rdmacg_unregister_device(9)

💅 rdmacg_unregister_device (kernel API manual, bestie)

okay so real talk, this one's from the Kernel API Manual and it's about saying bye-bye to an rdma controller device. yes, the whole page is one (1) function. she's short, she's sweet, she's important. let's go 🎀

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✨ NAME ✨

rdmacg_unregister_device — unregister an rdmacg device from the rdma controller. that's it. that's the whole job. she clocks out and takes the device with her 💅

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🌸 SYNOPSIS 🌸

void rdmacg_unregister_device (struct rdmacg_device *device );

literally returns nothing (void), and honestly? iconic. no return value to check, no error to handle, she just does the thing 🫶

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🦋 ARGUMENTS 🦋

• device — pointer to the rdmacg device. and not just any random device, bestie, this has to be one that was previously registered with the rdma controller using rdmacg_register_device. like, you can't unregister something that was never registered. that's not how any of this works 🙈

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👑 DESCRIPTION 👑

okay this is the part where you Actually Read It, because it's giving "one sentence, entire vibe check" 🔥

The IB stack must invoke this after all the resources of the IB device are destroyed and after ensuring that no more resources will be created when this API is invoked.

read that again. both conditions. no cap.

⚠️ so like — resources destroyed first, and you gotta be sure nothing new is gonna get created when you call this. not before. not during. this is not a "yeah probably fine" situation, it's a "you must guarantee it" situation 💀

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💖 SEE ALSO 💖

• Kernel file ./kernel/cgroup/rdma.c
• uncharge_cg_locked(9)
• rdmacg_event_locked(9)
• rdmacg_uncharge_hierarchy(9)
• rdmacg_uncharge(9)
• rdmacg_try_charge(9)
• rdmacg_register_device(9)
• rdmacg_css_offline(9)

go read the whole friend group, they all make sense together 🌈

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aaand that's a wrap, bestie 🎀 this page lives at ./kernel/cgroup, dated October 2026, and she's part of that Kernel API Manual life. mwah, study safe, and don't call unregister before you destroy your resources 💜✨