On 07/10/14 13:13, Vincent Guittot wrote:
Add new statistics which reflect the average time a task is running on the CPU and the sum of these running time of the tasks on a runqueue. The latter is named utilization_avg_contrib.
This patch is based on the usage metric that was proposed in the 1st versions of the per-entity load tracking patchset by Paul Turner pjt@google.com but that has be removed afterward. This version differs from the original one in the sense that it's not linked to task_group.
The rq's utilization_avg_contrib will be used to check if a rq is overloaded or not instead of trying to compute how many task a group of CPUs can handle
Rename runnable_avg_period into avg_period as it is now used with both runnable_avg_sum and running_avg_sum
Add some descriptions of the variables to explain their differences
Signed-off-by: Vincent Guittot vincent.guittot@linaro.org
include/linux/sched.h | 21 +++++++++++++--- kernel/sched/debug.c | 9 ++++--- kernel/sched/fair.c | 70 +++++++++++++++++++++++++++++++++++++++------------ kernel/sched/sched.h | 8 +++++- 4 files changed, 84 insertions(+), 24 deletions(-)
[...]
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 9075dee..d6de526 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -678,8 +678,8 @@ void init_task_runnable_average(struct task_struct *p)
p->se.avg.decay_count = 0; slice = sched_slice(task_cfs_rq(p), &p->se) >> 10;
p->se.avg.runnable_avg_sum = slice;p->se.avg.runnable_avg_period = slice;
p->se.avg.runnable_avg_sum = p->se.avg.running_avg_sum = slice;p->se.avg.avg_period = slice; __update_task_entity_contrib(&p->se);
Didn't you miss a call to __update_task_entity_utilization here?
Another thing from the naming perspective: You use the term 'utilization' for 'load' (e.g. existing __update_entity_load_avg_contrib versus new __update_entity_utilization_avg_contrib) but for the __update_task_entity_contrib function, you use the term 'utilization' for 'contrib'. IMHO, kind of hard to grasp.
} #else @@ -1548,7 +1548,7 @@ static u64 numa_get_avg_runtime(struct task_struct *p, u64 *period) *period = now - p->last_task_numa_placement; } else { delta = p->se.avg.runnable_avg_sum;
*period = p->se.avg.runnable_avg_period;
*period = p->se.avg.avg_period; } p->last_sum_exec_runtime = runtime;