There were a few files in the driver core power code that did not have
SPDX identifiers on them, so fix that up. At the same time, remove the
"free form" text that specified the license of the file, as that is
impossible for any tool to properly parse.
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- Fix registration of new cpuidle governors partially broken during
the 5.0 development cycle by mistake (Rafael Wysocki).
- Avoid integer overflows in the menu cpuidle governor by making
it discard the overflowing data points upfront (Rafael Wysocki).
- Fix minor mistake in the recent update of the iowait boost
computation in the intel_pstate driver (Rafael Wysocki).
- Drop incorrect __init annotation from one function in the pxa2xx
cpufreq driver (Arnd Bergmann).
- Fix the operating performance points (OPP) framework
initialization for devices in multiple power domains if
only one of them is scalable (Rajendra Nayak).
- Fix mistake in dev_pm_opp_set_rate() which causes it to skip
updating the performance state if the new frequency is the same
as the old one (Viresh Kumar).
- Rework the cancellation of wakeup source timers to avoid
potential issues with it and do some cleanups unlocked by
that change (Viresh Kumar, Rafael Wysocki).
- Clean up the code computing the active/suspended time of devices
in the PM-runtime framework after recent changes (Ulf Hansson).
- Make the power management infrastructure code use pr_fmt()
consistently (Joe Perches).
- Clean up the generic power domains (genpd) framework somewhat
(Aisheng Dong).
- Improve kerneldoc comments for two functions in the cpufreq core
(Rafael Wysocki).
- Fix typo in a PM QoS file description comment (Aisheng Dong).
- Update the handling of CPU boost frequencies in the cpupower
utility (Abhishek Goel).
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Merge tag 'pm-5.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management updates from Rafael Wysocki:
"These are mostly fixes and cleanups on top of the previously merged
power management material for 5.1-rc1 with one cpupower utility update
that wasn't pushed earlier due to unfortunate timing.
Specifics:
- Fix registration of new cpuidle governors partially broken during
the 5.0 development cycle by mistake (Rafael Wysocki).
- Avoid integer overflows in the menu cpuidle governor by making it
discard the overflowing data points upfront (Rafael Wysocki).
- Fix minor mistake in the recent update of the iowait boost
computation in the intel_pstate driver (Rafael Wysocki).
- Drop incorrect __init annotation from one function in the pxa2xx
cpufreq driver (Arnd Bergmann).
- Fix the operating performance points (OPP) framework initialization
for devices in multiple power domains if only one of them is
scalable (Rajendra Nayak).
- Fix mistake in dev_pm_opp_set_rate() which causes it to skip
updating the performance state if the new frequency is the same as
the old one (Viresh Kumar).
- Rework the cancellation of wakeup source timers to avoid potential
issues with it and do some cleanups unlocked by that change (Viresh
Kumar, Rafael Wysocki).
- Clean up the code computing the active/suspended time of devices in
the PM-runtime framework after recent changes (Ulf Hansson).
- Make the power management infrastructure code use pr_fmt()
consistently (Joe Perches).
- Clean up the generic power domains (genpd) framework somewhat
(Aisheng Dong).
- Improve kerneldoc comments for two functions in the cpufreq core
(Rafael Wysocki).
- Fix typo in a PM QoS file description comment (Aisheng Dong).
- Update the handling of CPU boost frequencies in the cpupower
utility (Abhishek Goel)"
* tag 'pm-5.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpuidle: governor: Add new governors to cpuidle_governors again
cpufreq: intel_pstate: Fix up iowait_boost computation
PM / OPP: Update performance state when freq == old_freq
PM / wakeup: Drop wakeup_source_drop()
PM / wakeup: Rework wakeup source timer cancellation
PM / domains: Remove one unnecessary blank line
PM / Domains: Return early for all errors in _genpd_power_off()
PM / Domains: Improve warn for multiple states but no governor
OPP: Fix handling of multiple power domains
PM / QoS: Fix typo in file description
cpufreq: pxa2xx: remove incorrect __init annotation
PM-runtime: Call pm_runtime_active|suspended_time() from sysfs
PM-runtime: Consolidate code to get active/suspended time
PM: Add and use pr_fmt()
cpufreq: Improve kerneldoc comments for cpufreq_cpu_get/put()
cpuidle: menu: Avoid overflows when computing variance
tools/power/cpupower: Display boost frequency separately
Avoid the open-coding of the accounted time acquisition in
runtime_active|suspend_time_show() and make them call
pm_runtime_active|suspended_time() instead.
Note that this change also indirectly avoids holding dev->power.lock
around the do_div() computation and the sprintf() call which is an
additional improvement.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In a step to consolidate the code for fetching the PM-runtime
active/suspended time for a device, add a common function for that
and make the existing pm_runtime_suspended_time() call it.
Also add a corresponding pm_runtime_active_time() calling the new
common function.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
[ rjw: Changelog, function rename ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Here is the big driver core patchset for 5.1-rc1
More patches than "normal" here this merge window, due to some work in
the driver core by Alexander Duyck to rework the async probe
functionality to work better for a number of devices, and independant
work from Rafael for the device link functionality to make it work
"correctly".
Also in here is:
- lots of BUS_ATTR() removals, the macro is about to go away
- firmware test fixups
- ihex fixups and simplification
- component additions (also includes i915 patches)
- lots of minor coding style fixups and cleanups.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the big driver core patchset for 5.1-rc1
More patches than "normal" here this merge window, due to some work in
the driver core by Alexander Duyck to rework the async probe
functionality to work better for a number of devices, and independant
work from Rafael for the device link functionality to make it work
"correctly".
Also in here is:
- lots of BUS_ATTR() removals, the macro is about to go away
- firmware test fixups
- ihex fixups and simplification
- component additions (also includes i915 patches)
- lots of minor coding style fixups and cleanups.
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (65 commits)
driver core: platform: remove misleading err_alloc label
platform: set of_node in platform_device_register_full()
firmware: hardcode the debug message for -ENOENT
driver core: Add missing description of new struct device_link field
driver core: Fix PM-runtime for links added during consumer probe
drivers/component: kerneldoc polish
async: Add cmdline option to specify drivers to be async probed
driver core: Fix possible supplier PM-usage counter imbalance
PM-runtime: Fix __pm_runtime_set_status() race with runtime resume
driver: platform: Support parsing GpioInt 0 in platform_get_irq()
selftests: firmware: fix verify_reqs() return value
Revert "selftests: firmware: remove use of non-standard diff -Z option"
Revert "selftests: firmware: add CONFIG_FW_LOADER_USER_HELPER_FALLBACK to config"
device: Fix comment for driver_data in struct device
kernfs: Allocating memory for kernfs_iattrs with kmem_cache.
sysfs: remove unused include of kernfs-internal.h
driver core: Postpone DMA tear-down until after devres release
driver core: Document limitation related to DL_FLAG_RPM_ACTIVE
PM-runtime: Take suppliers into account in __pm_runtime_set_status()
device.h: Add __cold to dev_<level> logging functions
...
When rpm_resume() desactivates the autosuspend timer, it should only
try to cancel hrtimer but not wait for the handler to finish, because
both rpm_resume() and pm_suspend_timer_fn() take the power.lock.
A deadlock is possible as follows:
CPU0 CPU1
rpm_resume()
spin_lock_irqsave
pm_suspend_timer_fn()
spin_lock_irqsave
pm_runtime_deactivate_timer()
hrtimer_cancel()
It is sufficient to call hrtimer_try_to_cancel() from
pm_runtime_deactivate_timer(), because dev->power.timer_expires
reset to 0 by it, so use that function instead of hrtimer_cancel().
Fixes: 8234f6734c ("PM-runtime: Switch autosuspend over to using hrtimers")
Reported-by: Sunzhaosheng Sun(Zhaosheng) <sunzhaosheng@hisilicon.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 4c06c4e6cf ("driver core: Fix possible supplier PM-usage
counter imbalance") introduced a regression that causes suppliers
to be suspended prematurely for device links added during consumer
driver probe if the initial PM-runtime status of the consumer is
"suspended" and the consumer is resumed after adding the link and
before pm_runtime_put_suppliers() is called. In that case,
pm_runtime_put_suppliers() will drop the rpm_active refcount for
the link by one and (since rpm_active is equal to two after the
preceding consumer resume) the supplier's PM-runtime usage counter
will be decremented, which may cause the supplier to suspend even
though the consumer's PM-runtime status is "active".
For this reason, partially revert commit 4c06c4e6cf as the problem
it tried to fix needs to be addressed somewhat differently, and
change pm_runtime_get_suppliers() and pm_runtime_put_suppliers() so
that the latter only drops rpm_active references acquired by the
former. [This requires adding a new field to struct device_link,
but I coulnd't find a cleaner way to address the issue that would
work in all cases.]
This causes pm_runtime_put_suppliers() to effectively ignore device
links added during consumer probe, so device_link_add() doesn't need
to worry about ensuring that suppliers will remain active after
pm_runtime_put_suppliers() for links created with DL_FLAG_RPM_ACTIVE
set and it only needs to bump up rpm_active by one for those links,
so pm_runtime_active_link() is not necessary any more.
Fixes: 4c06c4e6cf ("driver core: Fix possible supplier PM-usage counter imbalance")
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a stateless device link to a certain supplier with
DL_FLAG_PM_RUNTIME set in the flags is added and then removed by the
consumer driver's probe callback, the supplier's PM-runtime usage
counter will be nonzero after that which effectively causes the
supplier to remain "always on" going forward.
Namely, device_link_add() called to add the link invokes
device_link_rpm_prepare() which notices that the consumer driver is
probing, so it increments the supplier's PM-runtime usage counter
with the assumption that the link will stay around until
pm_runtime_put_suppliers() is called by driver_probe_device(),
but if the link goes away before that point, the supplier's
PM-runtime usage counter will remain nonzero.
To prevent that from happening, first rework pm_runtime_get_suppliers()
and pm_runtime_put_suppliers() to use the rpm_active refounts of device
links and make the latter only drop rpm_active and the supplier's
PM-runtime usage counter for each link by one, unless rpm_active is
one already for it. Next, modify device_link_add() to bump up the
new link's rpm_active refcount and the suppliers PM-runtime usage
counter by two, to prevent pm_runtime_put_suppliers(), if it is
called subsequently, from suspending the supplier prematurely (in
case its PM-runtime usage counter goes down to 0 in there).
Due to the way rpm_put_suppliers() works, this change does not
affect runtime suspend of the consumer ends of new device links (or,
generally, device links for which DL_FLAG_PM_RUNTIME has just been
set).
Fixes: e2f3cd831a ("driver core: Fix handling of runtime PM flags in device_link_add()")
Reported-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 4080ab0830 ("PM-runtime: Take suppliers into account in
__pm_runtime_set_status()") introduced a race condition that may
trigger if __pm_runtime_set_status() is used incorrectly (that is,
if it is called when PM-runtime is enabled for the target device
and working).
In that case, if the original PM-runtime status of the device is
RPM_SUSPENDED, a runtime resume of the device may occur after
__pm_runtime_set_status() has dropped its power.lock spinlock
and before deactivating its suppliers, so the suppliers may be
deactivated while the device is PM-runtime-active which may lead
to functional issues.
To avoid that, modify __pm_runtime_set_status() to check whether
or not PM-runtime is enabled for the device before activating its
suppliers (if the new status is RPM_ACTIVE) and either return an
error if that's the case or increment the device's disable_depth
counter to prevent PM-runtime from being enabled for it while
the remaining part of the function is running (disable_depth is
then decremented on the way out).
Fixes: 4080ab0830 ("PM-runtime: Take suppliers into account in __pm_runtime_set_status()")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the target device has any suppliers, as reflected by device links
to them, __pm_runtime_set_status() does not take them into account,
which is not consistent with the other parts of the PM-runtime
framework and may lead to programming mistakes.
Modify __pm_runtime_set_status() to take suppliers into account by
activating them upfront if the new status is RPM_ACTIVE and
deactivating them on exit if the new status is RPM_SUSPENDED.
