Dmitry writes:
"Input updates for v4.19-rc7
- we added a few scheduling points into various input interfaces to
ensure that large writes will not cause RCU stalls
- fixed configuring PS/2 keyboards as wakeup devices on newer
platforms
- added a new Xbox gamepad ID."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: uinput - add a schedule point in uinput_inject_events()
Input: evdev - add a schedule point in evdev_write()
Input: mousedev - add a schedule point in mousedev_write()
Input: i8042 - enable keyboard wakeups by default when s2idle is used
Input: xpad - add support for Xbox1 PDP Camo series gamepad
Previously, on typical consumer laptops, pressing a key on the keyboard
when the system is in suspend would cause it to wake up (default or
unconditional behaviour). This happens because the EC generates a SCI
interrupt in this scenario.
That is no longer true on modern laptops based on Intel WhiskeyLake,
including Acer Swift SF314-55G, Asus UX333FA, Asus UX433FN and Asus
UX533FD. We confirmed with Asus EC engineers that the "Modern Standby"
design has been modified so that the EC no longer generates a SCI
in this case; the keyboard controller itself should be used for wakeup.
In order to retain the standard behaviour of being able to use the
keyboard to wake up the system, enable serio wakeups by default on
platforms that are using s2idle.
Link: https://lkml.kernel.org/r/CAB4CAwfQ0mPMqCLp95TVjw4J0r5zKPWkSvvkK4cpZUGE--w8bQ@mail.gmail.com
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
- Add a new framework for CPU idle time injection (Daniel Lezcano).
- Add AVS support to the armada-37xx cpufreq driver (Gregory CLEMENT).
- Add support for current CPU frequency reporting to the ACPI CPPC
cpufreq driver (George Cherian).
- Rework the cooling device registration in the imx6q/thermal
driver (Bastian Stender).
- Make the pcc-cpufreq driver refuse to work with dynamic
scaling governors on systems with many CPUs to avoid
scalability issues with it (Rafael Wysocki).
- Fix the intel_pstate driver to report different maximum CPU
frequencies on systems where they really are different and to
ignore the turbo active ratio if hardware-managend P-states (HWP)
are in use; make it use the match_string() helper (Xie Yisheng,
Srinivas Pandruvada).
- Fix a minor deferred probe issue in the qcom-kryo cpufreq
driver (Niklas Cassel).
- Add a tracepoint for the tracking of frequency limits changes
(from Andriod) to the cpufreq core (Ruchi Kandoi).
- Fix a circular lock dependency between CPU hotplug and sysfs
locking in the cpufreq core reported by lockdep (Waiman Long).
- Avoid excessive error reports on driver registration failures
in the ARM cpuidle driver (Sudeep Holla).
- Add a new device links flag to the driver core to make links go
away automatically on supplier driver removal (Vivek Gautam).
- Eliminate potential race condition between system-wide power
management transitions and system shutdown (Pingfan Liu).
- Add a quirk to save NVS memory on system suspend for the ASUS
1025C laptop (Willy Tarreau).
- Make more systems use suspend-to-idle (instead of ACPI S3) by
default (Tristian Celestin).
- Get rid of stack VLA usage in the low-level hibernation code on
64-bit x86 (Kees Cook).
- Fix error handling in the hibernation core and mark an expected
fall-through switch in it (Chengguang Xu, Gustavo Silva).
- Extend the generic power domains (genpd) framework to support
attaching a device to a power domain by name (Ulf Hansson).
- Fix device reference counting and user limits initialization in
the devfreq core (Arvind Yadav, Matthias Kaehlcke).
- Fix a few issues in the rk3399_dmc devfreq driver and improve its
documentation (Enric Balletbo i Serra, Lin Huang, Nick Milner).
- Drop a redundant error message from the exynos-ppmu devfreq driver
(Markus Elfring).
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Merge tag 'pm-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These add a new framework for CPU idle time injection, to be used by
all of the idle injection code in the kernel in the future, fix some
issues and add a number of relatively small extensions in multiple
places.
Specifics:
- Add a new framework for CPU idle time injection (Daniel Lezcano).
- Add AVS support to the armada-37xx cpufreq driver (Gregory
CLEMENT).
- Add support for current CPU frequency reporting to the ACPI CPPC
cpufreq driver (George Cherian).
- Rework the cooling device registration in the imx6q/thermal driver
(Bastian Stender).
- Make the pcc-cpufreq driver refuse to work with dynamic scaling
governors on systems with many CPUs to avoid scalability issues
with it (Rafael Wysocki).
- Fix the intel_pstate driver to report different maximum CPU
frequencies on systems where they really are different and to
ignore the turbo active ratio if hardware-managend P-states (HWP)
are in use; make it use the match_string() helper (Xie Yisheng,
Srinivas Pandruvada).
- Fix a minor deferred probe issue in the qcom-kryo cpufreq driver
(Niklas Cassel).
- Add a tracepoint for the tracking of frequency limits changes (from
Andriod) to the cpufreq core (Ruchi Kandoi).
