From patchwork Mon Jul 27 08:42:30 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiao Wang X-Patchwork-Id: 6609 Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [IPv6:::1]) by dpdk.org (Postfix) with ESMTP id CA4DEC530; Mon, 27 Jul 2015 10:43:08 +0200 (CEST) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by dpdk.org (Postfix) with ESMTP id 81CDEC44C for ; Mon, 27 Jul 2015 10:43:05 +0200 (CEST) Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga102.jf.intel.com with ESMTP; 27 Jul 2015 01:43:04 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.15,552,1432623600"; d="scan'208";a="755437802" Received: from shvmail01.sh.intel.com ([10.239.29.42]) by fmsmga001.fm.intel.com with ESMTP; 27 Jul 2015 01:43:03 -0700 Received: from shecgisg004.sh.intel.com (shecgisg004.sh.intel.com [10.239.29.89]) by shvmail01.sh.intel.com with ESMTP id t6R8h0nr023326; Mon, 27 Jul 2015 16:43:00 +0800 Received: from shecgisg004.sh.intel.com (localhost [127.0.0.1]) by shecgisg004.sh.intel.com (8.13.6/8.13.6/SuSE Linux 0.8) with ESMTP id t6R8gupD031094; Mon, 27 Jul 2015 16:42:58 +0800 Received: (from xiaowan1@localhost) by shecgisg004.sh.intel.com (8.13.6/8.13.6/Submit) id t6R8guHv031090; Mon, 27 Jul 2015 16:42:56 +0800 From: Wang Xiao W To: dev@dpdk.org Date: Mon, 27 Jul 2015 16:42:30 +0800 Message-Id: <1437986559-31016-7-git-send-email-xiao.w.wang@intel.com> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1437986559-31016-1-git-send-email-xiao.w.wang@intel.com> References: <1437986559-31016-1-git-send-email-xiao.w.wang@intel.com> Cc: Wang Xiao W Subject: [dpdk-dev] [PATCH 07/16] fm10k: mbx_update_max_size does not drop all X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" When we call update_max_size, it does not drop all oversized messages. This is due to the difficulty in performing this operation, since it is a FIFO which makes updating anything other than head or tail very difficult. To fix this, modify validate_msg_size to ensure that we error out later when trying to transmit the message that could be oversized. This will generally be a rare condition, as it requires the FIFO to include a message larger than the max_size negotiated during mailbox connect. Note that max_size is always smaller than rx.size, so it should be safe to use here. Also, update the update_max_size function header comment to clearly indicate that it does not drop all oversized messages, but only those at the head of the FIFO. Signed-off-by: Wang Xiao W --- drivers/net/fm10k/base/fm10k_mbx.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/net/fm10k/base/fm10k_mbx.c b/drivers/net/fm10k/base/fm10k_mbx.c index 12f10f8..0cdd24d 100644 --- a/drivers/net/fm10k/base/fm10k_mbx.c +++ b/drivers/net/fm10k/base/fm10k_mbx.c @@ -344,7 +344,7 @@ STATIC u16 fm10k_mbx_validate_msg_size(struct fm10k_mbx_info *mbx, u16 len) } while (total_len < len); /* message extends out of pushed section, but fits in FIFO */ - if ((len < total_len) && (msg_len <= mbx->rx.size)) + if ((len < total_len) && (msg_len <= mbx->max_size)) return 0; /* return length of invalid section */ @@ -1088,12 +1088,15 @@ STATIC void fm10k_mbx_reset_work(struct fm10k_mbx_info *mbx) } /** - * fm10k_mbx_update_max_size - Update the max_size and drop any large messages + * fm10k_mbx_update_max_size - Update the max_size and drop large messages * @mbx: pointer to mailbox * @size: new value for max_size * - * This function will update the max_size value and drop any outgoing messages - * from the head of the Tx FIFO that are larger than max_size. + * This function updates the max_size value and drops any outgoing messages + * at the head of the Tx FIFO if they are larger than max_size. It does not + * drop all messages, as this is too difficult to parse and remove them from + * the FIFO. Instead, rely on the checking to ensure that messages larger + * than max_size aren't pushed into the memory buffer. **/ STATIC void fm10k_mbx_update_max_size(struct fm10k_mbx_info *mbx, u16 size) {