2013/4/10 Ingo Molnar <mingo@xxxxxxxxxx>: > > * Frederic Weisbecker <fweisbec@xxxxxxxxx> 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-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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