Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751989AbaFEORO (ORCPT ); Thu, 5 Jun 2014 10:17:14 -0400 Received: from mail-oa0-f44.google.com ([209.85.219.44]:57307 "EHLO mail-oa0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751015AbaFEORM (ORCPT ); Thu, 5 Jun 2014 10:17:12 -0400 MIME-Version: 1.0 In-Reply-To: <1401975821-3972-1-git-send-email-prarit@redhat.com> References: <1401975821-3972-1-git-send-email-prarit@redhat.com> Date: Thu, 5 Jun 2014 19:47:12 +0530 Message-ID: Subject: Re: [PATCH] Documentation, intel_pstate: Add a description of the intel_pstate internal governors From: Viresh Kumar To: Prarit Bhargava Cc: Linux Kernel Mailing List , Dirk Brandewie , Randy Dunlap , Russell King , Jesper Nilsson , "David S. Miller" , Ramkumar Ramachandra , "Rafael J. Wysocki" , "linux-doc@vger.kernel.org" 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 5 June 2014 19:13, Prarit Bhargava wrote: > The current documentation is incomplete wrt the intel_pstate internal > governors. The confusion comes from the general use internal governors > which also use the names performance and powersave. This patch > differentiates between the two sets of governors. > > Cc: Dirk Brandewie > Cc: Randy Dunlap > Cc: Russell King > Cc: Jesper Nilsson > Cc: Viresh Kumar > Cc: "David S. Miller" > Cc: Ramkumar Ramachandra > Cc: "Rafael J. Wysocki" > Cc: linux-doc@vger.kernel.org > > Signed-off-by: Prarit Bhargava > --- > Documentation/cpu-freq/governors.txt | 2 +- > Documentation/cpu-freq/intel-pstate.txt | 8 ++++++++ > 2 files changed, 9 insertions(+), 1 deletion(-) > > diff --git a/Documentation/cpu-freq/governors.txt b/Documentation/cpu-freq/governors.txt > index 77ec215..c15aa75 100644 > --- a/Documentation/cpu-freq/governors.txt > +++ b/Documentation/cpu-freq/governors.txt > @@ -36,7 +36,7 @@ Contents: > 1. What Is A CPUFreq Governor? > ============================== > > -Most cpufreq drivers (in fact, all except one, longrun) or even most > +Most cpufreq drivers (except the intel_pstate and longrun) or even most > cpu frequency scaling algorithms only offer the CPU to be set to one > frequency. In order to offer dynamic frequency scaling, the cpufreq > core must be able to tell these drivers of a "target frequency". So > diff --git a/Documentation/cpu-freq/intel-pstate.txt b/Documentation/cpu-freq/intel-pstate.txt > index e742d21..ce894cc 100644 > --- a/Documentation/cpu-freq/intel-pstate.txt > +++ b/Documentation/cpu-freq/intel-pstate.txt > @@ -9,6 +9,14 @@ assumed to implement internal governors by the cpufreq core. All the > logic for selecting the current P state is contained within the > driver; no external governor is used by the cpufreq core. > > +The Intel P-state driver has two internal governors, performance and > +powersave. These governors differ from the general use governors of the s/general use/generally used ?? > +same name in the kernel. The internal performance governor sets the > +max_perf_pct and min_perf_pct to 100; that is, the governor selects the > +highest available P state to maximize the performance of the core. The > +internal powersave governor, selects the appropriate P state based on the > +current load on the CPU. > + > Intel SandyBridge+ processors are supported. > > New sysfs files for controlling P state selection have been added to > -- > 1.7.9.3 > -- 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/