2013/4/10 Ingo Molnar <mi...@kernel.org>: > > * Frederic Weisbecker <fweis...@gmail.com> wrote: > >> Of course 128 bits ops are very expensive, so to help you evaluating the >> situation, this is going to happen on every call to task_cputime_adjusted() >> and >> thread_group_adjusted(), namely: > > It's really only expensive for divisions. Addition and multiplication should > be > straightforward and relatively low overhead, especially on 64-bit platforms.
Ok, well we still have one division in the scaling path. I'm mostly worried about the thread group exit that makes use of it through threadgroup_cputime_adjusted(). Not sure if we can avoid that. -- 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/
