Messages in this thread | | | From | Joel Fernandes <> | Date | Thu, 6 Jul 2017 22:26:36 -0700 | Subject | Re: [PATCH v2 3/6] cpufreq: schedutil: ensure max frequency while running RT/DL tasks |
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Hi,
On Wed, Jul 5, 2017 at 6:41 AM, Patrick Bellasi <patrick.bellasi@arm.com> wrote: [..] > >> But what about clearing the sched-class's flag from .pick_next_task() callback >> when they return NULL ? >> >> What about something like this instead (completely untested), with which we >> don't need the 2/3 patch as well: > > Just had a fast check but I think something like that can work. > We had an internal discussion with Brendan (in CC now) which had a > similar proposal. > > Main counter arguments for me was: > 1. we wanna to reduce the pollution of scheduling classes code with > schedutil specific code, unless strictly necessary > 2. we never had a "clear bit" semantics for flags updates > > Thus this proposal seemed to me less of a discontinuity wrt the > current interface. However, something similar to what you propose > below should also work. Let's collect some more feedback... >
I was going to say something similar. I feel its much cleaner if the scheduler clears the flags that it set, thus taking "ownership" of the flag. I feel that will avoid complication like this where the governor has to peek into what's currently running and such (and also help with the suggestion I made for patch 2/3.
Maybe the interface needs an extension for "clear flag" semantics?
thanks,
-Joel
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