Subject: Re: [PATCH 22/23] clocksource: new clock lookup method
From: Thomas Gleixner <tglx@linutronix.de>
Reply-To: tglx@linutronix.de
To: Daniel Walker <dwalker@mvista.com>
Cc: Ingo Molnar <mingo@elte.hu>, akpm@osdl.org, linux-kernel@vger.kernel.org,
       johnstul@us.ibm.com
In-Reply-To: <1170265169.9781.145.camel@imap.mvista.com>
References: <20070131033710.420168478@mvista.com>
	 <20070131033809.923199123@mvista.com> <20070131122215.GE1847@elte.hu>
	 <1170261439.9781.96.camel@imap.mvista.com>  <20070131164918.GA4468@elte.hu>
	 <1170265169.9781.145.camel@imap.mvista.com>
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Date: Wed, 31 Jan 2007 18:55:31 +0100
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On Wed, 2007-01-31 at 09:39 -0800, Daniel Walker wrote:
> > please read my reply above! To repeat: such flags tend to get forgotten, 
> > resulting in a less safe default behavior. Clock hardware and thus 
> > clocksources are fundamentally fragile so we want to default to the 
> > safest behavior. I.e. if the IS_CONTINOUS flag is 'forgotten', the clock 
> > wont be usable as a clock verification base for example. The flag has to 
> > be affirmatively set to mark the clocksource continous.
> 
> I don't see this as an issue .. Your assuming that not continuous clocks
> will be prevalent which they aren't ..

And how does this change Ingo's statement ? Such beasts exist and having
them default to the safe side is good. 

Also I really do not see the "huge burden" for a clocksource coder to
add this flag. If he forgets it, then he can not use highres / dynticks
and nothing breaks.

	tglx


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