[PATCH 2/6] cpufreq: Add sampling_window tunable

Youquan Song
2010-12-23T06:21:19Z

Add sampling_window tunable and user can set sampling window size by this
interface. The default max sampling window is one second.

Signed-off-by: Youquan Song <youquan.song@intel.com>
---
drivers/cpufreq/cpufreq_ondemand.c | 26 ++++++++++++++++++++++++++
1 files changed, 26 insertions(+), 0 deletions(-)

diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index e49b2e1..87aec7f 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -295,6 +295,7 @@ show_one(up_threshold, up_threshold);
show_one(sampling_down_factor, sampling_down_factor);
show_one(ignore_nice_load, ignore_nice);
show_one(powersave_bias, powersave_bias);
+show_one(sampling_window, sampling_window);

/*** delete after deprecation time ***/

@@ -455,12 +456,36 @@ static ssize_t store_powersave_bias(struct kobject *a, struct attribute *b,
return count;
}

+static ssize_t store_sampling_window(struct kobject *a, struct attribute *b,
+ const char *buf, size_t count)
+{
+ unsigned int input;
+ int ret;
+ ret = sscanf(buf, "%u", &input);
+
+ if (ret != 1)
+ return -EINVAL;
+
+ if (input > 1000000)
+ input = 1000000;
+
+ if (input < 10000)
+ input = 10000;
+
+ mutex_lock(&dbs_mutex);
+ dbs_tuners_ins.sampling_window = input;
+ mutex_unlock(&dbs_mutex);
+
+ return count;
+}
+
define_one_global_rw(sampling_rate);
define_one_global_rw(io_is_busy);
define_one_global_rw(up_threshold);
define_one_global_rw(sampling_down_factor);
define_one_global_rw(ignore_nice_load);
define_one_global_rw(powersave_bias);
+define_one_global_rw(sampling_window);

static struct attribute *dbs_attributes[] = {
&sampling_rate_max.attr,
@@ -471,6 +496,7 @@ static struct attribute *dbs_attributes[] = {
&ignore_nice_load.attr,
&powersave_bias.attr,
&io_is_busy.attr,
+ &sampling_window.attr,
NULL
};

--
1.6.4.2