[RFCv3 PATCH 27/48] sched: Relocated get_cpu_usage()

From: Morten Rasmussen
Date: Wed Feb 04 2015 - 13:37:53 EST


Move get_cpu_usage() to an earlier position in fair.c.

cc: Ingo Molnar <mingo@xxxxxxxxxx>
cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>

Signed-off-by: Morten Rasmussen <morten.rasmussen@xxxxxxx>
---
kernel/sched/fair.c | 56 ++++++++++++++++++++++++++---------------------------
1 file changed, 28 insertions(+), 28 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 70acb4c..071310a 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4575,6 +4575,34 @@ static unsigned long capacity_curr_of(int cpu)
>> SCHED_CAPACITY_SHIFT;
}

+/*
+ * get_cpu_usage returns the amount of capacity of a CPU that is used by CFS
+ * tasks. The unit of the return value must capacity so we can compare the
+ * usage with the capacity of the CPU that is available for CFS task (ie
+ * cpu_capacity).
+ * cfs.utilization_load_avg is the sum of running time of runnable tasks on a
+ * CPU. It represents the amount of utilization of a CPU in the range
+ * [0..SCHED_LOAD_SCALE]. The usage of a CPU can't be higher than the full
+ * capacity of the CPU because it's about the running time on this CPU.
+ * Nevertheless, cfs.utilization_load_avg can be higher than SCHED_LOAD_SCALE
+ * because of unfortunate rounding in avg_period and running_load_avg or just
+ * after migrating tasks until the average stabilizes with the new running
+ * time. So we need to check that the usage stays into the range
+ * [0..cpu_capacity_orig] and cap if necessary.
+ * Without capping the usage, a group could be seen as overloaded (CPU0 usage
+ * at 121% + CPU1 usage at 80%) whereas CPU1 has 20% of available capacity/
+ */
+static int get_cpu_usage(int cpu)
+{
+ unsigned long usage = cpu_rq(cpu)->cfs.utilization_load_avg;
+ unsigned long blocked = cpu_rq(cpu)->cfs.utilization_blocked_avg;
+
+ if (usage + blocked >= SCHED_LOAD_SCALE)
+ return capacity_orig_of(cpu);
+
+ return usage + blocked;
+}
+
static inline bool energy_aware(void)
{
return sched_feat(ENERGY_AWARE);
@@ -4827,34 +4855,6 @@ static int select_idle_sibling(struct task_struct *p, int target)
return target;
}
/*
- * get_cpu_usage returns the amount of capacity of a CPU that is used by CFS
- * tasks. The unit of the return value must capacity so we can compare the
- * usage with the capacity of the CPU that is available for CFS task (ie
- * cpu_capacity).
- * cfs.utilization_load_avg is the sum of running time of runnable tasks on a
- * CPU. It represents the amount of utilization of a CPU in the range
- * [0..SCHED_LOAD_SCALE]. The usage of a CPU can't be higher than the full
- * capacity of the CPU because it's about the running time on this CPU.
- * Nevertheless, cfs.utilization_load_avg can be higher than SCHED_LOAD_SCALE
- * because of unfortunate rounding in avg_period and running_load_avg or just
- * after migrating tasks until the average stabilizes with the new running
- * time. So we need to check that the usage stays into the range
- * [0..cpu_capacity_orig] and cap if necessary.
- * Without capping the usage, a group could be seen as overloaded (CPU0 usage
- * at 121% + CPU1 usage at 80%) whereas CPU1 has 20% of available capacity/
- */
-static int get_cpu_usage(int cpu)
-{
- unsigned long usage = cpu_rq(cpu)->cfs.utilization_load_avg;
- unsigned long blocked = cpu_rq(cpu)->cfs.utilization_blocked_avg;
-
- if (usage + blocked >= SCHED_LOAD_SCALE)
- return capacity_orig_of(cpu);
-
- return usage + blocked;
-}
-
-/*
* select_task_rq_fair: Select target runqueue for the waking task in domains
* that have the 'sd_flag' flag set. In practice, this is SD_BALANCE_WAKE,
* SD_BALANCE_FORK, or SD_BALANCE_EXEC.
--
1.9.1

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