diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2024-03-12 04:33:03 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2024-03-12 04:33:03 +0300 |
commit | a5b1a017cb76e4898dd62fcb97e8aee6a63b33b5 (patch) | |
tree | af38e275caeceed23ec5dea73cf71aa7818da75b /include/linux/atomic/atomic-arch-fallback.h | |
parent | b0402403e54ae9eb94ce1cbb53c7def776e97426 (diff) | |
parent | ce3576ebd62d99f79c1dc98824e2ef6d6ab68434 (diff) | |
download | linux-a5b1a017cb76e4898dd62fcb97e8aee6a63b33b5.tar.xz |
Merge tag 'locking-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
- Micro-optimize local_xchg() and the rtmutex code on x86
- Fix percpu-rwsem contention tracepoints
- Simplify debugging Kconfig dependencies
- Update/clarify the documentation of atomic primitives
- Misc cleanups
* tag 'locking-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/rtmutex: Use try_cmpxchg_relaxed() in mark_rt_mutex_waiters()
locking/x86: Implement local_xchg() using CMPXCHG without the LOCK prefix
locking/percpu-rwsem: Trigger contention tracepoints only if contended
locking/rwsem: Make DEBUG_RWSEMS and PREEMPT_RT mutually exclusive
locking/rwsem: Clarify that RWSEM_READER_OWNED is just a hint
locking/mutex: Simplify <linux/mutex.h>
locking/qspinlock: Fix 'wait_early' set but not used warning
locking/atomic: scripts: Clarify ordering of conditional atomics
Diffstat (limited to 'include/linux/atomic/atomic-arch-fallback.h')
-rw-r--r-- | include/linux/atomic/atomic-arch-fallback.h | 46 |
1 files changed, 37 insertions, 9 deletions
diff --git a/include/linux/atomic/atomic-arch-fallback.h b/include/linux/atomic/atomic-arch-fallback.h index 5e95faa959c4..956bcba5dbf2 100644 --- a/include/linux/atomic/atomic-arch-fallback.h +++ b/include/linux/atomic/atomic-arch-fallback.h @@ -2005,6 +2005,7 @@ raw_atomic_xchg_relaxed(atomic_t *v, int new) * @new: int value to assign * * If (@v == @old), atomically updates @v to @new with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_cmpxchg() elsewhere. * @@ -2033,6 +2034,7 @@ raw_atomic_cmpxchg(atomic_t *v, int old, int new) * @new: int value to assign * * If (@v == @old), atomically updates @v to @new with acquire ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_cmpxchg_acquire() elsewhere. * @@ -2061,6 +2063,7 @@ raw_atomic_cmpxchg_acquire(atomic_t *v, int old, int new) * @new: int value to assign * * If (@v == @old), atomically updates @v to @new with release ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_cmpxchg_release() elsewhere. * @@ -2088,6 +2091,7 @@ raw_atomic_cmpxchg_release(atomic_t *v, int old, int new) * @new: int value to assign * * If (@v == @old), atomically updates @v to @new with relaxed ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_cmpxchg_relaxed() elsewhere. * @@ -2112,7 +2116,8 @@ raw_atomic_cmpxchg_relaxed(atomic_t *v, int old, int new) * @new: int value to assign * * If (@v == @old), atomically updates @v to @new with full ordering. - * Otherwise, updates @old to the current value of @v. + * Otherwise, @v is not modified, @old is updated to the current value of @v, + * and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_try_cmpxchg() elsewhere. * @@ -2145,7 +2150,8 @@ raw_atomic_try_cmpxchg(atomic_t *v, int *old, int new) * @new: int value to assign * * If (@v == @old), atomically updates @v to @new with acquire ordering. - * Otherwise, updates @old to the current value of @v. + * Otherwise, @v is not modified, @old is updated to the current value of @v, + * and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_try_cmpxchg_acquire() elsewhere. * @@ -2178,7 +2184,8 @@ raw_atomic_try_cmpxchg_acquire(atomic_t *v, int *old, int new) * @new: int value to assign * * If (@v == @old), atomically updates @v to @new with release ordering. - * Otherwise, updates @old to the current value of @v. + * Otherwise, @v is not modified, @old is updated to the current value of @v, + * and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_try_cmpxchg_release() elsewhere. * @@ -2210,7 +2217,8 @@ raw_atomic_try_cmpxchg_release(atomic_t *v, int *old, int new) * @new: int value to assign * * If (@v == @old), atomically updates @v to @new with relaxed ordering. - * Otherwise, updates @old to the current value of @v. + * Otherwise, @v is not modified, @old is updated to the current value of @v, + * and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_try_cmpxchg_relaxed() elsewhere. * @@ -2403,6 +2411,7 @@ raw_atomic_add_negative_relaxed(int i, atomic_t *v) * @u: int value to compare with * * If (@v != @u), atomically updates @v to (@v + @a) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_fetch_add_unless() elsewhere. * @@ -2432,6 +2441,7 @@ raw_atomic_fetch_add_unless(atomic_t *v, int a, int u) * @u: int value to compare with * * If (@v != @u), atomically updates @v to (@v + @a) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_add_unless() elsewhere. * @@ -2452,6 +2462,7 @@ raw_atomic_add_unless(atomic_t *v, int a, int u) * @v: pointer to atomic_t * * If (@v != 0), atomically updates @v to (@v + 1) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_inc_not_zero() elsewhere. * @@ -2472,6 +2483,7 @@ raw_atomic_inc_not_zero(atomic_t *v) * @v: pointer to atomic_t * * If (@v >= 0), atomically updates @v to (@v + 1) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_inc_unless_negative() elsewhere. * @@ -2499,6 +2511,7 @@ raw_atomic_inc_unless_negative(atomic_t *v) * @v: pointer to atomic_t * * If (@v <= 0), atomically updates @v to (@v - 1) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_dec_unless_positive() elsewhere. * @@ -2526,6 +2539,7 @@ raw_atomic_dec_unless_positive(atomic_t *v) * @v: pointer to atomic_t * * If (@v > 0), atomically updates @v to (@v - 1) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic_dec_if_positive() elsewhere. * @@ -4117,6 +4131,7 @@ raw_atomic64_xchg_relaxed(atomic64_t *v, s64 new) * @new: s64 value to assign * * If (@v == @old), atomically updates @v to @new with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_cmpxchg() elsewhere. * @@ -4145,6 +4160,7 @@ raw_atomic64_cmpxchg(atomic64_t *v, s64 old, s64 new) * @new: s64 value to assign * * If (@v == @old), atomically updates @v to @new with acquire ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_cmpxchg_acquire() elsewhere. * @@ -4173,6 +4189,7 @@ raw_atomic64_cmpxchg_acquire(atomic64_t *v, s64 old, s64 new) * @new: s64 value to assign * * If (@v == @old), atomically updates @v to @new with release ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_cmpxchg_release() elsewhere. * @@ -4200,6 +4217,7 @@ raw_atomic64_cmpxchg_release(atomic64_t *v, s64 old, s64 new) * @new: s64 value to assign * * If (@v == @old), atomically updates @v to @new with relaxed ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_cmpxchg_relaxed() elsewhere. * @@ -4224,7 +4242,8 @@ raw_atomic64_cmpxchg_relaxed(atomic64_t *v, s64 old, s64 new) * @new: s64 value to assign * * If (@v == @old), atomically updates @v to @new with full ordering. - * Otherwise, updates @old to the current value of @v. + * Otherwise, @v is not modified, @old is updated to the current value of @v, + * and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_try_cmpxchg() elsewhere. * @@ -4257,7 +4276,8 @@ raw_atomic64_try_cmpxchg(atomic64_t *v, s64 *old, s64 new) * @new: s64 value to assign * * If (@v == @old), atomically updates @v to @new with acquire ordering. - * Otherwise, updates @old to the current value of @v. + * Otherwise, @v is not modified, @old is updated to the current value of @v, + * and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_try_cmpxchg_acquire() elsewhere. * @@ -4290,7 +4310,8 @@ raw_atomic64_try_cmpxchg_acquire(atomic64_t *v, s64 *old, s64 new) * @new: s64 value to assign * * If (@v == @old), atomically updates @v to @new with release ordering. - * Otherwise, updates @old to the current value of @v. + * Otherwise, @v is not modified, @old is updated to the current value of @v, + * and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_try_cmpxchg_release() elsewhere. * @@ -4322,7 +4343,8 @@ raw_atomic64_try_cmpxchg_release(atomic64_t *v, s64 *old, s64 new) * @new: s64 value to assign * * If (@v == @old), atomically updates @v to @new with relaxed ordering. - * Otherwise, updates @old to the current value of @v. + * Otherwise, @v is not modified, @old is updated to the current value of @v, + * and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_try_cmpxchg_relaxed() elsewhere. * @@ -4515,6 +4537,7 @@ raw_atomic64_add_negative_relaxed(s64 i, atomic64_t *v) * @u: s64 value to compare with * * If (@v != @u), atomically updates @v to (@v + @a) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_fetch_add_unless() elsewhere. * @@ -4544,6 +4567,7 @@ raw_atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u) * @u: s64 value to compare with * * If (@v != @u), atomically updates @v to (@v + @a) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_add_unless() elsewhere. * @@ -4564,6 +4588,7 @@ raw_atomic64_add_unless(atomic64_t *v, s64 a, s64 u) * @v: pointer to atomic64_t * * If (@v != 0), atomically updates @v to (@v + 1) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_inc_not_zero() elsewhere. * @@ -4584,6 +4609,7 @@ raw_atomic64_inc_not_zero(atomic64_t *v) * @v: pointer to atomic64_t * * If (@v >= 0), atomically updates @v to (@v + 1) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_inc_unless_negative() elsewhere. * @@ -4611,6 +4637,7 @@ raw_atomic64_inc_unless_negative(atomic64_t *v) * @v: pointer to atomic64_t * * If (@v <= 0), atomically updates @v to (@v - 1) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_dec_unless_positive() elsewhere. * @@ -4638,6 +4665,7 @@ raw_atomic64_dec_unless_positive(atomic64_t *v) * @v: pointer to atomic64_t * * If (@v > 0), atomically updates @v to (@v - 1) with full ordering. + * Otherwise, @v is not modified and relaxed ordering is provided. * * Safe to use in noinstr code; prefer atomic64_dec_if_positive() elsewhere. * @@ -4662,4 +4690,4 @@ raw_atomic64_dec_if_positive(atomic64_t *v) } #endif /* _LINUX_ATOMIC_FALLBACK_H */ -// eec048affea735b8464f58e6d96992101f8f85f1 +// 14850c0b0db20c62fdc78ccd1d42b98b88d76331 |