linux-toradex.git/include/linux/cpufreq.h, branch v5.4-rc8 Linux kernel for Apalis and Colibri modules cpufreq: Use per-policy frequency QoS 2019-10-21T00:05:21+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2019-10-16T10:47:06+00:00 3000ce3c52f8b8db093e4dc649cd172390f71137 Replace the CPU device PM QoS used for the management of min and max frequency constraints in cpufreq (and its users) with per-policy frequency QoS to avoid problems with cpufreq policies covering more then one CPU. Namely, a cpufreq driver is registered with the subsys interface which calls cpufreq_add_dev() for each CPU, starting from CPU0, so currently the PM QoS notifiers are added to the first CPU in the policy (i.e. CPU0 in the majority of cases). In turn, when the cpufreq driver is unregistered, the subsys interface doing that calls cpufreq_remove_dev() for each CPU, starting from CPU0, and the PM QoS notifiers are only removed when cpufreq_remove_dev() is called for the last CPU in the policy, say CPUx, which as a rule is not CPU0 if the policy covers more than one CPU. Then, the PM QoS notifiers cannot be removed, because CPUx does not have them, and they are still there in the device PM QoS notifiers list of CPU0, which prevents new PM QoS notifiers from being registered for CPU0 on the next attempt to register the cpufreq driver. The same issue occurs when the first CPU in the policy goes offline before unregistering the driver. After this change it does not matter which CPU is the policy CPU at the driver registration time and whether or not it is online all the time, because the frequency QoS is per policy and not per CPU. Fixes: 67d874c3b2c6 ("cpufreq: Register notifiers with the PM QoS framework") Reported-by: Dmitry Osipenko <digetx@gmail.com> Tested-by: Dmitry Osipenko <digetx@gmail.com> Reported-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Sudeep Holla <sudeep.holla@arm.com> Diagnosed-by: Viresh Kumar <viresh.kumar@linaro.org> Link: https://lore.kernel.org/linux-pm/5ad2624194baa2f53acc1f1e627eb7684c577a19.1562210705.git.viresh.kumar@linaro.org/T/#md2d89e95906b8c91c15f582146173dce2e86e99f Link: https://lore.kernel.org/linux-pm/20191017094612.6tbkwoq4harsjcqv@vireshk-i7/T/#m30d48cc23b9a80467fbaa16e30f90b3828a5a29b Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> 
Replace the CPU device PM QoS used for the management of min and max
frequency constraints in cpufreq (and its users) with per-policy
frequency QoS to avoid problems with cpufreq policies covering
more then one CPU.

Namely, a cpufreq driver is registered with the subsys interface
which calls cpufreq_add_dev() for each CPU, starting from CPU0, so
currently the PM QoS notifiers are added to the first CPU in the
policy (i.e. CPU0 in the majority of cases).

In turn, when the cpufreq driver is unregistered, the subsys interface
doing that calls cpufreq_remove_dev() for each CPU, starting from CPU0,
and the PM QoS notifiers are only removed when cpufreq_remove_dev() is
called for the last CPU in the policy, say CPUx, which as a rule is
not CPU0 if the policy covers more than one CPU.  Then, the PM QoS
notifiers cannot be removed, because CPUx does not have them, and
they are still there in the device PM QoS notifiers list of CPU0,
which prevents new PM QoS notifiers from being registered for CPU0
on the next attempt to register the cpufreq driver.

The same issue occurs when the first CPU in the policy goes offline
before unregistering the driver.

After this change it does not matter which CPU is the policy CPU at
the driver registration time and whether or not it is online all the
time, because the frequency QoS is per policy and not per CPU.

Fixes: 67d874c3b2c6 ("cpufreq: Register notifiers with the PM QoS framework")
Reported-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Reported-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Diagnosed-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lore.kernel.org/linux-pm/5ad2624194baa2f53acc1f1e627eb7684c577a19.1562210705.git.viresh.kumar@linaro.org/T/#md2d89e95906b8c91c15f582146173dce2e86e99f
Link: https://lore.kernel.org/linux-pm/20191017094612.6tbkwoq4harsjcqv@vireshk-i7/T/#m30d48cc23b9a80467fbaa16e30f90b3828a5a29b
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
cpufreq: Remove CPUFREQ_ADJUST and CPUFREQ_NOTIFY policy notifier events 2019-09-02T20:44:04+00:00 Viresh Kumar viresh.kumar@linaro.org 2019-07-23T06:14:09+00:00 df0eea4488081e0698b0b58ccd1e8c8823e22841 No driver makes reference to these events now, remove them and the code related to them. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
No driver makes reference to these events now, remove them and the code
related to them.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Add policy create/remove notifiers back 2019-08-10T12:05:48+00:00 Viresh Kumar viresh.kumar@linaro.org 2019-07-23T06:14:01+00:00 6a1490367c44f94614e39e8b98ff7114ff8a6449 This effectively reverts some changes made by commit f9f41e3ef99 ("cpufreq: Remove policy create/remove notifiers"). We have a new use case for policy create/remove notifiers (for allocating/freeing QoS requests per policy), so add them back. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
This effectively reverts some changes made by commit f9f41e3ef99
("cpufreq: Remove policy create/remove notifiers").

