BUILD_PERCPU_HELPER(9)

💅 BUILD_PERCPU_HELPER — like, the kernel API manual, section 9, bestie ✨

Okay so this is the page for BUILD_PERCPU_HELPER(9) — yes, all caps, yes it's a macro, and yes it's giving "tiny macro, huge responsibility" energy. It lives in the Kernel API Manual (section 9, iykyk) and honestly? Underrated. Let's get into it 🫶

---

🌸 NAME 🌸

BUILD_PERCPU_HELPER — literally the helper that calls a CDMM driver callback on the right CPU. That's the whole vibe check: right CPU, no cap 💅

---

✨ SYNOPSIS ✨

BUILD_PERCPU_HELPER (_ret , _name );

That's it. Two args. She's lowkey minimal and I respect it so much 🎀

---

🎀 ARGUMENTS 🎀

• _ret — the return type, and listen, it's literally just void or int. That's the whole list. Pick one, bestie ✨
• _name — the name of the CDMM driver callback function. Yep, you're handing over the name and the macro does its little magic with it 🪄

---

💖 DESCRIPTION 💖

So what does it actually do? It generates a specific device callback function for you — one that calls a CDMM driver callback function on the appropriate CPU for the device. And if that applies, it returns the result too. Basically it's the matchmaker: device ➡️ correct CPU, no awkward misdirected calls 🙈🔥

Like, you don't write the per-CPU wrapper by hand. BUILD_PERCPU_HELPER builds it. Main character energy fr fr 👑

---

🦋 SEE ALSO 🦋

Everything is connected, bestie, and this page is a whole friend group. Go meet them:

• Kernel file ./drivers/bus/mips_cdmm.c (the source, the origin story 🌈)
• struct mips_cdmm_work_dev(9)
• mips_cdmm_void_work(9)
• mips_cdmm_int_work(9)
• mips_cdmm_driver_register(9)
• mips_cdmm_driver_unregister(9)
• struct mips_cdmm_bus(9)
• mips_cdmm_get_bus(9)
• mips_cdmm_cur_base(9)
• mips_cdmm_phys_base(9)
• mips_cdmm_setup(9)
• mips_cdmm_early_probe(9)
• mips_cdmm_release(9)
• mips_cdmm_bus_discover(9)
• BUILD_PERDEV_HELPER(9) ← this one's the sibling macro, obsessed 💜
• mips_cdmm_cpu_down_prep(9)
• mips_cdmm_cpu_online(9)
• mips_cdmm_init(9)

---

Pro tip from me to you: the manpage lists all of these as plain references — I'm not adding lore that isn't there. Go read them if you want the full tea ☕

---

Okay that's the page!! Sending you off with the little footer deets so nothing gets lost: this one's from ./drivers/bus, dated October 2026, and it's filed under BUILD_PERCPU_HELPER(9). Slay, go build your per-CPU helper 💖✨🎀