raw_atomic64...xchg_acquire(9)

💅 raw_atomic64...xchg_acquire(9) — Kernel API Manual 🎀

ok so bestie, welcome to the Kernel API Manual, page raw_atomic64...xchg_acquire(9). yes the page name and the NAME line don't match, no i will not be explaining that, it's giving "the docs contain multitudes" ✨ anyway, buckle up, we're doing atomics 🦋

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✨ NAME ✨

raw_atomic64_cmpxchg_acquire — atomic compare and exchange with acquire ordering. she compares, she exchanges, she does it atomically, she's booked and busy 💅

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🌸 SYNOPSIS 🌸

s64 raw_atomic64_cmpxchg_acquire (atomic64_t *v , s64 old , s64 new );

like the signature says, bestie: three args, one s64 coming back at you 🫶

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🎀 ARGUMENTS 🎀

• v — pointer to atomic64_t. this is the thing we're messing with, the main character of the operation 👑
• old — an s64 value to compare with. the vibe check value, if you will 💖
• new — an s64 value to assign. the glow-up we're applying if the vibe check passes ✨

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💜 DESCRIPTION 💜

ok so the actual logic, listen closely:

If (v == old), it atomically updates v to new with acquire ordering. slay, the exchange happened 💅

Otherwise, v is not modified and relaxed ordering is provided. no change, no drama, just vibes 🌈

⭐ real talk though: this one is safe to use in noinstr code; prefer atomic64_cmpxchg_acquire elsewhere. iykwim — it's the special-occasion tool, not the everyday one 🙈

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🦋 RETURN 🦋

The original value of v. that's it, that's the return — the before picture, the pre-makeover selfie 😭📸

