From: Valentin Schneider <valentin.schneider@arm.com>
To: Quentin Perret <qperret@google.com>
Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
x86@kernel.org, hpa@zytor.com, sudeep.holla@arm.com,
gregkh@linuxfoundation.org, rafael@kernel.org,
viresh.kumar@linaro.org, peterz@infradead.org,
juri.lelli@redhat.com, vincent.guittot@linaro.org,
dietmar.eggemann@arm.com, rostedt@goodmis.org,
bsegall@google.com, mgorman@suse.de, mcgrof@kernel.org,
keescook@chromium.org, yzaikin@google.com, fweisbec@gmail.com,
tkjos@google.com, kernel-team@android.com,
Ionela Voinescu <ionela.voinescu@arm.com>
Subject: Re: [PATCH 00/14] Modularize schedutil
Date: Fri, 08 May 2020 15:52:07 +0100 [thread overview]
Message-ID: <jhjeerutr6w.mognet@arm.com> (raw)
In-Reply-To: <20200508131508.GB10541@google.com>
On 08/05/20 14:15, Quentin Perret wrote:
> Hey Valentin,
>
> On Thursday 07 May 2020 at 22:34:17 (+0100), Valentin Schneider wrote:
>> I'm curious; why would some Android device not want to roll with schedutil?
>>
>> When it comes to dynamic policies (i.e. forget performance / powersave, and
>> put userspace in a corner), I'd be willing to take a stand and say you
>> should only really be using schedutil nowadays - alignment with the
>> scheduler, uclamp, yadda yadda.
>>
>> AFAIA the only schedutil-related quirk we oughta fix for arm/arm64 is that
>> arch_scale_freq_invariant() thingie, and FWIW I'm hoping to get something
>> regarding this out sometime soonish. After that, I'd actually want to make
>> schedutil the default governor for arm/arm64.
>
> As in setting CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL=y in the arm64
> defconfig? If so, you have my Acked-by already :)
>
I'm actually thinking of making it the unconditional default for arm/arm64
in cpufreq's Kconfig, following what has been recently done for
intel_pstate.
>> I'm not opiniated on the modularization, but if you can, could you please
>> share some more details as to why schedutil cannot fulfill its role of holy
>> messiah of governors for GKI?
>
> I guess I answered some of that in the other thread with Peter, but all
> in all I'm definitely not trying to make an argument that schedutil
> isn't good enough here. I'm trying to say that mandating it in *GKI* is
> just likely to cause unnecessary friction, and trust me there is already
> enough of that with other topics.
Right, I appreciate it must be an "interesting" tug of war. My own opinion
has also already been expanded in the rest of the thread; i.e. we should
strive to make schedutil good enough that folks don't feel like they still
need to use ondemand/whatever frankengov. That said, even without GKI, I
get that making some vendors change their already tested-and-tuned setup is
an obstacle course in and of itself.
> Giving the option of having sugov as a
> module doesn't prevent us from making it a default for a few arches, so
> I think there is ground for an agreement!
