kernel/git/stable/linux-stable.git/drivers/cpuidle, branch linux-6.17.y

cpuidle: Fail cpuidle device registration if there is one already

2025-11-13T20:36:52+00:00

[ Upstream commit 7b1b7961170e4fcad488755e5ffaaaf9bd527e8f ] Refuse to register a cpuidle device if the given CPU has a cpuidle device already and print a message regarding it. Without this, an attempt to register a new cpuidle device without unregistering the existing one leads to the removal of the existing cpuidle device without removing its sysfs interface. Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

cpuidle: governors: menu: Select polling state in some more cases

2025-11-13T20:36:45+00:00

[ Upstream commit db86f55bf81a3a297be05ee8775ae9a8c6e3a599 ] A throughput regression of 11% introduced by commit 779b1a1cb13a ("cpuidle: governors: menu: Avoid selecting states with too much latency") has been reported and it is related to the case when the menu governor checks if selecting a proper idle state instead of a polling one makes sense. In particular, it is questionable to do so if the exit latency of the idle state in question exceeds the predicted idle duration, so add a check for that, which is sufficient to make the reported regression go away, and update the related code comment accordingly. Fixes: 779b1a1cb13a ("cpuidle: governors: menu: Avoid selecting states with too much latency") Closes: https://lore.kernel.org/linux-pm/004501dc43c9$ec8aa930$c59ffb90$@telus.net/ Reported-by: Doug Smythies Tested-by: Doug Smythies Cc: All applicable Signed-off-by: Rafael J. Wysocki Reviewed-by: Christian Loehle Link: https://patch.msgid.link/12786727.O9o76ZdvQC@rafael.j.wysocki Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

cpuidle: governors: menu: Rearrange main loop in menu_select()

2025-11-13T20:36:45+00:00

[ Upstream commit 17224c1d2574d29668c4879e1fbf36d6f68cd22b ] Reduce the indentation level in the main loop of menu_select() by rearranging some checks and assignments in it. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Christian Loehle Link: https://patch.msgid.link/2389215.ElGaqSPkdT@rafael.j.wysocki Stable-dep-of: db86f55bf81a ("cpuidle: governors: menu: Select polling state in some more cases") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

Revert "cpuidle: menu: Avoid discarding useful information"

2025-10-29T13:10:22+00:00

commit 10fad4012234a7dea621ae17c0c9486824f645a0 upstream. It is reported that commit 85975daeaa4d ("cpuidle: menu: Avoid discarding useful information") led to a performance regression on Intel Jasper Lake systems because it reduced the time spent by CPUs in idle state C7 which is correlated to the maximum frequency the CPUs can get to because of an average running power limit [1]. Before that commit, get_typical_interval() would have returned UINT_MAX whenever it had been unable to make a high-confidence prediction which had led to selecting the deepest available idle state too often and both power and performance had been inadequate as a result of that on some systems. However, this had not been a problem on systems with relatively aggressive average running power limits, like the Jasper Lake systems in question, because on those systems it was compensated by the ability to run CPUs faster. It was addressed by causing get_typical_interval() to return a number based on the recent idle duration information available to it even if it could not make a high-confidence prediction, but that clearly did not take the possible correlation between idle power and available CPU capacity into account. For this reason, revert most of the changes made by commit 85975daeaa4d, except for one cosmetic cleanup, and add a comment explaining the rationale for returning UINT_MAX from get_typical_interval() when it is unable to make a high-confidence prediction. Fixes: 85975daeaa4d ("cpuidle: menu: Avoid discarding useful information") Closes: https://lore.kernel.org/linux-pm/36iykr223vmcfsoysexug6s274nq2oimcu55ybn6ww4il3g3cv@cohflgdbpnq7/ [1] Reported-by: Sergey Senozhatsky Cc: All applicable Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/3663603.iIbC2pHGDl@rafael.j.wysocki Signed-off-by: Greg Kroah-Hartman

cpuidle: qcom-spm: fix device and OF node leaks at probe

2025-10-15T10:03:28+00:00

[ Upstream commit cdc06f912670c8c199d5fa9e78b64b7ed8e871d0 ] Make sure to drop the reference to the saw device taken by of_find_device_by_node() after retrieving its driver data during probe(). Also drop the reference to the CPU node sooner to avoid leaking it in case there is no saw node or device. Fixes: 60f3692b5f0b ("cpuidle: qcom_spm: Detach state machine from main SPM handling") Signed-off-by: Johan Hovold Reviewed-by: Konrad Dybcio Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

