efx_enqueue_skb() can push new buffers for the xmit_more functionality.
We must stops the TX queue before this or else the TX queue does not get
restarted and we get a netdev watchdog.
In the error handling we may now need to unwind more than 1 packet, and
we may need to push the new buffers onto the partner queue.
Fixes: e9117e5099ea ("sfc: Firmware-Assisted TSO version 2")
Reported-by: Jarod Wilson <ja...@redhat.com>
Signed-off-by: Martin Habets <mhab...@solarflare.com>
---
Dave, could you please also queue up this patch for stable?
drivers/net/ethernet/sfc/tx.c | 31 +++++++++++++++++++++++--------
1 file changed, 23 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ethernet/sfc/tx.c b/drivers/net/ethernet/sfc/tx.c
index cece961f2e82..17e0697f42d5 100644
--- a/drivers/net/ethernet/sfc/tx.c
+++ b/drivers/net/ethernet/sfc/tx.c
@@ -435,17 +435,18 @@ static int efx_tx_map_data(struct efx_tx_queue *tx_queue,
struct sk_buff *skb,
} while (1);
}
-/* Remove buffers put into a tx_queue. None of the buffers must have
- * an skb attached.
+/* Remove buffers put into a tx_queue for the current packet.
+ * None of the buffers must have an skb attached.
*/
-static void efx_enqueue_unwind(struct efx_tx_queue *tx_queue)
+static void efx_enqueue_unwind(struct efx_tx_queue *tx_queue,
+ unsigned int insert_count)
{
struct efx_tx_buffer *buffer;
unsigned int bytes_compl = 0;
unsigned int pkts_compl = 0;
/* Work backwards until we hit the original insert pointer value */
- while (tx_queue->insert_count != tx_queue->write_count) {
+ while (tx_queue->insert_count != insert_count) {
--tx_queue->insert_count;
buffer = __efx_tx_queue_get_insert_buffer(tx_queue);
efx_dequeue_buffer(tx_queue, buffer, &pkts_compl, &bytes_compl);
@@ -504,6 +505,8 @@ static int efx_tx_tso_fallback(struct efx_tx_queue
*tx_queue,
*/
netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb)
{
+ unsigned int old_insert_count = tx_queue->insert_count;
+ bool xmit_more = skb->xmit_more;
bool data_mapped = false;
unsigned int segments;
unsigned int skb_len;
@@ -553,8 +556,10 @@ netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue,
struct sk_buff *skb)
/* Update BQL */
netdev_tx_sent_queue(tx_queue->core_txq, skb_len);
+ efx_tx_maybe_stop_queue(tx_queue);
+
/* Pass off to hardware */
- if (!skb->xmit_more || netif_xmit_stopped(tx_queue->core_txq)) {
+ if (!xmit_more || netif_xmit_stopped(tx_queue->core_txq)) {
struct efx_tx_queue *txq2 = efx_tx_queue_partner(tx_queue);
/* There could be packets left on the partner queue if those
@@ -577,14 +582,24 @@ netdev_tx_t efx_enqueue_skb(struct efx_tx_queue
*tx_queue, struct sk_buff *skb)
tx_queue->tx_packets++;
}
- efx_tx_maybe_stop_queue(tx_queue);
-
return NETDEV_TX_OK;
err:
- efx_enqueue_unwind(tx_queue);
+ efx_enqueue_unwind(tx_queue, old_insert_count);
dev_kfree_skb_any(skb);
+
+ /* If we're not expecting another transmit and we had something to push
+ * on this queue or a partner queue then we need to push here to get the
+ * previous packets out.
+ */
+ if (!xmit_more) {
+ struct efx_tx_queue *txq2 = efx_tx_queue_partner(tx_queue);
+
+ if (txq2->xmit_more_available)
+ efx_nic_push_buffers(txq2);
+ }
+
return NETDEV_TX_OK;
}