- Fix a circular lock dependency between CPU hotplug and sysfs
locking in the cpufreq core reported by lockdep (Waiman Long).
- Avoid excessive error reports on driver registration failures in
the ARM cpuidle driver (Sudeep Holla).
- Add a new device links flag to the driver core to make links go
away automatically on supplier driver removal (Vivek Gautam).
- Eliminate potential race condition between system-wide power
management transitions and system shutdown (Pingfan Liu).
- Add a quirk to save NVS memory on system suspend for the ASUS 1025C
laptop (Willy Tarreau).
- Make more systems use suspend-to-idle (instead of ACPI S3) by
default (Tristian Celestin).
- Get rid of stack VLA usage in the low-level hibernation code on
64-bit x86 (Kees Cook).
- Fix error handling in the hibernation core and mark an expected
fall-through switch in it (Chengguang Xu, Gustavo Silva).
- Extend the generic power domains (genpd) framework to support
attaching a device to a power domain by name (Ulf Hansson).
- Fix device reference counting and user limits initialization in the
devfreq core (Arvind Yadav, Matthias Kaehlcke).
- Fix a few issues in the rk3399_dmc devfreq driver and improve its
documentation (Enric Balletbo i Serra, Lin Huang, Nick Milner).
- Drop a redundant error message from the exynos-ppmu devfreq driver
(Markus Elfring)"
* tag 'pm-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (35 commits)
PM / reboot: Eliminate race between reboot and suspend
PM / hibernate: Mark expected switch fall-through
cpufreq: intel_pstate: Ignore turbo active ratio in HWP
cpufreq: Fix a circular lock dependency problem
cpu/hotplug: Add a cpus_read_trylock() function
x86/power/hibernate_64: Remove VLA usage
cpufreq: trace frequency limits change
cpufreq: intel_pstate: Show different max frequency with turbo 3 and HWP
cpufreq: pcc-cpufreq: Disable dynamic scaling on many-CPU systems
cpufreq: qcom-kryo: Silently error out on EPROBE_DEFER
cpufreq / CPPC: Add cpuinfo_cur_freq support for CPPC
cpufreq: armada-37xx: Add AVS support
dt-bindings: marvell: Add documentation for the Armada 3700 AVS binding
PM / devfreq: rk3399_dmc: Fix duplicated opp table on reload.
PM / devfreq: Init user limits from OPP limits, not viceversa
PM / devfreq: rk3399_dmc: fix spelling mistakes.
PM / devfreq: rk3399_dmc: do not print error when get supply and clk defer.
dt-bindings: devfreq: rk3399_dmc: move interrupts to be optional.
PM / devfreq: rk3399_dmc: remove wait for dcf irq event.
dt-bindings: clock: add rk3399 DDR3 standard speed bins.
...
At present, "systemctl suspend" and "shutdown" can run in parrallel. A
system can suspend after devices_shutdown(), and resume. Then the shutdown
task goes on to power off. This causes many devices are not really shut
off. Hence replacing reboot_mutex with system_transition_mutex (renamed
from pm_mutex) to achieve the exclusion. The renaming of pm_mutex as
system_transition_mutex can be better to reflect the purpose of the mutex.
Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The `s2idle_lock' is acquired during suspend while interrupts are
disabled even on RT. The lock is acquired for short sections only.
Make it a RAW lock which avoids "sleeping while atomic" warnings on RT.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
s2idle_wait_head is used during s2idle with interrupts disabled even on
RT. There is no "custom" wake up function so swait could be used instead
which is also lower weight compared to the wait_queue.
Make s2idle_wait_head a swait_queue_head.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
timekeeping suspend/resume calls read_persistent_clock() which takes
rtc_lock. That results in might sleep warnings because at that point
we run with interrupts disabled.
We cannot convert rtc_lock to a raw spinlock as that would trigger
other might sleep warnings.
As a workaround we disable the might sleep warnings by setting
system_state to SYSTEM_SUSPEND before calling sysdev_suspend() and
restoring it to SYSTEM_RUNNING afer sysdev_resume(). There is no lock
contention because hibernate / suspend to RAM is single-CPU at this
point.
In s2idle's case the system_state is set to SYSTEM_SUSPEND before
timekeeping_suspend() which is invoked by the last CPU. In the resume
case it set back to SYSTEM_RUNNING after timekeeping_resume() which is
invoked by the first CPU in the resume case. The other CPUs will block
on tick_freeze_lock.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bigeasy: cover s2idle in tick_freeze() / tick_unfreeze()]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Using this helper allows us to avoid the in-kernel calls to the
sys_sync() syscall. The ksys_ prefix denotes that this function
is meant as a drop-in replacement for the syscall. In particular, it
uses the same calling convention as sys_sync().
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Problem: This flag does not get cleared currently in the suspend or
resume path in the following cases:
* In case some driver's suspend routine returns an error.
* Successful s2idle case
* etc?
