[PATCH 22/70] cpufreq: interactive: run at fraction of hispeed_freq when load is low

From: BÃlint Czobor
Date: Tue Oct 27 2015 - 13:32:26 EST

From: Todd Poynor <toddpoynor@xxxxxxxxxx>

When load is below go_hispeed_load, apply the percentage of CPU load to
a max frequency of hispeed_freq instead of the max speed. This avoids
jumping too quickly to hispeed_freq when it is a relatively low
percentage of max speed. This also allows go_hispeed_load to be set to
a high percentage relative to hispeed_freq (as a percentage of max speed,
again useful when hispeed_freq is a low fraction of max speed), to cap
larger loads at hispeed_freq. For example, a load of 60% will typically
move to 60% of hispeed_freq, not 60% of max speed. This causes the
governor to apply two different speed caps, depending on whether load is
below or above go_hispeed_load.

Also fix the type of hispeed_freq, which was u64, to match other
speed data types (and avoid overhead and allow division).

Change-Id: Ie2d0668be161c074aaad77db2037505431457b3a
Signed-off-by: Todd Poynor <toddpoynor@xxxxxxxxxx>
Signed-off-by: BÃlint Czobor <czoborbalint@xxxxxxxxx>
drivers/cpufreq/cpufreq_interactive.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/cpufreq/cpufreq_interactive.c b/drivers/cpufreq/cpufreq_interactive.c
index f85fbbd..16bd23b 100644
--- a/drivers/cpufreq/cpufreq_interactive.c
+++ b/drivers/cpufreq/cpufreq_interactive.c
@@ -63,7 +63,7 @@ static cpumask_t speedchange_cpumask;
static spinlock_t speedchange_cpumask_lock;

/* Hi speed to bump to from lo speed when load burst (default max) */
-static u64 hispeed_freq;
+static unsigned int hispeed_freq;

/* Go to hi speed when CPU load at or above this value. */
@@ -198,7 +198,7 @@ static void cpufreq_interactive_timer(unsigned long data)
} else {
- new_freq = pcpu->policy->max * cpu_load / 100;
+ new_freq = hispeed_freq * cpu_load / 100;

if (new_freq <= hispeed_freq)
@@ -465,7 +465,7 @@ static void cpufreq_interactive_boost(void)
static ssize_t show_hispeed_freq(struct kobject *kobj,
struct attribute *attr, char *buf)
- return sprintf(buf, "%llu\n", hispeed_freq);
+ return sprintf(buf, "%u\n", hispeed_freq);

static ssize_t store_hispeed_freq(struct kobject *kobj,
@@ -473,9 +473,9 @@ static ssize_t store_hispeed_freq(struct kobject *kobj,
size_t count)
int ret;
- u64 val;
+ long unsigned int val;

- ret = strict_strtoull(buf, 0, &val);
+ ret = strict_strtoul(buf, 0, &val);
if (ret < 0)
return ret;
hispeed_freq = val;

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