Add a tx queue stop and wake counters, they are useful for debugging. $ ethtool -S ens5f2 | grep 'tx_stop\|tx_wake' ... tx_queue_1_tx_stop: 16726 tx_queue_1_tx_wake: 16726 ... tx_queue_8_tx_stop: 1500110 tx_queue_8_tx_wake: 1500110
Signed-off-by: Daniel Jurgens <dani...@nvidia.com> Reviewed-by: Parav Pandit <pa...@nvidia.com> --- drivers/net/virtio_net.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 3cb8aa193884..7e3c31ceaf7e 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -88,6 +88,8 @@ struct virtnet_sq_stats { u64_stats_t xdp_tx_drops; u64_stats_t kicks; u64_stats_t tx_timeouts; + u64_stats_t tx_stop; + u64_stats_t tx_wake; }; struct virtnet_rq_stats { @@ -112,6 +114,8 @@ static const struct virtnet_stat_desc virtnet_sq_stats_desc[] = { { "xdp_tx_drops", VIRTNET_SQ_STAT(xdp_tx_drops) }, { "kicks", VIRTNET_SQ_STAT(kicks) }, { "tx_timeouts", VIRTNET_SQ_STAT(tx_timeouts) }, + { "tx_stop", VIRTNET_SQ_STAT(tx_stop) }, + { "tx_wake", VIRTNET_SQ_STAT(tx_wake) }, }; static const struct virtnet_stat_desc virtnet_rq_stats_desc[] = { @@ -843,6 +847,9 @@ static void check_sq_full_and_disable(struct virtnet_info *vi, */ if (sq->vq->num_free < 2+MAX_SKB_FRAGS) { netif_stop_subqueue(dev, qnum); + u64_stats_update_begin(&sq->stats.syncp); + u64_stats_inc(&sq->stats.tx_stop); + u64_stats_update_end(&sq->stats.syncp); if (use_napi) { if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) virtqueue_napi_schedule(&sq->napi, sq->vq); @@ -851,6 +858,9 @@ static void check_sq_full_and_disable(struct virtnet_info *vi, free_old_xmit_skbs(sq, false); if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) { netif_start_subqueue(dev, qnum); + u64_stats_update_begin(&sq->stats.syncp); + u64_stats_inc(&sq->stats.tx_wake); + u64_stats_update_end(&sq->stats.syncp); virtqueue_disable_cb(sq->vq); } } @@ -2163,8 +2173,14 @@ static void virtnet_poll_cleantx(struct receive_queue *rq) free_old_xmit_skbs(sq, true); } while (unlikely(!virtqueue_enable_cb_delayed(sq->vq))); - if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS) + if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS) { + if (netif_tx_queue_stopped(txq)) { + u64_stats_update_begin(&sq->stats.syncp); + u64_stats_inc(&sq->stats.tx_wake); + u64_stats_update_end(&sq->stats.syncp); + } netif_tx_wake_queue(txq); + } __netif_tx_unlock(txq); } @@ -2310,8 +2326,14 @@ static int virtnet_poll_tx(struct napi_struct *napi, int budget) virtqueue_disable_cb(sq->vq); free_old_xmit_skbs(sq, true); - if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS) + if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS) { + if (netif_tx_queue_stopped(txq)) { + u64_stats_update_begin(&sq->stats.syncp); + u64_stats_inc(&sq->stats.tx_wake); + u64_stats_update_end(&sq->stats.syncp); + } netif_tx_wake_queue(txq); + } opaque = virtqueue_enable_cb_prepare(sq->vq); -- 2.42.0