From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Subject: Re: [PATCH net-next] igb: use build_skb()
Date: Thu, 02 Aug 2012 13:29:48 -0700
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Cc: Alexander Duyck <alexander.h.duyck@intel.com>,
	netdev <netdev@vger.kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Thu, 2012-08-02 at 17:51 +0200, Eric Dumazet wrote:
> From: Eric Dumazet <edumazet@google.com>
>=20
> By using netdev_alloc_frag() & build_skb() instead of legacy
> netdev_alloc_skb_ip_align() calls, we reduce number of cache misses in
> RX path and size of working set.
>=20
> For a given rx workload, number of 'inuse' sk_buff can be reduced to a
> very minimum, especially when packets are dropped by our stack.
>=20
> (Before this patch, default sk_buff allocation was 2048 sk_buffs in rx
> ring buffer)
>=20
> They are initialized right before being delivered to stack, so can
> stay
> hot in cpu caches.
>=20
> Ethernet header prefetching is more effective (old prefetch of
> skb->data
> paid a stall to access skb->data pointer)
>=20
> I have 15% performance increase in a RX stress test, removing SLUB
> slow
> path in the profiles.
>=20
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Cc: Alexander Duyck <alexander.h.duyck@intel.com>
> ---
>  drivers/net/ethernet/intel/igb/igb.h         |    8 ++
>  drivers/net/ethernet/intel/igb/igb_ethtool.c |   14 ++--
>  drivers/net/ethernet/intel/igb/igb_main.c    |   56 ++++++++++-------
>  3 files changed, 49 insertions(+), 29 deletions(-)=20

Thanks Eric, I have added this as well to my queue.

NOTE- you had some trailing whitespace errors in igb.h which I cleaned
up before adding to my queue.

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