- 03 4月, 2015 3 次提交
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由 Thomas Gleixner 提交于
clockevents_notify() is a leftover from the early design of the clockevents facility. It's really not a notification mechanism, it's a multiplex call. We are way better off to have explicit calls instead of this monstrosity. Split out the cleanup function for a dead cpu and invoke it directly from the cpu down code. Make it conditional on CPU_HOTPLUG as well. Temporary change, will be refined in the future. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> [ Rebased, added clockevents_notify() removal ] Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1735025.raBZdQHM3m@vostro.rjw.lanSigned-off-by: NIngo Molnar <mingo@kernel.org>
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由 Thomas Gleixner 提交于
clockevents_notify() is a leftover from the early design of the clockevents facility. It's really not a notification mechanism, it's a multiplex call. We are way better off to have explicit calls instead of this monstrosity. Split out the broadcast oneshot control into a separate function and provide inline helpers. Switch clockevents_notify() over. This will go away once all callers are converted. This also gets rid of the nested locking of clockevents_lock and broadcast_lock. The broadcast oneshot control functions do not require clockevents_lock. Only the managing functions (setup/shutdown/suspend/resume of the broadcast device require clockevents_lock. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Alexandre Courbot <gnurou@gmail.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Len Brown <lenb@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Warren <swarren@wwwdotorg.org> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Tony Lindgren <tony@atomide.com> Link: http://lkml.kernel.org/r/13000649.8qZuEDV0OA@vostro.rjw.lanSigned-off-by: NIngo Molnar <mingo@kernel.org>
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由 Thomas Gleixner 提交于
clockevents_notify() is a leftover from the early design of the clockevents facility. It's really not a notification mechanism, it's a multiplex call. We are way better off to have explicit calls instead of this monstrosity. Split out the broadcast control into a separate function and provide inline helpers. Switch clockevents_notify() over. This will go away once all callers are converted. This also gets rid of the nested locking of clockevents_lock and broadcast_lock. The broadcast control functions do not require clockevents_lock. Only the managing functions (setup/shutdown/suspend/resume of the broadcast device require clockevents_lock. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Len Brown <lenb@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tony Lindgren <tony@atomide.com> Link: http://lkml.kernel.org/r/8086559.ttsuS0n1Xr@vostro.rjw.lanSigned-off-by: NIngo Molnar <mingo@kernel.org>
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- 02 4月, 2015 1 次提交
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由 Preeti U Murthy 提交于
It was found when doing a hotplug stress test on POWER, that the machine either hit softlockups or rcu_sched stall warnings. The issue was traced to commit: 7cba160a ("powernv/cpuidle: Redesign idle states management") which exposed the cpu_down() race with hrtimer based broadcast mode: 5d1638ac ("tick: Introduce hrtimer based broadcast") The race is the following: Assume CPU1 is the CPU which holds the hrtimer broadcasting duty before it is taken down. CPU0 CPU1 cpu_down() take_cpu_down() disable_interrupts() cpu_die() while (CPU1 != CPU_DEAD) { msleep(100); switch_to_idle(); stop_cpu_timer(); schedule_broadcast(); } tick_cleanup_cpu_dead() take_over_broadcast() So after CPU1 disabled interrupts it cannot handle the broadcast hrtimer anymore, so CPU0 will be stuck forever. Fix this by explicitly taking over broadcast duty before cpu_die(). This is a temporary workaround. What we really want is a callback in the clockevent device which allows us to do that from the dying CPU by pushing the hrtimer onto a different cpu. That might involve an IPI and is definitely more complex than this immediate fix. Changelog was picked up from: https://lkml.org/lkml/2015/2/16/213Suggested-by: NThomas Gleixner <tglx@linutronix.de> Tested-by: NNicolas Pitre <nico@linaro.org> Signed-off-by: NPreeti U. Murthy <preeti@linux.vnet.ibm.com> Cc: linuxppc-dev@lists.ozlabs.org Cc: mpe@ellerman.id.au Cc: nicolas.pitre@linaro.org Cc: peterz@infradead.org Cc: rjw@rjwysocki.net Fixes: http://linuxppc.10917.n7.nabble.com/offlining-cpus-breakage-td88619.html Link: http://lkml.kernel.org/r/20150330092410.24979.59887.stgit@preeti.in.ibm.com [ Merged it to the latest timer tree, renamed the callback, tidied up the changelog. ] Signed-off-by: NIngo Molnar <mingo@kernel.org>
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- 01 4月, 2015 2 次提交
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由 Thomas Gleixner 提交于
Xen calls on every cpu into tick_resume() which is just wrong. tick_resume() is for the syscore global suspend/resume invocation. What XEN really wants is a per cpu local resume function. Provide a tick_resume_local() function and use it in XEN. Also provide a complementary tick_suspend_local() and modify tick_unfreeze() and tick_freeze(), respectively, to use the new local tick resume/suspend functions. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> [ Combined two patches, rebased, modified subject/changelog. ] Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1698741.eezk9tnXtG@vostro.rjw.lan [ Merged to latest timers/core. ] Signed-off-by: NIngo Molnar <mingo@kernel.org>
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由 Thomas Gleixner 提交于
