Messages in this thread | | | From | "Rafael J. Wysocki" <> | Subject | Re: [PATCH 0/3] cpuidle: updates related to tick_broadcast_enter() failures | Date | Tue, 12 May 2015 01:14:01 +0200 |
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On Monday, May 11, 2015 04:13:37 PM Sudeep Holla wrote: > > On 10/05/15 00:15, Rafael J. Wysocki wrote: > > On Saturday, May 09, 2015 10:33:05 PM Rafael J. Wysocki wrote: > >> On Saturday, May 09, 2015 10:11:41 PM Rafael J. Wysocki wrote: > >>> On Saturday, May 09, 2015 11:19:16 AM Preeti U Murthy wrote: > >>>> Hi Rafael, > >>>> > >>>> On 05/08/2015 07:48 PM, Rafael J. Wysocki wrote: > >>> > >>> [cut] > >>> > >>>>>> > >>>>>> + /* Take note of the planned idle state. */ > >>>>>> + idle_set_state(smp_processor_id(), target_state); > >>>>> > >>>>> And I wouldn't do this either. > >>>>> > >>>>> The behavior here is pretty much as though the driver demoted the state chosen > >>>>> by the governor and we don't call idle_set_state() again in those cases. > >>>> > >>>> Why is this wrong? > >>> > >>> It is not "wrong", but incomplete, because demotions done by the cpuidle driver > >>> should also be taken into account in the same way. > >>> > >>> But I'm seeing that the recent patch of mine that made cpuidle_enter_state() > >>> call default_idle_call() was a mistake, because it might confuse find_idlest_cpu() > >>> significantly as to what state the CPU is in. I'll drop that one for now. > >> > >> OK, done. > >> > >> So after I've dropped it I think we need to do three things: > >> (1) Move the idle_set_state() calls to cpuidle_enter_state(). > >> (2) Make cpuidle_enter_state() call default_idle_call() again, but this time > >> do that *before* it has called idle_set_state() for target_state. > >> (3) Introduce demotion as per my last patch. > >> > >> Let me cut patches for that. > > > > Done as per the above and the patches follow in replies to this messge. > > > > All on top of the current linux-next branch of the linux-pm.git tree. > > > > Tested on ARM Vexpress platforms with one of the CPU in broadcast mode > and also with broadcast timer. So, you can add: > > Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Thanks!
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