linux-stable.git/drivers/cpuidle, branch v4.0.8 Linux kernel stable tree tick/idle/powerpc: Do not register idle states with CPUIDLE_FLAG_TIMER_STOP set in periodic mode 2015-07-10T16:45:41+00:00 preeti preeti@linux.vnet.ibm.com 2015-06-24T06:48:01+00:00 dddd1a01d6c5eb84bd403ddec87d2e5852426371 commit cc5a2f7b8f39e7db559778f7913a2410257b3e50 upstream. On some archs, the local clockevent device stops in deep cpuidle states. The broadcast framework is used to wakeup cpus in these idle states, in which either an external clockevent device is used to send wakeup ipis or the hrtimer broadcast framework kicks in in the absence of such a device. One cpu is nominated as the broadcast cpu and this cpu sends wakeup ipis to sleeping cpus at the appropriate time. This is the implementation in the oneshot mode of broadcast. In periodic mode of broadcast however, the presence of such cpuidle states results in the cpuidle driver calling tick_broadcast_enable() which shuts down the local clockevent devices of all the cpus and appoints the tick broadcast device as the clockevent device for each of them. This works on those archs where the tick broadcast device is a real clockevent device. But on archs which depend on the hrtimer mode of broadcast, the tick broadcast device hapens to be a pseudo device. The consequence is that the local clockevent devices of all cpus are shutdown and the kernel hangs at boot time in periodic mode. Let us thus not register the cpuidle states which have CPUIDLE_FLAG_TIMER_STOP flag set, on archs which depend on the hrtimer mode of broadcast in periodic mode. This patch takes care of doing this on powerpc. The cpus would not have entered into such deep cpuidle states in periodic mode on powerpc anyway. So there is no loss here. Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit cc5a2f7b8f39e7db559778f7913a2410257b3e50 upstream.

On some archs, the local clockevent device stops in deep cpuidle states.
The broadcast framework is used to wakeup cpus in these idle states, in
which either an external clockevent device is used to send wakeup ipis
or the hrtimer broadcast framework kicks in in the absence of such a
device. One cpu is nominated as the broadcast cpu and this cpu sends
wakeup ipis to sleeping cpus at the appropriate time. This is the
implementation in the oneshot mode of broadcast.

In periodic mode of broadcast however, the presence of such cpuidle
states results in the cpuidle driver calling tick_broadcast_enable()
which shuts down the local clockevent devices of all the cpus and
appoints the tick broadcast device as the clockevent device for each of
them. This works on those archs where the tick broadcast device is a
real clockevent device.  But on archs which depend on the hrtimer mode
of broadcast, the tick broadcast device hapens to be a pseudo device.
The consequence is that the local clockevent devices of all cpus are
shutdown and the kernel hangs at boot time in periodic mode.

Let us thus not register the cpuidle states which have
CPUIDLE_FLAG_TIMER_STOP flag set, on archs which depend on the hrtimer
mode of broadcast in periodic mode. This patch takes care of doing this
on powerpc. The cpus would not have entered into such deep cpuidle
states in periodic mode on powerpc anyway. So there is no loss here.

Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpuidle: remove state_count field from struct cpuidle_device 2015-04-03T11:15:50+00:00 Bartlomiej Zolnierkiewicz b.zolnierkie@samsung.com 2015-03-31T18:15:09+00:00 d75e4af14e228bbe3f86e29bcecb8e6be98d4e04 Thomas Schlichter reports the following issue on his Samsung NC20: "The C-states C1 and C2 to the OS when connected to AC, and additionally provides the C3 C-state when disconnected from AC. However, the number of C-states shown in sysfs is fixed to the number of C-states present at boot. If I boot with AC connected, I always only see the C-states up to C2 even if I disconnect AC. The reason is commit 130a5f692425 (ACPI / cpuidle: remove dev->state_count setting). It removes the update of dev->state_count, but sysfs uses exactly this variable to show the C-states. The fix is to use drv->state_count in sysfs. As this is currently the last user of dev->state_count, this variable can be completely removed." Remove dev->state_count as per the above. Reported-by: Thomas Schlichter <thomas.schlichter@web.de> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: 3.14+ <stable@vger.kernel.org> # 3.14+ [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Thomas Schlichter reports the following issue on his Samsung NC20:

