From mboxrd@z Thu Jan 1 00:00:00 1970 From: Srinivas Pandruvada Subject: Re: [RFT][PATCH 0/2] cpufreq: intel_pstate: Handle _PPC updates on global turbo disable/enable Date: Fri, 01 Mar 2019 09:39:27 -0800 Message-ID: References: <9956076.F4luUDm1Dq@aspire.rjw.lan> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <9956076.F4luUDm1Dq@aspire.rjw.lan> Sender: linux-kernel-owner@vger.kernel.org To: "Rafael J. Wysocki" , Linux PM Cc: LKML , Viresh Kumar , Chen Yu , Gabriele Mazzotta List-Id: linux-pm@vger.kernel.org On Fri, 2019-03-01 at 13:43 +0100, Rafael J. Wysocki wrote: > Hi All, > > This is how I would fix the issue reported in BZ 200759 (see this > patch series > from Yu too: https://marc.info/?l=linux-pm&m=155137672924029&w=2). > > Patch [1/2] causes intel_pstate to update all policies if it gets a > _PPC change > notification and sees a global turbo disable/enable change. > > Patch [2/2] makes it update cpuinfo.max_freq for all policies in > those cases. > > The patches here have not been tested yet, so testing would be much > appreciated. > > Of course, comments are welcome too! This is the only platform, someone reported such issue. Can we solve this by some udev rules and offline/online cpu 1-3 on power source change? There are examples of changing governors on power source change. https://bbs.archlinux.org/viewtopic.php?id=207186 Here instead of changing governor just echo 0 > /sys/devices/system/cpu/cpu1/online echo 1 > /sys/devices/system/cpu/cpu1/online echo 0 > /sys/devices/system/cpu/cpu2/online echo 1 > /sys/devices/system/cpu/cpu2/online echo 0 > /sys/devices/system/cpu/cpu3/online echo 1 > /sys/devices/system/cpu/cpu3/online Thanks, Srinivas > > Thanks, > Rafael >