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Date:	Thu, 09 Oct 2008 14:39:00 -0400
From:	Chris Snook <csnook@...hat.com>
To:	Thomas Gleixner <tglx@...utronix.de>
CC:	Jeff Hansen <x@...fhansen.com>, torvalds@...ux-foundation.org,
	linux-kernel@...r.kernel.org, mingo@...e.hu
Subject: Re: [PATCH] Re: x86_32 tsc/pit and hrtimers

Thomas Gleixner wrote:
> On Wed, 8 Oct 2008, Jeff Hansen wrote:
> 
>> [HRTIMER]: Add highres=noverify option to bypass clocksource verification
>>
>> This disregards the CLOCK_SOURCE_MUST_VERIFY flag on all clocksources.
>> This is particularly useful on legacy x86_32 systems that have no ACPI,
>> LAPIC, or HPET timers, where only TSC and PIT are available.
> 
> While I agree in principle, adding this to highres is the wrong thing
> to do. This is a property of clocksources and not of high resolution
> timer support.
> 
> The affected clocksource is TSC and it should go there as a command
> line option e.g. tsc=stable, which in turn clears the
> CLOCK_SOURCE_MUST_VERIFY flag in the tsc clocksource.
> 
> Thanks,
> 
> 	tglx

Fair enough, but do you think it's worthwhile to have an option to 
disable CLOCK_SOURCE_MUST_VERIFY checking for all timers, or should we 
implement this on a case-by-case basis when there's legitimate cause, 
like with TSC?

-- Chris
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