Messages in this thread | | | Date | Tue, 2 Apr 2013 16:30:48 +0200 | Subject | Re: [patch v6 03/21] sched: only count runnable avg on cfs_rq's nr_running | From | Vincent Guittot <> |
| |
On 30 March 2013 15:34, Alex Shi <alex.shi@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.shi@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.
Vincent > inc_nr_running(rq); > } > hrtick_update(rq); > -- > 1.7.12 >
| |