Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753208AbaGaPgC (ORCPT ); Thu, 31 Jul 2014 11:36:02 -0400 Received: from e28smtp04.in.ibm.com ([122.248.162.4]:42324 "EHLO e28smtp04.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751381AbaGaPf7 (ORCPT ); Thu, 31 Jul 2014 11:35:59 -0400 Subject: [PATCH v2 1/2] printk: Add function to return log buffer address and size To: linux-kernel@vger.kernel.org From: Vasant Hegde Cc: linuxppc-dev@lists.ozlabs.org, Andrew Morton , Linus Torvalds , Benjamin Herrenschmidt Date: Thu, 31 Jul 2014 21:05:48 +0530 Message-ID: <20140731153447.27134.44225.stgit@hegdevasant.in.ibm.com> User-Agent: StGit/0.16 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable x-cbid: 14073115-5564-0000-0000-00000063F691 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Platforms like IBM Power Systems supports service processor assisted dump. It provides interface to add memory region to be captured when system is crashed. During initialization/running we can add kernel memory region to be collected. Presently we don't have a way to get the log buffer base address and size. This patch adds support to return log buffer address and size. Signed-off-by: Vasant Hegde --- Next patch extends arch specific code to add log buffer to platform dump. -Vasant include/linux/printk.h | 3 +++ kernel/printk/printk.c | 12 ++++++++++++ 2 files changed, 15 insertions(+) diff --git a/include/linux/printk.h b/include/linux/printk.h index 319ff7e..aae82c4 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -10,6 +10,9 @@ extern const char linux_banner[]; extern const char linux_proc_banner[]; +extern void *get_log_buf_addr(void); +extern u32 get_log_buf_len(void); + static inline int printk_get_level(const char *buffer) { if (buffer[0] == KERN_SOH_ASCII && buffer[1]) { diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 13e839d..4049f7b 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -270,6 +270,18 @@ static char __log_buf[__LOG_BUF_LEN] __aligned(LOG_ALIGN); static char *log_buf = __log_buf; static u32 log_buf_len = __LOG_BUF_LEN; +/* Return log buffer address */ +void *get_log_buf_addr(void) +{ + return log_buf; +} + +/* Return log buffer size */ +u32 get_log_buf_len(void) +{ + return log_buf_len; +} + /* human readable text of the record */ static char *log_text(const struct printk_log *msg) { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/