From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 30 Jan 2008 16:18:02 -0600 From: Robin Holt Subject: Re: [patch 2/6] mmu_notifier: Callbacks to invalidate address ranges Message-ID: <20080130221801.GW26420@sgi.com> References: <20080129211759.GV7233@v2.random> <20080129220212.GX7233@v2.random> <20080130000039.GA7233@v2.random> <20080130161123.GS26420@sgi.com> <20080130170451.GP7233@v2.random> <20080130173009.GT26420@sgi.com> <20080130182506.GQ7233@v2.random> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: Andrea Arcangeli , Robin Holt , Avi Kivity , Izik Eidus , Nick Piggin , kvm-devel@lists.sourceforge.net, Benjamin Herrenschmidt , Peter Zijlstra , steiner@sgi.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, daniel.blueman@quadrics.com, Hugh Dickins List-ID: On Wed, Jan 30, 2008 at 11:50:26AM -0800, Christoph Lameter wrote: > On Wed, 30 Jan 2008, Andrea Arcangeli wrote: > > > XPMEM requires with invalidate_range (sleepy) + > > before_invalidate_range (sleepy). invalidate_all should also be called > > before_release (both sleepy). > > > > It sounds we need full overlap of information provided by > > invalidate_page and invalidate_range to fit all three models (the > > opposite of the zero objective that current V3 is taking). And the > > swap will be handled only by invalidate_page either through linux rmap > > or external rmap (with the latter that can sleep so it's ok for you, > > the former not). GRU can safely use the either the linux rmap notifier > > or the external rmap notifier equally well, because when try_to_unmap > > is called the page is locked and obviously pinned by the VM itself. > > So put the invalidate_page() callbacks in everywhere. The way I am envisioning it, we essentially drop back to Andrea's original patch. We then introduce a invalidate_range_begin (I was really thinking of it as invalidate_and_lock_range()) and an invalidate_range_end (again I was thinking of unlock_range). Thanks, Robin -- 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