cpufreq: interactive: set floor for boosted speed

Allow speed to drop to flooor frequency but not below, don't pin
to speed at last boost.

Change-Id: I0147c2b7a2e61ba16820605af6baaf09570be787
Signed-off-by: Todd Poynor <toddpoynor@google.com>

diff --git a/drivers/cpufreq/cpufreq_interactive.c b/drivers/cpufreq/cpufreq_interactive.c
index 07b7cafaffddbef17c7b1c1a16a9ed8aa6b6ef01..fcd5b1d81fb6e13d7dfe51f4a92189b22113dd67 100644 (file)
--- a/drivers/cpufreq/cpufreq_interactive.c
+++ b/drivers/cpufreq/cpufreq_interactive.c
@@ -47,10 +47,11 @@ struct cpufreq_interactive_cpuinfo {
        int idling;
        u64 target_set_time;
        u64 target_set_time_in_idle;
-       u64 target_validate_time;
        struct cpufreq_policy *policy;
        struct cpufreq_frequency_table *freq_table;
        unsigned int target_freq;
+       unsigned int floor_freq;
+       u64 floor_validate_time;
        int governor_enabled;
 };
 
@@ -228,10 +229,10 @@ static void cpufreq_interactive_timer(unsigned long data)
        new_freq = pcpu->freq_table[index].frequency;
 
        /*
-        * Do not scale down unless we have been at this frequency for the
-        * minimum sample time since last validated.
+        * Do not scale below floor_freq unless we have been at or above the
+        * floor frequency for the minimum sample time since last validated.
         */
-       if (new_freq < pcpu->target_freq) {
+       if (new_freq < pcpu->floor_freq) {
                if (pcpu->timer_run_time - pcpu->target_validate_time
                    < min_sample_time) {
                        trace_cpufreq_interactive_notyet(data, cpu_load,
@@ -240,7 +241,8 @@ static void cpufreq_interactive_timer(unsigned long data)
                }
        }
 
-       pcpu->target_validate_time = pcpu->timer_run_time;
+       pcpu->floor_freq = new_freq;
+       pcpu->floor_validate_time = pcpu->timer_run_time;
 
        if (pcpu->target_freq == new_freq) {
                trace_cpufreq_interactive_already(data, cpu_load,
@@ -508,12 +510,12 @@ static void cpufreq_interactive_boost(void)
                }
 
                /*
-                * Refresh time at which current (possibly being
-                * boosted) speed last validated (reset timer for
-                * allowing speed to drop).
+                * Set floor freq and (re)start timer for when last
+                * validated.
                 */
 
-               pcpu->target_validate_time = ktime_to_us(ktime_get());
+               pcpu->floor_freq = hispeed_freq;
+               pcpu->floor_validate_time = ktime_to_us(ktime_get());
        }
 
        spin_unlock_irqrestore(&up_cpumask_lock, flags);
@@ -811,7 +813,8 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
                        pcpu->target_set_time_in_idle =
                                get_cpu_idle_time_us(j,
                                             &pcpu->target_set_time);
-                       pcpu->target_validate_time =
+                       pcpu->floor_freq = pcpu->target_freq;
+                       pcpu->floor_validate_time =
                                pcpu->target_set_time;
                        pcpu->governor_enabled = 1;
                        smp_wmb();