Re: [RFC/RFT][PATCH v2 1/6] time: tick-sched: Reorganize idle tick management code
From: Rafael J. Wysocki
Date: Thu Mar 08 2018 - 04:21:53 EST
On Thursday, March 8, 2018 12:18:29 AM CET Frederic Weisbecker wrote:
> On Tue, Mar 06, 2018 at 10:02:01AM +0100, Rafael J. Wysocki wrote:
> > Index: linux-pm/kernel/time/tick-sched.c
> > ===================================================================
> > --- linux-pm.orig/kernel/time/tick-sched.c
> > +++ linux-pm/kernel/time/tick-sched.c
> > +
> > +/**
> > + * tick_nohz_idle_prepare - prepare for entering idle on the current CPU.
> > + *
> > + * Called when we start the idle loop.
> > + */
> > +void tick_nohz_idle_prepare(void)
> > +{
> > + struct tick_sched *ts;
> > +
> > + __tick_nohz_idle_prepare();
> > +
> > + local_irq_disable();
> > +
> > + ts = this_cpu_ptr(&tick_cpu_sched);
> > + ts->inidle = 1;
> > +
> > + local_irq_enable();
> > +}
>
> Why not calling tick_nohz_start_idle() from there? This is going to
> simplify the rest, you won't need to call tick_nohz_idle_go_idle()
> from places that don't want to stop the tick and you can then remove
> the stop_tick argument.
So I guess I would then use ts->idle_entrytime as "now" in the
tick_nohz_get_sleep_length() computation, right?