cpufreq: governor: Clean up load-related computations
authorRafael J. Wysocki <rafael.j.wysocki@intel.com>
Mon, 15 Feb 2016 23:58:47 +0000 (00:58 +0100)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Wed, 9 Mar 2016 13:41:03 +0000 (14:41 +0100)
Clean up some load-related computations in dbs_check_cpu() and
cpufreq_governor_start() to get rid of unnecessary operations and
type casts and make the code easier to read.

No functional changes.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
drivers/cpufreq/cpufreq_governor.c

index c5469701a3ef8886e8a11b51d5c6e14d9af7ef9b..1f580cb62902dcf11a6f15cecc0e8332ba47a052 100644 (file)
@@ -186,16 +186,15 @@ void dbs_check_cpu(struct cpufreq_policy *policy)
                        io_busy = od_tuners->io_is_busy;
                cur_idle_time = get_cpu_idle_time(j, &cur_wall_time, io_busy);
 
-               wall_time = (unsigned int)
-                       (cur_wall_time - j_cdbs->prev_cpu_wall);
+               wall_time = cur_wall_time - j_cdbs->prev_cpu_wall;
                j_cdbs->prev_cpu_wall = cur_wall_time;
 
-               if (cur_idle_time < j_cdbs->prev_cpu_idle)
-                       cur_idle_time = j_cdbs->prev_cpu_idle;
-
-               idle_time = (unsigned int)
-                       (cur_idle_time - j_cdbs->prev_cpu_idle);
-               j_cdbs->prev_cpu_idle = cur_idle_time;
+               if (cur_idle_time <= j_cdbs->prev_cpu_idle) {
+                       idle_time = 0;
+               } else {
+                       idle_time = cur_idle_time - j_cdbs->prev_cpu_idle;
+                       j_cdbs->prev_cpu_idle = cur_idle_time;
+               }
 
                if (ignore_nice) {
                        u64 cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE];
@@ -562,13 +561,10 @@ static int cpufreq_governor_start(struct cpufreq_policy *policy)
                struct cpu_dbs_info *j_cdbs = gov->get_cpu_cdbs(j);
                unsigned int prev_load;
 
-               j_cdbs->prev_cpu_idle =
-                       get_cpu_idle_time(j, &j_cdbs->prev_cpu_wall, io_busy);
+               j_cdbs->prev_cpu_idle = get_cpu_idle_time(j, &j_cdbs->prev_cpu_wall, io_busy);
 
-               prev_load = (unsigned int)(j_cdbs->prev_cpu_wall -
-                                           j_cdbs->prev_cpu_idle);
-               j_cdbs->prev_load = 100 * prev_load /
-                                   (unsigned int)j_cdbs->prev_cpu_wall;
+               prev_load = j_cdbs->prev_cpu_wall - j_cdbs->prev_cpu_idle;
+               j_cdbs->prev_load = 100 * prev_load / (unsigned int)j_cdbs->prev_cpu_wall;
 
                if (ignore_nice)
                        j_cdbs->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE];