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Date:   Wed, 24 Jun 2020 14:28:19 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Patrick Bellasi <patrick.bellasi@matbug.net>
Cc:     Qais Yousef <qais.yousef@arm.com>, Ingo Molnar <mingo@redhat.com>,
        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>,
        Chris Redpath <chris.redpath@arm.com>,
        Lukasz Luba <lukasz.luba@arm.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 2/2] sched/uclamp: Protect uclamp fast path code with
 static key
Message-ID: <20200624122819.GG4781@hirez.programming.kicks-ass.net>
References: <20200619172011.5810-1-qais.yousef@arm.com>
 <20200619172011.5810-3-qais.yousef@arm.com>
 <87pn9oor2t.derkling@matbug.net>
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On Wed, Jun 24, 2020 at 09:34:02AM +0200, Patrick Bellasi wrote:
> > +static DEFINE_STATIC_KEY_TRUE(sched_uclamp_unused);
> 
> I would personally prefer a non negated semantic.

That's what I said earlier as well.


> > +	 */
> > +	if (static_branch_likely(&sched_uclamp_unused))
> > +		return;
> 
> Moreover, something like:
> 
>        if (static_key_false(&sched_uclamp_enabled))
>                 return;
> 
> is not just good enough?

static_key_true/false() are the deprecated API.