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🌟 SEE ALSO 🌟

the whole extended friend group, fr fr — no gatekeeping here 🫶

Kernel file ./include/linux/atomic/atomic-arch-fallback.h
raw_atomic_read(9), raw_atomic_read_acquire(9), raw_atomic_set(9),
raw_atomic_set_release(9), raw_atomic_add(9), raw_atomic_add_return(9),
raw_atomic_add_return_acquire(9), raw_atomic_add_return_release(9),
raw_atomic_add_return_relaxed(9), raw_atomic_fetch_add(9),
raw_atomic_fetch_add_acquire(9), raw_atomic_fetch_add_release(9),
raw_atomic_fetch_add_relaxed(9), raw_atomic_sub(9),
raw_atomic_sub_return(9), raw_atomic_sub_return_acquire(9),
raw_atomic_sub_return_release(9), raw_atomic_sub_return_relaxed(9),
raw_atomic_fetch_sub(9), raw_atomic_fetch_sub_acquire(9),
raw_atomic_fetch_sub_release(9), raw_atomic_fetch_sub_relaxed(9),
raw_atomic_inc(9), raw_atomic_inc_return(9),
raw_atomic_inc_return_acquire(9), raw_atomic_inc_return_release(9),
raw_atomic_inc_return_relaxed(9), raw_atomic_fetch_inc(9),
raw_atomic_fetch_inc_acquire(9), raw_atomic_fetch_inc_release(9),
raw_atomic_fetch_inc_relaxed(9), raw_atomic_dec(9),
raw_atomic_dec_return(9), raw_atomic_dec_return_acquire(9),
raw_atomic_dec_return_release(9), raw_atomic_dec_return_relaxed(9),
raw_atomic_fetch_dec(9), raw_atomic_fetch_dec_acquire(9),
raw_atomic_fetch_dec_release(9), raw_atomic_fetch_dec_relaxed(9),
raw_atomic_and(9), raw_atomic_fetch_and(9),
raw_atomic_fetch_and_acquire(9), raw_atomic_fetch_and_release(9),
raw_atomic_fetch_and_relaxed(9), raw_atomic_andnot(9),
raw_atomic_fetch_andnot(9), raw_atomic_fetch_andnot_acquire(9),
raw_atomic_fetch_andnot_release(9), raw_atomic_fetch_andnot_relaxed(9),
raw_atomic_or(9), raw_atomic_fetch_or(9),
raw_atomic_fetch_or_acquire(9), raw_atomic_fetch_or_release(9),
raw_atomic_fetch_or_relaxed(9), raw_atomic_xor(9),
raw_atomic_fetch_xor(9), raw_atomic_fetch_xor_acquire(9),
raw_atomic_fetch_xor_release(9), raw_atomic_fetch_xor_relaxed(9),
raw_atomic_xchg(9), raw_atomic_xchg_acquire(9),
raw_atomic_xchg_release(9), raw_atomic_xchg_relaxed(9),
raw_atomic_cmpxchg(9), raw_atomic_cmpxchg_acquire(9),
raw_atomic_cmpxchg_release(9), raw_atomic_cmpxchg_relaxed(9),
raw_atomic_try_cmpxchg(9), raw_atomic_try_cmpxchg_acquire(9),
raw_atomic_try_cmpxchg_release(9), raw_atomic_try_cmpxchg_relaxed(9),
raw_atomic_sub_and_test(9), raw_atomic_dec_and_test(9),
raw_atomic_inc_and_test(9), raw_atomic_add_negative(9),
raw_atomic_add_negative_acquire(9), raw_atomic_add_negative_release(9),
raw_atomic_add_negative_relaxed(9), raw_atomic_fetch_add_unless(9),
raw_atomic_add_unless(9), raw_atomic_inc_not_zero(9),
raw_atomic_inc_unless_negative(9), raw_atomic_dec_unless_positive(9),
raw_atomic_dec_if_positive(9), raw_atomic64_read(9),
raw_atomic64_read_acquire(9), raw_atomic64_set(9),
raw_atomic64_set_release(9), raw_atomic64_add(9),
raw_atomic64_add_return(9), raw_atomic64_add_return_acquire(9),
raw_atomic64_add_return_release(9), raw_atomic64_add_return_relaxed(9),
raw_atomic64_fetch_add(9), raw_atomic64_fetch_add_acquire(9),
raw_atomic64_fetch_add_release(9), raw_atomic64_fetch_add_relaxed(9),
raw_atomic64_sub(9), raw_atomic64_sub_return(9),
raw_atomic64_sub_return_acquire(9), raw_atomic64_sub_return_release(9),
raw_atomic64_sub_return_relaxed(9), raw_atomic64_fetch_sub(9),
raw_atomic64_fetch_sub_acquire(9), raw_atomic64_fetch_sub_release(9),
raw_atomic64_fetch_sub_relaxed(9), raw_atomic64_inc(9),
raw_atomic64_inc_return(9), raw_atomic64_inc_return_acquire(9),
raw_atomic64_inc_return_release(9), raw_atomic64_inc_return_relaxed(9),
raw_atomic64_fetch_inc(9), raw_atomic64_fetch_inc_acquire(9),
raw_atomic64_fetch_inc_release(9), raw_atomic64_fetch_inc_relaxed(9),
raw_atomic64_dec(9), raw_atomic64_dec_return(9),
raw_atomic64_dec_return_acquire(9), raw_atomic64_dec_return_release(9),
raw_atomic64_dec_return_relaxed(9), raw_atomic64_fetch_dec(9),
raw_atomic64_fetch_dec_acquire(9), raw_atomic64_fetch_dec_release(9),
raw_atomic64_fetch_dec_relaxed(9), raw_atomic64_and(9),
raw_atomic64_fetch_and(9), raw_atomic64_fetch_and_acquire(9),
raw_atomic64_fetch_and_release(9), raw_atomic64_fetch_and_relaxed(9),
raw_atomic64_andnot(9), raw_atomic64_fetch_andnot(9),
raw_atomic64_fetch_andnot_acquire(9),
raw_atomic64_fetch_andnot_release(9),
raw_atomic64_fetch_andnot_relaxed(9), raw_atomic64_or(9),
raw_atomic64_fetch_or(9), raw_atomic64_fetch_or_acquire(9),
raw_atomic64_fetch_or_release(9), raw_atomic64_fetch_or_relaxed(9),
raw_atomic64_xor(9), raw_atomic64_fetch_xor(9),
raw_atomic64_fetch_xor_acquire(9), raw_atomic64_fetch_xor_release(9),
raw_atomic64_fetch_xor_relaxed(9), raw_atomic64_xchg(9),
raw_atomic64_xchg_acquire(9), raw_atomic64_xchg_release(9),
raw_atomic64_xchg_relaxed(9), raw_atomic64_cmpxchg(9),
raw_atomic64_cmpxchg_release(9), raw_atomic64_cmpxchg_relaxed(9),
raw_atomic64_try_cmpxchg(9), raw_atomic64_try_cmpxchg_acquire(9),
raw_atomic64_try_cmpxchg_release(9),
raw_atomic64_try_cmpxchg_relaxed(9), raw_atomic64_sub_and_test(9),
raw_atomic64_dec_and_test(9), raw_atomic64_inc_and_test(9),
raw_atomic64_add_negative(9), raw_atomic64_add_negative_acquire(9),
raw_atomic64_add_negative_release(9),
raw_atomic64_add_negative_relaxed(9), raw_atomic64_fetch_add_unless(9),
raw_atomic64_add_unless(9), raw_atomic64_inc_not_zero(9),
raw_atomic64_inc_unless_negative(9),
raw_atomic64_dec_unless_positive(9), raw_atomic64_dec_if_positive(9)

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and that's the whole page, bestie, we ate and left zero crumbs 💅✨ this cutie lives in ./include/linux/atomic and was served fresh October 2026 — mwah, drink water, and go read your atomics 🍓💖🦋