commit 93a51bfaf212c66d11e931c5d402b606874b8c14
author Joonwoo Park <joonwoop@codeaurora.org> Fri Jan 20 11:10:15 2017 -0800
committer Joonwoo Park <joonwoop@codeaurora.org> Tue May 09 11:22:46 2017 -0700
tree 6df020825e63772f767d097c7f5c110844093a1a
parent ebd02c22c8d7f99562cd96f67aa3a445183d7549

sched: WALT: fix potential overflow

Task demand and CPU util are in u64.

Change-Id: If7ec1623e723026d3346201122aab0303a6d2ba2
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>

kernel/sched/sched.h

diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 84ccbc3..216ee0e 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1734,14 +1734,14 @@
  */
 static inline unsigned long __cpu_util(int cpu, int delta)
 {
-	unsigned long util = cpu_rq(cpu)->cfs.avg.util_avg;
+	u64 util = cpu_rq(cpu)->cfs.avg.util_avg;
 	unsigned long capacity = capacity_orig_of(cpu);
 
 #ifdef CONFIG_SCHED_WALT
 	if (!walt_disabled && sysctl_sched_use_walt_cpu_util) {
-		util = cpu_rq(cpu)->hmp_stats.cumulative_runnable_avg <<
-		       SCHED_CAPACITY_SHIFT;
-		do_div(util, sched_ravg_window);
+		util = cpu_rq(cpu)->hmp_stats.cumulative_runnable_avg;
+		util = div64_u64(util,
+				 sched_ravg_window >> SCHED_CAPACITY_SHIFT);
 	}
 #endif
 	delta += util;
@@ -1765,13 +1765,14 @@
 static inline unsigned long
 cpu_util_freq(int cpu, struct sched_walt_cpu_load *walt_load)
 {
-	unsigned long util = cpu_rq(cpu)->cfs.avg.util_avg;
+	u64 util = cpu_rq(cpu)->cfs.avg.util_avg;
 	unsigned long capacity = capacity_orig_of(cpu);
 
 #ifdef CONFIG_SCHED_WALT
 	if (!walt_disabled && sysctl_sched_use_walt_cpu_util) {
-		util = cpu_rq(cpu)->prev_runnable_sum << SCHED_CAPACITY_SHIFT;
-		do_div(util, sched_ravg_window);
+		util = cpu_rq(cpu)->prev_runnable_sum;
+		util = div64_u64(util,
+				 sched_ravg_window >> SCHED_CAPACITY_SHIFT);
 
 		if (walt_load)
 			walt_load->prev_window_util = util;