From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt1-f198.google.com (mail-qt1-f198.google.com [209.85.160.198]) by kanga.kvack.org (Postfix) with ESMTP id B89578E00B7 for ; Thu, 24 Jan 2019 21:49:48 -0500 (EST) Received: by mail-qt1-f198.google.com with SMTP id 41so9037592qto.17 for ; Thu, 24 Jan 2019 18:49:48 -0800 (PST) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id w81si4865561qkb.30.2019.01.24.18.49.47 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 24 Jan 2019 18:49:47 -0800 (PST) Date: Fri, 25 Jan 2019 10:49:36 +0800 From: Peter Xu Subject: Re: [PATCH RFC 04/24] mm: gup: allow VM_FAULT_RETRY for multiple times Message-ID: <20190125024936.GO18231@xz-x1> References: <20190121075722.7945-1-peterx@redhat.com> <20190121075722.7945-5-peterx@redhat.com> <20190121162455.GC3711@redhat.com> <20190124070503.GJ18231@xz-x1> <20190124153431.GB5030@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190124153431.GB5030@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Jerome Glisse Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Hugh Dickins , Maya Gokhale , Johannes Weiner , Martin Cracauer , Denis Plotnikov , Shaohua Li , Andrea Arcangeli , Mike Kravetz , Marty McFadden , Mike Rapoport , Mel Gorman , "Kirill A . Shutemov" , "Dr . David Alan Gilbert" On Thu, Jan 24, 2019 at 10:34:32AM -0500, Jerome Glisse wrote: > On Thu, Jan 24, 2019 at 03:05:03PM +0800, Peter Xu wrote: > > On Mon, Jan 21, 2019 at 11:24:55AM -0500, Jerome Glisse wrote: > > > On Mon, Jan 21, 2019 at 03:57:02PM +0800, Peter Xu wrote: > > > > This is the gup counterpart of the change that allows the VM_FAULT_RETRY > > > > to happen for more than once. > > > > > > > > Signed-off-by: Peter Xu > > > > > > So it would be nice to add a comment in the code and in the commit message > > > about possible fault starvation (mostly due to previous patch changes) as > > > if some one experience that and try to bisect it might overlook the commit. > > > > > > Otherwise: > > > > > > Reviewed-by: Jérôme Glisse > > > > Jerome, can I still keep this r-b if I'm going to fix the starvation > > issue you mentioned in previous patch about lock page? > > > > No please, i still want to review properly the oneline ie making sure > that it will not change any of the existing use of FAULT_FLAG_TRIED > I am finishing a bunch of patches myself so i am bit short on time right > now to take a deeper look but i will try to do that in next few days :) > > In anycase i will review again your next posting. Sure thing. Thank you Jerome! -- Peter Xu