From mboxrd@z Thu Jan 1 00:00:00 1970 From: daniel.lezcano@linaro.org (Daniel Lezcano) Date: Fri, 15 Mar 2013 15:27:00 +0100 Subject: [RFC patch 01/11] cpuidle : handle clockevent notify from the cpuidle framework In-Reply-To: <1363357630-22214-1-git-send-email-daniel.lezcano@linaro.org> References: <1363357630-22214-1-git-send-email-daniel.lezcano@linaro.org> Message-ID: <1363357630-22214-2-git-send-email-daniel.lezcano@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org When a cpu enters a deep idle state, the local timers are stopped and the time framework falls back to the timer device used as a broadcast timer. The different cpuidle drivers are calling clockevents_notify ENTER/EXIT when the idle state stops the local timer. The proposed patch introduces a new flag CPUIDLE_FLAG_TIMER_STOP to let the cpuidle framework to call clockevents_notify instead of duplicating again and again these lines in all the cpuidle drivers. Signed-off-by: Daniel Lezcano --- drivers/cpuidle/cpuidle.c | 9 +++++++++ include/linux/cpuidle.h | 1 + 2 files changed, 10 insertions(+) diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index eba6929..c500370 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -8,6 +8,7 @@ * This code is licenced under the GPL. */ +#include #include #include #include @@ -146,12 +147,20 @@ int cpuidle_idle_call(void) trace_cpu_idle_rcuidle(next_state, dev->cpu); + if (drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP) + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, + &dev->cpu); + if (cpuidle_state_is_coupled(dev, drv, next_state)) entered_state = cpuidle_enter_state_coupled(dev, drv, next_state); else entered_state = cpuidle_enter_state(dev, drv, next_state); + if (drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP) + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, + &dev->cpu); + trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu); /* give the governor an opportunity to reflect on the outcome */ diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index 480c14d..a837b33 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -57,6 +57,7 @@ struct cpuidle_state { /* Idle State Flags */ #define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */ #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */ +#define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */ #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) -- 1.7.9.5