We have a new use case for policy create/remove notifiers (for
allocating/freeing QoS requests per policy), so add them back.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Merge branch 'pm-cpufreq' 2019-07-18T07:49:30+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2019-07-18T07:49:30+00:00 918e162e6a71e924a343b41f71789ad14e1e3229 * pm-cpufreq: cpufreq: Make cpufreq_generic_init() return void cpufreq: imx-cpufreq-dt: Add i.MX8MN support cpufreq: Add QoS requests for userspace constraints cpufreq: intel_pstate: Reuse refresh_frequency_limits() cpufreq: Register notifiers with the PM QoS framework PM / QoS: Add support for MIN/MAX frequency constraints PM / QOS: Pass request type to dev_pm_qos_read_value() PM / QOS: Rename __dev_pm_qos_read_value() and dev_pm_qos_raw_read_value() PM / QOS: Pass request type to dev_pm_qos_{add|remove}_notifier() 
* pm-cpufreq:
  cpufreq: Make cpufreq_generic_init() return void
  cpufreq: imx-cpufreq-dt: Add i.MX8MN support
  cpufreq: Add QoS requests for userspace constraints
  cpufreq: intel_pstate: Reuse refresh_frequency_limits()
  cpufreq: Register notifiers with the PM QoS framework
  PM / QoS: Add support for MIN/MAX frequency constraints
  PM / QOS: Pass request type to dev_pm_qos_read_value()
  PM / QOS: Rename __dev_pm_qos_read_value() and dev_pm_qos_raw_read_value()
  PM / QOS: Pass request type to dev_pm_qos_{add|remove}_notifier()
cpufreq: Make cpufreq_generic_init() return void 2019-07-16T08:20:11+00:00 Viresh Kumar viresh.kumar@linaro.org 2019-07-16T04:06:08+00:00 c4dcc8a162784c1f827c7f6d8409598f19708fe6 It always returns 0 (success) and its return type should really be void. Over that, many drivers have added error handling code based on its return value, which is not required at all. Change its return type to void and update all the callers. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
It always returns 0 (success) and its return type should really be void.

Over that, many drivers have added error handling code based on its
return value, which is not required at all.

Change its return type to void and update all the callers.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Add QoS requests for userspace constraints 2019-07-08T21:56:39+00:00 Viresh Kumar viresh.kumar@linaro.org 2019-07-05T10:51:24+00:00 18c49926c4bf4915e5194d1de3299c0537229f9f This implements QoS requests to manage userspace configuration of min and max frequency. Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: syzbot <syzbot+de771ae9390dffed7266@syzkaller.appspotmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
This implements QoS requests to manage userspace configuration of min
and max frequency.

Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: syzbot <syzbot+de771ae9390dffed7266@syzkaller.appspotmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: intel_pstate: Reuse refresh_frequency_limits() 2019-07-08T21:56:39+00:00 Viresh Kumar viresh.kumar@linaro.org 2019-07-04T07:36:22+00:00 c57b25bdf7cd374af106992356536bf5df7c255b The implementation of intel_pstate_update_max_freq() is quite similar to refresh_frequency_limits(), lets reuse it. Finding minimum of policy->user_policy.max and policy->cpuinfo.max_freq in intel_pstate_update_max_freq() is redundant as cpufreq_set_policy() will call the ->verify() callback of intel-pstate driver, which will do this comparison anyway and so dropping it from intel_pstate_update_max_freq() doesn't harm. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
The implementation of intel_pstate_update_max_freq() is quite similar to
refresh_frequency_limits(), lets reuse it.

