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=-5.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, USER_AGENT_MUTT autolearn=unavailable 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 E4503C43381 for ; Thu, 14 Feb 2019 11:12:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B43912229F for ; Thu, 14 Feb 2019 11:12:30 +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="aXK6FgEj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389705AbfBNLMZ (ORCPT ); Thu, 14 Feb 2019 06:12:25 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:34400 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728131AbfBNLMZ (ORCPT ); Thu, 14 Feb 2019 06:12:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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=RGD/5MGOpZ+sFP4R8UzfseaMWuC+CODQr7wgC7RV1xU=; b=aXK6FgEjxQe4HE+pqXtNxte1s e1KXKHwIkueTFj7AL/+JldbMVhvx6dLSMCbckz6qEQUZ2Xj4sNYSt/Xc8mMP4ae/GvMWNheET4lEq WpByu3FunDFSksawPP1YKZz06spM0alNJGxCZtwoAcAaCTS1QPF/mH7XwCJpC3IgoyV/ZiJ/JWLLm nldVSTsoIlsYCW3voFKdiu5idA2iMfnY6BnYzmHNbqkTqiCiEB9L0C4xt2WS+UrXFNU5M8XgqWkrV MBhZ30zYcnlsc9GwO9Yoh3BbSE51bib0igHJ3kupqom97wzlqhnDWWtj5QruePCversvPk04l1mYH Qw8efa4qw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1guEw9-0001pc-2H; Thu, 14 Feb 2019 11:12:13 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 7B5AD20298565; Thu, 14 Feb 2019 12:12:11 +0100 (CET) Date: Thu, 14 Feb 2019 12:12:11 +0100 From: Peter Zijlstra To: Geert Uytterhoeven Cc: Waiman Long , Christoph Hellwig , Ingo Molnar , Will Deacon , Thomas Gleixner , "linux-ia64@vger.kernel.org" , Linux-sh list , linux-mips@vger.kernel.org, "H. Peter Anvin" , sparclinux , linux-riscv@lists.infradead.org, Linux-Arch , linux-s390 , Davidlohr Bueso , linux-c6x-dev@linux-c6x.org, "open list:QUALCOMM HEXAGON..." , the arch/x86 maintainers , "moderated list:H8/300 ARCHITECTURE" , linux-xtensa@linux-xtensa.org, Arnd Bergmann , linux-um@lists.infradead.org, linux-m68k , Openrisc , Borislav Petkov , Linux ARM , Tim Chen , Parisc List , Linus Torvalds , Linux Kernel Mailing List , alpha , nios2-dev@lists.rocketboards.org, Andrew Morton , linuxppc-dev Subject: Re: [PATCH v4 2/3] locking/rwsem: Remove rwsem-spinlock.c & use rwsem-xadd.c for all archs Message-ID: <20190214111211.GL32494@hirez.programming.kicks-ass.net> References: <1550095217-12047-1-git-send-email-longman@redhat.com> <1550095217-12047-3-git-send-email-longman@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On Thu, Feb 14, 2019 at 11:54:47AM +0100, Geert Uytterhoeven wrote: > On Wed, Feb 13, 2019 at 11:01 PM Waiman Long wrote: > > Currently, we have two different implementation of rwsem: > > 1) CONFIG_RWSEM_GENERIC_SPINLOCK (rwsem-spinlock.c) > > 2) CONFIG_RWSEM_XCHGADD_ALGORITHM (rwsem-xadd.c) > > > > As we are going to use a single generic implementation for rwsem-xadd.c > > and no architecture-specific code will be needed, there is no point > > in keeping two different implementations of rwsem. In most cases, the > > performance of rwsem-spinlock.c will be worse. It also doesn't get all > > the performance tuning and optimizations that had been implemented in > > rwsem-xadd.c over the years. > > > > For simplication, we are going to remove rwsem-spinlock.c and make all > > architectures use a single implementation of rwsem - rwsem-xadd.c. > > > > All references to RWSEM_GENERIC_SPINLOCK and RWSEM_XCHGADD_ALGORITHM > > in the code are removed. > > > > Suggested-by: Peter Zijlstra > > Signed-off-by: Waiman Long > > Note that this conflicts with "[PATCH 03/11] kernel/locks: consolidate > RWSEM_GENERIC_* options" > https://lore.kernel.org/lkml/20190213174005.28785-4-hch@lst.de/ *sigh*.. of that never was Cc'ed to locking people :/