Julio Faracco
2019-Nov-22 01:34 UTC
[PATCH] drivers: net: virtio_net: Implement a dev_watchdog handler
Driver virtio_net is not handling error events for TX provided by
dev_watchdog. This event is reached when transmission queue is having
problems to transmit packets. This could happen for any reason. To
enable it, driver should have .ndo_tx_timeout implemented.
This commit brings back virtnet_reset method to recover TX queues from a
error state. That function is called by schedule_work method and it puts
the reset function into work queue.
As the error cause is unknown at this moment, it would be better to
reset all queues.
Signed-off-by: Julio Faracco <jcfaracco at gmail.com>
Signed-off-by: Daiane Mendes <dnmendes76 at gmail.com>
Cc: Jason Wang <jasowang at redhat.com>
---
drivers/net/virtio_net.c | 95 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 94 insertions(+), 1 deletion(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 4d7d5434cc5d..31890d77eaf2 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -75,6 +75,7 @@ struct virtnet_sq_stats {
u64 xdp_tx;
u64 xdp_tx_drops;
u64 kicks;
+ u64 tx_timeouts;
};
struct virtnet_rq_stats {
@@ -98,6 +99,7 @@ static const struct virtnet_stat_desc virtnet_sq_stats_desc[]
= {
{ "xdp_tx", VIRTNET_SQ_STAT(xdp_tx) },
{ "xdp_tx_drops", VIRTNET_SQ_STAT(xdp_tx_drops) },
{ "kicks", VIRTNET_SQ_STAT(kicks) },
+ { "tx_timeouts", VIRTNET_SQ_STAT(tx_timeouts) },
};
static const struct virtnet_stat_desc virtnet_rq_stats_desc[] = {
@@ -211,6 +213,9 @@ struct virtnet_info {
/* Work struct for config space updates */
struct work_struct config_work;
+ /* Work struct for resetting the virtio-net driver. */
+ struct work_struct reset_work;
+
/* Does the affinity hint is set for virtqueues? */
bool affinity_hint_set;
@@ -1721,7 +1726,7 @@ static void virtnet_stats(struct net_device *dev,
int i;
for (i = 0; i < vi->max_queue_pairs; i++) {
- u64 tpackets, tbytes, rpackets, rbytes, rdrops;
+ u64 tpackets, tbytes, terrors, rpackets, rbytes, rdrops;
struct receive_queue *rq = &vi->rq[i];
struct send_queue *sq = &vi->sq[i];
@@ -1729,6 +1734,7 @@ static void virtnet_stats(struct net_device *dev,
start = u64_stats_fetch_begin_irq(&sq->stats.syncp);
tpackets = sq->stats.packets;
tbytes = sq->stats.bytes;
+ terrors = sq->stats.tx_timeouts;
} while (u64_stats_fetch_retry_irq(&sq->stats.syncp, start));
do {
@@ -1743,6 +1749,7 @@ static void virtnet_stats(struct net_device *dev,
tot->rx_bytes += rbytes;
tot->tx_bytes += tbytes;
tot->rx_dropped += rdrops;
+ tot->tx_errors += terrors;
}
tot->tx_dropped = dev->stats.tx_dropped;
@@ -2578,6 +2585,33 @@ static int virtnet_set_features(struct net_device *dev,
return 0;
}
+static void virtnet_tx_timeout(struct net_device *dev)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ u32 i;
+
+ netdev_warn(dev, "TX timeout stats:\n");
+ /* find the stopped queue the same way dev_watchdog() does */
+ for (i = 0; i < vi->curr_queue_pairs; i++) {
+ struct send_queue *sq = &vi->sq[i];
+
+ if (!netif_xmit_stopped(netdev_get_tx_queue(dev, i))) {
+ netdev_warn(dev, " Available send queue: %d, sq: %s, vq: %d, name:
%s\n",
+ i, sq->name, sq->vq->index, sq->vq->name);
+ continue;
+ }
+
+ u64_stats_update_begin(&sq->stats.syncp);
+ sq->stats.tx_timeouts++;
+ u64_stats_update_end(&sq->stats.syncp);
+
+ netdev_warn(dev, " Unavailable send queue: %d, sq: %s, vq: %d, name:
%s\n",
+ i, sq->name, sq->vq->index, sq->vq->name);
+ }
+
+ schedule_work(&vi->reset_work);
+}
+
static const struct net_device_ops virtnet_netdev = {
.ndo_open = virtnet_open,
.ndo_stop = virtnet_close,
@@ -2593,6 +2627,7 @@ static const struct net_device_ops virtnet_netdev = {
.ndo_features_check = passthru_features_check,
.ndo_get_phys_port_name = virtnet_get_phys_port_name,
.ndo_set_features = virtnet_set_features,
+ .ndo_tx_timeout = virtnet_tx_timeout,
};
static void virtnet_config_changed_work(struct work_struct *work)
@@ -2982,6 +3017,62 @@ static int virtnet_validate(struct virtio_device *vdev)
return 0;
}
+static void _remove_vq_common(struct virtnet_info *vi)
+{
+ vi->vdev->config->reset(vi->vdev);
+
+ /* Free unused buffers in both send and recv, if any. */
+ free_unused_bufs(vi);
+
+ _free_receive_bufs(vi);
+
+ free_receive_page_frags(vi);
+
+ virtnet_del_vqs(vi);
+}
+
+static int _virtnet_reset(struct virtnet_info *vi)
+{
+ struct virtio_device *vdev = vi->vdev;
+ int ret;
+
+ virtio_config_disable(vdev);
+ vdev->failed = vdev->config->get_status(vdev) &
VIRTIO_CONFIG_S_FAILED;
+
+ virtnet_freeze_down(vdev);
+ _remove_vq_common(vi);
+
+ virtio_add_status(vdev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
+ virtio_add_status(vdev, VIRTIO_CONFIG_S_DRIVER);
+
+ ret = virtio_finalize_features(vdev);
+ if (ret)
+ goto err;
+
+ ret = virtnet_restore_up(vdev);
+ if (ret)
+ goto err;
+
+ ret = _virtnet_set_queues(vi, vi->curr_queue_pairs);
+ if (ret)
+ goto err;
+
+ virtio_add_status(vdev, VIRTIO_CONFIG_S_DRIVER_OK);
+ virtio_config_enable(vdev);
+ return 0;
+err:
+ virtio_add_status(vdev, VIRTIO_CONFIG_S_FAILED);
+ return ret;
+}
+
+static void virtnet_reset(struct work_struct *work)
+{
+ struct virtnet_info *vi + container_of(work, struct virtnet_info,
reset_work);
+
+ _virtnet_reset(vi);
+}
+
static int virtnet_probe(struct virtio_device *vdev)
{
int i, err = -ENOMEM;
@@ -3011,6 +3102,7 @@ static int virtnet_probe(struct virtio_device *vdev)
dev->netdev_ops = &virtnet_netdev;
dev->features = NETIF_F_HIGHDMA;
+ dev->watchdog_timeo = 5 * HZ;
dev->ethtool_ops = &virtnet_ethtool_ops;
SET_NETDEV_DEV(dev, &vdev->dev);
@@ -3068,6 +3160,7 @@ static int virtnet_probe(struct virtio_device *vdev)
vdev->priv = vi;
INIT_WORK(&vi->config_work, virtnet_config_changed_work);
+ INIT_WORK(&vi->reset_work, virtnet_reset);
/* If we can receive ANY GSO packets, we must allocate large ones. */
if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
--
2.17.1