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Date: Mon, 5 Jan 2015 22:41:52 +0100 (CET)
From: Julia Lawall <julia.lawall@lip6.fr>
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To: SF Markus Elfring <elfring@users.sourceforge.net>
cc: Dan Carpenter <dan.carpenter@oracle.com>,
        Eric Van Hensbergen <ericvh@gmail.com>,
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        LKML <linux-kernel@vger.kernel.org>, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH 1/8] fs/9p: Deletion of unnecessary checks before the
 function call "p9_client_clunk"
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On Mon, 5 Jan 2015, SF Markus Elfring wrote:

> >> The p9_client_clunk() function tests whether its argument is NULL
> >> and then returns immediately. Thus the test around the call is not needed.
> >>
> > 
> > Not true.  You are not allowed to call p9_client_clunk(NULL).
> 
> I find that it will work in principle if we refer to the same
> function implementation.
> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/net/9p/client.c?id=d8282ea05ad119247122de23db7d48ad6098cfa2#n1448
> http://lxr.free-electrons.com/source/net/9p/client.c#L1448

What do you mean by "work in principle"?  One possible issue is the return 
value - I don't have the original patch so I don't know what is the call 
site, so I don't know if that is an issue.  But you don't want to do a 
dump_stack for no reason.  That would at best be very misleading, and I 
would imagine be quite expensive.

julia