Re: [tip:sched/core] sched: Lower chances of cputime scaling overflow

From: Ingo Molnar
Date: Wed Apr 10 2013 - 08:51:20 EST



* 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.

Thanks,

Ingo
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