Drivers setting CPUFREQ_NEED_UPDATE_LIMITS expect target() to be
invoked even if the target frequency remains unchanged, so they can
update their internal policy limits state.
Currently the core invokes target() unconditionally whenever the
requested frequency matches policy->cur for such drivers, even if
policy->min and policy->max haven't changed since the previous update.
Track pending policy limit updates explicitly and skip redundant
target() invocations when neither the target frequency nor the
effective limits changed.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Reviewed-by: Zhongqiu Han <zhongqiu.han@oss.qualcomm.com>
Link: https://patch.msgid.link/d0107c364b709abca21acf88072220bc05478594.1779423281.git.viresh.kumar@linaro.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull amd-pstate new content for 7.1 (2026-04-02) from Mario Limonciello:
"Add support for new features:
* CPPC performance priority
* Dynamic EPP
* Raw EPP
* New unit tests for new features
Fixes for:
* PREEMPT_RT
* sysfs files being present when HW missing
* Broken/outdated documentation"
* tag 'amd-pstate-v7.1-2026-04-02' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/superm1/linux: (22 commits)
MAINTAINERS: amd-pstate: Step down as maintainer, add Prateek as reviewer
cpufreq: Pass the policy to cpufreq_driver->adjust_perf()
cpufreq/amd-pstate: Pass the policy to amd_pstate_update()
cpufreq/amd-pstate-ut: Add a unit test for raw EPP
cpufreq/amd-pstate: Add support for raw EPP writes
cpufreq/amd-pstate: Add support for platform profile class
cpufreq/amd-pstate: add kernel command line to override dynamic epp
cpufreq/amd-pstate: Add dynamic energy performance preference
Documentation: amd-pstate: fix dead links in the reference section
cpufreq/amd-pstate: Cache the max frequency in cpudata
Documentation/amd-pstate: Add documentation for amd_pstate_floor_{freq,count}
Documentation/amd-pstate: List amd_pstate_prefcore_ranking sysfs file
Documentation/amd-pstate: List amd_pstate_hw_prefcore sysfs file
amd-pstate-ut: Add a testcase to validate the visibility of driver attributes
amd-pstate-ut: Add module parameter to select testcases
amd-pstate: Introduce a tracepoint trace_amd_pstate_cppc_req2()
amd-pstate: Add sysfs support for floor_freq and floor_count
amd-pstate: Add support for CPPC_REQ2 and FLOOR_PERF
x86/cpufeatures: Add AMD CPPC Performance Priority feature.
amd-pstate: Make certain freq_attrs conditionally visible
...
cpufreq_cpu_get() can sleep on PREEMPT_RT in presence of concurrent
writer(s), however amd-pstate depends on fetching the cpudata via the
policy's driver data which necessitates grabbing the reference.
Since schedutil governor can call "cpufreq_driver->update_perf()"
during sched_tick/enqueue/dequeue with rq_lock held and IRQs disabled,
fetching the policy object using the cpufreq_cpu_get() helper in the
scheduler fast-path leads to "BUG: scheduling while atomic" on
PREEMPT_RT [1].
Pass the cached cpufreq policy object in sg_policy to the update_perf()
instead of just the CPU. The CPU can be inferred using "policy->cpu".
The lifetime of cpufreq_policy object outlasts that of the governor and
the cpufreq driver (allocated when the CPU is onlined and only reclaimed
when the CPU is offlined / the CPU device is removed) which makes it
safe to be referenced throughout the governor's lifetime.
Closes:https://lore.kernel.org/all/20250731092316.3191-1-spasswolf@web.de/ [1]
Fixes: 1d215f0319 ("cpufreq: amd-pstate: Add fast switch function for AMD P-State")
Reported-by: Bert Karwatzki <spasswolf@web.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>
Acked-by: Gary Guo <gary@garyguo.net> # Rust
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Reviewed-by: Zhongqiu Han <zhongqiu.han@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260316081849.19368-3-kprateek.nayak@amd.com
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
A recent change exposed a bug in the error path: if
freq_qos_add_request(boost_freq_req) fails, min_freq_req may remain a
valid pointer even though it was never successfully added. During policy
teardown, this leads to an unconditional call to
freq_qos_remove_request(), triggering a WARN.
The current design allocates all three freq_req objects together, making
the lifetime rules unclear and error handling fragile.
