freebsd-skq/sys/alpha/include/atomic.h
Andrew Gallatin 7a966f2ded Remove extranious memory barriers, and correct the placement of a few others.
This provides a 30% reduction in system time and a 6% reduction in wallclock time
for a make buildworld on my xp1000 (one 21264).

FWIW, I've been running this for nearly 2 months without problems.

Portions submitted by: ticso, jhb
Tested by: jhb (ds20 dual 21264)
2002-10-30 01:41:44 +00:00

524 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_
#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 __GNUC__
__asm __volatile (
"1:\tldl_l %0, %2\n\t" /* load old value */
"bis %0, %3, %0\n\t" /* calculate new value */
"stl_c %0, %1\n\t" /* attempt to store */
"beq %0, 2f\n\t" /* spin if failed */
".section .text3,\"ax\"\n" /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
".previous\n"
: "=&r" (temp), "=m" (*p)
: "m" (*p), "r" (v)
: "memory");
#endif
}
static __inline void atomic_clear_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t temp;
#ifdef __GNUC__
__asm __volatile (
"1:\tldl_l %0, %1\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, 2f\n\t" /* spin if failed */
".section .text3,\"ax\"\n" /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
".previous\n"
: "=&r" (temp), "+m" (*p)
: "r" (v)
: "memory");
#endif
}
static __inline void atomic_add_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t temp;
#ifdef __GNUC__
__asm __volatile (
"1:\tldl_l %0, %1\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, 2f\n\t" /* spin if failed */
".section .text3,\"ax\"\n" /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
".previous\n"
: "=&r" (temp), "+m" (*p)
: "r" (v)
: "memory");
#endif
}
static __inline void atomic_subtract_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t temp;
#ifdef __GNUC__
__asm __volatile (
"1:\tldl_l %0, %1\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, 2f\n\t" /* spin if failed */
".section .text3,\"ax\"\n" /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
".previous\n"
: "=&r" (temp), "+m" (*p)
: "r" (v)
: "memory");
#endif
}
static __inline u_int32_t atomic_readandclear_32(volatile u_int32_t *addr)
{
u_int32_t result,temp;
#ifdef __GNUC__
__asm __volatile (
"wmb\n" /* ensure pending writes have drained */
"1:\tldl_l %0,%2\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 %1,2f\n\t" /* if the store failed, spin */
"br 3f\n" /* it worked, exit */
"2:\tbr 1b\n" /* *addr not updated, loop */
"3:\n" /* it worked */
: "=&r"(result), "=&r"(temp), "+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 __GNUC__
__asm __volatile (
"1:\tldq_l %0, %1\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, 2f\n\t" /* spin if failed */
".section .text3,\"ax\"\n" /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
".previous\n"
: "=&r" (temp), "+m" (*p)
: "r" (v)
: "memory");
#endif
}
static __inline void atomic_clear_64(volatile u_int64_t *p, u_int64_t v)
{
u_int64_t temp;
#ifdef __GNUC__
__asm __volatile (
"1:\tldq_l %0, %1\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, 2f\n\t" /* spin if failed */
".section .text3,\"ax\"\n" /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
".previous\n"
: "=&r" (temp), "+m" (*p)
: "r" (v)
: "memory");
#endif
}
static __inline void atomic_add_64(volatile u_int64_t *p, u_int64_t v)
{
u_int64_t temp;
#ifdef __GNUC__
__asm __volatile (
"1:\tldq_l %0, %1\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, 2f\n\t" /* spin if failed */
".section .text3,\"ax\"\n" /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
".previous\n"
: "=&r" (temp), "+m" (*p)
: "r" (v)
: "memory");
#endif
}
static __inline void atomic_subtract_64(volatile u_int64_t *p, u_int64_t v)
{
u_int64_t temp;
#ifdef __GNUC__
__asm __volatile (
"1:\tldq_l %0, %1\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, 2f\n\t" /* spin if failed */
".section .text3,\"ax\"\n" /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
".previous\n"
: "=&r" (temp), "+m" (*p)
: "r" (v)
: "memory");
#endif
}
static __inline u_int64_t atomic_readandclear_64(volatile u_int64_t *addr)
{
u_int64_t result,temp;
#ifdef __GNUC__
__asm __volatile (
"wmb\n" /* ensure pending writes have drained */
"1:\tldq_l %0,%2\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 %1,2f\n\t" /* if the store failed, spin */
"br 3f\n" /* it worked, exit */
"2:\tbr 1b\n" /* *addr not updated, loop */
"3:\n" /* it worked */
: "=&r"(result), "=&r"(temp), "+m" (*addr)
:
: "memory");
#endif
return result;
}
#define atomic_set_char atomic_set_8
#define atomic_clear_char atomic_clear_8
#define atomic_add_char atomic_add_8
#define atomic_subtract_char atomic_subtract_8
#define atomic_set_short atomic_set_16
