Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753513AbdC2Ii2 (ORCPT ); Wed, 29 Mar 2017 04:38:28 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:57006 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753150AbdC2Ii0 (ORCPT ); Wed, 29 Mar 2017 04:38:26 -0400 Subject: Re: [PATCH 1/5] locking: Introduce range reader/writer lock To: "Kirill A. Shutemov" , Davidlohr Bueso References: <1488863010-13028-1-git-send-email-dave@stgolabs.net> <1488863010-13028-2-git-send-email-dave@stgolabs.net> <2f7628f4-58e1-22c4-ccbe-3106c15cb405@linux.vnet.ibm.com> <20170328163918.GA27446@linux-80c1.suse> <20170328165803.podjvgo5zim44gip@node.shutemov.name> Cc: mingo@kernel.org, peterz@infradead.org, akpm@linux-foundation.org, jack@suse.cz, kirill.shutemov@linux.intel.com, mhocko@suse.com, mgorman@techsingularity.net, linux-kernel@vger.kernel.org, Davidlohr Bueso From: Laurent Dufour Date: Wed, 29 Mar 2017 10:38:10 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.0 MIME-Version: 1.0 In-Reply-To: <20170328165803.podjvgo5zim44gip@node.shutemov.name> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 17032908-0008-0000-0000-00000412D87B X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17032908-0009-0000-0000-00001D0651F6 Message-Id: <5df9746e-a671-ed3f-89a1-fb6fe6ec4f4e@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-03-29_06:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1702020001 definitions=main-1703290075 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 549 Lines: 11 On 28/03/2017 18:58, Kirill A. Shutemov wrote: > On Tue, Mar 28, 2017 at 09:39:18AM -0700, Davidlohr Bueso wrote: >> I'll wait to see if there are any more concerns and send a v2 with your corrections. > > Have you tried drop-in replacement of mmap_sem with full range lock? > It would be interesting to see performance implication for this. > I've a patch that replace the mmap_sem with a full range lock, it seems to work fine for x86 and ppc64 for now. I'll send it soon. But I didn't yet check for performance. What is the best way to that ?