Vincent Guittot <vincent.guit...@linaro.org> writes: > With the current implementation, the load average statistics of a sched entity > change according to other activity on the CPU even if this activity is done > between the running window of the sched entity and have no influence on the > running duration of the task. > > When a task wakes up on the same CPU, we currently update last_runnable_update > with the return of __synchronize_entity_decay without updating the > runnable_avg_sum and runnable_avg_period accordingly. In fact, we have to sync > the load_contrib of the se with the rq's blocked_load_contrib before removing > it from the latter (with __synchronize_entity_decay) but we must keep > last_runnable_update unchanged for updating runnable_avg_sum/period during the > next update_entity_load_avg.
... Gah, that's correct, we had this right the first time. Could you do this as a full revert of 282cf499f03ec1754b6c8c945c9674b02631fb0f (ie remove the now inaccurate comment, or maybe replace it with a correct one). > > Signed-off-by: Vincent Guittot <vincent.guit...@linaro.org> > --- > kernel/sched/fair.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index e64b079..5b0ef90 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -2370,8 +2370,7 @@ static inline void enqueue_entity_load_avg(struct > cfs_rq *cfs_rq, > * would have made count negative); we must be careful to avoid > * double-accounting blocked time after synchronizing decays. > */ > - se->avg.last_runnable_update += __synchronize_entity_decay(se) > - << 20; > + __synchronize_entity_decay(se); > } > > /* migrated tasks did not contribute to our blocked load */ -- 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/
