git: 56557fd4c43a - stable/13 - linuxkpi: Add try_cmpxchg and atomic_try_cmpxchg
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Date: Wed, 07 Sep 2022 15:10:11 UTC
The branch stable/13 has been updated by manu: URL: https://cgit.FreeBSD.org/src/commit/?id=56557fd4c43a9fb25200f2afff7a557eb2028845 commit 56557fd4c43a9fb25200f2afff7a557eb2028845 Author: Emmanuel Vadot <manu@FreeBSD.org> AuthorDate: 2022-07-27 07:41:04 +0000 Commit: Emmanuel Vadot <manu@FreeBSD.org> CommitDate: 2022-09-07 15:09:03 +0000 linuxkpi: Add try_cmpxchg and atomic_try_cmpxchg Needed by drm-kmod Obtain from: drm-kmod Sponsored by: Beckhoff Automation GmbH & Co. KG Differential Revision: https://reviews.freebsd.org/D36015 (cherry picked from commit 39da3678b1ce2d4fac300e022e544b1db5c117c0) --- sys/compat/linuxkpi/common/include/asm/atomic.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/sys/compat/linuxkpi/common/include/asm/atomic.h b/sys/compat/linuxkpi/common/include/asm/atomic.h index 7c7a2c4d4b92..d7e5338c0356 100644 --- a/sys/compat/linuxkpi/common/include/asm/atomic.h +++ b/sys/compat/linuxkpi/common/include/asm/atomic.h @@ -268,6 +268,28 @@ atomic_cmpxchg(atomic_t *v, int old, int new) __ret.val; \ }) +#define try_cmpxchg(p, op, n) \ +({ \ + __typeof(p) __op = (__typeof((p)))(op); \ + __typeof(*(p)) __o = *__op; \ + __typeof(*(p)) __p = __sync_val_compare_and_swap((p), (__o), (n)); \ + if (__p != __o) \ + *__op = __p; \ + (__p == __o); \ +}) + +#define __atomic_try_cmpxchg(type, _p, _po, _n) \ +({ \ + __typeof(_po) __po = (_po); \ + __typeof(*(_po)) __r, __o = *__po; \ + __r = atomic_cmpxchg##type((_p), __o, (_n)); \ + if (unlikely(__r != __o)) \ + *__po = __r; \ + likely(__r == __o); \ +}) + +#define atomic_try_cmpxchg(_p, _po, _n) __atomic_try_cmpxchg(, _p, _po, _n) + static inline int atomic_dec_if_positive(atomic_t *v) {