| /*- |
| * 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 _BSD_MACHINE_ATOMIC_H_ |
| #define _BSD_MACHINE_ATOMIC_H_ |
| |
| #ifndef _BSD_SYS_CDEFS_H_ |
| #error this file needs sys/cdefs.h as a prerequisite |
| #endif |
| |
| #define mb() __asm __volatile("mfence;" : : : "memory") |
| #define wmb() __asm __volatile("sfence;" : : : "memory") |
| #define rmb() __asm __volatile("lfence;" : : : "memory") |
| |
| /* |
| * Various simple operations on memory, each of 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) |
| #define ATOMIC_ASM(NAME, TYPE, OP, CONS, V) \ |
| void atomic_##NAME##_##TYPE(volatile u_##TYPE *p, u_##TYPE v); \ |
| void atomic_##NAME##_barr_##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); |
| u_long atomic_fetchadd_long(volatile u_long *p, u_long 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 */ |
| |
| /* |
| * For userland, always use lock prefixes so that the binaries will run |
| * on both SMP and !SMP systems. |
| */ |
| #if defined(SMP) || !defined(_FREEBSD_KERNEL) |
| #define MPLOCKED "lock ; " |
| #else |
| #define MPLOCKED |
| #endif |
| |
| /* |
| * The assembly is volatilized to avoid code chunk removal by the compiler. |
| * GCC aggressively reorders operations and memory clobbering is necessary |
| * in order to avoid that for memory barriers. |
| */ |
| #define ATOMIC_ASM(NAME, TYPE, OP, CONS, V) \ |
| static __inline void \ |
| atomic_##NAME##_##TYPE(volatile u_##TYPE *p, u_##TYPE v)\ |
| { \ |
| __asm __volatile(MPLOCKED OP \ |
| : "=m" (*p) \ |
| : CONS (V), "m" (*p)); \ |
| } \ |
| \ |
| static __inline void \ |
| atomic_##NAME##_barr_##TYPE(volatile u_##TYPE *p, u_##TYPE v)\ |
| { \ |
| __asm __volatile(MPLOCKED OP \ |
| : "=m" (*p) \ |
| : CONS (V), "m" (*p) \ |
| : "memory"); \ |
| } \ |
| 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) |
| { |
| u_char res; |
| |
| __asm __volatile( |
| " " MPLOCKED " " |
| " cmpxchgl %2,%1 ; " |
| " sete %0 ; " |
| "1: " |
| "# atomic_cmpset_int" |
| : "=a" (res), /* 0 */ |
| "=m" (*dst) /* 1 */ |
| : "r" (src), /* 2 */ |
| "a" (exp), /* 3 */ |
| "m" (*dst) /* 4 */ |
| : "memory"); |
| |
| return (res); |
| } |
| |
| static __inline int |
| atomic_cmpset_long(volatile u_long *dst, u_long exp, u_long src) |
| { |
| u_char res; |
| |
| __asm __volatile( |
| " " MPLOCKED " " |
| " cmpxchgq %2,%1 ; " |
| " sete %0 ; " |
| "1: " |
| "# atomic_cmpset_long" |
| : "=a" (res), /* 0 */ |
| "=m" (*dst) /* 1 */ |
| : "r" (src), /* 2 */ |
| "a" (exp), /* 3 */ |
| "m" (*dst) /* 4 */ |
| : "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( |
| " " MPLOCKED " " |
| " xaddl %0, %1 ; " |
| "# atomic_fetchadd_int" |
| : "+r" (v), /* 0 (result) */ |
| "=m" (*p) /* 1 */ |
| : "m" (*p)); /* 2 */ |
| |
| return (v); |
| } |
| |
| /* |
| * Atomically add the value of v to the long integer pointed to by p and return |
| * the previous value of *p. |
| */ |
| static __inline u_long |
| atomic_fetchadd_long(volatile u_long *p, u_long v) |
| { |
| |
| __asm __volatile( |
| " " MPLOCKED " " |
| " xaddq %0, %1 ; " |
| "# atomic_fetchadd_long" |
| : "+r" (v), /* 0 (result) */ |
| "=m" (*p) /* 1 */ |
| : "m" (*p)); /* 2 */ |
| |
| return (v); |
| } |
| |
| #if defined(_FREEBSD_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 only need to take care of compiler. |
| */ |
| #define ATOMIC_STORE_LOAD(TYPE, LOP, SOP) \ |
| static __inline u_##TYPE \ |
| atomic_load_acq_##TYPE(volatile u_##TYPE *p) \ |
| { \ |
| u_##TYPE tmp; \ |
| \ |
| tmp = *p; \ |
| __asm __volatile ("" : : : "memory"); \ |
| return (tmp); \ |
