From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e28smtp04.in.ibm.com (e28smtp04.in.ibm.com [122.248.162.4]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e28smtp04.in.ibm.com", Issuer "GeoTrust SSL CA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 20D192C00F4 for ; Fri, 26 Apr 2013 19:56:02 +1000 (EST) Received: from /spool/local by e28smtp04.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 26 Apr 2013 15:21:33 +0530 Received: from d28relay02.in.ibm.com (d28relay02.in.ibm.com [9.184.220.59]) by d28dlp02.in.ibm.com (Postfix) with ESMTP id EFB113940059 for ; Fri, 26 Apr 2013 15:25:56 +0530 (IST) Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay02.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r3Q9tqG666977942 for ; Fri, 26 Apr 2013 15:25:52 +0530 Received: from d28av04.in.ibm.com (loopback [127.0.0.1]) by d28av04.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r3Q9tstS006162 for ; Fri, 26 Apr 2013 19:55:56 +1000 Subject: [RFC PATCH 0/3] Nvram-to-pstore: compression support for oops data To: linuxppc-dev@ozlabs.org, paulus@samba.org, linux-kernel@vger.kernel.org, benh@kernel.crashing.org From: Aruna Balakrishnaiah Date: Fri, 26 Apr 2013 15:25:54 +0530 Message-ID: <20130426094923.14323.80567.stgit@aruna-ThinkPad-T420> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Cc: jkenisto@linux.vnet.ibm.com, tony.luck@intel.com, mahesh@linux.vnet.ibm.com, cbouatmailru@gmail.com, anton@samba.org, ccross@android.com, keescook@chromium.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , The patchset takes care of compressing oops messages while writing to NVRAM, so that more oops data can be captured in the given space. big_oops_buf (2.22 * oops_data_sz) is allocated for compression. oops_data_sz is oops header size less of oops partition size. Pstore will internally call kmsg_dump to capture messages from printk buffer. While returning the data to nvram it adds is own header. For compression: Register pstore with big_oops_buf. In case compression fails, copy header added by pstore and last oops_data_sz bytes (recent messages) of big_oops_buf to nvram for which we need to know header size. patch 01/03 will add a function in pstore to return the header size. pstore read callback of nvram will read the compressed data and return the decompressed data so that dmesg file (under /dev/pstore) is readable. In case decompression fails, instead of having the compressed data (junk) in the dmesg file it will skip and continue reading other partitions. This results in absence of dmesg file but will still have files relating to other parititons. --- Aruna Balakrishnaiah (3): Retreive header size from pstore. powerpc/pseries: Re-organise the oops compression code powerpc/pseries: Support compression of oops text via pstore arch/powerpc/platforms/pseries/nvram.c | 236 +++++++++++++++++++++++--------- fs/pstore/platform.c | 7 + include/linux/pstore.h | 6 + 3 files changed, 182 insertions(+), 67 deletions(-) --