If the activation of one of the suppliers fails, the new status
will be RPM_SUSPENDED and the (remaining) suppliers will be
deactivated on exit (the child count of the device's parent
will be dropped too then).
Of course, adding device links locking to __pm_runtime_set_status()
means that it cannot be run fron interrupt context, so make it use
spin_lock_irq() and spin_unlock_irq() instead of spin_lock_irqsave()
and spin_unlock_irqrestore(), respectively.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Update the accounting_timestamp field only when PM runtime is enabled
and don't forget to account the last state before disabling it.
Suggested-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
[ rjw: Minor cleanups ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Similar to what happened whith autosuspend, a deadlock has been
reported with PM-runtime accounting in the call path:
change_clocksource
...
write_seqcount_begin
...
timekeeping_update
...
sh_cmt_clocksource_enable
...
rpm_resume
update_pm_runtime_accounting
ktime_get
do
read_seqcount_begin
while read_seqcount_retry
....
write_seqcount_end
Make PM-runtime accounting use ktime_get_mono_fast_ns() to avoid this
problem.
With ktime_get_mono_fast_ns(), the timestamp is not guaranteed to be
monotonic across an update of timekeeping and as a result time can go
backward. Add a test to skip accounting for such situation which should
stay exceptional.
Fixes: a08c2a5a31 ("PM-runtime: Replace jiffies-based accounting with ktime-based accounting")
Reported-by: Biju Das <biju.das@bp.renesas.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
[ rjw: Subject, changelog, comment cleanup ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
pm_runtime_autosuspend_expiration calls ktime_get_mono_fast_ns()
even when its returned value may be unused. Therefore get the
current time later and remove gotos while there.
Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Calling rpm_put_suppliers() from pm_runtime_drop_link() is excessive
as it affects all suppliers of the consumer device and not just the
one pointed to by the device link being dropped. Worst case it may
cause the consumer device to stop working unexpectedly. Moreover, in
principle it is racy with respect to runtime PM of the consumer
device.
To avoid these problems drop runtime PM references on the particular
supplier pointed to by the link in question only and do that after
the link has been dropped from the consumer device's list of links to
suppliers, which is in device_link_free().
Fixes: a0504aecba ("PM / runtime: Drop usage count for suppliers at device link removal")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After commit ead18c23c2 ("driver core: Introduce device links
reference counting"), if there is a link between the given supplier
and the given consumer already, device_link_add() will refcount it
and return it unconditionally without updating its flags. It is
possible, however, that the second (or any subsequent) caller of
device_link_add() for the same consumer-supplier pair will pass
DL_FLAG_PM_RUNTIME, possibly along with DL_FLAG_RPM_ACTIVE, in flags
to it and the existing link may not behave as expected then.
First, if DL_FLAG_PM_RUNTIME is not set in the existing link's flags
at all, it needs to be set like during the original initialization of
the link.
Second, if DL_FLAG_RPM_ACTIVE is passed to device_link_add() in flags
(in addition to DL_FLAG_PM_RUNTIME), the existing link should to be
updated to reflect the "active" runtime PM configuration of the
consumer-supplier pair and extra care must be taken here to avoid
possible destructive races with runtime PM of the consumer.
To that end, redefine the rpm_active field in struct device_link
as a refcount, initialize it to 1 and make rpm_resume() (for the
consumer) and device_link_add() increment it whenever they acquire
a runtime PM reference on the supplier device. Accordingly, make
rpm_suspend() (for the consumer) and pm_runtime_clean_up_links()
decrement it and drop runtime PM references to the supplier
device in a loop until rpm_active becones 1 again.
Fixes: ead18c23c2 ("driver core: Introduce device links reference counting")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace jiffies-based accounting for runtime_active_time and
runtime_suspended_time with ktime-based accounting. This makes the
runtime debug counters inline with genpd and other PM subsytems which
use ktime-based accounting.
Timekeeping is initialized before driver_init(). It's only at that time
that PM-runtime can be enabled.
Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
[switch from ktime to raw nsec]
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Initializing accounting_timestamp to something different from 0 during
pm_runtime_init() doesn't make sense and puts an artificial ordering
constraint between timekeeping_init() and pm_runtime_init().
PM-runtime should start time accounting only when it is enabled and
discard the period when disabled.
Set accounting_timestamp to now when enabling PM-runtime.
Suggested-by: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
A deadlock has been seen when swicthing clocksources which use
PM-runtime. The call path is:
change_clocksource
...
write_seqcount_begin
...
timekeeping_update
...
sh_cmt_clocksource_enable
...
rpm_resume
pm_runtime_mark_last_busy
ktime_get
do
read_seqcount_begin
while read_seqcount_retry
....
write_seqcount_end
Although we should be safe because we haven't yet changed the
clocksource at that time, we can't do that because of seqcount
protection.
Use ktime_get_mono_fast_ns() instead which is lock safe for such
cases.
With ktime_get_mono_fast_ns, the timestamp is not guaranteed to be
monotonic across an update and as a result can goes backward.
According to update_fast_timekeeper() description: "In the worst
case, this can result is a slightly wrong timestamp (a few
nanoseconds)". For PM-runtime autosuspend, this means only that
the suspend decision may be slightly suboptimal.
Fixes: 8234f6734c ("PM-runtime: Switch autosuspend over to using hrtimers")
Reported-by: Biju Das <biju.das@bp.renesas.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some drivers (like i915/drm) needs to get the accounted suspended time.
pm_runtime_suspended_time() will return the suspended accounted time
in ns unit.
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cast autosuspend_delay to u64 to make sure that the full computation
of 'expires' or slack will be done in u64, even on 32bits arch.
Otherwise, any delay greater than 2^31 nsec can overflow if signed
32bits is used when converting delay from msec to nsec.
Fixes: 8234f6734c (PM-runtime: Switch autosuspend over to using hrtimers)
Reported-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM-runtime now uses the hrtimers infrastructure for autosuspend, however
comments still reference 'jiffies'.