Solely used in tick-broadcast.c and the return value is hardcoded 0. Make it static and void. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1689058.QkHYDJSRKu@vostro.rjw.lanSigned-off-by: NIngo Molnar <mingo@kernel.org>
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- 27 3月, 2015 2 次提交
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由 Viresh Kumar 提交于
'enum clock_event_mode' is used for two purposes today: - to pass mode to the driver of clockevent device::set_mode(). - for managing state of the device for clockevents core. For supporting new modes/states we have moved away from the legacy set_mode() callback to new per-mode/state callbacks. New modes/states shouldn't be exposed to the legacy (now OBSOLOTE) callbacks and so we shouldn't add new states to 'enum clock_event_mode'. Lets have separate enums for the two use cases mentioned above. Keep using the earlier enum for legacy set_mode() callback and mark it OBSOLETE. And add another enum to clearly specify the possible states of a clockevent device. This also renames the newly added per-mode callbacks to reflect state changes. We haven't got rid of 'mode' member of 'struct clock_event_device' as it is used by some of the clockevent drivers and it would automatically die down once we migrate those drivers to the new interface. It ('mode') is only updated now for the drivers using the legacy interface. Suggested-by: NPeter Zijlstra <peterz@infradead.org> Suggested-by: NIngo Molnar <mingo@kernel.org> Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org> Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Kevin Hilman <khilman@linaro.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: linaro-kernel@lists.linaro.org Cc: linaro-networking@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/b6b0143a8a57bd58352ad35e08c25424c879c0cb.1425037853.git.viresh.kumar@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
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由 Viresh Kumar 提交于
Upcoming patch will redefine possible states of a clockevent device. The RESUME mode is a special case only for tick's clockevent devices. In future it can be replaced by ->resume() callback already available for clockevent devices. Lets handle it separately so that clockevents_set_mode() only handles states valid across all devices. This also renames set_mode_resume() to tick_resume() to make it more explicit. Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org> Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Kevin Hilman <khilman@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: linaro-kernel@lists.linaro.org Cc: linaro-networking@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/c1b0112410870f49e7bf06958e1483eac6c15e20.1425037853.git.viresh.kumar@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
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- 27 8月, 2014 1 次提交
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由 Christoph Lameter 提交于
Convert uses of __get_cpu_var for creating a address from a percpu offset to this_cpu_ptr. The two cases where get_cpu_var is used to actually access a percpu variable are changed to use this_cpu_read/raw_cpu_read. Reviewed-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NChristoph Lameter <cl@linux.com> Signed-off-by: NTejun Heo <tj@kernel.org>
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- 14 2月, 2014 1 次提交
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由 Thomas Gleixner 提交于
AMD systems which use the C1E workaround in the amd_e400_idle routine trigger the WARN_ON_ONCE in the broadcast code when onlining a CPU. The reason is that the idle routine of those AMD systems switches the cpu into forced broadcast mode early on before the newly brought up CPU can switch over to high resolution / NOHZ mode. The timer related CPU1 bringup looks like this: clockevent_register_device(local_apic); tick_setup(local_apic); ... idle() tick_broadcast_on_off(FORCE); tick_broadcast_oneshot_control(ENTER) cpumask_set(cpu, broadcast_oneshot_mask); halt(); Now the broadcast interrupt on CPU0 sets CPU1 in the broadcast_pending_mask and wakes CPU1. So CPU1 continues: local_apic_timer_interrupt() tick_handle_periodic(); softirq() tick_init_highres(); cpumask_clr(cpu, broadcast_oneshot_mask); tick_broadcast_oneshot_control(ENTER) WARN_ON(cpumask_test(cpu, broadcast_pending_mask); So while we remove CPU1 from the broadcast_oneshot_mask when we switch over to highres mode, we do not clear the pending bit, which then triggers the warning when we go back to idle. The reason why this is only visible on C1E affected AMD systems is that the other machines enter the deep sleep states via acpi_idle/intel_idle and exit the broadcast mode before executing the remote triggered local_apic_timer_interrupt. So the pending bit is already cleared when the switch over to highres mode is clearing the oneshot mask. The solution is simple: Clear the pending bit together with the mask bit when we switch over to highres mode. Stanislaw came up independently with the same patch by enforcing the C1E workaround and debugging the fallout. I picked mine, because mine has a changelog :) Reported-by: Npoma <pomidorabelisima@gmail.com> Debugged-by: NStanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: Olaf Hering <olaf@aepfle.de> Cc: Dave Jones <davej@redhat.com> Cc: Justin M. Forbes <jforbes@redhat.com> Cc: Josh Boyer <jwboyer@redhat.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1402111434180.21991@ionos.tec.linutronix.de Cc: stable@vger.kernel.org # 3.10+ Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 07 2月, 2014 3 次提交
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由 Preeti U Murthy 提交于
