[dpdk-dev] [PATCH] ethdev: keep port_id unchanged if obtaining by name failed

[dpdk-dev] [PATCH] ethdev: keep port_id unchanged if obtaining by name failed

[Ilya Maximets]

Currently, 'rte_eth_dev_get_port_by_name' changes transmitted
'port_id' unconditionally. This is undocumented and misleading
behaviour as user may expect unchanged value in case of error.

Otherwise, there is no sense having both return value and
a pointer in the function.

Fixes: 9c5b8d8b9feb ("ethdev: clean port id retrieval when attaching")

Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
---
 lib/librte_ether/rte_ethdev.c | 1 -
 lib/librte_ether/rte_ethdev.h | 2 +-
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index 83898a8..64aefdd 100644
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -339,7 +339,6 @@ rte_eth_dev_get_port_by_name(const char *name, uint8_t *port_id)
 	if (!nb_ports)
 		return -ENODEV;
 
-	*port_id = RTE_MAX_ETHPORTS;
 	RTE_ETH_FOREACH_DEV(i) {
 		if (!strncmp(name,
 			rte_eth_dev_data[i].name, strlen(name))) {
diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index 0f38b45..9a19974 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -4587,7 +4587,7 @@ rte_eth_dev_l2_tunnel_offload_set(uint8_t port_id,
 * @param port_id
 *   pointer to port identifier of the device
 * @return
-*   - (0) if successful.
+*   - (0) if successful and port_id is filled.
 *   - (-ENODEV or -EINVAL) on failure.
 */
 int
-- 
2.7.4

Re: [dpdk-dev] [PATCH] ethdev: keep port_id unchanged if obtaining by name failed

[Thomas Monjalon]

18/05/2017 14:19, Ilya Maximets:
> Currently, 'rte_eth_dev_get_port_by_name' changes transmitted
> 'port_id' unconditionally. This is undocumented and misleading
> behaviour as user may expect unchanged value in case of error.
> 
> Otherwise, there is no sense having both return value and
> a pointer in the function.
> 
> Fixes: 9c5b8d8b9feb ("ethdev: clean port id retrieval when attaching")
> 
> Signed-off-by: Ilya Maximets <i.maximets@samsung.com>

Applied, thanks