Re: [PATCH net-next] net: cadence: macb: Implement BQL

[Sean Anderson <sean.anderson@linux.dev>]

On 2/18/25 20:57, Jakub Kicinski wrote:
> On Fri, 14 Feb 2025 16:16:43 -0500 Sean Anderson wrote:
>> diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
>> index 48496209fb16..63c65b4bb348 100644
>> --- a/drivers/net/ethernet/cadence/macb_main.c
>> +++ b/drivers/net/ethernet/cadence/macb_main.c
>> @@ -1081,6 +1081,9 @@ static void macb_tx_error_task(struct work_struct *work)
>>  						      tx_error_task);
>>  	bool			halt_timeout = false;
>>  	struct macb		*bp = queue->bp;
>> +	u32			queue_index = queue - bp->queues;
> 
> nit: breaking reverse xmas tree here

It has to happen here since bp isn't available earlier.

>> +	u32			packets = 0;
>> +	u32			bytes = 0;
>>  	struct macb_tx_skb	*tx_skb;
>>  	struct macb_dma_desc	*desc;
>>  	struct sk_buff		*skb;
> 
> 
>> @@ -3019,6 +3033,7 @@ static int macb_close(struct net_device *dev)
>>  	netif_tx_stop_all_queues(dev);
>>  
>>  	for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) {
>> +		netdev_tx_reset_queue(netdev_get_tx_queue(dev, q));
>>  		napi_disable(&queue->napi_rx);
>>  		napi_disable(&queue->napi_tx);
> 
> I think you should reset after napi_disable()? 
> Lest NAPI runs after the reset and tries to complete on an empty queue..

OK.

--Sean