Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751056AbWIWFdz (ORCPT ); Sat, 23 Sep 2006 01:33:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751070AbWIWFdz (ORCPT ); Sat, 23 Sep 2006 01:33:55 -0400 Received: from smtp.osdl.org ([65.172.181.4]:51178 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1751056AbWIWFdx (ORCPT ); Sat, 23 Sep 2006 01:33:53 -0400 Date: Fri, 22 Sep 2006 22:33:48 -0700 From: Andrew Morton To: David Miller Cc: auke-jan.h.kok@intel.com, Holger.Kiehl@dwd.de, linux-kernel@vger.kernel.org, linux-net@vger.kernel.org, netdev@vger.kernel.org, john.ronciak@intel.com Subject: Re: 2.6.1[78] page allocation failure. order:3, mode:0x20 Message-Id: <20060922223348.1b24fda5.akpm@osdl.org> In-Reply-To: <20060922.222507.74751476.davem@davemloft.net> References: <20060922004253.2e2e2612.akpm@osdl.org> <4514190C.8010901@intel.com> <20060922215000.c1fde093.akpm@osdl.org> <20060922.222507.74751476.davem@davemloft.net> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3806 Lines: 94 On Fri, 22 Sep 2006 22:25:07 -0700 (PDT) David Miller wrote: > From: Andrew Morton > Date: Fri, 22 Sep 2006 21:50:00 -0700 > > > On Fri, 22 Sep 2006 10:10:36 -0700 > > Auke Kok wrote: > > > > > e1000: account for NET_IP_ALIGN when calculating bufsiz > > > > > > Account for NET_IP_ALIGN when requesting buffer sizes from netdev_alloc_skb to > > > reduce slab allocation by half. > > > > Could we please do whatever is needed to get this blessed and merged? This > > is such a common problem on such a common driver that I would suggest that > > we want this in 2.6.18.x as well. At least, I'd expect distributors to > > ship this fix (they're nuts if they don't) and so it makes sense to deliver > > it from kernel.org. > > The NET_IP_ALIGN existed not just for fun :) There are ramifications > for removing it. It's still there, isn't it? For the 9k MTU case, for example, we end up allocating 16384 byte skbs instead of 32786 kbytes ones. diff -puN drivers/net/e1000/e1000_main.c~e1000-account-for-net_ip_align-when-calculating-bufsiz drivers/net/e1000/e1000_main.c --- a/drivers/net/e1000/e1000_main.c~e1000-account-for-net_ip_align-when-calculating-bufsiz +++ a/drivers/net/e1000/e1000_main.c @@ -1101,7 +1101,7 @@ e1000_sw_init(struct e1000_adapter *adap pci_read_config_word(pdev, PCI_COMMAND, &hw->pci_cmd_word); - adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE; + adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE + NET_IP_ALIGN; adapter->rx_ps_bsize0 = E1000_RXBUFFER_128; hw->max_frame_size = netdev->mtu + ENET_HEADER_SIZE + ETHERNET_FCS_SIZE; @@ -3163,26 +3163,27 @@ e1000_change_mtu(struct net_device *netd * larger slab size * i.e. RXBUFFER_2048 --> size-4096 slab */ - if (max_frame <= E1000_RXBUFFER_256) + if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_256) adapter->rx_buffer_len = E1000_RXBUFFER_256; - else if (max_frame <= E1000_RXBUFFER_512) + else if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_512) adapter->rx_buffer_len = E1000_RXBUFFER_512; - else if (max_frame <= E1000_RXBUFFER_1024) + else if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_1024) adapter->rx_buffer_len = E1000_RXBUFFER_1024; - else if (max_frame <= E1000_RXBUFFER_2048) + else if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_2048) adapter->rx_buffer_len = E1000_RXBUFFER_2048; - else if (max_frame <= E1000_RXBUFFER_4096) + else if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_4096) adapter->rx_buffer_len = E1000_RXBUFFER_4096; - else if (max_frame <= E1000_RXBUFFER_8192) + else if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_8192) adapter->rx_buffer_len = E1000_RXBUFFER_8192; - else if (max_frame <= E1000_RXBUFFER_16384) + else adapter->rx_buffer_len = E1000_RXBUFFER_16384; /* adjust allocation if LPE protects us, and we aren't using SBP */ if (!adapter->hw.tbi_compatibility_on && ((max_frame == MAXIMUM_ETHERNET_FRAME_SIZE) || (max_frame == MAXIMUM_ETHERNET_VLAN_SIZE))) - adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE; + adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE + + NET_IP_ALIGN; netdev->mtu = new_mtu; @@ -4002,7 +4003,8 @@ e1000_alloc_rx_buffers(struct e1000_adap struct e1000_buffer *buffer_info; struct sk_buff *skb; unsigned int i; - unsigned int bufsz = adapter->rx_buffer_len + NET_IP_ALIGN; + /* we have already accounted for NET_IP_ALIGN */ + unsigned int bufsz = adapter->rx_buffer_len; i = rx_ring->next_to_use; buffer_info = &rx_ring->buffer_info[i]; _ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/