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Date:   Wed, 13 Mar 2019 18:22:28 +0000
From:   Patrick Bellasi <patrick.bellasi@arm.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
        linux-api@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        Tejun Heo <tj@kernel.org>,
        "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
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        Joel Fernandes <joelaf@google.com>,
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        Suren Baghdasaryan <surenb@google.com>
Subject: Re: [PATCH v7 01/15] sched/core: uclamp: Add CPU's clamp buckets
 refcounting
Message-ID: <20190313182228.h22o36vnokiskhzk@e110439-lin>
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On 13-Mar 18:22, Peter Zijlstra wrote:
> On Wed, Mar 13, 2019 at 04:12:29PM +0000, Patrick Bellasi wrote:
> > Yes, the for looks better, but perhaps like that:
> > 
> > 	unsigned int bucket_id = UCLAMP_BUCKETS;
> > 
> >  	/*
> >  	 * Both min and max clamps are MAX aggregated, thus the topmost
> >  	 * bucket with some tasks defines the rq's clamp value.
> >  	 */
> > 	for (; bucket_id >= 0; --bucket_id) {
> 
> GCC will be clever and figure that unsigned will never be smaller than 0
> and turn the above into an infinite loop or something daft.
> 
> That is; use 'int', not 'unsigned int' for bucket_id.

Right, which remembers me now why I originally went for a do { } while();

-- 
#include <best/regards.h>

Patrick Bellasi