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Subject: Re: [PATCH v2] Add suspend/resume for HPET
From: Daniel Walker <dwalker@mvista.com>
To: Ingo Molnar <mingo@elte.hu>
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Date: Sat, 31 Mar 2007 10:58:29 -0700
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On Sat, 2007-03-31 at 19:17 +0200, Ingo Molnar wrote:

> yeah. There's some practical problems that need to be sorted out: much 
> of the current GTOD code is irq-driven (and all GTOD locks are 
> irq-safe), while the sysfs code needs to run in process-context level. 
> 
> Clocksources 'arrive' and 'depart' in hardirq context (which is the 
> primary place where we notice their breakage, determine that they are 
> now verified to be usable, etc.). This came partly from legacy: the 
> gradual conversion of the monolithic time code, and the need to preserve 
> GTOD and non-GTOD architectures without too much duplication. It also 
> came partly because there's also a fundamental need to have accurate 
> time, which is better served from irq context.
> 

Is this in reference to the irq-context clocksource polling stuff? I
don't see a dire reason to keep that code, and I agree removing that is
a certainly a worth while cleanup .. I added this cleanup to one of my
trees when you first suggested it , and there is some infrastructure
that really should be added to facilitate it.

Daniel