tb_consumed...ie_bandwidth(9)

🦋 tb_consumed...ie_bandwidth(9) 🦋

okay so bestie, you found it — a page straight outta the Kernel API Manual (that's the vibe, that's the whole manual, and yes we're doing this 💖). This one's about tb_consumed_usb3_pcie_bandwidth, which ngl has a name longer than my attention span but it's actually iconic once you get it. Sit down, hydrate, let's go 🫶

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✨ NAME ✨

tb_consumed_usb3_pcie_bandwidth — it's the function that tells you how much USB3/PCIe bandwidth is being consumed over a single link. that's the whole assignment. 💅

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🌈 SYNOPSIS 🌈

int tb_consumed_usb3_pcie_bandwidth (struct tb *tb , struct tb_port
*src_port , struct tb_port *dst_port , struct tb_port *port , int
*consumed_up , int *consumed_down );

literally copy that exactly, don't be cute with it 😭

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🎀 ARGUMENTS 🎀

so these are the little guys you're feeding in, one by one:

• tb — the domain structure. the big picture, the main character energy of the whole thing 👑
• src_port — the source protocol adapter. where the journey starts ✨
• dst_port — the destination protocol adapter. where it's headed 🦋
• port — the USB4 port where the consumed bandwidth gets calculated. this is the spot we're doing math on 📍
• consumed_up — the consumed upstream bandwidth, measured in Mb/s ⬆️
• consumed_down — the consumed downstream bandwidth, also in Mb/s ⬇️

note the units, bestie: Mb/s both times. not MB/s, not vibes/s. 💀

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💜 DESCRIPTION 💜

okay so what this actually does: it calculates the consumed USB3 and PCIe bandwidth at port, between the path going from src_port to dst_port. cute, tidy, does one thing 🧚

but here's the lowkey important bit — it does not take a USB3 tunnel that starts at src_port and ends on src_port into account. why? because that bandwidth is already included as part of the "first hop" USB3 tunnel. so it's not being shady or forgetting, it's literally already counted. iykyk 🌸

fr fr, don't go counting it twice. that's the trap. 🙈

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⭐ RETURN ⭐

• 0 on success — slay, we ate 🔥
• a negative errno otherwise — not slay, but honest 😭

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👑 SEE ALSO 👑

go off and read these next, bestie, they're all in the same friend group:

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

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and that's the page!! 🎀 all of it lives over in ./drivers/thunderbolt, and this edition is stamped October 2026 — so like, mark your calendar or whatever 💖 bye bestie, go calculate some bandwidth responsibly 🦋💅