linux-kernel - [PATCH 2/3 linux-next] cpufreq: conservative: Fix the logic in frequency decrease checking

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Date:	Wed, 06 Mar 2013 00:06:40 +0200
From:	Stratos Karafotis <stratosk@...aphore.gr>
To:	"Rafael J. Wysocki" <rjw@...k.pl>
CC:	cpufreq@...r.kernel.org, linux-pm@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Viresh Kumar <viresh.kumar@...aro.org>
Subject: [PATCH 2/3 linux-next] cpufreq: conservative: Fix the logic in frequency
 decrease  checking

When we evaluate the CPU load for frequency decrease we have to compare
the load against down_threshold. There is no need to subtract 10 points
from down_threshold.

Instead, we have to use the default down_threshold or user's selection
unmodified.

Signed-off-by: Stratos Karafotis <stratosk@...aphore.gr>
---
 drivers/cpufreq/cpufreq_conservative.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index 1e3be56..08be431 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -92,12 +92,8 @@ static void cs_check_cpu(int cpu, unsigned int load)
 		return;
 	dbs_info->down_skip = 0;
 
-	/*
-	 * The optimal frequency is the frequency that is the lowest that can
-	 * support the current CPU usage without triggering the up policy. To be
-	 * safe, we focus 10 points under the threshold.
-	 */
-	if (load < (cs_tuners.down_threshold - 10)) {
+	/* Check for frequency decrease */
+	if (load < cs_tuners.down_threshold) {
 		freq_target = (cs_tuners.freq_step * policy->max) / 100;
 
 		dbs_info->requested_freq -= freq_target;
-- 
1.8.1.4

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