Fixes: 8234f6734c (PM-runtime: Switch autosuspend over to using hrtimers)
Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM-runtime uses the timer infrastructure for autosuspend. This implies
that the minimum time before autosuspending a device is in the range
of 1 tick included to 2 ticks excluded
-On arm64 this means between 4ms and 8ms with default jiffies
configuration
-And on arm, it is between 10ms and 20ms
These values are quite high for embedded systems which sometimes want
the duration to be in the range of 1 ms.
It is possible to switch autosuspend over to using hrtimers to get
finer granularity for short durations and take advantage of slack to
retain some margins and get long timeouts with minimum wakeups.
On an arm64 platform that uses 1ms for autosuspending timeout of its
GPU, idle power is reduced by 10% with hrtimer.
The latency impact on arm64 hikey octo cores is:
- mark_last_busy: from 1.11 us to 1.25 us
- rpm_suspend: from 15.54 us to 15.38 us
[Only the code path of rpm_suspend() that starts hrtimer has been
measured.]
arm64 image (arm64 default defconfig) decreases by around 3KB
with following details:
$ size vmlinux-timer
text data bss dec hex filename
12034646 6869268 386840 19290754 1265a82 vmlinux
$ size vmlinux-hrtimer
text data bss dec hex filename
12030550 6870164 387032 19287746 1264ec2 vmlinux
The latency impact on arm 32bits snowball dual cores is :
- mark_last_busy: from 0.31 us usec to 0.77 us
- rpm_suspend: from 6.83 us to 6.67 usec
The increase of the image for snowball platform that I used for
testing performance impact, is neglictable (244B).
$ size vmlinux-timer
text data bss dec hex filename
7157961 2119580 264120 9541661 91981d build-ux500/vmlinux
size vmlinux-hrtimer
text data bss dec hex filename
7157773 2119884 264248 9541905 919911 vmlinux-hrtimer
And arm 32bits image (multi_v7_defconfig) increases by around 1.7KB
with following details:
$ size vmlinux-timer
text data bss dec hex filename
13304443 6803420 402768 20510631 138f7a7 vmlinux
$ size vmlinux-hrtimer
text data bss dec hex filename
13304299 6805276 402768 20512343 138fe57 vmlinux
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Revert commit 1e83786198 (PM / runtime: Fixup reference counting of
device link suppliers at probe), as it has introduced a regression
and the condition it was designed to address should be covered by the
existing code.
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In the case consumer device is runtime resumed, while the link to the
supplier is removed, the earlier call to pm_runtime_get_sync() made from
rpm_get_suppliers() does not get properly balanced with a corresponding
call to pm_runtime_put(). This leads to that suppliers remains to be
runtime resumed forever, while they don't need to.
Let's fix the behaviour by calling rpm_put_suppliers() when dropping a
device link. Not that, since rpm_put_suppliers() checks the
link->rpm_active flag, we can correctly avoid to call pm_runtime_put() in
cases when we shouldn't.
Reported-by: Todor Tomov <todor.tomov@linaro.org>
Fixes: 21d5c57b37 (PM / runtime: Use device links)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In the driver core, before it invokes really_probe() it runtime resumes the
suppliers for the device via calling pm_runtime_get_suppliers(), which also
increases the runtime PM usage count for each of the available supplier.
This makes sense, as to be able to allow the consumer device to be probed
by its driver. However, if the driver decides to add a new supplier link
during ->probe(), hence updating the list of suppliers, the following call
to pm_runtime_put_suppliers(), invoked after really_probe() in the driver
core, we get into trouble.
More precisely, pm_runtime_put() gets called also for the new supplier(s),
which is wrong as the driver core, didn't trigger pm_runtime_get_sync() to
be called for it in the first place. In other words, the new supplier may
be runtime suspended even in cases when it shouldn't.
Fix this behaviour, by runtime resume suppliers according to the same
conditions as managed by the runtime PM core, when runtime resume callbacks
are being invoked.
Additionally, don't try to runtime suspend any of the suppliers after
really_probe(), but instead rely on that to happen via the consumer device,
when it becomes runtime suspended.
Fixes: 21d5c57b37 (PM / runtime: Use device links)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The pm_runtime_force_suspend|resume() helpers currently requires the device
to at some level (PM domain, bus, etc), have the ->runtime_suspend|resume()
callbacks assigned for it, else -ENOSYS is returned as an error.
However, there are no reason for this requirement, so let's simply remove
it by allowing these callbacks to be NULL.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Modify pm_runtime_need_not_resume() to make it avoid taking
power.child_count for devices with power.ignore_children which
is consistent with the runtime PM usage of these fields.
Suggested-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
One of the limitations of pm_runtime_force_suspend/resume() is that
if a parent driver wants to use these functions, all of its child
drivers generally have to do that too because of the parent usage
counter manipulations necessary to get the correct state of the parent
during system-wide transitions to the working state (system resume).
However, that limitation turns out to be artificial, so remove it.
Namely, pm_runtime_force_suspend() only needs to update the children
counter of its parent (if there's is a parent) when the device can
stay in suspend after the subsequent system resume transition, as
that counter is correct already otherwise. Now, if the parent's
children counter is not updated, it is not necessary to increment
the parent's usage counter in that case any more, as long as the
children counters of devices are checked along with their usage
counters in order to decide whether or not the devices may be left
in suspend after the subsequent system resume transition.
Accordingly, modify pm_runtime_force_suspend() to only call
pm_runtime_set_suspended() for devices whose usage and children
counters are at the "no references" level (the runtime PM status
of the device needs to be updated to "suspended" anyway in case
this function is called once again for the same device during the
transition under way), drop the parent usage counter incrementation
from it and update pm_runtime_force_resume() to compensate for these
changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Prevent rpm_get_suppliers() from returning an error code if runtime
PM is disabled for one or more of the supplier devices it wants to
runtime-resume, so as to make runtime PM work for devices with links
to suppliers that don't use runtime PM (such links may be created
during device enumeration even before it is known whether or not
runtime PM will be enabled for the devices in question, for example).
