-----Original Message-----
From: Thomas Monjalon <redacted>
Sent: Monday, September 27, 2021 2:19 PM
To: Wang, Jie1X <redacted>
Cc: dev@dpdk.org; Yigit, Ferruh <redacted>;
andrew.rybchenko@oktetlabs.ru; Li, Xiaoyun [off-list ref]; Yang,
SteveX [off-list ref]
Subject: Re: [PATCH v9 1/3] ethdev: add an API to get device configuration info

26/09/2021 11:20, Jie Wang:

quoted

This patch adds a new API "rte_eth_dev_conf_info_get()" to help users
get device configuration info.

Cc: stable@dpdk.org

No we don't backport new features.

Ok, I'll remove 'Cc: stable@dpdk.org'.

quoted

Signed-off-by: Jie Wang <redacted>

[...]

quoted

+ * Retrieve the configuration of an Ethernet device.
+ *
+ * @param port_id
+ *   The port identifier of the Ethernet device.
+ * @param dev_conf_info
+ *   A pointer to a structure of type *rte_eth_conf* to be filled with
+ *   the configuration of the Ethernet device.
+ *   And the memory of the structure should be allocated by the caller.
+ * @return
+ *   - (0) if successful.
+ *   - (-ENODEV) if *port_id* invalid.
+ *   - (-EINVAL) if bad parameter.
+ */
+__rte_experimental
+int rte_eth_dev_conf_info_get(uint16_t port_id,
+				struct rte_eth_conf *dev_conf_info);

It does not make sense to me.
rte_eth_conf is passed by the app to rte_eth_dev_configure.
Why the app would need to get the same info back?

In rte_eth_dev_configure, dev->data->dev_conf copies the info from port->dev_conf, and then the driver updates it. It doesn't same as port->dev_conf.
We need to get the updated device configuration.