From patchwork Fri Apr 17 00:06:09 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Catherine Sullivan X-Patchwork-Id: 461894 X-Patchwork-Delegate: jeffrey.t.kirsher@intel.com Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from fraxinus.osuosl.org (fraxinus.osuosl.org [140.211.166.137]) by ozlabs.org (Postfix) with ESMTP id C544F1402A6 for ; Fri, 17 Apr 2015 10:03:31 +1000 (AEST) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 24F9D89E86; Fri, 17 Apr 2015 00:03:31 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id AzyrKQuhK0Uo; Fri, 17 Apr 2015 00:03:29 +0000 (UTC) Received: from ash.osuosl.org (ash.osuosl.org [140.211.166.34]) by fraxinus.osuosl.org (Postfix) with ESMTP id 8C2C289E85; Fri, 17 Apr 2015 00:03:29 +0000 (UTC) X-Original-To: intel-wired-lan@lists.osuosl.org Delivered-To: intel-wired-lan@lists.osuosl.org Received: from fraxinus.osuosl.org (fraxinus.osuosl.org [140.211.166.137]) by ash.osuosl.org (Postfix) with ESMTP id 302031C223A for ; Fri, 17 Apr 2015 00:03:28 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 2C24089E88 for ; Fri, 17 Apr 2015 00:03:28 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id jWbsSD_S6LIL for ; Fri, 17 Apr 2015 00:03:27 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by fraxinus.osuosl.org (Postfix) with ESMTP id B0EA789E86 for ; Fri, 17 Apr 2015 00:03:27 +0000 (UTC) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga102.jf.intel.com with ESMTP; 16 Apr 2015 17:03:27 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,591,1422950400"; d="scan'208";a="481989715" Received: from catheri1-tigger.jf.intel.com ([134.134.176.92]) by FMSMGA003.fm.intel.com with ESMTP; 16 Apr 2015 17:03:27 -0700 From: Catherine Sullivan To: intel-wired-lan@lists.osuosl.org Date: Thu, 16 Apr 2015 20:06:09 -0400 Message-Id: <1429229172-143692-13-git-send-email-catherine.sullivan@intel.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1429229172-143692-1-git-send-email-catherine.sullivan@intel.com> References: <1429229172-143692-1-git-send-email-catherine.sullivan@intel.com> Cc: Daniel Borkmann , Eric Dumazet Subject: [Intel-wired-lan] [net-next S4 12/15] i40evf: skb->xmit_more support X-BeenThere: intel-wired-lan@lists.osuosl.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Intel Wired Ethernet Linux Kernel Driver Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-wired-lan-bounces@lists.osuosl.org Sender: "Intel-wired-lan" From: Jesse Brandeburg Eric added support for skb->xmit_more in i40e, this ports that into i40evf as well. Support skb->xmit_more in i40evf is straightforward; we need to move around i40e_maybe_stop_tx() call to correctly test netif_xmit_stopped() before taking the decision to not kick the NIC. Signed-off-by: Eric Dumazet Signed-off-by: Daniel Borkmann Signed-off-by: Jesse Brandeburg Change-ID: Idddda6a2e4a7ab335631c91ced51f55b25eb8468 Tested-by: Jim Young --- drivers/net/ethernet/intel/i40evf/i40e_txrx.c | 88 ++++++++++++++------------- 1 file changed, 47 insertions(+), 41 deletions(-) diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c index e1a44dd..4f77d38 100644 --- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c @@ -1672,6 +1672,47 @@ linearize_chk_done: } /** + * __i40evf_maybe_stop_tx - 2nd level check for tx stop conditions + * @tx_ring: the ring to be checked + * @size: the size buffer we want to assure is available + * + * Returns -EBUSY if a stop is needed, else 0 + **/ +static inline int __i40evf_maybe_stop_tx(struct i40e_ring *tx_ring, int size) +{ + netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index); + /* Memory barrier before checking head and tail */ + smp_mb(); + + /* Check again in a case another CPU has just made room available. */ + if (likely(I40E_DESC_UNUSED(tx_ring) < size)) + return -EBUSY; + + /* A reprieve! - use start_queue because it doesn't call schedule */ + netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index); + ++tx_ring->tx_stats.restart_queue; + return 0; +} + +/** + * i40evf_maybe_stop_tx - 1st level check for tx stop conditions + * @tx_ring: the ring to be checked + * @size: the size buffer we want to assure is available + * + * Returns 0 if stop is not needed + **/ +#ifdef I40E_FCOE +int i40evf_maybe_stop_tx(struct i40e_ring *tx_ring, int size) +#else +static int i40evf_maybe_stop_tx(struct i40e_ring *tx_ring, int size) +#endif +{ + if (likely(I40E_DESC_UNUSED(tx_ring) >= size)) + return 0; + return __i40evf_maybe_stop_tx(tx_ring, size); +} + +/** * i40e_tx_map - Build the Tx descriptor * @tx_ring: ring to send buffer on * @skb: send buffer @@ -1808,8 +1849,12 @@ static void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb, tx_ring->next_to_use = i; + i40evf_maybe_stop_tx(tx_ring, DESC_NEEDED); /* notify HW of packet */ - writel(i, tx_ring->tail); + if (!skb->xmit_more || + netif_xmit_stopped(netdev_get_tx_queue(tx_ring->netdev, + tx_ring->queue_index))) + writel(i, tx_ring->tail); return; @@ -1831,43 +1876,6 @@ dma_error: } /** - * __i40e_maybe_stop_tx - 2nd level check for tx stop conditions - * @tx_ring: the ring to be checked - * @size: the size buffer we want to assure is available - * - * Returns -EBUSY if a stop is needed, else 0 - **/ -static inline int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size) -{ - netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index); - /* Memory barrier before checking head and tail */ - smp_mb(); - - /* Check again in a case another CPU has just made room available. */ - if (likely(I40E_DESC_UNUSED(tx_ring) < size)) - return -EBUSY; - - /* A reprieve! - use start_queue because it doesn't call schedule */ - netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index); - ++tx_ring->tx_stats.restart_queue; - return 0; -} - -/** - * i40e_maybe_stop_tx - 1st level check for tx stop conditions - * @tx_ring: the ring to be checked - * @size: the size buffer we want to assure is available - * - * Returns 0 if stop is not needed - **/ -static int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size) -{ - if (likely(I40E_DESC_UNUSED(tx_ring) >= size)) - return 0; - return __i40e_maybe_stop_tx(tx_ring, size); -} - -/** * i40e_xmit_descriptor_count - calculate number of tx descriptors needed * @skb: send buffer * @tx_ring: ring to send buffer on @@ -1892,7 +1900,7 @@ static int i40e_xmit_descriptor_count(struct sk_buff *skb, count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size); count += TXD_USE_COUNT(skb_headlen(skb)); - if (i40e_maybe_stop_tx(tx_ring, count + 4 + 1)) { + if (i40evf_maybe_stop_tx(tx_ring, count + 4 + 1)) { tx_ring->tx_stats.tx_busy++; return 0; } @@ -1968,8 +1976,6 @@ static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb, i40e_tx_map(tx_ring, skb, first, tx_flags, hdr_len, td_cmd, td_offset); - i40e_maybe_stop_tx(tx_ring, DESC_NEEDED); - return NETDEV_TX_OK; out_drop: