89caa56972
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
442 lines
15 KiB
C
442 lines
15 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
|
|
|
|
/*
|
|
* Various simple arithmetic on memory which is atomic in the presence
|
|
* of interrupts and multiple processors.
|
|
*
|
|
* atomic_set_char(P, V) (*(u_char*)(P) |= (V))
|
|
* atomic_clear_char(P, V) (*(u_char*)(P) &= ~(V))
|
|
* atomic_add_char(P, V) (*(u_char*)(P) += (V))
|
|
* atomic_subtract_char(P, V) (*(u_char*)(P) -= (V))
|
|
*
|
|
* atomic_set_short(P, V) (*(u_short*)(P) |= (V))
|
|
* atomic_clear_short(P, V) (*(u_short*)(P) &= ~(V))
|
|
* atomic_add_short(P, V) (*(u_short*)(P) += (V))
|
|
* atomic_subtract_short(P, V) (*(u_short*)(P) -= (V))
|
|
*
|
|
* atomic_set_int(P, V) (*(u_int*)(P) |= (V))
|
|
* atomic_clear_int(P, V) (*(u_int*)(P) &= ~(V))
|
|
* atomic_add_int(P, V) (*(u_int*)(P) += (V))
|
|
* atomic_subtract_int(P, V) (*(u_int*)(P) -= (V))
|
|
* atomic_readandclear_int(P) (return *(u_int*)P; *(u_int*)P = 0;)
|
|
*
|
|
* atomic_set_long(P, V) (*(u_long*)(P) |= (V))
|
|
* atomic_clear_long(P, V) (*(u_long*)(P) &= ~(V))
|
|
* atomic_add_long(P, V) (*(u_long*)(P) += (V))
|
|
* atomic_subtract_long(P, V) (*(u_long*)(P) -= (V))
|
|
* atomic_readandclear_long(P) (return *(u_long*)P; *(u_long*)P = 0;)
|
|
*/
|
|
|
|
/*
|
|
* The above functions are expanded inline in the statically-linked
|
|
* kernel. Lock prefixes are generated if an SMP kernel is being
|
|
* built.
|
|
*
|
|
* Kernel modules call real functions which are built into the kernel.
|
|
* This allows kernel modules to be portable between UP and SMP systems.
|
|
*/
|
|
#if defined(KLD_MODULE) || !(defined(__GNUCLIKE_ASM) && defined(__CC_SUPPORTS___INLINE))
|
|
#define ATOMIC_ASM(NAME, TYPE, OP, CONS, V) \
|
|
void atomic_##NAME##_##TYPE(volatile u_##TYPE *p, u_##TYPE v)
|
|
|
|
int atomic_cmpset_int(volatile u_int *dst, u_int exp, u_int src);
|
|
int atomic_cmpset_long(volatile u_long *dst, u_long exp, u_long src);
|
|
u_int atomic_fetchadd_int(volatile u_int *p, u_int v);
|
|
|
|
#define ATOMIC_STORE_LOAD(TYPE, LOP, SOP) \
|
|
u_##TYPE atomic_load_acq_##TYPE(volatile u_##TYPE *p); \
|
|
void atomic_store_rel_##TYPE(volatile u_##TYPE *p, u_##TYPE v)
|
|
|
|
#else /* !KLD_MODULE && __GNUCLIKE_ASM && __CC_SUPPORTS___INLINE */
|
|
|
|
/*
|
|
* For userland, assume the SMP case and use lock prefixes so that
|
|
* the binaries will run on both types of systems.
|
|
*/
|
|
#if defined(SMP) || !defined(_KERNEL)
|
|
#define MPLOCKED lock ;
|
|
#else
|
|
#define MPLOCKED
|
|
#endif
|
|
|
|
/*
|
|
* The assembly is volatilized to demark potential before-and-after side
|
|
* effects if an interrupt or SMP collision were to occur.
