Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752166AbbBVPSU (ORCPT ); Sun, 22 Feb 2015 10:18:20 -0500 Received: from mail-qg0-f50.google.com ([209.85.192.50]:49703 "EHLO mail-qg0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751890AbbBVPSR (ORCPT ); Sun, 22 Feb 2015 10:18:17 -0500 MIME-Version: 1.0 In-Reply-To: <20150222122754.GA7955@amd> References: <1409788535-28264-1-git-send-email-computersforpeace@gmail.com> <20150222082654.GB24441@norris-Latitude-E6410> <20150222122754.GA7955@amd> From: Kevin Cernekee Date: Sun, 22 Feb 2015 07:17:54 -0800 Message-ID: Subject: Re: [PATCH v2] PM / sleep: add configurable delay for pm_test To: Pavel Machek Cc: Brian Norris , "Rafael J. Wysocki" , Linux Kernel , linux-pm@vger.kernel.org, Len Brown , Florian Fainelli , Chirantan Ekbote Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1947 Lines: 48 On Sun, Feb 22, 2015 at 4:27 AM, Pavel Machek wrote: > On Sun 2015-02-22 00:26:54, Brian Norris wrote: >> 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 > > (Does this need documentation in kernel-parameters.txt or in place > where pm_test is documented?) Perhaps both places? Documentation/power/basic-pm-debugging.txt still has the "wait 5 seconds" verbiage. Beyond that, it looks good to me: Reviewed-by: Kevin Cernekee -- 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/