bpf_cpumask_populate(9)

📦 version 7.3.1, in nixpkgs unstable

💅 bpf_cpumask_populate(9) — the kernel API manual page, bestie edition

okay so this is a page from the Kernel API Manual, section 9, and it's all about bpf_cpumask_populate(9). yes that's a mouthful, we're getting through it together 🫶

✨ NAME ✨

bpf_cpumask_populate — literally populates the CPU mask from the contents of a BPF memory region. that's the whole gig. no cap 🎀

🌸 SYNOPSIS 🌸

__bpf_kfunc int bpf_cpumask_populate (struct bpf_cpumask *cpumask , void *src , size_t src__sz );

🦋 ARGUMENTS 🦋

  • cpumask — the cpumask that's getting populated. it's the main character here, the one receiving the vibes 👑
  • src — the BPF memory holding the bit pattern. this is where the good stuff comes from ✨
  • src__sz — length of the BPF memory region, in bytes. gotta know how much you're working with, obviously 📏

💖 RETURN 💖

like, what do you get back? a few possibilities, bestie:

  • 0 — the struct bpf_cpumask * instance was populated successfully. slay, it worked 🎉
  • -EACCES — the memory region is too small to populate the cpumask. not enough to work with, tragic 😭
  • -EINVAL — the memory region is not aligned to the size of a long and the architecture does not support efficient unaligned accesses. so like... wrong alignment and your arch can't just shrug it off. rude 💀
ngl, if you're hitting -EINVAL it's giving alignment issues — check both things before you go blaming the kernel, ok? 🙈

🔥 SEE ALSO 🔥

the whole friend group, fr fr:

okay that's the whole thing, you ate that 💅✨ this came out of ./kernel/bpf and it's dated October 2026 — so like, future vibes only 🌈⭐ bye bestie, go populate some masks 🎀

📦 where this page comes from