Re: [PATCH RFC net-next 1/2] drivers: net: virtio_net: Add tx_timeout stats field

From: Julian Wiedmann
Date: Mon Oct 07 2019 - 10:15:28 EST


On 06.10.19 20:45, jcfaracco@xxxxxxxxx wrote:
> From: Julio Faracco <jcfaracco@xxxxxxxxx>
>
> For debug purpose of TX timeout events, a tx_timeout entry was added to
> monitor this special case: when dev_watchdog identifies a tx_timeout and
> throw an exception. We can both consider this event as an error, but
> driver should report as a tx_timeout statistic.
>

Hi Julio,
dev_watchdog() updates txq->trans_timeout, why isn't that sufficient?


> Signed-off-by: Julio Faracco <jcfaracco@xxxxxxxxx>
> Signed-off-by: Daiane Mendes <dnmendes76@xxxxxxxxx>
> Cc: Jason Wang <jasowang@xxxxxxxxxx>
> ---
> drivers/net/virtio_net.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 4f3de0ac8b0b..27f9b212c9f5 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[] = {
> @@ -1721,7 +1723,7 @@ 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 +1731,7 @@ 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 +1746,7 @@ 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;
>