[CPUFREQ] Make ignore_nice_load setting of ondemand work as expected.

ondemand micro-accounting of idle time changes broke ignore_nice_load
sysfs setting due to a thinko in the code.

The bug entry:
http://bugzilla.kernel.org/show_bug.cgi?id=12310

Reported-by: Jim Bray <jimsantelmo@gmail.com>

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>

1 files changed, 25 insertions, 22 deletions

diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index 6a2b036c9389..6f45b1658a67 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -117,11 +117,7 @@ static inline cputime64_t get_cpu_idle_time_jiffy(unsigned int cpu,
         busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.irq);
         busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.softirq);
         busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.steal);
-
-        if (!dbs_tuners_ins.ignore_nice) {
-                busy_time = cputime64_add(busy_time,
-                                kstat_cpu(cpu).cpustat.nice);
-        }
+        busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.nice);
 
         idle_time = cputime64_sub(cur_wall_time, busy_time);
         if (wall)
@@ -137,23 +133,6 @@ static inline cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall)
         if (idle_time == -1ULL)
                 return get_cpu_idle_time_jiffy(cpu, wall);
 
-        if (dbs_tuners_ins.ignore_nice) {
-                cputime64_t cur_nice;
-                unsigned long cur_nice_jiffies;
-                struct cpu_dbs_info_s *dbs_info;
-
-                dbs_info = &per_cpu(cpu_dbs_info, cpu);
-                cur_nice = cputime64_sub(kstat_cpu(cpu).cpustat.nice,
-                                         dbs_info->prev_cpu_nice);
-                /*
-                 * Assumption: nice time between sampling periods will be
-                 * less than 2^32 jiffies for 32 bit sys
-                 */
-                cur_nice_jiffies = (unsigned long)
-                                        cputime64_to_jiffies64(cur_nice);
-                dbs_info->prev_cpu_nice = kstat_cpu(cpu).cpustat.nice;
-                return idle_time + jiffies_to_usecs(cur_nice_jiffies);
-        }
         return idle_time;
 }
 
@@ -319,6 +298,9 @@ static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy,
                 dbs_info = &per_cpu(cpu_dbs_info, j);
                 dbs_info->prev_cpu_idle = get_cpu_idle_time(j,
                                                 &dbs_info->prev_cpu_wall);
+                if (dbs_tuners_ins.ignore_nice)
+                        dbs_info->prev_cpu_nice = kstat_cpu(j).cpustat.nice;
+
         }
         mutex_unlock(&dbs_mutex);
 
@@ -419,6 +401,23 @@ 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;
 
+                if (dbs_tuners_ins.ignore_nice) {
+                        cputime64_t cur_nice;
+                        unsigned long cur_nice_jiffies;
+
+                        cur_nice = cputime64_sub(kstat_cpu(j).cpustat.nice,
+                                         j_dbs_info->prev_cpu_nice);
+                        /*
+                         * Assumption: nice time between sampling periods will
+                         * be less than 2^32 jiffies for 32 bit sys
+                         */
+                        cur_nice_jiffies = (unsigned long)
+                                        cputime64_to_jiffies64(cur_nice);
+
+                        j_dbs_info->prev_cpu_nice = kstat_cpu(j).cpustat.nice;
+                        idle_time += jiffies_to_usecs(cur_nice_jiffies);
+                }
+
                 if (unlikely(!wall_time || wall_time < idle_time))
                         continue;
 
@@ -575,6 +574,10 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
 
                         j_dbs_info->prev_cpu_idle = get_cpu_idle_time(j,
                                                 &j_dbs_info->prev_cpu_wall);
+                        if (dbs_tuners_ins.ignore_nice) {
+                                j_dbs_info->prev_cpu_nice =
+                                                kstat_cpu(j).cpustat.nice;
+                        }
                 }
                 this_dbs_info->cpu = cpu;
                 /*