freebsd-nq/sys/alpha/include/atomic.h
John Baldwin 3c2bc2bf26 Add a new atomic_fetchadd() primitive that atomically adds a value to a
variable and returns the previous value of the variable.

Tested on:	i386, alpha, sparc64, arm (cognet)
Reviewed by:	arch@
Submitted by:	cognet (arm)
MFC after:	1 week
2005-09-27 17:39:11 +00:00

479 lines
14 KiB
C

/*-
* Copyright (c) 1998 Doug Rabson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _MACHINE_ATOMIC_H_
#define _MACHINE_ATOMIC_H_
#ifndef _SYS_CDEFS_H_
#error this file needs sys/cdefs.h as a prerequisite
#endif
#include <machine/alpha_cpu.h>
/*
* Various simple arithmetic on memory which is atomic in the presence
* of interrupts and SMP safe.
*/
void atomic_set_8(volatile u_int8_t *, u_int8_t);
void atomic_clear_8(volatile u_int8_t *, u_int8_t);
void atomic_add_8(volatile u_int8_t *, u_int8_t);
void atomic_subtract_8(volatile u_int8_t *, u_int8_t);
void atomic_set_16(volatile u_int16_t *, u_int16_t);
void atomic_clear_16(volatile u_int16_t *, u_int16_t);
void atomic_add_16(volatile u_int16_t *, u_int16_t);
void atomic_subtract_16(volatile u_int16_t *, u_int16_t);
static __inline void atomic_set_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t temp;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"1:\tldl_l %0, %3\n\t" /* load old value */
"bis %0, %2, %0\n\t" /* calculate new value */
"stl_c %0, %1\n\t" /* attempt to store */
"beq %0, 1b\n" /* spin if failed */
: "=&r" (temp), "=m" (*p)
: "r" (v), "m" (*p)
: "memory");
#endif
}
static __inline void atomic_clear_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t temp;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"1:\tldl_l %0, %3\n\t" /* load old value */
"bic %0, %2, %0\n\t" /* calculate new value */
"stl_c %0, %1\n\t" /* attempt to store */
"beq %0, 1b\n" /* spin if failed */
: "=&r" (temp), "=m" (*p)
: "r" (v), "m" (*p)
: "memory");
#endif
}
static __inline void atomic_add_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t temp;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"1:\tldl_l %0, %3\n\t" /* load old value */
"addl %0, %2, %0\n\t" /* calculate new value */
"stl_c %0, %1\n\t" /* attempt to store */
"beq %0, 1b\n" /* spin if failed */
: "=&r" (temp), "=m" (*p)
: "r" (v), "m" (*p)
: "memory");
#endif
}
static __inline void atomic_subtract_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t temp;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"1:\tldl_l %0, %3\n\t" /* load old value */
"subl %0, %2, %0\n\t" /* calculate new value */
"stl_c %0, %1\n\t" /* attempt to store */
"beq %0, 1b\n" /* spin if failed */
: "=&r" (temp), "=m" (*p)
: "r" (v), "m" (*p)
: "memory");
#endif
}
static __inline u_int32_t atomic_readandclear_32(volatile u_int32_t *addr)
{
u_int32_t result,temp;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"wmb\n" /* ensure pending writes have drained */
"1:\tldl_l %0,%3\n\t" /* load current value, asserting lock */
"ldiq %1,0\n\t" /* value to store */
"stl_c %1,%2\n\t" /* attempt to store */
"beq %1,1b\n" /* if the store failed, spin */
: "=&r"(result), "=&r"(temp), "=m" (*addr)
: "m" (*addr)
: "memory");
#endif
return result;
}
static __inline void atomic_set_64(volatile u_int64_t *p, u_int64_t v)
{
u_int64_t temp;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"1:\tldq_l %0, %3\n\t" /* load old value */
