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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF3B1C4332F for ; Mon, 11 Dec 2023 23:13:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345312AbjLKXNH (ORCPT ); Mon, 11 Dec 2023 18:13:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57636 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345166AbjLKXNG (ORCPT ); Mon, 11 Dec 2023 18:13:06 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 858119A for ; Mon, 11 Dec 2023 15:13:13 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 904BFC433C8; Mon, 11 Dec 2023 23:13:12 +0000 (UTC) Date: Mon, 11 Dec 2023 18:13:52 -0500 From: Steven Rostedt To: Mathieu Desnoyers Cc: linux-kernel@vger.kernel.org, Masami Hiramatsu , linux-trace-kernel@vger.kernel.org Subject: Re: [RFC PATCH] ring-buffer: Fix and comment ring buffer rb_time functions on 32-bit Message-ID: <20231211181352.088aeef5@gandalf.local.home> In-Reply-To: <20231211175904.29e01e8b@gandalf.local.home> References: <20231211201324.652870-1-mathieu.desnoyers@efficios.com> <20231211175904.29e01e8b@gandalf.local.home> X-Mailer: Claws Mail 3.19.1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 11 Dec 2023 17:59:04 -0500 Steven Rostedt wrote: > > > > - A cmpxchg interrupted by 4 writes or cmpxchg overflows the counter > > and produces corrupted time stamps. This is _not_ fixed by this patch. > > Except that it's not 4 bits that is compared, but 32 bits. That should be "not 2 bits", as in "shave and a hair cut!" ;-) -- Steve