[PATCH 2/2] ethdev: return 0 from dummy queue count

[Stephen Hemminger]

On Tue, 16 Jun 2026 11:42:58 +0200
Maxime Leroy <maxime at leroys.fr> wrote:

> The dummy rx_queue_count/tx_queue_count callback returned -ENOTSUP. On a
> port that is not started (freshly allocated, or stopped once the fast-path
> ops are reset to dummies) there are no packets queued, so the truthful
> answer is 0, not an error: querying the count is not an unsupported
> operation. This also matches the dummy Rx/Tx burst, which reports 0
> packets.
> 
> A poll-mode worker checking rte_eth_rx_queue_count() across a concurrent
> port stop then sees an empty queue instead of a negative error.
> 
> Fixes: 066f3d9cc21c ("ethdev: remove callback checks from fast path")
> Cc: stable at dpdk.org
> 
> Suggested-by: Stephen Hemminger <stephen at networkplumber.org>
> Signed-off-by: Maxime Leroy <maxime at leroys.fr>

Acked-by: Stephen Hemminger <stephen at networkplumber.org>