atomic_long_...h_add_unless(9)

📦 version 7.3.1, in nixpkgs unstable

💅 atomic_long_...h_add_unless(9) — kernel API manual 🎀

okay bestie, so this one lives in the Kernel API Manual, and the page is literally called atomic_long_fetch_add_unless(9) — yes the header got truncated and it's giving "my name is a mystery" energy, but we know her 💖

✨ NAME ✨

atomic_long_fetch_add_unless — atomic add unless value, with full ordering 🦋

🌸 SYNOPSIS 🌸

long atomic_long_fetch_add_unless (atomic_long_t *v , long a , long u );

🎀 ARGUMENTS 🎀

  • v — pointer to atomic_long_t 👑 (the thing we're being all atomic about)
  • a — long value to add ➕
  • u — long value to compare with 🆚

💜 DESCRIPTION 💜

so here's the vibe check: if (v != u), she atomically updates v to (v + a) with full ordering ✨. Literally does the math and the memory ordering in one go, no cap.

Otherwise — meaning v already equals u — v is not modified, and relaxed ordering is provided 🫶. She looked at it, said "not today", and gave you the chill version of the ordering instead 💅

⚠️ unsafe to use in noinstr code — bestie please, use raw_atomic_long_fetch_add_unless there instead 😭 fr fr, this is the one caveat and it's not a drill 💀

⭐ RETURN ⭐

The original value of v — like, the value from before the add. time-travel queen behavior 🕰️👑

🌈 SEE ALSO 🌈

Kernel file ./include/linux/atomic/atomic-instrumented.h — and the whole extended family is here, gathered for the group chat 📱✨

the atomic_* girlies:

the atomic64_* crew (sixty-four of them, highkey iconic):

the atomic_long_* main characters (yes, our girl's whole family 💅):

💀 okay that's everybody, go read them, iykyk 🫶

✨ that's the whole page bestie ✨ this cutie came from ./include/linux/atomic, dated October 2026, and yeah the footer says atomic_long_...h_add_unless(9) again because the header and footer are matching, and honestly? coordinated. slay 💅🎀🦋

📦 where this page comes from