|
|
*/
|
|
#define ATOMIC_ASM(NAME, TYPE, OP, CONS, V) \
|
|
static __inline void \
|
|
atomic_##NAME##_##TYPE(volatile u_##TYPE *p, u_##TYPE v)\
|
|
{ \
|
|
__asm __volatile(__XSTRING(MPLOCKED) OP \
|
|
: "=m" (*p) \
|
|
: CONS (V), "m" (*p)); \
|
|
} \
|
|
struct __hack
|
|
|
|
/*
|
|
* Atomic compare and set, used by the mutex functions
|
|
*
|
|
* if (*dst == exp) *dst = src (all 32 bit words)
|
|
*
|
|
* Returns 0 on failure, non-zero on success
|
|
*/
|
|
|
|
static __inline int
|
|
atomic_cmpset_int(volatile u_int *dst, u_int exp, u_int src)
|
|
{
|
|
int res = exp;
|
|
|
|
__asm __volatile (
|
|
" " __XSTRING(MPLOCKED) " "
|
|
" cmpxchgl %2,%1 ; "
|
|
" setz %%al ; "
|
|
" movzbl %%al,%0 ; "
|
|
"1: "
|
|
"# atomic_cmpset_int"
|
|
: "+a" (res), /* 0 (result) */
|
|
"=m" (*dst) /* 1 */
|
|
: "r" (src), /* 2 */
|
|
"m" (*dst) /* 3 */
|
|
: "memory");
|
|
|
|
return (res);
|
|
}
|
|
|
|
static __inline int
|
|
atomic_cmpset_long(volatile u_long *dst, u_long exp, u_long src)
|
|
{
|
|
long res = exp;
|
|
|
|
__asm __volatile (
|
|
" " __XSTRING(MPLOCKED) " "
|
|
" cmpxchgq %2,%1 ; "
|
|
" setz %%al ; "
|
|
" movzbq %%al,%0 ; "
|
|
"1: "
|
|
"# atomic_cmpset_long"
|
|
: "+a" (res), /* 0 (result) */
|
|
"=m" (*dst) /* 1 */
|
|
: "r" (src), /* 2 */
|
|
"m" (*dst) /* 3 */
|
|
: "memory");
|
|
|
|
return (res);
|
|
}
|
|
|
|
/*
|
|
* 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_int(volatile u_int *p, u_int v)
|
|
{
|
|
|
|
__asm __volatile (
|
|
" " __XSTRING(MPLOCKED) " "
|
|
" xaddl %0, %1 ; "
|
|
"# atomic_fetchadd_int"
|
|
: "+r" (v), /* 0 (result) */
|
|
"=m" (*p) /* 1 */
|
|
: "m" (*p)); /* 2 */
|
|
|
|
return (v);
|
|
}
|
|
|
|
#if defined(_KERNEL) && !defined(SMP)
|
|
|
|
/*
|
|
* We assume that a = b will do atomic loads and stores. However, on a
|
|
* PentiumPro or higher, reads may pass writes, so for that case we have
|
|
* to use a serializing instruction (i.e. with LOCK) to do the load in
|
|
* SMP kernels. For UP kernels, however, the cache of the single processor
|
|
* is always consistent, so we don't need any memory barriers.
|
|
*/
|
|
#define ATOMIC_STORE_LOAD(TYPE, LOP, SOP) \
|
|
static __inline u_##TYPE \
|
|
atomic_load_acq_##TYPE(volatile u_##TYPE *p) \
|
|
{ \
|
|
return (*p); \
|
|
} \
|
|
\
|
|
static __inline void \
|
|
atomic_store_rel_##TYPE(volatile u_##TYPE *p, u_##TYPE v)\
|
|
{ \
|
|
*p = v; \
|
|
} \
|
|
struct __hack
|
|
|
|
#else /* defined(SMP) */
|
|
|
|
#define ATOMIC_STORE_LOAD(TYPE, LOP, SOP) \
|
|
static __inline u_##TYPE \
|
|
atomic_load_acq_##TYPE(volatile u_##TYPE *p) \
|
|
{ \
|
|
u_##TYPE res; \
|
|
\
|
|
__asm __volatile(__XSTRING(MPLOCKED) LOP \
|
|
: "=a" (res), /* 0 (result) */\
|
|
"=m" (*p) /* 1 */ \
|
|
: "m" (*p) /* 2 */ \
|
|
: "memory"); \
|
|
\
|
|
return (res); \
|
|
} \
|
|
\
|
|
/* \
|
|
* The XCHG instruction asserts LOCK automagically. \
|
|
*/ \
|
|
static __inline void \
|
|
atomic_store_rel_##TYPE(volatile u_##TYPE *p, u_##TYPE v)\
|
|
{ \
|
|
__asm __volatile(SOP \
|
