/* $NetBSD: atomic_init_testset.c,v 1.16 2019/02/18 11:22:56 martin Exp $ */
/*-
* Copyright (c) 2008 The NetBSD Foundation, Inc.
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* libc glue for atomic operations where the hardware does not provide
* compare-and-swap. It's assumed that this will only be used on 32-bit
* platforms.
*
* This should be compiled with '-fno-reorder-blocks -fomit-frame-pointer'
* if using gcc.
*/
#include <sys/cdefs.h>
__RCSID("$NetBSD: atomic_init_testset.c,v 1.16 2019/02/18 11:22:56 martin Exp $");
#include "atomic_op_namespace.h"
#include <sys/types.h>
#include <sys/atomic.h>
#include <sys/lock.h>
#include <sys/ras.h>
#include <sys/sysctl.h>
#include <string.h>
#define I2 __SIMPLELOCK_UNLOCKED, __SIMPLELOCK_UNLOCKED,
#define I16 I2 I2 I2 I2 I2 I2 I2 I2
#define I128 I16 I16 I16 I16 I16 I16 I16 I16
static __cpu_simple_lock_t atomic_locks[128] = { I128 };
/*
* Pick a lock out of above array depending on the object address
* passed. Most variables used atomically will not be in the same
* cacheline - and if they are, using the same lock is fine.
*/
#define HASH(PTR) (((uintptr_t)(PTR) >> 3) & 127)
#ifdef __HAVE_ASM_ATOMIC_CAS_UP
extern uint32_t _atomic_cas_up(volatile uint32_t *, uint32_t, uint32_t);
#else
static uint32_t _atomic_cas_up(volatile uint32_t *, uint32_t, uint32_t);
#endif
static uint32_t (*_atomic_cas_fn)(volatile uint32_t *, uint32_t, uint32_t) =
_atomic_cas_up;
RAS_DECL(_atomic_cas);
#ifdef __HAVE_ATOMIC_CAS_64_UP
#ifdef __HAVE_ASM_ATOMIC_CAS_64_UP
extern uint64_t _atomic_cas_64_up(volatile uint64_t *, uint64_t, uint64_t);
#else
static uint64_t _atomic_cas_64_up(volatile uint64_t *, uint64_t, uint64_t);
#endif
static uint64_t (*_atomic_cas_64_fn)(volatile uint64_t *, uint64_t, uint64_t) =
_atomic_cas_64_up;
RAS_DECL(_atomic_cas_64);
#endif
#ifdef __HAVE_ASM_ATOMIC_CAS_16_UP
extern uint16_t _atomic_cas_16_up(volatile uint16_t *, uint16_t, uint16_t);
#else
static uint16_t _atomic_cas_16_up(volatile uint16_t *, uint16_t, uint16_t);
#endif
static uint16_t (*_atomic_cas_16_fn)(volatile uint16_t *, uint16_t, uint16_t) =
_atomic_cas_16_up;
RAS_DECL(_atomic_cas_16);
#ifdef __HAVE_ASM_ATOMIC_CAS_8_UP
extern uint8_t _atomic_cas_8_up(volatile uint8_t *, uint8_t, uint8_t);
#else
static uint8_t _atomic_cas_8_up(volatile uint8_t *, uint8_t, uint8_t);
#endif
static uint8_t (*_atomic_cas_8_fn)(volatile uint8_t *, uint8_t, uint8_t) =
_atomic_cas_8_up;
RAS_DECL(_atomic_cas_8);
void __libc_atomic_init(void) __attribute__ ((visibility("hidden")));
#ifndef __HAVE_ASM_ATOMIC_CAS_UP
static uint32_t
_atomic_cas_up(volatile uint32_t *ptr, uint32_t old, uint32_t new)
{
uint32_t ret;
