From mboxrd@z Thu Jan  1 00:00:00 1970
From: Prarit Bhargava <prarit@redhat.com>
Subject: Re: [patch 3/4] Locally disable the softlockup watchdog rather than
	touching it
Date: Wed, 28 Mar 2007 09:33:52 -0400
Message-ID: <460A6EC0.4020701@redhat.com>
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To: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: virtualization@lists.osdl.org, Andrew Morton <akpm@linux-foundation.org>, Ingo Molnar <mingo@elte.hu>, John Hawkes <hawkes@sgi.com>, Linux Kernel <linux-kernel@vger.kernel.org>, Eric Dumazet <dada1@cosmosbay.com>
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Jeremy Fitzhardinge wrote:
>
> I haven't really worked out how this should interact with the nmi
> watchdog; touch_nmi_watchdog() still ends up calling
> touch_softlockup_watchdog(), so there's still some redundancy here.
>
>   =


touch_nmi_watchdog is attempting to tickle _all_ CPUs softlockup watchdogs.

Currently, the code is incorrect -- it is calling =

touch_softlockup_watchdog which touches only the current CPU's =

softlockup watchdog.

I don't like the idea of having touch_softlockup_watchdog exported with =

your new code -- we still have two methods of effecting the softlockup =

watchdog and that's confusing and its going to cause serious problems =

down the road.  The nmi watchdog code seems fine with just touching the =

CPU's nmi watchdogs.

Is there a reason that you're pushing the enable/disable?  All the cases =

called out seem to be just fine with calls to either effect that CPU's =

softlockup watchdog or doing all CPU's softlockup watchdogs.  I'm not =

sure I see the benefit of complicating the softlockup watchdog code with =

this ...

I agree with the first patch of this set -- it makes sense.  But beyond =

that I'm not convinced the rest of the code is needed ... IMO.

P.