From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: [PATCH] clocksource=tsc
Date: Tue, 15 Jul 2008 14:05:14 +0100
Message-ID: <C4A25F1A.23FE1%keir.fraser@eu.citrix.com>
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Cc: Dave Winchell <dwinchell@virtualiron.com>
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On 14/7/08 18:59, "Dan Magenheimer" <dan.magenheimer@oracle.com> wrote:

>> I'm sympathetic to the patch, but it looks like an ugly hack
>> right now.
> 
>> Since it should clearly only affect behaviour when the new
>> clocksource is explicitly selected...
> 
> Actually the ugliness is because the read_counter function
> and plt_mask are both u32 and I worried that changing them to
> a u64 would be too invasive.
> 
> So here's two possible replacement patches, one with those
> switched to u64 and the other with separate 32- and 64-bit
> read_counter functions.  Both are boot-tested with and
> without clocksource=tsc.

Changeset 18055 is what I had in mind. I split out the
read_counter-is-64-bit portion separately. The changeset needs a bit of
testing and it may need a tweak or two.

 -- Keir