On Thu, Aug 15, 2013 at 11:23:53AM -0700, Paul Turner wrote: > On Thu, Aug 15, 2013 at 10:39 AM, Peter Zijlstra <pet...@infradead.org> wrote: > > On Tue, Aug 13, 2013 at 01:08:17AM -0700, Paul Turner wrote: > >> On Tue, Aug 13, 2013 at 12:38 AM, Peter Zijlstra <pet...@infradead.org> > >> wrote: > >> > On Tue, Aug 13, 2013 at 12:45:12PM +0800, Lei Wen wrote: > >> >> > Not quite right; I think you need busiest->cfs.h_nr_running. > >> >> > cfs.nr_running is the number of entries running in this 'group'. If > >> >> > you've got nested groups like: > >> >> > > >> >> > 'root' > >> >> > \ > >> >> > 'A' > >> >> > / \ > >> >> > t1 t2 > >> >> > > >> >> > root.nr_running := 1 'A', even though you've got multiple running > >> >> > tasks. > > > > One thing though; doesn't h_nr_running over count the number of tasks? > > That is, doesn't it count the runnable entities so the above case would > > give root.h_nr_running := 3, where we would only have 2 runnable tasks. > > > > Double check this and be careful when doing the conversion. > > This should be ok: it's accounted like rq->nr_running, not cfs_rq->nr_running. > Specifically: both only account tasks; group-entities do not contribute.
Ah, ok. I should have looked at the code I guess... :-) > The fact that this distinction exists, despite the very similar names > is unfortunate. > We could consider renaming to h_nr_{running_,}tasks for clarity. > The same applies to rq->nr_running, although that would involve more churn. Yah.. that would clarify, although longer variable names will also get us into more line-breaks I'm sure. Lets keep it as is. Maybe a comment somewhere would be enough. -- 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/