|
: "=m" (*p), /* 0 */ \
|
|
"+r" (v) /* 1 */ \
|
|
: "m" (*p)); /* 2 */ \
|
|
} \
|
|
struct __hack
|
|
|
|
#endif /* SMP */
|
|
|
|
#endif /* KLD_MODULE || !(__GNUCLIKE_ASM && __CC_SUPPORTS___INLINE) */
|
|
|
|
ATOMIC_ASM(set, char, "orb %b1,%0", "iq", v);
|
|
ATOMIC_ASM(clear, char, "andb %b1,%0", "iq", ~v);
|
|
ATOMIC_ASM(add, char, "addb %b1,%0", "iq", v);
|
|
ATOMIC_ASM(subtract, char, "subb %b1,%0", "iq", v);
|
|
|
|
ATOMIC_ASM(set, short, "orw %w1,%0", "ir", v);
|
|
ATOMIC_ASM(clear, short, "andw %w1,%0", "ir", ~v);
|
|
ATOMIC_ASM(add, short, "addw %w1,%0", "ir", v);
|
|
ATOMIC_ASM(subtract, short, "subw %w1,%0", "ir", v);
|
|
|
|
ATOMIC_ASM(set, int, "orl %1,%0", "ir", v);
|
|
ATOMIC_ASM(clear, int, "andl %1,%0", "ir", ~v);
|
|
ATOMIC_ASM(add, int, "addl %1,%0", "ir", v);
|
|
ATOMIC_ASM(subtract, int, "subl %1,%0", "ir", v);
|
|
|
|
ATOMIC_ASM(set, long, "orq %1,%0", "ir", v);
|
|
ATOMIC_ASM(clear, long, "andq %1,%0", "ir", ~v);
|
|
ATOMIC_ASM(add, long, "addq %1,%0", "ir", v);
|
|
ATOMIC_ASM(subtract, long, "subq %1,%0", "ir", v);
|
|
|
|
ATOMIC_STORE_LOAD(char, "cmpxchgb %b0,%1", "xchgb %b1,%0");
|
|
ATOMIC_STORE_LOAD(short,"cmpxchgw %w0,%1", "xchgw %w1,%0");
|
|
ATOMIC_STORE_LOAD(int, "cmpxchgl %0,%1", "xchgl %1,%0");
|
|
ATOMIC_STORE_LOAD(long, "cmpxchgq %0,%1", "xchgq %1,%0");
|
|
|
|
#undef ATOMIC_ASM
|
|
#undef ATOMIC_STORE_LOAD
|
|
|
|
#if !defined(WANT_FUNCTIONS)
|
|
|
|
/* Read the current value and store a zero in the destination. */
|
|
#if defined(__GNUCLIKE_ASM) && defined(__CC_SUPPORTS___INLINE)
|
|
|
|
static __inline u_int
|
|
atomic_readandclear_int(volatile u_int *addr)
|
|
{
|
|
u_int result;
|
|
|
|
result = 0;
|
|
__asm __volatile (
|
|
" xchgl %1,%0 ; "
|
|
"# atomic_readandclear_int"
|
|
: "+r" (result), /* 0 (result) */
|
|
"=m" (*addr) /* 1 (addr) */
|
|
: "m" (*addr));
|
|
|
|
return (result);
|
|
}
|
|
|
|
static __inline u_long
|
|
atomic_readandclear_long(volatile u_long *addr)
|
|
{
|
|
u_long result;
|
|
|
|
result = 0;
|
|
__asm __volatile (
|
|
" xchgq %1,%0 ; "
|
|
"# atomic_readandclear_long"
|
|
: "+r" (result), /* 0 (result) */
|
|
"=m" (*addr) /* 1 (addr) */
|
|
: "m" (*addr));
|
|
|
|
return (result);
|
|
}
|
|
|
|
#else /* !(__GNUCLIKE_ASM && __CC_SUPPORTS___INLINE) */
|
|
|
|
u_int atomic_readandclear_int(volatile u_int *);
|
|
u_long atomic_readandclear_long(volatile u_long *);
|
|
|
|
#endif /* __GNUCLIKE_ASM && __CC_SUPPORTS___INLINE */
|
|
|
|
/* Acquire and release variants are identical to the normal ones. */
|
|
#define atomic_set_acq_char atomic_set_char
|
|
#define atomic_set_rel_char atomic_set_char
|
|
#define atomic_clear_acq_char atomic_clear_char
|
|
#define atomic_clear_rel_char atomic_clear_char
|
|
#define atomic_add_acq_char atomic_add_char
|
|
#define atomic_add_rel_char atomic_add_char
|
|
#define atomic_subtract_acq_char atomic_subtract_char
|
|
#define atomic_subtract_rel_char atomic_subtract_char
|
|
|
|
#define atomic_set_acq_short atomic_set_short
|
|
