<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/base/power/runtime.c, branch v6.15</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>Merge tag 'pm-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm</title>
<updated>2025-03-25T22:00:18+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-25T22:00:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7d20aa5c32ac8bd272b5470ddbd7ac6e0cb35714'/>
<id>7d20aa5c32ac8bd272b5470ddbd7ac6e0cb35714</id>
<content type='text'>
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
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'pm-sleep'</title>
<updated>2025-03-24T14:19:56+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2025-03-24T14:19:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5a98796468e655048a3b37bf94cbe9a36ce58e32'/>
<id>5a98796468e655048a3b37bf94cbe9a36ce58e32</id>
<content type='text'>
Merge updates related to system sleep for 6.15-rc1 including fixes,
cleanups and a rework of the "smart suspend" driver flag handling to
avoid issues that may occur when drivers using it depend on some other
drivers:

 - 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).

* pm-sleep:
  PM: sleep: Fix bit masking operation
  PM: sleep: Fix handling devices with direct_complete set on errors
  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
  PM: sleep: Rearrange dpm_async_fn() and async state clearing
  PM: sleep: Rename power.async_in_progress to power.work_in_progress
  PM: core: Tweak pm_runtime_block_if_disabled() return value
  PM: runtime: Convert pm_runtime_blocked() to static inline
  PM: sleep: Update power.smart_suspend under PM spinlock
  PM: sleep: Adjust check before setting power.must_resume
  PM: wakeup: Remove needless return in three void APIs
  PM: sleep: Suppress sleeping parent warning in special case
  PM: hibernate: Avoid deadlock in hibernate_compressor_param_set()
  PM: sleep: Avoid unnecessary checks in device_prepare_smart_suspend()
  PM: sleep: Use DPM_FLAG_SMART_SUSPEND conditionally
  PM: runtime: Introduce pm_runtime_blocked()
  PM: Block enabling of runtime PM during system suspend
  PM: hibernate: Replace deprecated kmap_atomic() with kmap_local_page()
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge updates related to system sleep for 6.15-rc1 including fixes,
cleanups and a rework of the "smart suspend" driver flag handling to
avoid issues that may occur when drivers using it depend on some other
drivers:

 - 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).

* pm-sleep:
  PM: sleep: Fix bit masking operation
  PM: sleep: Fix handling devices with direct_complete set on errors
  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
  PM: sleep: Rearrange dpm_async_fn() and async state clearing
  PM: sleep: Rename power.async_in_progress to power.work_in_progress
  PM: core: Tweak pm_runtime_block_if_disabled() return value
  PM: runtime: Convert pm_runtime_blocked() to static inline
  PM: sleep: Update power.smart_suspend under PM spinlock
  PM: sleep: Adjust check before setting power.must_resume
  PM: wakeup: Remove needless return in three void APIs
  PM: sleep: Suppress sleeping parent warning in special case
  PM: hibernate: Avoid deadlock in hibernate_compressor_param_set()
  PM: sleep: Avoid unnecessary checks in device_prepare_smart_suspend()
  PM: sleep: Use DPM_FLAG_SMART_SUSPEND conditionally
  PM: runtime: Introduce pm_runtime_blocked()
  PM: Block enabling of runtime PM during system suspend
  PM: hibernate: Replace deprecated kmap_atomic() with kmap_local_page()
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: Unify error handling during suspend and resume</title>
<updated>2025-03-03T13:46:19+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2025-02-25T17:06:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=72263869656d09a5f9727504bb1f3cb7b010f0e5'/>
<id>72263869656d09a5f9727504bb1f3cb7b010f0e5</id>
<content type='text'>
There is a confusing difference in error handling between rpm_suspend()
and rpm_resume() related to the special way in which -EAGAIN and -EBUSY
error values are treated by the former.  Also, converting -EACCES coming
from the callback to I/O error, which it quite likely is not, may
confuse runtime PM users.

To address the above, modify rpm_callback() to convert -EACCES coming
from the driver to -EAGAIN and to set power.runtime_error only if the
return value is not -EAGAIN or -EBUSY.

This will cause the error handling in rpm_resume() and rpm_suspend() to
work consistently, so drop the no longer needed -EAGAIN or -EBUSY
special case from the latter and make it retry autosuspend if
power.runtime_error is unset.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/12620037.O9o76ZdvQC@rjwysocki.net
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There is a confusing difference in error handling between rpm_suspend()
and rpm_resume() related to the special way in which -EAGAIN and -EBUSY
error values are treated by the former.  Also, converting -EACCES coming
from the callback to I/O error, which it quite likely is not, may
confuse runtime PM users.