Fixes: 21d5c57b37 (PM / runtime: Use device links)
Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Adrian Hunter <adrian.hunter@intel.com>
The check for "active" children in __pm_runtime_set_status(), when
trying to set the parent device status to "suspended", doesn't
really make sense, because in fact it is not invalid to set the
status of a device with runtime PM disabled to "suspended" in any
case. It is invalid to enable runtime PM for a device with its
status set to "suspended" while its child_count reference counter
is nonzero, but the check in __pm_runtime_set_status() doesn't
really cover that situation.
For this reason, drop the children check from __pm_runtime_set_status()
and add a check against child_count reference counters of "suspended"
devices to pm_runtime_enable().
Fixes: a8636c8964 (PM / Runtime: Don't allow to suspend a device with an active child)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Johan Hovold <johan@kernel.org>
- Relocate the OPP (Operating Performance Points) framework to its
own directory under drivers/ and add support for power domain
performance states to it (Viresh Kumar).
- Modify the PM core, the PCI bus type and the ACPI PM domain to
support power management driver flags allowing device drivers to
specify their capabilities and preferences regarding the handling
of devices with enabled runtime PM during system suspend/resume
and clean up that code somewhat (Rafael Wysocki, Ulf Hansson).
- Add frequency-invariant accounting support to the task scheduler
on ARM and ARM64 (Dietmar Eggemann).
- Fix PM QoS device resume latency framework to prevent "no
restriction" requests from overriding requests with specific
requirements and drop the confusing PM_QOS_FLAG_REMOTE_WAKEUP
device PM QoS flag (Rafael Wysocki).
- Drop legacy class suspend/resume operations from the PM core
and drop legacy bus type suspend and resume callbacks from
ARM/locomo (Rafael Wysocki).
- Add min/max frequency support to devfreq and clean it up
somewhat (Chanwoo Choi).
- Rework wakeup support in the generic power domains (genpd)
framework and update some of its users accordingly (Geert
Uytterhoeven).
- Convert timers in the PM core to use timer_setup() (Kees Cook).
- Add support for exposing the SLP_S0 (Low Power S0 Idle)
residency counter based on the LPIT ACPI table on Intel
platforms (Srinivas Pandruvada).
- Add per-CPU PM QoS resume latency support to the ladder cpuidle
governor (Ramesh Thomas).
- Fix a deadlock between the wakeup notify handler and the
notifier removal in the ACPI core (Ville Syrjälä).
- Fix a cpufreq schedutil governor issue causing it to use
stale cached frequency values sometimes (Viresh Kumar).
- Fix an issue in the system suspend core support code causing
wakeup events detection to fail in some cases (Rajat Jain).
- Fix the generic power domains (genpd) framework to prevent
the PM core from using the direct-complete optimization with
it as that is guaranteed to fail (Ulf Hansson).
- Fix a minor issue in the cpuidle core and clean it up a bit
(Gaurav Jindal, Nicholas Piggin).
- Fix and clean up the intel_idle and ARM cpuidle drivers (Jason
Baron, Len Brown, Leo Yan).
- Fix a couple of minor issues in the OPP framework and clean it
up (Arvind Yadav, Fabio Estevam, Sudeep Holla, Tobias Jordan).
- Fix and clean up some cpufreq drivers and fix a minor issue in
the cpufreq statistics code (Arvind Yadav, Bhumika Goyal, Fabio
Estevam, Gautham Shenoy, Gustavo Silva, Marek Szyprowski, Masahiro
Yamada, Robert Jarzmik, Zumeng Chen).
- Fix minor issues in the system suspend and hibernation core, in
power management documentation and in the AVS (Adaptive Voltage
Scaling) framework (Helge Deller, Himanshu Jha, Joe Perches,
Rafael Wysocki).
- Fix some issues in the cpupower utility and document that Shuah
Khan is going to maintain it going forward (Prarit Bhargava,
Shuah Khan).
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Merge tag 'pm-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"There are no real big ticket items here this time.
The most noticeable change is probably the relocation of the OPP
(Operating Performance Points) framework to its own directory under
drivers/ as it has grown big enough for that. Also Viresh is now going
to maintain it and send pull requests for it to me, so you will see
this change in the git history going forward (but still not right
now).
Another noticeable set of changes is the modifications of the PM core,
the PCI subsystem and the ACPI PM domain to allow of more integration
between system-wide suspend/resume and runtime PM. For now it's just a
way to avoid resuming devices from runtime suspend unnecessarily
during system suspend (if the driver sets a flag to indicate its
readiness for that) and in the works is an analogous mechanism to
allow devices to stay suspended after system resume.
In addition to that, we have some changes related to supporting
frequency-invariant CPU utilization metrics in the scheduler and in
the schedutil cpufreq governor on ARM and changes to add support for
device performance states to the generic power domains (genpd)
framework.
The rest is mostly fixes and cleanups of various sorts.
Specifics:
- Relocate the OPP (Operating Performance Points) framework to its
own directory under drivers/ and add support for power domain
performance states to it (Viresh Kumar).
- Modify the PM core, the PCI bus type and the ACPI PM domain to
support power management driver flags allowing device drivers to
specify their capabilities and preferences regarding the handling
of devices with enabled runtime PM during system suspend/resume and
clean up that code somewhat (Rafael Wysocki, Ulf Hansson).
- Add frequency-invariant accounting support to the task scheduler on
ARM and ARM64 (Dietmar Eggemann).
- Fix PM QoS device resume latency framework to prevent "no
restriction" requests from overriding requests with specific
requirements and drop the confusing PM_QOS_FLAG_REMOTE_WAKEUP
device PM QoS flag (Rafael Wysocki).
- Drop legacy class suspend/resume operations from the PM core and
drop legacy bus type suspend and resume callbacks from ARM/locomo
(Rafael Wysocki).
- Add min/max frequency support to devfreq and clean it up somewhat
(Chanwoo Choi).
- Rework wakeup support in the generic power domains (genpd)
framework and update some of its users accordingly (Geert
Uytterhoeven).
- Convert timers in the PM core to use timer_setup() (Kees Cook).
