On Thu, 2015-07-02 at 09:35 -0700, John Fastabend wrote: > > + if (gact->tcf_tm.lastuse != jiffies) > > + gact->tcf_tm.lastuse = jiffies; > > I'm missing the point of the if block. Is that really good enough > for the 32bit system case? I would have expected some wrapper to > handle it here something like u64_stats_() maybe _u64_jiffies(). Maybe > after a coffee I'll make sense of it. >
Point is to not dirty cache line for every packet ? Doing the test means we attempt dirtying only ~HZ times per second, which really matters to handle millions of packets per second. My tests show a good enough performance, not sure we want a percpu thing for this lastuse field. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