Simplify this by allocating the QoS freq_req objects at policy
allocation time. The policy itself is dynamically allocated, and two of
the three requests are always needed anyway. This ensures consistent
lifetime management and eliminates the inconsistent state in failure
paths.
Reported-by: Zhongqiu Han <zhongqiu.han@oss.qualcomm.com>
Fixes: 6e39ba4e5a ("cpufreq: Add boost_freq_req QoS request")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Tested-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Zhongqiu Han <zhongqiu.han@oss.qualcomm.com>
Link: https://patch.msgid.link/a293f29d841b86c51f34699c6e717e01858d8ada.1774933424.git.viresh.kumar@linaro.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The Power Management Quality of Service (PM QoS) allows to
aggregate constraints from multiple entities. It is currently
used to manage the min/max frequency of a given policy.
Frequency constraints can come for instance from:
- Thermal framework: acpi_thermal_cpufreq_init()
- Firmware: _PPC objects: acpi_processor_ppc_init()
- User: by setting policyX/scaling_[min|max]_freq
The minimum of the max frequency constraints is used to compute
the resulting maximum allowed frequency.
When enabling boost frequencies, the same frequency request object
(policy->max_freq_req) as to handle requests from users is used.
As a result, when setting:
- scaling_max_freq
- boost
The last sysfs file used overwrites the request from the other
sysfs file.
To avoid this, create a per-policy boost_freq_req to save the boost
constraints instead of overwriting the last scaling_max_freq
constraint.
policy_set_boost() calls the cpufreq set_boost callback.
Update the newly added boost_freq_req request from there:
- whenever boost is toggled
- to cover all possible paths
In the existing .set_boost() callbacks:
- Don't update policy->max as this is done through the qos notifier
cpufreq_notifier_max() which calls cpufreq_set_policy().
- Remove freq_qos_update_request() calls as the qos request is now
done in policy_set_boost() and updates the new boost_freq_req
$ ## Init state
scaling_max_freq:1000000
cpuinfo_max_freq:1000000
$ echo 700000 > scaling_max_freq
scaling_max_freq:700000
cpuinfo_max_freq:1000000
$ echo 1 > ../boost
scaling_max_freq:1200000
cpuinfo_max_freq:1200000
$ echo 800000 > scaling_max_freq
scaling_max_freq:800000
cpuinfo_max_freq:1200000
$ ## Final step:
$ ## Without the patches:
$ echo 0 > ../boost
scaling_max_freq:1000000
cpuinfo_max_freq:1000000
$ ## With the patches:
$ echo 0 > ../boost
scaling_max_freq:800000
cpuinfo_max_freq:1000000
Note:
cpufreq_frequency_table_cpuinfo() updates policy->min
and max from:
A.
cpufreq_boost_set_sw()
\-cpufreq_frequency_table_cpuinfo()
B.
cpufreq_policy_online()
\-cpufreq_table_validate_and_sort()
\-cpufreq_frequency_table_cpuinfo()
Keep these updates as some drivers expect policy->min and
max to be set through B.
Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/20260326204404.1401849-3-pierre.gondois@arm.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq_cpu_get_raw() gets cpufreq policy only if the CPU is in
policy->cpus mask, which means the CPU is already online. But in some
cases, the policy is needed before the CPU is added to cpus mask. Add a
function to get the policy in these cases.
Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Reviewed-by: Jie Zhan <zhanjie9@hisilicon.com>
Acked-by: Beata Michalska <beata.michalska@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Commit a755d0e2d4 ("cpufreq: Honour transition_latency over
transition_delay_us") caused platforms where cpuinfo.transition_latency
is CPUFREQ_ETERNAL to get a very large transition latency whereas
previously it had been capped at 10 ms (and later at 2 ms).
This led to a user-observable regression between 6.6 and 6.12 as
described by Shawn:
"The dbs sampling_rate was 10000 us on 6.6 and suddently becomes
6442450 us (4294967295 / 1000 * 1.5) on 6.12 for these platforms
because the default transition delay was dropped [...].
It slows down dbs governor's reacting to CPU loading change
dramatically. Also, as transition_delay_us is used by schedutil
governor as rate_limit_us, it shows a negative impact on device
idle power consumption, because the device gets slightly less time
in the lowest OPP."
