mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 00:31:08 +00:00
87 lines
1.9 KiB
C
87 lines
1.9 KiB
C
/* Low-level functions for atomic operations. AM33 version.
|
|
Copyright 1999-2013 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Alexandre Oliva <aoliva@redhat.com>.
|
|
Based on ../sparc/sparc32/atomicity.h
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Library General Public License as
|
|
published by the Free Software Foundation; either version 2 of the
|
|
License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with the GNU C Library. If not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#ifndef _ATOMICITY_H
|
|
#define _ATOMICITY_H 1
|
|
|
|
#include <inttypes.h>
|
|
|
|
#define __acquire_lock(lock) \
|
|
__asm__ __volatile__("1: bset %1, (%0)\n\t" \
|
|
" beq 1b" \
|
|
: : "a" (&(lock)), "d" (1) \
|
|
: "memory")
|
|
|
|
#define __release_lock(lock) lock = 0
|
|
|
|
static int
|
|
__attribute__ ((unused))
|
|
exchange_and_add (volatile uint32_t *mem, int val)
|
|
{
|
|
static unsigned char lock;
|
|
int result;
|
|
|
|
__acquire_lock (lock);
|
|
|
|
result = *mem;
|
|
*mem += val;
|
|
|
|
__release_lock (lock);
|
|
|
|
return result;
|
|
}
|
|
|
|
static void
|
|
__attribute__ ((unused))
|
|
atomic_add (volatile uint32_t *mem, int val)
|
|
{
|
|
static unsigned char lock;
|
|
|
|
__acquire_lock (lock);
|
|
|
|
*mem += val;
|
|
|
|
__release_lock (lock);
|
|
}
|
|
|
|
static int
|
|
__attribute__ ((unused))
|
|
compare_and_swap (volatile long int *p, long int oldval, long int newval)
|
|
{
|
|
static unsigned char lock;
|
|
int ret;
|
|
|
|
__acquire_lock (lock);
|
|
|
|
if (*p != oldval)
|
|
ret = 0;
|
|
else
|
|
{
|
|
*p = newval;
|
|
ret = 1;
|
|
}
|
|
|
|
__release_lock (lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
#endif /* atomicity.h */
|