> > When selecting the cpu for a waking RT task, if curr is a non-RT > task which is bound only on this cpu, then we can give it a chance > to select a different cpu(definitely an idle cpu if existing) for > the RT task to avoid curr starving. > > Signed-off-by: pang.xunlei <[email protected]> > --- > kernel/sched/rt.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c > index da6922e..dc1f7f0 100644 > --- a/kernel/sched/rt.c > +++ b/kernel/sched/rt.c > @@ -1340,6 +1340,11 @@ select_task_rq_rt(struct task_struct *p, int cpu, int > sd_flag, int flags) > * runqueue. Otherwise simply start this RT task > * on its current runqueue. > * > + * If the current task on @p's runqueue is a non-RT task, > + * and this task is bound on current runqueue, then try to > + * see if we can wake this RT task up on a different runqueue, > + * we will definitely find an idle cpu if there is any. > + * > * We want to avoid overloading runqueues. If the woken > * task is a higher priority, then it will stay on this CPU > * and the lower prio task should be moved to another CPU. > @@ -1356,9 +1361,8 @@ select_task_rq_rt(struct task_struct *p, int cpu, int > sd_flag, int flags) > * This test is optimistic, if we get it wrong the load-balancer > * will have to sort it out. > */ > - if (curr && unlikely(rt_task(curr)) && > - (curr->nr_cpus_allowed < 2 || > - curr->prio <= p->prio)) { > + if (curr && unlikely(curr->nr_cpus_allowed < 2 || > + curr->prio <= p->prio)) {
Nack, it is no meaning to compare apple against orange. Hillf > int target = find_lowest_rq(p); > > if (target != -1) > -- > 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