On some architectures, in certain CPU deep idle states the local timers stop. An external clock device is used to wakeup these CPUs. The kernel support for the wakeup of these CPUs is provided by the tick broadcast framework by using the external clock device as the wakeup source. However not all implementations of architectures provide such an external clock device. This patch includes support in the broadcast framework to handle the wakeup of the CPUs in deep idle states on such systems by queuing a hrtimer on one of the CPUs, which is meant to handle the wakeup of CPUs in deep idle states. This patchset introduces a pseudo clock device which can be registered by the archs as tick_broadcast_device in the absence of a real external clock device. Once registered, the broadcast framework will work as is for these architectures as long as the archs take care of the BROADCAST_ENTER notification failing for one of the CPUs. This CPU is made the stand by CPU to handle wakeup of the CPUs in deep idle and it *must not enter deep idle states*. The CPU with the earliest wakeup is chosen to be this CPU. Hence this way the stand by CPU dynamically moves around and so does the hrtimer which is queued to trigger at the next earliest wakeup time. This is consistent with the case where an external clock device is present. The smp affinity of this clock device is set to the CPU with the earliest wakeup. This patchset handles the hotplug of the stand by CPU as well by moving the hrtimer on to the CPU handling the CPU_DEAD notification. Originally-from: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NPreeti U Murthy <preeti@linux.vnet.ibm.com> Cc: deepthi@linux.vnet.ibm.com Cc: paulmck@linux.vnet.ibm.com Cc: fweisbec@gmail.com Cc: paulus@samba.org Cc: srivatsa.bhat@linux.vnet.ibm.com Cc: svaidy@linux.vnet.ibm.com Cc: peterz@infradead.org Cc: benh@kernel.crashing.org Cc: rafael.j.wysocki@intel.com Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/20140207080632.17187.80532.stgit@preeti.in.ibm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Preeti U Murthy 提交于
The broadcast framework can potentially be made use of by archs which do not have an external clock device as well. Then, it is required that one of the CPUs need to handle the broadcasting of wakeup IPIs to the CPUs in deep idle. As a result its local timers should remain functional all the time. For such a CPU, the BROADCAST_ENTER notification has to fail indicating that its clock device cannot be shutdown. To make way for this support, change the return type of tick_broadcast_oneshot_control() and hence clockevents_notify() to indicate such scenarios. Signed-off-by: NPreeti U Murthy <preeti@linux.vnet.ibm.com> Cc: deepthi@linux.vnet.ibm.com Cc: paulmck@linux.vnet.ibm.com Cc: fweisbec@gmail.com Cc: paulus@samba.org Cc: srivatsa.bhat@linux.vnet.ibm.com Cc: svaidy@linux.vnet.ibm.com Cc: peterz@infradead.org Cc: benh@kernel.crashing.org Cc: rafael.j.wysocki@intel.com Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/20140207080606.17187.78306.stgit@preeti.in.ibm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Thomas Gleixner 提交于
We can identify the broadcast device in the core and serialize all callers including interrupts on a different CPU against the update. Also, disabling interrupts is moved into the core allowing callers to leave interrutps enabled when calling clockevents_update_freq(). Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Soeren Brinkmann <soren.brinkmann@xilinx.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Michal Simek <michal.simek@xilinx.com> Link: http://lkml.kernel.org/r/1391466877-28908-2-git-send-email-soren.brinkmann@xilinx.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 03 12月, 2013 1 次提交
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由 Frederic Weisbecker 提交于
A few functions use remote per CPU access APIs when they deal with local values. Just do the right conversion to improve performance, code readability and debug checks. While at it, lets extend some of these function names with *_this_cpu() suffix in order to display their purpose more clearly. Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org>
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- 02 10月, 2013 1 次提交
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由 Soren Brinkmann 提交于
On most ARM systems the per-cpu clockevents are truly per-cpu in the sense that they can't be controlled on any other CPU besides the CPU that they interrupt. If one of these clockevents were to become a broadcast source we will run into a lot of trouble because the broadcast source is enabled on the first CPU to go into deep idle (if that CPU suffers from FEAT_C3_STOP) and that could be a different CPU than what the clockevent is interrupting (or even worse the CPU that the clockevent interrupts could be offline). Theoretically it's possible to support per-cpu clockevents as the broadcast source but so far we haven't needed this and supporting it is rather complicated. Let's just deny the possibility for now until this becomes a reality (let's hope it never does!). Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Acked-by: NMichal Simek <michal.simek@xilinx.com>
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- 12 7月, 2013 1 次提交
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由 Stephen Boyd 提交于
On ARM systems the dummy clockevent is registered with the cpu hotplug notifier chain before any other per-cpu clockevent. This has the side-effect of causing the dummy clockevent to be registered first in every hotplug sequence. Because the dummy is first, we'll try to turn the broadcast source on but the code in tick_device_uses_broadcast() assumes the broadcast source is in periodic mode and calls tick_broadcast_start_periodic() unconditionally. On boot this isn't a problem because we typically haven't switched into oneshot mode yet (if at all). During hotplug, if the broadcast source isn't in periodic mode we'll replace the broadcast oneshot handler with the broadcast periodic handler and start emulating oneshot mode when we shouldn't. Due to the way the broadcast oneshot handler programs the next_event it's possible for it to contain KTIME_MAX and cause us to hang the system when the periodic handler tries to program the next tick. Fix this by using the appropriate function to start the broadcast source. Reported-by: NStephen Warren <swarren@nvidia.com> Tested-by: NStephen Warren <swarren@nvidia.com> Signed-off-by: NStephen Boyd <sboyd@codeaurora.org> Cc: Mark Rutland <Mark.Rutland@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: ARM kernel mailing list <linux-arm-kernel@lists.infradead.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Joseph Lo <josephl@nvidia.com> Link: http://lkml.kernel.org/r/20130711140059.GA27430@codeaurora.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 02 7月, 2013 3 次提交
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由 Thomas Gleixner 提交于
The recent implementation of a generic dummy timer resulted in a different registration order of per cpu local timers which made the broadcast control logic go belly up. If the dummy timer is the first clock event device which is registered for a CPU, then it is installed, the broadcast timer is initialized and the CPU is marked as broadcast target. If a real clock event device is installed after that, we can fail to take the CPU out of the broadcast mask. In the worst case we end up with two periodic timer events firing for the same CPU. One from the per cpu hardware device and one from the broadcast. Now the problem is that we have no way to distinguish whether the system is in a state which makes broadcasting necessary or the broadcast bit was set due to the nonfunctional dummy timer installment. To solve this we need to keep track of the system state seperately and provide a more detailed decision logic whether we keep the CPU in broadcast mode or not. The old decision logic only clears the broadcast mode, if the newly installed clock event device is not affected by power states. The new logic clears the broadcast mode if one of the following is true: - The new device is not affected by power states. - The system is not in a power state affected mode - The system has switched to oneshot mode. The oneshot broadcast is controlled from the deep idle state. The CPU is not in idle at this point, so it's safe to remove it from the mask. If we clear the broadcast bit for the CPU when a new device is installed, we also shutdown the broadcast device when this was the last CPU in the broadcast mask. If the broadcast bit is kept, then we leave the new device in shutdown state and rely on the broadcast to deliver the timer interrupts via the broadcast ipis. Reported-and-tested-by: NStehle Vincent-B46079 <B46079@freescale.com> Reviewed-by: NStephen Boyd <sboyd@codeaurora.org> Cc: John Stultz <john.stultz@linaro.org>, Cc: Mark Rutland <mark.rutland@arm.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1307012153060.4013@ionos.tec.linutronix.de Cc: stable@vger.kernel.org Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Thomas Gleixner 提交于
When the system switches from periodic to oneshot mode, the broadcast logic causes a possibility that a CPU which has not yet switched to oneshot mode puts its own clock event device into oneshot mode without updating the state and the timer handler. CPU0 CPU1 per cpu tickdev is in periodic mode and switched to broadcast Switch to oneshot mode tick_broadcast_switch_to_oneshot() cpumask_copy(tick_oneshot_broacast_mask, tick_broadcast_mask); broadcast device mode = oneshot Timer interrupt irq_enter() tick_check_oneshot_broadcast() dev->set_mode(ONESHOT); tick_handle_periodic() if (dev->mode == ONESHOT) dev->next_event += period; FAIL. We fail, because dev->next_event contains KTIME_MAX, if the device was in periodic mode before the uncontrolled switch to oneshot happened. We must copy the broadcast bits over to the oneshot mask, because otherwise a CPU which relies on the broadcast would not been woken up anymore after the broadcast device switched to oneshot mode. So we need to verify in tick_check_oneshot_broadcast() whether the CPU has already switched to oneshot mode. If not, leave the device untouched and let the CPU switch controlled into oneshot mode. This is a long standing bug, which was never noticed, because the main user of the broadcast x86 cannot run into that scenario, AFAICT. The nonarchitected timer mess of ARM creates a gazillion of differently broken abominations which trigger the shortcomings of that broadcast code, which better had never been necessary in the first place. Reported-and-tested-by: NStehle Vincent-B46079 <B46079@freescale.com> Reviewed-by: NStephen Boyd <sboyd@codeaurora.org> Cc: John Stultz <john.stultz@linaro.org>, Cc: Mark Rutland <mark.rutland@arm.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1307012153060.4013@ionos.tec.linutronix.de Cc: stable@vger.kernel.org Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Thomas Gleixner 提交于
In periodic mode we remove offline cpus from the broadcast propagation mask. In oneshot mode we fail to do so. This was not a problem so far, but the recent changes to the broadcast propagation introduced a constellation which can result in a NULL pointer dereference. What happens is: CPU0 CPU1 idle() arch_idle() tick_broadcast_oneshot_control(OFF); set cpu1 in tick_broadcast_force_mask if (cpu_offline()) arch_cpu_dead() cpu_dead_cleanup(cpu1) cpu1 tickdevice pointer = NULL broadcast interrupt dereference cpu1 tickdevice pointer -> OOPS We dereference the pointer because cpu1 is still set in tick_broadcast_force_mask and tick_do_broadcast() expects a valid cpumask and therefor lacks any further checks. Remove the cpu from the tick_broadcast_force_mask before we set the tick device pointer to NULL. Also add a sanity check to the oneshot broadcast function, so we can detect such issues w/o crashing the machine. Reported-by: NPrarit Bhargava <prarit@redhat.com> Cc: athorlton@sgi.com Cc: CAI Qian <caiqian@redhat.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1306261303260.4013@ionos.tec.linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 21 6月, 2013 1 次提交
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由 Daniel Lezcano 提交于
The recent modification in the cpuidle framework consolidated the timer broadcast code across the different drivers by setting a new flag in the idle state. It tells the cpuidle core code to enter/exit the broadcast mode for the cpu when entering a deep idle state. The broadcast timer enter/exit is no longer handled by the back-end driver. This change made the local interrupt to be enabled *before* calling CLOCK_EVENT_NOTIFY_EXIT. On a tegra114, a four cores system, when the flag has been introduced in the driver, the following warning appeared: WARNING: at kernel/time/tick-broadcast.c:578 tick_broadcast_oneshot_control CPU: 2 PID: 0 Comm: swapper/2 Not tainted 3.10.0-rc3-next-20130529+ #15 [<c00667f8>] (tick_broadcast_oneshot_control+0x1a4/0x1d0) from [<c0065cd0>] (tick_notify+0x240/0x40c) [<c0065cd0>] (tick_notify+0x240/0x40c) from [<c0044724>] (notifier_call_chain+0x44/0x84) [<c0044724>] (notifier_call_chain+0x44/0x84) from [<c0044828>] (raw_notifier_call_chain+0x18/0x20) [<c0044828>] (raw_notifier_call_chain+0x18/0x20) from [<c00650cc>] (clockevents_notify+0x28/0x170) [<c00650cc>] (clockevents_notify+0x28/0x170) from [<c033f1f0>] (cpuidle_idle_call+0x11c/0x168) [<c033f1f0>] (cpuidle_idle_call+0x11c/0x168) from [<c000ea94>] (arch_cpu_idle+0x8/0x38) [<c000ea94>] (arch_cpu_idle+0x8/0x38) from [<c005ea80>] (cpu_startup_entry+0x60/0x134) [<c005ea80>] (cpu_startup_entry+0x60/0x134) from [<804fe9a4>] (0x804fe9a4) I don't have the hardware, so I wasn't able to reproduce the warning but after looking a while at the code, I deduced the following: 1. the CPU2 enters a deep idle state and sets the broadcast timer 2. the timer expires, the tick_handle_oneshot_broadcast function is called, setting the tick_broadcast_pending_mask and waking up the idle cpu CPU2 3. the CPU2 exits idle handles the interrupt and then invokes tick_broadcast_oneshot_control with CLOCK_EVENT_NOTIFY_EXIT which runs the following code: [...] if (dev->next_event.tv64 == KTIME_MAX) goto out; if (cpumask_test_and_clear_cpu(cpu, tick_broadcast_pending_mask)) goto out; [...] So if there is no next event scheduled for CPU2, we fulfil the first condition and jump out without clearing the tick_broadcast_pending_mask. 4. CPU2 goes to deep idle again and calls tick_broadcast_oneshot_control with CLOCK_NOTIFY_EVENT_ENTER but with the tick_broadcast_pending_mask set for CPU2, triggering the warning. The issue only surfaced due to the modifications of the cpuidle framework, which resulted in interrupts being enabled before the call to the clockevents code. If the call happens before interrupts have been enabled, the warning cannot trigger, because there is still the event pending which caused the broadcast timer expiry. Move the check for the next event below the check for the pending bit, so the pending bit gets cleared whether an event is scheduled on the cpu or not. [ tglx: Massaged changelog ] Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Reported-and-tested-by: NJoseph Lo <josephl@nvidia.com> Cc: Stephen Warren <swarren@nvidia.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linaro-kernel@lists.linaro.org Link: http://lkml.kernel.org/r/1371485735-31249-1-git-send-email-daniel.lezcano@linaro.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 31 5月, 2013 1 次提交
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由 Jiri Bohac 提交于
Since 7300711e ("clockevents: broadcast fixup possible waiters"), the timekeeping duty is assigned to the CPU that handles the tick broadcast clock device by the time it is set in one shot mode. This is an issue in full dynticks mode where the timekeeping duty must stay handled by the boot CPU for now. Otherwise it prevents secondary CPUs from offlining and this breaks suspend/shutdown/reboot/... As it appears there is no reason for this timekeeping duty to be moved to the broadcast CPU, besides nothing prevent it from being later re-assigned to another target, let's simply remove it. Signed-off-by: NJiri Bohac <jbohac@suse.cz> Reported-by: NSteven Rostedt <rostedt@goodmis.org> Acked-by: NThomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Signed-off-by: NIngo Molnar <mingo@kernel.org>
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- 28 5月, 2013 1 次提交
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由 Thomas Gleixner 提交于