Why is this a problem: What happens is that the next suspend attempt
could fail even though the user did not enable the flag by writing to
/sys/power/wakeup_count. This is 1 use case how the issue can be seen
(but similar use case with driver suspend failure can be thought of):
1. Read /sys/power/wakeup_count
2. echo count > /sys/power/wakeup_count
3. echo freeze > /sys/power/wakeup_count
4. Let the system suspend, and wakeup the system using some wake source
that calls pm_wakeup_event() e.g. power button or something.
5. Note that the combined wakeup count would be incremented due
to the pm_wakeup_event() in the resume path.
6. After resuming the events_check_enabled flag is still set.
At this point if the user attempts to freeze again (without writing to
/sys/power/wakeup_count), the suspend would fail even though there has
been no wake event since the past resume.
Address that by clearing the flag just before a resume is completed,
so that it is always cleared for the corner cases mentioned above.
Signed-off-by: Rajat Jain <rajatja@google.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The role of the ->wake() platform callback for suspend-to-idle is to
deal with possible spurious wakeups, among other things. The ACPI
implementation of it, acpi_s2idle_wake(), additionally checks the
conditions for entering the Low Power S0 Idle state by the platform
and reports the ones that have not been met.
However, the ->wake() platform callback is invoked after calling
dpm_noirq_resume_devices(), which means that the power states of some
devices may have changed since s2idle_enter() returned, so some unmet
Low Power S0 Idle conditions may be reported incorrectly as a result
of that.
To avoid these false positives, reorder the invocations of the
dpm_noirq_resume_devices() routine and the ->wake() platform callback
in s2idle_loop().
Fixes: 726fb6b4f2 (ACPI / PM: Check low power idle constraints for debug only)
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rename struct platform_freeze_ops to platform_s2idle_ops to make it
clear that the callbacks in it are used during suspend-to-idle
suspend/resume transitions and rename the related functions,
variables and so on accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rename the freeze_state enum representing the suspend-to-idle state
machine states to s2idle_states and rename the related variables and
functions accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
To make it clear that the symbol in question refers to
suspend-to-idle, rename it from PM_SUSPEND_FREEZE to
PM_SUSPEND_TO_IDLE.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Modify the ACPI system sleep support setup code to select
suspend-to-idle as the default system sleep state if
(1) the ACPI_FADT_LOW_POWER_S0 flag is set in the FADT and
(2) the Low Power Idle S0 _DSM interface has been discovered and
(3) the default sleep state was not selected from the kernel command
line.
The main motivation for this change is that systems where the (1) and
(2) conditions are met typically ship with OSes that don't exercise
the S3 path in the platform firmware which remains untested and turns
out to be non-functional at least in some cases.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mario Limonciello <mario.limonciello@dell.com>
Define a common prefix ("PM:") for messages printed by the
code in kernel/power/suspend.c.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Some messages in suspend.c currently print state names from
pm_states[], but that may be confusing if the mem_sleep sysfs
attribute is changed to anything different from "mem", because
in those cases the messages will say either "freeze" or "standby"
after writing "mem" to /sys/power/state.
To avoid the confusion, use mem_sleep_labels[] strings in those
messages instead.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Restore the pm_wakeup_pending() check in __device_suspend_noirq()
removed by commit eed4d47efe (ACPI / sleep: Ignore spurious SCI
wakeups from suspend-to-idle) as that allows the function to return
earlier if there's a wakeup event pending already (so that it may
spend less time on carrying out operations that will be reversed
shortly anyway) and rework the main suspend-to-idle loop to take
that optimization into account.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
As a preparation for subsequent changes, rearrange the core
suspend-to-idle code by moving the initial invocation of
dpm_suspend_noirq() into s2idle_loop().
This also causes debug messages from that code to appear in
a less confusing order.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Regardless of whether or not debug messages from the core system
suspend/hibernation code are enabled, it is useful to know when
system-wide transitions start and finish (or fail), so print "info"
messages at these points.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mark Salyzyn <salyzyn@android.com>
Debug messages from the system suspend/hibernation infrastructure can
fill up the entire kernel log buffer in some cases and anyway they
are only useful for debugging. They depend on CONFIG_PM_DEBUG, but
that is set as a rule as some generally useful diagnostic facilities
depend on it too.
For this reason, avoid printing those messages by default, but make
it possible to turn them on as needed with the help of a new sysfs
attribute under /sys/power/.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Have the core suspend/resume framework store the system-wide suspend
state (suspend_state_t) we are about to enter, and expose it to drivers
via pm_suspend_target_state in order to retrieve that. The state is
assigned in suspend_devices_and_enter().
This is useful for platform specific drivers that may need to take a
slightly different suspend/resume path based on the system's
suspend/resume state being entered.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ACPI SCI (System Control Interrupt) is set up as a wakeup IRQ
during suspend-to-idle transitions and, consequently, any events
signaled through it wake up the system from that state. However,
on some systems some of the events signaled via the ACPI SCI while
suspended to idle should not cause the system to wake up. In fact,
quite often they should just be discarded.
