linux-kernel - Re: [PATCH v2] sched/uclamp: Fix overzealous type replacement

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Message-ID: <f4fcc45e-7609-3836-162a-0a1839134bcf@arm.com>
Date:   Fri, 15 Nov 2019 14:29:44 +0000
From:   Valentin Schneider <valentin.schneider@....com>
To:     Vincent Guittot <vincent.guittot@...aro.org>
Cc:     linux-kernel <linux-kernel@...r.kernel.org>,
        Ingo Molnar <mingo@...nel.org>,
        Peter Zijlstra <peterz@...radead.org>,
        Dietmar Eggemann <Dietmar.Eggemann@....com>,
        Tejun Heo <tj@...nel.org>,
        Patrick Bellasi <patrick.bellasi@...bug.net>,
        Suren Baghdasaryan <surenb@...gle.com>,
        Quentin Perret <qperret@...gle.com>,
        Qais Yousef <qais.yousef@....com>
Subject: Re: [PATCH v2] sched/uclamp: Fix overzealous type replacement

On 15/11/2019 14:07, Vincent Guittot wrote:
>> -static inline enum uclamp_id uclamp_none(enum uclamp_id clamp_id)
>> +static inline unsigned int uclamp_none(enum uclamp_id clamp_id)
> 
> Out of curiosity why uclamp decided to use unsigned int to manipulate
> utilization instead of unsigned long which is the type of util_avg ?
> 

I didn't stare at the discussion much, but I think it stems from the
design choices behind struct uclamp_se: everything is crammed in an unsigned
int bitfield. Let me see if I can find some relevant mails.