From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755982Ab2GKJSA (ORCPT ); Wed, 11 Jul 2012 05:18:00 -0400 Received: from b.relay.invitel.net ([62.77.203.4]:37996 "EHLO b.relay.invitel.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751835Ab2GKJR6 (ORCPT ); Wed, 11 Jul 2012 05:17:58 -0400 X-Greylist: delayed 533 seconds by postgrey-1.27 at vger.kernel.org; Wed, 11 Jul 2012 05:17:58 EDT Date: Wed, 11 Jul 2012 11:08:58 +0200 From: Heiko Schocher Subject: Re: [RFC] kernel, logbuf: add support for external log buffer In-reply-to: <1339395188-10166-1-git-send-email-hs@denx.de> To: Heiko Schocher Cc: linux-arm-kernel@lists.infradead.org, Igor Lisitsin , Wolfgang Denk , Grant Erickson , linux-kernel@vger.kernel.org, Tim Bird , CE Linux Developers List , Kay Sievers Reply-to: hs@denx.de Message-id: <4FFD42AA.8090301@denx.de> Organization: DENX Software Engineering MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-15; format=flowed Content-transfer-encoding: 7BIT References: <1339395188-10166-1-git-send-email-hs@denx.de> User-Agent: Mozilla/5.0 (X11; Linux i686; rv:12.0) Gecko/20120421 Thunderbird/12.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On 11.06.2012 08:13, Heiko Schocher wrote: > This merges support for the previously DENX-only kernel > feature of specifying an alternative, "external" buffer > for kernel printk messages and their associated metadata. > This patch is based on DENX-only kernel commit: > > commit 212f61c7fd3b952a81d1459dd32a86a32ddfd4ce > Author: Igor Lisitsin > Date: Wed Apr 18 14:55:19 2007 +0400 > > Add support for external log buffer. > > Add support for external log buffer, for example passed by U-Boot, > which may already contain messages (from the boot loader and/or POST). > > Signed-off-by: Igor Lisitsin > > see: > http://git.denx.de/?p=linux-denx.git;a=commit;h=212f61c7fd3b952a81d1459dd32a86a32ddfd4ce > > When this option is enabled, an architecture- or machine-specific log > buffer is used for all printk messages. This allows entities such as > boot loaders (e.g. U-Boot) to place printk-compatible messages into > this buffer and for the kernel to coalesce them with its normal > messages. This patch support this feature for arch/arm based > boards. > > Signed-off-by: Heiko Schocher > Cc: Wolfgang Denk > Cc: Igor Lisitsin > Cc: Grant Erickson > Cc: linux-kernel@vger.kernel.org > Cc: Tim Bird > Cc: CE Linux Developers List > Cc: Kay Sievers > > --- > restage prior discussion from lkml: > > https://lkml.org/lkml/2009/1/21/250 > > Discussion stopped, and I want to reanimate it, also there is a > Project Proposal on the "CE Linux Developers List" for such a feature, > see here: > > http://www.mail-archive.com/celinux-dev@lists.celinuxforum.org/msg00103.html > > Maybe it is now the time to discuss this again? > > Is it worth to try to get this old code in current kernel, or > should we investigate Kay Sievers proposal for a structured logging > system, which will alter the format of the messages as they are > stored in the log buffer, and discuss for this a "logbuffer support"? > > See this discussion here: > > http://thread.gmane.org/gmane.linux.kernel/1277619 > > arch/arm/mm/init.c | 25 ++++++++++ > include/linux/logbuff.h | 51 ++++++++++++++++++++ > init/Kconfig | 12 +++++ > init/main.c | 5 ++ > kernel/printk.c | 117 +++++++++++++++++++++++++++++++++++++++++++++-- > 5 files changed, 206 insertions(+), 4 deletions(-) > create mode 100644 include/linux/logbuff.h ping? I got no respond to this RFC ... no chance to get this to mainline? bye, Heiko -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany