[dpdk-stable] patch 'net/virtio: fix queue setup consistency' has been queued to LTS release 16.11.4

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to LTS release 16.11.4

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 11/01/17. So please
shout if anyone has objections.

Thanks.

Kind regards,
Luca Boccassi

---
>From 29113fef0f37476ba992e00ad17cd23a7eb6ac89 Mon Sep 17 00:00:00 2001
From: Olivier Matz <olivier.matz at 6wind.com>
Date: Thu, 7 Sep 2017 14:13:43 +0200
Subject: [PATCH] net/virtio: fix queue setup consistency

[ upstream commit efc83a1e7fc319876835738871bf968e7ed5c935 ]

In rx/tx queue setup functions, some code is executed only if
use_simple_rxtx == 1. The value of this variable can change depending on
the offload flags or sse support. If Rx queue setup is called before Tx
queue setup, it can result in an invalid configuration:

- dev_configure is called: use_simple_rxtx is initialized to 0
- rx queue setup is called: queues are initialized without simple path
  support
- tx queue setup is called: use_simple_rxtx switch to 1, and simple
  Rx/Tx handlers are selected

Fix this by postponing a part of Rx/Tx queue initialization in
dev_start(), as it was the case in the initial implementation.

Fixes: 48cec290a3d2 ("net/virtio: move queue configure code to proper place")

Signed-off-by: Olivier Matz <olivier.matz at 6wind.com>
Acked-by: Yuanhan Liu <yliu at fridaylinux.org>
---
 drivers/net/virtio/virtio_ethdev.c | 13 +++++++++++++
 drivers/net/virtio/virtio_ethdev.h |  6 ++++++
 drivers/net/virtio/virtio_rxtx.c   | 40 ++++++++++++++++++++++++++++++--------
 3 files changed, 51 insertions(+), 8 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 67ebb1e5b..6903368db 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1523,6 +1523,19 @@ virtio_dev_start(struct rte_eth_dev *dev)
 	struct virtnet_rx *rxvq;
 	struct virtnet_tx *txvq __rte_unused;
 	struct virtio_hw *hw = dev->data->dev_private;
+	int ret;
+
+	/* Finish the initialization of the queues */
+	for (i = 0; i < dev->data->nb_rx_queues; i++) {
+		ret = virtio_dev_rx_queue_setup_finish(dev, i);
+		if (ret < 0)
+			return ret;
+	}
+	for (i = 0; i < dev->data->nb_tx_queues; i++) {
+		ret = virtio_dev_tx_queue_setup_finish(dev, i);
+		if (ret < 0)
+			return ret;
+	}
 
 	/* check if lsc interrupt feature is enabled */
 	if (dev->data->dev_conf.intr_conf.lsc) {
diff --git a/drivers/net/virtio/virtio_ethdev.h b/drivers/net/virtio/virtio_ethdev.h
index 4feccf939..c491ec1b0 100644
--- a/drivers/net/virtio/virtio_ethdev.h
+++ b/drivers/net/virtio/virtio_ethdev.h
@@ -88,10 +88,16 @@ int  virtio_dev_rx_queue_setup(struct rte_eth_dev *dev, uint16_t rx_queue_id,
 		const struct rte_eth_rxconf *rx_conf,
 		struct rte_mempool *mb_pool);
 
+int virtio_dev_rx_queue_setup_finish(struct rte_eth_dev *dev,
+				uint16_t rx_queue_id);
+
 int  virtio_dev_tx_queue_setup(struct rte_eth_dev *dev, uint16_t tx_queue_id,
 		uint16_t nb_tx_desc, unsigned int socket_id,
 		const struct rte_eth_txconf *tx_conf);
 
+int virtio_dev_tx_queue_setup_finish(struct rte_eth_dev *dev,
+				uint16_t tx_queue_id);
+
 uint16_t virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
 		uint16_t nb_pkts);
 
diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index a33ef1a88..ad582f3e5 100644
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -412,9 +412,6 @@ virtio_dev_rx_queue_setup(struct rte_eth_dev *dev,
 	struct virtio_hw *hw = dev->data->dev_private;
 	struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 	struct virtnet_rx *rxvq;
-	int error, nbufs;
-	struct rte_mbuf *m;
-	uint16_t desc_idx;
 
 	PMD_INIT_FUNC_TRACE();
 
@@ -431,10 +428,24 @@ virtio_dev_rx_queue_setup(struct rte_eth_dev *dev,
 	}
 	dev->data->rx_queues[queue_idx] = rxvq;
 
+	return 0;
+}
+
+int
+virtio_dev_rx_queue_setup_finish(struct rte_eth_dev *dev, uint16_t queue_idx)
+{
+	uint16_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_RQ_QUEUE_IDX;
+	struct virtio_hw *hw = dev->data->dev_private;
+	struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
+	struct virtnet_rx *rxvq = &vq->rxq;
+	struct rte_mbuf *m;
+	uint16_t desc_idx;
+	int error, nbufs;
+
+	PMD_INIT_FUNC_TRACE();
 
 	/* Allocate blank mbufs for the each rx descriptor */
 	nbufs = 0;
-	error = ENOSPC;
 
 	if (hw->use_simple_rxtx) {
 		for (desc_idx = 0; desc_idx < vq->vq_nentries;
@@ -525,7 +536,6 @@ virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
 	struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 	struct virtnet_tx *txvq;
 	uint16_t tx_free_thresh;
-	uint16_t desc_idx;
 
 	PMD_INIT_FUNC_TRACE();
 
@@ -554,9 +564,24 @@ virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
 
 	vq->vq_free_thresh = tx_free_thresh;
 
+	dev->data->tx_queues[queue_idx] = txvq;
+	return 0;
+}
+
+int
+virtio_dev_tx_queue_setup_finish(struct rte_eth_dev *dev,
+				uint16_t queue_idx)
+{
+	uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
+	struct virtio_hw *hw = dev->data->dev_private;
+	struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
+	uint16_t mid_idx = vq->vq_nentries >> 1;
+	struct virtnet_tx *txvq = &vq->txq;
+	uint16_t desc_idx;
+
+	PMD_INIT_FUNC_TRACE();
+
 	if (hw->use_simple_rxtx) {
-		uint16_t mid_idx  = vq->vq_nentries >> 1;
-
 		for (desc_idx = 0; desc_idx < mid_idx; desc_idx++) {
 			vq->vq_ring.avail->ring[desc_idx] =
 				desc_idx + mid_idx;
@@ -578,7 +603,6 @@ virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
 
 	VIRTQUEUE_DUMP(vq);
 
-	dev->data->tx_queues[queue_idx] = txvq;
 	return 0;
 }
 
-- 
2.11.0