- Add support for exposing the SLP_S0 (Low Power S0 Idle) residency
counter based on the LPIT ACPI table on Intel platforms (Srinivas
Pandruvada).
- Add per-CPU PM QoS resume latency support to the ladder cpuidle
governor (Ramesh Thomas).
- Fix a deadlock between the wakeup notify handler and the notifier
removal in the ACPI core (Ville Syrjälä).
- Fix a cpufreq schedutil governor issue causing it to use stale
cached frequency values sometimes (Viresh Kumar).
- Fix an issue in the system suspend core support code causing wakeup
events detection to fail in some cases (Rajat Jain).
- Fix the generic power domains (genpd) framework to prevent the PM
core from using the direct-complete optimization with it as that is
guaranteed to fail (Ulf Hansson).
- Fix a minor issue in the cpuidle core and clean it up a bit (Gaurav
Jindal, Nicholas Piggin).
- Fix and clean up the intel_idle and ARM cpuidle drivers (Jason
Baron, Len Brown, Leo Yan).
- Fix a couple of minor issues in the OPP framework and clean it up
(Arvind Yadav, Fabio Estevam, Sudeep Holla, Tobias Jordan).
- Fix and clean up some cpufreq drivers and fix a minor issue in the
cpufreq statistics code (Arvind Yadav, Bhumika Goyal, Fabio
Estevam, Gautham Shenoy, Gustavo Silva, Marek Szyprowski, Masahiro
Yamada, Robert Jarzmik, Zumeng Chen).
- Fix minor issues in the system suspend and hibernation core, in
power management documentation and in the AVS (Adaptive Voltage
Scaling) framework (Helge Deller, Himanshu Jha, Joe Perches, Rafael
Wysocki).
- Fix some issues in the cpupower utility and document that Shuah
Khan is going to maintain it going forward (Prarit Bhargava, Shuah
Khan)"
* tag 'pm-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (88 commits)
tools/power/cpupower: add libcpupower.so.0.0.1 to .gitignore
tools/power/cpupower: Add 64 bit library detection
intel_idle: Graceful probe failure when MWAIT is disabled
cpufreq: schedutil: Reset cached_raw_freq when not in sync with next_freq
freezer: Fix typo in freezable_schedule_timeout() comment
PM / s2idle: Clear the events_check_enabled flag
cpufreq: stats: Handle the case when trans_table goes beyond PAGE_SIZE
cpufreq: arm_big_little: make cpufreq_arm_bL_ops structures const
cpufreq: arm_big_little: make function arguments and structure pointer const
cpuidle: Avoid assignment in if () argument
cpuidle: Clean up cpuidle_enable_device() error handling a bit
ACPI / PM: Fix acpi_pm_notifier_lock vs flush_workqueue() deadlock
PM / Domains: Fix genpd to deal with drivers returning 1 from ->prepare()
cpuidle: ladder: Add per CPU PM QoS resume latency support
PM / QoS: Fix device resume latency framework
PM / domains: Rework governor code to be more consistent
PM / Domains: Remove gpd_dev_ops.active_wakeup() callback
soc: rockchip: power-domain: Use GENPD_FLAG_ACTIVE_WAKEUP
soc: mediatek: Use GENPD_FLAG_ACTIVE_WAKEUP
ARM: shmobile: pm-rmobile: Use GENPD_FLAG_ACTIVE_WAKEUP
...
* pm-core:
ACPI / PM: Take SMART_SUSPEND driver flag into account
PCI / PM: Take SMART_SUSPEND driver flag into account
PCI / PM: Drop unnecessary invocations of pcibios_pm_ops callbacks
PM / core: Add SMART_SUSPEND driver flag
PCI / PM: Use the NEVER_SKIP driver flag
PM / core: Add NEVER_SKIP and SMART_PREPARE driver flags
PM / core: Convert timers to use timer_setup()
PM / core: Fix kerneldoc comments of four functions
PM / core: Drop legacy class suspend/resume operations
The special value of 0 for device resume latency PM QoS means
"no restriction", but there are two problems with that.
First, device resume latency PM QoS requests with 0 as the
value are always put in front of requests with positive
values in the priority lists used internally by the PM QoS
framework, causing 0 to be chosen as an effective constraint
value. However, that 0 is then interpreted as "no restriction"
effectively overriding the other requests with specific
restrictions which is incorrect.
Second, the users of device resume latency PM QoS have no
way to specify that *any* resume latency at all should be
avoided, which is an artificial limitation in general.
To address these issues, modify device resume latency PM QoS to
use S32_MAX as the "no constraint" value and 0 as the "no
latency at all" one and rework its users (the cpuidle menu
governor, the genpd QoS governor and the runtime PM framework)
to follow these changes.
Also add a special "n/a" value to the corresponding user space I/F
to allow user space to indicate that it cannot accept any resume
latencies at all for the given device.
Fixes: 85dc0b8a40 (PM / QoS: Make it possible to expose PM QoS latency constraints)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=197323
Reported-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Tero Kristo <t-kristo@ti.com>
Reviewed-by: Ramesh Thomas <ramesh.thomas@intel.com>
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.
For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.
However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:
----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()
// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch
virtual patch
@ depends on patch @
expression E1, E2;
@@
- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)
@ depends on patch @
expression E;
@@
- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. Removes test of .data field, since
that will be going away.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Update the .c files that depend on these APIs.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The might_sleep_if() assertions in __pm_runtime_idle(),
__pm_runtime_suspend() and __pm_runtime_resume() may generate
false-positive warnings in some situations. For example, that
happens if a nested pm_runtime_get_sync()/pm_runtime_put() pair
is executed with disabled interrupts within an outer
pm_runtime_get_sync()/pm_runtime_put() section for the same device.
[Generally, pm_runtime_get_sync() may sleep, so it should not be
called with disabled interrupts, but in this particular case the
previous pm_runtime_get_sync() guarantees that the device will not
be suspended, so the inner pm_runtime_get_sync() will return
immediately after incrementing the device's usage counter.]
