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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,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 0B968C10F13 for ; Tue, 16 Apr 2019 14:18:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CEB51223EA for ; Tue, 16 Apr 2019 14:18:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="uJcRR0v5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729467AbfDPOSE (ORCPT ); Tue, 16 Apr 2019 10:18:04 -0400 Received: from merlin.infradead.org ([205.233.59.134]:46282 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725796AbfDPOSE (ORCPT ); Tue, 16 Apr 2019 10:18:04 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=lqJk8B1z7WsrVbN/AIY5pxzP/xd/p69LBwimCXdctj4=; b=uJcRR0v5GLXsxy1ONeAX6yWQY CLJIRtdmuzytkV6NyDnJAmZjquKL5vNPaqZ/HpbpnFRF75I5lME1noEimr6zivLY6HJDZa11KUOrI lyiv00u/v7Knu7K6kNWjbd0/0yg3QuhN6PQze1xRO9l2Gt4pX3on8I0Vrfof4q7gjJP6QddSX9AIp pYWtivIjiqCemHKzNY8Ne1iaLnelSHIxNeojk9lSDMFwsZMM+K6AgG5IzSSZzsDrxz/4viEaJq/l3 bhSJp0BXMw3IuDoeuV4Jpo1hc6X/21Ih0NRXsitG3gZ6f6Pj5GG1LpEwfnuIv3hw6DlPWn1XBgr6W rtRQJM/MA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1hGOuE-0003Bs-11; Tue, 16 Apr 2019 14:17:50 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 7B33D28B8C290; Tue, 16 Apr 2019 16:17:47 +0200 (CEST) Date: Tue, 16 Apr 2019 16:17:47 +0200 From: Peter Zijlstra To: Waiman Long Cc: Ingo Molnar , Will Deacon , Thomas Gleixner , linux-kernel@vger.kernel.org, x86@kernel.org, Davidlohr Bueso , Linus Torvalds , Tim Chen , huang ying Subject: Re: [PATCH-tip 0/2] locking/rwsem: Rwsem rearchitecture part 2 follow-up patches Message-ID: <20190416141747.GN4038@hirez.programming.kicks-ass.net> References: <20190415205829.32707-1-longman@redhat.com> <20190416131047.GW11158@hirez.programming.kicks-ass.net> <4747d10b-e9a4-f453-ab4e-13fc984a4067@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4747d10b-e9a4-f453-ab4e-13fc984a4067@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 16, 2019 at 09:18:50AM -0400, Waiman Long wrote: > On 04/16/2019 09:10 AM, Peter Zijlstra wrote: > > On Mon, Apr 15, 2019 at 04:58:27PM -0400, Waiman Long wrote: > >> This series contain 2 follow-up patches to alleviate the performance > >> regression found in the page_fault1 test of the will-it-scale benchmark. > >> This does not recover all the lost performance, but reclaim a sizeable > >> portion of it. > >> > >> The regression was found on an Intel system. I have run the test on > >> an AMD system. The regression wasn't seen there. There are only minor > >> variations in performance. Perhaps the page fault path is quite different > >> between Intel and AMD systems. > > Can you please just fold this back into the appropriate patches? Trying > > to review all the back and forth is painful. > > I will send out an update part 2 patch with patch 1 of this series > merged into the writer spinning on reader patch. Patch 2 of this series > will be a standalone one. Hmm, in that case I can fold it back too. So hold off on sending it. I thought #2 was a fixup for an earlier patch as well.