[PATCH net-next v1 5/5] net: lan743x: add byte queue limits support
flat view
HOTtoday
From: Chris Babroski <hidden>
Date: 2026-10-15 15:02:59
Also in:
lkml
Subsystem:
microchip lan743x ethernet driver, networking drivers, the rest · Maintainers:
Bryan Whitehead, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Report the bytes queued to and completed by each TX ring to BQL. Besides limiting how much data sits in the TX ring, this lets the stack stop a queue once the bytes in flight exceed the BQL limit. Without it, a queue is only stopped when its 128 entry ring is full, and the TX watchdog only looks at stopped queues. With light traffic it can take tens of seconds after a TX hang to fill the ring, before the watchdog timeout even starts counting. lan743x_tx_close() frees pending descriptors without completing them, so reset the BQL state there. Assisted-by: LLM Signed-off-by: Chris Babroski <redacted> --- drivers/net/ethernet/microchip/lan743x_main.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)
diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
index 2545a846478d..7739fa49fc44 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.c
+++ b/drivers/net/ethernet/microchip/lan743x_main.c@@ -1708,10 +1708,23 @@ static int lan743x_tx_next_index(struct lan743x_tx *tx, int index) static void lan743x_tx_release_completed_descriptors(struct lan743x_tx *tx) { + struct lan743x_tx_buffer_info *buffer_info; + unsigned int bytes = 0; + unsigned int pkts = 0; + while (le32_to_cpu(*tx->head_cpu_ptr) != (tx->last_head)) { + buffer_info = &tx->buffer_info[tx->last_head]; + if (buffer_info->skb) { + bytes += buffer_info->skb->len; + pkts++; + } lan743x_tx_release_desc(tx, tx->last_head, false); tx->last_head = lan743x_tx_next_index(tx, tx->last_head); } + + netdev_tx_completed_queue(netdev_get_tx_queue(tx->adapter->netdev, + tx->channel_number), + pkts, bytes); } static void lan743x_tx_release_all_descriptors(struct lan743x_tx *tx)
@@ -2003,6 +2016,10 @@ static void lan743x_tx_frame_end(struct lan743x_tx *tx, if (ignore_sync) buffer_info->flags |= TX_BUFFER_INFO_FLAG_IGNORE_SYNC; + netdev_tx_sent_queue(netdev_get_tx_queue(adapter->netdev, + tx->channel_number), + skb->len); + tx_descriptor = &tx->ring_cpu_ptr[tx->frame_tail]; tx_descriptor->data0 = cpu_to_le32(tx->frame_data0); tx->frame_tail = lan743x_tx_next_index(tx, tx->frame_tail);
@@ -2276,6 +2293,8 @@ static void lan743x_tx_close(struct lan743x_tx *tx) 0, 1000, 20000, 100); lan743x_tx_release_all_descriptors(tx); + netdev_tx_reset_queue(netdev_get_tx_queue(adapter->netdev, + tx->channel_number)); tx->rqd_descriptors = 0;
--
2.34.1