Re: [PATCH 10/21] cpuidle: reduce code duplication inside cpuidle_idle_call()

From: Daniel Lezcano
Date: Wed Sep 25 2013 - 18:01:22 EST


On 09/22/2013 03:21 AM, Viresh Kumar wrote:
> We are doing this twice in cpuidle_idle_call() routine:
> drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP
>
> Would be better if we actually store this in a local variable and use that. That
> would remove code duplication as well as make this piece of code run fast (in
> case compiler wasn't able to optimize it earlier)
>
> Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>

Acked-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>

> ---
> drivers/cpuidle/cpuidle.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
> index b8c63cb..ed67e3c 100644
> --- a/drivers/cpuidle/cpuidle.c
> +++ b/drivers/cpuidle/cpuidle.c
> @@ -118,6 +118,7 @@ int cpuidle_idle_call(void)
> struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
> struct cpuidle_driver *drv;
> int next_state, entered_state;
> + bool broadcast;
>
> if (cpuidle_disabled() || !initialized)
> return -ENODEV;
> @@ -141,7 +142,9 @@ int cpuidle_idle_call(void)
>
> trace_cpu_idle_rcuidle(next_state, dev->cpu);
>
> - if (drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP)
> + broadcast = drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP;
> +
> + if (broadcast)
> clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER,
> &dev->cpu);
>
> @@ -151,7 +154,7 @@ int cpuidle_idle_call(void)
> else
> entered_state = cpuidle_enter_state(dev, drv, next_state);
>
> - if (drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP)
> + if (broadcast)
> clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT,
> &dev->cpu);
>
>


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