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/*
* Copyright IBM Corp. 1999, 2009
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
* Denis Joseph Barrow,
* Arnd Bergmann <arndb@de.ibm.com>,
*
* Atomic operations that C can't guarantee us.
* Useful for resource counting etc.
* s390 uses 'Compare And Swap' for atomicity in SMP environment.
*
*/
#ifndef __ARCH_S390_ATOMIC__
#define __ARCH_S390_ATOMIC__
#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/barrier.h>
#include <asm/cmpxchg.h>
#define ATOMIC_INIT(i) { (i) }
#define __ATOMIC_NO_BARRIER "\n"
#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
#define __ATOMIC_OR "lao"
#define __ATOMIC_AND "lan"
#define __ATOMIC_ADD "laa"
#define __ATOMIC_XOR "lax"
#define __ATOMIC_BARRIER "bcr 14,0\n"
#define __ATOMIC_LOOP(ptr, op_val, op_string, __barrier) \
({ \
int old_val; \
\
typecheck(atomic_t *, ptr); \
asm volatile( \
op_string " %0,%2,%1\n" \
__barrier \
: "=d" (old_val), "+Q" ((ptr)->counter) \
: "d" (op_val) \
: "cc", "memory"); \
old_val; \
})
#else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
#define __ATOMIC_OR "or"
#define __ATOMIC_AND "nr"
#define __ATOMIC_ADD "ar"
#define __ATOMIC_XOR "xr"
#define __ATOMIC_BARRIER "\n"
#define __ATOMIC_LOOP(ptr, op_val, op_string, __barrier) \
({ \
int old_val, new_val; \
\
typecheck(atomic_t *, ptr); \
asm volatile( \
" l %0,%2\n" \
"0: lr %1,%0\n" \
op_string " %1,%3\n" \
" cs %0,%1,%2\n" \
" jl 0b" \
: "=&d" (old_val), "=&d" (new_val), "+Q" ((ptr)->counter)\
: "d" (op_val) \
: "cc", "memory"); \
old_val; \
})
#endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
static inline int atomic_read(const atomic_t *v)
{
int c;
asm volatile(
" l %0,%1\n"
: "=d" (c) : "Q" (v->counter));
return c;
}
static inline void atomic_set(atomic_t *v, int i)
{
asm volatile(
" st %1,%0\n"
: "=Q" (v->counter) : "d" (i));
}
static inline int atomic_add_return(int i, atomic_t *v)
{
return __ATOMIC_LOOP(v, i, __ATOMIC_ADD, __ATOMIC_BARRIER) + i;
}
static inline void atomic_add(int i, atomic_t *v)
{
#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
if (__builtin_constant_p(i) && (i > -129) && (i < 128)) {
asm volatile(
"asi %0,%1\n"
: "+Q" (v->counter)
: "i" (i)
: "cc", "memory");
return;
}
#endif
__ATOMIC_LOOP(v, i, __ATOMIC_ADD, __ATOMIC_NO_BARRIER);
}
#define atomic_add_negative(_i, _v) (atomic_add_return(_i, _v) < 0)
#define atomic_inc(_v) atomic_add(1, _v)
#define atomic_inc_return(_v) atomic_add_return(1, _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_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) \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
__ATOMIC_LOOP(v, i, __ATOMIC_##OP, __ATOMIC_NO_BARRIER); \
}
ATOMIC_OP(and, AND)
ATOMIC_OP(or, OR)
ATOMIC_OP(xor, XOR)
#undef ATOMIC_OP
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
asm volatile(
" cs %0,%2,%1"
: "+d" (old), "+Q" (v->counter)
: "d" (new)
: "cc", "memory");
return old;
}
static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
for (;;) {
if (unlikely(c == u))
break;
old = atomic_cmpxchg(v, c, c + a);
if (likely(old == c))
break;
c = old;
}
return c;
}
#undef __ATOMIC_LOOP
#define ATOMIC64_INIT(i) { (i) }
#define __ATOMIC64_NO_BARRIER "\n"
#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
#define __ATOMIC64_OR "laog"
#define __ATOMIC64_AND "lang"
#define __ATOMIC64_ADD "laag"
#define __ATOMIC64_XOR "laxg"
#define __ATOMIC64_BARRIER "bcr 14,0\n"
#define __ATOMIC64_LOOP(ptr, op_val, op_string, __barrier) \
({ \
long long old_val; \
\
typecheck(atomic64_t *, ptr); \
asm volatile( \
op_string " %0,%2,%1\n" \
__barrier \
: "=d" (old_val), "+Q" ((ptr)->counter) \
: "d" (op_val) \
: "cc", "memory"); \
old_val; \
})
#else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
#define __ATOMIC64_OR "ogr"
#define __ATOMIC64_AND "ngr"
#define __ATOMIC64_ADD "agr"
#define __ATOMIC64_XOR "xgr"
#define __ATOMIC64_BARRIER "\n"
#define __ATOMIC64_LOOP(ptr, op_val, op_string, __barrier) \
({ \
long long old_val, new_val; \
\
typecheck(atomic64_t *, ptr); \
asm volatile( \
" lg %0,%2\n" \
"0: lgr %1,%0\n" \
op_string " %1,%3\n" \
" csg %0,%1,%2\n" \
" jl 0b" \
: "=&d" (old_val), "=&d" (new_val), "+Q" ((ptr)->counter)\
: "d" (op_val) \
: "cc", "memory"); \
old_val; \
})
#endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
static inline long long atomic64_read(const atomic64_t *v)
{
long long c;
asm volatile(
" lg %0,%1\n"
: "=d" (c) : "Q" (v->counter));
return c;
}
static inline void atomic64_set(atomic64_t *v, long long i)
{
asm volatile(
" stg %1,%0\n"
: "=Q" (v->counter) : "d" (i));
}
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 void atomic64_add(long long i, atomic64_t *v)
{
#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
if (__builtin_constant_p(i) && (i > -129) && (i < 128)) {
asm volatile(
"agsi %0,%1\n"
: "+Q" (v->counter)
: "i" (i)
: "cc", "memory");
return;
}
#endif
__ATOMIC64_LOOP(v, i, __ATOMIC64_ADD, __ATOMIC64_NO_BARRIER);
}
#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
static inline long long atomic64_cmpxchg(atomic64_t *v,
long long old, long long new)
{
asm volatile(
" csg %0,%2,%1"
: "+d" (old), "+Q" (v->counter)
: "d" (new)
: "cc", "memory");
return old;
}
#define ATOMIC64_OP(op, OP) \
static inline void atomic64_##op(long i, atomic64_t *v) \
{ \
__ATOMIC64_LOOP(v, i, __ATOMIC64_##OP, __ATOMIC64_NO_BARRIER); \
}
ATOMIC64_OP(and, AND)
ATOMIC64_OP(or, OR)
ATOMIC64_OP(xor, XOR)
#undef ATOMIC64_OP
#undef __ATOMIC64_LOOP
static inline int atomic64_add_unless(atomic64_t *v, long long i, long long u)
{
long long c, old;
c = atomic64_read(v);
for (;;) {
if (unlikely(c == u))
break;
old = atomic64_cmpxchg(v, c, c + i);
if (likely(old == c))
break;
c = old;
}
return c != u;
}
static inline long long atomic64_dec_if_positive(atomic64_t *v)
{
long long c, old, dec;
c = atomic64_read(v);
for (;;) {
dec = c - 1;
if (unlikely(dec < 0))
break;
old = atomic64_cmpxchg((v), c, dec);
if (likely(old == c))
break;
c = old;
}
return dec;
}
#define atomic64_add_negative(_i, _v) (atomic64_add_return(_i, _v) < 0)
#define atomic64_inc(_v) atomic64_add(1, _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_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)
#define atomic64_dec_return(_v) atomic64_sub_return(1, _v)
#define atomic64_dec_and_test(_v) (atomic64_sub_return(1, _v) == 0)
#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
#endif /* __ARCH_S390_ATOMIC__ */
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