releases/6.4.7/igc-avoid-transmit-queue-timeout-for-xdp.patch

From df3cfe2aab8fbc415d4ae2485e94aa3caa55fbed Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Wed, 12 Apr 2023 09:36:11 +0200
Subject: igc: Avoid transmit queue timeout for XDP

From: Kurt Kanzenbach <kurt@linutronix.de>

[ Upstream commit 95b681485563c64585de78662ee52d06b7fa47d9 ]

High XDP load triggers the netdev watchdog:

|NETDEV WATCHDOG: enp3s0 (igc): transmit queue 2 timed out

The reason is the Tx queue transmission start (txq->trans_start) is not updated
in XDP code path. Therefore, add it for all XDP transmission functions.

Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Stable-dep-of: 78adb4bcf99e ("igc: Prevent garbled TX queue with XDP ZEROCOPY")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/intel/igc/igc_main.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 44aa4342cbbb5..ef4ea46442f21 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -2417,6 +2417,8 @@ static int igc_xdp_xmit_back(struct igc_adapter *adapter, struct xdp_buff *xdp)
 	nq = txring_txq(ring);
 
 	__netif_tx_lock(nq, cpu);
+	/* Avoid transmit queue timeout since we share it with the slow path */
+	txq_trans_cond_update(nq);
 	res = igc_xdp_init_tx_descriptor(ring, xdpf);
 	__netif_tx_unlock(nq);
 	return res;
@@ -2833,6 +2835,9 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring)
 
 	__netif_tx_lock(nq, cpu);
 
+	/* Avoid transmit queue timeout since we share it with the slow path */
+	txq_trans_cond_update(nq);
+
 	budget = igc_desc_unused(ring);
 
 	while (xsk_tx_peek_desc(pool, &xdp_desc) && budget--) {
@@ -6385,6 +6390,9 @@ static int igc_xdp_xmit(struct net_device *dev, int num_frames,
 
 	__netif_tx_lock(nq, cpu);
 
+	/* Avoid transmit queue timeout since we share it with the slow path */
+	txq_trans_cond_update(nq);
+
 	drops = 0;
 	for (i = 0; i < num_frames; i++) {
 		int err;
-- 
2.39.2