Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753910AbbHJHvg (ORCPT ); Mon, 10 Aug 2015 03:51:36 -0400 Received: from e28smtp04.in.ibm.com ([122.248.162.4]:53869 "EHLO e28smtp04.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753392AbbHJHvd (ORCPT ); Mon, 10 Aug 2015 03:51:33 -0400 X-Helo: d28dlp02.in.ibm.com X-MailFrom: shilpa.bhat@linux.vnet.ibm.com X-RcptTo: linux-pm@vger.kernel.org Message-ID: <55C857F8.6090502@linux.vnet.ibm.com> Date: Mon, 10 Aug 2015 13:21:20 +0530 From: Shilpasri G Bhat User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Stewart Smith , rjw@rjwysocki.net CC: linux-pm@vger.kernel.org, viresh.kumar@linaro.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, joel@jms.id.au Subject: Re: [PATCH v5 3/6] cpufreq: powernv: Register for OCC related opal_message notification References: <1437033863-15864-1-git-send-email-shilpa.bhat@linux.vnet.ibm.com> <1437033863-15864-4-git-send-email-shilpa.bhat@linux.vnet.ibm.com> In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15081007-0013-0000-0000-000006B7C1A5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3519 Lines: 105 On 08/10/2015 07:11 AM, Stewart Smith wrote: > Shilpasri G Bhat writes: >> diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c >> index d0c18c9..a634199 100644 >> --- a/drivers/cpufreq/powernv-cpufreq.c >> +++ b/drivers/cpufreq/powernv-cpufreq.c >> @@ -33,6 +33,7 @@ >> #include >> #include >> #include /* Required for cpu_sibling_mask() in UP configs */ >> +#include >> >> #define POWERNV_MAX_PSTATES 256 >> #define PMSR_PSAFE_ENABLE (1UL << 30) >> @@ -41,7 +42,7 @@ >> #define PMSR_LP(x) ((x >> 48) & 0xFF) >> >> static struct cpufreq_frequency_table powernv_freqs[POWERNV_MAX_PSTATES+1]; >> -static bool rebooting, throttled; >> +static bool rebooting, throttled, occ_reset; >> >> static struct chip { >> unsigned int id; >> @@ -414,6 +415,74 @@ static struct notifier_block powernv_cpufreq_reboot_nb = { >> .notifier_call = powernv_cpufreq_reboot_notifier, >> }; >> >> +static char throttle_reason[][30] = { >> + "No throttling", >> + "Power Cap", >> + "Processor Over Temperature", >> + "Power Supply Failure", >> + "Over Current", >> + "OCC Reset" >> + }; >> + >> +static int powernv_cpufreq_occ_msg(struct notifier_block *nb, >> + unsigned long msg_type, void *_msg) >> +{ >> + struct opal_msg *msg = _msg; >> + struct opal_occ_msg omsg; >> + >> + if (msg_type != OPAL_MSG_OCC) >> + return 0; >> + >> + omsg.type = be64_to_cpu(msg->params[0]); >> + >> + switch (omsg.type) { >> + case OCC_RESET: >> + occ_reset = true; >> + /* >> + * powernv_cpufreq_throttle_check() is called in >> + * target() callback which can detect the throttle state >> + * for governors like ondemand. >> + * But static governors will not call target() often thus >> + * report throttling here. >> + */ >> + if (!throttled) { >> + throttled = true; >> + pr_crit("CPU Frequency is throttled\n"); >> + } >> + pr_info("OCC: Reset\n"); >> + break; >> + case OCC_LOAD: >> + pr_info("OCC: Loaded\n"); >> + break; > > I wonder if we could have the log messages be a bit clearer here, odds > are, unless you're one of the people reading this code, you have no idea > what an OCC is or what on earth "OCC: Loaded" means and why this > *doesn't* mean that your CPUs are no longer throttled so that your > computer doesn't catch fire/break/add 1+1 and get 4. > > Also, do we export this information via sysfs somewhere? It would seem > to want to go along with other cpufreq/cpu info there. No we don't export the throttling status of the cpu via sysfs. Since the throttling state is common across the chip, the per_cpu export will be redundant. Did you mean something like one of the below: 1)/sys/devices/system/cpu/cpufreq/chipN_throttle 2)/sys/devices/system/cpu/cpuN/cpufreq/throttle > > It feels like we could do much better at informing users as to what is > going on.... maybe something like: > > "OCC (On Chip Controller - enforces hard thermal/power limits) Resetting: CPU frequency throttled for duration" > "OCC Loading, CPU frequency throttled until OCC started" > "OCC Active, CPU frequency no longer throttled" > Okay will change the messages. Thanks and Regards, Shilpa -- 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/