[PATCH 3/4] eventdev: have ethernet Tx adapter appropriately report idle

[Mattias Rönnblom]

Update the Event Ethernet Tx Adapter's service function to report as
idle (i.e., return -EAGAIN) in case no events were dequeued from the
event device and no Ethernet frames were sent out on the wire.

Signed-off-by: Mattias Rönnblom <mattias.ronnb...@ericsson.com>
---
 lib/eventdev/rte_event_eth_tx_adapter.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/lib/eventdev/rte_event_eth_tx_adapter.c 
b/lib/eventdev/rte_event_eth_tx_adapter.c
index 7f7d86f683..c2a848103b 100644
--- a/lib/eventdev/rte_event_eth_tx_adapter.c
+++ b/lib/eventdev/rte_event_eth_tx_adapter.c
@@ -639,6 +639,7 @@ txa_service_func(void *args)
        struct txa_service_data *txa = args;
        uint8_t dev_id;
        uint8_t port;
+       int ret = -EAGAIN;
        uint16_t n;
        uint32_t nb_tx, max_nb_tx;
        struct rte_event ev[TXA_BATCH_SIZE];
@@ -648,10 +649,10 @@ txa_service_func(void *args)
        port = txa->port_id;
 
        if (txa->nb_queues == 0)
-               return 0;
+               return ret;
 
        if (!rte_spinlock_trylock(&txa->tx_lock))
-               return 0;
+               return ret;
 
        for (nb_tx = 0; nb_tx < max_nb_tx; nb_tx += n) {
 
@@ -659,6 +660,7 @@ txa_service_func(void *args)
                if (!n)
                        break;
                txa_service_tx(txa, ev, n);
+               ret = 0;
        }
 
        if ((txa->loop_cnt++ & (TXA_FLUSH_THRESHOLD - 1)) == 0) {
@@ -692,10 +694,13 @@ txa_service_func(void *args)
                        }
                }
 
-               txa->stats.tx_packets += nb_tx;
+               if (likely(nb_tx > 0)) {
+                       txa->stats.tx_packets += nb_tx;
+                       ret = 0;
+               }
        }
        rte_spinlock_unlock(&txa->tx_lock);
-       return 0;
+       return ret;
 }
 
 static int
-- 
2.34.1