From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Borkmann <dborkman@redhat.com>
Subject: Re: Single socket with TX_RING and RX_RING
Date: Wed, 15 May 2013 15:20:45 +0200
Message-ID: <51938BAD.5050502@redhat.com>
References: <loom.20130515T144941-798@post.gmane.org>
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On 05/15/2013 02:53 PM, Ricardo Tub=EDo wrote:
> Once I tell kernel to export the TX_RING through setsockopt() (see co=
de
> below) I always get an error (EBUSY) if i try to tell kernel to expor=
t the
> RX_RING with the same socket descriptor. Therefore, I have to open an
> additional socket for the RX_RING and I require of two sockets when I=
 though
> that I would only require of one socket for both TX and RX using mmap=
()ed
> memory.
>
> Do I need both sockets or am I doing something wrong?

The second time you call init_ring() in your code e.g. with TX_RING, wh=
ere
you have previously set it up for the RX_RING. The kernel will give you
-EBUSY because the packet socket is already mmap(2)'ed.