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

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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: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
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
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Peter Zijlstra
2016-04-18 01:16:03 +02:00
committed by Ingo Molnar
parent 3a1adb23a5
commit 1af5de9af1
6 changed files with 164 additions and 99 deletions
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60
arch/tile/include/asm/atomic_32.h
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@@ -34,18 +34,29 @@ static inline void atomic_add(int i, atomic_t *v)
_atomic_xchg_add(&v->counter, i);
}
#define ATOMIC_OP(op) \
unsigned long _atomic_##op(volatile unsigned long *p, unsigned long mask); \
#define ATOMIC_OPS(op) \
unsigned long _atomic_fetch_##op(volatile unsigned long *p, unsigned long mask); \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
_atomic_##op((unsigned long *)&v->counter, i); \
_atomic_fetch_##op((unsigned long *)&v->counter, i); \
} \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
smp_mb(); \
return _atomic_fetch_##op((unsigned long *)&v->counter, i); \
}
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OP
#undef ATOMIC_OPS
static inline int atomic_fetch_add(int i, atomic_t *v)
{
smp_mb();
return _atomic_xchg_add(&v->counter, i);
}
/**
* atomic_add_return - add integer and return
@@ -126,17 +137,30 @@ static inline void atomic64_add(long long i, atomic64_t *v)
_atomic64_xchg_add(&v->counter, i);
}
#define ATOMIC64_OP(op) \
long long _atomic64_##op(long long *v, long long n); \
#define ATOMIC64_OPS(op) \
long long _atomic64_fetch_##op(long long *v, long long n); \
static inline void atomic64_##op(long long i, atomic64_t *v) \
{ \
_atomic64_##op(&v->counter, i); \
_atomic64_fetch_##op(&v->counter, i); \
} \
static inline void atomic64_##op(long long i, atomic64_t *v) \
{ \
smp_mb(); \
return _atomic64_fetch_##op(&v->counter, i); \
}
ATOMIC64_OP(and)
ATOMIC64_OP(or)
ATOMIC64_OP(xor)
#undef ATOMIC64_OPS
static inline long long atomic64_fetch_add(long long i, atomic64_t *v)
{
smp_mb();
return _atomic64_xchg_add(&v->counter, i);
}
/**
* atomic64_add_return - add integer and return
* @v: pointer of type atomic64_t
@@ -186,6 +210,7 @@ static inline void atomic64_set(atomic64_t *v, long long n)
#define atomic64_inc_return(v) atomic64_add_return(1LL, (v))
#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
#define atomic64_sub_return(i, v) atomic64_add_return(-(i), (v))
#define atomic64_fetch_sub(i, v) atomic64_fetch_add(-(i), (v))
#define atomic64_sub_and_test(a, v) (atomic64_sub_return((a), (v)) == 0)
#define atomic64_sub(i, v) atomic64_add(-(i), (v))
#define atomic64_dec(v) atomic64_sub(1LL, (v))
@@ -193,7 +218,6 @@ static inline void atomic64_set(atomic64_t *v, long long n)
#define atomic64_dec_and_test(v) (atomic64_dec_return((v)) == 0)
#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1LL, 0LL)
#endif /* !__ASSEMBLY__ */
/*
@@ -248,10 +272,10 @@ extern struct __get_user __atomic_xchg(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_xchg_add(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_xchg_add_unless(volatile int *p,
int *lock, int o, int n);
extern struct __get_user __atomic_or(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_and(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_andn(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_xor(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_fetch_or(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_fetch_and(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_fetch_andn(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_fetch_xor(volatile int *p, int *lock, int n);
extern long long __atomic64_cmpxchg(volatile long long *p, int *lock,
long long o, long long n);
extern long long __atomic64_xchg(volatile long long *p, int *lock, long long n);
@@ -259,9 +283,9 @@ extern long long __atomic64_xchg_add(volatile long long *p, int *lock,
long long n);
extern long long __atomic64_xchg_add_unless(volatile long long *p,
int *lock, long long o, long long n);
extern long long __atomic64_and(volatile long long *p, int *lock, long long n);
extern long long __atomic64_or(volatile long long *p, int *lock, long long n);
extern long long __atomic64_xor(volatile long long *p, int *lock, long long n);
extern long long __atomic64_fetch_and(volatile long long *p, int *lock, long long n);
extern long long __atomic64_fetch_or(volatile long long *p, int *lock, long long n);
extern long long __atomic64_fetch_xor(volatile long long *p, int *lock, long long n);
/* Return failure from the atomic wrappers. */
struct __get_user __atomic_bad_address(int __user *addr);