From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752731AbcGKURL (ORCPT ); Mon, 11 Jul 2016 16:17:11 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:41536 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752510AbcGKURK (ORCPT ); Mon, 11 Jul 2016 16:17:10 -0400 Date: Mon, 11 Jul 2016 13:17:09 -0700 From: Andrew Morton To: akash.goel@intel.com Cc: linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk, Eduard - Gabriel Munteanu , Tom Zanussi , Chris Wilson Subject: Re: [PATCH v2] relay: Add global mode support for buffer-only channels Message-Id: <20160711131709.4b2417f54b2eb9fd0fa19900@linux-foundation.org> In-Reply-To: <1468221456-15537-1-git-send-email-akash.goel@intel.com> References: <1468221456-15537-1-git-send-email-akash.goel@intel.com> X-Mailer: Sylpheed 3.4.1 (GTK+ 2.24.23; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 11 Jul 2016 12:47:36 +0530 akash.goel@intel.com wrote: > From: Akash Goel > > The following patch added support to use channels with no associated files. > relay: add buffer-only channels; useful for early logging hm, 8 years ago. Normally we refer to previous commits using the form 20d8b67c06fa5e74f44e ("relay: add buffer-only channels; useful for early logging"). But this one is so old that we should inform readers about its vintage, so this form: commit 20d8b67c06fa5e74f44e80b0a0fd68c8327f7c6a Author: Eduard - Gabriel Munteanu Date: Fri Jul 25 19:45:12 2008 -0700 relay: add buffer-only channels; useful for early logging would be better. > This is useful when the exact location of relay file is not known or the > the parent directory of relay file is not available, while creating the > channel and the logging has to start right from the boot. > > But there was no provision to use global mode with buffer-only channels, > which is added by this patch, without modifying the interface where initially > there will be a dummy invocation of create_buf_file callback through which > kernel client can convey the need of a global buffer. > > For the use case where drivers/kernel clients want a simple interface for the > userspace, which enables them to capture data/logs from relay file in order & > without any post processing, support of Global buffer mode is warranted. > > ... > > @@ -706,6 +727,7 @@ int relay_late_setup_files(struct rchan *chan, > > return err; > } > +EXPORT_SYMBOL_GPL(relay_late_setup_files); The export is unneeded and undocumented.