commit 26517f3e (tick: Avoid programming the local cpu timer if broadcast pending) added a warning if the cpu enters broadcast mode again while the pending bit is still set. Meelis reported that the warning triggers. There are two corner cases which have been not considered: 1) cpuidle calls clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER) twice. That can result in the following scenario CPU0 CPU1 cpuidle_idle_call() clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER) set cpu in tick_broadcast_oneshot_mask broadcast interrupt event expired for cpu1 set pending bit acpi_idle_enter_simple() clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER) WARN_ON(pending bit) Move the WARN_ON into the section where we enter broadcast mode so it wont provide false positives on the second call. 2) safe_halt() enables interrupts, so a broadcast interrupt can be delivered befor the broadcast mode is disabled. That sets the pending bit for the CPU which receives the broadcast interrupt. Though the interrupt is delivered right away from the broadcast handler and leaves the pending bit stale. Clear the pending bit for the current cpu in the broadcast handler. Reported-and-tested-by: NMeelis Roos <mroos@linux.ee> Cc: Len Brown <lenb@kernel.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Rafael J. Wysocki <rjw@sisk.pl> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305271841130.4220@ionosSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 16 5月, 2013 3 次提交
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由 Thomas Gleixner 提交于
Split out the clockevent device selection logic. Preparatory patch to allow unbinding active clockevent devices. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Magnus Damm <magnus.damm@gmail.com> Link: http://lkml.kernel.org/r/20130425143436.431796247@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Thomas Gleixner 提交于
We want to be able to remove clockevent modules as well. Add a refcount so we don't remove a module with an active clock event device. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Magnus Damm <magnus.damm@gmail.com> Link: http://lkml.kernel.org/r/20130425143436.307435149@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Thomas Gleixner 提交于
7+ years and still a single user. Kill it. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Magnus Damm <magnus.damm@gmail.com> Link: http://lkml.kernel.org/r/20130425143436.098520211@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 05 5月, 2013 1 次提交
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由 Thomas Gleixner 提交于
commit b352bc1c (tick: Convert broadcast cpu bitmaps to cpumask_var_t) broke CONFIG_CPUMASK_OFFSTACK in a very subtle way. Instead of allocating the cpumasks with zalloc_cpumask_var it uses alloc_cpumask_var, so we can get random data there, which of course confuses the logic completely and causes random failures. Reported-and-tested-by: NDave Jones <davej@redhat.com> Reported-and-tested-by: NYinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305032015060.2990@ionosSigned-off-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NIngo Molnar <mingo@kernel.org>
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- 25 4月, 2013 1 次提交
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由 Thomas Gleixner 提交于
Vitaliy reported that a per cpu HPET timer interrupt crashes the system during hibernation. What happens is that the per cpu HPET timer gets shut down when the nonboot cpus are stopped. When the nonboot cpus are onlined again the HPET code sets up the MSI interrupt which fires before the clock event device is registered. The event handler is still set to hrtimer_interrupt, which then crashes the machine due to highres mode not being active. See http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=700333 There is no real good way to avoid that in the HPET code. The HPET code alrady has a mechanism to detect spurious interrupts when event handler == NULL for a similar reason. We can handle that in the clockevent/tick layer and replace the previous functional handler with a dummy handler like we do in tick_setup_new_device(). The original clockevents code did this in clockevents_exchange_device(), but that got removed by commit 7c1e7689 (clockevents: prevent clockevent event_handler ending up handler_noop) which forgot to fix it up in tick_shutdown(). Same issue with the broadcast device. Reported-by: NVitaliy Fillipov <vitalif@yourcmc.ru> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: stable@vger.kernel.org Cc: 700333@bugs.debian.org Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 18 4月, 2013 1 次提交
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由 Stephen Boyd 提交于
tick_oneshot_notify() is used to notify a particular CPU to try to switch into oneshot mode after a oneshot capable tick device is registered and tick_clock_notify() is used to notify all CPUs to try to switch into oneshot mode after a high res clocksource is registered. There is one caveat; if the tick devices suffer from FEAT_C3_STOP we don't try to switch into oneshot mode unless we have a oneshot capable broadcast device already registered. If the broadcast device is registered after the tick devices that have FEAT_C3_STOP we'll never try to switch into oneshot mode again, causing us to be stuck in periodic mode forever. Avoid this scenario by calling tick_clock_notify() after we register the broadcast device so that we try to switch into oneshot mode on all CPUs one more time. [ tglx: Adopted to timers/core and added a comment ] Signed-off-by: NStephen Boyd <sboyd@codeaurora.org> Link: http://lkml.kernel.org/r/1366219566-29783-1-git-send-email-sboyd@codeaurora.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 16 4月, 2013 1 次提交
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由 Frederic Weisbecker 提交于
"Extended nohz" was used as a naming base for the full dynticks API and Kconfig symbols. It reflects the fact the system tries to stop the tick in more places than just idle. But that "extended" name is a bit opaque and vague. Rename it to "full" makes it clearer what the system tries to do under this config: try to shutdown the tick anytime it can. The various constraints that prevent that to happen shouldn't be considered as fundamental properties of this feature but rather technical issues that may be solved in the future. Reported-by: NIngo Molnar <mingo@kernel.org> Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Kevin Hilman <khilman@linaro.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de>
