freebsd-skq/sys/alpha/include/atomic.h
Marcel Moolenaar 19d4fb8e5c Workaround for compiling LINT. Large kernels (like LINT) can have
branch targets that are too far apart for the BRADDR relocation.
This is caused by the branch prediction optimizationi in the atomic
inlines here, because they jump across sections.
The workaround is to suppress jumping to a different section when
compiling LINT. To generate correct code in that case, the section
directives are replaced by a branch and a label to deal with the
fall-through case. Reasonably good C compilers will optimize this
away anyway, so the end result isn't really that bad.
2003-02-23 06:34:21 +00:00

536 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>
/*
* Quick and dirty workaround for compiling LINT. The kernel is too
* large to jump between sections without linker stubs/trampolines.
*/
#ifdef COMPILING_LINT
#define __COLD_SECTION "br 3f\n"
#define __HOT_SECTION "3:\n"
#else
#define __COLD_SECTION ".section .text3,\"ax\"\n"
#define __HOT_SECTION ".previous\n"
#endif
/*
* 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 */
__COLD_SECTION /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
__HOT_SECTION
: "=&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 */
__COLD_SECTION /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
__HOT_SECTION
: "=&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 */
__COLD_SECTION /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
__HOT_SECTION
: "=&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 */
__COLD_SECTION /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
__HOT_SECTION
: "=&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 */
__COLD_SECTION /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
__HOT_SECTION
: "=&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 */
__COLD_SECTION /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
__HOT_SECTION
: "=&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 */
__COLD_SECTION /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
__HOT_SECTION
: "=&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 */
__COLD_SECTION /* improve branch prediction */
"2:\tbr 1b\n" /* try again */
__HOT_SECTION
: "=&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 */
__COLD_SECTION /* improve branch prediction */
"3:\tbr 1b\n" /* try again */
__HOT_SECTION
: "=&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 */
__COLD_SECTION /* improve branch prediction */
"3:\tbr 1b\n" /* try again */
__HOT_SECTION
: "=&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_ */