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Rev 4516 Rev 4526
Line 88... Line 88...
88 
    futex_up(&async_futex);
 88 
    futex_up(&async_futex);
89 
}
 89 
}
90 
 
 90 
 
91 
void fibril_rwlock_initialize(fibril_rwlock_t *frw)
 91 
void fibril_rwlock_initialize(fibril_rwlock_t *frw)
92 
{
 92 
{
- 
 
 93 
    frw->writers = 0;
- 
 
 94 
    frw->readers = 0;
93 
    fibril_mutex_initialize(&frw->fm);
 95 
    list_initialize(&frw->waiters);
94 
}
 96 
}
95 
 
 97 
 
96 
void fibril_rwlock_read_lock(fibril_rwlock_t *frw)
 98 
void fibril_rwlock_read_lock(fibril_rwlock_t *frw)
97 
{
 99 
{
98 
    fibril_mutex_lock(&frw->fm);
 100 
    futex_down(&async_futex);
- 
 
 101 
    if (frw->writers) {
- 
 
 102 
        fibril_t *f = (fibril_t *) fibril_get_id();
- 
 
 103 
        f->flags &= ~FIBRIL_WRITER;
- 
 
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        list_append(&f->link, &frw->waiters);
- 
 
 105 
        fibril_switch(FIBRIL_TO_MANAGER);
- 
 
 106 
    } else {
- 
 
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        frw->readers++;
- 
 
 108 
        futex_up(&async_futex);
- 
 
 109 
    }
99 
}
 110 
}
100 
 
 111 
 
101 
void fibril_rwlock_write_lock(fibril_rwlock_t *frw)
 112 
void fibril_rwlock_write_lock(fibril_rwlock_t *frw)
102 
{
 113 
{
- 
 
 114 
    futex_down(&async_futex);
- 
 
 115 
    if (frw->writers || frw->readers) {
- 
 
 116 
        fibril_t *f = (fibril_t *) fibril_get_id();
- 
 
 117 
        f->flags |= FIBRIL_WRITER;
- 
 
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        list_append(&f->link, &frw->waiters);
- 
 
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        fibril_switch(FIBRIL_TO_MANAGER);
- 
 
 120 
    } else {
- 
 
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        frw->writers++;
- 
 
 122 
        futex_up(&async_futex);
- 
 
 123 
    }
- 
 
 124 
}
- 
 
 125 
 
- 
 
 126 
static void _fibril_rwlock_common_unlock(fibril_rwlock_t *frw)
- 
 
 127 
{
- 
 
 128 
    futex_down(&async_futex);
- 
 
 129 
    assert(frw->readers || (frw->writers == 1));
- 
 
 130 
    if (frw->readers) {
- 
 
 131 
        if (--frw->readers)
- 
 
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            goto out;
- 
 
 133 
    } else {
- 
 
 134 
        frw->writers--;
- 
 
 135 
    }
- 
 
 136 
   
- 
 
 137 
    assert(!frw->readers && !frw->writers);
- 
 
 138 
   
- 
 
 139 
    while (!list_empty(&frw->waiters)) {
- 
 
 140 
        link_t *tmp = frw->waiters.next;
- 
 
 141 
        fibril_t *f = list_get_instance(tmp, fibril_t, link);
- 
 
 142 
       
- 
 
 143 
        if (f->flags & FIBRIL_WRITER) {
- 
 
 144 
            if (frw->readers)
- 
 
 145 
                break;
- 
 
 146 
            list_remove(&f->link);
- 
 
 147 
            fibril_add_ready((fid_t) f);
- 
 
 148 
            frw->writers++;
- 
 
 149 
            break;
- 
 
 150 
        } else {
- 
 
 151 
            list_remove(&f->link);
103 
    fibril_mutex_lock(&frw->fm);
 152 
            fibril_add_ready((fid_t) f);
- 
 
 153 
            frw->readers++;
- 
 
 154 
        }
- 
 
 155 
    }
- 
 
 156 
out:
- 
 
 157 
    futex_up(&async_futex);
104 
}
 158 
}
105 
 
 159 
 
106 
void fibril_rwlock_read_unlock(fibril_rwlock_t *frw)
 160 
void fibril_rwlock_read_unlock(fibril_rwlock_t *frw)
107 
{
 161 
{
108 
    fibril_mutex_unlock(&frw->fm);
 162 
    _fibril_rwlock_common_unlock(frw);
109 
}
 163 
}
110 
 
 164 
 
111 
void fibril_rwlock_write_unlock(fibril_rwlock_t *frw)
 165 
void fibril_rwlock_write_unlock(fibril_rwlock_t *frw)
112 
{
 166 
{
113 
    fibril_mutex_unlock(&frw->fm);
 167 
    _fibril_rwlock_common_unlock(frw);
114 
}
 168 
}
115 
 
 169 
 
116 
/** @}
 170 
/** @}
117 
 */
 171 
 */