port: add ethdev writer nodrop

When ethdev_writer_nodrop port fails to send data, it tries to resend.
Operation is aborted when maximum number of retries is reached.

Signed-off-by: Maciej Gajdzica <maciejx.t.gajdzica@intel.com>
Acked-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>

diff --git a/lib/librte_port/rte_port_ethdev.c b/lib/librte_port/rte_port_ethdev.c
index 55ed829..39ed72d 100644 (file)
--- a/lib/librte_port/rte_port_ethdev.c
+++ b/lib/librte_port/rte_port_ethdev.c
@@ -31,6 +31,7 @@
  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include <string.h>
+#include <stdint.h>
 
 #include <rte_mbuf.h>
 #include <rte_ethdev.h>
@@ -240,6 +241,180 @@ rte_port_ethdev_writer_free(void *port)
        return 0;
 }
 
+/*
+ * Port ETHDEV Writer Nodrop
+ */
+struct rte_port_ethdev_writer_nodrop {
+       struct rte_mbuf *tx_buf[2 * RTE_PORT_IN_BURST_SIZE_MAX];
+       uint32_t tx_burst_sz;
+       uint16_t tx_buf_count;
+       uint64_t bsz_mask;
+       uint64_t n_retries;
+       uint16_t queue_id;
+       uint8_t port_id;
+};
+
+static void *
+rte_port_ethdev_writer_nodrop_create(void *params, int socket_id)
+{
+       struct rte_port_ethdev_writer_nodrop_params *conf =
+                       (struct rte_port_ethdev_writer_nodrop_params *) params;
+       struct rte_port_ethdev_writer_nodrop *port;
+
+       /* Check input parameters */
+       if ((conf == NULL) ||
+               (conf->tx_burst_sz == 0) ||
+               (conf->tx_burst_sz > RTE_PORT_IN_BURST_SIZE_MAX) ||
+               (!rte_is_power_of_2(conf->tx_burst_sz))) {
+               RTE_LOG(ERR, PORT, "%s: Invalid input parameters\n", __func__);
+               return NULL;
+       }
+
+       /* Memory allocation */
+       port = rte_zmalloc_socket("PORT", sizeof(*port),
+                       RTE_CACHE_LINE_SIZE, socket_id);
+       if (port == NULL) {
+               RTE_LOG(ERR, PORT, "%s: Failed to allocate port\n", __func__);
+               return NULL;
+       }
+
+       /* Initialization */
+       port->port_id = conf->port_id;
+       port->queue_id = conf->queue_id;
+       port->tx_burst_sz = conf->tx_burst_sz;
+       port->tx_buf_count = 0;
+       port->bsz_mask = 1LLU << (conf->tx_burst_sz - 1);
+
+       /*
+        * When n_retries is 0 it means that we should wait for every packet to
+        * send no matter how many retries should it take. To limit number of
+        * branches in fast path, we use UINT64_MAX instead of branching.
+        */
+       port->n_retries = (conf->n_retries == 0) ? UINT64_MAX : conf->n_retries;
+
+       return port;
+}
+
+static inline void
+send_burst_nodrop(struct rte_port_ethdev_writer_nodrop *p)
+{
+       uint32_t nb_tx = 0, i;
+
+       nb_tx = rte_eth_tx_burst(p->port_id, p->queue_id, p->tx_buf,
+                       p->tx_buf_count);
+
+       /* We sent all the packets in a first try */
+       if (nb_tx >= p->tx_buf_count)
+               return;
+
+       for (i = 0; i < p->n_retries; i++) {
+               nb_tx += rte_eth_tx_burst(p->port_id, p->queue_id,
+                                                        p->tx_buf + nb_tx, p->tx_buf_count - nb_tx);
+
+               /* We sent all the packets in more than one try */
+               if (nb_tx >= p->tx_buf_count)
+                       return;
+       }
+
+       /* We didn't send the packets in maximum allowed attempts */
+       for ( ; nb_tx < p->tx_buf_count; nb_tx++)
+               rte_pktmbuf_free(p->tx_buf[nb_tx]);
+
+       p->tx_buf_count = 0;
+}
+
+static int
+rte_port_ethdev_writer_nodrop_tx(void *port, struct rte_mbuf *pkt)
+{
+       struct rte_port_ethdev_writer_nodrop *p =
+               (struct rte_port_ethdev_writer_nodrop *) port;
+
+       p->tx_buf[p->tx_buf_count++] = pkt;
+       if (p->tx_buf_count >= p->tx_burst_sz)
+               send_burst_nodrop(p);
+
+       return 0;
+}
+
+static int
+rte_port_ethdev_writer_nodrop_tx_bulk(void *port,