"bis %0, %2, %0\n\t" /* calculate new value */
"stq_c %0, %1\n\t" /* attempt to store */
"beq %0, 1b\n" /* spin if failed */
: "=&r" (temp), "=m" (*p)
: "r" (v), "m" (*p)
: "memory");
#endif
}
static __inline void atomic_clear_64(volatile u_int64_t *p, u_int64_t v)
{
u_int64_t temp;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"1:\tldq_l %0, %3\n\t" /* load old value */
"bic %0, %2, %0\n\t" /* calculate new value */
"stq_c %0, %1\n\t" /* attempt to store */
"beq %0, 1b\n" /* spin if failed */
: "=&r" (temp), "=m" (*p)
: "r" (v), "m" (*p)
: "memory");
#endif
}
static __inline void atomic_add_64(volatile u_int64_t *p, u_int64_t v)
{
u_int64_t temp;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"1:\tldq_l %0, %3\n\t" /* load old value */
"addq %0, %2, %0\n\t" /* calculate new value */
"stq_c %0, %1\n\t" /* attempt to store */
"beq %0, 1b\n" /* spin if failed */
: "=&r" (temp), "=m" (*p)
: "r" (v), "m" (*p)
: "memory");
#endif
}
static __inline void atomic_subtract_64(volatile u_int64_t *p, u_int64_t v)
{
u_int64_t temp;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"1:\tldq_l %0, %3\n\t" /* load old value */
"subq %0, %2, %0\n\t" /* calculate new value */
"stq_c %0, %1\n\t" /* attempt to store */
"beq %0, 1b\n" /* spin if failed */
: "=&r" (temp), "=m" (*p)
: "r" (v), "m" (*p)
: "memory");
#endif
}
static __inline u_int64_t atomic_readandclear_64(volatile u_int64_t *addr)
{
u_int64_t result,temp;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"wmb\n" /* ensure pending writes have drained */
"1:\tldq_l %0,%3\n\t" /* load current value, asserting lock */
"ldiq %1,0\n\t" /* value to store */
"stq_c %1,%2\n\t" /* attempt to store */
"beq %1,1b\n" /* if the store failed, spin */
: "=&r"(result), "=&r"(temp), "=m" (*addr)
: "m" (*addr)
: "memory");
#endif
return result;
}
#define ATOMIC_ACQ_REL(NAME, WIDTH) \
static __inline void \
atomic_##NAME##_acq_##WIDTH(volatile u_int##WIDTH##_t *p, u_int##WIDTH##_t v)\
{ \
atomic_##NAME##_##WIDTH(p, v); \
alpha_mb(); \
} \
\
static __inline void \
atomic_##NAME##_rel_##WIDTH(volatile u_int##WIDTH##_t *p, u_int##WIDTH##_t v)\
{ \
alpha_mb(); \
atomic_##NAME##_##WIDTH(p, v); \
}
/* Variants of simple arithmetic with memory barriers. */
ATOMIC_ACQ_REL(set, 8)
ATOMIC_ACQ_REL(clear, 8)
ATOMIC_ACQ_REL(add, 8)
ATOMIC_ACQ_REL(subtract, 8)
ATOMIC_ACQ_REL(set, 16)
ATOMIC_ACQ_REL(clear, 16)
ATOMIC_ACQ_REL(add, 16)
ATOMIC_ACQ_REL(subtract, 16)
ATOMIC_ACQ_REL(set, 32)
ATOMIC_ACQ_REL(clear, 32)
ATOMIC_ACQ_REL(add, 32)
ATOMIC_ACQ_REL(subtract, 32)
ATOMIC_ACQ_REL(set, 64)
ATOMIC_ACQ_REL(clear, 64)
ATOMIC_ACQ_REL(add, 64)
ATOMIC_ACQ_REL(subtract, 64)
#undef ATOMIC_ACQ_REL
/*
* We assume that a = b will do atomic loads and stores.
*/
#define ATOMIC_STORE_LOAD(WIDTH) \
static __inline u_int##WIDTH##_t \
atomic_load_acq_##WIDTH(volatile u_int##WIDTH##_t *p) \
{ \
u_int##WIDTH##_t v; \
\
v = *p; \
alpha_mb(); \
return (v); \
} \
\
static __inline void \
atomic_store_rel_##WIDTH(volatile u_int##WIDTH##_t *p, u_int##WIDTH##_t v)\
{ \
alpha_mb(); \
*p = v; \
}
ATOMIC_STORE_LOAD(32)
ATOMIC_STORE_LOAD(64)
#undef ATOMIC_STORE_LOAD
/*
* Atomically compare the value stored at *p with cmpval and if the
* two values are equal, update the value of *p with newval. Returns
* zero if the compare failed, nonzero otherwise.
