when not using required-opp cpufreq: Make cpufreq_online() call driver->offline() on errors opp: Allow required-opps to be used for non genpd use cases cpuidle: teo: remove unneeded semicolon in teo_select() dt-bindings: devfreq: tegra30-actmon: Add cooling-cells dt-bindings: devfreq: tegra30-actmon: Convert to schema PM / devfreq: userspace: Use DEVICE_ATTR_RW macro PM: runtime: Clarify documentation when callbacks are unassigned PM: runtime: Allow unassigned ->runtime_suspend|resume callbacks PM: runtime: Improve path in rpm_idle() when no callback PM: hibernate: remove leading spaces before tabs PM: sleep: remove trailing spaces and tabs PM: domains: Drop/restore performance state votes for devices at runtime PM PM: domains: Return early if perf state is already set for the device PM: domains: Split code in dev_pm_genpd_set_performance_state() cpuidle: teo: Use kerneldoc documentation in admin-guide cpuidle: teo: Rework most recent idle duration values treatment cpuidle: teo: Change the main idle state selection logic cpuidle: teo: Cosmetic modification of teo_select() cpuidle: teo: Cosmetic modifications of teo_update() ...