From 1cf05c27a34048f768a3d9ea1410a28e71763587 Mon Sep 17 00:00:00 2001 From: Venki Pallipadi Date: Wed, 20 Jun 2007 14:24:52 -0700 Subject: [PATCH] [PATCH] 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 Signed-off-by: Dave Jones Signed-off-by: Greg Kroah-Hartman Signed-off-by: Willy Tarreau --- drivers/cpufreq/cpufreq_ondemand.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 3bfaeb577624..1d11d13fb288 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -334,7 +334,7 @@ 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; @@ -380,7 +380,8 @@ 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) { -- 2.39.5