To address the above, modify rpm_callback() to convert -EACCES coming
from the driver to -EAGAIN and to set power.runtime_error only if the
return value is not -EAGAIN or -EBUSY.

This will cause the error handling in rpm_resume() and rpm_suspend() to
work consistently, so drop the no longer needed -EAGAIN or -EBUSY
special case from the latter and make it retry autosuspend if
power.runtime_error is unset.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/12620037.O9o76ZdvQC@rjwysocki.net
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: core: Tweak pm_runtime_block_if_disabled() return value</title>
<updated>2025-03-03T13:35:07+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2025-02-27T10:49:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a84c2a885bc62a61e08fbcd9976a2a40400470c0'/>
<id>a84c2a885bc62a61e08fbcd9976a2a40400470c0</id>
<content type='text'>
Modify pm_runtime_block_if_disabled() to return true when runtime PM
is disabled for the device, regardless of the power.last_status value.

This effectively prevents "smart suspend" from being enabled for
devices with runtime PM disabled in device_prepare(), even transiently,
so update the related comment in that function accordingly.

If a device has runtime PM disabled in device_prepare(), it is not
actually known whether or not runtime PM will be enabled for that
device going forward, so it is more appropriate to postpone the
"smart suspend" optimization for the device in the given system
suspend-resume cycle than to enable it and get confused going
forward.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/13718674.uLZWGnKmhe@rjwysocki.net
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Modify pm_runtime_block_if_disabled() to return true when runtime PM
is disabled for the device, regardless of the power.last_status value.

This effectively prevents "smart suspend" from being enabled for
devices with runtime PM disabled in device_prepare(), even transiently,
so update the related comment in that function accordingly.

If a device has runtime PM disabled in device_prepare(), it is not
actually known whether or not runtime PM will be enabled for that
device going forward, so it is more appropriate to postpone the
"smart suspend" optimization for the device in the given system
suspend-resume cycle than to enable it and get confused going
forward.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/13718674.uLZWGnKmhe@rjwysocki.net
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: Convert pm_runtime_blocked() to static inline</title>
<updated>2025-03-03T13:35:07+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2025-02-27T10:47:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1476bb20eec33bd68b67c7bb7a5d62063af8148d'/>
<id>1476bb20eec33bd68b67c7bb7a5d62063af8148d</id>
<content type='text'>
The comment in pm_runtime_blocked() is acutally wrong: power.last_status
is not a bit field.  Its data type is an enum and so one can reasonably
assume that partial updates of it will not be observed.

Accordingly, pm_runtime_blocked() can be converted to a static inline
function and the related locking overhead can be eliminated, so long
as it is only used in system suspend/resume code paths because
power.last_status is not expected to be updated concurrently while
that code is running.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/1923449.tdWV9SEqCh@rjwysocki.net
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The comment in pm_runtime_blocked() is acutally wrong: power.last_status
is not a bit field.  Its data type is an enum and so one can reasonably
assume that partial updates of it will not be observed.

Accordingly, pm_runtime_blocked() can be converted to a static inline
function and the related locking overhead can be eliminated, so long
as it is only used in system suspend/resume code paths because
power.last_status is not expected to be updated concurrently while
that code is running.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/1923449.tdWV9SEqCh@rjwysocki.net
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: sleep: Adjust check before setting power.must_resume</title>
<updated>2025-03-03T13:31:47+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2025-02-27T10:53:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=eeb87d17aceab7803a5a5bcb6cf2817b745157cf'/>
<id>eeb87d17aceab7803a5a5bcb6cf2817b745157cf</id>
<content type='text'>
The check before setting power.must_resume in device_suspend_noirq()
does not take power.child_count into account, but it should do that, so
use pm_runtime_need_not_resume() in it for this purpose and adjust the
comment next to it accordingly.

Fixes: 107d47b2b95e ("PM: sleep: core: Simplify the SMART_SUSPEND flag handling")
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/3353728.44csPzL39Z@rjwysocki.net
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The check before setting power.must_resume in device_suspend_noirq()
does not take power.child_count into account, but it should do that, so
use pm_runtime_need_not_resume() in it for this purpose and adjust the
comment next to it accordingly.