Arguably, systems should not resume entirely on such events, but in
order to decide which events really should cause the system to resume
and which are spurious, it is necessary to resume up to the point
when ACPI SCIs are actually handled and processed, which is after
executing dpm_resume_noirq() in the system resume path.
For this reasons, add a loop around freeze_enter() in which the
platforms can process events signaled via multiplexed IRQ lines
like the ACPI SCI and add suspend-to-idle hooks that can be
used for this purpose to struct platform_freeze_ops.
In the ACPI case, the ->wake hook is used for checking if the SCI
has triggered while suspended and deferring the interrupt-induced
system wakeup until the events signaled through it are actually
processed sufficiently to decide whether or not the system should
resume. In turn, the ->sync hook allows all of the relevant event
queues to be flushed so as to prevent events from being missed due
to race conditions.
In addition to that, some ACPI code processing wakeup events needs
to be modified to use the "hard" version of wakeup triggers, so that
it will cause a system resume to happen on device-induced wakeup
events even if the "soft" mechanism to prevent the system from
suspending is not enabled. However, to preserve the existing
behavior with respect to suspend-to-RAM, this only is done in
the suspend-to-idle case and only if an SCI has occurred while
suspended.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Revert commit eed4d47efe (ACPI / sleep: Ignore spurious SCI wakeups
from suspend-to-idle) as it turned out to be premature and triggered
a number of different issues on various systems.
That includes, but is not limited to, premature suspend-to-RAM aborts
on Dell XPS 13 (9343) reported by Dominik.
The issue the commit in question attempted to address is real and
will need to be taken care of going forward, but evidently more work
is needed for this purpose.
Reported-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ACPI SCI (System Control Interrupt) is set up as a wakeup IRQ
during suspend-to-idle transitions and, consequently, any events
signaled through it wake up the system from that state. However,
on some systems some of the events signaled via the ACPI SCI while
suspended to idle should not cause the system to wake up. In fact,
quite often they should just be discarded.
Arguably, systems should not resume entirely on such events, but in
order to decide which events really should cause the system to resume
and which are spurious, it is necessary to resume up to the point
when ACPI SCIs are actually handled and processed, which is after
executing dpm_resume_noirq() in the system resume path.
For this reasons, add a loop around freeze_enter() in which the
platforms can process events signaled via multiplexed IRQ lines
like the ACPI SCI and add suspend-to-idle hooks that can be
used for this purpose to struct platform_freeze_ops.
In the ACPI case, the ->wake hook is used for checking if the SCI
has triggered while suspended and deferring the interrupt-induced
system wakeup until the events signaled through it are actually
processed sufficiently to decide whether or not the system should
resume. In turn, the ->sync hook allows all of the relevant event
queues to be flushed so as to prevent events from being missed due
to race conditions.
In addition to that, some ACPI code processing wakeup events needs
to be modified to use the "hard" version of wakeup triggers, so that
it will cause a system resume to happen on device-induced wakeup
events even if the "soft" mechanism to prevent the system from
suspending is not enabled (that also helps to catch device-induced
wakeup events occurring during suspend transitions in progress).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Revert commit 08b98d3291 (PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0
flag) as it caused system suspend (in the default configuration) to fail
on Dell XPS13 (9360) with the Kaby Lake processor.
Fixes: 08b98d3291 (PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0 flag)
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Modify the ACPI system sleep support setup code to select
suspend-to-idle as the default system sleep state if the
ACPI_FADT_LOW_POWER_S0 flag is set in the FADT and the
default sleep state was not selected from the kernel command
line.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mario Limonciello <mario.limonciello@dell.com>
There are systems in which the platform doesn't support any special
sleep states, so suspend-to-idle (PM_SUSPEND_FREEZE) is the only
available system sleep state. However, some user space frameworks
only use the "mem" and (sometimes) "standby" sleep state labels, so
the users of those systems need to modify user space in order to be
able to use system suspend at all and that may be a pain in practice.
Commit 0399d4db3e (PM / sleep: Introduce command line argument for
sleep state enumeration) attempted to address this problem by adding
a command line argument to change the meaning of the "mem" string in
/sys/power/state to make it trigger suspend-to-idle (instead of
suspend-to-RAM).
However, there also are systems in which the platform does support
special sleep states, but suspend-to-idle is the preferred one anyway
(it even may save more energy than the platform-provided sleep states
in some cases) and the above commit doesn't help in those cases.
For this reason, rework the system sleep state selection interface
again (but preserve backwards compatibiliby). Namely, add a new
sysfs file, /sys/power/mem_sleep, that will control the system
suspend mode triggered by writing "mem" to /sys/power/state (in
analogy with what /sys/power/disk does for hibernation). Make it
select suspend-to-RAM ("deep" sleep) by default (if supported) and
fall back to suspend-to-idle ("s2idle") otherwise and add a new
command line argument, mem_sleep_default, allowing that default to
be overridden if need be.