cpuidle: governors: menu: Avoid selecting states with too much latency

2025-08-18T17:04:25+00:00

Occasionally, the exit latency of the idle state selected by the menu governor may exceed the PM QoS CPU wakeup latency limit. Namely, if the scheduler tick has been stopped already and predicted_ns is greater than the tick period length, the governor may return an idle state whose exit latency exceeds latency_req because that decision is made before checking the current idle state's exit latency. For instance, say that there are 3 idle states, 0, 1, and 2. For idle states 0 and 1, the exit latency is equal to the target residency and the values are 0 and 5 us, respectively. State 2 is deeper and has the exit latency and target residency of 200 us and 2 ms (which is greater than the tick period length), respectively. Say that predicted_ns is equal to TICK_NSEC and the PM QoS latency limit is 20 us. After the first two iterations of the main loop in menu_select(), idx becomes 1 and in the third iteration of it the target residency of the current state (state 2) is greater than predicted_ns. State 2 is not a polling one and predicted_ns is not less than TICK_NSEC, so the check on whether or not the tick has been stopped is done. Say that the tick has been stopped already and there are no imminent timers (that is, delta_tick is greater than the target residency of state 2). In that case, idx becomes 2 and it is returned immediately, but the exit latency of state 2 exceeds the latency limit. Address this issue by modifying the code to compare the exit latency of the current idle state (idle state i) with the latency limit before comparing its target residency with predicted_ns, which allows one more exit_latency_ns check that becomes redundant to be dropped. However, after the above change, latency_req cannot take the predicted_ns value any more, which takes place after commit 38f83090f515 ("cpuidle: menu: Remove iowait influence"), because it may cause a polling state to be returned prematurely. In the context of the previous example say that predicted_ns is 3000 and the PM QoS latency limit is still 20 us. Additionally, say that idle state 0 is a polling one. Moving the exit_latency_ns check before the target_residency_ns one causes the loop to terminate in the second iteration, before the target_residency_ns check, so idle state 0 will be returned even though previously state 1 would be returned if there were no imminent timers. For this reason, remove the assignment of the predicted_ns value to latency_req from the code. Fixes: 5ef499cd571c ("cpuidle: menu: Handle stopped tick more aggressively") Cc: 4.17+ # 4.17+ Signed-off-by: Rafael J. Wysocki Reviewed-by: Christian Loehle Link: https://patch.msgid.link/5043159.31r3eYUQgx@rafael.j.wysocki

cpuidle: governors: menu: Avoid using invalid recent intervals data

2025-08-11T19:46:14+00:00

Marc has reported that commit 85975daeaa4d ("cpuidle: menu: Avoid discarding useful information") caused the number of wakeup interrupts to increase on an idle system [1], which was not expected to happen after merely allowing shallower idle states to be selected by the governor in some cases. However, on the system in question, all of the idle states deeper than WFI are rejected by the driver due to a firmware issue [2]. This causes the governor to only consider the recent interval duriation data corresponding to attempts to enter WFI that are successful and the recent invervals table is filled with values lower than the scheduler tick period. Consequently, the governor predicts an idle duration below the scheduler tick period length and avoids stopping the tick more often which leads to the observed symptom. Address it by modifying the governor to update the recent intervals table also when entering the previously selected idle state fails, so it knows that the short idle intervals might have been the minority had the selected idle states been actually entered every time. Fixes: 85975daeaa4d ("cpuidle: menu: Avoid discarding useful information") Link: https://lore.kernel.org/linux-pm/86o6sv6n94.wl-maz@kernel.org/ [1] Link: https://lore.kernel.org/linux-pm/7ffcb716-9a1b-48c2-aaa4-469d0df7c792@arm.com/ [2] Signed-off-by: Rafael J. Wysocki Tested-by: Christian Loehle Tested-by: Marc Zyngier Reviewed-by: Christian Loehle Link: https://patch.msgid.link/2793874.mvXUDI8C0e@rafael.j.wysocki

Merge tag 'pmdomain-v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/linux-pm

