Looks good. Thanks for posting this change!
Acked-by: Jay Jayatheerthan <jay.jayatheert...@intel.com>
> -----Original Message-----
> From: Mattias Rönnblom <mattias.ronnb...@ericsson.com>
> Sent: Wednesday, November 10, 2021 4:44 PM
> To: jerinjac...@gmail.com; Jayatheerthan, Jay <jay.jayatheert...@intel.com>;
> Kundapura, Ganapati
> <ganapati.kundap...@intel.com>; jer...@marvell.com
> Cc: dev @ dpdk . org <dev@dpdk.org>; mattias.ronnblom
> <mattias.ronnb...@ericsson.com>
> Subject: [PATCH v2] eventdev: fix Rx adapter stalls on event device
> backpressure
>
> In the Eventdev Ethernet RX Adapter, correctly handle the case where
> the circular enqueue buffer head and last index point to the same
> element.
>
> This bug may be triggered in case there is backpressure from the event
> device to the RX adapter.
>
> v2:
> * Corrected bug description
>
> Fixes: 8113fd15e229 ("eventdev/eth_rx: make enqueue buffer circular")
> Cc: ganapati.kundap...@intel.com
>
> Signed-off-by: Mattias Rönnblom <mattias.ronnb...@ericsson.com>
> ---
> lib/eventdev/rte_event_eth_rx_adapter.c | 22 ++++++++++++++--------
> 1 file changed, 14 insertions(+), 8 deletions(-)
>
> diff --git a/lib/eventdev/rte_event_eth_rx_adapter.c
> b/lib/eventdev/rte_event_eth_rx_adapter.c
> index 56318b5a6f..809416d9b7 100644
> --- a/lib/eventdev/rte_event_eth_rx_adapter.c
> +++ b/lib/eventdev/rte_event_eth_rx_adapter.c
> @@ -777,19 +777,25 @@ rxa_flush_event_buffer(struct event_eth_rx_adapter
> *rx_adapter,
> struct eth_event_enqueue_buffer *buf,
> struct rte_event_eth_rx_adapter_stats *stats)
> {
> - uint16_t count = buf->last ? buf->last - buf->head : buf->count;
> + uint16_t count = buf->count;
> + uint16_t n = 0;
>
> if (!count)
> return 0;
>
> - uint16_t n = rte_event_enqueue_new_burst(rx_adapter->eventdev_id,
> - rx_adapter->event_port_id,
> - &buf->events[buf->head],
> - count);
> - if (n != count)
> - stats->rx_enq_retry++;
> + if (buf->last)
> + count = buf->last - buf->head;
> +
> + if (count) {
> + n = rte_event_enqueue_new_burst(rx_adapter->eventdev_id,
> + rx_adapter->event_port_id,
> + &buf->events[buf->head],
> + count);
> + if (n != count)
> + stats->rx_enq_retry++;
>
> - buf->head += n;
> + buf->head += n;
> + }
>
> if (buf->last && n == count) {
> uint16_t n1;
> --
> 2.25.1
