Messages in this thread | | | Date | Tue, 2 Feb 2016 09:50:41 +0900 | From | Byungchul Park <> | Subject | Re: [PATCH 1/4] sched: Don't account tickless CPU load on tick |
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On Mon, Feb 01, 2016 at 11:34:33AM +0100, Peter Zijlstra wrote: > On Mon, Feb 01, 2016 at 07:05:13PM +0900, Byungchul Park wrote: > > On Fri, Jan 29, 2016 at 10:50:16AM +0100, Peter Zijlstra wrote: > > > On Thu, Jan 28, 2016 at 05:01:26PM +0100, Frederic Weisbecker wrote: > > > > So lets check all the things we call on scheduler_tick(): > > > > > > > > _ sched_clock_tick(): maybe it doesn't need to be called when idle. I'm not sure. > > > > Some code in idle (timers, irqs, ...) might need to call sched_clock(). > > > > > > Only needed if you've got a shady TSC. > > > > Yeh.. IMO, this can be done without the tick handling during nohz, with the > > patch I am attaching. Could you check the patch? Or we have to handle it > > remotely, too. (for a crazy TSC) > > I think NOHZ_FULL already requires the TSC not to be wrecked.
What about the regular NOHZ? Or does not any code in idle call a kind of sched_lock_cpu() at all?
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