RAS_START(_atomic_cas);
ret = *ptr;
if (__predict_false(ret != old)) {
return ret;
}
*ptr = new;
RAS_END(_atomic_cas);
return ret;
}
#endif
#if defined(__HAVE_ATOMIC_CAS_64_UP) && !defined(__HAVE_ASM_ATOMIC_CAS_64_UP)
static uint64_t
_atomic_cas_64_up(volatile uint64_t *ptr, uint64_t old, uint64_t new)
{
uint64_t ret;
RAS_START(_atomic_cas_64);
ret = *ptr;
if (__predict_false(ret != old)) {
return ret;
}
*ptr = new;
RAS_END(_atomic_cas_64);
return ret;
}
#endif
#ifndef __HAVE_ASM_ATOMIC_CAS_16_UP
static uint16_t
_atomic_cas_16_up(volatile uint16_t *ptr, uint16_t old, uint16_t new)
{
uint16_t ret;
RAS_START(_atomic_cas_16);
ret = *ptr;
if (__predict_false(ret != old)) {
return ret;
}
*ptr = new;
RAS_END(_atomic_cas_16);
return ret;
}
#endif
#ifndef __HAVE_ASM_ATOMIC_CAS_8_UP
static uint8_t
_atomic_cas_8_up(volatile uint8_t *ptr, uint8_t old, uint8_t new)
{
uint8_t ret;
RAS_START(_atomic_cas_8);
ret = *ptr;
if (__predict_false(ret != old)) {
return ret;
}
*ptr = new;
RAS_END(_atomic_cas_8);
return ret;
}
#endif
static uint32_t
_atomic_cas_mp(volatile uint32_t *ptr, uint32_t old, uint32_t new)
{
__cpu_simple_lock_t *lock;
uint32_t ret;
lock = &atomic_locks[HASH(ptr)];
__cpu_simple_lock(lock);
ret = *ptr;
if (__predict_true(ret == old)) {
*ptr = new;
}
__cpu_simple_unlock(lock);
return ret;
}
#ifdef __HAVE_ATOMIC_CAS_64_UP
static uint64_t
_atomic_cas_64_mp(volatile uint64_t *ptr, uint64_t old, uint64_t new)
{
__cpu_simple_lock_t *lock;
uint64_t ret;
lock = &atomic_locks[HASH(ptr)];
__cpu_simple_lock(lock);
ret = *ptr;
if (__predict_true(ret == old)) {
*ptr = new;
}
__cpu_simple_unlock(lock);
return ret;
}
#endif
static uint16_t
_atomic_cas_16_mp(volatile uint16_t *ptr, uint16_t old, uint16_t new)
{
__cpu_simple_lock_t *lock;
uint16_t ret;
lock = &atomic_locks[HASH(ptr)];
__cpu_simple_lock(lock);
ret = *ptr;
if (__predict_true(ret == old)) {
*ptr = new;
}
__cpu_simple_unlock(lock);
return ret;
}
static uint8_t
_atomic_cas_8_mp(volatile uint8_t *ptr, uint8_t old, uint8_t new)
{
__cpu_simple_lock_t *lock;
uint8_t ret;
lock = &atomic_locks[HASH(ptr)];
__cpu_simple_lock(lock);
ret = *ptr;
if (__predict_true(ret == old)) {
*ptr = new;
}
__cpu_simple_unlock(lock);
return ret;
}
uint32_t
_atomic_cas_32(volatile uint32_t *ptr, uint32_t old, uint32_t new)
{
return (*_atomic_cas_fn)(ptr, old, new);
}
#ifdef __HAVE_ATOMIC_CAS_64_UP
uint64_t _atomic_cas_64(volatile uint64_t *, uint64_t, uint64_t);
uint64_t
_atomic_cas_64(volatile uint64_t *ptr, uint64_t old, uint64_t new)
{
return (*_atomic_cas_64_fn)(ptr, old, new);
}
#endif
uint16_t
_atomic_cas_16(volatile uint16_t *ptr, uint16_t old, uint16_t new)
{
