raw_atomic6...turn_acquire(9)

📦 version 7.3.1, in nixpkgs unstable

💅 NAME 💅

okay so bestie, welcome to the Kernel API Manual, section 9 — this one's called raw_atomic64_dec_return_acquire, and it's the atomic decrement with acquire ordering. that's the whole vibe. one job, does it atomically, returns the new number. 🎀

✨ SYNOPSIS ✨

s64 raw_atomic64_dec_return_acquire (atomic64_t *v );

copy it exactly like that, spaces and all, because we do not freestyle function signatures in this house 🫶

🧚 ARGUMENTS 🧚

  • v — pointer to atomic64_t. that's it, that's the whole argument. just a pointer to the thing you're about to decrement. keep it safe, keep it aligned, keep it cute 💖

🔥 DESCRIPTION 🔥

so what does it actually do? it atomically updates v to (v - 1) with acquire ordering. atomically means no other thread can catch it mid-decrement and see some cursed in-between value — it's giving main character energy, nobody sees the messy part ✨

the acquire ordering part is doing real work, so don't tune it out: the ordering is part of the contract, not decoration.

it is safe to use in noinstr code. but like — if you're not in noinstr code, prefer atomic64_dec_return_acquire instead. the raw_ version is the special-occasion one, not your everyday fit 👑

🌈 RETURN 🌈

the updated value of v. as in, the value after the decrement, not the old one. so s64. no surprises, no drama 💜

🌸 SEE ALSO 🌸

the kernel file that actually lives here: ./include/linux/atomic/atomic-arch-fallback.h — that's the address, go say hi 🦋

and now. bestie. brace yourself. the friend group is massive:

like I said. huge friend group. iykyk 😭💀

and that's the page!! mwah 💋 this lil doc came from ./include/linux/atomic and it's stamped October 2026 — so yeah, future-dated and thriving. go decrement something atomically, bestie, and do it with acquire ordering ⭐💖

📦 where this page comes from