[dpdk-dev] [PATCH 3/4] examples/vhost: remove dequeue zero-copy support

[Maxime Coquelin <maxime.coquelin@redhat.com>]

Dequeue zero-copy feature is being removed from the
Vhost library. This preliminary patch removes its uses
in the Vhost example application.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 examples/vhost/main.c | 18 +-----------------
 1 file changed, 1 insertion(+), 17 deletions(-)

diff --git a/examples/vhost/main.c b/examples/vhost/main.c
index e1578e7956..959c0c2838 100644
--- a/examples/vhost/main.c
+++ b/examples/vhost/main.c
@@ -92,7 +92,6 @@ static uint32_t enable_tx_csum;
 static uint32_t enable_tso;
 
 static int client_mode;
-static int dequeue_zero_copy;
 
 static int builtin_net_driver;
 
@@ -247,16 +246,6 @@ port_init(uint16_t port)
 	rx_ring_size = RTE_TEST_RX_DESC_DEFAULT;
 	tx_ring_size = RTE_TEST_TX_DESC_DEFAULT;
 
-	/*
-	 * When dequeue zero copy is enabled, guest Tx used vring will be
-	 * updated only when corresponding mbuf is freed. Thus, the nb_tx_desc
-	 * (tx_ring_size here) must be small enough so that the driver will
-	 * hit the free threshold easily and free mbufs timely. Otherwise,
-	 * guest Tx vring would be starved.
-	 */
-	if (dequeue_zero_copy)
-		tx_ring_size = 64;
-
 	tx_rings = (uint16_t)rte_lcore_count();
 
 	/* Get port configuration. */
@@ -457,8 +446,7 @@ us_vhost_usage(const char *prgname)
 	"		--socket-file: The path of the socket file.\n"
 	"		--tx-csum [0|1] disable/enable TX checksum offload.\n"
 	"		--tso [0|1] disable/enable TCP segment offload.\n"
-	"		--client register a vhost-user socket as client mode.\n"
-	"		--dequeue-zero-copy enables dequeue zero copy\n",
+	"		--client register a vhost-user socket as client mode.\n",
 	       prgname);
 }
 
@@ -483,7 +471,6 @@ us_vhost_parse_args(int argc, char **argv)
 		{"tx-csum", required_argument, NULL, 0},
 		{"tso", required_argument, NULL, 0},
 		{"client", no_argument, &client_mode, 1},
-		{"dequeue-zero-copy", no_argument, &dequeue_zero_copy, 1},
 		{"builtin-net-driver", no_argument, &builtin_net_driver, 1},
 		{NULL, 0, 0, 0},
 	};
@@ -1510,9 +1497,6 @@ main(int argc, char *argv[])
 	if (client_mode)
 		flags |= RTE_VHOST_USER_CLIENT;
 
-	if (dequeue_zero_copy)
-		flags |= RTE_VHOST_USER_DEQUEUE_ZERO_COPY;
-
 	/* Register vhost user driver to handle vhost messages. */
 	for (i = 0; i < nb_sockets; i++) {
 		char *file = socket_files + i * PATH_MAX;
-- 
2.26.2