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Date:   Mon, 9 Jul 2018 12:47:59 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     xunlei <xunlei.pang@gmail.com>
Cc:     Xunlei Pang <xlpang@linux.alibaba.com>,
        Ingo Molnar <mingo@redhat.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        Tejun Heo <tj@kernel.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sched/cputime: Ensure correct utime and stime proportion
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On Thu, Jul 05, 2018 at 09:58:50PM +0800, xunlei wrote:
> It is rtime < utime + stime, that is the imprecise tick-based run time
> may be larger than precise sum_exec_runtime scheduler-based run time, it
> can happen with some frequent run-sleep patterns.

You're still comparing two values that should not be compared. utime +
stime is not a run-time. You _CANNOT_ compare to rtime and doing so
means you're still not getting it.