On 6/26/2023 2:48 PM, souradeep chakrabarti wrote:
From: Souradeep Chakrabarti schakrabarti@linux.microsoft.com
This patch addresses the VF unload issue, where mana_dealloc_queues() gets stuck in infinite while loop, because of host unresponsiveness. It adds a timeout in the while loop, to fix it.
Fixes: ca9c54d2d6a5ab2430c4eda364c77125d62e5e0f (net: mana: Add a driver for Microsoft Azure Network Adapter) Signed-off-by: Souradeep Chakrabarti schakrabarti@linux.microsoft.com
V2 -> V3:
- Splitted the patch in two parts.
- Removed the unnecessary braces from mana_dealloc_queues().
drivers/net/ethernet/microsoft/mana/mana_en.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index d907727c7b7a..cb5c43c3c47e 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_en.c +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c @@ -2329,7 +2329,10 @@ 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) @@ -2348,13 +2351,25 @@ static int mana_dealloc_queues(struct net_device *ndev) * * Drain all the in-flight TX packets */
- 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);}- }
Can we combine these 2 loops into 1 something like this ?
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)) { if (time_before(jiffies, timeout)) { usleep_range(1000, 2000); } else { 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. */