On Sun, Jun 29, 2014 at 12:59:41PM +0400, Kirill Tkhai wrote: > On 29.06.2014 12:36, Andreas Mohr wrote: > > I just noticed that there is a part touching rq->idle, > > and ISTR that idle task handling is "special" > > (after all that's the power management side of things). > > Specifically, rq->curr and rq->idle are distinct rq members > > (since they are distinct tasks AFAIK!), > > so there might now be some issues with task state tracking here > > (unless this cleanup happens to unify handling here anyway). > > Are you worrying about check_preempt_curr_idle()? I've looked > at check_preempt_curr() and found, we never call this function > in current scheduler logic.
Yeah - I should have included that hunk verbatim, sorry. > It's called only if just enqueued task is of the same class as > rq's current, but we can't have two idle class tasks enqueued > on the same rq. So, it's just a stub. We can do not worry > about this. That seems to be the case indeed in current implementation. Removing specific references from these sched_class parts (here: idle_task.c, rq->idle) where possible seems to be a good direction, since AFAIUI sched_class things are supposed to encode *behaviour*, where containing too many specific-member references is best avoided. I'd fathom that for the sched_curr() handler I'm still somewhat in favour of an extra non-inline wrapper though; it's just good minimal-dependency implementation. But more frequent topic partners might have more valuable input on this patch :) Thanks, Andreas -- 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/
