From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Perches <joe@perches.com>
Subject: Re: [PATCH net-next] net: implement tcp coalescing in
 tcp_queue_rcv()
Date: Wed, 02 May 2012 13:34:48 -0700
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Cc: David Miller <davem@davemloft.net>,
	Alexander Duyck <alexander.duyck@gmail.com>,
	Alexander Duyck <alexander.h.duyck@intel.com>,
	netdev <netdev@vger.kernel.org>,
	Neal Cardwell <ncardwell@google.com>,
	Tom Herbert <therbert@google.com>,
	Jeff Kirsher <jeffrey.t.kirsher@intel.com>,
	Michael Chan <mchan@broadcom.com>,
	Matt Carlson <mcarlson@broadcom.com>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	Ben Hutchings <bhutchings@solarflare.com>,
	Ilpo =?ISO-8859-1?Q?J=E4rvinen?= <ilpo.jarvinen@helsinki.fi>,
	Maciej =?UTF-8?Q?=C5=BBenczykowski?= <maze@google.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Wed, 2012-05-02 at 22:23 +0200, Eric Dumazet wrote:
> On Wed, 2012-05-02 at 13:11 -0700, Joe Perches wrote:
> > It might be useful to comment that this is/can be initialized to
> > false in tcp_try_coalesce via tcp_recv_queue.
> > Otherwise this looks like a possibly uninitialized test
> > of fragstolen.  Maybe there's a path where tail is null
> > in tcp_recv_queue and it's an uninitialized test anyway.
> 
> If tcp_queue_rcv() returns 1, fragstolen is initialized in
> tcp_try_coalesce().
> 
> If tcp_queue_rcv() returns 0, fragstolen content is undefined and we
> dont care.
> 
> If a compiler or static checker complains, its only their problem.

True, but it's code that's a bit fragile and
I think as such it could be improved for any
human reader by a descriptive comment.