Re: [dpdk-dev] [PATCH / RFC ] ethdev: Allow rte_eth_dev_configure with zero RX/TX queues

["Simon Kågström" <simon.kagstrom@netinsight.net>]

On 2016-05-16 14:43, Pattan, Reshma wrote:
>>> This was added to allow devices,  at least with one direction (RX/TX)
>> supported. As, devices with both directions disabled doesn't make  sense right?
>>
>> Well, not for running them, no. But this is a part of the shutdown procedure
>> between tests (I should have been more clear I guess).
> 
> Yes I understood this. But I am not sure if you can use rte_eth_dev_configure(port, 0, 0) to free the resources.
> Can you check if you can use rte_eth_dev_rx_queue_stop/ rte_eth_dev_tx_queue_stop to achieve the same, because they do take care of
> releasing mbufs, but doesn't free the queue's sw-ring and queue.

But isn't that very strange behavior. Aren't the descriptor rings
allocated in rx_queue_setup()? If so, the sequence

  rx_queue_stop(); // Release buffers
  rx_queue_start();

would leave the descriptor ring empty after start, i.e., not able to
receive data.

// Simon