Subversion Repositories HelenOS-historic

Rev

Rev 625 | Rev 1024 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
1 jermar 1 
/*
112 jermar 2 
 * Copyright (C) 2005 Ondrej Palkovsky
1 jermar 3 
 * All rights reserved.
4 
 *
5 
 * Redistribution and use in source and binary forms, with or without
6 
 * modification, are permitted provided that the following conditions
7 
 * are met:
8 
 *
9 
 * - Redistributions of source code must retain the above copyright
10 
 *   notice, this list of conditions and the following disclaimer.
11 
 * - Redistributions in binary form must reproduce the above copyright
12 
 *   notice, this list of conditions and the following disclaimer in the
13 
 *   documentation and/or other materials provided with the distribution.
14 
 * - The name of the author may not be used to endorse or promote products
15 
 *   derived from this software without specific prior written permission.
16 
 *
17 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 
 */
28 
 
341 jermar 29 
#ifndef __mips32_ATOMIC_H__
30 
#define __mips32_ATOMIC_H__
1 jermar 31 
 
475 jermar 32 
#include <arch/types.h>
33 
 
483 jermar 34 
#define atomic_inc(x)   ((void) atomic_add(x, 1))
35 
#define atomic_dec(x)   ((void) atomic_add(x, -1))
1 jermar 36 
 
483 jermar 37 
#define atomic_inc_pre(x) (atomic_add(x, 1) - 1)
38 
#define atomic_dec_pre(x) (atomic_add(x, -1) + 1)
477 vana 39 
 
483 jermar 40 
#define atomic_inc_post(x) atomic_add(x, 1)
41 
#define atomic_dec_post(x) atomic_add(x, -1)
477 vana 42 
 
43 
 
625 palkovsky 44 
typedef struct { volatile __u32 count; } atomic_t;
475 jermar 45 
 
483 jermar 46 
/* Atomic addition of immediate value.
111 palkovsky 47 
 *
483 jermar 48 
 * @param val Memory location to which will be the immediate value added.
49 
 * @param i Signed immediate that will be added to *val.
50 
 *
51 
 * @return Value after addition.
111 palkovsky 52 
 */
627 jermar 53 
static inline count_t atomic_add(atomic_t *val, int i)
111 palkovsky 54 
{
627 jermar 55 
    count_t tmp, v;
111 palkovsky 56 
 
483 jermar 57 
    __asm__ volatile (
111 palkovsky 58 
        "1:\n"
483 jermar 59 
        "   ll %0, %1\n"
60 
        "   addiu %0, %0, %3\n" /* same as addi, but never traps on overflow */
61 
        "       move %2, %0\n"
62 
        "   sc %0, %1\n"
63 
        "   beq %0, %4, 1b\n"   /* if the atomic operation failed, try again */
64 
        /*  nop */      /* nop is inserted automatically by compiler */
625 palkovsky 65 
        : "=r" (tmp), "=m" (val->count), "=r" (v)
483 jermar 66 
        : "i" (i), "i" (0)
111 palkovsky 67 
        );
68 
 
483 jermar 69 
    return v;
111 palkovsky 70 
}
71 
 
625 palkovsky 72 
/* Reads/writes are atomic on mips for 4-bytes */
111 palkovsky 73 
 
625 palkovsky 74 
static inline void atomic_set(atomic_t *val, __u32 i)
75 
{
76 
    val->count = i;
77 
}
78 
 
79 
static inline __u32 atomic_get(atomic_t *val)
80 
{
81 
    return val->count;
82 
}
83 
 
1 jermar 84 
#endif