atomic64_fetch_or_release(9)

💅 atomic64_fetch_or_release(9) — the Kernel API Manual, bestie edition 🎀

okay so this is a page from the Kernel API Manual, and the star of the show is atomic64_fetch_or_release — literally the friend who ORs your bits and holds the release gate. it's giving "I do two things and I do both flawlessly" energy ✨

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🌸 NAME 🌸

atomic64_fetch_or_release — atomic bitwise OR with release ordering 💖

like, atomically. no half-ORs. no races. we don't do that here.

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🦋 SYNOPSIS 🦋

s64 atomic64_fetch_or_release (s64 i , atomic64_t *v );

two arguments, one 64-bit-ish OR, zero chaos 💫

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🎀 ARGUMENTS 🎀

• i — an s64 value, aka the thing you're OR-ing in, the little contribution 💅
• v — pointer to atomic64_t, aka where the magic lands, the main character 🫶

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👑 DESCRIPTION 👑

so here's the tea: it atomically updates v to (v | i) with release ordering. atomically means nobody sees a half-finished update, and release ordering means the ordering guarantees are real and not vibes-based 🔥

⚠️ unsafe to use in noinstr code — if you're in noinstr, use raw_atomic64_fetch_or_release there instead. no cap, that's the whole plot twist 💀

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⭐ RETURN ⭐

it gives you back the original value of v — the before picture, the pre-OR era, the value as it was before you touched it 😭 iconic behaviour honestly

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🌈 SEE ALSO 🌈

kernel file ./include/linux/atomic/atomic-instrumented.h — and bestie, the whole atomic family lives here. every sibling, every cousin, every _acquire / _release / _relaxed variant you could ever want. go say hi 👋