"The C-states C1 and C2 to the OS when connected to AC, and additionally
 provides the C3 C-state when disconnected from AC.  However, the number
 of C-states shown in sysfs is fixed to the number of C-states present
 at boot.
   If I boot with AC connected, I always only see the C-states up to C2
   even if I disconnect AC.

   The reason is commit 130a5f692425 (ACPI / cpuidle: remove dev->state_count
   setting).  It removes the update of dev->state_count, but sysfs uses
   exactly this variable to show the C-states.

   The fix is to use drv->state_count in sysfs.  As this is currently the
   last user of dev->state_count, this variable can be completely removed."

Remove dev->state_count as per the above.

Reported-by: Thomas Schlichter <thomas.schlichter@web.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpuidle: mvebu: Update cpuidle thresholds for Armada XP SOCs 2015-03-13T17:31:29+00:00 Sebastien Rannou mxs@sbrk.org 2015-02-13T14:55:03+00:00 ce6031c89a35cffd5a5992b08377b77f49a004b9 Originally, the thresholds used in the cpuidle driver for Armada SOCs were temporarily chosen, leaving room for improvements. This commit updates the thresholds for the Armada XP SOCs with values that positively impact performances: without patch with patch vendor kernel - iperf localhost (gbit/sec) ~3.7 ~6.4 ~5.4 - ioping tmpfs (iops) ~163k ~206k ~179k - ioping tmpfs (mib/s) ~636 ~805 ~699 The idle power consumption is negatively impacted (proportionally less than the performance gain), and we are still performing better than the vendor kernel here: without patch with patch vendor kernel - power consumption idle (W) ~2.4 ~3.2 ~4.4 - power consumption busy (W) ~8.6 ~8.3 ~8.6 There is still room for improvement regarding the value of these thresholds, they were chosen to mimic the vendor kernel. This patch only impacts Armada XP SOCs and was tested on Online Labs C1 boards. A similar approach can be taken to improve the performances of the Armada 370 and Armada 38x SOCs. Thanks a lot to Thomas Petazzoni, Gregory Clement and Willy Tarreau for the discussions and tips around this topic. Signed-off-by: Sebastien Rannou <mxs@sbrk.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com> 
Originally, the thresholds used in the cpuidle driver for Armada SOCs
were temporarily chosen, leaving room for improvements.

This commit updates the thresholds for the Armada XP SOCs with values
that positively impact performances:

                                without patch  with patch   vendor kernel
 - iperf localhost (gbit/sec)   ~3.7           ~6.4         ~5.4
 - ioping tmpfs (iops)          ~163k          ~206k        ~179k
 - ioping tmpfs (mib/s)         ~636           ~805         ~699

The idle power consumption is negatively impacted (proportionally less
than the performance gain), and we are still performing better than
the vendor kernel here:

                                without patch   with patch  vendor kernel
 - power consumption idle (W)   ~2.4            ~3.2        ~4.4
 - power consumption busy (W)   ~8.6            ~8.3        ~8.6

There is still room for improvement regarding the value of these
thresholds, they were chosen to mimic the vendor kernel.

This patch only impacts Armada XP SOCs and was tested on Online Labs
C1 boards. A similar approach can be taken to improve the performances
of the Armada 370 and Armada 38x SOCs.

Thanks a lot to Thomas Petazzoni, Gregory Clement and Willy Tarreau
for the discussions and tips around this topic.

