linux-stable.git/drivers/cpuidle, branch linux-5.14.y

cpuidle: Fix kobject memory leaks in error paths

2021-11-17T10:04:03+00:00

[ Upstream commit e5f5a66c9aa9c331da5527c2e3fd9394e7091e01 ]

Commit c343bf1ba5ef ("cpuidle: Fix three reference count leaks")
fixes the cleanup of kobjects; however, it removes kfree() calls
altogether, leading to memory leaks.

Fix those and also defer the initialization of dev->kobj_dev until
after the error check, so that we do not end up with a dangling
pointer.

Fixes: c343bf1ba5ef ("cpuidle: Fix three reference count leaks")
Signed-off-by: Anel Orazgaliyeva 
Suggested-by: Aman Priyadarshi 
[ rjw: Subject edits ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

cpuidle: pseries: Mark pseries_idle_proble() as __init

2021-09-18T11:43:28+00:00

[ Upstream commit d04691d373e75c83424b85c0e68e4a3f9370c10d ]

After commit 7cbd631d4dec ("cpuidle: pseries: Fixup CEDE0 latency only
for POWER10 onwards"), pseries_idle_probe() is no longer inlined when
compiling with clang, which causes a modpost warning:

WARNING: modpost: vmlinux.o(.text+0xc86a54): Section mismatch in
reference from the function pseries_idle_probe() to the function
.init.text:fixup_cede0_latency()
The function pseries_idle_probe() references
the function __init fixup_cede0_latency().
This is often because pseries_idle_probe lacks a __init
annotation or the annotation of fixup_cede0_latency is wrong.

pseries_idle_probe() is a non-init function, which calls
fixup_cede0_latency(), which is an init function, explaining the
mismatch. pseries_idle_probe() is only called from
pseries_processor_idle_init(), which is an init function, so mark
pseries_idle_probe() as __init so there is no more warning.

Fixes: 054e44ba99ae ("cpuidle: pseries: Add function to parse extended CEDE records")
Signed-off-by: Nathan Chancellor 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210803211547.1093820-1-nathan@kernel.org
Signed-off-by: Sasha Levin

cpuidle: pseries: Fixup CEDE0 latency only for POWER10 onwards

2021-09-18T11:43:28+00:00

[ Upstream commit 50741b70b0cbbafbd9199f5180e66c0c53783a4a ]

Commit d947fb4c965c ("cpuidle: pseries: Fixup exit latency for
CEDE(0)") sets the exit latency of CEDE(0) based on the latency values
of the Extended CEDE states advertised by the platform

On POWER9 LPARs, the firmwares advertise a very low value of 2us for
CEDE1 exit latency on a Dedicated LPAR. The latency advertized by the
PHYP hypervisor corresponds to the latency required to wakeup from the
underlying hardware idle state. However the wakeup latency from the
LPAR perspective should include

1. The time taken to transition the CPU from the Hypervisor into the
   LPAR post wakeup from platform idle state

2. Time taken to send the IPI from the source CPU (waker) to the idle
   target CPU (wakee).

1. can be measured via timer idle test, where we queue a timer, say
for 1ms, and enter the CEDE state. When the timer fires, in the timer
handler we compute how much extra timer over the expected 1ms have we
consumed. On a a POWER9 LPAR the numbers are

CEDE latency measured using a timer (numbers in ns)
N       Min      Median   Avg       90%ile  99%ile    Max    Stddev
400     2601     5677     5668.74    5917    6413     9299   455.01

1. and 2. combined can be determined by an IPI latency test where we
send an IPI to an idle CPU and in the handler compute the time
difference between when the IPI was sent and when the handler ran. We
see the following numbers on POWER9 LPAR.

CEDE latency measured using an IPI (numbers in ns)
N       Min      Median   Avg       90%ile  99%ile    Max    Stddev
400     711      7564     7369.43   8559    9514      9698   1200.01

Suppose, we consider the 99th percentile latency value measured using
the IPI to be the wakeup latency, the value would be 9.5us This is in
the ballpark of the default value of 10us.

Hence, use the exit latency of CEDE(0) based on the latency values
advertized by platform only from POWER10 onwards. The values
advertized on POWER10 platforms is more realistic and informed by the
latency measurements. For earlier platforms stick to the default value
of 10us. The fix was suggested by Michael Ellerman.

Fixes: d947fb4c965c ("cpuidle: pseries: Fixup exit latency for CEDE(0)")
Reported-by: Enrico Joedecke 
Signed-off-by: Gautham R. Shenoy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/1626676399-15975-2-git-send-email-ego@linux.vnet.ibm.com
Signed-off-by: Sasha Levin

cpuidle: teo: Rename two local variables in teo_select()

2021-08-03T13:18:57+00:00

Rename two local variables in teo_select() so that their names better
reflect their purpose.

No functional impact.

Signed-off-by: Rafael J. Wysocki

cpuidle: teo: Fix alternative idle state lookup

2021-08-03T13:18:57+00:00

There are three mistakes in the loop in teo_select() that is looking
for an alternative candidate idle state.  First, it should walk all
of the idle states shallower than the current candidate one,
including all of the disabled ones, but it terminates after the first
enabled idle state.  Second, it should not terminate its last step
if idle state 0 is disabled (which is related to the first issue).
Finally, it may return the current alternative candidate idle state
prematurely if the time span criterion is not met by the idle state
under consideration at the moment.

To address the issues mentioned above, make the loop in question walk
all of the idle states shallower than the current candidate idle state
all the way down to idle state 0 and rearrange the checks in it.

Fixes: 77577558f25d ("cpuidle: teo: Rework most recent idle duration values treatment")
Reported-by: Doug Smythies 
Tested-by: Doug Smythies 
Signed-off-by: Rafael J. Wysocki

Merge tag 'cpuidle-v5.14-rc1' of https://git.linaro.org/people/daniel.lezcano/linux

2021-06-30T12:56:51+00:00

Pull ARM cpuidle updates for v5.14 from Daniel Lezcano:

"- Add support for Qcom MSM8226 (Bartosz Dudziak)"

* tag 'cpuidle-v5.14-rc1' of https://git.linaro.org/people/daniel.lezcano/linux:
  cpuidle: qcom: Add SPM register data for MSM8226
  dt-bindings: arm: msm: Add SAW2 for MSM8226

Merge tag 'pm-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2021-06-29T20:36:06+00:00

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()
  ...

cpuidle: teo: remove unneeded semicolon in teo_select()

2021-06-17T12:13:53+00:00

Fix following coccicheck warning:
drivers/cpuidle/governors/teo.c:315:10-11: Unneeded semicolon

Signed-off-by: Wan Jiabing 
Signed-off-by: Rafael J. Wysocki

cpuidle: qcom: Add SPM register data for MSM8226

2021-06-16T18:03:26+00:00

Add MSM8226 register data to SPM AVS Wrapper 2 (SAW2) power controller
driver.

Reviewed-by: Stephan Gerhold 
Signed-off-by: Bartosz Dudziak 
Signed-off-by: Daniel Lezcano 
Link: https://lore.kernel.org/r/20210612205335.9730-3-bartosz.dudziak@snejp.pl

cpuidle: teo: Use kerneldoc documentation in admin-guide

2021-06-11T16:36:45+00:00

There are two descriptions of the TEO (Timer Events Oriented) cpuidle
governor in the kernel source tree, one in the C file containing its
code and one in cpuidle.rst which is part of admin-guide.

Instead of trying to keep them both in sync and in order to reduce
text duplication, include the governor description from the C file
directly into cpuidle.rst.

Signed-off-by: Rafael J. Wysocki