linux-kernel - Re: [PATCH v2 1/3] sched/uclamp: Set max_spare_cap_cpu even if max_spare

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Date:   Fri, 30 Jun 2023 12:44:03 +0100
From:   Qais Yousef <qyousef@...alina.io>
To:     Hongyan Xia <hongyan.xia2@....com>
Cc:     Ingo Molnar <mingo@...nel.org>,
        Peter Zijlstra <peterz@...radead.org>,
        Dietmar Eggemann <dietmar.eggemann@....com>,
        linux-kernel@...r.kernel.org, Lukasz Luba <lukasz.luba@....com>,
        Wei Wang <wvw@...gle.com>, Xuewen Yan <xuewen.yan94@...il.com>,
        Hank <han.lin@...iatek.com>,
        Jonathan JMChen <Jonathan.JMChen@...iatek.com>,
        Vincent Guittot <vincent.guittot@...aro.org>
Subject: Re: [PATCH v2 1/3] sched/uclamp: Set max_spare_cap_cpu even if
 max_spare_cap is 0

On 06/07/23 12:50, Hongyan Xia wrote:
> Hi Qais,
> 
> On 2023-02-11 17:28, Qais Yousef wrote:
> > On 02/07/23 10:45, Vincent Guittot wrote:
> > > [...]
> > 
> > Isn't it better to go back to v1 form then? The inconsistent type paired with
> > the cast isn't getting too ugly for me :(
> > 
> > I don't think we can convert cpu_cap to long without having to do more work as
> > it is used with 'util'.
> 
> Sorry if I'm missing something obvious, but why can't we convert util to
> long? The only place I see which mixes with util is
> 
> 	lsub_positive(&cpu_cap, util);
> 
> but at this point both cpu_cap and util should have sane values (top bit not
> set) so doing clamped subtraction should just work fine?

I completely have this series paged out now. I'll consider this comment when
I prepare v3 - which I hope I'll have some down time in few weeks time to send
some fixes I have been sitting on for a bit.


Cheers

--
Qais Yousef