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Date:   Fri, 10 Jan 2020 14:55:47 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     Wang Long <w@laoqinren.net>, mingo@redhat.com,
        juri.lelli@redhat.com, vincent.guittot@linaro.org,
        dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com,
        mgorman@suse.de, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sched/psi: create /proc/pressure and
 /proc/pressure/{io|memory|cpu} only when psi enabled
Message-ID: <20200110135547.GN2844@hirez.programming.kicks-ass.net>
References: <1576672698-32504-1-git-send-email-w@laoqinren.net>
 <20200108135526.GH2844@hirez.programming.kicks-ass.net>
 <20200109153002.GA8547@cmpxchg.org>
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On Thu, Jan 09, 2020 at 10:30:02AM -0500, Johannes Weiner wrote:
> On Wed, Jan 08, 2020 at 02:55:26PM +0100, Peter Zijlstra wrote:
> > On Wed, Dec 18, 2019 at 08:38:18PM +0800, Wang Long wrote:
> > > when CONFIG_PSI_DEFAULT_DISABLED set to N or the command line set psi=0,
> > > I think we should not create /proc/pressure and
> > > /proc/pressure/{io|memory|cpu}.
> > > 
> > > In the future, user maybe determine whether the psi feature is enabled by
> > > checking the existence of the /proc/pressure dir or
> > > /proc/pressure/{io|memory|cpu} files.
> > 
> > Works for me; Johannes?
> 
> Seems reasonable, and the patch looks good to me.
> 
> Acked-by: Johannes Weiner <hannes@cmpxchg.org>

Thanks!