atomic_read(9), atomic_read_acquire(9), atomic_set(9), atomic_set_release(9),
atomic_add(9), atomic_add_return(9), atomic_add_return_acquire(9),
atomic_add_return_release(9), atomic_add_return_relaxed(9),
atomic_fetch_add(9), atomic_fetch_add_acquire(9),
atomic_fetch_add_release(9), atomic_fetch_add_relaxed(9), atomic_sub(9),
atomic_sub_return(9), atomic_sub_return_acquire(9),
atomic_sub_return_release(9), atomic_sub_return_relaxed(9),
atomic_fetch_sub(9), atomic_fetch_sub_acquire(9),
atomic_fetch_sub_release(9), atomic_fetch_sub_relaxed(9), atomic_inc(9),
atomic_inc_return(9), atomic_inc_return_acquire(9),
atomic_inc_return_release(9), atomic_inc_return_relaxed(9),
atomic_fetch_inc(9), atomic_fetch_inc_acquire(9),
atomic_fetch_inc_release(9), atomic_fetch_inc_relaxed(9), atomic_dec(9),
atomic_dec_return(9), atomic_dec_return_acquire(9),
atomic_dec_return_release(9), atomic_dec_return_relaxed(9),
atomic_fetch_dec(9), atomic_fetch_dec_acquire(9),
atomic_fetch_dec_release(9), atomic_fetch_dec_relaxed(9), atomic_and(9),
atomic_fetch_and(9), atomic_fetch_and_acquire(9),
atomic_fetch_and_release(9), atomic_fetch_and_relaxed(9),
atomic_andnot(9), atomic_fetch_andnot(9),
atomic_fetch_andnot_acquire(9), atomic_fetch_andnot_release(9),
atomic_fetch_andnot_relaxed(9), atomic_or(9), atomic_fetch_or(9),
atomic_fetch_or_acquire(9), atomic_fetch_or_release(9),
atomic_fetch_or_relaxed(9), atomic_xor(9), atomic_fetch_xor(9),
atomic_fetch_xor_acquire(9), atomic_fetch_xor_release(9),
atomic_fetch_xor_relaxed(9), atomic_xchg(9), atomic_xchg_acquire(9),
atomic_xchg_release(9), atomic_xchg_relaxed(9), atomic_cmpxchg(9),
atomic_cmpxchg_acquire(9), atomic_cmpxchg_release(9),
atomic_cmpxchg_relaxed(9), atomic_try_cmpxchg(9),
atomic_try_cmpxchg_acquire(9), atomic_try_cmpxchg_release(9),
atomic_try_cmpxchg_relaxed(9), atomic_sub_and_test(9),
atomic_dec_and_test(9), atomic_inc_and_test(9), atomic_add_negative(9),
atomic_add_negative_acquire(9), atomic_add_negative_release(9),
atomic_add_negative_relaxed(9), atomic_fetch_add_unless(9),
atomic_add_unless(9), atomic_inc_not_zero(9),
atomic_inc_unless_negative(9), atomic_dec_unless_positive(9),
atomic_dec_if_positive(9), atomic64_read(9), atomic64_read_acquire(9),
atomic64_set(9), atomic64_set_release(9), atomic64_add(9),
atomic64_add_return(9), atomic64_add_return_acquire(9),
atomic64_add_return_release(9), atomic64_add_return_relaxed(9),
atomic64_fetch_add(9), atomic64_fetch_add_acquire(9),
atomic64_fetch_add_release(9), atomic64_fetch_add_relaxed(9),
atomic64_sub(9), atomic64_sub_return(9), atomic64_sub_return_acquire(9),
atomic64_sub_return_release(9), atomic64_sub_return_relaxed(9),
atomic64_fetch_sub(9), atomic64_fetch_sub_acquire(9),
atomic64_fetch_sub_release(9), atomic64_fetch_sub_relaxed(9),
atomic64_inc(9), atomic64_inc_return(9), atomic64_inc_return_acquire(9),
atomic64_inc_return_release(9), atomic64_inc_return_relaxed(9),
atomic64_fetch_inc(9), atomic64_fetch_inc_acquire(9),
atomic64_fetch_inc_release(9), atomic64_fetch_inc_relaxed(9),
atomic64_dec(9), atomic64_dec_return(9), atomic64_dec_return_acquire(9),
atomic64_dec_return_release(9), atomic64_dec_return_relaxed(9),
atomic64_fetch_dec(9), atomic64_fetch_dec_acquire(9),
atomic64_fetch_dec_release(9), atomic64_fetch_dec_relaxed(9),
atomic64_and(9), atomic64_fetch_and(9), atomic64_fetch_and_acquire(9),
atomic64_fetch_and_release(9), atomic64_fetch_and_relaxed(9),
atomic64_andnot(9), atomic64_fetch_andnot(9),
atomic64_fetch_andnot_acquire(9), atomic64_fetch_andnot_release(9),
atomic64_fetch_andnot_relaxed(9), atomic64_or(9), atomic64_fetch_or(9),
atomic64_fetch_or_acquire(9), atomic64_fetch_or_relaxed(9),
atomic64_xor(9), atomic64_fetch_xor(9), atomic64_fetch_xor_acquire(9),
