From mboxrd@z Thu Jan 1 00:00:00 1970 From: Carsten Otte Subject: Re: swapping with MMU Notifiers V2 Date: Tue, 29 Jan 2008 18:17:06 +0100 Message-ID: <479F5F92.5040401@de.ibm.com> References: <20080129145021.GJ7233@v2.random> <479F50D6.4020005@de.ibm.com> <20080129164954.GM7233@v2.random> Reply-To: carsteno-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: carsteno-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org, kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Andrea Arcangeli Return-path: In-Reply-To: <20080129164954.GM7233-lysg2Xt5kKMAvxtiuMwx3w@public.gmane.org> 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 Andrea Arcangeli wrote: > Didn't realize s390 doesn't need those at all. Do you think > mmu_notifier.h should also go in asm/mmu_notifier? We can always move > them there later after merging with some compat code if needed. No I think mmu_notifier.h is fine in include/linux. I just think kvm should only _use_ it on archs that do require assistence. On s390, we use the same page table to translate host.user -> host.phys and guest.phys -> host.phys. Using storage keys, the host memory management takes into account dirty and reference operations done by the guest when doing it's swapping descitions. The host does invalidate a page table entry by using a magic "invalidate page table entry" instruction. Running virtual cpus are guaranteed not to rely on tlb data once the page table entry was invalidated by that instruction. Maybe we should just fix other hardware ;-). ------------------------------------------------------------------------- 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/