From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3BDF31A186B for ; Tue, 12 Jan 2016 09:23:15 +1100 (AEDT) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id E3C7114032F for ; Tue, 12 Jan 2016 09:23:14 +1100 (AEDT) Date: Mon, 11 Jan 2016 14:23:12 -0800 From: Greg KH To: Shilpasri G Bhat Cc: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, rjw@rjwysocki.net, viresh.kumar@linaro.org, linux-pm@vger.kernel.org, pc@us.ibm.com, anton@samba.org, ego@linux.vnet.ibm.com, stable@vger.kernel.org Subject: Re: [PATCH v4 0/4] cpufreq: powernv: Redesign the presentation of throttle notification Message-ID: <20160111222312.GA3967@kroah.com> References: <1451899527-14359-1-git-send-email-shilpa.bhat@linux.vnet.ibm.com> <1452545680-11976-1-git-send-email-shilpa.bhat@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1452545680-11976-1-git-send-email-shilpa.bhat@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, Jan 11, 2016 at 02:54:36PM -0600, Shilpasri G Bhat wrote: > In POWER8, OCC(On-Chip-Controller) can throttle the frequency of the > CPU when the chip crosses its thermal and power limits. Currently, > powernv-cpufreq driver detects and reports this event as a console > message. Some machines may not sustain the max turbo frequency in all > conditions and can be throttled frequently. This can lead to the > flooding of console with throttle messages. So this patchset aims to > redesign the presentation of this event via sysfs counters and > tracepoints. > > Patches [2] to [4] will add a perf trace point "power:powernv_throttle" and > sysfs throttle counter stats in /sys/devices/system/cpu/cpufreq/chipN. > Patch [1] solves a bug in powernv_cpufreq_throttle_check(), which calls in to > cpu_to_chip_id() in hot path which reads DT every time to find the chip id. This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read Documentation/stable_kernel_rules.txt for how to do this properly.