[PATCH] Resolve time unit thinko in ondemand/conservative govs
From: Pallipadi, Venkatesh
Date: Wed Nov 11 2009 - 19:50:37 EST
Dave,
Here is the fix for the bug reported on this thread. Please Apply. Looks to
be a stable candidate as well.
Thanks,
Venki
ondemand and conservative governors are messing up time units in the
code path where NO_HZ is not enabled and ignore_nice is set. The walltime
idletime stored is in jiffies and nice time calculation is happening in
microseconds.
The problem was reported and diagnosed by Alexander here.
http://marc.info/?l=linux-kernel&m=125752550404513&w=2
The patch below fixes this thinko.
Reported-by: Alexander Miller <Miller@xxxxxxxxxxxxxxxxxxxx>
Tested-by: Alexander Miller <Miller@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@xxxxxxxxx>
---
drivers/cpufreq/cpufreq_conservative.c | 4 ++--
drivers/cpufreq/cpufreq_ondemand.c | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index bc33ddc..c7b081b 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -116,9 +116,9 @@ static inline cputime64_t get_cpu_idle_time_jiffy(unsigned int cpu,
idle_time = cputime64_sub(cur_wall_time, busy_time);
if (wall)
- *wall = cur_wall_time;
+ *wall = (cputime64_t)jiffies_to_usecs(cur_wall_time);
- return idle_time;
+ return (cputime64_t)jiffies_to_usecs(idle_time);;
}
static inline cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall)
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index 071699d..4b34ade 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -133,9 +133,9 @@ static inline cputime64_t get_cpu_idle_time_jiffy(unsigned int cpu,
idle_time = cputime64_sub(cur_wall_time, busy_time);
if (wall)
- *wall = cur_wall_time;
+ *wall = (cputime64_t)jiffies_to_usecs(cur_wall_time);
- return idle_time;
+ return (cputime64_t)jiffies_to_usecs(idle_time);
}
static inline cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall)
--
1.6.0.6
--
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