At the same time, drop the relative_sleep_states command line
argument that doesn't make sense any more.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mario Limonciello <mario.limonciello@dell.com>
Commit 4bcc595ccd (printk: reinstate KERN_CONT for printing
continuation lines) exposed a missing KERN_CONT from one of the
messages shown on entering suspend. With v4.9-rc1, the 'done.' shown
after syncing the filesystems no longer appears as a continuation but
a new message with its own timestamp.
[ 9.259566] PM: Syncing filesystems ... [ 9.264119] done.
Fix this by adding the KERN_CONT log level for the 'done.' part of the
message seen after syncing filesystems. While we are at it, convert
these suspend printks to pr_info and pr_cont, respectively.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Suspend-to-idle (aka the "freeze" sleep state) is a system sleep state
in which all of the processors enter deepest possible idle state and
wait for interrupts right after suspending all the devices.
There is no hard requirement for a platform to support and register
platform specific suspend_ops to enter suspend-to-idle/freeze state.
Only deeper system sleep states like PM_SUSPEND_STANDBY and
PM_SUSPEND_MEM rely on such low level support/implementation.
suspend-to-idle can be entered as along as all the devices can be
suspended. This patch enables the support for suspend-to-idle even on
systems that don't have any low level support for deeper system sleep
states and/or don't register any platform specific suspend_ops.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Andy Gross <andy.gross@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This makes pm notifier PREPARE/POST symmetrical: if PREPARE
fails, we will only undo what ever happened on PREPARE.
It fixes the unbalanced CPU hotplug enable in CPU PM notifier.
Signed-off-by: Lianwei Wang <lianwei.wang@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Use the more common logging method with the eventual goal of removing
pr_warning altogether.
Miscellanea:
- Realign arguments
- Coalesce formats
- Add missing space between a few coalesced formats
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [kernel/power/suspend.c]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
replacing printk(s) with appropriate pr_info and pr_err
in order to fix checkpatch.pl warnings
Signed-off-by: Saurabh Sengar <saurabh.truth@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There are quite a few cases in which device drivers, bus types or
even the PM core itself may benefit from knowing whether or not
the platform firmware will be involved in the upcoming system power
transition (during system suspend) or whether or not it was involved
in it (during system resume).
For this reason, introduce global system suspend flags that can be
used by the platform code to expose that information for the benefit
of the other parts of the kernel and make the ACPI core set them
as appropriate.
Users of the new flags will be added later.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The Linux kernel suspend path has traditionally invoked sys_sync()
before freezing user threads.
But sys_sync() can be expensive, and some user-space OS's do not want
the kernel to pay the cost of sys_sync() on every suspend -- preferring
invoke sync() from user-space if/when they want it.
So make sys_sync on suspend build-time optional.
The default is unchanged.
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If a wakeup source is found to be pending in the last stage of
suspend after syscore suspend, then the machine won't suspend, but
suspend_enter() will return 0. That is confusing, as wakeup detection
elsewhere causes -EBUSY to be returned from suspend_enter().
To avoid the confusion, make suspend_enter() return -EBUSY in that
case too.
Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
[ rjw: Subject and changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some of the system suspend diagnostic messages related to
suspend-to-idle refer to it as "freeze sleep" or "freeze state"
while the others say "suspend-to-idle". To reduce the possible
confusion that may result from that, refine the former either to
say "suspend to idle" too or to make it clearer that what is printed
is a state string written to /sys/power/state ("mem", "standby",
or "freeze").
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When CONFIG_PM_DEBUG=y, we provide a sysfs file (/sys/power/pm_test) for
selecting one of a few suspend test modes, where rather than entering a
full suspend state, the kernel will perform some subset of suspend
steps, wait 5 seconds, and then resume back to normal operation.
This mode is useful for (among other things) observing the state of the
system just before entering a sleep mode, for debugging or analysis
purposes. However, a constant 5 second wait is not sufficient for some
sorts of analysis; for example, on an SoC, one might want to use
external tools to probe the power states of various on-chip controllers
or clocks.
This patch turns this 5 second delay into a configurable module
parameter, so users can determine how long to wait in this
pseudo-suspend state before resuming the system.
Example (wait 30 seconds);
# echo 30 > /sys/module/suspend/parameters/pm_test_delay
# echo core > /sys/power/pm_test
# time echo mem > /sys/power/state
...
[ 17.583625] suspend debug: Waiting for 30 second(s).
...
real 0m30.381s
user 0m0.017s
sys 0m0.080s
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Kevin Cernekee <cernekee@chromium.org>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In preparation for adding support for quiescing timers in the final
stage of suspend-to-idle transitions, rework the freeze_enter()
function making the system wait on a wakeup event, the freeze_wake()
function terminating the suspend-to-idle loop and the mechanism by
which deep idle states are entered during suspend-to-idle.
First of all, introduce a simple state machine for suspend-to-idle
and make the code in question use it.
