From patchwork Fri Jun 1 16:07:26 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Salisbury X-Patchwork-Id: 924148 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=canonical.com Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 40y8P80gFZz9s2S; Sat, 2 Jun 2018 02:07:40 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1fOmaR-0002q0-AK; Fri, 01 Jun 2018 16:07:31 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.86_2) (envelope-from ) id 1fOmaQ-0002pK-3M for kernel-team@lists.ubuntu.com; Fri, 01 Jun 2018 16:07:30 +0000 Received: from 1.general.jsalisbury.us.vpn ([10.172.67.212] helo=salisbury) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1fOmaP-0005VX-Ll for kernel-team@lists.ubuntu.com; Fri, 01 Jun 2018 16:07:29 +0000 Received: by salisbury (Postfix, from userid 1000) id 8B3827E2674; Fri, 1 Jun 2018 12:07:28 -0400 (EDT) From: Joseph Salisbury To: kernel-team@lists.ubuntu.com Subject: [SRU][Bionic][PATCH 1/3] vmxnet3: avoid xmit reset due to a race in vmxnet3 Date: Fri, 1 Jun 2018 12:07:26 -0400 Message-Id: <9dfa9806f89752ea2f299c4bf6616a0a1d570998.1525385262.git.joseph.salisbury@canonical.com> X-Mailer: git-send-email 2.17.0 In-Reply-To: References: In-Reply-To: References: X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" From: Ronak Doshi BugLink: http://bugs.launchpad.net/bugs/1768143 The field txNumDeferred is used by the driver to keep track of the number of packets it has pushed to the emulation. The driver increments it on pushing the packet to the emulation and the emulation resets it to 0 at the end of the transmit. There is a possibility of a race either when (a) ESX is under heavy load or (b) workload inside VM is of low packet rate. This race results in xmit hangs when network coalescing is disabled. This change creates a local copy of txNumDeferred and uses it to perform ring arithmetic. Reported-by: Noriho Tanaka Signed-off-by: Ronak Doshi Acked-by: Shrikrishna Khare Signed-off-by: David S. Miller (back ported from commit 7a4c003d6921e2af215f4790aa43a292bdc78be0) Signed-off-by: Joseph Salisbury --- drivers/net/vmxnet3/vmxnet3_drv.c | 13 ++++++++----- drivers/net/vmxnet3/vmxnet3_int.h | 4 ++-- 2 files changed, 10 insertions(+), 7 deletions(-) diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c index cf95290..345e738 100644 --- a/drivers/net/vmxnet3/vmxnet3_drv.c +++ b/drivers/net/vmxnet3/vmxnet3_drv.c @@ -977,6 +977,8 @@ vmxnet3_tq_xmit(struct sk_buff *skb, struct vmxnet3_tx_queue *tq, { int ret; u32 count; + int num_pkts; + int tx_num_deferred; unsigned long flags; struct vmxnet3_tx_ctx ctx; union Vmxnet3_GenericDesc *gdesc; @@ -1075,12 +1077,12 @@ vmxnet3_tq_xmit(struct sk_buff *skb, struct vmxnet3_tx_queue *tq, #else gdesc = ctx.sop_txd; #endif + tx_num_deferred = le32_to_cpu(tq->shared->txNumDeferred); if (ctx.mss) { gdesc->txd.hlen = ctx.eth_ip_hdr_size + ctx.l4_hdr_size; gdesc->txd.om = VMXNET3_OM_TSO; gdesc->txd.msscof = ctx.mss; - le32_add_cpu(&tq->shared->txNumDeferred, (skb->len - - gdesc->txd.hlen + ctx.mss - 1) / ctx.mss); + num_pkts = (skb->len - gdesc->txd.hlen + ctx.mss - 1) / ctx.mss; } else { if (skb->ip_summed == CHECKSUM_PARTIAL) { gdesc->txd.hlen = ctx.eth_ip_hdr_size; @@ -1091,8 +1093,10 @@ vmxnet3_tq_xmit(struct sk_buff *skb, struct vmxnet3_tx_queue *tq, gdesc->txd.om = 0; gdesc->txd.msscof = 0; } - le32_add_cpu(&tq->shared->txNumDeferred, 1); + num_pkts = 1; } + le32_add_cpu(&tq->shared->txNumDeferred, num_pkts); + tx_num_deferred += num_pkts; if (skb_vlan_tag_present(skb)) { gdesc->txd.ti = 1; @@ -1118,8 +1122,7 @@ vmxnet3_tq_xmit(struct sk_buff *skb, struct vmxnet3_tx_queue *tq, spin_unlock_irqrestore(&tq->tx_lock, flags); - if (le32_to_cpu(tq->shared->txNumDeferred) >= - le32_to_cpu(tq->shared->txThreshold)) { + if (tx_num_deferred >= le32_to_cpu(tq->shared->txThreshold)) { tq->shared->txNumDeferred = 0; VMXNET3_WRITE_BAR0_REG(adapter, VMXNET3_REG_TXPROD + tq->qid * 8, diff --git a/drivers/net/vmxnet3/vmxnet3_int.h b/drivers/net/vmxnet3/vmxnet3_int.h index 9c51b8b..dc7e141 100644 --- a/drivers/net/vmxnet3/vmxnet3_int.h +++ b/drivers/net/vmxnet3/vmxnet3_int.h @@ -69,10 +69,10 @@ /* * Version numbers */ -#define VMXNET3_DRIVER_VERSION_STRING "1.4.a.0-k" +#define VMXNET3_DRIVER_VERSION_STRING "1.4.12.0-k" /* a 32-bit int, each byte encode a verion number in VMXNET3_DRIVER_VERSION */ -#define VMXNET3_DRIVER_VERSION_NUM 0x01040a00 +#define VMXNET3_DRIVER_VERSION_NUM 0x01040c00 #if defined(CONFIG_PCI_MSI) /* RSS only makes sense if MSI-X is supported. */