From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758095AbYEDWIi (ORCPT ); Sun, 4 May 2008 18:08:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756081AbYEDWIa (ORCPT ); Sun, 4 May 2008 18:08:30 -0400 Received: from host36-195-149-62.serverdedicati.aruba.it ([62.149.195.36]:43187 "EHLO mx.cpushare.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755961AbYEDWIa (ORCPT ); Sun, 4 May 2008 18:08:30 -0400 Date: Mon, 5 May 2008 00:08:25 +0200 From: Andrea Arcangeli To: Robin Holt Cc: Andrew Morton , Christoph Lameter , Jack Steiner , Nick Piggin , Peter Zijlstra , kvm-devel@lists.sourceforge.net, Kanoj Sarcar , Roland Dreier , Steve Wise , linux-kernel@vger.kernel.org, Avi Kivity , linux-mm@kvack.org, general@lists.openfabrics.org, Hugh Dickins , Rusty Russell , Anthony Liguori , Chris Wright , Marcelo Tosatti , Eric Dumazet , "Paul E. McKenney" Subject: Re: [PATCH 01 of 11] mmu-notifier-core Message-ID: <20080504220824.GA21051@duo.random> References: <1489529e7b53d3f2dab8.1209740704@duo.random> <20080504191345.GD18857@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080504191345.GD18857@sgi.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, May 04, 2008 at 02:13:45PM -0500, Robin Holt wrote: > > diff --git a/mm/Kconfig b/mm/Kconfig > > --- a/mm/Kconfig > > +++ b/mm/Kconfig > > @@ -205,3 +205,6 @@ config VIRT_TO_BUS > > config VIRT_TO_BUS > > def_bool y > > depends on !ARCH_NO_VIRT_TO_BUS > > + > > +config MMU_NOTIFIER > > + bool > > Without some text following the bool keyword, I am not even asked for > this config setting on my ia64 build. Yes, this was explicitly asked by Andrew after his review. This is the explanation pasted from the changelog. 3) It'd be a waste to add branches in the VM if nobody could possibly run KVM/GRU/XPMEM on the kernel, so mmu notifiers will only enabled if CONFIG_KVM=m/y. In the current kernel kvm won't yet take advantage of mmu notifiers, but this already allows to compile a KVM external module against a kernel with mmu notifiers enabled and from the next pull from kvm.git we'll start using them. And GRU/XPMEM will also be able to continue the development by enabling KVM=m in their config, until they submit all GRU/XPMEM GPLv2 code to the mainline kernel. Then they can also enable MMU_NOTIFIERS in the same way KVM does it (even if KVM=n). This guarantees nobody selects MMU_NOTIFIER=y if KVM and GRU and XPMEM are all =n. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrea Arcangeli Subject: Re: [PATCH 01 of 11] mmu-notifier-core Date: Mon, 5 May 2008 00:08:25 +0200 Message-ID: <20080504220824.GA21051@duo.random> References: <1489529e7b53d3f2dab8.1209740704@duo.random> <20080504191345.GD18857@sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Nick Piggin , Chris Wright , Steve Wise , Peter Zijlstra , kvm-devel@lists.sourceforge.net, Kanoj Sarcar , Roland Dreier , Jack Steiner , linux-kernel@vger.kernel.org, Avi Kivity , Marcelo Tosatti , "Paul E. McKenney" , linux-mm@kvack.org, general@lists.openfabrics.org, Hugh Dickins , Andrew Morton , Eric Dumazet , Christoph Lameter To: Robin Holt Return-path: Content-Disposition: inline In-Reply-To: <20080504191345.GD18857@sgi.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces@lists.sourceforge.net Errors-To: kvm-devel-bounces@lists.sourceforge.net List-Id: kvm.vger.kernel.org On Sun, May 04, 2008 at 02:13:45PM -0500, Robin Holt wrote: > > diff --git a/mm/Kconfig b/mm/Kconfig > > --- a/mm/Kconfig > > +++ b/mm/Kconfig > > @@ -205,3 +205,6 @@ config VIRT_TO_BUS > > config VIRT_TO_BUS > > def_bool y > > depends on !ARCH_NO_VIRT_TO_BUS > > + > > +config MMU_NOTIFIER > > + bool > > Without some text following the bool keyword, I am not even asked for > this config setting on my ia64 build. Yes, this was explicitly asked by Andrew after his review. This is the explanation pasted from the changelog. 3) It'd be a waste to add branches in the VM if nobody could possibly run KVM/GRU/XPMEM on the kernel, so mmu notifiers will only enabled if CONFIG_KVM=m/y. In the current kernel kvm won't yet take advantage of mmu notifiers, but this already allows to compile a KVM external module against a kernel with mmu notifiers enabled and from the next pull from kvm.git we'll start using them. And GRU/XPMEM will also be able to continue the development by enabling KVM=m in their config, until they submit all GRU/XPMEM GPLv2 code to the mainline kernel. Then they can also enable MMU_NOTIFIERS in the same way KVM does it (even if KVM=n). This guarantees nobody selects MMU_NOTIFIER=y if KVM and GRU and XPMEM are all =n. ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 5 May 2008 00:08:25 +0200 From: Andrea Arcangeli Subject: Re: [PATCH 01 of 11] mmu-notifier-core Message-ID: <20080504220824.GA21051@duo.random> References: <1489529e7b53d3f2dab8.1209740704@duo.random> <20080504191345.GD18857@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080504191345.GD18857@sgi.com> Sender: owner-linux-mm@kvack.org Return-Path: To: Robin Holt Cc: Andrew Morton , Christoph Lameter , Jack Steiner , Nick Piggin , Peter Zijlstra , kvm-devel@lists.sourceforge.net, Kanoj Sarcar , Roland Dreier , Steve Wise , linux-kernel@vger.kernel.org, Avi Kivity , linux-mm@kvack.org, general@lists.openfabrics.org, Hugh Dickins , Rusty Russell , Anthony Liguori , Chris Wright , Marcelo Tosatti , Eric Dumazet , "Paul E. McKenney" List-ID: On Sun, May 04, 2008 at 02:13:45PM -0500, Robin Holt wrote: > > diff --git a/mm/Kconfig b/mm/Kconfig > > --- a/mm/Kconfig > > +++ b/mm/Kconfig > > @@ -205,3 +205,6 @@ config VIRT_TO_BUS > > config VIRT_TO_BUS > > def_bool y > > depends on !ARCH_NO_VIRT_TO_BUS > > + > > +config MMU_NOTIFIER > > + bool > > Without some text following the bool keyword, I am not even asked for > this config setting on my ia64 build. Yes, this was explicitly asked by Andrew after his review. This is the explanation pasted from the changelog. 3) It'd be a waste to add branches in the VM if nobody could possibly run KVM/GRU/XPMEM on the kernel, so mmu notifiers will only enabled if CONFIG_KVM=m/y. In the current kernel kvm won't yet take advantage of mmu notifiers, but this already allows to compile a KVM external module against a kernel with mmu notifiers enabled and from the next pull from kvm.git we'll start using them. And GRU/XPMEM will also be able to continue the development by enabling KVM=m in their config, until they submit all GRU/XPMEM GPLv2 code to the mainline kernel. Then they can also enable MMU_NOTIFIERS in the same way KVM does it (even if KVM=n). This guarantees nobody selects MMU_NOTIFIER=y if KVM and GRU and XPMEM are all =n. -- 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