From: Chris Snook <csnook@redhat.com>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeff Hansen <x@jeffhansen.com>,
torvalds@linux-foundation.org, linux-kernel@vger.kernel.org,
mingo@elte.hu
Subject: Re: [PATCH] Re: x86_32 tsc/pit and hrtimers
Date: Thu, 09 Oct 2008 14:39:00 -0400 [thread overview]
Message-ID: <48EE4FC4.7070902@redhat.com> (raw)
In-Reply-To: <alpine.LFD.2.00.0810090910510.3237@apollo>
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
next prev parent reply other threads:[~2008-10-09 18:40 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-10-07 22:41 x86_32 tsc/pit and hrtimers Jeff Hansen
2008-10-08 18:41 ` Chris Snook
2008-10-08 19:46 ` Jeff Hansen
2008-10-08 20:25 ` Chris Snook
2008-10-08 21:43 ` [PATCH] " Jeff Hansen
2008-10-08 21:47 ` Randy.Dunlap
2008-10-08 21:47 ` Chris Snook
2008-10-08 21:56 ` Jeff Hansen
2008-10-09 7:14 ` Thomas Gleixner
2008-10-09 18:39 ` Chris Snook [this message]
2008-10-09 19:18 ` Thomas Gleixner
2008-10-09 19:45 ` Jeff Hansen
2008-10-09 19:53 ` Thomas Gleixner
2008-10-09 20:45 ` Alok kataria
2008-10-09 21:03 ` Chris Snook
2008-10-09 21:18 ` Jeff Hansen
2008-10-09 22:03 ` Alok Kataria
2008-10-09 21:53 ` Alok Kataria
2008-10-09 22:50 ` Chris Snook
2008-10-09 23:22 ` Alok Kataria
2008-10-09 23:37 ` Chris Snook
2008-10-10 14:24 ` Jeff Hansen
2008-10-09 17:20 ` Pavel Machek
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