#define atomic_set_rel_short atomic_set_short
|
|
#define atomic_clear_acq_short atomic_clear_short
|
|
#define atomic_clear_rel_short atomic_clear_short
|
|
#define atomic_add_acq_short atomic_add_short
|
|
#define atomic_add_rel_short atomic_add_short
|
|
#define atomic_subtract_acq_short atomic_subtract_short
|
|
#define atomic_subtract_rel_short atomic_subtract_short
|
|
|
|
#define atomic_set_acq_int atomic_set_int
|
|
#define atomic_set_rel_int atomic_set_int
|
|
#define atomic_clear_acq_int atomic_clear_int
|
|
#define atomic_clear_rel_int atomic_clear_int
|
|
#define atomic_add_acq_int atomic_add_int
|
|
#define atomic_add_rel_int atomic_add_int
|
|
#define atomic_subtract_acq_int atomic_subtract_int
|
|
#define atomic_subtract_rel_int atomic_subtract_int
|
|
#define atomic_cmpset_acq_int atomic_cmpset_int
|
|
#define atomic_cmpset_rel_int atomic_cmpset_int
|
|
|
|
#define atomic_set_acq_long atomic_set_long
|
|
#define atomic_set_rel_long atomic_set_long
|
|
#define atomic_clear_acq_long atomic_clear_long
|
|
#define atomic_clear_rel_long atomic_clear_long
|
|
#define atomic_add_acq_long atomic_add_long
|
|
#define atomic_add_rel_long atomic_add_long
|
|
#define atomic_subtract_acq_long atomic_subtract_long
|
|
#define atomic_subtract_rel_long atomic_subtract_long
|
|
#define atomic_cmpset_acq_long atomic_cmpset_long
|
|
#define atomic_cmpset_rel_long atomic_cmpset_long
|
|
|
|
/* Operations on 8-bit bytes. */
|
|
#define atomic_set_8 atomic_set_char
|
|
#define atomic_set_acq_8 atomic_set_acq_char
|
|
#define atomic_set_rel_8 atomic_set_rel_char
|
|
#define atomic_clear_8 atomic_clear_char
|
|
#define atomic_clear_acq_8 atomic_clear_acq_char
|
|
#define atomic_clear_rel_8 atomic_clear_rel_char
|
|
#define atomic_add_8 atomic_add_char
|
|
#define atomic_add_acq_8 atomic_add_acq_char
|
|
#define atomic_add_rel_8 atomic_add_rel_char
|
|
#define atomic_subtract_8 atomic_subtract_char
|
|
#define atomic_subtract_acq_8 atomic_subtract_acq_char
|
|
#define atomic_subtract_rel_8 atomic_subtract_rel_char
|
|
#define atomic_load_acq_8 atomic_load_acq_char
|
|
#define atomic_store_rel_8 atomic_store_rel_char
|
|
|
|
/* Operations on 16-bit words. */
|
|
#define atomic_set_16 atomic_set_short
|
|
#define atomic_set_acq_16 atomic_set_acq_short
|
|
#define atomic_set_rel_16 atomic_set_rel_short
|
|
#define atomic_clear_16 atomic_clear_short
|
|
#define atomic_clear_acq_16 atomic_clear_acq_short
|
|
#define atomic_clear_rel_16 atomic_clear_rel_short
|
|
#define atomic_add_16 atomic_add_short
|
|
#define atomic_add_acq_16 atomic_add_acq_short
|
|
#define atomic_add_rel_16 atomic_add_rel_short
|
|
#define atomic_subtract_16 atomic_subtract_short
|
|
#define atomic_subtract_acq_16 atomic_subtract_acq_short
|
|
#define atomic_subtract_rel_16 atomic_subtract_rel_short
|
|
#define atomic_load_acq_16 atomic_load_acq_short
|
|
#define atomic_store_rel_16 atomic_store_rel_short
|
|
|
|
/* Operations on 32-bit double words. */
|
|
#define atomic_set_32 atomic_set_int