Second, prevent freeze_enter() from losing wakeup events due to race
conditions and ensure that the number of online CPUs won't change
while it is being executed. In addition to that, make it force
all of the CPUs re-enter the idle loop in case they are in idle
states already (so they can enter deeper idle states if possible).
Next, drop cpuidle_use_deepest_state() and replace use_deepest_state
checks in cpuidle_select() and cpuidle_reflect() with a single
suspend-to-idle state check in cpuidle_idle_call().
Finally, introduce cpuidle_enter_freeze() that will simply find the
deepest idle state available to the given CPU and enter it using
cpuidle_enter().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
If no freeze_ops is set, trying to enter suspend-to-IDLE will cause a
nice oops in platform_suspend_prepare_late(). Add respective checks to
platform_suspend_prepare_late() and platform_resume_early() functions.
Fixes: a8d46b9e4e (ACPI / sleep: Rework the handling of ACPI GPE wakeup ...)
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ACPI GPE wakeup from suspend-to-idle is currently based on using
the IRQF_NO_SUSPEND flag for the ACPI SCI, but that is problematic
for a couple of reasons. First, in principle the ACPI SCI may be
shared and IRQF_NO_SUSPEND does not really work well with shared
interrupts. Second, it may require the ACPI subsystem to special-case
the handling of device notifications depending on whether or not
they are received during suspend-to-idle in some places which would
lead to fragile code. Finally, it's better the handle ACPI wakeup
interrupts consistently with wakeup interrupts from other sources.
For this reason, remove the IRQF_NO_SUSPEND flag from the ACPI SCI
and use enable_irq_wake()/disable_irq_wake() with it instead, which
requires two additional platform hooks to be added to struct
platform_freeze_ops.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rename several local functions related to platform handling during
system suspend resume in suspend.c so that their names better
reflect their roles.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Subsequent change sets will add platform-related operations between
dpm_suspend_late() and dpm_suspend_noirq() as well as between
dpm_resume_noirq() and dpm_resume_early() in suspend_enter(), so
export these functions for suspend_enter() to be able to call them
separately and split the invocations of dpm_suspend_end() and
dpm_resume_start() in there accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch adds another suspend_resume trace event for analyze_suspend
to capture. The resume_console call can take several hundred milliseconds
if the printk buffer is full of debug info. The tool will now inform
testers of the wasted time and encourage them to disable it in
production builds.
Signed-off-by: Todd Brandt <todd.e.brandt@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
After commit d431cbc53c (PM / sleep: Simplify sleep states sysfs
interface code) the pm_states[] array is not populated initially,
which causes setup_test_suspend() to always fail and the suspend
testing during boot doesn't work any more.
Fix the problem by using pm_labels[] instead of pm_states[] in
setup_test_suspend() and storing a pointer to the label of the
sleep state to test rather than the number representing it,
because the connection between the state numbers and labels is
only established by suspend_set_ops().
Fixes: d431cbc53c (PM / sleep: Simplify sleep states sysfs interface code)
Reported-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- ACPICA update to upstream version 20140724. That includes
ACPI 5.1 material (support for the _CCA and _DSD predefined names,
changes related to the DMAR and PCCT tables and ARM support among
other things) and cleanups related to using ACPICA's header files.
A major part of it is related to acpidump and the core code used
by that utility. Changes from Bob Moore, David E Box, Lv Zheng,
Sascha Wildner, Tomasz Nowicki, Hanjun Guo.
- Radix trees for memory bitmaps used by the hibernation core from
Joerg Roedel.
- Support for waking up the system from suspend-to-idle (also known
as the "freeze" sleep state) using ACPI-based PCI wakeup signaling
(Rafael J Wysocki).
- Fixes for issues related to ACPI button events (Rafael J Wysocki).
- New device ID for an ACPI-enumerated device included into the
Wildcat Point PCH from Jie Yang.
- ACPI video updates related to backlight handling from Hans de Goede
and Linus Torvalds.
- Preliminary changes needed to support ACPI on ARM from Hanjun Guo
and Graeme Gregory.
- ACPI PNP core cleanups from Arjun Sreedharan and Zhang Rui.
- Cleanups related to ACPI_COMPANION() and ACPI_HANDLE() macros
(Rafael J Wysocki).
- ACPI-based device hotplug cleanups from Wei Yongjun and
Rafael J Wysocki.
- Cleanups and improvements related to system suspend from
Lan Tianyu, Randy Dunlap and Rafael J Wysocki.
- ACPI battery cleanup from Wei Yongjun.
- cpufreq core fixes from Viresh Kumar.
- Elimination of a deadband effect from the cpufreq ondemand
governor and intel_pstate driver cleanups from Stratos Karafotis.
- 350MHz CPU support for the powernow-k6 cpufreq driver from
Mikulas Patocka.
- Fix for the imx6 cpufreq driver from Anson Huang.
- cpuidle core and governor cleanups from Daniel Lezcano,
Sandeep Tripathy and Mohammad Merajul Islam Molla.
- Build fix for the big_little cpuidle driver from Sachin Kamat.
