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 47CD7C10F13 for ; Tue, 16 Apr 2019 16:17:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0ADCB20868 for ; Tue, 16 Apr 2019 16:17:35 +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="tcrTrP0P" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729955AbfDPQRd (ORCPT ); Tue, 16 Apr 2019 12:17:33 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:38726 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726605AbfDPQRd (ORCPT ); Tue, 16 Apr 2019 12:17:33 -0400 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=puOlvjKB3Y3WOVRPAmxyhbtthgJ+YL5qig7OLr+ohsc=; b=tcrTrP0P0B/fwDtHvJAtUjuQP IO9VA4Azju/qglP18WD9SwkBmbD56neNBCy7nemOs44hiCj81O+s6FlR14weA4/b+q58MK7gvlWHB cZ/ivhWMNJtye5FWk69DI6vOwfGga76FH+xNZ9WVtk2VzY2kESG4yCcRpjZzIYLsxZr4ZFt7q143K RML9YT4FAOGRUZbEOrsIPdm4dqRlo4zpS5LDOr7Q+cEI0u8sq4MDXvQa/jcYakFUr2IkAUjczkR4f 2A1HLWsv/aoe7/YA062css1+8A4RpzgT0hWVufG5AObkOEzpMmC3Yrpzy/W8X0lAO3/xSbVCmqZTe O84Epel1A==; 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 1hGQm0-0003q2-LD; Tue, 16 Apr 2019 16:17:28 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 2776129AC1641; Tue, 16 Apr 2019 18:17:27 +0200 (CEST) Date: Tue, 16 Apr 2019 18:17:27 +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 v4 06/16] locking/rwsem: Code cleanup after files merging Message-ID: <20190416161727.GS14281@hirez.programming.kicks-ass.net> References: <20190413172259.2740-1-longman@redhat.com> <20190413172259.2740-7-longman@redhat.com> <20190416160113.GM12232@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190416160113.GM12232@hirez.programming.kicks-ass.net> 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 06:01:13PM +0200, Peter Zijlstra wrote: > @@ -794,34 +770,38 @@ static inline int __down_read_trylock(st > */ > static inline void __down_write(struct rw_semaphore *sem) > { > - if (unlikely(atomic_long_cmpxchg_acquire(&sem->count, 0, > - RWSEM_WRITER_LOCKED))) > - rwsem_down_write_failed(sem); > + long tmp = RWSEM_UNLOCKED_VALUE; > + > + if (unlikely(atomic_long_try_cmpxchg_acquire(&sem->count, &tmp, > + RWSEM_WRITER_LOCKED))) ! > + rwsem_down_write_slow(sem, TASK_UNINTERRUPTIBLE); > rwsem_set_owner(sem); > } > > static inline int __down_write_killable(struct rw_semaphore *sem) > { > - if (unlikely(atomic_long_cmpxchg_acquire(&sem->count, 0, > - RWSEM_WRITER_LOCKED))) > - if (IS_ERR(rwsem_down_write_failed_killable(sem))) > + long tmp = RWSEM_UNLOCKED_VALUE; > + > + if (unlikely(atomic_long_try_cmpxchg_acquire(&sem->count, &tmp, > + RWSEM_WRITER_LOCKED))) { also ! > + if (IS_ERR(rwsem_down_write_slow(sem, TASK_KILLABLE))) > return -EINTR; > + } > rwsem_set_owner(sem); > return 0; > } I'm having a great day it seems, it's like back in uni, trying to find all the missing - signs in this page-long DE.