Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757535AbcK3Jku (ORCPT ); Wed, 30 Nov 2016 04:40:50 -0500 Received: from mail.fireflyinternet.com ([109.228.58.192]:60598 "EHLO fireflyinternet.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756722AbcK3Jkn (ORCPT ); Wed, 30 Nov 2016 04:40:43 -0500 X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Date: Wed, 30 Nov 2016 09:40:34 +0000 From: Chris Wilson To: Nicolai =?iso-8859-1?Q?H=E4hnle?= Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH 00/11] locking/ww_mutex: Keep sorted wait list to avoid stampedes Message-ID: <20161130094034.GM23336@nuc-i3427.alporthouse.com> References: <1480335612-12069-1-git-send-email-nhaehnle@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1480335612-12069-1-git-send-email-nhaehnle@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 571 Lines: 13 On Mon, Nov 28, 2016 at 01:20:01PM +0100, Nicolai H?hnle wrote: > I've included timings taken from a contention-heavy stress test to some of > the patches. The stress test performs actual GPU operations which take a > good chunk of the wall time, but even so, the series still manages to > improve the wall time quite a bit. In looking at your contention scenarios, what was the average/max list size? Just wondering if it makes sense to use an rbtree + first_waiter instead of a sorted list from the start. -Chris -- Chris Wilson, Intel Open Source Technology Centre