*/
static __inline u_int32_t
atomic_cmpset_32(volatile u_int32_t* p, u_int32_t cmpval, u_int32_t newval)
{
u_int32_t ret;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"1:\tldl_l %0, %4\n\t" /* load old value */
"cmpeq %0, %2, %0\n\t" /* compare */
"beq %0, 2f\n\t" /* exit if not equal */
"mov %3, %0\n\t" /* value to store */
"stl_c %0, %1\n\t" /* attempt to store */
"beq %0, 1b\n\t" /* if it failed, spin */
"2:\n"
: "=&r" (ret), "=m" (*p)
: "r" ((long)(int)cmpval), "r" (newval), "m" (*p)
: "memory");
#endif
return ret;
}
/*
* Atomically compare the value stored at *p with cmpval and if the
* two values are equal, update the value of *p with newval. Returns
* zero if the compare failed, nonzero otherwise.
*/
static __inline u_int64_t
atomic_cmpset_64(volatile u_int64_t* p, u_int64_t cmpval, u_int64_t newval)
{
u_int64_t ret;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"1:\tldq_l %0, %4\n\t" /* load old value */
"cmpeq %0, %2, %0\n\t" /* compare */
"beq %0, 2f\n\t" /* exit if not equal */
"mov %3, %0\n\t" /* value to store */
"stq_c %0, %1\n\t" /* attempt to store */
"beq %0, 1b\n\t" /* if it failed, spin */
"2:\n"
: "=&r" (ret), "=m" (*p)
: "r" (cmpval), "r" (newval), "m" (*p)
: "memory");
#endif
return ret;
}
static __inline u_int32_t
atomic_cmpset_acq_32(volatile u_int32_t *p, u_int32_t cmpval, u_int32_t newval)
{
int retval;
retval = atomic_cmpset_32(p, cmpval, newval);
alpha_mb();
return (retval);
}
static __inline u_int32_t
atomic_cmpset_rel_32(volatile u_int32_t *p, u_int32_t cmpval, u_int32_t newval)
{
alpha_mb();
return (atomic_cmpset_32(p, cmpval, newval));
}
static __inline u_int64_t
atomic_cmpset_acq_64(volatile u_int64_t *p, u_int64_t cmpval, u_int64_t newval)
{
int retval;
retval = atomic_cmpset_64(p, cmpval, newval);
alpha_mb();
return (retval);
}
static __inline u_int64_t
atomic_cmpset_rel_64(volatile u_int64_t *p, u_int64_t cmpval, u_int64_t newval)
{
alpha_mb();
return (atomic_cmpset_64(p, cmpval, newval));
}
/*
* Atomically add the value of v to the integer pointed to by p and return
* the previous value of *p.
