From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755024Ab1HWDFb (ORCPT ); Mon, 22 Aug 2011 23:05:31 -0400 Received: from mga09.intel.com ([134.134.136.24]:60222 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754931Ab1HWDF1 (ORCPT ); Mon, 22 Aug 2011 23:05:27 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,352,1309762800"; d="scan'208";a="41170840" Subject: [PATCH V2] printk:add console_suspend module parameter From: Yanmin Zhang Reply-To: yanmin_zhang@linux.intel.com To: LKML Cc: Andrew Morton Content-Type: text/plain; charset="UTF-8" Organization: UMG Date: Tue, 23 Aug 2011 11:04:32 +0800 Message-ID: <1314068672.1749.6.camel@ymzhang> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We are enabling some power features on medfield. To test suspend-2-RAM conveniently, we need turn on/off console_suspend_enabled frequently. Below patch adds a module parameter, so users could change it by: /sys/module/printk/parameters/console_suspend Signed-off-by: Yanmin Zhang --- Documentation/kernel-parameters.txt | 5 +++++ kernel/printk.c | 4 ++++ 2 files changed, 9 insertions(+), 0 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 614d038..74446e0 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1642,6 +1642,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. debugging driver suspend/resume hooks). This may not work reliably with all consoles, but is known to work with serial and VGA consoles. + To facilitate more flexible debugging, we also add + console_suspend, a printk module parameter to control + it. Users could use console_suspend (usually + /sys/module/printk/parameters/console_suspend) to + turn on/off it dynamically. noaliencache [MM, NUMA, SLAB] Disables the allocation of alien caches in the slab allocator. Saves per-node memory, diff --git a/kernel/printk.c b/kernel/printk.c index 836a2ae..b9ef93a 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -1108,6 +1108,10 @@ static int __init console_suspend_disable(char *str) return 1; } __setup("no_console_suspend", console_suspend_disable); +module_param_named(console_suspend, console_suspend_enabled, + bool, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(console_suspend, "suspend console during suspend" + " and hibernate operations"); /** * suspend_console - suspend the console subsystem -- 1.7.1