linux-stable.git/drivers/cpuidle, branch v5.10.78

cpuidle: pseries: Mark pseries_idle_proble() as __init

2021-09-18T11:40:12+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

2021-09-18T11:40:12+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: Fix ARM_QCOM_SPM_CPUIDLE configuration

2021-05-14T07:50:16+00:00

[ Upstream commit 498ba2a8a2756694b6f3888857426dbc8a5e6b6c ]

When CONFIG_ARM_QCOM_SPM_CPUIDLE is y and CONFIG_MMU is not set,
compiling errors are encountered as follows:

drivers/cpuidle/cpuidle-qcom-spm.o: In function `spm_dev_probe':
cpuidle-qcom-spm.c:(.text+0x140): undefined reference to `cpu_resume_arm'
cpuidle-qcom-spm.c:(.text+0x148): undefined reference to `cpu_resume_arm'

Note that cpu_resume_arm is defined when MMU is set. So, add dependency
on MMU in ARM_QCOM_SPM_CPUIDLE configuration.

Fixes: a871be6b8eee ("cpuidle: Convert Qualcomm SPM driver to a generic CPUidle driver")
Reported-by: Hulk Robot 
Signed-off-by: He Ying 
Signed-off-by: Daniel Lezcano 
Link: https://lore.kernel.org/r/20210406123328.92904-1-heying24@huawei.com
Signed-off-by: Sasha Levin

cpuidle: tegra: Fix C7 idling state on Tegra114

2021-05-11T12:47:16+00:00

commit 32c8c34d8132b5fe8497c2538597445a0d65c29d upstream.

Trusted Foundation firmware doesn't implement the do_idle call and in
this case suspending should fall back to the common suspend path. In order
to fix this issue we will unconditionally set the NOFLUSH_L2 mode via
firmware call, which is a NO-OP on Tegra30/124, and then proceed to the
C7 idling, like it was done by the older Tegra114 cpuidle driver.

Fixes: 14e086baca50 ("cpuidle: tegra: Squash Tegra114 driver into the common driver")
Cc: stable@vger.kernel.org # 5.7+
Reported-by: Anton Bambura  # TF701 T114
Tested-by: Anton Bambura  # TF701 T114
Tested-by: Matt Merhar  # Ouya T30
Tested-by: Peter Geis  # Ouya T30
Signed-off-by: Dmitry Osipenko 
Reviewed-by: Daniel Lezcano 
Signed-off-by: Daniel Lezcano 
Link: https://lore.kernel.org/r/20210302095405.28453-1-digetx@gmail.com
Signed-off-by: Greg Kroah-Hartman

cpuidle: tegra: Annotate tegra_pm_set_cpu_in_lp2() with RCU_NONIDLE

2020-11-16T12:24:32+00:00

Annotate tegra_pm_set[clear]_cpu_in_lp2() with RCU_NONIDLE in order to
fix lockdep warning about suspicious RCU usage of a spinlock during late
idling phase.

 WARNING: suspicious RCU usage
 ...
 include/trace/events/lock.h:13 suspicious rcu_dereference_check() usage!
 ...
  (dump_stack) from (lock_acquire)
  (lock_acquire) from (_raw_spin_lock)
  (_raw_spin_lock) from (tegra_pm_set_cpu_in_lp2)
  (tegra_pm_set_cpu_in_lp2) from (tegra_cpuidle_enter)
  (tegra_cpuidle_enter) from (cpuidle_enter_state)
  (cpuidle_enter_state) from (cpuidle_enter_state_coupled)
  (cpuidle_enter_state_coupled) from (cpuidle_enter)
  (cpuidle_enter) from (do_idle)
 ...

Tested-by: Peter Geis 
Reported-by: Peter Geis 
Signed-off-by: Dmitry Osipenko 
Signed-off-by: Rafael J. Wysocki

Merge tag 'powerpc-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2020-10-16T19:21:15+00:00

Pull powerpc updates from Michael Ellerman:

 - A series from Nick adding ARCH_WANT_IRQS_OFF_ACTIVATE_MM & selecting
   it for powerpc, as well as a related fix for sparc.

 - Remove support for PowerPC 601.

 - Some fixes for watchpoints & addition of a new ptrace flag for
   detecting ISA v3.1 (Power10) watchpoint features.

 - A fix for kernels using 4K pages and the hash MMU on bare metal
   Power9 systems with > 16TB of RAM, or RAM on the 2nd node.

 - A basic idle driver for shallow stop states on Power10.

 - Tweaks to our sched domains code to better inform the scheduler about
   the hardware topology on Power9/10, where two SMT4 cores can be
   presented by firmware as an SMT8 core.

 - A series doing further reworks & cleanups of our EEH code.

 - Addition of a filter for RTAS (firmware) calls done via sys_rtas(),
   to prevent root from overwriting kernel memory.

 - Other smaller features, fixes & cleanups.

Thanks to: Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V,
Athira Rajeev, Biwen Li, Cameron Berkenpas, Cédric Le Goater, Christophe
Leroy, Christoph Hellwig, Colin Ian King, Daniel Axtens, David Dai, Finn
Thain, Frederic Barrat, Gautham R. Shenoy, Greg Kurz, Gustavo Romero,
Ira Weiny, Jason Yan, Joel Stanley, Jordan Niethe, Kajol Jain, Konrad
Rzeszutek Wilk, Laurent Dufour, Leonardo Bras, Liu Shixin, Luca
Ceresoli, Madhavan Srinivasan, Mahesh Salgaonkar, Nathan Lynch, Nicholas
Mc Guire, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Pedro
Miraglia Franco de Carvalho, Pratik Rajesh Sampat, Qian Cai, Qinglang
Miao, Ravi Bangoria, Russell Currey, Satheesh Rajendran, Scott Cheloha,
Segher Boessenkool, Srikar Dronamraju, Stan Johnson, Stephen Kitt,
Stephen Rothwell, Thiago Jung Bauermann, Tyrel Datwyler, Vaibhav Jain,
Vaidyanathan Srinivasan, Vasant Hegde, Wang Wensheng, Wolfram Sang, Yang
Yingliang, zhengbin.

* tag 'powerpc-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (228 commits)
  Revert "powerpc/pci: unmap legacy INTx interrupts when a PHB is removed"
  selftests/powerpc: Fix eeh-basic.sh exit codes
  cpufreq: powernv: Fix frame-size-overflow in powernv_cpufreq_reboot_notifier
  powerpc/time: Make get_tb() common to PPC32 and PPC64
  powerpc/time: Make get_tbl() common to PPC32 and PPC64
  powerpc/time: Remove get_tbu()
  powerpc/time: Avoid using get_tbl() and get_tbu() internally
  powerpc/time: Make mftb() common to PPC32 and PPC64
  powerpc/time: Rename mftbl() to mftb()
  powerpc/32s: Remove #ifdef CONFIG_PPC_BOOK3S_32 in head_book3s_32.S
  powerpc/32s: Rename head_32.S to head_book3s_32.S
  powerpc/32s: Setup the early hash table at all time.
  powerpc/time: Remove ifdef in get_dec() and set_dec()
  powerpc: Remove get_tb_or_rtc()
  powerpc: Remove __USE_RTC()
  powerpc: Tidy up a bit after removal of PowerPC 601.
  powerpc: Remove support for PowerPC 601
  powerpc: Remove PowerPC 601
  powerpc: Drop SYNC_601() ISYNC_601() and SYNC()
  powerpc: Remove CONFIG_PPC601_SYNC_FIX
  ...

Merge back cpuidle material for 5.10.

2020-09-28T14:31:25+00:00

cpuidle: record state entry rejection statistics

2020-09-23T12:10:31+00:00

CPUs may fail to enter the chosen idle state if there was a
pending interrupt, causing the cpuidle driver to return an error
value.

Record that and export it via sysfs along with the other idle state
statistics.

This could prove useful in understanding behavior of the governor
and the system during usecases that involve multiple CPUs.

Signed-off-by: Lina Iyer 
[ rjw: Changelog and documentation edits ]
Signed-off-by: Rafael J. Wysocki

cpuidle: Drop misleading comments about RCU usage

2020-09-22T17:32:03+00:00

The commit 1098582a0f6c ("sched,idle,rcu: Push rcu_idle deeper into the
idle path"), moved the calls rcu_idle_enter|exit() into the cpuidle core.

However, it forgot to remove a couple of comments in enter_s2idle_proper()
about why RCU_NONIDLE earlier was needed. So, let's drop them as they have
become a bit misleading.

Fixes: 1098582a0f6c ("sched,idle,rcu: Push rcu_idle deeper into the idle path")
Signed-off-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki

cpuidle: psci: Allow PM domain to be initialized even if no OSI mode

2020-09-22T15:50:32+00:00

If the PSCI OSI mode isn't supported or fails to be enabled, the PM domain
topology with the genpd providers isn't initialized. This is perfectly fine
from cpuidle-psci point of view.

However, since the PM domain topology in the DTS files is a description of
the HW, no matter of whether the PSCI OSI mode is supported or not, other
consumers besides the CPUs may rely on it.

Therefore, let's always allow the initialization of the PM domain topology
to succeed, independently of whether the PSCI OSI mode is supported.
Consequentially we need to track if we succeed to enable the OSI mode, as
to know when a domain idlestate can be selected.

Note that, CPU devices are still not being attached to the PM domain
topology, unless the PSCI OSI mode is supported.

Acked-by: Sudeep Holla 
Signed-off-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki