From: Daniel Lezcano <daniel.lezcano@linaro.org>
To: Viresh Kumar <viresh.kumar@linaro.org>, rjw@sisk.pl
Cc: linaro-kernel@lists.linaro.org, patches@linaro.org,
linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 20/21] cpuidle: don't calculate time-diff if entered_state == 0
Date: Thu, 26 Sep 2013 00:38:50 +0200 [thread overview]
Message-ID: <524365FA.4090108@linaro.org> (raw)
In-Reply-To: <acd1cc837f969a50582d2b25a73c5e247f40f843.1379779777.git.viresh.kumar@linaro.org>
On 09/22/2013 03:21 AM, Viresh Kumar wrote:
> 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.
I don't get it, can you elaborate. We can be a long time in this state
(eg. if the prediction is false).
> And so move calculation of diff also inside the "if" statement.
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
> 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 bf80236..cb81689 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;
> }
>
>
--
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next prev parent reply other threads:[~2013-09-25 22:38 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-22 1:20 [PATCH 00/21] CPUIdle: Minor cleanups for 3.13 Viresh Kumar
2013-09-22 1:20 ` [PATCH 01/21] cpuidle: fix indentation of cpumask Viresh Kumar
2013-09-22 1:20 ` [PATCH 02/21] cpuidle: Fix comments in cpuidle core Viresh Kumar
2013-09-22 1:20 ` [PATCH 03/21] cpuidle: make __cpuidle_get_cpu_driver() inline Viresh Kumar
2013-09-25 21:27 ` Daniel Lezcano
2013-09-22 1:20 ` [PATCH 04/21] cpuidle: make __cpuidle_device_init() return void Viresh Kumar
2013-09-22 1:20 ` [PATCH 05/21] cpuidle: make __cpuidle_driver_init() " Viresh Kumar
2013-09-23 9:58 ` Hongbo Zhang
2013-09-23 10:02 ` Viresh Kumar
2013-09-22 1:20 ` [PATCH 06/21] cpuidle: rearrange code in __cpuidle_driver_init() Viresh Kumar
2013-09-25 21:40 ` Daniel Lezcano
2013-09-26 5:01 ` Viresh Kumar
2013-09-22 1:20 ` [PATCH 07/21] cpuidle: rearrange __cpuidle_register_device() to keep minimal exit points Viresh Kumar
2013-09-25 21:49 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 08/21] cpuidle: use cpuidle_disabled() instead of "off" Viresh Kumar
2013-09-25 21:52 ` Daniel Lezcano
2013-09-26 5:06 ` Viresh Kumar
2013-09-26 8:25 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 09/21] cpuidle: merge two if() statements for checking error cases Viresh Kumar
2013-09-25 21:52 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 10/21] cpuidle: reduce code duplication inside cpuidle_idle_call() Viresh Kumar
2013-09-25 22:01 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 11/21] cpuidle: replace multiline statements with single line in cpuidle_idle_call() Viresh Kumar
2013-09-25 22:03 ` Daniel Lezcano
2013-09-26 5:51 ` Viresh Kumar
2013-09-26 7:55 ` Daniel Lezcano
2013-09-26 8:11 ` Viresh Kumar
2013-09-22 1:21 ` [PATCH 12/21] cpuidle: call cpuidle_get_driver() from after taking cpuidle_driver_lock Viresh Kumar
2013-09-25 22:04 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 13/21] cpuidle: use drv instead of cpuidle_driver in show_current_driver() Viresh Kumar
2013-09-25 22:05 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 14/21] cpuidle: coupled: don't compare cpu masks unnecessarily Viresh Kumar
2013-09-25 22:06 ` Daniel Lezcano
2013-09-26 0:25 ` Colin Cross
2013-09-26 6:36 ` Viresh Kumar
2013-09-26 6:50 ` Colin Cross
2013-09-22 1:21 ` [PATCH 15/21] cpuidle: free all state kobjects from cpuidle_free_state_kobj() Viresh Kumar
2013-09-25 22:09 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 16/21] cpuidle: avoid unnecessary kzalloc/free of struct cpuidle_device_kobj Viresh Kumar
2013-09-25 22:12 ` Daniel Lezcano
2013-09-26 6:05 ` Viresh Kumar
2013-09-26 8:30 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 17/21] cpuidle: avoid unnecessary kzalloc/free of struct cpuidle_driver_kobj Viresh Kumar
2013-09-25 22:16 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 18/21] cpuidle: don't call poll_idle_init() for every cpu Viresh Kumar
2013-09-25 22:22 ` Daniel Lezcano
2013-09-26 6:09 ` Viresh Kumar
2013-09-26 8:28 ` Daniel Lezcano
2013-10-03 10:33 ` Viresh Kumar
2013-10-03 11:46 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 19/21] cpuidle: create list of registered drivers Viresh Kumar
2013-09-25 22:30 ` Daniel Lezcano
2013-09-26 6:17 ` Viresh Kumar
2013-09-26 8:19 ` Daniel Lezcano
2013-09-28 21:33 ` Paul E. McKenney
2013-09-30 18:37 ` Daniel Lezcano
2013-10-03 4:38 ` Viresh Kumar
2013-10-03 10:47 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 20/21] cpuidle: don't calculate time-diff if entered_state == 0 Viresh Kumar
2013-09-25 22:38 ` Daniel Lezcano [this message]
2013-09-26 6:24 ` Viresh Kumar
2013-09-26 8:25 ` Daniel Lezcano
2013-09-26 8:28 ` Viresh Kumar
2013-09-26 8:33 ` Daniel Lezcano
2013-09-22 1:21 ` [PATCH 21/21] cpuidle: change governor from within cpuidle_replace_governor() Viresh Kumar
2013-09-25 22:50 ` Daniel Lezcano
2013-09-26 6:37 ` Viresh Kumar
2013-09-26 8:20 ` Daniel Lezcano
2013-10-03 10:36 ` Viresh Kumar
2013-10-03 11:58 ` Daniel Lezcano
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