Signed-off-by: Sebastien Rannou <mxs@sbrk.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
cpuidle: mvebu: Fix the CPU PM notifier usage 2015-03-13T17:26:06+00:00 Gregory CLEMENT gregory.clement@free-electrons.com 2015-02-26T17:20:48+00:00 43b68879de27b1993518687fbc6013da80cdcbfe As stated in kernel/cpu_pm.c, "Platform is responsible for ensuring that cpu_pm_enter is not called twice on the same CPU before cpu_pm_exit is called.". In the current code in case of failure when calling mvebu_v7_cpu_suspend, the function cpu_pm_exit() is never called whereas cpu_pm_enter() was called just before. This patch moves the cpu_pm_exit() in order to balance the cpu_pm_enter() calls. Cc: stable@vger.kernel.org Reported-by: Fulvio Benini <fbf@libero.it> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> 
As stated in kernel/cpu_pm.c, "Platform is responsible for ensuring
that cpu_pm_enter is not called twice on the same CPU before
cpu_pm_exit is called.". In the current code in case of failure when
calling mvebu_v7_cpu_suspend, the function cpu_pm_exit() is never
called whereas cpu_pm_enter() was called just before.

This patch moves the cpu_pm_exit() in order to balance the
cpu_pm_enter() calls.

Cc: stable@vger.kernel.org
Reported-by: Fulvio Benini <fbf@libero.it>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
cpuidle / sleep: Use broadcast timer for states that stop local timer 2015-03-05T22:13:19+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2015-03-02T21:26:55+00:00 ef2b22ac540c018bd574d1846ab95b9bfcf38702 Commit 381063133246 (PM / sleep: Re-implement suspend-to-idle handling) overlooked the fact that entering some sufficiently deep idle states by CPUs may cause their local timers to stop and in those cases it is necessary to switch over to a broadcast timer prior to entering the idle state. If the cpuidle driver in use does not provide the new ->enter_freeze callback for any of the idle states, that problem affects suspend-to-idle too, but it is not taken into account after the changes made by commit 381063133246. Fix that by changing the definition of cpuidle_enter_freeze() and re-arranging of the code in cpuidle_idle_call(), so the former does not call cpuidle_enter() any more and the fallback case is handled by cpuidle_idle_call() directly. Fixes: 381063133246 (PM / sleep: Re-implement suspend-to-idle handling) Reported-and-tested-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> 
Commit 381063133246 (PM / sleep: Re-implement suspend-to-idle handling)
overlooked the fact that entering some sufficiently deep idle states
by CPUs may cause their local timers to stop and in those cases it
is necessary to switch over to a broadcast timer prior to entering
the idle state.  If the cpuidle driver in use does not provide
the new ->enter_freeze callback for any of the idle states, that
problem affects suspend-to-idle too, but it is not taken into account
after the changes made by commit 381063133246.

Fix that by changing the definition of cpuidle_enter_freeze() and
re-arranging of the code in cpuidle_idle_call(), so the former does
not call cpuidle_enter() any more and the fallback case is handled
by cpuidle_idle_call() directly.

Fixes: 381063133246 (PM / sleep: Re-implement suspend-to-idle handling)
Reported-and-tested-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
cpuidle / sleep: Do sanity checks in cpuidle_enter_freeze() too 2015-02-28T22:46:39+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2015-02-26T23:39:56+00:00 31a3409065d1d5bf0f12ad76b8c7f471134bf596 Modify cpuidle_enter_freeze() to do the sanity checks done by cpuidle_select() to avoid crashing the suspend-to-idle code path in case something is missing. Fixes: 381063133246 (PM / sleep: Re-implement suspend-to-idle handling) Original-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> 
Modify cpuidle_enter_freeze() to do the sanity checks done by
cpuidle_select() to avoid crashing the suspend-to-idle code
path in case something is missing.

