From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752676AbbG0JOi (ORCPT ); Mon, 27 Jul 2015 05:14:38 -0400 Received: from casper.infradead.org ([85.118.1.10]:37998 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751071AbbG0JOh (ORCPT ); Mon, 27 Jul 2015 05:14:37 -0400 Date: Mon, 27 Jul 2015 11:14:30 +0200 From: Peter Zijlstra To: Will Deacon Cc: linux-arch@vger.kernel.org, Waiman.Long@hp.com, linux-kernel@vger.kernel.org, paulmck@linux.vnet.ibm.com Subject: Re: [PATCH v3 1/8] atomics: add acquire/release/relaxed variants of some atomic operations Message-ID: <20150727091430.GP19282@twins.programming.kicks-ass.net> References: <1437746681-2809-1-git-send-email-will.deacon@arm.com> <1437746681-2809-2-git-send-email-will.deacon@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1437746681-2809-2-git-send-email-will.deacon@arm.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 24, 2015 at 03:04:34PM +0100, Will Deacon wrote: > This patch introduces three new ordering semantics for these operations: > > - *_relaxed: No ordering guarantees. This is similar to what we have > already for the non-return atomics (e.g. atomic_add). > > - *_acquire: ACQUIRE semantics, similar to smp_load_acquire. > > - *_release: RELEASE semantics, similar to smp_store_release. Do we want to further specify that for the RmW operations the Read/load will provide the acquire and the Write/store the release?