From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755290AbaIQLmU (ORCPT ); Wed, 17 Sep 2014 07:42:20 -0400 Received: from mail-wg0-f51.google.com ([74.125.82.51]:35918 "EHLO mail-wg0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754634AbaIQLmT convert rfc822-to-8bit (ORCPT ); Wed, 17 Sep 2014 07:42:19 -0400 Date: Wed, 17 Sep 2014 14:42:15 +0300 From: Gleb Natapov To: Radim =?utf-8?B?S3LEjW3DocWZ?= Cc: Andres Lagar-Cavilla , Gleb Natapov , Rik van Riel , Peter Zijlstra , Mel Gorman , Andy Lutomirski , Andrew Morton , Andrea Arcangeli , Sasha Levin , Jianyu Zhan , Paul Cassella , Hugh Dickins , Peter Feiner , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH] kvm: Faults which trigger IO release the mmap_sem Message-ID: <20140917114214.GB30733@minantech.com> References: <1410811885-17267-1-git-send-email-andreslc@google.com> <20140917102635.GA30733@minantech.com> <20140917112713.GB1273@potion.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8BIT In-Reply-To: <20140917112713.GB1273@potion.brq.redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 17, 2014 at 01:27:14PM +0200, Radim Krčmář wrote: > 2014-09-17 13:26+0300, Gleb Natapov: > > For async_pf_execute() you do not need to even retry. Next guest's page fault > > will retry it for you. > > Wouldn't that be a waste of vmentries? This is how it will work with or without this second gup. Page is not mapped into a shadow page table on this path, it happens on a next fault. -- Gleb. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: [PATCH] kvm: Faults which trigger IO release the mmap_sem Date: Wed, 17 Sep 2014 14:42:15 +0300 Message-ID: <20140917114214.GB30733@minantech.com> References: <1410811885-17267-1-git-send-email-andreslc@google.com> <20140917102635.GA30733@minantech.com> <20140917112713.GB1273@potion.brq.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: Andres Lagar-Cavilla , Gleb Natapov , Rik van Riel , Peter Zijlstra , Mel Gorman , Andy Lutomirski , Andrew Morton , Andrea Arcangeli , Sasha Levin , Jianyu Zhan , Paul Cassella , Hugh Dickins , Peter Feiner , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org To: Radim =?utf-8?B?S3LEjW3DocWZ?= Return-path: Content-Disposition: inline In-Reply-To: <20140917112713.GB1273@potion.brq.redhat.com> Sender: owner-linux-mm@kvack.org List-Id: kvm.vger.kernel.org On Wed, Sep 17, 2014 at 01:27:14PM +0200, Radim Kr=C4=8Dm=C3=A1=C5=99 wrote: > 2014-09-17 13:26+0300, Gleb Natapov: > > For async_pf_execute() you do not need to even retry. Next guest's page= fault > > will retry it for you. >=20 > Wouldn't that be a waste of vmentries? This is how it will work with or without this second gup. Page is not mapped into a shadow page table on this path, it happens on a next fault. -- Gleb. -- 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