On 04/02/2013 10:30 PM, Vincent Guittot wrote:
> On 30 March 2013 15:34, Alex Shi <alex....@intel.com> wrote:
>> Old function count the runnable avg on rq's nr_running even there is
>> only rt task in rq. That is incorrect, so correct it to cfs_rq's
>> nr_running.
>>
>> Signed-off-by: Alex Shi <alex....@intel.com>
>> ---
>> kernel/sched/fair.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
>> index 2881d42..026e959 100644
>> --- a/kernel/sched/fair.c
>> +++ b/kernel/sched/fair.c
>> @@ -2829,7 +2829,7 @@ enqueue_task_fair(struct rq *rq, struct task_struct
>> *p, int flags)
>> }
>>
>> if (!se) {
>> - update_rq_runnable_avg(rq, rq->nr_running);
>> + update_rq_runnable_avg(rq, rq->cfs.nr_running);
>
> A RT task that preempts your CFS task will be accounted in the
> runnable_avg fields. So whatever you do, RT task will impact your
> runnable_avg statistics. Instead of trying to get only CFS tasks, you
> should take into account all tasks activity in the rq.
Thanks for comments, Vincent!
Yes, I know some rt task time was counted into cfs, but now we have no
good idea to remove them clearly. So I just want to a bit more precise
cfs runnable load here.
On the other side, periodic LB balance on combined the cfs/rt load, but
removed the RT utilisation in cpu_power.
So, PJT, Peter, what's your idea of this point?
>
> Vincent
>> inc_nr_running(rq);
>> }
>> hrtick_update(rq);
>> --
>> 1.7.12
>>
--
Thanks Alex
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