Fixes: 107d47b2b95e ("PM: sleep: core: Simplify the SMART_SUSPEND flag handling")
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/3353728.44csPzL39Z@rjwysocki.net
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: Drop status check from pm_runtime_force_resume()</title>
<updated>2025-03-03T12:43:21+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2025-02-27T10:56:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d2677d57d4b8ec63da8f51357bcf855c4cf47c78'/>
<id>d2677d57d4b8ec63da8f51357bcf855c4cf47c78</id>
<content type='text'>
Since pm_runtime_force_resume() requires pm_runtime_force_suspend() to
be called before it on the same device, the runtime PM status of the
device is RPM_SUSPENDED when it is called unless the device's runtime
PM status is changed somewhere else in the meantime.

However, even if that happens, the power.needs_force_resume
check is still required to pass and that flag is only set by
pm_runtime_force_suspend() once and it is cleared at the end of
pm_runtime_force_resume(), so it cannot be taken into account
twice in a row.

According to the above, the pm_runtime_status_suspended(dev) check in
pm_runtime_force_resume() is redundant, so drop it.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/2309120.iZASKD2KPV@rjwysocki.net
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Since pm_runtime_force_resume() requires pm_runtime_force_suspend() to
be called before it on the same device, the runtime PM status of the
device is RPM_SUSPENDED when it is called unless the device's runtime
PM status is changed somewhere else in the meantime.

However, even if that happens, the power.needs_force_resume
check is still required to pass and that flag is only set by
pm_runtime_force_suspend() once and it is cleared at the end of
pm_runtime_force_resume(), so it cannot be taken into account
twice in a row.

According to the above, the pm_runtime_status_suspended(dev) check in
pm_runtime_force_resume() is redundant, so drop it.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/2309120.iZASKD2KPV@rjwysocki.net
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: sleep: Avoid unnecessary checks in device_prepare_smart_suspend()</title>
<updated>2025-03-03T12:29:00+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2025-02-18T20:20:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=520a552f19d55825108ab83da093084c9afb50e9'/>
<id>520a552f19d55825108ab83da093084c9afb50e9</id>
<content type='text'>
Add an optimization (on top of previous changes) to avoid calling
pm_runtime_blocked(), which involves acquiring the device's PM spinlock,
for devices with no PM callbacks and runtime PM "blocked".

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/2978873.e9J7NaK4W3@rjwysocki.net
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add an optimization (on top of previous changes) to avoid calling
pm_runtime_blocked(), which involves acquiring the device's PM spinlock,
for devices with no PM callbacks and runtime PM "blocked".

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/2978873.e9J7NaK4W3@rjwysocki.net
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: Introduce pm_runtime_blocked()</title>
<updated>2025-02-18T20:43:06+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2025-02-18T20:13:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=758cc55ce3d5d79e8f98adbd03ad2cd29133af33'/>
<id>758cc55ce3d5d79e8f98adbd03ad2cd29133af33</id>
<content type='text'>
Introduce a new helper function called pm_runtime_blocked()
for checking the power.last_status value indicating whether or not
enabling runtime PM for the given device has been blocked (which
happens in the "prepare" phase of system-wide suspend if runtime
PM is disabled for the given device at that point).

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/4632087.LvFx2qVVIh@rjwysocki.net
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Introduce a new helper function called pm_runtime_blocked()
for checking the power.last_status value indicating whether or not
enabling runtime PM for the given device has been blocked (which
happens in the "prepare" phase of system-wide suspend if runtime
PM is disabled for the given device at that point).

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/4632087.LvFx2qVVIh@rjwysocki.net
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: Block enabling of runtime PM during system suspend</title>
<updated>2025-02-18T20:43:06+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2025-02-18T20:11:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3e5eee147b7b0f5a93f56beffe34e81fdd00fa0d'/>
<id>3e5eee147b7b0f5a93f56beffe34e81fdd00fa0d</id>
<content type='text'>
If device_prepare() runs on a device that has never had runtime
PM enabled so far, it may reasonably assume that runtime PM will
not be enabled for that device during the system suspend-resume
cycle currently in progress, but this has never been guaranteed.

To verify this assumption, make device_prepare() arrange for
triggering a device warning accompanied by a call trace dump if
runtime PM is enabled for such a device after it has returned.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/6131109.lOV4Wx5bFT@rjwysocki.net
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If device_prepare() runs on a device that has never had runtime
PM enabled so far, it may reasonably assume that runtime PM will
not be enabled for that device during the system suspend-resume
cycle currently in progress, but this has never been guaranteed.

To verify this assumption, make device_prepare() arrange for
triggering a device warning accompanied by a call trace dump if
runtime PM is enabled for such a device after it has returned.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/6131109.lOV4Wx5bFT@rjwysocki.net
</pre>
</div>
</content>
</entry>
</feed>
