On Wed, 12 Mar 2014 16:23:48 +0400 Kirill Tkhai <[email protected]> wrote:
> > would there not need to be a check for p->migrate_disable ? > > push_rt_task() is not checking and so a high prio RT task > > preemting a low prio RT task in a migrate_disable() section > > would actually push it off this cpu ? atleast I did not > > find why that would not happen. > > Hi, Nicholas! > > p is not rq->curr, so its p->migrate_disable state is already updated and > it can't be pushed (nr_cpus_allowed == 1 and it's not pushable). > > (If I understand right, that you worry about this). > Correct. If p has migrate_disabled set and scheduled out, then when it gets scheduled out, its cpu affinity gets set to only the current cpu and nr_cpu_allowed to 1. No need to check here if p->migrate_disabled is set. -- Steve -- 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/
