From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1757214AbcH3IPg (ORCPT <rfc822;w@1wt.eu>);
        Tue, 30 Aug 2016 04:15:36 -0400
Received: from mail-it0-f50.google.com ([209.85.214.50]:34045 "EHLO
        mail-it0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1756689AbcH3IPd (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Tue, 30 Aug 2016 04:15:33 -0400
Subject: Re: [RFC PATCH 1/6] proc: Reduce cache miss in
 {snmp,netstat}_seq_show
To: Eric Dumazet <eric.dumazet@gmail.com>
References: <1472486640-1111-1-git-send-email-hejianet@gmail.com>
 <1472486640-1111-2-git-send-email-hejianet@gmail.com>
 <1472488885.14381.260.camel@edumazet-glaptop3.roam.corp.google.com>
Cc: netdev@vger.kernel.org, linux-sctp@vger.kernel.org,
        linux-kernel@vger.kernel.org, davem@davemloft.net,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        James Morris <jmorris@namei.org>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        Patrick McHardy <kaber@trash.net>, Vlad Yasevich <vyasevich@gmail.com>,
        Neil Horman <nhorman@tuxdriver.com>,
        Steffen Klassert <steffen.klassert@secunet.com>,
        Herbert Xu <herbert@gondor.apana.org.au>
From: hejianet <hejianet@gmail.com>
Message-ID: <0c4f4f45-ec27-d1d3-45f8-a7ed8a4ca667@gmail.com>
Date: Tue, 30 Aug 2016 16:15:36 +0800
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:45.0)
 Gecko/20100101 Thunderbird/45.2.0
MIME-Version: 1.0
In-Reply-To: <1472488885.14381.260.camel@edumazet-glaptop3.roam.corp.google.com>
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Hi Eric


On 8/30/16 12:41 AM, Eric Dumazet wrote:
> 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
Thanks, you are right. I misunderstand the comments of source codes.
Will resend it

B.R.
Jia
>
>
>
> .
>