Messages in this thread | | | Date | Wed, 9 May 2018 10:41:47 +0200 | From | Juri Lelli <> | Subject | Re: [RFC PATCH] sched/cpufreq/schedutil: handling urgent frequency requests |
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On 09/05/18 10:25, Rafael J. Wysocki wrote: > On Wed, May 9, 2018 at 10:23 AM, Juri Lelli <juri.lelli@redhat.com> wrote: > > On 09/05/18 10:05, Rafael J. Wysocki wrote: > >> On Wed, May 9, 2018 at 9:01 AM, Joel Fernandes <joel@joelfernandes.org> wrote: > >> > On Wed, May 09, 2018 at 12:24:49PM +0530, Viresh Kumar wrote: > >> >> On 09-05-18, 08:45, Juri Lelli wrote: > >> >> > On 08/05/18 21:54, Joel Fernandes wrote: > >> >> > Isn't this potentially introducing unneeded irq pressure (and doing the > >> >> > whole wakeup the kthread thing), while the already active kthread could > >> >> > simply handle multiple back-to-back requests before going to sleep? > >> >> > >> >> And then we may need more instances of the work item and need to store > >> >> a different value of next_freq with each work item, as we can't use > >> >> the common one anymore as there would be races around accessing it ? > >> > > >> > Exactly. I think it also doesn't make sense to over write an already > >> > committed request either so better to store them separate (?). After the > >> > "commit", that previous request is done.. > >> > >> Why is it? > >> > >> In the non-fast-switch case the "commit" only means queuing up an > >> irq_work. Which BTW is one of the reasons for having work_in_progress > >> even if your kthread can handle multiple work items in one go. > >> > >> You may try to clear work_in_progress in sugov_irq_work() instead of > >> in sugov_work(), though. > >> > >> BTW, I'm not sure if the comment in sugov_irq_work() still applies. Juri? > > > > It doesn't anymore. sugov kthreads are now being "ignored". Should have > > remove it with the DL set of changes, sorry about that. > > No worries, you can still do that. ;-)
Indeed! Done. :)
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