On Wed, Aug 21, 2019 at 04:15:24PM +0100, Qais Yousef wrote: > On 08/16/19 22:12, Peng Liu wrote: > > Since sched_slice() is used in high frequency, > > small change should also make sense. > > > > Signed-off-by: Peng Liu <[email protected]> > > --- > > kernel/sched/fair.c | 11 ++++------- > > 1 file changed, 4 insertions(+), 7 deletions(-) > > > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > > index 1054d2cf6aaa..6ae2a507aac0 100644 > > --- a/kernel/sched/fair.c > > +++ b/kernel/sched/fair.c > > @@ -694,19 +694,16 @@ static u64 sched_slice(struct cfs_rq *cfs_rq, struct > > sched_entity *se) > > u64 slice = __sched_period(cfs_rq->nr_running + !se->on_rq); > > > > for_each_sched_entity(se) { > > - struct load_weight *load; > > struct load_weight lw; > > > > cfs_rq = cfs_rq_of(se); > > - load = &cfs_rq->load; > > + lw = cfs_rq->load; > > > > - if (unlikely(!se->on_rq)) { > > + if (unlikely(!se->on_rq)) > > lw = cfs_rq->load; > > > > - update_load_add(&lw, se->load.weight); > > - load = &lw; > > - } > > - slice = __calc_delta(slice, se->load.weight, load); > > + update_load_add(&lw, se->load.weight); > > + slice = __calc_delta(slice, se->load.weight, &lw); > > Unless I misread the diff, you changed the behavior. > > update_load_add() is only called if (unlikely(!se->on_rq)), but with your > change it is called unconditionally. And lw is set twice. > > I think what you intended is this?
So I'd really rather hold off on this; Rik is poking at getting rid of all of this hierarchical crud in one go.