Finding minimum of policy->user_policy.max and policy->cpuinfo.max_freq
in intel_pstate_update_max_freq() is redundant as cpufreq_set_policy()
will call the ->verify() callback of intel-pstate driver, which will do
this comparison anyway and so dropping it from
intel_pstate_update_max_freq() doesn't harm.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Register notifiers with the PM QoS framework 2019-07-08T21:56:13+00:00 Viresh Kumar viresh.kumar@linaro.org 2019-07-08T10:57:52+00:00 67d874c3b2c69d65274fa5ce44ba939788d5729d Register notifiers for min/max frequency constraints with the PM QoS framework. The constraints are also taken into consideration in cpufreq_set_policy(). This also relocates cpufreq_policy_put_kobj() as it is required to be called from cpufreq_policy_alloc() now. refresh_frequency_limits() is updated to avoid calling cpufreq_set_policy() for inactive policies and handle_update() is updated to have proper locking in place. No constraints are added until now though. Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Register notifiers for min/max frequency constraints with the PM QoS
framework. The constraints are also taken into consideration in
cpufreq_set_policy().

This also relocates cpufreq_policy_put_kobj() as it is required to be
called from cpufreq_policy_alloc() now.

refresh_frequency_limits() is updated to avoid calling
cpufreq_set_policy() for inactive policies and handle_update() is
updated to have proper locking in place.

No constraints are added until now though.

Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Merge branch 'pm-cpufreq' 2019-07-08T09:00:02+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2019-07-08T09:00:02+00:00 586a07dca8c51b966960d1f0d8be9c27d7e0a95c * pm-cpufreq: cpufreq: Avoid calling cpufreq_verify_current_freq() from handle_update() cpufreq: Consolidate cpufreq_update_current_freq() and __cpufreq_get() cpufreq: Don't skip frequency validation for has_target() drivers cpufreq: Use has_target() instead of !setpolicy cpufreq: Remove redundant !setpolicy check cpufreq: Move the IS_ENABLED(CPU_THERMAL) macro into a stub cpufreq: s5pv210: Don't flood kernel log after cpufreq change cpufreq: pcc-cpufreq: Fail initialization if driver cannot be registered cpufreq: add driver for Raspberry Pi cpufreq: Switch imx7d to imx-cpufreq-dt for speed grading cpufreq: imx-cpufreq-dt: Remove global platform match list cpufreq: brcmstb-avs-cpufreq: Fix types for voltage/frequency cpufreq: brcmstb-avs-cpufreq: Fix initial command check cpufreq: armada-37xx: Remove set but not used variable 'freq' cpufreq: imx-cpufreq-dt: Fix no OPPs available on unfused parts dt-bindings: imx-cpufreq-dt: Document opp-supported-hw usage cpufreq: Add imx-cpufreq-dt driver 
* pm-cpufreq:
  cpufreq: Avoid calling cpufreq_verify_current_freq() from handle_update()
  cpufreq: Consolidate cpufreq_update_current_freq() and __cpufreq_get()
  cpufreq: Don't skip frequency validation for has_target() drivers
  cpufreq: Use has_target() instead of !setpolicy
  cpufreq: Remove redundant !setpolicy check
  cpufreq: Move the IS_ENABLED(CPU_THERMAL) macro into a stub
  cpufreq: s5pv210: Don't flood kernel log after cpufreq change
  cpufreq: pcc-cpufreq: Fail initialization if driver cannot be registered
  cpufreq: add driver for Raspberry Pi
  cpufreq: Switch imx7d to imx-cpufreq-dt for speed grading
  cpufreq: imx-cpufreq-dt: Remove global platform match list
  cpufreq: brcmstb-avs-cpufreq: Fix types for voltage/frequency
  cpufreq: brcmstb-avs-cpufreq: Fix initial command check
  cpufreq: armada-37xx: Remove set but not used variable 'freq'
  cpufreq: imx-cpufreq-dt: Fix no OPPs available on unfused parts
  dt-bindings: imx-cpufreq-dt: Document opp-supported-hw usage
  cpufreq: Add imx-cpufreq-dt driver
cpufreq: Move the IS_ENABLED(CPU_THERMAL) macro into a stub 2019-06-26T08:59:57+00:00 Daniel Lezcano daniel.lezcano@linaro.org 2019-06-25T11:32:41+00:00 bcc61569997b2188ba89db43b5b991da01ea2d18 cpufreq_online() and cpufreq_offline() [un]register the driver as a cooling device. This is done if the driver is flagged as a cooling device in addition with an IS_ENABLED() check to compile out the branching code. Group this test in a stub function added in the cpufreq header instead of having the IS_ENABLED() in the code. Suggested-by: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
cpufreq_online() and cpufreq_offline() [un]register the driver as
a cooling device. This is done if the driver is flagged as a cooling
device in addition with an IS_ENABLED() check to compile out the branching
code.

Group this test in a stub function added in the cpufreq header instead
of having the IS_ENABLED() in the code.

Suggested-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>