[dpdk-dev] [PATCH v3] ether: use a default for max Rx frame size in configure()

[Andriy Berestovskyy]

At the moment rte_eth_dev_configure() behaves inconsistent:
 - for normal frames: zero max_rx_pkt_len uses a default
 - for jumbo frames: zero max_rx_pkt_len gives an error

This patch fixes this inconsistency by using a default value
if max_rx_pkt_len is zero both for normal and jumbo frames.

Signed-off-by: Andriy Berestovskyy <Andriy.Berestovskyy at caviumnetworks.com>
---

Notes:
    v3 changes:
     - use a default only if max_rx_pkt_len is zero
    
    v2 changes:
     - reword the commit title according to the check-git-log.sh

 lib/librte_ether/rte_ethdev.c | 23 ++++++++++++-----------
 lib/librte_ether/rte_ethdev.h |  2 +-
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index 4e1e6dc..2700c69 100644
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -790,6 +790,7 @@ rte_eth_dev_configure(uint8_t port_id, uint16_t nb_rx_q, uint16_t nb_tx_q,
 {
 	struct rte_eth_dev *dev;
 	struct rte_eth_dev_info dev_info;
+	uint32_t max_len;
 	int diag;
 
 	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL);
@@ -858,17 +859,23 @@ rte_eth_dev_configure(uint8_t port_id, uint16_t nb_rx_q, uint16_t nb_tx_q,
 	}
 
 	/*
-	 * If jumbo frames are enabled, check that the maximum RX packet
-	 * length is supported by the configured device.
+	 * Check that the maximum RX packet length is supported
+	 * by the configured device.
 	 */
 	if (dev_conf->rxmode.jumbo_frame == 1) {
-		if (dev_conf->rxmode.max_rx_pkt_len >
-		    dev_info.max_rx_pktlen) {
+		max_len = dev_info.max_rx_pktlen;
+	} else {
+		max_len = ETHER_MAX_LEN;
+	}
+	if (dev_conf->rxmode.max_rx_pkt_len == 0) {
+		dev->data->dev_conf.rxmode.max_rx_pkt_len = max_len;
+	} else {
+		if (dev_conf->rxmode.max_rx_pkt_len > max_len) {
 			RTE_PMD_DEBUG_TRACE("ethdev port_id=%d max_rx_pkt_len %u"
 				" > max valid value %u\n",
 				port_id,
 				(unsigned)dev_conf->rxmode.max_rx_pkt_len,
-				(unsigned)dev_info.max_rx_pktlen);
+				(unsigned int)max_len);
 			return -EINVAL;
 		} else if (dev_conf->rxmode.max_rx_pkt_len < ETHER_MIN_LEN) {
 			RTE_PMD_DEBUG_TRACE("ethdev port_id=%d max_rx_pkt_len %u"
@@ -878,12 +885,6 @@ rte_eth_dev_configure(uint8_t port_id, uint16_t nb_rx_q, uint16_t nb_tx_q,
 				(unsigned)ETHER_MIN_LEN);
 			return -EINVAL;
 		}
-	} else {
-		if (dev_conf->rxmode.max_rx_pkt_len < ETHER_MIN_LEN ||
-			dev_conf->rxmode.max_rx_pkt_len > ETHER_MAX_LEN)
-			/* Use default value */
-			dev->data->dev_conf.rxmode.max_rx_pkt_len =
-							ETHER_MAX_LEN;
 	}
 
 	/*
diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index d072538..ea760dc 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -349,7 +349,7 @@ enum rte_eth_tx_mq_mode {
 struct rte_eth_rxmode {
 	/** The multi-queue packet distribution mode to be used, e.g. RSS. */
 	enum rte_eth_rx_mq_mode mq_mode;
-	uint32_t max_rx_pkt_len;  /**< Only used if jumbo_frame enabled. */
+	uint32_t max_rx_pkt_len;  /**< If zero, use a default packet length. */
 	uint16_t split_hdr_size;  /**< hdr buf size (header_split enabled).*/
 	__extension__
 	uint16_t header_split : 1, /**< Header Split enable. */
-- 
2.7.4