* Dmitry Adamushko <[EMAIL PROTECTED]> wrote: > humm... I think, it'd be safer to have something like the following > change in place. > > The thing is that __pick_next_entity() must never be called when > first_fair(cfs_rq) == NULL. It wouldn't be a problem, should > 'run_node' be the very first field of 'struct sched_entity' (and it's > the second). > > The 'nr_running != 0' check is _not_ enough, due to the fact that > 'current' is not within the tree. Generic paths are ok (e.g. > schedule() as put_prev_task() is called previously)... I'm more > worried about e.g. migration_call() -> CPU_DEAD_FROZEN -> > migrate_dead_tasks()... if 'current' == rq->idle, no problems.. if > it's one of the SCHED_NORMAL tasks (or imagine, some other use-cases > in the future -- i.e. we should not make outer world dependent on > internal details of sched_fair class) -- it may be "Houston, we've got > a problem" case. > > it's +16 bytes to the ".text". Another variant is to make 'run_node' > the first data member of 'struct sched_entity' but an additional check > (se ! = NULL) is still needed in pick_next_entity().
looks good to me - and we already have something similar in sched_rt.c. I've added your patch to the queue. (Can i add your SoB line too?) Ingo - 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/