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

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Date:   Wed, 7 Jun 2023 12:50:08 +0100
From:   Hongyan Xia <hongyan.xia2@....com>
To:     Qais Yousef <qyousef@...alina.io>
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

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?

Hongyan