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Date: Tue, 28 Feb 2017 19:56:44 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: =?ISO-8859-15?Q?Andreas_F=E4rber?= <afaerber@suse.de>
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Subject: Re: [PATCH v3 04/25] clocksource: Add Owl timer
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On Tue, 28 Feb 2017, Andreas Färber wrote:
> This is a callback, which I thought is re-entrant.

It's not reentrant at least not on the same CPU. On a SMP machine this
function might be called concurrently on several cores (assumed that the
whole thing is replicated across cores).

> VAL changes when the timer is running, and CTL changes every time we
> enable the timer. We could call _reset() here, but then we would be
> initializing CMP twice, which again would be less performant then just
> setting the registers to their final values directly.

Makes sense.

Thanks,

	tglx
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