On Thu, 2013-03-28 at 16:58 +0900, Joonsoo Kim wrote: > Now checking that this cpu is appropriate to balance is embedded into > update_sg_lb_stats() and this checking has no direct relationship to > this > function. > > There is not enough reason to place this checking at > update_sg_lb_stats(), > except saving one iteration for sched_group_cpus.
Its only one iteration if there's only 2 groups, but there can be more than 2, take any desktop Intel i7, it will have 4-8 cores, each with HT; thus the CPU domain will have 4-8 groups. And note that local_group is always the first group of a domain, so we'd stop the balance at the first group and avoid touching the other 3-7, avoiding touching cachelines on 6-14 cpus. So this short-cut does make sense.. its not pretty, granted, but killing it doesn't seem right. -- 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/