#define atomic_clear_short atomic_clear_16
#define atomic_add_short atomic_add_16
#define atomic_subtract_short atomic_subtract_16
#define atomic_set_int atomic_set_32
#define atomic_clear_int atomic_clear_32
#define atomic_add_int atomic_add_32
#define atomic_subtract_int atomic_subtract_32
#define atomic_readandclear_int atomic_readandclear_32
#define atomic_set_long atomic_set_64
#define atomic_clear_long atomic_clear_64
#define atomic_add_long atomic_add_64
#define atomic_subtract_long atomic_subtract_64
#define atomic_readandclear_long atomic_readandclear_64
#define ATOMIC_ACQ_REL(NAME, WIDTH, TYPE) \
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); \
} \
\
static __inline void \
atomic_##NAME##_acq_##TYPE(volatile u_int##WIDTH##_t *p, u_int##WIDTH##_t v)\
{ \
atomic_##NAME##_##WIDTH(p, v); \
alpha_mb(); \
} \
\
static __inline void \
atomic_##NAME##_rel_##TYPE(volatile u_int##WIDTH##_t *p, u_int##WIDTH##_t v)\
{ \
alpha_mb(); \
atomic_##NAME##_##WIDTH(p, v); \
}
ATOMIC_ACQ_REL(set, 8, char)
ATOMIC_ACQ_REL(clear, 8, char)
ATOMIC_ACQ_REL(add, 8, char)
ATOMIC_ACQ_REL(subtract, 8, char)
ATOMIC_ACQ_REL(set, 16, short)
ATOMIC_ACQ_REL(clear, 16, short)
ATOMIC_ACQ_REL(add, 16, short)
ATOMIC_ACQ_REL(subtract, 16, short)
ATOMIC_ACQ_REL(set, 32, int)
ATOMIC_ACQ_REL(clear, 32, int)
ATOMIC_ACQ_REL(add, 32, int)
ATOMIC_ACQ_REL(subtract, 32, int)
ATOMIC_ACQ_REL(set, 64, long)
ATOMIC_ACQ_REL(clear, 64, long)
ATOMIC_ACQ_REL(add, 64, long)
ATOMIC_ACQ_REL(subtract, 64, long)
#undef ATOMIC_ACQ_REL
/*
* We assume that a = b will do atomic loads and stores.
*/
#define ATOMIC_STORE_LOAD(TYPE, WIDTH) \
static __inline u_##TYPE \
atomic_load_acq_##WIDTH(volatile u_##TYPE *p) \
{ \
u_##TYPE v; \
\
v = *p; \
alpha_mb(); \
return (v); \
} \
\
static __inline void \
atomic_store_rel_##WIDTH(volatile u_##TYPE *p, u_##TYPE v)\
{ \
alpha_mb(); \
*p = v; \
} \
static __inline u_##TYPE \
atomic_load_acq_##TYPE(volatile u_##TYPE *p) \
{ \
u_##TYPE v; \
\
v = *p; \
alpha_mb(); \
return (v); \
} \
\
static __inline void \
atomic_store_rel_##TYPE(volatile u_##TYPE *p, u_##TYPE v)\
{ \
alpha_mb(); \
*p = v; \
}
ATOMIC_STORE_LOAD(char, 8)
ATOMIC_STORE_LOAD(short, 16)
ATOMIC_STORE_LOAD(int, 32)
ATOMIC_STORE_LOAD(long, 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 __GNUC__
__asm __volatile (
"1:\tldl_l %0, %1\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, 3f\n\t" /* if it failed, spin */
"2:\n" /* done */
".section .text3,\"ax\"\n" /* improve branch prediction */
"3:\tbr 1b\n" /* try again */
".previous\n"
: "=&r" (ret), "+m" (*p)
: "r" ((long)(int)cmpval), "r" (newval)
: "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 __GNUC__
__asm __volatile (
"1:\tldq_l %0, %1\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, 3f\n\t" /* if it failed, spin */
"2:\n" /* done */
".section .text3,\"ax\"\n" /* improve branch prediction */
"3:\tbr 1b\n" /* try again */
".previous\n"
: "=&r" (ret), "+m" (*p)
: "r" (cmpval), "r" (newval)
: "memory");
#endif
return ret;
}
#define atomic_cmpset_int atomic_cmpset_32
#define atomic_cmpset_long atomic_cmpset_64
static __inline int
atomic_cmpset_ptr(volatile void *dst, void *exp, void *src)
{
return (atomic_cmpset_long((volatile u_long *)dst, (u_long)exp,
(u_long)src));
}
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));
}
#define atomic_cmpset_acq_int atomic_cmpset_acq_32
#define atomic_cmpset_rel_int atomic_cmpset_rel_32
#define atomic_cmpset_acq_long atomic_cmpset_acq_64
#define atomic_cmpset_rel_long atomic_cmpset_rel_64
static __inline int
atomic_cmpset_acq_ptr(volatile void *dst, void *exp, void *src)
{
return (atomic_cmpset_acq_long((volatile u_long *)dst, (u_long)exp,
(u_long)src));
}
static __inline int
atomic_cmpset_rel_ptr(volatile void *dst, void *exp, void *src)
{
return (atomic_cmpset_rel_long((volatile u_long *)dst, (u_long)exp,
(u_long)src));
}
static __inline void *
atomic_load_acq_ptr(volatile void *p)
{
return (void *)atomic_load_acq_long((volatile u_long *)p);
}
static __inline void
atomic_store_rel_ptr(volatile void *p, void *v)
{
atomic_store_rel_long((volatile u_long *)p, (u_long)v);
}
#define ATOMIC_PTR(NAME) \
static __inline void \
atomic_##NAME##_ptr(volatile void *p, uintptr_t v) \
{ \
atomic_##NAME##_long((volatile u_long *)p, v); \
} \
\
static __inline void \
atomic_##NAME##_acq_ptr(volatile void *p, uintptr_t v) \
{ \
atomic_##NAME##_acq_long((volatile u_long *)p, v);\
} \
\
static __inline void \
atomic_##NAME##_rel_ptr(volatile void *p, uintptr_t v) \
{ \
atomic_##NAME##_rel_long((volatile u_long *)p, v);\
}
ATOMIC_PTR(set)
ATOMIC_PTR(clear)
ATOMIC_PTR(add)
ATOMIC_PTR(subtract)
#undef ATOMIC_PTR
#endif /* ! _MACHINE_ATOMIC_H_ */