return (*_atomic_cas_16_fn)(ptr, old, new);
}
uint8_t _atomic_cas_8(volatile uint8_t *, uint8_t, uint8_t);
uint8_t
_atomic_cas_8(volatile uint8_t *ptr, uint8_t old, uint8_t new)
{
return (*_atomic_cas_8_fn)(ptr, old, new);
}
void __section(".text.startup")
__libc_atomic_init(void)
{
int ncpu, mib[2];
size_t len;
_atomic_cas_fn = _atomic_cas_mp;
#ifdef __HAVE_ATOMIC_CAS_64_UP
_atomic_cas_64_fn = _atomic_cas_64_mp;
#endif
_atomic_cas_16_fn = _atomic_cas_16_mp;
_atomic_cas_8_fn = _atomic_cas_8_mp;
mib[0] = CTL_HW;
mib[1] = HW_NCPU;
len = sizeof(ncpu);
if (sysctl(mib, 2, &ncpu, &len, NULL, 0) == -1)
return;
if (ncpu > 1)
return;
if (rasctl(RAS_ADDR(_atomic_cas), RAS_SIZE(_atomic_cas),
RAS_INSTALL) == 0) {
_atomic_cas_fn = _atomic_cas_up;
return;
}
#ifdef __HAVE_ATOMIC_CAS_64_UP
if (rasctl(RAS_ADDR(_atomic_cas_64), RAS_SIZE(_atomic_cas_64),
RAS_INSTALL) == 0) {
_atomic_cas_64_fn = _atomic_cas_64_up;
return;
}
#endif
if (rasctl(RAS_ADDR(_atomic_cas_16), RAS_SIZE(_atomic_cas_16),
RAS_INSTALL) == 0) {
_atomic_cas_16_fn = _atomic_cas_16_up;
return;
}
if (rasctl(RAS_ADDR(_atomic_cas_8), RAS_SIZE(_atomic_cas_8),
RAS_INSTALL) == 0) {
_atomic_cas_8_fn = _atomic_cas_8_up;
return;
}
}
#undef atomic_cas_32
#undef atomic_cas_uint
#undef atomic_cas_ulong
#undef atomic_cas_ptr
#undef atomic_cas_32_ni
#undef atomic_cas_uint_ni
#undef atomic_cas_ulong_ni
#undef atomic_cas_ptr_ni
atomic_op_alias(atomic_cas_32,_atomic_cas_32)
atomic_op_alias(atomic_cas_uint,_atomic_cas_32)
__strong_alias(_atomic_cas_uint,_atomic_cas_32)
atomic_op_alias(atomic_cas_ulong,_atomic_cas_32)
__strong_alias(_atomic_cas_ulong,_atomic_cas_32)
atomic_op_alias(atomic_cas_ptr,_atomic_cas_32)
__strong_alias(_atomic_cas_ptr,_atomic_cas_32)
atomic_op_alias(atomic_cas_32_ni,_atomic_cas_32)
__strong_alias(_atomic_cas_32_ni,_atomic_cas_32)
atomic_op_alias(atomic_cas_uint_ni,_atomic_cas_32)
__strong_alias(_atomic_cas_uint_ni,_atomic_cas_32)
atomic_op_alias(atomic_cas_ulong_ni,_atomic_cas_32)
__strong_alias(_atomic_cas_ulong_ni,_atomic_cas_32)
atomic_op_alias(atomic_cas_ptr_ni,_atomic_cas_32)
__strong_alias(_atomic_cas_ptr_ni,_atomic_cas_32)
//atomic_op_alias(atomic_cas_16,_atomic_cas_16)
//atomic_op_alias(atomic_cas_16_ni,_atomic_cas_16)
//atomic_op_alias(atomic_cas_8,_atomic_cas_8)
//atomic_op_alias(atomic_cas_8_ni,_atomic_cas_8)
#ifdef __HAVE_ATOMIC_CAS_64_UP
atomic_op_alias(atomic_cas_64_ni,_atomic_cas_64)
__strong_alias(_atomic_cas_64_ni,_atomic_cas_64)
crt_alias(__sync_val_compare_and_swap_8,_atomic_cas_64)
#endif
crt_alias(__sync_val_compare_and_swap_4,_atomic_cas_32)
crt_alias(__sync_val_compare_and_swap_2,_atomic_cas_16)
crt_alias(__sync_val_compare_and_swap_1,_atomic_cas_8)