[PATCH] cpufreq-stats driver updates

Changes to the cpufreq stats driver:
* Changes the way P-state transition table looks in /sysfs providing more
  clear output
* Changes the time unit in the output from HZ to clock_t

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

1 files changed, 30 insertions, 17 deletions

diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index 2084593937c6..741b6b191e6a 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -19,6 +19,7 @@
 #include <linux/percpu.h>
 #include <linux/kobject.h>
 #include <linux/spinlock.h>
+#include <asm/cputime.h>
 
 static spinlock_t cpufreq_stats_lock;
 
@@ -29,20 +30,14 @@ static struct freq_attr _attr_##_name = {\
         .show = _show,\
 };
 
-static unsigned long
-delta_time(unsigned long old, unsigned long new)
-{
-        return (old > new) ? (old - new): (new + ~old + 1);
-}
-
 struct cpufreq_stats {
         unsigned int cpu;
         unsigned int total_trans;
-        unsigned long long last_time;
+        unsigned long long  last_time;
         unsigned int max_state;
         unsigned int state_num;
         unsigned int last_index;
-        unsigned long long *time_in_state;
+        cputime64_t *time_in_state;
         unsigned int *freq_table;
 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
         unsigned int *trans_table;
@@ -60,12 +55,16 @@ static int
 cpufreq_stats_update (unsigned int cpu)
 {
         struct cpufreq_stats *stat;
+        unsigned long long cur_time;
+
+        cur_time = get_jiffies_64();
         spin_lock(&cpufreq_stats_lock);
         stat = cpufreq_stats_table[cpu];
         if (stat->time_in_state)
-                stat->time_in_state[stat->last_index] +=
-                        delta_time(stat->last_time, jiffies);
-        stat->last_time = jiffies;
+                stat->time_in_state[stat->last_index] =
+                        cputime64_add(stat->time_in_state[stat->last_index],
+                                      cputime_sub(cur_time, stat->last_time));
+        stat->last_time = cur_time;
         spin_unlock(&cpufreq_stats_lock);
         return 0;
 }
@@ -90,8 +89,8 @@ show_time_in_state(struct cpufreq_policy *policy, char *buf)
                 return 0;
         cpufreq_stats_update(stat->cpu);
         for (i = 0; i < stat->state_num; i++) {
-                len += sprintf(buf + len, "%u %llu\n",
-                        stat->freq_table[i], stat->time_in_state[i]);
+                len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i], 
+                        (unsigned long long)cputime64_to_clock_t(stat->time_in_state[i]));
         }
         return len;
 }
@@ -107,16 +106,30 @@ show_trans_table(struct cpufreq_policy *policy, char *buf)
         if(!stat)
                 return 0;
         cpufreq_stats_update(stat->cpu);
+        len += snprintf(buf + len, PAGE_SIZE - len, "   From  :    To\n");
+        len += snprintf(buf + len, PAGE_SIZE - len, "         : ");
+        for (i = 0; i < stat->state_num; i++) {
+                if (len >= PAGE_SIZE)
+                        break;
+                len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
+                                stat->freq_table[i]);
+        }
+        if (len >= PAGE_SIZE)
+                return len;
+
+        len += snprintf(buf + len, PAGE_SIZE - len, "\n");
+
         for (i = 0; i < stat->state_num; i++) {
                 if (len >= PAGE_SIZE)
                         break;
-                len += snprintf(buf + len, PAGE_SIZE - len, "%9u:\t",
+
+                len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ",
                                 stat->freq_table[i]);
 
                 for (j = 0; j < stat->state_num; j++)   {
                         if (len >= PAGE_SIZE)
                                 break;
-                        len += snprintf(buf + len, PAGE_SIZE - len, "%u\t",
+                        len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
                                         stat->trans_table[i*stat->max_state+j]);
                 }
                 len += snprintf(buf + len, PAGE_SIZE - len, "\n");
@@ -197,7 +210,7 @@ cpufreq_stats_create_table (struct cpufreq_policy *policy,
                 count++;
         }
 
-        alloc_size = count * sizeof(int) + count * sizeof(long long);
+        alloc_size = count * sizeof(int) + count * sizeof(cputime64_t);
 
 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
         alloc_size += count * count * sizeof(int);
@@ -224,7 +237,7 @@ cpufreq_stats_create_table (struct cpufreq_policy *policy,
         }
         stat->state_num = j;
         spin_lock(&cpufreq_stats_lock);
-        stat->last_time = jiffies;
+        stat->last_time = get_jiffies_64();
         stat->last_index = freq_table_get_index(stat, policy->cur);
         spin_unlock(&cpufreq_stats_lock);
         cpufreq_cpu_put(data);