From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olaf Hering Subject: Re: [PATCH 2 of 5] Improve ring management for memory events. Do not lose guest events Date: Mon, 5 Dec 2011 12:23:59 +0100 Message-ID: <20111205112358.GB28908@aepfle.de> References: <43dc614d543cdf84189d.1322603711@xdev.gridcentric.ca> <20111201145103.GA13045@aepfle.de> <457bf805a9709501746d2073fcd9082d.squirrel@webmail.lagarcavilla.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <457bf805a9709501746d2073fcd9082d.squirrel@webmail.lagarcavilla.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Andres Lagar-Cavilla Cc: xen-devel@lists.xensource.com, ian.campbell@citrix.com, andres@gridcentric.ca, tim@xen.org, keir.xen@gmail.com, jbeulich@suse.com, ian.jackson@citrix.com, adin@gridcentric.ca List-Id: xen-devel@lists.xenproject.org On Thu, Dec 01, Andres Lagar-Cavilla wrote: > MAX_HVM_VCPUS sits at 128 right now. Haven't compile checked, but that > probably means we would need a two page ring. And then, when 1024-cpu > hosts arrive and we grow MAX_HVM_VCPUS, we grow the ring size again. The ring has 64 entries. > Or, we could limit the constraint to the number of online vcpus, which > would get somewhat tricky for vcpu hot-plugging. > > I can fix that separately, once there is a decision on which way to go re > ring management. I just sent "[PATCH] mem_event: use wait queue when ring is full" to the list. This version ought to work, it takes the request from both target and foreign cpus into account and leaves at lease one slot for the target. Olaf