2025-07-29T18:42:31+00:00

Pull pmdomain updates from Ulf Hansson: "pmdomain core: - Leave powered-on genpds on until ->sync_state() or late_initcall_sync - Export a common ->sync_state() helper for genpd providers - Add generic ->sync_state() support - Add a bus/driver for genpd provider-devices - Introduce dev_pm_genpd_is_on() for consumers pmdomain providers: - cpuidle-psci: Drop redundant ->sync_state() support - cpuidle-riscv-sbi: Drop redundant ->sync_state() support - imx: Set ISI panic write for imx8m-blk-ctrl - qcom: Add support for Glymur and Milos RPMh power-domains - qcom: Use of_genpd_sync_state() for power-domains - rockchip: Add support for the RK3528 variant - samsung: Fix splash-screen handover by enforcing a ->sync_state() - sunxi: Add support for Allwinner A523's PCK600 power-controller - tegra: Opt-out from genpd's common ->sync_state() support for pmc - thead: Instantiate a GPU power sequencer via the auxiliary bus - renesas: Move init to postcore_initcalls - xilinx: Move ->sync_state() support to firmware driver - xilinx: Use of_genpd_sync_state() for power-domains pmdomain consumers: - remoteproc: imx_rproc: Fixup the detect/attach procedure for pre-booted cores" * tag 'pmdomain-v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/linux-pm: (44 commits) pmdomain: qcom: rpmhpd: Add Glymur RPMh Power Domains dt-bindings: power: rpmpd: Add Glymur power domains remoteproc: imx_rproc: detect and attach to pre-booted remote cores remoteproc: imx_rproc: skip clock enable when M-core is managed by the SCU pmdomain: core: introduce dev_pm_genpd_is_on() pmdomain: ti: Select PM_GENERIC_DOMAINS pmdomain: sunxi: sun20i-ppu: change to tristate and enable for ARCH_SUNXI pmdomain: sunxi: add driver for Allwinner A523's PCK-600 power controller pmdomain: sunxi: sun20i-ppu: add A523 support pmdomain: samsung: Fix splash-screen handover by enforcing a sync_state cpuidle: riscv-sbi: Drop redundant sync_state support cpuidle: psci: Drop redundant sync_state support pmdomain: core: Leave powered-on genpds on until sync_state pmdomain: core: Leave powered-on genpds on until late_initcall_sync pmdomain: core: Default to use of_genpd_sync_state() for genpd providers driver core: Add dev_set_drv_sync_state() pmdomain: core: Add common ->sync_state() support for genpd providers driver core: Export get_dev_from_fwnode() firmware: xilinx: Use of_genpd_sync_state() firmware: xilinx: Don't share zynqmp_pm_init_finalize() ...

Merge tag 'pm-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2025-07-29T03:13:36+00:00

