Re: [RFT][PATCH v4 3/7] sched: idle: Do not stop the tick before cpuidle_idle_call()

From: Rafael J. Wysocki
Date: Thu Mar 15 2018 - 17:13:05 EST


On Thu, Mar 15, 2018 at 9:41 PM, Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
> On Thu, Mar 15, 2018 at 7:19 PM, Frederic Weisbecker
> <frederic@xxxxxxxxxx> wrote:
>> On Mon, Mar 12, 2018 at 10:53:25AM +0100, Rafael J. Wysocki wrote:
>>> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>>>
>>> Make cpuidle_idle_call() decide whether or not to stop the tick.
>>>
>>> First, the cpuidle_enter_s2idle() path deals with the tick (and with
>>> the entire timekeeping for that matter) by itself and it doesn't need
>>> the tick to be stopped beforehand.
>>
>> Not sure you meant timekeeping either :)
>
> Yeah, I meant nohz.

Well, not really. :-)

It is the entire timekeeping this time, as it can be suspended
entirely in that code path.