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Diffstat (limited to 'drivers/cpufreq')
-rw-r--r--drivers/cpufreq/cpufreq_ondemand.c30
1 files changed, 28 insertions, 2 deletions
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index bd444dc93cf2..ed472f8dfb72 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -73,6 +73,7 @@ enum {DBS_NORMAL_SAMPLE, DBS_SUB_SAMPLE};
struct cpu_dbs_info_s {
cputime64_t prev_cpu_idle;
+ cputime64_t prev_cpu_iowait;
cputime64_t prev_cpu_wall;
cputime64_t prev_cpu_nice;
struct cpufreq_policy *cur_policy;
@@ -148,6 +149,16 @@ static inline cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall)
return idle_time;
}
+static inline cputime64_t get_cpu_iowait_time(unsigned int cpu, cputime64_t *wall)
+{
+ u64 iowait_time = get_cpu_iowait_time_us(cpu, wall);
+
+ if (iowait_time == -1ULL)
+ return 0;
+
+ return iowait_time;
+}
+
/*
* Find right freq to be set now with powersave_bias on.
* Returns the freq_hi to be used right now and will set freq_hi_jiffies,
@@ -470,14 +481,15 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
for_each_cpu(j, policy->cpus) {
struct cpu_dbs_info_s *j_dbs_info;
- cputime64_t cur_wall_time, cur_idle_time;
- unsigned int idle_time, wall_time;
+ cputime64_t cur_wall_time, cur_idle_time, cur_iowait_time;
+ unsigned int idle_time, wall_time, iowait_time;
unsigned int load, load_freq;
int freq_avg;
j_dbs_info = &per_cpu(od_cpu_dbs_info, j);
cur_idle_time = get_cpu_idle_time(j, &cur_wall_time);
+ cur_iowait_time = get_cpu_iowait_time(j, &cur_wall_time);
wall_time = (unsigned int) cputime64_sub(cur_wall_time,
j_dbs_info->prev_cpu_wall);
@@ -487,6 +499,10 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
j_dbs_info->prev_cpu_idle);
j_dbs_info->prev_cpu_idle = cur_idle_time;
+ iowait_time = (unsigned int) cputime64_sub(cur_iowait_time,
+ j_dbs_info->prev_cpu_iowait);
+ j_dbs_info->prev_cpu_iowait = cur_iowait_time;
+
if (dbs_tuners_ins.ignore_nice) {
cputime64_t cur_nice;
unsigned long cur_nice_jiffies;
@@ -504,6 +520,16 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
idle_time += jiffies_to_usecs(cur_nice_jiffies);
}
+ /*
+ * For the purpose of ondemand, waiting for disk IO is an
+ * indication that you're performance critical, and not that
+ * the system is actually idle. So subtract the iowait time
+ * from the cpu idle time.
+ */
+
+ if (idle_time >= iowait_time)
+ idle_time -= iowait_time;
+
if (unlikely(!wall_time || wall_time < idle_time))
continue;