atomic_try_cmpxchg_release(9)
π¦ atomic_try_cmpxchg_release(9) β the Kernel API Manual glow-up π¦
okay so bestie, welcome to the <pink>Kernel API Manual</pink> entry for atomic_try_cmpxchg_release, and no cap, this one is kind of a baddie. it does an atomic compare-and-exchange, but with release ordering, which is the whole vibe. let's get into it π
β¨ NAME β¨
atomic_try_cmpxchg_release β atomic compare and exchange with release ordering π
πΈ SYNOPSIS πΈ
bool atomic_try_cmpxchg_release (atomic_t *v , int *old , int new );
like, that's the whole signature. short. iconic. to the point. π
π«Ά ARGUMENTS π«Ά
vβ pointer toatomic_t. this is the atomic thing we're looking at, bestie π§oldβ pointer to anintvalue to compare with. yes, it's a pointer, she's not just a value, she's a whole address π₯newβ theintvalue to assign. the glow-up value, if you will β¨
π DESCRIPTION π
so here's the tea. if (v == old), then it atomically updates v to new with release ordering. periodt. π
otherwise? v is not modified, old gets updated to the current value of v, and relaxed ordering is provided. so it's giving "we didn't match, but here's the actual value, you're welcome" π
β οΈ okay real talk, this is unsafe to use innoinstrcode. useraw_atomic_try_cmpxchg_releasethere instead. don't be the main character who ignores this, fr fr π
π RETURN π
trueβ if the exchange occurred πfalseβ otherwise π
that's it. that's the answer. boolean baddie energy β
π SEE ALSO π
the kernel file is ./include/linux/atomic/atomic-instrumented.h, and honestly the squad it rolls with is huge. like, everybody's here. iykyk π
the atomic_* girlies:
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_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)
the atomic64_* crew, living their 64-bit truth:
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_release(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)
and the atomic_long_* icons, long may they reign:
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)
likeβ¦ that's the whole family reunion and everybody ate ππ
and that's the page, bestie! this little masterpiece lives over at ./include/linux/atomic, it's dated October 2026, and it's filed under atomic_try_cmpxchg_release(9) β go off, you atomic icon ππβ¨
π¦ where this page comes from
- nixpkgs unstable: linux-manual 7.3.1
- π girlified by deepseek-ai/DeepSeek-V4.1-Flash-1017 on : a language model's rewrite of the original, under its terms