+               struct rte_mbuf **pkts,
+               uint64_t pkts_mask)
+{
+       struct rte_port_ethdev_writer_nodrop *p =
+               (struct rte_port_ethdev_writer_nodrop *) port;
+
+       uint32_t bsz_mask = p->bsz_mask;
+       uint32_t tx_buf_count = p->tx_buf_count;
+       uint64_t expr = (pkts_mask & (pkts_mask + 1)) |
+                       ((pkts_mask & bsz_mask) ^ bsz_mask);
+
+       if (expr == 0) {
+               uint64_t n_pkts = __builtin_popcountll(pkts_mask);
+               uint32_t n_pkts_ok;
+
+               if (tx_buf_count)
+                       send_burst_nodrop(p);
+
+               n_pkts_ok = rte_eth_tx_burst(p->port_id, p->queue_id, pkts,
+                       n_pkts);
+
+               if (n_pkts_ok >= n_pkts)
+                       return 0;
+
+               /*
+                * If we didnt manage to send all packets in single burst, move
+                * remaining packets to the buffer and call send burst.
+                */
+               for (; n_pkts_ok < n_pkts; n_pkts_ok++) {
+                       struct rte_mbuf *pkt = pkts[n_pkts_ok];
+                       p->tx_buf[p->tx_buf_count++] = pkt;
+               }
+               send_burst_nodrop(p);
+       } else {
+               for ( ; pkts_mask; ) {
+                       uint32_t pkt_index = __builtin_ctzll(pkts_mask);
+                       uint64_t pkt_mask = 1LLU << pkt_index;
+                       struct rte_mbuf *pkt = pkts[pkt_index];
+
+                       p->tx_buf[tx_buf_count++] = pkt;
+                       pkts_mask &= ~pkt_mask;
+               }
+
+               p->tx_buf_count = tx_buf_count;
+               if (tx_buf_count >= p->tx_burst_sz)
+                       send_burst_nodrop(p);
+       }
+
+       return 0;
+}
+
+static int
+rte_port_ethdev_writer_nodrop_flush(void *port)
+{
+       struct rte_port_ethdev_writer_nodrop *p =
+               (struct rte_port_ethdev_writer_nodrop *) port;
+
+       if (p->tx_buf_count > 0)
+               send_burst_nodrop(p);
+
+       return 0;
+}
+
+static int
+rte_port_ethdev_writer_nodrop_free(void *port)
+{
+       if (port == NULL) {
+               RTE_LOG(ERR, PORT, "%s: Port is NULL\n", __func__);
+               return -EINVAL;
+       }
+
+       rte_port_ethdev_writer_nodrop_flush(port);
+       rte_free(port);
+
+       return 0;
+}
+
 /*
  * Summary of port operations
  */
@@ -256,3 +431,11 @@ struct rte_port_out_ops rte_port_ethdev_writer_ops = {
        .f_tx_bulk = rte_port_ethdev_writer_tx_bulk,
        .f_flush = rte_port_ethdev_writer_flush,
 };
+
+struct rte_port_out_ops rte_port_ethdev_writer_nodrop_ops = {
+       .f_create = rte_port_ethdev_writer_nodrop_create,
+       .f_free = rte_port_ethdev_writer_nodrop_free,
+       .f_tx = rte_port_ethdev_writer_nodrop_tx,
+       .f_tx_bulk = rte_port_ethdev_writer_nodrop_tx_bulk,
+       .f_flush = rte_port_ethdev_writer_nodrop_flush,
+};

diff --git a/lib/librte_port/rte_port_ethdev.h b/lib/librte_port/rte_port_ethdev.h
index af67a12..201a79e 100644 (file)
--- a/lib/librte_port/rte_port_ethdev.h
+++ b/lib/librte_port/rte_port_ethdev.h
@@ -79,6 +79,25 @@ struct rte_port_ethdev_writer_params {
 /** ethdev_writer port operations */
 extern struct rte_port_out_ops rte_port_ethdev_writer_ops;
 
+/** ethdev_writer_nodrop port parameters */
+struct rte_port_ethdev_writer_nodrop_params {
+       /** NIC RX port ID */
+       uint8_t port_id;
+
+       /** NIC RX queue ID */
+       uint16_t queue_id;
+
+       /** Recommended burst size to NIC TX queue. The actual burst size can be
+       bigger or smaller than this value. */
+       uint32_t tx_burst_sz;
+
+       /** Maximum number of retries, 0 for no limit */
+       uint32_t n_retries;
+};
+
+/** ethdev_writer_nodrop port operations */
+extern struct rte_port_out_ops rte_port_ethdev_writer_nodrop_ops;
+
 #ifdef __cplusplus
 }
 #endif