Re: [PATCH] sched: do not stop ticks when cpu is not idle

[Ingo Molnar <mingo@elte.hu>]

* Ingo Molnar <mingo@elte.hu> wrote:

> --- a/kernel/sched.c
> +++ b/kernel/sched.c
> @@ -4446,7 +4446,8 @@ need_resched_nonpreemptible:
>  		rq->nr_switches++;
>  		rq->curr = next;
>  		++*switch_count;
> -
> +		if (rq->curr != rq->idle)
> +			tick_nohz_restart_sched_tick();
>  		context_switch(rq, prev, next); /* unlocks the rq */

hm, one problem i can see is lock dependencies. This code is executed 
with the rq lock while tick_nohz_restart_sched_tick() takes hr locks => 
not good. So i havent applied this just yet - this needs to be solved 
differently.

	Ingo