Re: [RFC PATCH 1/6] proc: Reduce cache miss in {snmp,netstat}_seq_show

[Eric Dumazet]

On Tue, 2016-08-30 at 00:03 +0800, Jia He wrote:
> This patch exchanges the two loop for collecting the percpu statistics
> data. This can aggregate the data by going through all the items of each
> cpu sequentially. In snmp_seq_show, just use one buff copy to dislay the
> Udp and UdpLite data because they are the same.

This is obviously not true.

On my laptop it seems it handled no UdpLite frames, but got plenty of
Udp ones.

$ grep Udp /proc/net/snmp
Udp: InDatagrams NoPorts InErrors OutDatagrams RcvbufErrors SndbufErrors InCsumErrors
Udp: 1555889 108318 0 3740780 0 0 0
UdpLite: InDatagrams NoPorts InErrors OutDatagrams RcvbufErrors SndbufErrors InCsumErrors
UdpLite: 0 0 0 0 0 0 0