From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7BF46C43219 for ; Fri, 3 May 2019 05:17:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4AFE62075E for ; Fri, 3 May 2019 05:17:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726298AbfECFRX (ORCPT ); Fri, 3 May 2019 01:17:23 -0400 Received: from mail106.syd.optusnet.com.au ([211.29.132.42]:40834 "EHLO mail106.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726220AbfECFRX (ORCPT ); Fri, 3 May 2019 01:17:23 -0400 Received: from dread.disaster.area (pa49-181-171-240.pa.nsw.optusnet.com.au [49.181.171.240]) by mail106.syd.optusnet.com.au (Postfix) with ESMTPS id C38023DBEE7; Fri, 3 May 2019 15:17:20 +1000 (AEST) Received: from dave by dread.disaster.area with local (Exim 4.92) (envelope-from ) id 1hMQZS-0007iC-Mh; Fri, 03 May 2019 15:17:18 +1000 Date: Fri, 3 May 2019 15:17:18 +1000 From: Dave Chinner To: Davidlohr Bueso Cc: Jan Kara , Amir Goldstein , "Darrick J . Wong" , Christoph Hellwig , Matthew Wilcox , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [POC][PATCH] xfs: reduce ilock contention on buffered randrw workload Message-ID: <20190503051718.GM29573@dread.disaster.area> References: <20190404165737.30889-1-amir73il@gmail.com> <20190404211730.GD26298@dastard> <20190408103303.GA18239@quack2.suse.cz> <1554741429.3326.43.camel@suse.com> <20190411011117.GC29573@dread.disaster.area> <20190416122240.GN29573@dread.disaster.area> <20190418031013.GX29573@dread.disaster.area> <1555611694.18313.12.camel@suse.com> <20190420235412.GY29573@dread.disaster.area> <20190503041727.GL29573@dread.disaster.area> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190503041727.GL29573@dread.disaster.area> User-Agent: Mutt/1.10.1 (2018-07-13) X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.2 cv=FNpr/6gs c=1 sm=1 tr=0 cx=a_idp_d a=LhzQONXuMOhFZtk4TmSJIw==:117 a=LhzQONXuMOhFZtk4TmSJIw==:17 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=kj9zAlcOel0A:10 a=E5NmQfObTbMA:10 a=7-415B0cAAAA:8 a=_g67QGjv7U8_NgNo6WAA:9 a=CjuIK1q_8ugA:10 a=biEYGPWJfzWAr4FL6Ov7:22 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri, May 03, 2019 at 02:17:27PM +1000, Dave Chinner wrote: > Concept proven. > > Next steps are: .... > - work out whether RCU read locking and kfree_rcu() will > work with the requirement to do memory allocation while > holding rcu_read_lock(). Alternative is an internal > garbage collector mechanism, kinda like I've hacked up to > simulate kfree_rcu() in userspace. Internal RCU interactions are now solved. Actually very simple in the end, should be very easy to integrate into the code. Cheers, Dave. -- Dave Chinner david@fromorbit.com