netdev - Re: [PATCH net-next] TCP: make seq # error messages more readable

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Message-ID: <3f635da3-45ac-da42-1db1-485fb1d5ecd4@infradead.org>
Date:   Fri, 13 Jul 2018 09:48:41 -0700
From:   Randy Dunlap <rdunlap@...radead.org>
To:     Eric Dumazet <eric.dumazet@...il.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        David Miller <davem@...emloft.net>,
        Eric Dumazet <edumazet@...gle.com>
Cc:     積丹尼 Dan Jacobson <jidanni@...anni.org>
Subject: Re: [PATCH net-next] TCP: make seq # error messages more readable

On 07/13/2018 06:38 AM, Eric Dumazet wrote:
> 
> 
> On 07/12/2018 05:48 PM, Randy Dunlap wrote:
>> From: Randy Dunlap <rdunlap@...radead.org>
>>
>> Attempt to make cryptic TCP seq number error messages clearer by
>> (1) adding the function name, (2) identifying the errors as "seq # bug",
>> and (3) grouping the field identifiers and values by separating them
>> with commas.
>>
>> E.g., the following message is changed from:
>>
>> recvmsg bug 2: copied 73BCB6CD seq 70F17CBE rcvnxt 73BCB9AA fl 0
>> WARNING: CPU: 2 PID: 1501 at /linux/net/ipv4/tcp.c:1881 tcp_recvmsg+0x649/0xb90
>>
>> to:
>>
>> tcp_recvmsg: TCP recvmsg seq # bug 2: copied 73BCB6CD, seq 70F17CBE, rcvnxt 73BCB9AA, fl 0
>> WARNING: CPU: 2 PID: 1501 at /linux/net/ipv4/tcp.c:2011 tcp_recvmsg+0x694/0xba0
>>
> 
> Hi Randy
> 
> It is not clear what this patch improves.
> Do we really to mention tcp twice ?

I will gladly drop the __func__: string.  Doing so would change this:

recvmsg bug 2: copied 73BCB6CD seq 70F17CBE rcvnxt 73BCB9AA fl 0

to:

TCP recvmsg seq # bug 2: copied 73BCB6CD, seq 70F17CBE, rcvnxt 73BCB9AA, fl 0


The (new) message identifies that it is TCP and that it is a sequence # bug.
Both of those are helpful in my view, whereas the original message isn't
helpful at all.


> 
> Thanks.


-- 
~Randy