Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Fri, 26 Jun 2020 08:02:19 +0530
From:   Viresh Kumar <viresh.kumar@linaro.org>
To:     Wei Wang <wvw@google.com>
Cc:     Wei Wang <wei.vince.wang@gmail.com>, dsmythies@telus.net,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
        "Joel Fernandes (Google)" <joel@joelfernandes.org>,
        Linux PM list <linux-pm@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] cpufreq: schedutil: force frequency update when limits
 change
Message-ID: <20200626023219.wvhzomwzlw24bzrv@vireshk-i7>
References: <20200625064614.101183-1-wvw@google.com>
 <20200625102305.gu3xo4ovcqyd35vd@vireshk-i7>
 <CAGXk5yrA=oXZs9KAaELsO7+ex7xCggEwdWSC_KXrUWQnvKEpWQ@mail.gmail.com>
 <20200626021428.tnecyy3wt42slvik@vireshk-i7>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20200626021428.tnecyy3wt42slvik@vireshk-i7>
User-Agent: NeoMutt/20180716-391-311a52
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 26-06-20, 07:44, Viresh Kumar wrote:
> On 25-06-20, 13:47, Wei Wang wrote:
> > On Thu, Jun 25, 2020 at 3:23 AM Viresh Kumar <viresh.kumar@linaro.org> wrote:
> > > I am sorry but I am not fully sure of what the problem is. Can you
> > > describe that by giving an example with some random frequency, and
> > > tell the expected and actual behavior ?
> > >
> > The problem is sugov thought next_freq already updated (but actually
> > skipped by the rate limit thing) and all following updates will be
> > skipped.

The rate-limiting thing is specific to android and not present in
mainline. Even in android I see next_freq getting updated only after
rate-limiting is verified.

I think you maybe trying to fix an android only problem in mainline,
which may not be required at all. And I am not sure if Android has a
problem as well :)

> I am sorry, can you please give a detailed example with existing
> frequency and limits, then the limits changed to new values, then what
> exactly happens ?
> 
> > Actually this is specifically for Android common kernel 4.19's issue
> > which has sugov_up_down_rate_limit in sugov_update_next_freq, let's
> > continue discussion there.
> 
> If it is a mainline problem, we will surely get it fixed here. Just
> that I am not able to understand the problem yet. Sorry about that.

-- 
viresh