lkml.org 
[lkml]   [2010]   [Mar]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 3/3] cpufreq: add sysfs knob for toggling core performance boost
On Wed, 3 Mar 2010 14:59:27 -0600
Mark Langsdorf <mark.langsdorf@amd.com> wrote:

> >From 1ba7af20a37b72a4375d3e3ddd33a033f204ee21 Mon Sep 17 00:00:00 2001
> From: Mark Langsdorf <mark.langsdorf@amd.com>
> Date: Wed, 3 Mar 2010 14:34:47 -0600
> Subject: [PATCH 2/2] cpufreq: add sysfs knob for toggling core performance boost
>
> Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
> Tested-by: Mark Langsdorf <mark.langsdorf@amd.com>

The lack of any changelog in a patch is usually a good sign that the
patch needs a changelog :(

> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index 67bc2ec..e0fe93f 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -662,6 +662,30 @@ static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf)
> return sprintf(buf, "%u\n", policy->cpuinfo.max_freq);
> }
>
> +static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
> + size_t count)
> +{
> + int ret = -EINVAL;
> + unsigned long val = 0;
> +
> + ret = strict_strtoul(buf, 10, &val);
> + if (!ret && (val == 0 || val == 1))
> + policy->flags.cpb = val;
> + else
> + return -EINVAL;
> +
> + ret = __cpufreq_driver_target(policy, policy->cur, CPUFREQ_RELATION_H);
> + if (ret)
> + return -EINVAL;
> +
> + return count;
> +}
> +
> +static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
> +{
> + return sprintf(buf, "%u\n", policy->flags.cpb);
> +}
> +
> #define define_one_ro(_name) \
> static struct freq_attr _name = \
> __ATTR(_name, 0444, show_##_name, NULL)
> @@ -688,6 +712,7 @@ define_one_rw(scaling_min_freq);
> define_one_rw(scaling_max_freq);
> define_one_rw(scaling_governor);
> define_one_rw(scaling_setspeed);
> +define_one_rw(cpb);
>
> static struct attribute *default_attrs[] = {
> &cpuinfo_min_freq.attr,
> @@ -701,6 +726,7 @@ static struct attribute *default_attrs[] = {
> &scaling_driver.attr,
> &scaling_available_governors.attr,
> &scaling_setspeed.attr,
> + &cpb.attr,
> NULL
> };

Well I've read the code and I've read the code comments and I've read
the changelogs and I still have no clue what this thing does.
Apparently it allows me to toggle something called "APERF/MPERF". I
guess if I were patient enough, teh goog might tell me what that is,
and why I might want it. But this is all terribly inefficient.

I think you'd find that your feature is more useful and will be used by
more people if you tell them (and us) what it does.



\
 
 \ /
  Last update: 2010-03-04 22:31    [W:0.085 / U:0.192 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site