netdev - Re: [RFC PATCH 0/2] netdev: Add tracepoint to network/driver interface

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <4BC2ADA5.9010203@jp.fujitsu.com>
Date:	Mon, 12 Apr 2010 14:20:37 +0900
From:	Koki Sanagi <sanagi.koki@...fujitsu.com>
To:	Neil Horman <nhorman@...driver.com>
CC:	netdev@...r.kernel.org, izumi.taku@...fujitsu.com,
	kaneshige.kenji@...fujitsu.com, davem@...emloft.net
Subject: Re: [RFC PATCH 0/2] netdev: Add tracepoint to network/driver interface

(2010/04/09 20:04), Neil Horman wrote:
> On Fri, Apr 09, 2010 at 04:37:53PM +0900, Koki Sanagi wrote:
>> These patches add tracepoints to network/driver interface.
>>
>> These tracepoints are helpful to investigate whether a packet passes or not.
>> For example, when Heart Beat is disconnected, that information is helpful
>> to investigate the cause is whether driver/device side or not.
>>
>> An output is below.
>>
>>    sshd-2443  [001] 68238.415621: netdev_start_xmit: dev=eth3 skbaddr=f3db5138 len=114
>> <idle>-0     [001] 68238.417058: netdev_receive_skb: dev=eth3 skbaddr=f3c81540 len=52
>> <idle>-0     [001] 68238.704363: netdev_receive_skb: dev=eth3 skbaddr=f3c81540 len=100
>>    sshd-2443  [001] 68238.705459: netdev_start_xmit: dev=eth3 skbaddr=f3db5138 len=114
>> <idle>-0     [001] 68238.706891: netdev_receive_skb: dev=eth3 skbaddr=f3c81540 len=52
>> <idle>-0     [001] 68238.878736: netdev_receive_skb: dev=eth3 skbaddr=f3c81540 len=100
>>    sshd-2443  [001] 68238.880361: netdev_start_xmit: dev=eth3 skbaddr=f3db5138 len=114
>>
>> As other use case I have, we can get throughput per interface with some sort of
>> perf scripts. I plan to create it.
>>
>> Thanks
>> Koki Sanagi
>>
> You can get a reasonable estimate of per-interface throughput using ethtool or
> even ifconfig in a script.  What are the tracepoints needed for that?  Don't get
> me wrong, I think these tracepoints could have some potential use thats not
> covered by other tools, I just don't see the above as a conclusive reason to add
> them.

Yeah, a script using ethtool or ifconfig can do same thing. But it must be poll
driven. By contrast this implement using tracepoint is event-driven.
It means that a record leaves on memory certainly whenever kernel crashes.
It is useful to investigate network record from dump.
This is superior to ethtool or ifconfig scripts.

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html