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Subject: Re: [PATCH] msleep() with hrtimers
From: Arjan van de Ven <arjan@infradead.org>
To: Roman Zippel <zippel@linux-m68k.org>
Cc: Jonathan Corbet <corbet@lwn.net>, linux-kernel@vger.kernel.org,
       Thomas Gleixner <tglx@linutronix.de>, akpm@linux-foundation.org,
       Ingo Molnar <mingo@elte.hu>
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Organization: Intel International BV
Date: Fri, 03 Aug 2007 12:46:46 -0700
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On Fri, 2007-08-03 at 21:19 +0200, Roman Zippel wrote:
> Hi,
> 
> On Fri, 3 Aug 2007, Jonathan Corbet wrote:
> 
> > Most comments last time were favorable.  The one dissenter was Roman,
> > who worries about the overhead of using hrtimers for this operation; my
> > understanding is that he would rather see a really_msleep() function for
> > those who actually want millisecond resolution.  I'm not sure how to
> > characterize what the cost could be, but it can only be buried by the
> > fact that every call sleeps for some number of milliseconds.  On my
> > system, the several hundred total msleep() calls can't cause any real
> > overhead, and almost all happen at initialization time.
> 
> The main point is still that these are two _different_ APIs for different 
> usages, so I still prefer to add a hrsleep() instead.


I would actually prefer it the other way around; call the
not-so-accurate one "msleep_approx()" or somesuch, to make it explicit
that the sleep is only approximate...