From patchwork Wed Aug 19 01:17:09 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: stephen hemminger X-Patchwork-Id: 31612 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@bilbo.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from ozlabs.org (ozlabs.org [203.10.76.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.ozlabs.org", Issuer "CA Cert Signing Authority" (verified OK)) by bilbo.ozlabs.org (Postfix) with ESMTPS id 81C34B7079 for ; Wed, 19 Aug 2009 11:23:01 +1000 (EST) Received: by ozlabs.org (Postfix) id 756FEDDD0B; Wed, 19 Aug 2009 11:23:01 +1000 (EST) Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by ozlabs.org (Postfix) with ESMTP id F0A49DDD01 for ; Wed, 19 Aug 2009 11:23:00 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751303AbZHSBWq (ORCPT ); Tue, 18 Aug 2009 21:22:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751263AbZHSBWq (ORCPT ); Tue, 18 Aug 2009 21:22:46 -0400 Received: from suva.vyatta.com ([76.74.103.44]:50671 "EHLO suva.vyatta.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750888AbZHSBWp (ORCPT ); Tue, 18 Aug 2009 21:22:45 -0400 Received: from suva.vyatta.com (suva [127.0.0.1]) by suva.vyatta.com (8.13.7/8.13.7) with ESMTP id n7J1MkMg026277; Tue, 18 Aug 2009 18:22:46 -0700 Received: (from shemminger@localhost) by suva.vyatta.com (8.13.7/8.13.7/Submit) id n7J1Mk8m026276; Tue, 18 Aug 2009 18:22:46 -0700 Message-Id: <20090819011738.913627761@vyatta.com> References: <20090819011704.685802801@vyatta.com> User-Agent: quilt/0.46-1 Date: Tue, 18 Aug 2009 18:17:09 -0700 From: Stephen Hemminger To: David Miller Cc: netdev@vger.kernel.org Subject: [PATCH 5/7] sky2: optimize transmit completion Content-Disposition: inline; filename=sky2-tx-re.patch Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Don't reference the list element in hardware transmit ring on transmit completion. The list element is updated by hardware, therefore it causes a cache miss. Do book keeping in software structure. Signed-off-by: Stephen Hemminger --- a/drivers/net/sky2.c 2009-08-18 10:50:35.096988776 -0700 +++ b/drivers/net/sky2.c 2009-08-18 11:27:05.272209365 -0700 @@ -1001,8 +1001,11 @@ static void sky2_prefetch_init(struct sk static inline struct sky2_tx_le *get_tx_le(struct sky2_port *sky2, u16 *slot) { struct sky2_tx_le *le = sky2->tx_le + *slot; + struct tx_ring_info *re = sky2->tx_ring + *slot; *slot = RING_NEXT(*slot, sky2->tx_ring_size); + re->flags = 0; + re->skb = NULL; le->ctrl = 0; return le; } @@ -1021,12 +1024,6 @@ static void tx_init(struct sky2_port *sk sky2->tx_last_upper = 0; } -static inline struct tx_ring_info *tx_le_re(struct sky2_port *sky2, - struct sky2_tx_le *le) -{ - return sky2->tx_ring + (le - sky2->tx_le); -} - /* Update chip's next pointer */ static inline void sky2_put_idx(struct sky2_hw *hw, unsigned q, u16 idx) { @@ -1563,6 +1560,19 @@ static unsigned tx_le_req(const struct s return count; } +static void sky2_tx_unmap(struct pci_dev *pdev, + const struct tx_ring_info *re) +{ + if (re->flags & TX_MAP_SINGLE) + pci_unmap_single(pdev, pci_unmap_addr(re, mapaddr), + pci_unmap_len(re, maplen), + PCI_DMA_TODEVICE); + else if (re->flags & TX_MAP_PAGE) + pci_unmap_page(pdev, pci_unmap_addr(re, mapaddr), + pci_unmap_len(re, maplen), + PCI_DMA_TODEVICE); +} + /* * Put