Re: [PATCH 2/4] sched: cpufreq: Keep track of cpufreq utilization update flags

On 17-12-17, 01:19, Rafael J. Wysocki wrote:

We can do that in principle, but why should it return early?  Maybe it's
a good time to update things, incidentally?

I actually don't like the SCHED_CPUFRREQ_CLEAR flag *concept* as it is very
much specific to schedutil and blatantly ignores everybody else.

Alternatively, you could add two flags for clearing SCHED_CPUFREQ_RT and
SCHED_CPUFREQ_DL that could just be ingored entirely by intel_pstate.

So, why don't you make SCHED_CPUFREQ_RT and SCHED_CPUFREQ_DL "sticky" until,
say, SCHED_CPUFREQ_NO_RT and SCHED_CPUFREQ_NO_DL are passed, respectively?

I didn't like adding scheduling class specific flags, and wanted the code to
treat all of them in the same way. And then the governors can make a policy over
that, on what to ignore and what not to. For example with the current patchset,
the governors can know when nothing else is queued on a CPU and CPU is going to
get into idle loop. They can choose to (or not to) do something in that case.

I just thought that writing consistent (i.e. no special code) code across all
classes would be better.

-- 
viresh