tb_configure_asym(9)

💅 tb_configure_asym(9) — the kernel API glow-up page 🦋

okay so this is a page from the Kernel API Manual, function tb_configure_asym(9), and honestly it's giving "networking but make it fashion." let's get into it bestie 🎀

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✨ NAME ✨

tb_configure_asym — transition links to asymmetric if needed 👑

like, it checks whether your link should be lopsided (in the lane sense) and if so, it makes it happen. no cap.

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🌸 SYNOPSIS 🌸

int tb_configure_asym (struct tb *tb , struct tb_port *src_port , struct
tb_port *dst_port , int requested_up , int requested_down );

yup, that's the whole signature, copied exactly, don't come for me 💅

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💖 ARGUMENTS 💖

• tb — the domain structure. it's the whole vibe container, the domain, the main character 🌈
• src_port — source adapter to start the transition from. where the glow-up begins ✨
• dst_port — destination adapter. the other end of the link, the destination of the slay 🫶
• requested_up — additional bandwidth (Mb/s) required upstream. yes, in Mb/s, keep up 🔥
• requested_down — additional bandwidth (Mb/s) required downstream. also Mb/s, also extra, also important 💜

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🦋 DESCRIPTION 🦋

okay so here's what it actually does: it transitions the links between src_port and dst_port into asymmetric mode — that's three lanes in the direction going from src_port towards dst_port, and one lane in the opposite direction 🌸

but like, only if the bandwidth requirements on that link exceed asym_threshold. and "bandwidth requirements" means requested plus what's currently consumed, so don't forget the currently-consumed part bestie, it's literally part of the math 😭

⚠️ important: must be called with available >= requested over all links. all of them. every single one. don't @ me, that's just the rule 💀

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⭐ RETURN ⭐

• 0 on success — slay 💅
• negative errno otherwise — not slay, check your errno 🙈

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🎀 SEE ALSO 🎀

• Kernel file ./drivers/thunderbolt/tb.c — struct tb_cm(9)
• tb_consumed_usb3_pcie_bandwidth(9)
• tb_consumed_dp_bandwidth(9)
• tb_maximum_bandwidth(9)
• tb_available_bandwidth(9)
• tb_configure_sym(9) — the symmetric sibling, the balanced one, iykyk 🌈

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and that's the page! 🧚 this one lives in ./drivers/thunderbolt, dated October 2026, and yeah, it's tb_configure_asym(9) all the way down. go configure some asymmetry, bestie, you've got this 💖✨