uid_cputime: fix cputime overflow

Converting cputime_t to usec caused overflow when the value is greater
than 1 hour. Use msec and convert to unsigned long long to support bigger
range.

Bug: 22461683

Change-Id: I853fe3e8e7dbf0d3e2cc5c6f9688a5a6e1f1fb3e
Signed-off-by: Jin Qian <jinqian@google.com>

drivers/misc/uid_cputime.c

@@ -119,9 +119,11 @@ static int uid_stat_show(struct seq_file *m, void *v)
 							uid_entry->active_stime;
 		unsigned long long total_power = uid_entry->power +
 							uid_entry->active_power;
-		seq_printf(m, "%d: %u %u %llu\n", uid_entry->uid,
-						cputime_to_usecs(total_utime),
-						cputime_to_usecs(total_stime),
+		seq_printf(m, "%d: %llu %llu %llu\n", uid_entry->uid,
+			(unsigned long long)jiffies_to_msecs(
+				cputime_to_jiffies(total_utime)) * USEC_PER_MSEC,
+			(unsigned long long)jiffies_to_msecs(
+				cputime_to_jiffies(total_stime)) * USEC_PER_MSEC,
 			total_power);
 	}