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* [PATCH] Documentation, intel_pstate: Add a description of the intel_pstate internal governors
@ 2014-06-05 13:43 Prarit Bhargava
  2014-06-05 14:17 ` Viresh Kumar
  0 siblings, 1 reply; 7+ messages in thread
From: Prarit Bhargava @ 2014-06-05 13:43 UTC (permalink / raw)
  To: linux-kernel
  Cc: Prarit Bhargava, Dirk Brandewie, Randy Dunlap, Russell King,
	Jesper Nilsson, Viresh Kumar, David S. Miller,
	Ramkumar Ramachandra, Rafael J. Wysocki, linux-doc

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 <dirk.brandewie@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ramkumar Ramachandra <artagnon@gmail.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: linux-doc@vger.kernel.org

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
---
 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
+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


^ permalink raw reply	[flat|nested] 7+ messages in thread
* Re: [PATCH] Documentation, intel_pstate: Add a description of the intel_pstate internal governors [v3]
@ 2014-06-06  4:47 Viresh Kumar
  0 siblings, 0 replies; 7+ messages in thread
From: Viresh Kumar @ 2014-06-06  4:47 UTC (permalink / raw)
  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

On 5 June 2014 22:51, Prarit Bhargava <prarit@redhat.com> 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: Viresh Kumar <viresh.kumar@linaro.org>
> Cc: Dirk Brandewie <dirk.brandewie@gmail.com>
> Cc: Randy Dunlap <rdunlap@infradead.org>
> Cc: Russell King <linux@arm.linux.org.uk>
> Cc: Jesper Nilsson <jesper.nilsson@axis.com>
> Cc: Viresh Kumar <viresh.kumar@linaro.org>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Ramkumar Ramachandra <artagnon@gmail.com>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: linux-doc@vger.kernel.org
> Signed-off-by: Prarit Bhargava <prarit@redhat.com>
>
> [v2]: text update
> [v3]: text update

This will get into 'git logs' :(, you should have placed those below the ---
on the next line.

In case we are going to do a resend of this please change subject to:

I have seen some commits where [v3] in $subject is pushed into the logs,
but I am not sure if that's the right way. Why would we need to
know which version went into the kernel? In case maintainer
picked the wrong version we can simply check the diff..

cpufreq: documentation/intel_pstate: Add a description of the
intel_pstate internal governors

Anyway, I think Rafael might do these changes himself. So
don't resend it unless he asks for..

> ---
>  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..7e9db8f 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 generally used governors of the
> +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

Otherwise looks good:

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

^ permalink raw reply	[flat|nested] 7+ messages in thread
end of thread, other threads:[~2014-06-06  4:47 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-06-05 13:43 [PATCH] Documentation, intel_pstate: Add a description of the intel_pstate internal governors Prarit Bhargava
2014-06-05 14:17 ` Viresh Kumar
2014-06-05 15:07   ` [PATCH] Documentation, intel_pstate: Add a description of the intel_pstate internal governors [v2] Prarit Bhargava
2014-06-05 15:10     ` Dirk Brandewie
2014-06-05 16:58     ` Randy Dunlap
2014-06-05 17:21       ` [PATCH] Documentation, intel_pstate: Add a description of the intel_pstate internal governors [v3] Prarit Bhargava
2014-06-06  4:47 Viresh Kumar

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