linux-kernel - Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work with timers

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Message-ID: <20151208133036.GB3692@ubuntu>
Date:	Tue, 8 Dec 2015 19:00:36 +0530
From:	Viresh Kumar <viresh.kumar@...aro.org>
To:	"Rafael J. Wysocki" <rjw@...ysocki.net>
Cc:	linaro-kernel@...ts.linaro.org, linux-pm@...r.kernel.org,
	ashwin.chaugule@...aro.org,
	"Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
	open list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work
 with timers

On 08-12-15, 14:18, Rafael J. Wysocki wrote:
> Well, if the timer function runs on all CPUs at the same time, they all
> can see skip_work > 1 and none of them will queue the work.

You are talking about code after my patch, right?

Will will all of them see it > 1? At least one of them will see it 0
and queue the work, unless the governor is stopped completely.

> You are right, I've overlooked that race (but then it is rather easy to
> overlook).

Yeah, we (at least I) took a long time to understand that this was the
real problem we always had and so fixed it recently.

-- 
viresh
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