- Configuration fix for the Operation Performance Points (OPP)
framework from Mark Brown.
- APM cleanup from Jean Delvare.
- cpupower utility fixes and cleanups from Peter Senna Tschudin,
Andrey Utkin, Himangi Saraogi, Rickard Strandqvist, Thomas Renninger.
/
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Merge tag 'pm+acpi-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management updates from Rafael Wysocki:
"Again, ACPICA leads the pack (47 commits), followed by cpufreq (18
commits) and system suspend/hibernation (9 commits).
From the new code perspective, the ACPICA update brings ACPI 5.1 to
the table, including a new device configuration object called _DSD
(Device Specific Data) that will hopefully help us to operate device
properties like Device Trees do (at least to some extent) and changes
related to supporting ACPI on ARM.
Apart from that we have hibernation changes making it use radix trees
to store memory bitmaps which should speed up some operations carried
out by it quite significantly. We also have some power management
changes related to suspend-to-idle (the "freeze" sleep state) support
and more preliminary changes needed to support ACPI on ARM (outside of
ACPICA).
The rest is fixes and cleanups pretty much everywhere.
Specifics:
- ACPICA update to upstream version 20140724. That includes ACPI 5.1
material (support for the _CCA and _DSD predefined names, changes
related to the DMAR and PCCT tables and ARM support among other
things) and cleanups related to using ACPICA's header files. A
major part of it is related to acpidump and the core code used by
that utility. Changes from Bob Moore, David E Box, Lv Zheng,
Sascha Wildner, Tomasz Nowicki, Hanjun Guo.
- Radix trees for memory bitmaps used by the hibernation core from
Joerg Roedel.
- Support for waking up the system from suspend-to-idle (also known
as the "freeze" sleep state) using ACPI-based PCI wakeup signaling
(Rafael J Wysocki).
- Fixes for issues related to ACPI button events (Rafael J Wysocki).
- New device ID for an ACPI-enumerated device included into the
Wildcat Point PCH from Jie Yang.
- ACPI video updates related to backlight handling from Hans de Goede
and Linus Torvalds.
- Preliminary changes needed to support ACPI on ARM from Hanjun Guo
and Graeme Gregory.
- ACPI PNP core cleanups from Arjun Sreedharan and Zhang Rui.
- Cleanups related to ACPI_COMPANION() and ACPI_HANDLE() macros
(Rafael J Wysocki).
- ACPI-based device hotplug cleanups from Wei Yongjun and Rafael J
Wysocki.
- Cleanups and improvements related to system suspend from Lan
Tianyu, Randy Dunlap and Rafael J Wysocki.
- ACPI battery cleanup from Wei Yongjun.
- cpufreq core fixes from Viresh Kumar.
- Elimination of a deadband effect from the cpufreq ondemand governor
and intel_pstate driver cleanups from Stratos Karafotis.
- 350MHz CPU support for the powernow-k6 cpufreq driver from Mikulas
Patocka.
- Fix for the imx6 cpufreq driver from Anson Huang.
- cpuidle core and governor cleanups from Daniel Lezcano, Sandeep
Tripathy and Mohammad Merajul Islam Molla.
- Build fix for the big_little cpuidle driver from Sachin Kamat.
- Configuration fix for the Operation Performance Points (OPP)
framework from Mark Brown.
- APM cleanup from Jean Delvare.
- cpupower utility fixes and cleanups from Peter Senna Tschudin,
Andrey Utkin, Himangi Saraogi, Rickard Strandqvist, Thomas
Renninger"
* tag 'pm+acpi-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (118 commits)
ACPI / LPSS: add LPSS device for Wildcat Point PCH
ACPI / PNP: Replace faulty is_hex_digit() by isxdigit()
ACPICA: Update version to 20140724.
ACPICA: ACPI 5.1: Update for PCCT table changes.
ACPICA/ARM: ACPI 5.1: Update for GTDT table changes.
ACPICA/ARM: ACPI 5.1: Update for MADT changes.
ACPICA/ARM: ACPI 5.1: Update for FADT changes.
ACPICA: ACPI 5.1: Support for the _CCA predifined name.
ACPICA: ACPI 5.1: New notify value for System Affinity Update.
ACPICA: ACPI 5.1: Support for the _DSD predefined name.
ACPICA: Debug object: Add current value of Timer() to debug line prefix.
ACPICA: acpihelp: Add UUID support, restructure some existing files.
ACPICA: Utilities: Fix local printf issue.
ACPICA: Tables: Update for DMAR table changes.
ACPICA: Remove some extraneous printf arguments.
ACPICA: Update for comments/formatting. No functional changes.
ACPICA: Disassembler: Add support for the ToUUID opererator (macro).
ACPICA: Remove a redundant cast to acpi_size for ACPI_OFFSET() macro.
ACPICA: Work around an ancient GCC bug.
ACPI / processor: Make it possible to get local x2apic id via _MAT
...
to the ftrace function callback infrastructure. It's introducing a
way to allow different functions to call directly different trampolines
instead of all calling the same "mcount" one.
