On Wed, Feb 15, 2017 at 10:47:49AM +0000, Juri Lelli wrote: > [+Steve, Luca] > > Hi, > > On 15/02/17 14:11, Byungchul Park wrote: > > Once pick_next_pushable_dl_task(rq) return a task, it guarantees that > > the task's cpu is rq->cpu, so task_cpu(next_task) is always rq->cpu if > > task == next_task. Remove a redundant condition and make code simpler. > > > > Signed-off-by: Byungchul Park <[email protected]> > > --- > > kernel/sched/deadline.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c > > index 27737f3..ad8d577 100644 > > --- a/kernel/sched/deadline.c > > +++ b/kernel/sched/deadline.c > > @@ -1483,7 +1483,7 @@ static int push_dl_task(struct rq *rq) > > * then possible that next_task has migrated. > > */ > > task = pick_next_pushable_dl_task(rq); > > - if (task_cpu(next_task) == rq->cpu && task == next_task) { > > + if (task == next_task) { > > Seems a sensible optimization to me. Actually, we are doing the same for > rt.c; Steve, Peter, do you think we should optimize that as well? >
If correct (and I've not spend brain cycles on that) yes. We should keep this push-pull muck synced between rt and deadline as much as possible.