Pull power management updates from Rafael Wysocki: "As is tradition, cpufreq is the part with the largest number of updates that include core fixes and cleanups as well as updates of several assorted drivers, but there are also quite a few updates related to system sleep, mostly focused on asynchronous suspend and resume of devices and on making the integration of system suspend and resume with runtime PM easier. Runtime PM is also updated to allow some code duplication in drivers to be eliminated going forward and to work more consistently overall in some cases. Apart from that, there are some driver core updates related to PM domains that should help to address ordering issues with devm_ cleanup routines relying on PM domains, some assorted devfreq updates including core fixes and cleanups, tooling updates, and documentation and MAINTAINERS updates. Specifics: - Fix two initialization ordering issues in the cpufreq core and a governor initialization error path in it, and clean it up (Lifeng Zheng) - Add Granite Rapids support in no-HWP mode to the intel_pstate cpufreq driver (Li RongQing) - Make intel_pstate always use HWP_DESIRED_PERF when operating in the passive mode (Rafael Wysocki) - Allow building the tegra124 cpufreq driver as a module (Aaron Kling) - Do minor cleanups for Rust cpufreq and cpumask APIs and fix MAINTAINERS entry for cpu.rs (Abhinav Ananthu, Ritvik Gupta, Lukas Bulwahn) - Clean up assorted cpufreq drivers (Arnd Bergmann, Dan Carpenter, Krzysztof Kozlowski, Sven Peter, Svyatoslav Ryhel, Lifeng Zheng) - Add the NEED_UPDATE_LIMITS flag to the CPPC cpufreq driver (Prashant Malani) - Fix minimum performance state label error in the amd-pstate driver documentation (Shouye Liu) - Add the CPUFREQ_GOV_STRICT_TARGET flag to the userspace cpufreq governor and explain HW coordination influence on it in the documentation (Shashank Balaji) - Fix opencoded for_each_cpu() in idle_state_valid() in the DT cpuidle driver (Yury Norov) - Remove info about non-existing QoS interfaces from the PM QoS documentation (Ulf Hansson) - Use c_* types via kernel prelude in Rust for OPP (Abhinav Ananthu) - Add HiSilicon uncore frequency scaling driver to devfreq (Jie Zhan) - Allow devfreq drivers to add custom sysfs ABIs (Jie Zhan) - Simplify the sun8i-a33-mbus devfreq driver by using more devm functions (Uwe Kleine-König) - Fix an index typo in trans_stat() in devfreq (Chanwoo Choi) - Check devfreq governor before using governor->name (Lifeng Zheng) - Remove a redundant devfreq_get_freq_range() call from devfreq_add_device() (Lifeng Zheng) - Limit max_freq with scaling_min_freq in devfreq (Lifeng Zheng) - Replace sscanf() with kstrtoul() in set_freq_store() (Lifeng Zheng) - Extend the asynchronous suspend and resume of devices to handle suppliers like parents and consumers like children (Rafael Wysocki) - Make pm_runtime_force_resume() work for drivers that set the DPM_FLAG_SMART_SUSPEND flag and allow PCI drivers and drivers that collaborate with the general ACPI PM domain to set it (Rafael Wysocki) - Add kernel parameter to disable asynchronous suspend/resume of devices (Tudor Ambarus) - Drop redundant might_sleep() calls from some functions in the device suspend/resume core code (Zhongqiu Han) - Fix the handling of monitors connected right before waking up the system from sleep (tuhaowen) - Clean up MAINTAINERS entries for suspend and hibernation (Rafael Wysocki) - Fix error code path in the KEXEC_JUMP flow and drop a redundant pm_restore_gfp_mask() call from it (Rafael Wysocki) - Rearrange suspend/resume error handling in the core device suspend and resume code (Rafael Wysocki) - Fix up white space that does not follow coding style in the hibernation core code (Darshan Rathod) - Document return values of suspend-related API functions in the runtime PM framework (Sakari Ailus) - Mark last busy stamp in multiple autosuspend-related functions in the runtime PM framework and update its documentation (Sakari Ailus) - Take active children into account in pm_runtime_get_if_in_use() for consistency (Rafael Wysocki) - Fix NULL pointer dereference in get_pd_power_uw() in the dtpm_cpu power capping driver (Sivan Zohar-Kotzer) - Add support for the Bartlett Lake platform to the Intel RAPL power capping driver (Qiao Wei) - Add PL4 support for Panther Lake to the intel_rapl_msr power capping driver (Zhang Rui) - Update contact information in the PM ABI docs and maintainer information in the power domains DT binding (Rafael Wysocki) - Update PM header inclusions to follow the IWYU (Include What You Use) principle (Andy Shevchenko) - Add flags to specify power on attach/detach for PM domains, make the driver core detach PM domains in device_unbind_cleanup(), and drop the dev_pm_domain_detach() call from the platform bus type (Claudiu Beznea) - Improve Python binding's Makefile for cpupower (John B. Wyatt IV) - Fix printing of CORE, CPU fields in cpupower-monitor (Gautham Shenoy)" * tag 'pm-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (75 commits) cpufreq: CPPC: Mark driver with NEED_UPDATE_LIMITS flag PM: docs: Use my kernel.org address in ABI docs and DT bindings PM: hibernate: Fix up white space that does not follow coding style PM: sleep: Rearrange suspend/resume error handling in the core Documentation: amd-pstate:fix minimum performance state label error PM: runtime: Take active children into account in pm_runtime_get_if_in_use() kexec_core: Drop redundant pm_restore_gfp_mask() call kexec_core: Fix error code path in the KEXEC_JUMP flow PM: sleep: Clean up MAINTAINERS entries for suspend and hibernation drivers: cpufreq: add Tegra114 support rust: cpumask: Replace `MaybeUninit` and `mem::zeroed` with `Opaque` APIs cpufreq: Exit governor when failed to start old governor cpufreq: Move the check of cpufreq_driver->get into cpufreq_verify_current_freq() cpufreq: Init policy->rwsem before it may be possibly used cpufreq: Initialize cpufreq-based frequency-invariance later cpufreq: Remove duplicate check in __cpufreq_offline() cpufreq: Contain scaling_cur_freq.attr in cpufreq_attrs cpufreq: intel_pstate: Add Granite Rapids support in no-HWP mode cpufreq: intel_pstate: Always use HWP_DESIRED_PERF in passive mode PM / devfreq: Add HiSilicon uncore frequency scaling driver ...

pmdomain: Merge branch fixes into next

2025-07-14T11:11:03+00:00

Merge the pmdomain fixes for v6.16-rc[n] into the next branch, to allow them to get tested together with the new changes that are targeted for v6.17. Signed-off-by: Ulf Hansson