atomic64_add(9)

📦 version 7.3.1, in nixpkgs unstable

💫 NAME 💫

okay so listen bestie — this is atomic64_add, straight out of the Kernel API Manual (atomic64_add(9)), and it does exactly one thing but it does it flawlessly: atomic add with relaxed ordering. no drama, no surprises, just vibes and math. periodt. 💅

✨ SYNOPSIS ✨

void atomic64_add (s64 i , atomic64_t *v );

🎀 ARGUMENTS 🎀

  • i — the s64 value you're adding. that's it, that's the number, it's giving "just a guy" energy and honestly? iconic. 💖
  • v — pointer to atomic64_t. this is the main character — the thing actually getting updated. 🫶

🦋 DESCRIPTION 🦋

so what happens is: v gets updated to (v + i), and the whole thing happens atomically, with relaxed ordering. no half-finished states, no other thread catching it mid-edit. it ate. 🔥

v  →  (v + i)

like yes it's just addition, but it's addition with ✨commitment✨.

⚠️ ngl this is important: it is unsafe to use in noinstr code — use raw_atomic64_add there instead. not me warning you twice, but like, i am. raw_atomic64_add. in noinstr code. don't forget. 😭

⭐ RETURN ⭐

Nothing. it's a void function, so there's no return value to catch, no little gift waiting for you at the end. you call it, it does the thing, you move on. lowkey refreshing tbh. 🦋

🌈 SEE ALSO 🌈

📍 source file on the map: Kernel file ./include/linux/atomic/atomic-instrumented.h

bestie there are so many siblings. like an unreasonable amount. i'm putting them in little family groups so your eyes don't glaze over, but every single one is here, no cap. 🧚

🌸 the atomic_* squad

💜 the atomic64_* squad (our people 💖)

🦋 the atomic_long_* squad

mwah 💖 that's the whole page, bestie. brought to you by ./include/linux/atomic, dated October 2026. go forth and add atomically. 🎀✨🦋

📦 where this page comes from