[PATCH 5.7 140/265] ionic: tame the watchdog timer on reconfig

From: Sasha Levin
Date: Mon Jun 29 2020 - 17:52:50 EST


From: Shannon Nelson <snelson@xxxxxxxxxxx>

[ Upstream commit b59eabd23ee53e8c3492602722e1697f9a2f63ad ]

Even with moving netif_tx_disable() to an earlier point when
taking down the queues for a reconfiguration, we still end
up with the occasional netdev watchdog Tx Timeout complaint.
The old method of using netif_trans_update() works fine for
queue 0, but has no effect on the remaining queues. Using
netif_device_detach() allows us to signal to the watchdog to
ignore us for the moment.

Fixes: beead698b173 ("ionic: Add the basic NDO callbacks for netdev support")
Signed-off-by: Shannon Nelson <snelson@xxxxxxxxxxx>
Acked-by: Jonathan Toppins <jtoppins@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/pensando/ionic/ionic_lif.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_lif.c b/drivers/net/ethernet/pensando/ionic/ionic_lif.c
index 2729b0bb12739..790d4854b8ef5 100644
--- a/drivers/net/ethernet/pensando/ionic/ionic_lif.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_lif.c
@@ -1682,8 +1682,8 @@ static void ionic_stop_queues(struct ionic_lif *lif)
if (!test_and_clear_bit(IONIC_LIF_F_UP, lif->state))
return;

- ionic_txrx_disable(lif);
netif_tx_disable(lif->netdev);
+ ionic_txrx_disable(lif);
}

int ionic_stop(struct net_device *netdev)
@@ -1949,18 +1949,19 @@ int ionic_reset_queues(struct ionic_lif *lif)
bool running;
int err = 0;

- /* Put off the next watchdog timeout */
- netif_trans_update(lif->netdev);
-
err = ionic_wait_for_bit(lif, IONIC_LIF_F_QUEUE_RESET);
if (err)
return err;

running = netif_running(lif->netdev);
- if (running)
+ if (running) {
+ netif_device_detach(lif->netdev);
err = ionic_stop(lif->netdev);
- if (!err && running)
+ }
+ if (!err && running) {
ionic_open(lif->netdev);
+ netif_device_attach(lif->netdev);
+ }

clear_bit(IONIC_LIF_F_QUEUE_RESET, lif->state);

--
2.25.1