Messages in this thread |  | | Date | Wed, 9 Apr 2014 21:26:51 +0530 | Subject | Re: nohz problem with idle time on old hardware | From | Viresh Kumar <> |
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On 9 April 2014 21:09, Steven Rostedt <rostedt@goodmis.org> wrote: > Reading even more of the code, now I'm totally confused :-)
:)
> When tick_setup_sched_timer() is called, if tick_nohz_enabled is set, > then we set tick_nohz_active.
correct.
> This gets called by hrtimer_switch_to_hres(), and before that is > called, the tick_check_oneshot_changed() will never get to the > tick_nohz_switch_to_nohz() call.
If hrtimer_switch_to_hres() is called or HRES is enabled, we will never ever call tick_nohz_switch_to_nohz().
> Looks to me, the real answer is to nuke both the if statement *and* the > setting of the tick_nohz_active in that function. Both looks a bit > redundant to me.
When HRES isn't enabled and NOHZ isn't enabled as well, in that case we should stick to the periodic code from tick-common.c and the oneshot options of tick_nohz_switch_to_nohz() or hrtimer_switch_to_hres() shouldn't be used. And so, we still need those checks, as per my understanding. :)
Lets see what others have for this discussion :)
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