| } \ |
| \ |
| static __inline void \ |
| atomic_store_rel_##TYPE(volatile u_##TYPE *p, u_##TYPE v)\ |
| { \ |
| __asm __volatile ("" : : : "memory"); \ |
| *p = v; \ |
| } \ |
| struct __hack |
| |
| #else /* !(_FREEBSD_KERNEL && !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(MPLOCKED LOP \ |
| : "=a" (res), /* 0 */ \ |
| "=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 */ \ |
| : "memory"); \ |
| } \ |
| struct __hack |
| |
| #endif /* _FREEBSD_KERNEL && !SMP */ |
| |
| #endif /* KLD_MODULE || !__GNUCLIKE_ASM */ |
| |
| 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 |
| |
| #ifndef WANT_FUNCTIONS |
| |
| /* Read the current value and store a zero in the destination. */ |
| #ifdef __GNUCLIKE_ASM |
| |
| static __inline u_int |
| atomic_readandclear_int(volatile u_int *addr) |
| { |
| u_int res; |
| |
| res = 0; |
| __asm __volatile( |
| " xchgl %1,%0 ; " |
| "# atomic_readandclear_int" |
| : "+r" (res), /* 0 */ |
| "=m" (*addr) /* 1 */ |
| : "m" (*addr)); |
| |
| return (res); |
| } |
| |
| static __inline u_long |
| atomic_readandclear_long(volatile u_long *addr) |
| { |
| u_long res; |
| |
| res = 0; |
| __asm __volatile( |
| " xchgq %1,%0 ; " |
| "# atomic_readandclear_long" |
| : "+r" (res), /* 0 */ |
| "=m" (*addr) /* 1 */ |
| : "m" (*addr)); |
| |
| return (res); |
| } |
| |
| #else /* !__GNUCLIKE_ASM */ |
| |
| u_int atomic_readandclear_int(volatile u_int *addr); |
| u_long atomic_readandclear_long(volatile u_long *addr); |
| |
| #endif /* __GNUCLIKE_ASM */ |
| |
| #define atomic_set_acq_char atomic_set_barr_char |
| #define atomic_set_rel_char atomic_set_barr_char |
| #define atomic_clear_acq_char atomic_clear_barr_char |
| #define atomic_clear_rel_char atomic_clear_barr_char |
| #define atomic_add_acq_char atomic_add_barr_char |
| #define atomic_add_rel_char atomic_add_barr_char |
| #define atomic_subtract_acq_char atomic_subtract_barr_char |
| #define atomic_subtract_rel_char atomic_subtract_barr_char |
| |
| #define atomic_set_acq_short atomic_set_barr_short |
| #define atomic_set_rel_short atomic_set_barr_short |
| #define atomic_clear_acq_short atomic_clear_barr_short |
| #define atomic_clear_rel_short atomic_clear_barr_short |
| #define atomic_add_acq_short atomic_add_barr_short |
| #define atomic_add_rel_short atomic_add_barr_short |
| #define atomic_subtract_acq_short atomic_subtract_barr_short |
| #define atomic_subtract_rel_short atomic_subtract_barr_short |
| |
| #define atomic_set_acq_int atomic_set_barr_int |
| #define atomic_set_rel_int atomic_set_barr_int |
| #define atomic_clear_acq_int atomic_clear_barr_int |
| #define atomic_clear_rel_int atomic_clear_barr_int |
| #define atomic_add_acq_int atomic_add_barr_int |
| #define atomic_add_rel_int atomic_add_barr_int |
| #define atomic_subtract_acq_int atomic_subtract_barr_int |
| #define atomic_subtract_rel_int atomic_subtract_barr_int |
| #define atomic_cmpset_acq_int atomic_cmpset_int |
| #define atomic_cmpset_rel_int atomic_cmpset_int |
| |
| #define atomic_set_acq_long atomic_set_barr_long |
| #define atomic_set_rel_long atomic_set_barr_long |
| #define atomic_clear_acq_long atomic_clear_barr_long |
| #define atomic_clear_rel_long atomic_clear_barr_long |
| #define atomic_add_acq_long atomic_add_barr_long |
| #define atomic_add_rel_long atomic_add_barr_long |
| #define atomic_subtract_acq_long atomic_subtract_barr_long |
| #define atomic_subtract_rel_long atomic_subtract_barr_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 /* !WANT_FUNCTIONS */ |
| |
| #endif /* !_BSD_MACHINE_ATOMIC_H_ */ |
