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From: Arnd Bergmann <arnd@arndb.de>
To: Jonathan Corbet <corbet@lwn.net>
Subject: Re: [PATCH/RFC] msleep() with hrtimers
Date: Mon, 16 Jul 2007 01:10:56 +0200
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On Monday 16 July 2007, Jonathan Corbet wrote:
> Here's another approach: a reimplementation of msleep() and
> msleep_interruptible() using hrtimers.  On a system without real
> hrtimers this code will at least drop down to single-jiffy delays much
> of the time (though not deterministically so).  On my x86_64 system with
> Thomas's hrtimer/dyntick patch applied, msleep(1) gives almost exactly
> what was asked for.

This reminds me of a patch I did some time ago, without ever getting
any feedback on it:

http://lkml.org/lkml/2007/3/4/165

In addition to just msleep, it converted all users of schedule_timeout()
as well as sys_*select(). I actually ran with that patch on my
main worstation for a few weeks, and while it did not crash, I
saw some strange behaviour after all.

	Arnd <><