|
|
#define atomic_set_acq_32 atomic_set_acq_int
|
|
#define atomic_set_rel_32 atomic_set_rel_int
|
|
#define atomic_clear_32 atomic_clear_int
|
|
#define atomic_clear_acq_32 atomic_clear_acq_int
|
|
#define atomic_clear_rel_32 atomic_clear_rel_int
|
|
#define atomic_add_32 atomic_add_int
|
|
#define atomic_add_acq_32 atomic_add_acq_int
|
|
#define atomic_add_rel_32 atomic_add_rel_int
|
|
#define atomic_subtract_32 atomic_subtract_int
|
|
#define atomic_subtract_acq_32 atomic_subtract_acq_int
|
|
#define atomic_subtract_rel_32 atomic_subtract_rel_int
|
|
#define atomic_load_acq_32 atomic_load_acq_int
|
|
#define atomic_store_rel_32 atomic_store_rel_int
|
|
#define atomic_cmpset_32 atomic_cmpset_int
|
|
#define atomic_cmpset_acq_32 atomic_cmpset_acq_int
|
|
#define atomic_cmpset_rel_32 atomic_cmpset_rel_int
|
|
#define atomic_readandclear_32 atomic_readandclear_int
|
|
#define atomic_fetchadd_32 atomic_fetchadd_int
|
|
|
|
/* Operations on 64-bit quad words. */
|
|
#define atomic_set_64 atomic_set_long
|
|
#define atomic_set_acq_64 atomic_set_acq_long
|
|
#define atomic_set_rel_64 atomic_set_rel_long
|
|
#define atomic_clear_64 atomic_clear_long
|
|
#define atomic_clear_acq_64 atomic_clear_acq_long
|
|
#define atomic_clear_rel_64 atomic_clear_rel_long
|
|
#define atomic_add_64 atomic_add_long
|
|
#define atomic_add_acq_64 atomic_add_acq_long
|
|
#define atomic_add_rel_64 atomic_add_rel_long
|
|
#define atomic_subtract_64 atomic_subtract_long
|
|
#define atomic_subtract_acq_64 atomic_subtract_acq_long
|
|
#define atomic_subtract_rel_64 atomic_subtract_rel_long
|
|
#define atomic_load_acq_64 atomic_load_acq_long
|
|
#define atomic_store_rel_64 atomic_store_rel_long
|
|
#define atomic_cmpset_64 atomic_cmpset_long
|
|
#define atomic_cmpset_acq_64 atomic_cmpset_acq_long
|
|
#define atomic_cmpset_rel_64 atomic_cmpset_rel_long
|
|
#define atomic_readandclear_64 atomic_readandclear_long
|
|
|
|
/* Operations on pointers. */
|
|
#define atomic_set_ptr atomic_set_long
|
|
#define atomic_set_acq_ptr atomic_set_acq_long
|
|
#define atomic_set_rel_ptr atomic_set_rel_long
|
|
#define atomic_clear_ptr atomic_clear_long
|
|
#define atomic_clear_acq_ptr atomic_clear_acq_long
|
|
#define atomic_clear_rel_ptr atomic_clear_rel_long
|
|
#define atomic_add_ptr atomic_add_long
|
|
#define atomic_add_acq_ptr atomic_add_acq_long
|
|
#define atomic_add_rel_ptr atomic_add_rel_long
|
|
#define atomic_subtract_ptr atomic_subtract_long
|
|
#define atomic_subtract_acq_ptr atomic_subtract_acq_long
|
|
#define atomic_subtract_rel_ptr atomic_subtract_rel_long
|
|
#define atomic_load_acq_ptr atomic_load_acq_long
|
|
#define atomic_store_rel_ptr atomic_store_rel_long
|
|
#define atomic_cmpset_ptr atomic_cmpset_long
|
|
#define atomic_cmpset_acq_ptr atomic_cmpset_acq_long
|
|
#define atomic_cmpset_rel_ptr atomic_cmpset_rel_long
|
|
#define atomic_readandclear_ptr atomic_readandclear_long
|
|
|
|
#endif /* !defined(WANT_FUNCTIONS) */
|
|
#endif /* ! _MACHINE_ATOMIC_H_ */
|