From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keir Fraser Subject: Re: Need help with fixing the Xen waitqueue feature Date: Tue, 22 Nov 2011 17:42:20 +0000 Message-ID: References: <20111122173618.GA1304@aepfle.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20111122173618.GA1304@aepfle.de> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Olaf Hering Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On 22/11/2011 17:36, "Olaf Hering" wrote: > On Tue, Nov 22, Keir Fraser wrote: > >> I have a new theory, which is that if we go round the for-loop in >> wait_event() more than once, the vcpu's pause counter gets messed up and >> goes negative, condemning it to sleep forever. > > I have added a check for that, its not negative. > >> I have *just* pushed a change to the debug 'q' key (ignore the changeset >> comment referring to 'd' key, I got that wrong!) which will print per-vcpu >> and per-domain pause_count values. Please get the system stuck again, and >> send the output from 'q' key with that new changeset (c/s 24178). > > To me it looks like dom0 gets paused, perhaps due to some uneven pause/unpause > calls. > I will see if I can figure it out. Could it have ended up on the waitqueue? -- Keir