From patchwork Sun Feb 22 08:26:54 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Norris X-Patchwork-Id: 5861521 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 1B6EF9F169 for ; Sun, 22 Feb 2015 08:27:04 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8A10720562 for ; Sun, 22 Feb 2015 08:27:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7EDB420557 for ; Sun, 22 Feb 2015 08:27:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751288AbbBVI07 (ORCPT ); Sun, 22 Feb 2015 03:26:59 -0500 Received: from mail-pd0-f181.google.com ([209.85.192.181]:36787 "EHLO mail-pd0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751243AbbBVI06 (ORCPT ); Sun, 22 Feb 2015 03:26:58 -0500 Received: by pdjp10 with SMTP id p10so18092997pdj.3; Sun, 22 Feb 2015 00:26:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=RfIC5F1f2NDD/cfXctcs6SmqRrHjHSqaggtmruBCbaI=; b=w8Onm9x2gETb0DQiswtp3K2hEigfzAWI2JA3TtSskIA0+K2TQBLvTKm98qePrOFT3V 6eceA/W4dvj5bxEhL8wBdDHLuc3J/Qhl7LvZyCM2g2xHjgB/grJdOViiWuoFdKT4Vb9n mTlRfTp6UWKhujpYlJ3b7P6ENJ6K8qKU09n4z3qaCwxruVkvW0d2490yr2pWFFqxNFdI anqinwsWsym2hb2wicvwf1KDIhw8JA3RsD03oWFT3xtkD5ImkbnIJE1dXK3BhnJv4KSW RmwtNvcxfUvhq9QqHYxRfoS2UcyA/Gub79RDLCpTnkkAjDYUzEwnkyh7PsU2080Srshg Qe1A== X-Received: by 10.70.35.15 with SMTP id d15mr9926870pdj.61.1424593618344; Sun, 22 Feb 2015 00:26:58 -0800 (PST) Received: from norris-Latitude-E6410 (cpe-76-169-7-156.socal.res.rr.com. [76.169.7.156]) by mx.google.com with ESMTPSA id mt4sm32111247pdb.55.2015.02.22.00.26.57 (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Sun, 22 Feb 2015 00:26:57 -0800 (PST) Date: Sun, 22 Feb 2015 00:26:54 -0800 From: Brian Norris To: "Rafael J. Wysocki" Cc: Linux Kernel , linux-pm@vger.kernel.org, Len Brown , Pavel Machek , Florian Fainelli , Kevin Cernekee , Chirantan Ekbote Subject: [PATCH v2] PM / sleep: add configurable delay for pm_test Message-ID: <20150222082654.GB24441@norris-Latitude-E6410> References: <1409788535-28264-1-git-send-email-computersforpeace@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1409788535-28264-1-git-send-email-computersforpeace@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Spam-Status: No, score=-6.8 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, T_DKIM_INVALID, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When CONFIG_PM_DEBUG=y, we provide a sysfs file (/sys/power/pm_test) for selecting one of a few suspend test modes, where rather than entering a full suspend state, the kernel will perform some subset of suspend steps, wait 5 seconds, and then resume back to normal operation. This mode is useful for (among other things) observing the state of the system just before entering a sleep mode, for debugging or analysis purposes. However, a constant 5 second wait is not sufficient for some sorts of analysis; for example, on an SoC, one might want to use external tools to probe the power states of various on-chip controllers or clocks. This patch turns this 5 second delay into a configurable module parameter, so users can determine how long to wait in this pseudo-suspend state before resuming the system. Example (wait 30 seconds); # echo 30 > /sys/module/suspend/parameters/pm_test_delay # echo core > /sys/power/pm_test # time echo mem > /sys/power/state ... [ 17.583625] suspend debug: Waiting for 30 second(s). ... real 0m30.381s user 0m0.017s sys 0m0.080s Signed-off-by: Brian Norris Acked-by: Pavel Machek Reviewed-by: Kevin Cernekee Acked-by: Florian Fainelli --- v2: - make this a module param instead of an explicit sysfs file - drop the for loop; mdelay() does the same loop internally - decrease +36 lines of code and +2 lines of doc, to +6 lines of code and +2 lines of doc kernel/power/suspend.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index c347e3ce3a55..aee23dab0a55 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -28,6 +28,7 @@ #include #include #include +#include #include "power.h" @@ -204,12 +205,20 @@ static bool platform_suspend_again(suspend_state_t state) suspend_ops->suspend_again() : false; } +#ifdef CONFIG_PM_DEBUG +static unsigned int pm_test_delay = 5; +module_param(pm_test_delay, uint, 0644); +MODULE_PARM_DESC(pm_test_delay, + "Number of seconds to wait before resuming from suspend test"); +#endif + static int suspend_test(int level) { #ifdef CONFIG_PM_DEBUG if (pm_test_level == level) { - printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n"); - mdelay(5000); + printk(KERN_INFO "suspend debug: Waiting for %d second(s).\n", + pm_test_delay); + mdelay(pm_test_delay * 1000); return 1; } #endif /* !CONFIG_PM_DEBUG */