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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-long.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-long.h')
-rw-r--r-- | include/linux/atomic/atomic-long.h | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/include/linux/atomic/atomic-long.h b/include/linux/atomic/atomic-long.h index c82947170ddc..3ef844b3ab8a 100644 --- a/include/linux/atomic/atomic-long.h +++ b/include/linux/atomic/atomic-long.h @@ -1352,6 +1352,7 @@ raw_atomic_long_xchg_relaxed(atomic_long_t *v, long new) * @new: long 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_long_cmpxchg() elsewhere. * @@ -1374,6 +1375,7 @@ raw_atomic_long_cmpxchg(atomic_long_t *v, long old, long new) * @new: long 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_long_cmpxchg_acquire() elsewhere. * @@ -1396,6 +1398,7 @@ raw_atomic_long_cmpxchg_acquire(atomic_long_t *v, long old, long new) * @new: long 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_long_cmpxchg_release() elsewhere. * @@ -1418,6 +1421,7 @@ raw_atomic_long_cmpxchg_release(atomic_long_t *v, long old, long new) * @new: long 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_long_cmpxchg_relaxed() elsewhere. * @@ -1440,7 +1444,8 @@ raw_atomic_long_cmpxchg_relaxed(atomic_long_t *v, long old, long new) * @new: long 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_long_try_cmpxchg() elsewhere. * @@ -1463,7 +1468,8 @@ raw_atomic_long_try_cmpxchg(atomic_long_t *v, long *old, long new) * @new: long 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_long_try_cmpxchg_acquire() elsewhere. * @@ -1486,7 +1492,8 @@ raw_atomic_long_try_cmpxchg_acquire(atomic_long_t *v, long *old, long new) * @new: long 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_long_try_cmpxchg_release() elsewhere. * @@ -1509,7 +1516,8 @@ raw_atomic_long_try_cmpxchg_release(atomic_long_t *v, long *old, long new) * @new: long 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_long_try_cmpxchg_relaxed() elsewhere. * @@ -1677,6 +1685,7 @@ raw_atomic_long_add_negative_relaxed(long i, atomic_long_t *v) * @u: long 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_long_fetch_add_unless() elsewhere. * @@ -1699,6 +1708,7 @@ raw_atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u) * @u: long 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_long_add_unless() elsewhere. * @@ -1719,6 +1729,7 @@ raw_atomic_long_add_unless(atomic_long_t *v, long a, long u) * @v: pointer to atomic_long_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_long_inc_not_zero() elsewhere. * @@ -1739,6 +1750,7 @@ raw_atomic_long_inc_not_zero(atomic_long_t *v) * @v: pointer to atomic_long_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_long_inc_unless_negative() elsewhere. * @@ -1759,6 +1771,7 @@ raw_atomic_long_inc_unless_negative(atomic_long_t *v) * @v: pointer to atomic_long_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_long_dec_unless_positive() elsewhere. * @@ -1779,6 +1792,7 @@ raw_atomic_long_dec_unless_positive(atomic_long_t *v) * @v: pointer to atomic_long_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_long_dec_if_positive() elsewhere. * @@ -1795,4 +1809,4 @@ raw_atomic_long_dec_if_positive(atomic_long_t *v) } #endif /* _LINUX_ATOMIC_LONG_H */ -// 4ef23f98c73cff96d239896175fd26b10b88899e +// 1c4a26fc77f345342953770ebe3c4d08e7ce2f9a |