From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Holt Subject: Re: [patch 2/6] mmu_notifier: Callbacks to invalidate address ranges Date: Wed, 30 Jan 2008 20:34:01 -0600 Message-ID: <20080131023401.GY26420@sgi.com> References: <20080130000039.GA7233@v2.random> <20080130161123.GS26420@sgi.com> <20080130170451.GP7233@v2.random> <20080130173009.GT26420@sgi.com> <20080130182506.GQ7233@v2.random> <20080130235214.GC7185@v2.random> <20080131003434.GE7185@v2.random> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Nick Piggin , Andrea Arcangeli , Peter Zijlstra , kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Benjamin Herrenschmidt , steiner-sJ/iWh9BUns@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Avi Kivity , linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, daniel.blueman-xqY44rlHlBpWk0Htik3J/w@public.gmane.org, Robin Holt , Hugh Dickins To: Christoph Lameter Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org > Well the GRU uses follow_page() instead of get_user_pages. Performance is > a major issue for the GRU. Worse, the GRU takes its TLB faults from within an interrupt so we use follow_page to prevent going to sleep. That said, I think we could probably use follow_page() with FOLL_GET set to accomplish the requirements of mmu_notifier invalidate_range call. Doesn't look too promising for hugetlb pages. Thanks, Robin ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/