From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next-2.6] ip_gre: lockless xmit
Date: Wed, 29 Sep 2010 10:18:08 +0200
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Cc: David Miller <davem@davemloft.net>, netdev <netdev@vger.kernel.org>
To: nicolas.dichtel@6wind.com
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Le mercredi 29 septembre 2010 =C3=A0 10:10 +0200, Nicolas Dichtel a =C3=
=A9crit :
> NETIF_F_LLTX is marked as deprecated:
>=20
> include/linux/netdevice.h:
> #define NETIF_F_LLTX            4096    /* LockLess TX - deprecated.=20
> Please */
>                                          /* do not use LLTX in new=20
> drivers */
>=20
> Is it right to use it?
>=20

In this particular case (and drivers/net/loopback.c), yes.

This is the only way to avoid the locking in core network
(net/core/dev.c)

What is deprecated is to assert NETIF_F_LLTX and yet, use a lock in the
ndo_xmit() driver method.