[PATCH 3/4] cpufreq: intel_pstate: New sysfs entry to control HWP boost

From: Srinivas Pandruvada
Date: Tue Jun 05 2018 - 17:43:44 EST


A new attribute is added to intel_pstate sysfs to enable/disable
HWP dynamic performance boost.

Reported-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Tested-by: Giovanni Gherdovich <ggherdovich@xxxxxxx>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
---
drivers/cpufreq/intel_pstate.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 5b2b6b6d1ff4..70bf63bb4e0e 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -1033,6 +1033,30 @@ static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
return count;
}

+static ssize_t show_hwp_dynamic_boost(struct kobject *kobj,
+ struct attribute *attr, char *buf)
+{
+ return sprintf(buf, "%u\n", hwp_boost);
+}
+
+static ssize_t store_hwp_dynamic_boost(struct kobject *a, struct attribute *b,
+ const char *buf, size_t count)
+{
+ unsigned int input;
+ int ret;
+
+ ret = kstrtouint(buf, 10, &input);
+ if (ret)
+ return ret;
+
+ mutex_lock(&intel_pstate_driver_lock);
+ hwp_boost = !!input;
+ intel_pstate_update_policies();
+ mutex_unlock(&intel_pstate_driver_lock);
+
+ return count;
+}
+
show_one(max_perf_pct, max_perf_pct);
show_one(min_perf_pct, min_perf_pct);

@@ -1042,6 +1066,7 @@ define_one_global_rw(max_perf_pct);
define_one_global_rw(min_perf_pct);
define_one_global_ro(turbo_pct);
define_one_global_ro(num_pstates);
+define_one_global_rw(hwp_dynamic_boost);

static struct attribute *intel_pstate_attributes[] = {
&status.attr,
@@ -1082,6 +1107,11 @@ static void __init intel_pstate_sysfs_expose_params(void)
rc = sysfs_create_file(intel_pstate_kobject, &min_perf_pct.attr);
WARN_ON(rc);

+ if (hwp_active) {
+ rc = sysfs_create_file(intel_pstate_kobject,
+ &hwp_dynamic_boost.attr);
+ WARN_ON(rc);
+ }
}
/************************** sysfs end ************************/

--
2.13.6