raw_atomic_long_add_unless(9)

📦 version 7.3.1, in nixpkgs unstable

💅 raw_atomic_long_add_unless

okay so bestie, welcome to the Kernel API Manual ✨ — this is the page for raw_atomic_long_add_unless, and it's literally the "add, but only if you're not matching this one value" girlie. full ordering included, no cap.

🌸 NAME 🌸

raw_atomic_long_add_unless — atomic add unless value with full ordering 🎀

✨ SYNOPSIS ✨

bool raw_atomic_long_add_unless (atomic_long_t *v , long a , long u );

🧚 ARGUMENTS 🧚

  • v — pointer to atomic_long_t. she's the main character, the thing getting updated 💖
  • a — a long value to add. this is the amount going in, bestie
  • u — a long value to compare with. the vibe check value, if you will 🦋

🔥 DESCRIPTION 🔥

So here's the tea 🍵 — if (v != u), then it atomically updates v to (v + a) with full ordering. iconic behavior, truly.

Otherwise — like, if v does equal u* — then v` is not modified and you get relaxed ordering instead. she simply didn't feel like it that day 💀

Safe to use in noinstr code 🫶 but prefer atomic_long_add_unless everywhere else, okay? iykyk.

ngl the "safe in noinstr" thing is real and the "prefer atomic_long_add_unless elsewhere" thing is also real — don't come for me, that's just what the page says 🙈

👑 RETURN 👑

true if v was updated, false otherwise. that's it, that's the whole mood ⭐

🌈 SEE ALSO 🌈

Kernel file ./include/linux/atomic/atomic-long.h — go read it, she's thorough 💜

and now, the whole friend group 😭 look at all these siblings:

and that's the whole page bestie, you ate that 💅✨

source file: ./include/linux/atomic · dated October 2026 · Kernel API Manual — mwah, go forth and be atomic 🫶🎀💖

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