From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f70.google.com (mail-wm0-f70.google.com [74.125.82.70]) by kanga.kvack.org (Postfix) with ESMTP id 9AA316B03C1 for ; Thu, 20 Apr 2017 10:39:41 -0400 (EDT) Received: by mail-wm0-f70.google.com with SMTP id z129so2902330wmb.23 for ; Thu, 20 Apr 2017 07:39:41 -0700 (PDT) Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com. [148.163.158.5]) by mx.google.com with ESMTPS id 136si9835415wms.126.2017.04.20.07.39.40 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 20 Apr 2017 07:39:40 -0700 (PDT) Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v3KEd8tL076611 for ; Thu, 20 Apr 2017 10:39:39 -0400 Received: from e06smtp12.uk.ibm.com (e06smtp12.uk.ibm.com [195.75.94.108]) by mx0b-001b2d01.pphosted.com with ESMTP id 29xxf9sscs-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 20 Apr 2017 10:39:38 -0400 Received: from localhost by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 20 Apr 2017 15:39:36 +0100 Subject: Re: [RFC 0/4] Replace mmap_sem by a range lock References: <20170420133338.GC27790@bombadil.infradead.org> From: Laurent Dufour Date: Thu, 20 Apr 2017 16:39:32 +0200 MIME-Version: 1.0 In-Reply-To: <20170420133338.GC27790@bombadil.infradead.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Message-Id: <87628c87-d320-87e7-5076-b26432a72a0f@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: Matthew Wilcox Cc: linux-mm@kvack.org, Davidlohr Bueso , akpm@linux-foundation.org, Jan Kara , "Kirill A . Shutemov" , Michal Hocko , Peter Zijlstra , Mel Gorman , haren@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, khandual@linux.vnet.ibm.com, Paul.McKenney@us.ibm.com, linux-kernel@vger.kernel.org On 20/04/2017 15:33, Matthew Wilcox wrote: > On Wed, Apr 19, 2017 at 02:18:23PM +0200, Laurent Dufour wrote: >> Following the series pushed by Davidlohr Bueso based on the Jan Kara's >> work [1] which introduces range locks, this series implements the >> first step of the attempt to replace the mmap_sem by a range lock. > > Have you previously documented attempts to replace the mmap_sem by an > existing lock type before introducing a new (and frankly weird) lock? No :/ > My initial question is "Why not use RCU for this?" -- the rxrpc code > uses an rbtree protected by RCU. I'm also working on forward-porting work done by Peter Zijlstra : https://marc.info/?l=linux-mm&m=141384492326748 I'll send a series on top 4.10 soon. -- 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