__scx_cid_to_cpu(9)

📦 version 7.3.1, in nixpkgs unstable

💅 __scx_cid_to_cpu — the kernel API manual, but make it make sense

okay bestie, welcome to the __scx_cid_to_cpu(9) page — this is the kernel API manual and honestly it's a tiny one, so we'll be in and out, no cap 🎀

✨ NAME ✨

__scx_cid_to_cpu — an unchecked cid→cpu table lookup 🦋

like, the table lookup with zero vibe checks attached. she trusts you. that's the whole bit.

✨ SYNOPSIS ✨

s32 __scx_cid_to_cpu (s32 cid );

one arg, one s32 back, and it's literally that simple 💅

✨ ARGUMENTS ✨

  • cid — the cid you're looking up 🍓. Must be in [0, num_possible_cpus) — that range is not a suggestion, it's the rule, and nobody on this page is gonna re-check it for you bestie 😭

✨ DESCRIPTION ✨

so here's the tea 🫖: this one is intended for callsites that have already validated cid and that run on a live scheduler, which is what *guarantees the tables are published and stable** ✨

read that again, because it's doing a lot of heavy lifting:

  • you already validated cid yourself → she's not redoing your homework 🙈
  • you're on a live scheduler → that's the guarantee that the tables are published and stable in the first place 🌸
⚠️ unchecked is right there in the name, queen. If you haven't validated cid or you're not on a live scheduler, this is not the function for you — the whole "tables are published and stable" deal is a promise you keep, not her. 💀

it's giving main-character-for-internal-callsites energy, and honestly? iconic 👑

✨ SEE ALSO ✨

all the siblings in ./kernel/sched/ext/cid.h — a whole little cid/cpu/cmasks friend group, fr fr 🧚:

iykyk 💜

and that's the whole page, bestie — slay, you're done 🌈

sign-off 🎀 — this little masterpiece lives under ./kernel/sched/ext, and the page itself is dated October 2026. no cap, that's the version info and the date, right there at the bottom where the footer would've been 🫶

📦 where this page comes from