From: Souradeep Chakrabarti schakrabarti@linux.microsoft.com
When unloading the MANA driver, mana_dealloc_queues() waits for the MANA hardware to complete any inflight packets and set the pending send count to zero. But if the hardware has failed, mana_dealloc_queues() could wait forever.
Fix this by adding a timeout to the wait. Set the timeout to 120 seconds, which is a somewhat arbitrary value that is more than long enough for functional hardware to complete any sends.
Signed-off-by: Souradeep Chakrabarti schakrabarti@linux.microsoft.com --- V3 -> V4: * Fixed the commit message to describe the context. * Removed the vf_unload_timeout, as it is not required. --- drivers/net/ethernet/microsoft/mana/mana_en.c | 26 ++++++++++++++++--- 1 file changed, 23 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index a499e460594b..d26f1da70411 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_en.c +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c @@ -2346,7 +2346,10 @@ static int mana_dealloc_queues(struct net_device *ndev) { struct mana_port_context *apc = netdev_priv(ndev); struct gdma_dev *gd = apc->ac->gdma_dev; + unsigned long timeout; struct mana_txq *txq; + struct sk_buff *skb; + struct mana_cq *cq; int i, err;
if (apc->port_is_up) @@ -2363,15 +2366,32 @@ static int mana_dealloc_queues(struct net_device *ndev) * to false, but it doesn't matter since mana_start_xmit() drops any * new packets due to apc->port_is_up being false. * - * Drain all the in-flight TX packets + * Drain all the in-flight TX packets. + * A timeout of 120 seconds for all the queues is used. + * This will break the while loop when h/w is not responding. + * This value of 120 has been decided here considering max + * number of queues. */ + + timeout = jiffies + 120 * HZ; for (i = 0; i < apc->num_queues; i++) { txq = &apc->tx_qp[i].txq; - - while (atomic_read(&txq->pending_sends) > 0) + while (atomic_read(&txq->pending_sends) > 0 && + time_before(jiffies, timeout)) { usleep_range(1000, 2000); + } }
+ for (i = 0; i < apc->num_queues; i++) { + txq = &apc->tx_qp[i].txq; + cq = &apc->tx_qp[i].tx_cq; + while (atomic_read(&txq->pending_sends)) { + skb = skb_dequeue(&txq->pending_skbs); + mana_unmap_skb(skb, apc); + napi_consume_skb(skb, cq->budget); + atomic_sub(1, &txq->pending_sends); + } + } /* We're 100% sure the queues can no longer be woken up, because * we're sure now mana_poll_tx_cq() can't be running. */