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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=no 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 5DA3AC432C0 for ; Mon, 25 Nov 2019 21:46:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 311BB2071A for ; Mon, 25 Nov 2019 21:46:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725930AbfKYVq1 (ORCPT ); Mon, 25 Nov 2019 16:46:27 -0500 Received: from mail.kernel.org ([198.145.29.99]:34736 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725912AbfKYVq1 (ORCPT ); Mon, 25 Nov 2019 16:46:27 -0500 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9405E20706; Mon, 25 Nov 2019 21:46:26 +0000 (UTC) Date: Mon, 25 Nov 2019 16:46:25 -0500 From: Steven Rostedt To: "Frank A. Cancio Bello" Cc: Ingo Molnar , Jonathan Corbet , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, joel@joelfernandes.org, saiprakash.ranjan@codeaurora.org Subject: Re: [RFC v2 2/2] docs: ftrace: Fix typos Message-ID: <20191125164625.01101109@gandalf.local.home> In-Reply-To: <20191125123709.5eff70a9@gandalf.local.home> References: <20191125123709.5eff70a9@gandalf.local.home> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Mon, 25 Nov 2019 12:37:09 -0500 Steven Rostedt wrote: > On Sun, 24 Nov 2019 23:38:41 -0500 > "Frank A. Cancio Bello" wrote: > > > --- a/Documentation/trace/ring-buffer-design.txt > > +++ b/Documentation/trace/ring-buffer-design.txt > > @@ -37,7 +37,7 @@ commit_page - a pointer to the page with the last finished non-nested write. > > > > cmpxchg - hardware-assisted atomic transaction that performs the following: > > > > - A = B iff previous A == C > > + A = B if previous A == C > > This wasn't a typo. "iff" means "if and only if" which is a standard > notation. That is, this is shorthand for: > > A = B if previous A == C > previous A == C if A = B Although thinking about this more, this may not be correct. If previous A == B, then A = B, thus the "iff" notation is not actually accurate. This wouldn't then be a typo fix, but a real fix to the logic ;-) -- Steve > > > > > > R = cmpxchg(A, C, B) is saying that we replace A with B if and only if > > current A is equal to C, and we put the old (current) A into R > > --