Subversion Repositories HelenOS

Rev

Rev 4346 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
1 jermar 1 
/*
2071 jermar 2 
 * Copyright (c) 2001-2004 Jakub Jermar
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 
 
4345 svoboda 29 
/** @addtogroup ia32
1702 cejka 30 
 * @{
31 
 */
32 
/** @file
33 
 */
34 
 
1888 jermar 35 
#ifndef KERN_ia32_ATOMIC_H_
36 
#define KERN_ia32_ATOMIC_H_
1 jermar 37 
 
38 
#include <arch/types.h>
1100 palkovsky 39 
#include <arch/barrier.h>
40 
#include <preemption.h>
1 jermar 41 
 
475 jermar 42 
static inline void atomic_inc(atomic_t *val) {
458 decky 43 
#ifdef CONFIG_SMP
4345 svoboda 44 
    asm volatile (
45 
        "lock incl %[count]\n"
46 
        : [count] "+m" (val->count)
47 
    );
115 jermar 48 
#else
4345 svoboda 49 
    asm volatile (
50 
        "incl %[count]\n"
51 
        : [count] "+m" (val->count)
52 
    );
458 decky 53 
#endif /* CONFIG_SMP */
115 jermar 54 
}
1 jermar 55 
 
475 jermar 56 
static inline void atomic_dec(atomic_t *val) {
458 decky 57 
#ifdef CONFIG_SMP
4345 svoboda 58 
    asm volatile (
59 
        "lock decl %[count]\n"
60 
        : [count] "+m" (val->count)
61 
    );
115 jermar 62 
#else
4345 svoboda 63 
    asm volatile (
64 
        "decl %[count]\n"
4346 svoboda 65 
        : [count] "+m" (val->count)
4345 svoboda 66 
    );
458 decky 67 
#endif /* CONFIG_SMP */
115 jermar 68 
}
69 
 
1104 jermar 70 
static inline long atomic_postinc(atomic_t *val)
477 vana 71 
{
1691 palkovsky 72 
    long r = 1;
4345 svoboda 73 
 
2082 decky 74 
    asm volatile (
4345 svoboda 75 
        "lock xaddl %[r], %[count]\n"
76 
        : [count] "+m" (val->count), [r] "+r" (r)
477 vana 77 
    );
4345 svoboda 78 
 
477 vana 79 
    return r;
80 
}
81 
 
1104 jermar 82 
static inline long atomic_postdec(atomic_t *val)
477 vana 83 
{
1691 palkovsky 84 
    long r = -1;
627 jermar 85 
 
2082 decky 86 
    asm volatile (
4345 svoboda 87 
        "lock xaddl %[r], %[count]\n"
88 
        : [count] "+m" (val->count), [r] "+r"(r)
477 vana 89 
    );
627 jermar 90 
 
477 vana 91 
    return r;
92 
}
93 
 
4345 svoboda 94 
#define atomic_preinc(val)  (atomic_postinc(val) + 1)
95 
#define atomic_predec(val)  (atomic_postdec(val) - 1)
477 vana 96 
 
1780 jermar 97 
static inline uint32_t test_and_set(atomic_t *val) {
98 
    uint32_t v;
115 jermar 99 
 
2082 decky 100 
    asm volatile (
4345 svoboda 101 
        "movl $1, %[v]\n"
102 
        "xchgl %[v], %[count]\n"
103 
        : [v] "=r" (v), [count] "+m" (val->count)
115 jermar 104 
    );
105 
 
106 
    return v;
107 
}
108 
 
1104 jermar 109 
/** ia32 specific fast spinlock */
1100 palkovsky 110 
static inline void atomic_lock_arch(atomic_t *val)
111 
{
1780 jermar 112 
    uint32_t tmp;
4345 svoboda 113 
 
1100 palkovsky 114 
    preemption_disable();
2082 decky 115 
    asm volatile (
3191 svoboda 116 
        "0:\n"
4345 svoboda 117 
        "pause\n"        /* Pentium 4's HT love this instruction */
118 
        "mov %[count], %[tmp]\n"
119 
        "testl %[tmp], %[tmp]\n"
3191 svoboda 120 
        "jnz 0b\n"       /* lightweight looping on locked spinlock */
1100 palkovsky 121 
 
4345 svoboda 122 
        "incl %[tmp]\n"  /* now use the atomic operation */
123 
        "xchgl %[count], %[tmp]\n"
124 
        "testl %[tmp], %[tmp]\n"
3191 svoboda 125 
        "jnz 0b\n"
4345 svoboda 126 
        : [count] "+m" (val->count), [tmp] "=&r" (tmp)
3191 svoboda 127 
    );
1100 palkovsky 128 
    /*
129 
     * Prevent critical section code from bleeding out this way up.
130 
     */
131 
    CS_ENTER_BARRIER();
132 
}
1 jermar 133 
 
134 
#endif
1702 cejka 135 
 
1888 jermar 136 
/** @}
1702 cejka 137 
 */