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locking/atomic, arch/s390: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() 

Implement FETCH-OP atomic primitives, these are very similar to the
existing OP-RETURN primitives we already have, except they return the
value of the atomic variable _before_ modification.

This is especially useful for irreversible operations -- such as
bitops (because it becomes impossible to reconstruct the state prior
to modification).

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Peter Zijlstra 2016-04-18 01:16:05 +02:00 committed by Ingo Molnar
parent a28cc7bbe8
commit 56fefbbc3f
1 changed files with 32 additions and 10 deletions
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42
arch/s390/include/asm/atomic.h
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@ -93,6 +93,11 @@ static inline int atomic_add_return(int i, atomic_t *v)
return __ATOMIC_LOOP(v, i, __ATOMIC_ADD, __ATOMIC_BARRIER) + i;
}
static inline int atomic_fetch_add(int i, atomic_t *v)
{
return __ATOMIC_LOOP(v, i, __ATOMIC_ADD, __ATOMIC_BARRIER);
}
static inline void atomic_add(int i, atomic_t *v)
{
#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
@ -114,22 +119,29 @@ static inline void atomic_add(int i, atomic_t *v)
#define atomic_inc_and_test(_v) (atomic_add_return(1, _v) == 0)
#define atomic_sub(_i, _v) atomic_add(-(int)(_i), _v)
#define atomic_sub_return(_i, _v) atomic_add_return(-(int)(_i), _v)
#define atomic_fetch_sub(_i, _v) atomic_fetch_add(-(int)(_i), _v)
#define atomic_sub_and_test(_i, _v) (atomic_sub_return(_i, _v) == 0)
#define atomic_dec(_v) atomic_sub(1, _v)
#define atomic_dec_return(_v) atomic_sub_return(1, _v)
#define atomic_dec_and_test(_v) (atomic_sub_return(1, _v) == 0)
#define ATOMIC_OP(op, OP) \
#define ATOMIC_OPS(op, OP) \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
__ATOMIC_LOOP(v, i, __ATOMIC_##OP, __ATOMIC_NO_BARRIER); \
} \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
return __ATOMIC_LOOP(v, i, __ATOMIC_##OP, __ATOMIC_BARRIER); \
}
ATOMIC_OP(and, AND)
ATOMIC_OP(or, OR)
ATOMIC_OP(xor, XOR)
#define atomic_fetch_or atomic_fetch_or
#undef ATOMIC_OP
ATOMIC_OPS(and, AND)
ATOMIC_OPS(or, OR)
ATOMIC_OPS(xor, XOR)
#undef ATOMIC_OPS
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
@ -236,6 +248,11 @@ static inline long long atomic64_add_return(long long i, atomic64_t *v)
return __ATOMIC64_LOOP(v, i, __ATOMIC64_ADD, __ATOMIC64_BARRIER) + i;
}
static inline long long atomic64_fetch_add(long long i, atomic64_t *v)
{
return __ATOMIC64_LOOP(v, i, __ATOMIC64_ADD, __ATOMIC64_BARRIER);
}
static inline void atomic64_add(long long i, atomic64_t *v)
{
#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
@ -264,17 +281,21 @@ static inline long long atomic64_cmpxchg(atomic64_t *v,
return old;
}
#define ATOMIC64_OP(op, OP) \
#define ATOMIC64_OPS(op, OP) \
static inline void atomic64_##op(long i, atomic64_t *v) \
{ \
__ATOMIC64_LOOP(v, i, __ATOMIC64_##OP, __ATOMIC64_NO_BARRIER); \
} \
static inline long atomic64_fetch_##op(long i, atomic64_t *v) \
{ \
return __ATOMIC64_LOOP(v, i, __ATOMIC64_##OP, __ATOMIC64_BARRIER); \
}
ATOMIC64_OP(and, AND)
ATOMIC64_OP(or, OR)
ATOMIC64_OP(xor, XOR)
ATOMIC64_OPS(and, AND)
ATOMIC64_OPS(or, OR)
ATOMIC64_OPS(xor, XOR)
#undef ATOMIC64_OP
#undef ATOMIC64_OPS
#undef __ATOMIC64_LOOP
static inline int atomic64_add_unless(atomic64_t *v, long long i, long long u)
@ -315,6 +336,7 @@ static inline long long atomic64_dec_if_positive(atomic64_t *v)
#define atomic64_inc_return(_v) atomic64_add_return(1, _v)
#define atomic64_inc_and_test(_v) (atomic64_add_return(1, _v) == 0)
#define atomic64_sub_return(_i, _v) atomic64_add_return(-(long long)(_i), _v)
#define atomic64_fetch_sub(_i, _v) atomic64_fetch_add(-(long long)(_i), _v)
#define atomic64_sub(_i, _v) atomic64_add(-(long long)(_i), _v)
#define atomic64_sub_and_test(_i, _v) (atomic64_sub_return(_i, _v) == 0)
#define atomic64_dec(_v) atomic64_sub(1, _v)