[PATCH] cpufreq: fix conservative/ondemand behaviour with ignore_nice_load

[Alexander Miller]

Remove conversion of nice load to microseconds which caused addition
of times measured in different units and thus unreasonable behaviour
with both governors.                                                  

Signed-off-by: Alexander Miller <Miller@xxxxxxxxxxxxxxxxxxxx>
---
diff -uprN linux-2.6.git/drivers/cpufreq/cpufreq_conservative.c linux/drivers/cpufreq/cpufreq_conservative.c
--- linux-2.6.git/drivers/cpufreq/cpufreq_conservative.c	2009-10-10 15:56:58.010595257 +0200
+++ linux/drivers/cpufreq/cpufreq_conservative.c	2009-10-10 20:56:52.194598889 +0200
@@ -400,20 +400,10 @@ static void dbs_check_cpu(struct cpu_dbs
 		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,
+			idle_time += (unsigned int) 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))
diff -uprN linux-2.6.git/drivers/cpufreq/cpufreq_ondemand.c linux/drivers/cpufreq/cpufreq_ondemand.c
--- linux-2.6.git/drivers/cpufreq/cpufreq_ondemand.c	2009-10-10 16:00:40.380595816 +0200
+++ linux/drivers/cpufreq/cpufreq_ondemand.c	2009-10-10 20:56:52.195596654 +0200
@@ -488,20 +488,10 @@ static void dbs_check_cpu(struct cpu_dbs
 		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,
+			idle_time += (unsigned int) 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))
--
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