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 8FA79C74A5B for ; Wed, 29 Mar 2023 13:14:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229631AbjC2NOj (ORCPT ); Wed, 29 Mar 2023 09:14:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35342 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229500AbjC2NOi (ORCPT ); Wed, 29 Mar 2023 09:14:38 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0EADA26BA; Wed, 29 Mar 2023 06:14:38 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 9992B61CEB; Wed, 29 Mar 2023 13:14:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 49D76C433D2; Wed, 29 Mar 2023 13:14:36 +0000 (UTC) Date: Wed, 29 Mar 2023 09:14:29 -0400 From: Steven Rostedt To: Vincent Donnefort Cc: mhiramat@kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, kernel-team@android.com Subject: Re: [PATCH v2 1/2] ring-buffer: Introducing ring-buffer mapping functions Message-ID: <20230329091429.03d52dcc@rorschach.local.home> In-Reply-To: References: <20230322102244.3239740-1-vdonnefort@google.com> <20230322102244.3239740-2-vdonnefort@google.com> <20230328224411.0d69e272@gandalf.local.home> <20230329070353.1e1b443b@gandalf.local.home> <20230329084735.6c4a9229@rorschach.local.home> X-Mailer: Claws Mail 3.17.8 (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-trace-kernel@vger.kernel.org On Wed, 29 Mar 2023 14:10:09 +0100 Vincent Donnefort wrote: > The v2 of this series only updates the head page in the update ioctl > (ring_buffer_update_meta_page()) Couldn't find a nice way around that as it can > be either updated by the reader or the writer. So the best solution seemed a > call to set_head_page(). Yes, the update will race between readers and writers. Let's not worry about this at the moment and not expose it yet. I'm looking at other ways around this too. -- Steve