linux-kernel - [PATCH 30/70] cpufreq: interactive: remove load since last speed change

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Date:	Tue, 27 Oct 2015 18:30:18 +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 30/70] cpufreq: interactive: remove load since last speed change

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

The longer-term load since last speed change isn't terribly useful,
may delay recognition of dropping load, and would need forthcoming
changes to adjust load for changing CPU speeds.  Drop it.

Change-Id: Ic3cbb0542cc3484617031787e03ed9bdd632dec1
Signed-off-by: Todd Poynor <toddpoynor@...gle.com>
Signed-off-by: Bálint Czobor <czoborbalint@...il.com>
---
 drivers/cpufreq/cpufreq_interactive.c |   34 ++++-----------------------------
 1 file changed, 4 insertions(+), 30 deletions(-)

diff --git a/drivers/cpufreq/cpufreq_interactive.c b/drivers/cpufreq/cpufreq_interactive.c
index 6ea77a0..3d8e7b4 100644
--- a/drivers/cpufreq/cpufreq_interactive.c
+++ b/drivers/cpufreq/cpufreq_interactive.c
@@ -43,8 +43,6 @@ struct cpufreq_interactive_cpuinfo {
 	int timer_idlecancel;
 	u64 time_in_idle;
 	u64 time_in_idle_timestamp;
-	u64 target_set_time;
-	u64 target_set_time_in_idle;
 	struct cpufreq_policy *policy;
 	struct cpufreq_frequency_table *freq_table;
 	unsigned int target_freq;
@@ -238,7 +236,6 @@ static void cpufreq_interactive_timer(unsigned long data)
 	unsigned int delta_idle;
 	unsigned int delta_time;
 	int cpu_load;
-	int load_since_change;
 	struct cpufreq_interactive_cpuinfo *pcpu =
 		&per_cpu(cpuinfo, data);
 	u64 now_idle;
@@ -266,23 +263,6 @@ static void cpufreq_interactive_timer(unsigned long data)
 	else
 		cpu_load = 100 * (delta_time - delta_idle) / delta_time;
 
-	delta_idle = (unsigned int)(now_idle - pcpu->target_set_time_in_idle);
-	delta_time = (unsigned int)(now - pcpu->target_set_time);
-
-	if ((delta_time == 0) || (delta_idle > delta_time))
-		load_since_change = 0;
-	else
-		load_since_change =
-			100 * (delta_time - delta_idle) / delta_time;
-
-	/*
-	 * Choose greater of short-term load (since last idle timer
-	 * started or timer function re-armed itself) or long-term load
-	 * (since last frequency change).
-	 */
-	if (load_since_change > cpu_load)
-		cpu_load = load_since_change;
-
 	if ((cpu_load >= go_hispeed_load || boost_val) &&
 	    pcpu->target_freq < hispeed_freq)
 		new_freq = hispeed_freq;
@@ -335,8 +315,6 @@ static void cpufreq_interactive_timer(unsigned long data)
 
 	trace_cpufreq_interactive_target(data, cpu_load, pcpu->target_freq,
 					 pcpu->policy->cur, new_freq);
-	pcpu->target_set_time_in_idle = now_idle;
-	pcpu->target_set_time = now;
 
 	pcpu->target_freq = new_freq;
 	spin_lock_irqsave(&speedchange_cpumask_lock, flags);
@@ -500,9 +478,8 @@ static void cpufreq_interactive_boost(void)
 		if (pcpu->target_freq < hispeed_freq) {
 			pcpu->target_freq = hispeed_freq;
 			cpumask_set_cpu(i, &speedchange_cpumask);
-			pcpu->target_set_time_in_idle =
-				get_cpu_idle_time_us(i, &pcpu->target_set_time);
-			pcpu->hispeed_validate_time = pcpu->target_set_time;
+			pcpu->hispeed_validate_time =
+				ktime_to_us(ktime_get());
 			anyboost = 1;
 		}
 
@@ -815,14 +792,11 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
 			pcpu->policy = policy;
 			pcpu->target_freq = policy->cur;
 			pcpu->freq_table = freq_table;
-			pcpu->target_set_time_in_idle =
-				get_cpu_idle_time_us(j,
-					     &pcpu->target_set_time);
 			pcpu->floor_freq = pcpu->target_freq;
 			pcpu->floor_validate_time =
-				pcpu->target_set_time;
+				ktime_to_us(ktime_get());
 			pcpu->hispeed_validate_time =
-				pcpu->target_set_time;
+				pcpu->floor_validate_time;
 			pcpu->governor_enabled = 1;
 			smp_wmb();
 			pcpu->cpu_timer.expires =
-- 
1.7.9.5

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