netdev-dpdk: Free mbufs in bulk.

rte_pktmbuf_free_bulk() function was introduced in 19.11 and became stable in 21.11. Use it to free arrays of mbufs instead of freeing packets one by one. In simple V2V testing with 64B packets, 2 PMD threads and bidirectional traffic this change improves performance by 3.5 - 4.5 %. Reviewed-by: David Marchand <[email protected]> Acked-by: Kevin Traynor <[email protected]> Signed-off-by: Ilya Maximets <[email protected]>
nevalosa · Jan 27, 2023 · ebaee44 · ebaee44
1 parent b7f5401
commit ebaee44
Showing 1 changed file with 3 additions and 10 deletions.
diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c
@@ -2287,13 +2287,8 @@ netdev_dpdk_eth_tx_burst(struct netdev_dpdk *dev, int qid,
     }
 
     if (OVS_UNLIKELY(nb_tx != cnt)) {
-        /* Free buffers, which we couldn't transmit, one at a time (each
-         * packet could come from a different mempool) */
-        int i;
-
-        for (i = nb_tx; i < cnt; i++) {
-            rte_pktmbuf_free(pkts[i]);
-        }
+        /* Free buffers, which we couldn't transmit. */
+        rte_pktmbuf_free_bulk(&pkts[nb_tx], cnt - nb_tx);
     }
 
     return cnt - nb_tx;
@@ -2769,9 +2764,7 @@ netdev_dpdk_vhost_send(struct netdev *netdev, int qid,
     }
 
     pkts = (struct rte_mbuf **) batch->packets;
-    for (int i = 0; i < vhost_batch_cnt; i++) {
-        rte_pktmbuf_free(pkts[i]);
-    }
+    rte_pktmbuf_free_bulk(pkts, vhost_batch_cnt);
 
     return 0;
 }