[PATCH 4/9] cpufreq: governor: Clean up load-related computations

[Rafael J. Wysocki]

From: Rafael J. Wysocki <rafael.j.wyso...@intel.com>

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.wyso...@intel.com>
---
 drivers/cpufreq/cpufreq_governor.c |   24 ++++++++++--------------
 1 file changed, 10 insertions(+), 14 deletions(-)

Index: linux-pm/drivers/cpufreq/cpufreq_governor.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/cpufreq_governor.c
+++ linux-pm/drivers/cpufreq/cpufreq_governor.c
@@ -186,16 +186,15 @@ void dbs_check_cpu(struct cpufreq_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];
@@ -571,13 +570,10 @@ static int cpufreq_governor_start(struct
                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 / j_cdbs->prev_cpu_wall;
 
                if (ignore_nice)
                        j_cdbs->prev_cpu_nice = 
kcpustat_cpu(j).cpustat[CPUTIME_NICE];