*/
static __inline u_int
atomic_fetchadd_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t value, temp;
#ifdef __GNUCLIKE_ASM
__asm __volatile (
"1:\tldl_l %0, %1\n\t" /* load old value */
"addl %0, %3, %2\n\t" /* calculate new value */
"stl_c %2, %1\n\t" /* attempt to store */
"beq %2, 1b\n" /* spin if failed */
: "=&r" (value), "=m" (*p), "=r" (temp)
: "r" (v), "m" (*p));
#endif
return (value);
}
/* Operations on chars. */
#define atomic_set_char atomic_set_8
#define atomic_set_acq_char atomic_set_acq_8
#define atomic_set_rel_char atomic_set_rel_8
#define atomic_clear_char atomic_clear_8
#define atomic_clear_acq_char atomic_clear_acq_8
#define atomic_clear_rel_char atomic_clear_rel_8
#define atomic_add_char atomic_add_8
#define atomic_add_acq_char atomic_add_acq_8
#define atomic_add_rel_char atomic_add_rel_8
#define atomic_subtract_char atomic_subtract_8
#define atomic_subtract_acq_char atomic_subtract_acq_8
#define atomic_subtract_rel_char atomic_subtract_rel_8
/* Operations on shorts. */
#define atomic_set_short atomic_set_16
#define atomic_set_acq_short atomic_set_acq_16
#define atomic_set_rel_short atomic_set_rel_16
#define atomic_clear_short atomic_clear_16
#define atomic_clear_acq_short atomic_clear_acq_16
#define atomic_clear_rel_short atomic_clear_rel_16
#define atomic_add_short atomic_add_16
#define atomic_add_acq_short atomic_add_acq_16
#define atomic_add_rel_short atomic_add_rel_16
#define atomic_subtract_short atomic_subtract_16
#define atomic_subtract_acq_short atomic_subtract_acq_16
#define atomic_subtract_rel_short atomic_subtract_rel_16
/* Operations on ints. */
#define atomic_set_int atomic_set_32
#define atomic_set_acq_int atomic_set_acq_32
#define atomic_set_rel_int atomic_set_rel_32
#define atomic_clear_int atomic_clear_32
#define atomic_clear_acq_int atomic_clear_acq_32
#define atomic_clear_rel_int atomic_clear_rel_32
#define atomic_add_int atomic_add_32
#define atomic_add_acq_int atomic_add_acq_32
#define atomic_add_rel_int atomic_add_rel_32
#define atomic_subtract_int atomic_subtract_32
#define atomic_subtract_acq_int atomic_subtract_acq_32
#define atomic_subtract_rel_int atomic_subtract_rel_32
#define atomic_cmpset_int atomic_cmpset_32
#define atomic_cmpset_acq_int atomic_cmpset_acq_32
#define atomic_cmpset_rel_int atomic_cmpset_rel_32
#define atomic_load_acq_int atomic_load_acq_32
#define atomic_store_rel_int atomic_store_rel_32
#define atomic_readandclear_int atomic_readandclear_32
#define atomic_fetchadd_int atomic_fetchadd_32
/* Operations on longs. */
#define atomic_set_long atomic_set_64
#define atomic_set_acq_long atomic_set_acq_64
#define atomic_set_rel_long atomic_set_rel_64
#define atomic_clear_long atomic_clear_64
#define atomic_clear_acq_long atomic_clear_acq_64
#define atomic_clear_rel_long atomic_clear_rel_64
#define atomic_add_long atomic_add_64
#define atomic_add_acq_long atomic_add_acq_64
#define atomic_add_rel_long atomic_add_rel_64
#define atomic_subtract_long atomic_subtract_64
#define atomic_subtract_acq_long atomic_subtract_acq_64
#define atomic_subtract_rel_long atomic_subtract_rel_64
#define atomic_cmpset_long atomic_cmpset_64
#define atomic_cmpset_acq_long atomic_cmpset_acq_64
#define atomic_cmpset_rel_long atomic_cmpset_rel_64
#define atomic_load_acq_long atomic_load_acq_64
#define atomic_store_rel_long atomic_store_rel_64
#define atomic_readandclear_long atomic_readandclear_64
/* Operations on pointers. */
#define atomic_set_ptr atomic_set_64
#define atomic_set_acq_ptr atomic_set_acq_64
#define atomic_set_rel_ptr atomic_set_rel_64
#define atomic_clear_ptr atomic_clear_64
#define atomic_clear_acq_ptr atomic_clear_acq_64
#define atomic_clear_rel_ptr atomic_clear_rel_64
#define atomic_add_ptr atomic_add_64
#define atomic_add_acq_ptr atomic_add_acq_64
#define atomic_add_rel_ptr atomic_add_rel_64
#define atomic_subtract_ptr atomic_subtract_64
#define atomic_subtract_acq_ptr atomic_subtract_acq_64
#define atomic_subtract_rel_ptr atomic_subtract_rel_64
#define atomic_cmpset_ptr atomic_cmpset_64
#define atomic_cmpset_acq_ptr atomic_cmpset_acq_64
#define atomic_cmpset_rel_ptr atomic_cmpset_rel_64
#define atomic_load_acq_ptr atomic_load_acq_64
#define atomic_store_rel_ptr atomic_store_rel_64
#define atomic_readandclear_ptr atomic_readandclear_64
#endif /* ! _MACHINE_ATOMIC_H_ */