Evidently, the expectation of the drivers using CPUFREQ_ETERNAL as
cpuinfo.transition_latency was that it would be capped by the core,
but they may as well return a default transition latency value instead
of CPUFREQ_ETERNAL and the core need not do anything with it.
Accordingly, introduce CPUFREQ_DEFAULT_TRANSITION_LATENCY_NS and make
all of the drivers in question use it instead of CPUFREQ_ETERNAL. Also
update the related Rust binding.
Fixes: a755d0e2d4 ("cpufreq: Honour transition_latency over transition_delay_us")
Closes: https://lore.kernel.org/linux-pm/20250922125929.453444-1-shawnguo2@yeah.net/
Reported-by: Shawn Guo <shawnguo@kernel.org>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Reviewed-by: Jie Zhan <zhanjie9@hisilicon.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 6.6+ <stable@vger.kernel.org> # 6.6+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/2264949.irdbgypaU6@rafael.j.wysocki
[ rjw: Fix typo in new symbol name, drop redundant type cast from Rust binding ]
Tested-by: Shawn Guo <shawnguo@kernel.org> # with cpufreq-dt driver
Reviewed-by: Qais Yousef <qyousef@layalina.io>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since commit e0b3165ba5 ("cpufreq: add 'freq_table' in struct
cpufreq_policy"), freq_table has been stored in struct cpufreq_policy
instead of being maintained separately.
However, several helpers in freq_table.c still take both policy and
freq_table as parameters, even though policy->freq_table can always be
used. This leads to redundant function arguments and increases the
chance of inconsistencies.
This patch removes the unnecessary freq_table argument from these
functions and updates their callers to only pass policy. This makes
the code simpler, more consistent, and avoids duplication.
Signed-off-by: Zihuan Zhang <zhangzihuan@kylinos.cn>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/20250902073323.48330-1-zhangzihuan@kylinos.cn
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Doing cpufreq-specific EAS checks that require accessing policy
internals directly from sched_is_eas_possible() is a bit unfortunate,
so introduce cpufreq_ready_for_eas() in cpufreq, move those checks
into that new function and make sched_is_eas_possible() call it.
While at it, address a possible race between the EAS governor check
and governor change by doing the former under the policy rwsem.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Christian Loehle <christian.loehle@arm.com>
Tested-by: Christian Loehle <christian.loehle@arm.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://patch.msgid.link/2317800.iZASKD2KPV@rjwysocki.net
Since cpufreq_update_limits() obtains a cpufreq policy pointer for the
given CPU and reference counts the corresponding policy object, it may
as well pass the policy pointer to the cpufreq driver's ->update_limits()
callback which allows that callback to avoid invoking cpufreq_cpu_get()
for the same CPU.
Accordingly, redefine ->update_limits() to take a policy pointer instead
of a CPU number and update both drivers implementing it, intel_pstate
and amd-pstate, as needed.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://patch.msgid.link/8560367.NyiUUSuA9g@rjwysocki.net
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
...
Merge ARM cpufreq updates for 6.15 from Viresh Kumar:
"- manage sysfs attributes and boost frequencies efficiently from cpufreq
core to reduce boilerplate code from drivers (Viresh Kumar).
- Minor cleanups to cpufreq drivers (Aaron Kling, Benjamin Schneider,
Dhananjay Ugwekar, Imran Shaik, and zuoqian).
- Migrate to using for_each_present_cpu (Jacky Bai).
- cpufreq-qcom-hw DT binding fixes (Krzysztof Kozlowski).
- Use str_enable_disable() helper (Lifeng Zheng)."
* tag 'cpufreq-arm-updates-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: (59 commits)
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
cpufreq: tegra186: Share policy per cluster
cpufreq: tegra194: Allow building for Tegra234
cpufreq: enable 1200Mhz clock speed for armada-37xx
cpufreq: Remove cpufreq_enable_boost_support()
cpufreq: staticize policy_has_boost_freq()
cpufreq: qcom: Set .set_boost directly
cpufreq: dt: Set .set_boost directly
cpufreq: scmi: Set .set_boost directly
cpufreq: powernv: Set .set_boost directly
cpufreq: loongson: Set .set_boost directly
cpufreq: apple: Set .set_boost directly
cpufreq: Restrict enabling boost on policies with no boost frequencies
cpufreq: cppc: Set policy->boost_supported
cpufreq: amd: Set policy->boost_supported
cpufreq: acpi: Set policy->boost_supported
...
