freebsd-skq/sys/ia64/include/atomic.h
dfr f610b17c8d * Add rudimentary DDB support (no kgdb, no backtrace, no single step).
* Track recent changes to SWI code.
* Allocate RIDs for pmaps (untested).
* Implement assembler version of cpu_switch - its cleaner that way.
2000-10-10 14:57:10 +00:00

214 lines
6.0 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_
/*
* Various simple arithmetic on memory which is atomic in the presence
* of interrupts and SMP safe.
*/
/*
* Everything is built out of cmpxchg.
*/
#define IA64_CMPXCHG(sz, sem, type, p, cmpval, newval) \
({ \
type _cmpval = cmpval; \
type _newval = newval; \
volatile type *_p = (volatile type *) p; \
type _ret; \
\
__asm __volatile ( \
"mov ar.ccv=%2;;\n\t" \
"cmpxchg" #sz "." #sem " %0=%4,%3,ar.ccv\n\t" \
: "=r" (_ret), "=m" (*_p) \
: "r" (_cmpval), "r" (_newval), "m" (*_p) \
: "memory"); \
_ret; \
})
/*
* Some common forms of cmpxch.
*/
static __inline u_int32_t
ia64_cmpxchg_acq_32(volatile u_int32_t* p, u_int32_t cmpval, u_int32_t newval)
{
return IA64_CMPXCHG(4, acq, u_int32_t, p, cmpval, newval);
}
static __inline u_int32_t
ia64_cmpxchg_rel_32(volatile u_int32_t* p, u_int32_t cmpval, u_int32_t newval)
{
return IA64_CMPXCHG(4, rel, u_int32_t, p, cmpval, newval);
}
static __inline u_int64_t
ia64_cmpxchg_acq_64(volatile u_int64_t* p, u_int64_t cmpval, u_int64_t newval)
{
return IA64_CMPXCHG(8, acq, u_int64_t, p, cmpval, newval);
}
static __inline u_int64_t
ia64_cmpxchg_rel_64(volatile u_int64_t* p, u_int64_t cmpval, u_int64_t newval)
{
return IA64_CMPXCHG(8, rel, u_int64_t, p, cmpval, newval);
}
/*
* Store with release semantics is used to release locks.
*/
static __inline void
ia64_st_rel_32(volatile u_int32_t* p, u_int32_t v)
{
__asm __volatile ("st4.rel %0=%1"
: "=m" (*p)
: "r" (v)
: "memory");
}
static __inline void
ia64_st_rel_64(volatile u_int64_t* p, u_int64_t v)
{
__asm __volatile ("st8.rel %0=%1"
: "=m" (*p)
: "r" (v)
: "memory");
}
#define IA64_ATOMIC(sz, type, name, op) \
\
static __inline void \
atomic_##name(volatile type *p, type v) \
{ \
type old; \
do { \
old = *p; \
} while (IA64_CMPXCHG(sz, acq, type, p, old, old op v) != old); \
}
IA64_ATOMIC(1, u_int8_t, set_8, |)
IA64_ATOMIC(2, u_int16_t, set_16, |)
IA64_ATOMIC(4, u_int32_t, set_32, |)
IA64_ATOMIC(8, u_int64_t, set_64, |)
IA64_ATOMIC(1, u_int8_t, clear_8, &~)
IA64_ATOMIC(2, u_int16_t, clear_16, &~)
IA64_ATOMIC(4, u_int32_t, clear_32, &~)
IA64_ATOMIC(8, u_int64_t, clear_64, &~)
IA64_ATOMIC(1, u_int8_t, add_8, +)
IA64_ATOMIC(2, u_int16_t, add_16, +)
IA64_ATOMIC(4, u_int32_t, add_32, +)
IA64_ATOMIC(8, u_int64_t, add_64, +)
IA64_ATOMIC(1, u_int8_t, subtract_8, -)
IA64_ATOMIC(2, u_int16_t, subtract_16, -)
IA64_ATOMIC(4, u_int32_t, subtract_32, -)
IA64_ATOMIC(8, u_int64_t, subtract_64, -)
#undef IA64_ATOMIC
#undef IA64_CMPXCHG
#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_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
/*
* 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 int
atomic_cmpset_32(volatile u_int32_t* p, u_int32_t cmpval, u_int32_t newval)
{
return ia64_cmpxchg_acq_32(p, cmpval, newval) == cmpval;
}
/*
* 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 int
atomic_cmpset_64(volatile u_int64_t* p, u_int64_t cmpval, u_int64_t newval)
{
return ia64_cmpxchg_acq_64(p, cmpval, newval) == cmpval;
}
#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_readandclear_32(volatile u_int32_t* p)
{
u_int32_t val;
do {
val = *p;
} while (!atomic_cmpset_32(p, val, 0));
return val;
}
static __inline u_int64_t
atomic_readandclear_64(volatile u_int64_t* p)
{
u_int64_t val;
do {
val = *p;
} while (!atomic_cmpset_64(p, val, 0));
return val;
}
#define atomic_readandclear_int atomic_readandclear_32
#define atomic_readandclear_long atomic_readandclear_64
#endif /* ! _MACHINE_ATOMIC_H_ */