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Date: Tue, 2 Feb 2016 15:02:07 +0530
From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>,
        Matt Fleming <matt@codeblueprint.co.uk>,
        Mike Galbraith <mgalbraith@suse.de>,
        LKML <linux-kernel@vger.kernel.org>,
        "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
Subject: Re: [PATCH 1/1] sched: Make schedstats a runtime tunable that is
 disabled by default v3
Message-ID: <20160202093207.GA9494@linux.vnet.ibm.com>
Reply-To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
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Dont we need changes for sched_info_on()?

If we disable schedstats dynamically but CONFIG_TASK_DELAY_ACCT is not
set, then sched_info_on will return true, This could impact guest steal
time stats as well as data read from /proc/<PID>/schedstat

Also when schedstats is dynamically disabled, and user tries to enable
kernel sleep profiling profile_setup(), the kernel may not be able to do
the right profiling since enqueue_sleeper() may not get called. Should
we alert the user saying kernel sleep profiling is disabled?

-- 
Thanks and Regards
Srikar Dronamraju