The only user of this for now is the function graph tracer, which always
had a different trampoline, but the function tracer trampoline was called
and did basically nothing, and then the function graph tracer trampoline
was called. The difference now, is that the function graph tracer
trampoline can be called directly if a function is only being traced by
the function graph trampoline. If function tracing is also happening on
the same function, the old way is still done.
The accounting for this takes up more memory when function graph tracing
is activated, as it needs to keep track of which functions it uses.
I have a new way that wont take as much memory, but it's not ready yet
for this merge window, and will have to wait for the next one.
Another big change was the removal of the ftrace_start/stop() calls that
were used by the suspend/resume code that stopped function tracing when
entering into suspend and resume paths. The stop of ftrace was done
because there was some function that would crash the system if one called
smp_processor_id()! The stop/start was a big hammer to solve the issue
at the time, which was when ftrace was first introduced into Linux.
Now ftrace has better infrastructure to debug such issues, and I found
the problem function and labeled it with "notrace" and function tracing
can now safely be activated all the way down into the guts of suspend
and resume.
Other changes include clean ups of uprobe code.
Clean up of the trace_seq() code.
And other various small fixes and clean ups to ftrace and tracing.
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Merge tag 'trace-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"This pull request has a lot of work done. The main thing is the
changes to the ftrace function callback infrastructure. It's
introducing a way to allow different functions to call directly
different trampolines instead of all calling the same "mcount" one.
The only user of this for now is the function graph tracer, which
always had a different trampoline, but the function tracer trampoline
was called and did basically nothing, and then the function graph
tracer trampoline was called. The difference now, is that the
function graph tracer trampoline can be called directly if a function
is only being traced by the function graph trampoline. If function
tracing is also happening on the same function, the old way is still
done.
The accounting for this takes up more memory when function graph
tracing is activated, as it needs to keep track of which functions it
uses. I have a new way that wont take as much memory, but it's not
ready yet for this merge window, and will have to wait for the next
one.
Another big change was the removal of the ftrace_start/stop() calls
that were used by the suspend/resume code that stopped function
tracing when entering into suspend and resume paths. The stop of
ftrace was done because there was some function that would crash the
system if one called smp_processor_id()! The stop/start was a big
hammer to solve the issue at the time, which was when ftrace was first
introduced into Linux. Now ftrace has better infrastructure to debug
such issues, and I found the problem function and labeled it with
"notrace" and function tracing can now safely be activated all the way
down into the guts of suspend and resume
Other changes include clean ups of uprobe code, clean up of the
trace_seq() code, and other various small fixes and clean ups to
ftrace and tracing"
* tag 'trace-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (57 commits)
ftrace: Add warning if tramp hash does not match nr_trampolines
ftrace: Fix trampoline hash update check on rec->flags
ring-buffer: Use rb_page_size() instead of open coded head_page size
ftrace: Rename ftrace_ops field from trampolines to nr_trampolines
tracing: Convert local function_graph functions to static
ftrace: Do not copy old hash when resetting
tracing: let user specify tracing_thresh after selecting function_graph
ring-buffer: Always run per-cpu ring buffer resize with schedule_work_on()
tracing: Remove function_trace_stop and HAVE_FUNCTION_TRACE_MCOUNT_TEST
s390/ftrace: remove check of obsolete variable function_trace_stop
arm64, ftrace: Remove check of obsolete variable function_trace_stop
Blackfin: ftrace: Remove check of obsolete variable function_trace_stop
metag: ftrace: Remove check of obsolete variable function_trace_stop
microblaze: ftrace: Remove check of obsolete variable function_trace_stop
MIPS: ftrace: Remove check of obsolete variable function_trace_stop
parisc: ftrace: Remove check of obsolete variable function_trace_stop
sh: ftrace: Remove check of obsolete variable function_trace_stop
sparc64,ftrace: Remove check of obsolete variable function_trace_stop
tile: ftrace: Remove check of obsolete variable function_trace_stop
ftrace: x86: Remove check of obsolete variable function_trace_stop
...
After the introduction of freeze_ops it makes more sense to move
all of the platform suspend operations to separate functions that
each will do all of the necessary checks and choose the right
callback to execute istead of doing all that in the core code
which makes it generally harder to follow.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Simplify the sleep states sysfs interface /sys/power/state code by
redefining pm_states[] as an array of pointers to constant strings
such that only the entries corresponding to valid states are set.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ftrace_stop() and ftrace_start() were added to the suspend and hibernate
process because there was some function within the work flow that caused
the system to reboot if it was traced. This function has recently been
found (restore_processor_state()). Now there's no reason to disable
function tracing while we are going into suspend or hibernate, which means
that being able to trace this will help tremendously in debugging any
issues with suspend or hibernate.
This also means that the ftrace_stop/start() functions can be removed
and simplify the function tracing code a bit.
Link: http://lkml.kernel.org/r/1518201.VD9cU33jRU@vostro.rjw.lan
Acked-by: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
