linux-kernel - [PATCH 06/70] cpufreq: interactive: configurable delay before raising above hispeed

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Date:	Tue, 27 Oct 2015 18:29:54 +0100
From:	Bálint Czobor <czoborbalint@...il.com>
To:	"Rafael J. Wysocki" <rjw@...ysocki.net>,
	Viresh Kumar <viresh.kumar@...aro.org>
Cc:	linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org,
	Todd Poynor <toddpoynor@...gle.com>,
	Bálint Czobor <czoborbalint@...il.com>
Subject: [PATCH 06/70] cpufreq: interactive: configurable delay before raising above hispeed

From: Todd Poynor <toddpoynor@...gle.com>

Change-Id: I4d6ac40b23a3790d48e30c37408284e9f955e8fa
Signed-off-by: Todd Poynor <toddpoynor@...gle.com>
Signed-off-by: Bálint Czobor <czoborbalint@...il.com>
---
 drivers/cpufreq/cpufreq_interactive.c |   41 +++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/drivers/cpufreq/cpufreq_interactive.c b/drivers/cpufreq/cpufreq_interactive.c
index 59e7779a..154f7bd 100644
--- a/drivers/cpufreq/cpufreq_interactive.c
+++ b/drivers/cpufreq/cpufreq_interactive.c
@@ -83,6 +83,13 @@ static unsigned long min_sample_time;
 #define DEFAULT_TIMER_RATE 20 * USEC_PER_MSEC
 static unsigned long timer_rate;
 
+/*
+ * Wait this long before raising speed above hispeed, by default a single
+ * timer interval.
+ */
+#define DEFAULT_ABOVE_HISPEED_DELAY DEFAULT_TIMER_RATE
+static unsigned long above_hispeed_delay_val;
+
 static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
 		unsigned int event);
 
@@ -174,6 +181,16 @@ static void cpufreq_interactive_timer(unsigned long data)
 
 			if (new_freq < hispeed_freq)
 				new_freq = hispeed_freq;
+
+			if (pcpu->target_freq == hispeed_freq &&
+			    new_freq > hispeed_freq &&
+			    pcpu->timer_run_time - pcpu->target_set_time
+			    < above_hispeed_delay_val) {
+				trace_cpufreq_interactive_notyet(data, cpu_load,
+								 pcpu->target_freq,
+								 new_freq);
+				goto rearm;
+			}
 		}
 	} else {
 		new_freq = pcpu->policy->max * cpu_load / 100;
@@ -515,6 +532,28 @@ static ssize_t store_min_sample_time(struct kobject *kobj,
 static struct global_attr min_sample_time_attr = __ATTR(min_sample_time, 0644,
 		show_min_sample_time, store_min_sample_time);
 
+static ssize_t show_above_hispeed_delay(struct kobject *kobj,
+					struct attribute *attr, char *buf)
+{
+	return sprintf(buf, "%lu\n", above_hispeed_delay_val);
+}
+
+static ssize_t store_above_hispeed_delay(struct kobject *kobj,
+					 struct attribute *attr,
+					 const char *buf, size_t count)
+{
+	int ret;
+	unsigned long val;
+
+	ret = strict_strtoul(buf, 0, &val);
+	if (ret < 0)
+		return ret;
+	above_hispeed_delay_val = val;
+	return count;
+}
+
+define_one_global_rw(above_hispeed_delay);
+
 static ssize_t show_timer_rate(struct kobject *kobj,
 			struct attribute *attr, char *buf)
 {
@@ -540,6 +579,7 @@ static struct global_attr timer_rate_attr = __ATTR(timer_rate, 0644,
 static struct attribute *interactive_attributes[] = {
 	&hispeed_freq_attr.attr,
 	&go_hispeed_load_attr.attr,
+	&above_hispeed_delay.attr,
 	&min_sample_time_attr.attr,
 	&timer_rate_attr.attr,
 	NULL,
@@ -660,6 +700,7 @@ static int __init cpufreq_interactive_init(void)
 
 	go_hispeed_load = DEFAULT_GO_HISPEED_LOAD;
 	min_sample_time = DEFAULT_MIN_SAMPLE_TIME;
+	above_hispeed_delay_val = DEFAULT_ABOVE_HISPEED_DELAY;
 	timer_rate = DEFAULT_TIMER_RATE;
 
 	/* Initalize per-cpu timers */
-- 
1.7.9.5

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