From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrea Arcangeli Subject: [ofa-general] Re: [patch 01/10] emm: mm_lock: Lock a process against reclaim Date: Mon, 7 Apr 2008 21:35:44 +0200 Message-ID: <20080407193544.GH20587@duo.random> References: <20080404223048.374852899@sgi.com> <20080404223131.271668133@sgi.com> <47F6B5EA.6060106@goop.org> <20080405004127.GG14784@duo.random> <47FA6FDD.9060605@goop.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <47FA6FDD.9060605@goop.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: general-bounces@lists.openfabrics.org Errors-To: general-bounces@lists.openfabrics.org To: Jeremy Fitzhardinge Cc: Peter Zijlstra , kvm-devel@lists.sourceforge.net, steiner@sgi.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Robin Holt , general@lists.openfabrics.org, Christoph Lameter List-Id: linux-mm.kvack.org On Mon, Apr 07, 2008 at 12:02:53PM -0700, Jeremy Fitzhardinge wrote: > It's per-mm though. How many processes would need to have notifiers? There can be up to hundreds of VM in a single system. Not sure to understand the point of the question though. > Well, its definitely going to need more comments then. I assumed it would > end up locking everything, so unlocking everything would be sufficient. After your comments, I'm writing an alternate version that will guarantee a O(N) worst case to both sigkill and cond_resched but frankly this is low priority. Without mmu notifiers /dev/kvm can't be given to a normal luser without at least losing mlock ulimits, so lack of a mmu notifiers is a bigger issue than whatever complexity in mm_lock as far as /dev/kvm ownership is concerned.