one packet in ring for transmit. * A single packet can generate multiple list elements, and @@ -1667,16 +1677,17 @@ static int sky2_xmit_frame(struct sk_buf } } + re = sky2->tx_ring + slot; + re->flags = TX_MAP_SINGLE; + pci_unmap_addr_set(re, mapaddr, mapping); + pci_unmap_len_set(re, maplen, len); + le = get_tx_le(sky2, &slot); le->addr = cpu_to_le32(lower_32_bits(mapping)); le->length = cpu_to_le16(len); le->ctrl = ctrl; le->opcode = mss ? (OP_LARGESEND | HW_OWNER) : (OP_PACKET | HW_OWNER); - re = tx_le_re(sky2, le); - re->skb = skb; - pci_unmap_addr_set(re, mapaddr, mapping); - pci_unmap_len_set(re, maplen, len); for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { const skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; @@ -1695,18 +1706,19 @@ static int sky2_xmit_frame(struct sk_buf le->opcode = OP_ADDR64 | HW_OWNER; } + re = sky2->tx_ring + slot; + re->flags = TX_MAP_PAGE; + pci_unmap_addr_set(re, mapaddr, mapping); + pci_unmap_len_set(re, maplen, frag->size); + le = get_tx_le(sky2, &slot); le->addr = cpu_to_le32(lower_32_bits(mapping)); le->length = cpu_to_le16(frag->size); le->ctrl = ctrl; le->opcode = OP_BUFFER | HW_OWNER; - - re = tx_le_re(sky2, le); - re->skb = skb; - pci_unmap_addr_set(re, mapaddr, mapping); - pci_unmap_len_set(re, maplen, frag->size); } + re->skb = skb; le->ctrl |= EOP; sky2->tx_prod = slot; @@ -1720,23 +1732,9 @@ static int sky2_xmit_frame(struct sk_buf mapping_unwind: for (i = sky2->tx_prod; i != slot; i = RING_NEXT(i, sky2->tx_ring_size)) { - le = sky2->tx_le + i; re = sky2->tx_ring + i; - switch(le->opcode & ~HW_OWNER) { - case OP_LARGESEND: - case OP_PACKET: - pci_unmap_single(hw->pdev, - pci_unmap_addr(re, mapaddr), - pci_unmap_len(re, maplen), - PCI_DMA_TODEVICE); - break; - case OP_BUFFER: - pci_unmap_page(hw->pdev, pci_unmap_addr(re, mapaddr), - pci_unmap_len(re, maplen), - PCI_DMA_TODEVICE); - break; - } + sky2_tx_unmap(hw->pdev, re); } mapping_error: @@ -1759,34 +1757,18 @@ mapping_error: static void sky2_tx_complete(struct sky2_port *sky2, u16 done) { struct net_device *dev = sky2->netdev; - struct pci_dev *pdev = sky2->hw->pdev; unsigned idx; BUG_ON(done >= sky2->tx_ring_size); for (idx = sky2->tx_cons; idx != done; idx = RING_NEXT(idx, sky2->tx_ring_size)) { - struct sky2_tx_le *le = sky2->tx_le + idx; struct tx_ring_info *re = sky2->tx_ring + idx; + struct sk_buff *skb = re->skb; - switch(le->opcode & ~HW_OWNER) { - case OP_LARGESEND: - case OP_PACKET: - pci_unmap_single(pdev, - pci_unmap_addr(re, mapaddr), - pci_unmap_len(re, maplen), - PCI_DMA_TODEVICE); - break; - case OP_BUFFER: - pci_unmap_page(pdev, pci_unmap_addr(re, mapaddr), - pci_unmap_len(re, maplen), - PCI_DMA_TODEVICE); - break; - } - - if (le->ctrl & EOP) { - struct sk_buff *skb = re->skb; + sky2_tx_unmap(sky2->hw->pdev, re); + if (skb) { if (unlikely(netif_msg_tx_done(sky2))) printk(KERN_DEBUG "%s: tx done %u\n", dev->name, idx); --- a/drivers/net/sky2.h 2009-08-18 10:50:35.110991954 -0700 +++ b/drivers/net/sky2.h 2009-08-18 11:09:06.181966221 -0700 @@ -1984,6 +1984,9 @@ struct sky2_status_le { struct tx_ring_info { struct sk_buff *skb; + unsigned long flags; +#define TX_MAP_SINGLE 0x0001 +#define TX_MAP_PAGE 000002 DECLARE_PCI_UNMAP_ADDR(mapaddr); DECLARE_PCI_UNMAP_LEN(maplen); };