From: Minsung Kim <ms925....@samsung.com>
Check for idle time delta less than elapsed time delta, avoid
underflow computing active time.
Change-Id: I3e4c6ef1ad794eec49ed379c0c50fa727fd6ad28
Signed-off-by: Minsung Kim <ms925....@samsung.com>
Signed-off-by: Bálint Czobor <czoborbal...@gmail.com>
---
drivers/cpufreq/cpufreq_interactive.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/cpufreq/cpufreq_interactive.c
b/drivers/cpufreq/cpufreq_interactive.c
index b4d12b2..7303f50 100644
--- a/drivers/cpufreq/cpufreq_interactive.c
+++ b/drivers/cpufreq/cpufreq_interactive.c
@@ -325,7 +325,12 @@ static u64 update_load(int cpu)
now_idle = get_cpu_idle_time(cpu, &now);
delta_idle = (unsigned int)(now_idle - pcpu->time_in_idle);
delta_time = (unsigned int)(now - pcpu->time_in_idle_timestamp);
- active_time = delta_time - delta_idle;
+
+ if (delta_time <= delta_idle)
+ active_time = 0;
+ else
+ active_time = delta_time - delta_idle;
+
pcpu->cputime_speedadj += active_time * pcpu->policy->cur;
pcpu->time_in_idle = now_idle;
--
1.7.9.5
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