tb_consumed_dp_bandwidth(9)

💅 tb_consumed_dp_bandwidth(9) 💅

okay so this is a page from the Kernel API Manual and it's all about tb_consumed_dp_bandwidth — the function that tells you how much DisplayPort bandwidth a single link is already eating up. bestie, let's get into it 🎀

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✨ NAME ✨

tb_consumed_dp_bandwidth — consumed DP bandwidth over a single link 💖

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🌸 SYNOPSIS 🌸

int tb_consumed_dp_bandwidth (struct tb *tb , struct tb_port *src_port ,
struct tb_port *dst_port , struct tb_port *port , int *consumed_up , int
*consumed_down );

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🦋 ARGUMENTS 🦋

• tb — the domain structure, like, the whole vibe container for this Thunderbolt domain 👑
• src_port — source protocol adapter, where the traffic starts its little journey
• dst_port — destination protocol adapter, where it's headed 🫶
• port — the USB4 port that the consumed bandwidth is calculated for, this is the main character of the calculation ✨
• consumed_up — consumed upstream bandwidth, in Mb/s ⬆️
• consumed_down — consumed downstream bandwidth, in Mb/s ⬇️

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💜 DESCRIPTION 💜

So what it actually does: it calculates the consumed DP bandwidth at port between the path from src_port to dst_port. literally the math of "how much of this link is already spoken for" 🔥

🚨 important caveat, do not skip: it does not take tunnel starting from src_port and ending from src_port into account. yeah, src to src — that's what the original says, iykyk, no cap 🙈

and if there's bandwidth reserved for any of the groups between src_port and dst_port (but not yet used 👀) then that reserved-but-unused bandwidth is also taken into account in the returned consumed bandwidth. so it's not just what's flowing right now, it's what's been claimed. ate 💅

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⭐ RETURN ⭐

0 on success 🎉 — negative errno otherwise 😭

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🌈 SEE ALSO 🌈

• Kernel file ./drivers/thunderbolt/tb.c struct tb_cm(9) 🍓
• tb_consumed_usb3_pcie_bandwidth(9)
• tb_maximum_bandwidth(9)
• tb_available_bandwidth(9)
• tb_configure_asym(9)
• tb_configure_sym(9)

go read those next, bestie, they're all in the same friend group 🧚

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💀 tiny reminder: this whole thing lives in ./drivers/thunderbolt, dated October 2026. slay, thanks for coming to my TED talk, ily, bye 💖🌸✨