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- 21 3月, 2013 1 次提交
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由 Frederic Weisbecker 提交于
This way the full nohz CPUs can safely run with the tick stopped with a guarantee that somebody else is taking care of the jiffies and GTOD progression. Once the duty is attributed to a CPU, it won't change. Also that CPU can't enter into dyntick idle mode or be hot unplugged. This may later be improved from a power consumption POV. At least we should be able to share the duty amongst all CPUs outside the full dynticks range. Then the duty could even be shared with full dynticks CPUs when those can't stop their tick for any reason. But let's start with that very simple approach first. Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Kevin Hilman <khilman@linaro.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> [fix have_nohz_full_mask offcase] Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
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- 13 3月, 2013 3 次提交
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由 Thomas Gleixner 提交于
On the CPU which gets woken along with the target CPU of the broadcast the following happens: deep_idle() <-- spurious wakeup broadcast_exit() set forced bit enable interrupts <-- Nothing happens disable interrupts broadcast_enter() <-- Here we observe the forced bit is set deep_idle() Now after that the target CPU of the broadcast runs the broadcast handler and finds the other CPU in both the broadcast and the forced mask, sends the IPI and stuff gets back to normal. So it's not actually harmful, just more evidence for the theory, that hardware designers have access to very special drug supplies. Now there is no point in going back to deep idle just to wake up again right away via an IPI. Provide a check which allows the idle code to avoid the deep idle transition. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: LAK <linux-arm-kernel@lists.infradead.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Arjan van de Veen <arjan@infradead.org> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Cc: Jason Liu <liu.h.jason@gmail.com> Link: http://lkml.kernel.org/r/20130306111537.565418308@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Thomas Gleixner 提交于
Some brilliant hardware implementations wake multiple cores when the broadcast timer fires. This leads to the following interesting problem: CPU0 CPU1 wakeup from idle wakeup from idle leave broadcast mode leave broadcast mode restart per cpu timer restart per cpu timer go back to idle handle broadcast (empty mask) enter broadcast mode programm broadcast device enter broadcast mode programm broadcast device So what happens is that due to the forced reprogramming of the cpu local timer, we need to set a event in the future. Now if we manage to go back to idle before the timer fires, we switch off the timer and arm the broadcast device with an already expired time (covered by forced mode). So in the worst case we repeat the above ping pong forever. Unfortunately we have no information about what caused the wakeup, but we can check current time against the expiry time of the local cpu. If the local event is already in the past, we know that the broadcast timer is about to fire and send an IPI. So we mark ourself as an IPI target even if we left broadcast mode and avoid the reprogramming of the local cpu timer. This still leaves the possibility that a CPU which is not handling the broadcast interrupt is going to reach idle again before the IPI arrives. This can't be solved in the core code and will be handled in follow up patches. Reported-by: NJason Liu <liu.h.jason@gmail.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: LAK <linux-arm-kernel@lists.infradead.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Arjan van de Veen <arjan@infradead.org> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Link: http://lkml.kernel.org/r/20130306111537.492045206@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Thomas Gleixner 提交于
If the local cpu timer stops in deep idle, we arm the broadcast device and get woken by an IPI. Now when we return from deep idle we reenable the local cpu timer unconditionally before handling the IPI. But that's a pointless exercise: the timer is already expired and the IPI is on the way. And it's an expensive exercise as we use the forced reprogramming mode so that we do not lose a timer event. This forced reprogramming will loop at least once in the retry. To avoid this reprogramming, we mark the cpu in a pending bit mask before we send the IPI. Now when the IPI target cpu wakes up, it will see the pending bit set and skip the reprogramming. The reprogramming of the cpu local timer will happen in the IPI handler which runs the cpu local timer interrupt function. Reported-by: NJason Liu <liu.h.jason@gmail.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: LAK <linux-arm-kernel@lists.infradead.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Arjan van de Veen <arjan@infradead.org> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Link: http://lkml.kernel.org/r/20130306111537.431082074@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 08 3月, 2013 1 次提交
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由 Mark Rutland 提交于
