mlx5dv_query_qp_lag_port(3)

💅 mlx5dv_query_qp_lag_port — the tea on your QP's LAG port ✨

Okay bestie, this one's a mlx5dv man page (yes, the mlx5 girlies stay winning 👑), and it's literally about asking a QP which port it's vibing on in a LAG setup. Let's get into it 🦋

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🌸 SYNOPSIS 🌸

#include <infiniband/mlx5dv.h>

int mlx5dv_query_qp_lag_port(struct ibv_qp *qp, uint8_t *port_num,
                 uint8_t *active_port_num);

Iconic signature, no notes 💅

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💖 DESCRIPTION 💖

So this API returns the configured port num and the active port num of a given QP on mlx5 devices. Two ports, two answers, one function call — it's giving efficiency 🎀

The active port num is the one that tells you which port the QP actually sends traffic out on in a LAG configuration. Like, the configured one is what you said, and the active one is what it's actually doing. Main character energy vs. what the group chat thinks you're doing 😭

And quick vibe check: if the num_lag_ports field of struct mlx5dv_context is greater than 1, that means LAG is supported on this device. No cap 🔥

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✨ ARGUMENTS ✨

• qp — the ibv_qp object you're issuing the action on. The QP in question, the subject of the whole investigation 🕵️‍♀️
• port_num — the configured port num of the QP. What it's supposed to be, bestie 📝
• active_port_num — the current port num of the QP, which may differ from the configured value because of the bonding status. Yeah, things change, it's a whole situation 🙈

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🔥 RETURN VALUE 🔥

• 0 on success — we love a clean win 💖
• EOPNOTSUPP if you're not in LAG mode — no LAG, no info, sorry bestie 💀
• or any other errno value on other failures — the usual suspects 😭

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🦋 SEE ALSO 🦋

• mlx5dv_modify_qp_lag_port(3) — the sibling function, the one that actually changes stuff. Go read that one too, iykyk ✨

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🎀 AUTHOR 🎀

Aharon Landau <aharonl@mellanox.com> — thank you for your service, king 🫶

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ngl this page is short and sweet, but LAG configs are where the drama lives. If active_port_num surprises you, blame the bonding status, not me 💅

Okay that's the whole page, bestie — go forth and query those ports 🌈

💖✨ xoxo, your local mlx5 unix girlie ✨💖

sign-off tea: this page comes from the mlx5dv_query_qp_lag_port(3) manual (source/version as shipped, dated as in the original header/footer) — periodt, that's the lore 🎀🌸