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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
[S390] atomic: use inline asm
Use inline assemblies for atomic_read/set(). This way there shouldn't
be any questions or subtle volatile semantics left.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
authored by Heiko Carstens and committed by Martin Schwidefsky 7657e41a a8c8d7c6
+18
-4
arch/s390/include/asm/atomic.h
+18
-4
arch/s390/include/asm/atomic.h
···
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static inline int atomic_read(const atomic_t *v)
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{
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return ACCESS_ONCE(v->counter);
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int c;
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+
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asm volatile(
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" l %0,%1\n"
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: "=d" (c) : "Q" (v->counter));
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return c;
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}
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static inline void atomic_set(atomic_t *v, int i)
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{
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v->counter = i;
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asm volatile(
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" st %1,%0\n"
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: "=Q" (v->counter) : "d" (i));
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}
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static inline int atomic_add_return(int i, atomic_t *v)
···
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static inline long long atomic64_read(const atomic64_t *v)
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{
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return ACCESS_ONCE(v->counter);
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long long c;
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+
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asm volatile(
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" lg %0,%1\n"
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: "=d" (c) : "Q" (v->counter));
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return c;
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}
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static inline void atomic64_set(atomic64_t *v, long long i)
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{
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v->counter = i;
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asm volatile(
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" stg %1,%0\n"
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: "=Q" (v->counter) : "d" (i));
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}
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static inline long long atomic64_add_return(long long i, atomic64_t *v)