From: Peter Zijlstra <peterz@infradead.org>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Ingo Molnar <mingo@kernel.org>, Kevin Hilman <khilman@linaro.org>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Thomas Gleixner <tglx@linutronix.de>,
Viresh Kumar <viresh.kumar@linaro.org>
Subject: Re: [PATCH 3/3] nohz: Use IPI implicit full barrier against rq->nr_running r/w
Date: Wed, 14 May 2014 11:09:03 +0200 [thread overview]
Message-ID: <20140514090903.GD30445@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <1400019956-25511-4-git-send-email-fweisbec@gmail.com>
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On Wed, May 14, 2014 at 12:25:56AM +0200, Frederic Weisbecker wrote:
> @@ -670,10 +670,11 @@ bool sched_can_stop_tick(void)
>
> rq = this_rq();
>
> - /* Make sure rq->nr_running update is visible after the IPI */
> - smp_rmb();
> -
> - /* More than one running task need preemption */
> + /*
> + * More than one running task need preemption.
> + * nr_running update is assumed to be visible
> + * after IPI is sent from wakers.
> + */
> if (rq->nr_running > 1)
> return false;
Looks like whitespace damage on that comment's indenting.
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next prev parent reply other threads:[~2014-05-14 9:09 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-13 22:25 [PATCH 0/3] nohz: Move nohz kick out of scheduler IPI, v5 Frederic Weisbecker
2014-05-13 22:25 ` [PATCH 1/3] irq_work: Implement remote queueing Frederic Weisbecker
2014-05-14 9:06 ` Peter Zijlstra
2014-05-14 9:10 ` Peter Zijlstra
2014-05-14 11:38 ` Frederic Weisbecker
2014-05-14 11:54 ` Peter Zijlstra
2014-05-14 12:11 ` Frederic Weisbecker
2014-05-14 12:41 ` Peter Zijlstra
2014-05-14 13:51 ` Frederic Weisbecker
2014-05-14 13:55 ` Peter Zijlstra
2014-05-14 14:28 ` Thomas Gleixner
2014-05-13 22:25 ` [PATCH 2/3] nohz: Move full nohz kick to its own IPI Frederic Weisbecker
2014-05-13 22:25 ` [PATCH 3/3] nohz: Use IPI implicit full barrier against rq->nr_running r/w Frederic Weisbecker
2014-05-14 9:09 ` Peter Zijlstra [this message]
2014-05-14 11:38 ` Frederic Weisbecker
-- strict thread matches above, loose matches on Subject: below --
2014-03-19 18:28 [RFC PATCH 0/3] nohz: Move nohz kick out of scheduler IPI Frederic Weisbecker
2014-03-19 18:28 ` [PATCH 3/3] nohz: Use IPI implicit full barrier against rq->nr_running r/w Frederic Weisbecker
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