From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: [PATCH net-next] be2net: allocate more headroom in incoming skbs Date: Wed, 25 Jan 2012 14:56:30 +0100 Message-ID: <1327499790.2425.45.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev , Ian Campbell , Vasundhara Volam , Sathya Perla , Ajit Khaparde To: David Miller Return-path: Received: from mail-bk0-f46.google.com ([209.85.214.46]:45560 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755065Ab2AYN4e (ORCPT ); Wed, 25 Jan 2012 08:56:34 -0500 Received: by bkas6 with SMTP id s6so4405246bka.19 for ; Wed, 25 Jan 2012 05:56:33 -0800 (PST) Sender: netdev-owner@vger.kernel.org List-ID: Allocation of 64 bytes in skb headroom is not enough if we have to pull ethernet + ipv6 + tcp headers, and/or extra tunneling header. Its currently not noticed because netdev_alloc_skb_ip_align(64) give us more room, thanks to power-of-two kmalloc() roundups. Make sure we ask for 128 bytes so that side effects of upcoming patches from Ian Campbell dont decrease benet rx performance, because of extra skb head reallocations. Signed-off-by: Eric Dumazet Cc: Ian Campbell Cc: Vasundhara Volam Cc: Sathya Perla Cc: Ajit Khaparde --- drivers/net/ethernet/emulex/benet/be.h | 3 +++ drivers/net/ethernet/emulex/benet/be_main.c | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/emulex/benet/be.h b/drivers/net/ethernet/emulex/benet/be.h index cbdec25..5ee7cc0 100644 --- a/drivers/net/ethernet/emulex/benet/be.h +++ b/drivers/net/ethernet/emulex/benet/be.h @@ -74,6 +74,9 @@ static inline char *nic_name(struct pci_dev *pdev) /* Number of bytes of an RX frame that are copied to skb->data */ #define BE_HDR_LEN ((u16) 64) +/* allocate extra space to allow tunneling decapsulation without head reallocation */ +#define BE_RX_SKB_ALLOC_SIZE (BE_HDR_LEN + 64) + #define BE_MAX_JUMBO_FRAME_SIZE 9018 #define BE_MIN_MTU 256 diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c index e703d64..0fbf365 100644 --- a/drivers/net/ethernet/emulex/benet/be_main.c +++ b/drivers/net/ethernet/emulex/benet/be_main.c @@ -1189,7 +1189,7 @@ static void be_rx_compl_process(struct be_adapter *adapter, struct net_device *netdev = adapter->netdev; struct sk_buff *skb; - skb = netdev_alloc_skb_ip_align(netdev, BE_HDR_LEN); + skb = netdev_alloc_skb_ip_align(netdev, BE_RX_SKB_ALLOC_SIZE); if (unlikely(!skb)) { rx_stats(rxo)->rx_drops_no_skbs++; be_rx_compl_discard(adapter, rxo, rxcp);