From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id 6DBE46B0083 for ; Sun, 8 Nov 2009 08:05:29 -0500 (EST) Date: Sun, 8 Nov 2009 14:05:21 +0100 From: Ingo Molnar Subject: Re: [PATCH 02/11] Add "handle page fault" PV helper. Message-ID: <20091108130521.GA29728@elte.hu> References: <20091102092214.GB8933@elte.hu> <20091102160410.GF27911@redhat.com> <20091102161248.GB15423@elte.hu> <20091102162234.GH27911@redhat.com> <20091102162941.GC14544@elte.hu> <20091102174208.GJ27911@redhat.com> <20091108113654.GO11372@elte.hu> <4AF6BCE5.3030701@redhat.com> <20091108125135.GA13099@elte.hu> <4AF6C112.4010601@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4AF6C112.4010601@redhat.com> Sender: owner-linux-mm@kvack.org To: Avi Kivity Cc: Gleb Natapov , kvm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, "H. Peter Anvin" , Thomas Gleixner , Fr??d??ric Weisbecker List-ID: * Avi Kivity wrote: > On 11/08/2009 02:51 PM, Ingo Molnar wrote: > >>Maybe we should generalize paravirt-ops patching in case if (x) f() is > >>deemed too expensive. > >Yes, that's a nice idea. We have quite a number of 'conditional > >callbacks' in various critical paths that could be made lighter via such > >a technique. > > > > It would also free new callbacks from the 'it increases overhead > > even if unused' criticism and made it easier to add them. > > We can take the "immediate values" infrastructure as a first step. Has > that been merged? No, there were doubts about whether patching in live instructions like that is safe on all CPU types. Ingo -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org