From mboxrd@z Thu Jan 1 00:00:00 1970 From: Viresh Kumar Subject: [PATCH V2 14/16] cpuidle: don't calculate time-diff if entered_state < 0 Date: Thu, 3 Oct 2013 21:26:53 +0530 Message-ID: <0a0c8e4c6fbf681d375f25b0c0eba036b8eaadf7.1380815504.git.viresh.kumar@linaro.org> References: Return-path: In-Reply-To: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org To: rjw@sisk.pl, daniel.lezcano@linaro.org Cc: linaro-kernel@lists.linaro.org, patches@linaro.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Viresh Kumar List-Id: linux-pm@vger.kernel.org If entered_state < 0, we don't need to set dev->last_residency to 'diff' as we will be setting it to zero without using its new value. And so move calculation of diff also inside the "if" statement. Acked-by: Daniel Lezcano Signed-off-by: Viresh Kumar --- drivers/cpuidle/cpuidle.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index b45257a..1a6e9f5 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -77,23 +77,22 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, struct cpuidle_state *target_state = &drv->states[index]; ktime_t time_start, time_end; - s64 diff; time_start = ktime_get(); entered_state = target_state->enter(dev, drv, index); - time_end = ktime_get(); + if (entered_state >= 0) { + s64 diff; - local_irq_enable(); + time_end = ktime_get(); + diff = ktime_to_us(ktime_sub(time_end, time_start)); - diff = ktime_to_us(ktime_sub(time_end, time_start)); - if (diff > INT_MAX) - diff = INT_MAX; + if (diff > INT_MAX) + diff = INT_MAX; - dev->last_residency = (int) diff; + dev->last_residency = (int) diff; - if (entered_state >= 0) { /* Update cpuidle counters */ /* This can be moved to within driver enter routine * but that results in multiple copies of same code. @@ -104,6 +103,8 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, dev->last_residency = 0; } + local_irq_enable(); + return entered_state; } -- 1.7.12.rc2.18.g61b472e