>
> Cheers,
> Quentin
next prev parent reply other threads:[~2020-05-08 14:52 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-07 18:09 [PATCH 00/14] Modularize schedutil Quentin Perret
2020-05-07 18:09 ` [PATCH 01/14] sched: Provide sched_set_deadline() Quentin Perret
2020-05-07 18:10 ` [PATCH 02/14] sched: cpufreq: Use sched_set_deadline() from sugov Quentin Perret
2020-05-07 18:10 ` [PATCH 03/14] sched: cpufreq: Introduce 'want_eas' governor flag Quentin Perret
2020-05-07 18:10 ` [PATCH 04/14] sched: cpufreq: Move sched_cpufreq_governor_change() Quentin Perret
2020-05-08 5:35 ` Pavan Kondeti
2020-05-08 13:18 ` Quentin Perret
2020-05-07 18:10 ` [PATCH 05/14] sched: cpufreq: Move schedutil_cpu_util() Quentin Perret
2020-05-07 18:10 ` [PATCH 06/14] arch_topology: Export cpu_scale per-cpu array Quentin Perret
2020-05-07 18:10 ` [PATCH 07/14] kthread: Export kthread_bind_mask() Quentin Perret
2020-05-07 18:10 ` [PATCH 08/14] sched/core: Export runqueues per-cpu array Quentin Perret
2020-05-08 8:07 ` Peter Zijlstra
2020-05-08 10:04 ` Quentin Perret
2020-05-07 18:10 ` [PATCH 09/14] sched/cpufreq: Export cpufreq_this_cpu_can_update() Quentin Perret
2020-05-07 18:10 ` [PATCH 10/14] sched/fair: Export cpu_util_freq() Quentin Perret
2020-05-07 18:10 ` [PATCH 11/14] tick/sched: Export tick_nohz_get_idle_calls_cpu Quentin Perret
2020-05-07 18:10 ` [PATCH 12/14] x86: Export arch_scale_freq_key Quentin Perret
2020-05-07 18:10 ` [PATCH 13/14] sched: cpufreq: Use IS_ENABLED() for schedutil Quentin Perret
2020-05-08 5:30 ` Pavan Kondeti
2020-05-08 13:21 ` Quentin Perret
2020-05-09 2:43 ` Pavan Kondeti
2020-05-07 18:10 ` [PATCH 14/14] sched: cpufreq: Modularize schedutil Quentin Perret
2020-05-07 21:34 ` [PATCH 00/14] " Valentin Schneider
2020-05-08 13:15 ` Quentin Perret
2020-05-08 14:52 ` Valentin Schneider [this message]
2020-05-08 5:33 ` Viresh Kumar
2020-05-08 13:18 ` Quentin Perret
2020-05-08 8:11 ` Peter Zijlstra
2020-05-08 10:37 ` Greg KH
2020-05-08 11:16 ` Quentin Perret
2020-05-08 11:31 ` Peter Zijlstra
2020-05-08 13:05 ` Quentin Perret
2020-05-08 13:40 ` Rafael J. Wysocki
2020-05-11 9:00 ` Quentin Perret
2020-05-11 15:26 ` Rafael J. Wysocki
2020-05-12 9:21 ` Quentin Perret
2020-05-12 10:25 ` Rafael J. Wysocki
2020-05-12 13:58 ` Quentin Perret
2020-05-12 14:08 ` Rafael J. Wysocki
2020-05-12 15:11 ` Quentin Perret
2020-05-12 15:30 ` Rafael J. Wysocki
2020-05-12 15:49 ` Joel Fernandes
2020-05-13 8:57 ` Quentin Perret
2020-05-12 16:26 ` Quentin Perret
2020-05-12 17:30 ` Rafael J. Wysocki
2020-05-13 9:41 ` Quentin Perret
2020-05-13 10:02 ` Greg KH
2020-05-13 10:06 ` Quentin Perret
2020-05-13 10:24 ` Greg KH
2020-05-08 14:09 ` Peter Zijlstra
2020-05-11 9:12 ` Quentin Perret
2020-05-08 11:26 ` Peter Zijlstra
2020-05-11 5:21 ` Viresh Kumar
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=jhjeerutr6w.mognet@arm.com \
--to=valentin.schneider@arm.com \
--cc=bp@alien8.de \
--cc=bsegall@google.com \
--cc=dietmar.eggemann@arm.com \
--cc=fweisbec@gmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=hpa@zytor.com \
--cc=ionela.voinescu@arm.com \
--cc=juri.lelli@redhat.com \
--cc=keescook@chromium.org \
--cc=kernel-team@android.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=mcgrof@kernel.org \
--cc=mgorman@suse.de \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=qperret@google.com \
--cc=rafael@kernel.org \
--cc=rostedt@goodmis.org \
--cc=sudeep.holla@arm.com \
--cc=tglx@linutronix.de \
--cc=tkjos@google.com \
--cc=vincent.guittot@linaro.org \
--cc=viresh.kumar@linaro.org \
--cc=x86@kernel.org \
--cc=yzaikin@google.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).