Date: Tue, 14 Feb 2006 08:41:51 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Roman Zippel <zippel@linux-m68k.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, Andrew Morton <akpm@osdl.org>,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH 01/13] hrtimer: round up relative start time
Message-ID: <20060214074151.GA29426@elte.hu>
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ok, lets go back to this one:

* Roman Zippel <zippel@linux-m68k.org> wrote:

> Let's assume a get_time() which simply returns xtime and so has a 
> resolution of around TICK_NSEC. This means the real time when one 
> calls get_time() is somewhere between xtime and xtime+TICK_NSEC.  
> Assuming the real time is xtime+TICK_NSEC-1, get_time() will return 
> xtime and a relative timer with TICK_NSEC-1 will expire immediately.

i agree that on systems where get_time() has a TICK_NSEC resolution, 
such short timeouts are bad.

i dont agree with the fix though: it penalizes platforms where 
->get_time() resolution is sane.

	Ingo
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