From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756052AbaCOBtd (ORCPT ); Fri, 14 Mar 2014 21:49:33 -0400 Received: from v094114.home.net.pl ([79.96.170.134]:61866 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754591AbaCOBtb (ORCPT ); Fri, 14 Mar 2014 21:49:31 -0400 From: "Rafael J. Wysocki" To: dirk.brandewie@gmail.com Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, patrick.marlier@gmail.com, Dirk Brandewie Subject: Re: [PATCH v2 1/2] cpufreq: Add exit_prepare callback to cpufreq_driver interface Date: Sat, 15 Mar 2014 03:04:55 +0100 Message-ID: <3229882.l5W5UxujLO@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.14.0-rc6+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <1394831037-15553-2-git-send-email-dirk.j.brandewie@intel.com> References: <16035918.jZXKnQ3yiq@vostro.rjw.lan> <1394831037-15553-1-git-send-email-dirk.j.brandewie@intel.com> <1394831037-15553-2-git-send-email-dirk.j.brandewie@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Friday, March 14, 2014 02:03:56 PM dirk.brandewie@gmail.com wrote: > From: Dirk Brandewie > > This callback allows the driver to do clean up before the CPU is > completely down and its state cannot be modified. This is used > by the intel_pstate driver to reduce the requested P state prior to > the core going away. This is required because the requested P state > of the offline core is used to select the package P state. This > effectively sets the floor package P state to the requested P state on > the offline core. > > Signed-off-by: Dirk Brandewie > --- > Documentation/cpu-freq/cpu-drivers.txt | 8 +++++++- > drivers/cpufreq/cpufreq.c | 3 +++ > include/linux/cpufreq.h | 1 + > 3 files changed, 11 insertions(+), 1 deletion(-) > > diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt > index 8b1a445..79def80 100644 > --- a/Documentation/cpu-freq/cpu-drivers.txt > +++ b/Documentation/cpu-freq/cpu-drivers.txt > @@ -61,7 +61,13 @@ target_index - See below on the differences. > > And optionally > > -cpufreq_driver.exit - A pointer to a per-CPU cleanup function. > +cpufreq_driver.exit - A pointer to a per-CPU cleanup > + function called during CPU_POST_DEAD > + phase of cpu hotplug process. > + > +cpufreq_driver.stop - A pointer to a per-CPU stop function > + called during CPU_DOWN_PREPARE phase of > + cpu hotplug process. > > cpufreq_driver.resume - A pointer to a per-CPU resume function > which is called with interrupts disabled > diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c > index cf485d9..0d430d7 100644 > --- a/drivers/cpufreq/cpufreq.c > +++ b/drivers/cpufreq/cpufreq.c > @@ -1338,6 +1338,9 @@ static int __cpufreq_remove_dev_prepare(struct device *dev, > } > } > > + if (cpufreq_driver->stop) What about doing + if (cpufreq_driver->setpolicy && cpufreq_driver->stop) here instead? That would make it clear where the new callback belongs. If you're fine with that, I can make that change when applying the patch. > + cpufreq_driver->stop(policy); > + > return 0; > } > > diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h > index 4d89e0e..ff8db19 100644 > --- a/include/linux/cpufreq.h > +++ b/include/linux/cpufreq.h > @@ -224,6 +224,7 @@ struct cpufreq_driver { > int (*bios_limit) (int cpu, unsigned int *limit); > > int (*exit) (struct cpufreq_policy *policy); > + int (*stop) (struct cpufreq_policy *policy); > int (*suspend) (struct cpufreq_policy *policy); > int (*resume) (struct cpufreq_policy *policy); > struct freq_attr **attr; > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.