From mboxrd@z Thu Jan 1 00:00:00 1970 From: Glauber de Oliveira Costa Subject: Re: [PATCH/RFC] Wrong account for cpus other than 0 on hotplug Date: Fri, 13 Oct 2006 18:18:50 -0300 Message-ID: <20061013211850.GA14367@redhat.com> References: <20061013175025.GA13539@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On Fri, Oct 13, 2006 at 09:33:53PM +0100, Keir Fraser wrote: > On 13/10/06 6:50 pm, "Glauber de Oliveira Costa" wrote: > > > This patch turns off the missing ticks accounting entirely, as the > runstate_info structure will never be updated. Are you sure this appears to > be an x86_64-specific issue? That's why I was almost sure it was wrong, and was expecting comments :-) Among all machines we have, it just seem to be happening in a few of them. Besides being x86_64, they're 8-way, which can be another sort of problem. I just found that the offending code is in the HV itself, and not in the guest. In arch_do_vcpu_op(), we see that the information is only passed up to the guest, if the check (current == v) holds, which seems to be the true source of it. (taking the check away makes it work). I can see no reason for this check to be there. If there is one, we could maybe make sure it holds. (maybe calling set_current(v) on HV side?) Your comments on this are , as usual, very welcome ;-) -- Glauber de Oliveira Costa Red Hat Inc. "Free as in Freedom"