Currently tick_check_broadcast_device doesn't reject clock_event_devices with CLOCK_EVT_FEAT_DUMMY, and may select them in preference to real hardware if they have a higher rating value. In this situation, the dummy timer is responsible for broadcasting to itself, and the core clockevents code may attempt to call non-existent callbacks for programming the dummy, eventually leading to a panic. This patch makes tick_check_broadcast_device always reject dummy timers, preventing this problem. Signed-off-by: NMark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Jon Medhurst (Tixy) <tixy@linaro.org> Cc: stable@vger.kernel.org Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 07 3月, 2013 3 次提交
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由 Daniel Lezcano 提交于
When a cpu goes to a deep idle state where its local timer is shutdown, it notifies the time frame work to use the broadcast timer instead. Unfortunately, the broadcast device could wake up any CPU, including an idle one which is not concerned by the wake up at all. So in the worst case an idle CPU will wake up to send an IPI to the CPU whose timer expired. Provide an opt-in feature CLOCK_EVT_FEAT_DYNIRQ which tells the core that is should set the interrupt affinity of the broadcast interrupt to the cpu which has the earliest expiry time. This avoids unnecessary spurious wakeups and IPIs. [ tglx: Adopted to cpumask rework, silenced an uninitialized warning, massaged changelog ] Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Cc: viresh.kumar@linaro.org Cc: jacob.jun.pan@linux.intel.com Cc: linux-arm-kernel@lists.infradead.org Cc: santosh.shilimkar@ti.com Cc: linaro-kernel@lists.linaro.org Cc: patches@linaro.org Cc: rickard.andersson@stericsson.com Cc: vincent.guittot@linaro.org Cc: linus.walleij@stericsson.com Cc: john.stultz@linaro.org Link: http://lkml.kernel.org/r/1362219013-18173-3-git-send-email-daniel.lezcano@linaro.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Daniel Lezcano 提交于
Pass the broadcast timer to tick_broadcast_set_event() instead of reevaluating tick_broadcast_device.evtdev. [ tglx: Massaged changelog ] Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Cc: viresh.kumar@linaro.org Cc: jacob.jun.pan@linux.intel.com Cc: linux-arm-kernel@lists.infradead.org Cc: santosh.shilimkar@ti.com Cc: linaro-kernel@lists.linaro.org Cc: patches@linaro.org Cc: rickard.andersson@stericsson.com Cc: vincent.guittot@linaro.org Cc: linus.walleij@stericsson.com Cc: john.stultz@linaro.org Link: http://lkml.kernel.org/r/1362219013-18173-2-git-send-email-daniel.lezcano@linaro.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Thomas Gleixner 提交于
Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20130306111537.366394000@linutronix.de Cc: Rusty Russell <rusty@rustcorp.com.au>
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- 13 2月, 2013 1 次提交
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由 Mark Rutland 提交于
Commit 12ad1000: "clockevents: Add generic timer broadcast function" made tick_device_uses_broadcast set up the generic broadcast function for dummy devices (where !tick_device_is_functional(dev)), but neglected to set up the broadcast function for devices that stop in low power states (with the CLOCK_EVT_FEAT_C3STOP flag). When these devices enter low power states they will not have the generic broadcast function assigned, and will bring down the system when an attempt is made to broadcast to them. This patch ensures that the broadcast function is also assigned for devices which require broadcast in low power states. Reported-by: NStephen Warren <swarren@nvidia.com> Signed-off-by: NMark Rutland <mark.rutland@arm.com> Tested-by: NStephen Warren <swarren@nvidia.com> Cc: linux-arm-kernel@lists.infradead.org Cc: nico@linaro.org Cc: Marc.Zyngier@arm.com Cc: Will.Deacon@arm.com Cc: santosh.shilimkar@ti.com Cc: john.stultz@linaro.org Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 01 2月, 2013 2 次提交
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由 Mark Rutland 提交于
Currently, the timer broadcast mechanism is defined by a function pointer on struct clock_event_device. As the fundamental mechanism for broadcast is architecture-specific, this means that clock_event_device drivers cannot be shared across multiple architectures. This patch adds an (optional) architecture-specific function for timer tick broadcast, allowing drivers which may require broadcast functionality to be shared across multiple architectures. Signed-off-by: NMark Rutland <mark.rutland@arm.com> Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Cc: linux-arm-kernel@lists.infradead.org Cc: nico@linaro.org Cc: Will.Deacon@arm.com Cc: Marc.Zyngier@arm.com Cc: john.stultz@linaro.org Link: http://lkml.kernel.org/r/1358183124-28461-3-git-send-email-mark.rutland@arm.comTested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Reviewed-by: NStephen Boyd <sboyd@codeaurora.org> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Mark Rutland 提交于
Currently the broadcast mechanism used for timers is abstracted by a function pointer on struct clock_event_device. As the fundamental mechanism for broadcast is architecture-specific, this ties each clock_event_device driver to a single architecture, even where the driver is otherwise generic. This patch adds a standard path for the receipt of timer broadcasts, so drivers and/or architecture backends need not manage redundant lists of timers for the purpose of routing broadcast timer ticks. [tglx: Made the implementation depend on the config switch as well ] Signed-off-by: NMark Rutland <mark.rutland@arm.com> Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Cc: linux-arm-kernel@lists.infradead.org Cc: nico@linaro.org Cc: Will.Deacon@arm.com Cc: Marc.Zyngier@arm.com Cc: john.stultz@linaro.org Link: http://lkml.kernel.org/r/1358183124-28461-2-git-send-email-mark.rutland@arm.comTested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Reviewed-by: NStephen Boyd <sboyd@codeaurora.org> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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