atomic64_fetch_xor_release(9), atomic64_fetch_xor_relaxed(9),
atomic64_xchg(9), atomic64_xchg_acquire(9), atomic64_xchg_release(9),
atomic64_xchg_relaxed(9), atomic64_cmpxchg(9),
atomic64_cmpxchg_acquire(9), atomic64_cmpxchg_release(9),
atomic64_cmpxchg_relaxed(9), atomic64_try_cmpxchg(9),
atomic64_try_cmpxchg_acquire(9), atomic64_try_cmpxchg_release(9),
atomic64_try_cmpxchg_relaxed(9), atomic64_sub_and_test(9),
atomic64_dec_and_test(9), atomic64_inc_and_test(9),
atomic64_add_negative(9), atomic64_add_negative_acquire(9),
atomic64_add_negative_release(9), atomic64_add_negative_relaxed(9),
atomic64_fetch_add_unless(9), atomic64_add_unless(9),
atomic64_inc_not_zero(9), atomic64_inc_unless_negative(9),
atomic64_dec_unless_positive(9), atomic64_dec_if_positive(9),
atomic_long_read(9), atomic_long_read_acquire(9), atomic_long_set(9),
atomic_long_set_release(9), atomic_long_add(9),
atomic_long_add_return(9), atomic_long_add_return_acquire(9),
atomic_long_add_return_release(9), atomic_long_add_return_relaxed(9),
atomic_long_fetch_add(9), atomic_long_fetch_add_acquire(9),
atomic_long_fetch_add_release(9), atomic_long_fetch_add_relaxed(9),
atomic_long_sub(9), atomic_long_sub_return(9),
atomic_long_sub_return_acquire(9), atomic_long_sub_return_release(9),
atomic_long_sub_return_relaxed(9), atomic_long_fetch_sub(9),
atomic_long_fetch_sub_acquire(9), atomic_long_fetch_sub_release(9),
atomic_long_fetch_sub_relaxed(9), atomic_long_inc(9),
atomic_long_inc_return(9), atomic_long_inc_return_acquire(9),
atomic_long_inc_return_release(9), atomic_long_inc_return_relaxed(9),
atomic_long_fetch_inc(9), atomic_long_fetch_inc_acquire(9),
atomic_long_fetch_inc_release(9), atomic_long_fetch_inc_relaxed(9),
atomic_long_dec(9), atomic_long_dec_return(9),
atomic_long_dec_return_acquire(9), atomic_long_dec_return_release(9),
atomic_long_dec_return_relaxed(9), atomic_long_fetch_dec(9),
atomic_long_fetch_dec_acquire(9), atomic_long_fetch_dec_release(9),
atomic_long_fetch_dec_relaxed(9), atomic_long_and(9),
atomic_long_fetch_and(9), atomic_long_fetch_and_acquire(9),
atomic_long_fetch_and_release(9), atomic_long_fetch_and_relaxed(9),
atomic_long_andnot(9), atomic_long_fetch_andnot(9),
atomic_long_fetch_andnot_acquire(9),
atomic_long_fetch_andnot_release(9),
atomic_long_fetch_andnot_relaxed(9), atomic_long_or(9),
atomic_long_fetch_or(9), atomic_long_fetch_or_acquire(9),
atomic_long_fetch_or_release(9), atomic_long_fetch_or_relaxed(9),
atomic_long_xor(9), atomic_long_fetch_xor(9),
atomic_long_fetch_xor_acquire(9), atomic_long_fetch_xor_release(9),
atomic_long_fetch_xor_relaxed(9), atomic_long_xchg(9),
atomic_long_xchg_acquire(9), atomic_long_xchg_release(9),
atomic_long_xchg_relaxed(9), atomic_long_cmpxchg(9),
atomic_long_cmpxchg_acquire(9), atomic_long_cmpxchg_release(9),
atomic_long_cmpxchg_relaxed(9), atomic_long_try_cmpxchg(9),
atomic_long_try_cmpxchg_acquire(9), atomic_long_try_cmpxchg_release(9),
atomic_long_try_cmpxchg_relaxed(9), atomic_long_sub_and_test(9),
atomic_long_dec_and_test(9), atomic_long_inc_and_test(9),
atomic_long_add_negative(9), atomic_long_add_negative_acquire(9),
atomic_long_add_negative_release(9),
atomic_long_add_negative_relaxed(9), atomic_long_fetch_add_unless(9),
atomic_long_add_unless(9), atomic_long_inc_not_zero(9),
atomic_long_inc_unless_negative(9), atomic_long_dec_unless_positive(9),
atomic_long_dec_if_positive(9)

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okay and for the cute sign-off 🫶 this page came out of the source ./include/linux/atomic, stamped October 2026, and it's filed under atomic64_fetch_or_release(9) — that's the whole header-and-footer situation, wrapped in a bow 🎀 mwah, go OR something atomically bestie 💜