[PATCH v4 01/10] net/tap: replace runtime speed capability with constant

[Stephen Hemminger]

The TAP/TUN virtual device always operates at 10G. The link speed is
set in the static initializer for pmd_link, so the runtime assignments
in rte_pmd_tap_probe() and rte_pmd_tun_probe() are redundant.

Replace tap_dev_speed_capa(), which dynamically computed speed
capabilities against pmd_link.link_speed, with a compile-time
constant TAP_SPEED_CAPA. Remove the unused 'speed' variable and
redundant assignments.

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
---
 drivers/net/tap/rte_eth_tap.c | 48 ++++++-----------------------------
 1 file changed, 8 insertions(+), 40 deletions(-)

diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
index 7a8a98cddb..aa236cf967 100644
--- a/drivers/net/tap/rte_eth_tap.c
+++ b/drivers/net/tap/rte_eth_tap.c
@@ -891,39 +891,13 @@ tap_dev_configure(struct rte_eth_dev *dev)
 	return 0;
 }
 
-static uint32_t
-tap_dev_speed_capa(void)
-{
-	uint32_t speed = pmd_link.link_speed;
-	uint32_t capa = 0;
-
-	if (speed >= RTE_ETH_SPEED_NUM_10M)
-		capa |= RTE_ETH_LINK_SPEED_10M;
-	if (speed >= RTE_ETH_SPEED_NUM_100M)
-		capa |= RTE_ETH_LINK_SPEED_100M;
-	if (speed >= RTE_ETH_SPEED_NUM_1G)
-		capa |= RTE_ETH_LINK_SPEED_1G;
-	if (speed >= RTE_ETH_SPEED_NUM_5G)
-		capa |= RTE_ETH_LINK_SPEED_2_5G;
-	if (speed >= RTE_ETH_SPEED_NUM_5G)
-		capa |= RTE_ETH_LINK_SPEED_5G;
-	if (speed >= RTE_ETH_SPEED_NUM_10G)
-		capa |= RTE_ETH_LINK_SPEED_10G;
-	if (speed >= RTE_ETH_SPEED_NUM_20G)
-		capa |= RTE_ETH_LINK_SPEED_20G;
-	if (speed >= RTE_ETH_SPEED_NUM_25G)
-		capa |= RTE_ETH_LINK_SPEED_25G;
-	if (speed >= RTE_ETH_SPEED_NUM_40G)
-		capa |= RTE_ETH_LINK_SPEED_40G;
-	if (speed >= RTE_ETH_SPEED_NUM_50G)
-		capa |= RTE_ETH_LINK_SPEED_50G;
-	if (speed >= RTE_ETH_SPEED_NUM_56G)
-		capa |= RTE_ETH_LINK_SPEED_56G;
-	if (speed >= RTE_ETH_SPEED_NUM_100G)
-		capa |= RTE_ETH_LINK_SPEED_100G;
-
-	return capa;
-}
+/* Speed capabilities for virtual TAP/TUN device (always 10G) */
+#define TAP_SPEED_CAPA (RTE_ETH_LINK_SPEED_10M | \
+			RTE_ETH_LINK_SPEED_100M | \
+			RTE_ETH_LINK_SPEED_1G | \
+			RTE_ETH_LINK_SPEED_2_5G | \
+			RTE_ETH_LINK_SPEED_5G | \
+			RTE_ETH_LINK_SPEED_10G)
 
 static int
 tap_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
@@ -936,7 +910,7 @@ tap_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
 	dev_info->max_rx_queues = RTE_PMD_TAP_MAX_QUEUES;
 	dev_info->max_tx_queues = RTE_PMD_TAP_MAX_QUEUES;
 	dev_info->min_rx_bufsize = 0;
-	dev_info->speed_capa = tap_dev_speed_capa();
+	dev_info->speed_capa = TAP_SPEED_CAPA;
 	dev_info->rx_queue_offload_capa = TAP_RX_OFFLOAD;
 	dev_info->rx_offload_capa = dev_info->rx_queue_offload_capa;
 	dev_info->tx_queue_offload_capa = TAP_TX_OFFLOAD;
@@ -2325,7 +2299,6 @@ set_mac_type(const char *key __rte_unused,
  * Open a TUN interface device. TUN PMD
  * 1) sets tap_type as false
  * 2) intakes iface as argument.
- * 3) as interface is virtual set speed to 10G
  */
 static int
 rte_pmd_tun_probe(struct rte_vdev_device *dev)
@@ -2373,7 +2346,6 @@ rte_pmd_tun_probe(struct rte_vdev_device *dev)
 			}
 		}
 	}
-	pmd_link.link_speed = RTE_ETH_SPEED_NUM_10G;
 
 	TAP_LOG(DEBUG, "Initializing pmd_tun for %s", name);
 
@@ -2495,7 +2467,6 @@ rte_pmd_tap_probe(struct rte_vdev_device *dev)
 	const char *name, *params;
 	int ret;
 	struct rte_kvargs *kvlist = NULL;
-	int speed;
 	char tap_name[RTE_ETH_NAME_MAX_LEN];
 	char remote_iface[RTE_ETH_NAME_MAX_LEN];
 	struct rte_ether_addr user_mac = { .addr_bytes = {0} };
@@ -2545,8 +2516,6 @@ rte_pmd_tap_probe(struct rte_vdev_device *dev)
 		return 0;
 	}
 
-	speed = RTE_ETH_SPEED_NUM_10G;
-
 	/* use tap%d which causes kernel to choose next available */
 	strlcpy(tap_name, DEFAULT_TAP_NAME "%d", RTE_ETH_NAME_MAX_LEN);
 	memset(remote_iface, 0, RTE_ETH_NAME_MAX_LEN);
@@ -2587,7 +2556,6 @@ rte_pmd_tap_probe(struct rte_vdev_device *dev)
 				persist = 1;
 		}
 	}
-	pmd_link.link_speed = speed;
 
 	TAP_LOG(DEBUG, "Initializing pmd_tap for %s", name);
 
-- 
2.51.0