Fixes: 381063133246 (PM / sleep: Re-implement suspend-to-idle handling)
Original-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
idle / sleep: Avoid excessive disabling and enabling interrupts 2015-02-28T22:46:24+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2015-02-26T23:39:21+00:00 01e04f466e12e883907937eb04a9010533363f55 Disabling interrupts at the end of cpuidle_enter_freeze() is not useful, because its caller, cpuidle_idle_call(), re-enables them right away after invoking it. To avoid that unnecessary back and forth dance with interrupts, make cpuidle_enter_freeze() enable interrupts after calling enter_freeze_proper() and drop the local_irq_disable() at its end, so that all of the code paths in it end up with interrupts enabled. Then, cpuidle_idle_call() will not need to re-enable interrupts after calling cpuidle_enter_freeze() any more, because the latter will return with interrupts enabled, in analogy with cpuidle_enter(). Reported-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> 
Disabling interrupts at the end of cpuidle_enter_freeze() is not
useful, because its caller, cpuidle_idle_call(), re-enables them
right away after invoking it.

To avoid that unnecessary back and forth dance with interrupts,
make cpuidle_enter_freeze() enable interrupts after calling
enter_freeze_proper() and drop the local_irq_disable() at its
end, so that all of the code paths in it end up with interrupts
enabled.  Then, cpuidle_idle_call() will not need to re-enable
interrupts after calling cpuidle_enter_freeze() any more, because
the latter will return with interrupts enabled, in analogy with
cpuidle_enter().

Reported-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Merge branches 'pnp', 'pm-cpuidle' and 'pm-cpufreq' 2015-02-21T03:29:16+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2015-02-21T03:29:16+00:00 3466b547e37b988723dc93465b7cb06b4b1f731f * pnp: PNP: Switch from __check_region() to __request_region() * pm-cpuidle: cpuidle: powernv: Avoid endianness conversions while parsing DT cpuidle: powernv: Read target_residency value of idle states from DT if available * pm-cpufreq: cpufreq: s3c: remove last use of resume_clocks callback cpufreq: s3c: remove incorrect __init annotations 
* pnp:
  PNP: Switch from __check_region() to __request_region()

* pm-cpuidle:
  cpuidle: powernv: Avoid endianness conversions while parsing DT
  cpuidle: powernv: Read target_residency value of idle states from DT if available

* pm-cpufreq:
  cpufreq: s3c: remove last use of resume_clocks callback
  cpufreq: s3c: remove incorrect __init annotations
cpuidle: powernv: Avoid endianness conversions while parsing DT 2015-02-19T22:44:38+00:00 Preeti U Murthy preeti@linux.vnet.ibm.com 2015-02-19T05:24:53+00:00 70734a786acfd1998e47d40df19cba5c29469bdf We currently read the information about idle states from the DT so as to populate the cpuidle table. Use those APIs to read from the DT that can avoid endianness conversions of the property values in the cpuidle driver. Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
We currently read the information about idle states from the DT
so as to populate the cpuidle table. Use those APIs to read from
the DT that can avoid endianness conversions of the property values
in the cpuidle driver.

Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpuidle: powernv: Read target_residency value of idle states from DT if available 2015-02-18T05:34:17+00:00 Preeti U Murthy preeti@linux.vnet.ibm.com 2015-02-18T05:34:17+00:00 92c83ff5b42b109c94fdeee53cb31f674f776d75 The device tree now exposes the residency values for different idle states. Read these values instead of calculating residency from the latency values. The values exposed in the DT are validated for optimal power efficiency. However to maintain compatibility with the older firmware code which does not expose residency values, use default values as a fallback mechanism. While at it, use better APIs to parse the powermgmt device tree node. Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Acked-by: Stewart Smith <stewart@linux.vnet.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
The device tree now exposes the residency values for different idle states. Read
these values instead of calculating residency from the latency values. The values
exposed in the DT are validated for optimal power efficiency. However to maintain
compatibility with the older firmware code which does not expose residency
values, use default values as a fallback mechanism. While at it, use better
APIs to parse the powermgmt device tree node.

Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>