dup_or_alloc_cpuset(9)

📦 version 7.3.1, in nixpkgs unstable

💅 dup_or_alloc_cpuset(9) — the dup_or_alloc_cpuset page, bestie 🎀

okay so this is a page from the Kernel API Manual and honestly it's giving "short but mighty" ✨ — the whole thing is one function that does one little job and does it flawlessly. let's get into it 🫶

✨ NAME ✨

dup_or_alloc_cpuset — duplicate or allocate a new cpuset 💖

like, the name literally tells you the whole plot. either you're copying a cpuset or you're making a fresh one. that's it. that's the function. periodt 👑

🌸 SYNOPSIS 🌸

struct cpuset * dup_or_alloc_cpuset (struct cpuset *cs );

so it takes one pointer to a struct cpuset, hands you back a pointer to a struct cpuset, and that's the whole signature. no cap, it's that simple. lowkey iconic for how unbothered it is 💅

🦋 ARGUMENTS 🦋

  • cs — the source cpuset you wanna duplicate, bestie. and if you pass NULL? then it skips the whole copying thing entirely and just does a fresh allocation for you instead 🎀

💜 DESCRIPTION 💜

so what actually happens inside? great question, glad you asked 💖

This creates a new cpuset by either:

  1. Duplicating an existing cpuset — this is the path you take when cs is non-NULL ✨ you already got a cpuset and you want a copy of it, slay.
  2. Allocating a fresh cpuset with zero-initialized masks — this is the NULL route 🧚 you hand it nothing and it hands you back a brand new cpuset whose masks are all zeroed out. clean slate energy, main character energy, we love to see it 🌈
two branches, one function. choose your fighter 💀

⭐ RETURN ⭐

  • On success? you get a pointer to the newly allocated cpuset 👑 ate and left no crumbs
  • On failure? you get NULL 😭 and ngl you should probably check for that before you go dereferencing it, just saying 🙈

🍓 SEE ALSO 🍓

okay this is the part where the page just goes off — the related-reference list is genuinely enormous and honestly? we're obsessed. all of these live in the kernel file ./kernel/cgroup/cpuset.c 🎀

iykyk — cpuset girlies stay booked and busy 💅✨

and that's the page!! 💖 brought to you from ./kernel/cgroup, dated October 2026 🌸 bestie go forth and duplicate responsibly 🫶🎀

📦 where this page comes from