That started to happen in the i915 driver in 4.10-rc, leading to
the following splat:
BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:1032
in_atomic(): 1, irqs_disabled(): 0, pid: 1500, name: Xorg
1 lock held by Xorg/1500:
#0: (&dev->struct_mutex){+.+.+.}, at:
[<ffffffffa0680c13>] i915_mutex_lock_interruptible+0x43/0x140 [i915]
CPU: 0 PID: 1500 Comm: Xorg Not tainted
Call Trace:
dump_stack+0x85/0xc2
___might_sleep+0x196/0x260
__might_sleep+0x53/0xb0
__pm_runtime_resume+0x7a/0x90
intel_runtime_pm_get+0x25/0x90 [i915]
aliasing_gtt_bind_vma+0xaa/0xf0 [i915]
i915_vma_bind+0xaf/0x1e0 [i915]
i915_gem_execbuffer_relocate_entry+0x513/0x6f0 [i915]
i915_gem_execbuffer_relocate_vma.isra.34+0x188/0x250 [i915]
? trace_hardirqs_on+0xd/0x10
? i915_gem_execbuffer_reserve_vma.isra.31+0x152/0x1f0 [i915]
? i915_gem_execbuffer_reserve.isra.32+0x372/0x3a0 [i915]
i915_gem_do_execbuffer.isra.38+0xa70/0x1a40 [i915]
? __might_fault+0x4e/0xb0
i915_gem_execbuffer2+0xc5/0x260 [i915]
? __might_fault+0x4e/0xb0
drm_ioctl+0x206/0x450 [drm]
? i915_gem_execbuffer+0x340/0x340 [i915]
? __fget+0x5/0x200
do_vfs_ioctl+0x91/0x6f0
? __fget+0x111/0x200
? __fget+0x5/0x200
SyS_ioctl+0x79/0x90
entry_SYSCALL_64_fastpath+0x23/0xc6
even though the code triggering it is correct.
Unfortunately, the might_sleep_if() assertions in question are
too coarse-grained to cover such cases correctly, so make them
a bit less sensitive in order to avoid the false-positives.
Reported-and-tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Here's the new driver core patches for 4.10-rc1.
Big thing here is the nice addition of "functional dependencies" to the
driver core. The idea has been talked about for a very long time, great
job to Rafael for stepping up and implementing it. It's been tested for
longer than the 4.9-rc1 date, we held off on merging it earlier in order
to feel more comfortable about it.
Other than that, it's just a handful of small other patches, some good
cleanups to the mess that is the firmware class code, and we have a test
driver for the deferred probe logic.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here's the new driver core patches for 4.10-rc1.
Big thing here is the nice addition of "functional dependencies" to
the driver core. The idea has been talked about for a very long time,
great job to Rafael for stepping up and implementing it. It's been
tested for longer than the 4.9-rc1 date, we held off on merging it
earlier in order to feel more comfortable about it.
Other than that, it's just a handful of small other patches, some good
cleanups to the mess that is the firmware class code, and we have a
test driver for the deferred probe logic.
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (30 commits)
firmware: Correct handling of fw_state_wait() return value
driver core: Silence device links sphinx warning
firmware: remove warning at documentation generation time
drivers: base: dma-mapping: Fix typo in dmam_alloc_non_coherent comments
driver core: test_async: fix up typo found by 0-day
firmware: move fw_state_is_done() into UHM section
firmware: do not use fw_lock for fw_state protection
firmware: drop bit ops in favor of simple state machine
firmware: refactor loading status
firmware: fix usermode helper fallback loading
driver core: firmware_class: convert to use class_groups
driver core: devcoredump: convert to use class_groups
driver core: class: add class_groups support
kernfs: Declare two local data structures static
driver-core: fix platform_no_drv_owner.cocci warnings
drivers/base/memory.c: Remove unused 'first_page' variable
driver core: add CLASS_ATTR_WO()
drivers: base: cacheinfo: support DT overrides for cache properties
drivers: base: cacheinfo: add pr_fmt logging
drivers: base: cacheinfo: fix boot error message when acpi is enabled
...
I noticed some wakeirq flakeyness with consumer drivers not using
autosuspend. For drivers not using autosuspend, the wakeirq may never
get unmasked in rpm_suspend() because of irq desc->depth.
We are configuring dedicated wakeirqs to start with IRQ_NOAUTOEN as we
naturally don't want them running until rpm_suspend() is called.
However, when a consumer driver initially calls pm_runtime_get(), we
now wrongly start with disable_irq_nosync() call on the dedicated
wakeirq that is disabled to start with.
This causes desc->depth to toggle between 1 and 2 instead of the usual
0 and 1. This can prevent enable_irq() from unmasking the wakeirq as
that only happens at desc->depth 1.
This does not necessarily show up with drivers using autosuspend as
there is time for disable_irq_nosync() before rpm_suspend() gets called
after the autosuspend timeout.
Let's fix the issue by adding wirq->status that lazily gets set on
the first rpm_suspend(). We also need PM runtime core private functions
for dev_pm_enable_wake_irq_check() and dev_pm_disable_wake_irq_check()
so we can enable the dedicated wakeirq on the first rpm_suspend().
While at it, let's also fix the comments for dev_pm_enable_wake_irq()
and dev_pm_disable_wake_irq(). Those can still be used by the consumer
drivers as needed because the IRQ core manages the interrupt usecount
for us.
Fixes: 4990d4fe32 (PM / Wakeirq: Add automated device wake IRQ handling)
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When the pm_runtime_force_suspend|resume() helpers were invented, we still
had CONFIG_PM_RUNTIME and CONFIG_PM_SLEEP as separate Kconfig options.
To make sure these helpers worked for all combinations and without
introducing too much of complexity, the device was always resumed in
pm_runtime_force_resume().
More precisely, when CONFIG_PM_SLEEP was set and CONFIG_PM_RUNTIME was
unset, we needed to resume the device as the subsystem/driver couldn't
rely on using runtime PM to do it.
As the CONFIG_PM_RUNTIME option was merged into CONFIG_PM a while ago, it
removed this combination, of using CONFIG_PM_SLEEP without the earlier
CONFIG_PM_RUNTIME.
