From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F364EC5ACAE for ; Wed, 11 Sep 2019 16:50:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D521720838 for ; Wed, 11 Sep 2019 16:50:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729256AbfIKQt6 (ORCPT ); Wed, 11 Sep 2019 12:49:58 -0400 Received: from mga14.intel.com ([192.55.52.115]:31944 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728825AbfIKQt6 (ORCPT ); Wed, 11 Sep 2019 12:49:58 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Sep 2019 09:49:57 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,492,1559545200"; d="scan'208";a="179078817" Received: from jtkirshe-desk1.jf.intel.com ([134.134.177.96]) by orsmga008.jf.intel.com with ESMTP; 11 Sep 2019 09:49:57 -0700 From: Jeff Kirsher To: davem@davemloft.net Cc: Ilya Maximets , netdev@vger.kernel.org, nhorman@redhat.com, sassmann@redhat.com, stable@vger.kernel.org, William Tu , Eelco Chaudron , Jeff Kirsher Subject: [net 2/2] ixgbe: fix double clean of Tx descriptors with xdp Date: Wed, 11 Sep 2019 09:49:55 -0700 Message-Id: <20190911164955.10644-3-jeffrey.t.kirsher@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190911164955.10644-1-jeffrey.t.kirsher@intel.com> References: <20190911164955.10644-1-jeffrey.t.kirsher@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Ilya Maximets Tx code doesn't clear the descriptors' status after cleaning. So, if the budget is larger than number of used elems in a ring, some descriptors will be accounted twice and xsk_umem_complete_tx will move prod_tail far beyond the prod_head breaking the completion queue ring. Fix that by limiting the number of descriptors to clean by the number of used descriptors in the Tx ring. 'ixgbe_clean_xdp_tx_irq()' function refactored to look more like 'ixgbe_xsk_clean_tx_ring()' since we're allowed to directly use 'next_to_clean' and 'next_to_use' indexes. CC: stable@vger.kernel.org Fixes: 8221c5eba8c1 ("ixgbe: add AF_XDP zero-copy Tx support") Signed-off-by: Ilya Maximets Tested-by: William Tu Tested-by: Eelco Chaudron Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c | 29 ++++++++------------ 1 file changed, 11 insertions(+), 18 deletions(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c index 6b609553329f..a3b6d8c89127 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c @@ -633,19 +633,17 @@ static void ixgbe_clean_xdp_tx_buffer(struct ixgbe_ring *tx_ring, bool ixgbe_clean_xdp_tx_irq(struct ixgbe_q_vector *q_vector, struct ixgbe_ring *tx_ring, int napi_budget) { + u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use; unsigned int total_packets = 0, total_bytes = 0; - u32 i = tx_ring->next_to_clean, xsk_frames = 0; - unsigned int budget = q_vector->tx.work_limit; struct xdp_umem *umem = tx_ring->xsk_umem; union ixgbe_adv_tx_desc *tx_desc; struct ixgbe_tx_buffer *tx_bi; - bool xmit_done; + u32 xsk_frames = 0; - tx_bi = &tx_ring->tx_buffer_info[i]; - tx_desc = IXGBE_TX_DESC(tx_ring, i); - i -= tx_ring->count; + tx_bi = &tx_ring->tx_buffer_info[ntc]; + tx_desc = IXGBE_TX_DESC(tx_ring, ntc); - do { + while (ntc != ntu) { if (!(tx_desc->wb.status & cpu_to_le32(IXGBE_TXD_STAT_DD))) break; @@ -661,22 +659,18 @@ bool ixgbe_clean_xdp_tx_irq(struct ixgbe_q_vector *q_vector, tx_bi++; tx_desc++; - i++; - if (unlikely(!i)) { - i -= tx_ring->count; + ntc++; + if (unlikely(ntc == tx_ring->count)) { + ntc = 0; tx_bi = tx_ring->tx_buffer_info; tx_desc = IXGBE_TX_DESC(tx_ring, 0); } /* issue prefetch for next Tx descriptor */ prefetch(tx_desc); + } - /* update budget accounting */ - budget--; - } while (likely(budget)); - - i += tx_ring->count; - tx_ring->next_to_clean = i; + tx_ring->next_to_clean = ntc; u64_stats_update_begin(&tx_ring->syncp); tx_ring->stats.bytes += total_bytes; @@ -688,8 +682,7 @@ bool ixgbe_clean_xdp_tx_irq(struct ixgbe_q_vector *q_vector, if (xsk_frames) xsk_umem_complete_tx(umem, xsk_frames); - xmit_done = ixgbe_xmit_zc(tx_ring, q_vector->tx.work_limit); - return budget > 0 && xmit_done; + return ixgbe_xmit_zc(tx_ring, q_vector->tx.work_limit); } int ixgbe_xsk_async_xmit(struct net_device *dev, u32 qid) -- 2.21.0