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author | Mark Rutland <mark.rutland@arm.com> | 2021-05-25 17:02:08 +0300 |
---|---|---|
committer | Peter Zijlstra <peterz@infradead.org> | 2021-05-26 14:20:50 +0300 |
commit | f8b6455a9d381fc513efbec0be0c312b96e6eb6b (patch) | |
tree | f48299d7cc768fb3cbe7d908a7b752019af1a5f7 /include | |
parent | d0e03218ca3be48c6f7109e4810d58e7b7dd4135 (diff) | |
download | linux-f8b6455a9d381fc513efbec0be0c312b96e6eb6b.tar.xz |
locking/atomic: atomic: support ARCH_ATOMIC
We'd like all architectures to convert to ARCH_ATOMIC, as this will
enable functionality, and once all architectures are converted it will
be possible to make significant cleanups to the atomic headers.
A number of architectures use asm-generic/atomic.h, and it's impractical
to convert the header and all these architectures in one go. To make it
possible to convert them one-by-one, let's make the asm-generic
implementation function as either atomic_*() or arch_atomic_*()
depending on whether ARCH_ATOMIC is selected. To do this, the C
implementations are prefixed as generic_atomic_*(), and preprocessor
definitions map atomic_*()/arch_atomic_*() onto these as
appropriate.
Once all users are moved over to ARCH_ATOMIC the ifdeffery in the header
can be simplified and/or removed entirely.
For existing users (none of which select ARCH_ATOMIC), there should be
no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210525140232.53872-10-mark.rutland@arm.com
Diffstat (limited to 'include')
-rw-r--r-- | include/asm-generic/atomic.h | 71 |
1 files changed, 62 insertions, 9 deletions
diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h index 316c82a27b0a..649060fa0fe8 100644 --- a/include/asm-generic/atomic.h +++ b/include/asm-generic/atomic.h @@ -12,39 +12,47 @@ #include <asm/cmpxchg.h> #include <asm/barrier.h> +#ifdef CONFIG_ARCH_ATOMIC +#define __ga_cmpxchg arch_cmpxchg +#define __ga_xchg arch_xchg +#else +#define __ga_cmpxchg cmpxchg +#define __ga_xchg xchg +#endif + #ifdef CONFIG_SMP /* we can build all atomic primitives from cmpxchg */ #define ATOMIC_OP(op, c_op) \ -static inline void atomic_##op(int i, atomic_t *v) \ +static inline void generic_atomic_##op(int i, atomic_t *v) \ { \ int c, old; \ \ c = v->counter; \ - while ((old = cmpxchg(&v->counter, c, c c_op i)) != c) \ + while ((old = __ga_cmpxchg(&v->counter, c, c c_op i)) != c) \ c = old; \ } #define ATOMIC_OP_RETURN(op, c_op) \ -static inline int atomic_##op##_return(int i, atomic_t *v) \ +static inline int generic_atomic_##op##_return(int i, atomic_t *v) \ { \ int c, old; \ \ c = v->counter; \ - while ((old = cmpxchg(&v->counter, c, c c_op i)) != c) \ + while ((old = __ga_cmpxchg(&v->counter, c, c c_op i)) != c) \ c = old; \ \ return c c_op i; \ } #define ATOMIC_FETCH_OP(op, c_op) \ -static inline int atomic_fetch_##op(int i, atomic_t *v) \ +static inline int generic_atomic_fetch_##op(int i, atomic_t *v) \ { \ int c, old; \ \ c = v->counter; \ - while ((old = cmpxchg(&v->counter, c, c c_op i)) != c) \ + while ((old = __ga_cmpxchg(&v->counter, c, c c_op i)) != c) \ c = old; \ \ return c; \ @@ -55,7 +63,7 @@ static inline int atomic_fetch_##op(int i, atomic_t *v) \ #include <linux/irqflags.h> #define ATOMIC_OP(op, c_op) \ -static inline void atomic_##op(int i, atomic_t *v) \ +static inline void generic_atomic_##op(int i, atomic_t *v) \ { \ unsigned long flags; \ \ @@ -65,7 +73,7 @@ static inline void atomic_##op(int i, atomic_t *v) \ } #define ATOMIC_OP_RETURN(op, c_op) \ -static inline int atomic_##op##_return(int i, atomic_t *v) \ +static inline int generic_atomic_##op##_return(int i, atomic_t *v) \ { \ unsigned long flags; \ int ret; \ @@ -78,7 +86,7 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \ } #define ATOMIC_FETCH_OP(op, c_op) \ -static inline int atomic_fetch_##op(int i, atomic_t *v) \ +static inline int generic_atomic_fetch_##op(int i, atomic_t *v) \ { \ unsigned long flags; \ int ret; \ @@ -112,10 +120,55 @@ ATOMIC_OP(xor, ^) #undef ATOMIC_OP_RETURN #undef ATOMIC_OP +#undef __ga_cmpxchg +#undef __ga_xchg + +#ifdef CONFIG_ARCH_ATOMIC + +#define arch_atomic_add_return generic_atomic_add_return +#define arch_atomic_sub_return generic_atomic_sub_return + +#define arch_atomic_fetch_add generic_atomic_fetch_add +#define arch_atomic_fetch_sub generic_atomic_fetch_sub +#define arch_atomic_fetch_and generic_atomic_fetch_and +#define arch_atomic_fetch_or generic_atomic_fetch_or +#define arch_atomic_fetch_xor generic_atomic_fetch_xor + +#define arch_atomic_add generic_atomic_add +#define arch_atomic_sub generic_atomic_sub +#define arch_atomic_and generic_atomic_and +#define arch_atomic_or generic_atomic_or +#define arch_atomic_xor generic_atomic_xor + +#define arch_atomic_read(v) READ_ONCE((v)->counter) +#define arch_atomic_set(v, i) WRITE_ONCE(((v)->counter), (i)) + +#define arch_atomic_xchg(ptr, v) (arch_xchg(&(ptr)->counter, (v))) +#define arch_atomic_cmpxchg(v, old, new) (arch_cmpxchg(&((v)->counter), (old), (new))) + +#else /* CONFIG_ARCH_ATOMIC */ + +#define atomic_add_return generic_atomic_add_return +#define atomic_sub_return generic_atomic_sub_return + +#define atomic_fetch_add generic_atomic_fetch_add +#define atomic_fetch_sub generic_atomic_fetch_sub +#define atomic_fetch_and generic_atomic_fetch_and +#define atomic_fetch_or generic_atomic_fetch_or +#define atomic_fetch_xor generic_atomic_fetch_xor + +#define atomic_add generic_atomic_add +#define atomic_sub generic_atomic_sub +#define atomic_and generic_atomic_and +#define atomic_or generic_atomic_or +#define atomic_xor generic_atomic_xor + #define atomic_read(v) READ_ONCE((v)->counter) #define atomic_set(v, i) WRITE_ONCE(((v)->counter), (i)) #define atomic_xchg(ptr, v) (xchg(&(ptr)->counter, (v))) #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new))) +#endif /* CONFIG_ARCH_ATOMIC */ + #endif /* __ASM_GENERIC_ATOMIC_H */ |