Subversion Repositories HelenOS

Rev

Rev 2462 | Rev 3149 | Go to most recent revision | 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
 
1888 jermar 29
/** @addtogroup sync
1702 cejka 30
 * @{
31
 */
32
/** @file
33
 */
34
 
1888 jermar 35
#ifndef KERN_SPINLOCK_H_
36
#define KERN_SPINLOCK_H_
1 jermar 37
 
38
#include <arch/types.h>
223 jermar 39
#include <preemption.h>
1104 jermar 40
#include <atomic.h>
1100 palkovsky 41
#include <debug.h>
1 jermar 42
 
458 decky 43
#ifdef CONFIG_SMP
2085 decky 44
typedef struct {
552 palkovsky 45
#ifdef CONFIG_DEBUG_SPINLOCK
46
    char *name;
47
#endif
625 palkovsky 48
    atomic_t val;
2085 decky 49
} spinlock_t;
1 jermar 50
 
623 jermar 51
/*
52
 * SPINLOCK_DECLARE is to be used for dynamically allocated spinlocks,
53
 * where the lock gets initialized in run time.
54
 */
55
#define SPINLOCK_DECLARE(slname)    spinlock_t slname
2093 decky 56
#define SPINLOCK_EXTERN(slname)     extern spinlock_t slname
623 jermar 57
 
58
/*
59
 * SPINLOCK_INITIALIZE is to be used for statically allocated spinlocks.
60
 * It declares and initializes the lock.
61
 */
62
#ifdef CONFIG_DEBUG_SPINLOCK
63
#define SPINLOCK_INITIALIZE(slname)     \
64
    spinlock_t slname = {       \
65
        .name = #slname,    \
625 palkovsky 66
        .val = { 0 }        \
623 jermar 67
    }
68
#else
69
#define SPINLOCK_INITIALIZE(slname)     \
70
    spinlock_t slname = {       \
625 palkovsky 71
        .val = { 0 }        \
623 jermar 72
    }
73
#endif
74
 
552 palkovsky 75
extern void spinlock_initialize(spinlock_t *sl, char *name);
1 jermar 76
extern int spinlock_trylock(spinlock_t *sl);
1100 palkovsky 77
extern void spinlock_lock_debug(spinlock_t *sl);
1 jermar 78
 
1100 palkovsky 79
#ifdef CONFIG_DEBUG_SPINLOCK
80
#  define spinlock_lock(x) spinlock_lock_debug(x)
1 jermar 81
#else
1100 palkovsky 82
#  define spinlock_lock(x) atomic_lock_arch(&(x)->val)
83
#endif
1 jermar 84
 
1100 palkovsky 85
/** Unlock spinlock
86
 *
87
 * Unlock spinlock.
88
 *
89
 * @param sl Pointer to spinlock_t structure.
90
 */
91
static inline void spinlock_unlock(spinlock_t *sl)
92
{
93
    ASSERT(atomic_get(&sl->val) != 0);
94
 
95
    /*
96
     * Prevent critical section code from bleeding out this way down.
97
     */
98
    CS_LEAVE_BARRIER();
99
 
2089 decky 100
    atomic_set(&sl->val, 0);
1100 palkovsky 101
    preemption_enable();
102
}
103
 
2183 jermar 104
#ifdef CONFIG_DEBUG_SPINLOCK
105
 
106
extern int printf(const char *, ...);
107
 
108
#define DEADLOCK_THRESHOLD      100000000
109
#define DEADLOCK_PROBE_INIT(pname)  count_t pname = 0
110
#define DEADLOCK_PROBE(pname, value)                    \
111
    if ((pname)++ > (value)) {                  \
112
        (pname) = 0;                        \
113
        printf("Deadlock probe %s: exceeded threshold %d\n",    \
114
            "cpu%d: function=%s, line=%d\n",            \
2462 jermar 115
            #pname, (value), CPU->id, __func__, __LINE__);  \
2183 jermar 116
    }
1100 palkovsky 117
#else
2183 jermar 118
#define DEADLOCK_PROBE_INIT(pname)
119
#define DEADLOCK_PROBE(pname, value)
120
#endif
1100 palkovsky 121
 
2183 jermar 122
#else
123
 
623 jermar 124
/* On UP systems, spinlocks are effectively left out. */
125
#define SPINLOCK_DECLARE(name)
2093 decky 126
#define SPINLOCK_EXTERN(name)
623 jermar 127
#define SPINLOCK_INITIALIZE(name)
1 jermar 128
 
2089 decky 129
#define spinlock_initialize(x, name)
223 jermar 130
#define spinlock_lock(x)        preemption_disable()
131
#define spinlock_trylock(x)         (preemption_disable(), 1)
132
#define spinlock_unlock(x)      preemption_enable()
1 jermar 133
 
2183 jermar 134
#define DEADLOCK_PROBE_INIT(pname)
135
#define DEADLOCK_PROBE(pname, value)
136
 
1 jermar 137
#endif
138
 
139
#endif
1702 cejka 140
 
1888 jermar 141
/** @}
1702 cejka 142
 */