[CPUFREQ] ondemand: add a check to avoid negative load calculation

Due to rounding and inexact jiffy accounting, idle_ticks can sometimes
be higher than total_ticks. Make sure those cases are handled as
zero load case.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
This commit is contained in:
Venki Pallipadi 2007-06-20 14:24:52 -07:00 committed by Dave Jones
parent c7f652e048
commit 0af99b13c9

View file

@ -325,7 +325,7 @@ static struct attribute_group dbs_attr_group = {
static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
{
unsigned int idle_ticks, total_ticks;
unsigned int load;
unsigned int load = 0;
cputime64_t cur_jiffies;
struct cpufreq_policy *policy;
@ -370,7 +370,8 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
if (tmp_idle_ticks < idle_ticks)
idle_ticks = tmp_idle_ticks;
}
load = (100 * (total_ticks - idle_ticks)) / total_ticks;
if (likely(total_ticks > idle_ticks))
load = (100 * (total_ticks - idle_ticks)) / total_ticks;
/* Check for frequency increase */
if (load > dbs_tuners_ins.up_threshold) {