For this reason we can now rely on the subsystem/driver to use runtime PM
to resume the device, instead of forcing that to be done in all cases. In
other words, let's defer the runtime resume to a later point when it's
actually needed.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When resuming a device in __pm_runtime_set_status(), the prerequisite is
that its parent must already be active, else an error code is returned and
the device's status remains suspended.
When suspending a device there is no similar constraints being validated.
Let's change this to make the behaviour consistent, by not allowing to
suspend a device with an active child, unless it has been explicitly set to
ignore its children.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If the device has no links to suppliers that should be used for
runtime PM (links with DEVICE_LINK_PM_RUNTIME set), there is no
reason to walk the list of suppliers for that device during
runtime suspend and resume.
Add a simple mechanism to detect that case and possibly avoid the
extra unnecessary overhead.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Modify the runtime PM framework to use device links to ensure that
supplier devices will not be suspended if any of their consumer
devices are active.
The idea is to reference count suppliers on the consumer's resume
and drop references to them on its suspend. The information on
whether or not the supplier has been reference counted by the
consumer's (runtime) resume is stored in a new field (rpm_active)
in the link object for each link.
It may be necessary to clean up those references when the
supplier is unbinding and that's why the links whose status is
DEVICE_LINK_SUPPLIER_UNBIND are skipped by the runtime suspend
and resume code.
The above means that if the consumer device is probed in the
runtime-active state, the supplier has to be resumed and reference
counted by device_link_add() so the code works as expected on its
(runtime) suspend. There is a new flag, DEVICE_LINK_RPM_ACTIVE,
to tell device_link_add() about that (in which case the caller
is responsible for making sure that the consumer really will
be runtime-active when runtime PM is enabled for it).
The other new link flag, DEVICE_LINK_PM_RUNTIME, tells the core
whether or not the link should be used for runtime PM at all.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The exported function pm_children_suspended() has only one caller, which is
the runtime PM internal function, rpm_check_suspend_allowed().
Let's clean-up this code, by removing pm_children_suspended() altogether
and instead do the one-liner check directly in rpm_check_suspend_allowed().
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Further testing with false negatives suppressed by commit 293e2421fe
("rcu: Remove superfluous versions of rcu_read_lock_sched_held()")
identified a few more unprotected uses of RCU from the idle loop.
Because RCU actively ignores idle-loop code (for energy-efficiency
reasons, among other things), using RCU from the idle loop can result
in too-short grace periods, in turn resulting in arbitrary misbehavior.
The affected function is rpm_suspend().
The resulting lockdep-RCU splat is as follows:
------------------------------------------------------------------------
Warning from omap3
===============================
[ INFO: suspicious RCU usage. ]
4.6.0-rc5-next-20160426+ #1112 Not tainted
-------------------------------
include/trace/events/rpm.h:63 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 0
RCU used illegally from extended quiescent state!
1 lock held by swapper/0/0:
#0: (&(&dev->power.lock)->rlock){-.-...}, at: [<c052ee24>] __pm_runtime_suspend+0x54/0x84
stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1112
Hardware name: Generic OMAP36xx (Flattened Device Tree)
[<c0110308>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14)
[<c010c3a8>] (show_stack) from [<c047fec8>] (dump_stack+0xb0/0xe4)
[<c047fec8>] (dump_stack) from [<c052d7b4>] (rpm_suspend+0x604/0x7e4)
[<c052d7b4>] (rpm_suspend) from [<c052ee34>] (__pm_runtime_suspend+0x64/0x84)
[<c052ee34>] (__pm_runtime_suspend) from [<c04bf3bc>] (omap2_gpio_prepare_for_idle+0x5c/0x70)
[<c04bf3bc>] (omap2_gpio_prepare_for_idle) from [<c01255e8>] (omap_sram_idle+0x140/0x244)
[<c01255e8>] (omap_sram_idle) from [<c0126b48>] (omap3_enter_idle_bm+0xfc/0x1ec)
[<c0126b48>] (omap3_enter_idle_bm) from [<c0601db8>] (cpuidle_enter_state+0x80/0x3d4)
[<c0601db8>] (cpuidle_enter_state) from [<c0183c74>] (cpu_startup_entry+0x198/0x3a0)
[<c0183c74>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8)
[<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c)
------------------------------------------------------------------------
Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit appends a few _rcuidle suffixes to fix the following
RCU-used-from-idle bug:
> ===============================
> [ INFO: suspicious RCU usage. ]
> 4.6.0-rc5-next-20160426+ #1116 Not tainted
> -------------------------------
> include/trace/events/rpm.h:95 suspicious rcu_dereference_check() usage!
>
> other info that might help us debug this:
>
>
> RCU used illegally from idle CPU!
> rcu_scheduler_active = 1, debug_locks = 0
> RCU used illegally from extended quiescent state!
> 1 lock held by swapper/0/0:
> #0: (&(&dev->power.lock)->rlock){-.-...}, at: [<c052cc2c>] __rpm_callback+0x58/0x60
>
> stack backtrace:
> CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1116
> Hardware name: Generic OMAP36xx (Flattened Device Tree)
> [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14)
> [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4)
> [<c047fd68>] (dump_stack) from [<c052d5d0>] (rpm_suspend+0x580/0x768)
> [<c052d5d0>] (rpm_suspend) from [<c052ec58>] (__pm_runtime_suspend+0x64/0x84)
> [<c052ec58>] (__pm_runtime_suspend) from [<c04bf25c>] (omap2_gpio_prepare_for_idle+0x5c/0x70)
> [<c04bf25c>] (omap2_gpio_prepare_for_idle) from [<c0125568>] (omap_sram_idle+0x140/0x244)
> [<c0125568>] (omap_sram_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec)
> [<c01269dc>] (omap3_enter_idle_bm) from [<c0601bdc>] (cpuidle_enter_state+0x80/0x3d4)
> [<c0601bdc>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0)
> [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8)
> [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c)
In the immortal words of Steven Rostedt, "*Whack* *Whack* *Whack*!!!"
Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
WhACKED-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
