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, 19 Feb 2021 14:41:40 +0800
From:   Yue Hu <zbestahu@gmail.com>
To:     Viresh Kumar <viresh.kumar@linaro.org>
Cc:     rjw@rjwysocki.net, mingo@redhat.com, peterz@infradead.org,
        juri.lelli@redhat.com, vincent.guittot@linaro.org,
        dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com,
        linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org,
        huyue2@yulong.com, zbestahu@163.com
Subject: Re: [PATCH] cpufreq: schedutil: Don't consider freq reduction to
 busy CPU if need_freq_update is set
Message-ID: <20210219144140.00004de9.zbestahu@gmail.com>
In-Reply-To: <20210219040933.2o5hhbjb6emf3xl4@vireshk-i7>
References: <20210218082514.1437-1-zbestahu@gmail.com>
        <20210218102029.syj6vkltlbtoxsig@vireshk-i7>
        <20210219113804.00004a7e.zbestahu@gmail.com>
        <20210219040933.2o5hhbjb6emf3xl4@vireshk-i7>
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Precedence: bulk

On Fri, 19 Feb 2021 09:39:33 +0530
Viresh Kumar <viresh.kumar@linaro.org> wrote:

> On 19-02-21, 11:38, Yue Hu wrote:
> > There's a possibility: we will use the previous freq to update if
> > next_f is reduced for busy CPU if need_freq_update is set in
> > sugov_update_next_freq().  
> 
> Right.
> 
> > This possibility would happen now? And this
> > update is what we want if it happens?  
> 
> This is exactly what we want here, don't reduce speed for busy CPU,

I understand it should not skip this update but set the same freq as
previous one again for the specail case if need_freq_update is set. Am
i rt?

> but we also need to make sure we are in the policy's valid range
> which cpufreq core will take care of.
> 
> > This is related to another possible patch ready to send.  
> 
> I am not sure what's there to send now.

I will send later after figure out the doubt above.

>