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1 | /* |
1 | /* |
2 | * Copyright (C) 2006 Jakub Jermar |
2 | * Copyright (C) 2006 Jakub Jermar |
3 | * All rights reserved. |
3 | * All rights reserved. |
4 | * |
4 | * |
5 | * Redistribution and use in source and binary forms, with or without |
5 | * Redistribution and use in source and binary forms, with or without |
6 | * modification, are permitted provided that the following conditions |
6 | * modification, are permitted provided that the following conditions |
7 | * are met: |
7 | * are met: |
8 | * |
8 | * |
9 | * - Redistributions of source code must retain the above copyright |
9 | * - Redistributions of source code must retain the above copyright |
10 | * notice, this list of conditions and the following disclaimer. |
10 | * notice, this list of conditions and the following disclaimer. |
11 | * - Redistributions in binary form must reproduce the above copyright |
11 | * - Redistributions in binary form must reproduce the above copyright |
12 | * notice, this list of conditions and the following disclaimer in the |
12 | * notice, this list of conditions and the following disclaimer in the |
13 | * documentation and/or other materials provided with the distribution. |
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 |
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. |
15 | * derived from this software without specific prior written permission. |
16 | * |
16 | * |
17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
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 |
18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
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 |
23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
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 |
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. |
26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
27 | */ |
27 | */ |
28 | 28 | ||
- | 29 | /** @addtogroup sync |
|
- | 30 | * @{ |
|
- | 31 | */ |
|
- | 32 | ||
29 | /** |
33 | /** |
30 | * @file futex.c |
34 | * @file |
31 | * @brief Kernel backend for futexes. |
35 | * @brief Kernel backend for futexes. |
32 | */ |
36 | */ |
33 | 37 | ||
34 | #include <synch/futex.h> |
38 | #include <synch/futex.h> |
35 | #include <synch/rwlock.h> |
39 | #include <synch/rwlock.h> |
36 | #include <synch/spinlock.h> |
40 | #include <synch/spinlock.h> |
37 | #include <synch/synch.h> |
41 | #include <synch/synch.h> |
38 | #include <mm/frame.h> |
42 | #include <mm/frame.h> |
39 | #include <mm/page.h> |
43 | #include <mm/page.h> |
40 | #include <mm/slab.h> |
44 | #include <mm/slab.h> |
41 | #include <proc/thread.h> |
45 | #include <proc/thread.h> |
42 | #include <proc/task.h> |
46 | #include <proc/task.h> |
43 | #include <genarch/mm/page_pt.h> |
47 | #include <genarch/mm/page_pt.h> |
44 | #include <genarch/mm/page_ht.h> |
48 | #include <genarch/mm/page_ht.h> |
45 | #include <adt/hash_table.h> |
49 | #include <adt/hash_table.h> |
46 | #include <adt/list.h> |
50 | #include <adt/list.h> |
47 | #include <arch.h> |
51 | #include <arch.h> |
48 | #include <align.h> |
52 | #include <align.h> |
49 | #include <panic.h> |
53 | #include <panic.h> |
50 | #include <errno.h> |
54 | #include <errno.h> |
51 | #include <print.h> |
55 | #include <print.h> |
52 | 56 | ||
53 | #define FUTEX_HT_SIZE 1024 /* keep it a power of 2 */ |
57 | #define FUTEX_HT_SIZE 1024 /* keep it a power of 2 */ |
54 | 58 | ||
55 | static void futex_initialize(futex_t *futex); |
59 | static void futex_initialize(futex_t *futex); |
56 | 60 | ||
57 | static futex_t *futex_find(__address paddr); |
61 | static futex_t *futex_find(__address paddr); |
58 | static index_t futex_ht_hash(__native *key); |
62 | static index_t futex_ht_hash(__native *key); |
59 | static bool futex_ht_compare(__native *key, count_t keys, link_t *item); |
63 | static bool futex_ht_compare(__native *key, count_t keys, link_t *item); |
60 | static void futex_ht_remove_callback(link_t *item); |
64 | static void futex_ht_remove_callback(link_t *item); |
61 | 65 | ||
62 | /** |
66 | /** |
63 | * Read-write lock protecting global futex hash table. |
67 | * Read-write lock protecting global futex hash table. |
64 | * It is also used to serialize access to all futex_t structures. |
68 | * It is also used to serialize access to all futex_t structures. |
65 | * Must be acquired before the task futex B+tree lock. |
69 | * Must be acquired before the task futex B+tree lock. |
66 | */ |
70 | */ |
67 | static rwlock_t futex_ht_lock; |
71 | static rwlock_t futex_ht_lock; |
68 | 72 | ||
69 | /** Futex hash table. */ |
73 | /** Futex hash table. */ |
70 | static hash_table_t futex_ht; |
74 | static hash_table_t futex_ht; |
71 | 75 | ||
72 | /** Futex hash table operations. */ |
76 | /** Futex hash table operations. */ |
73 | static hash_table_operations_t futex_ht_ops = { |
77 | static hash_table_operations_t futex_ht_ops = { |
74 | .hash = futex_ht_hash, |
78 | .hash = futex_ht_hash, |
75 | .compare = futex_ht_compare, |
79 | .compare = futex_ht_compare, |
76 | .remove_callback = futex_ht_remove_callback |
80 | .remove_callback = futex_ht_remove_callback |
77 | }; |
81 | }; |
78 | 82 | ||
79 | /** Initialize futex subsystem. */ |
83 | /** Initialize futex subsystem. */ |
80 | void futex_init(void) |
84 | void futex_init(void) |
81 | { |
85 | { |
82 | rwlock_initialize(&futex_ht_lock); |
86 | rwlock_initialize(&futex_ht_lock); |
83 | hash_table_create(&futex_ht, FUTEX_HT_SIZE, 1, &futex_ht_ops); |
87 | hash_table_create(&futex_ht, FUTEX_HT_SIZE, 1, &futex_ht_ops); |
84 | } |
88 | } |
85 | 89 | ||
86 | /** Initialize kernel futex structure. |
90 | /** Initialize kernel futex structure. |
87 | * |
91 | * |
88 | * @param futex Kernel futex structure. |
92 | * @param futex Kernel futex structure. |
89 | */ |
93 | */ |
90 | void futex_initialize(futex_t *futex) |
94 | void futex_initialize(futex_t *futex) |
91 | { |
95 | { |
92 | waitq_initialize(&futex->wq); |
96 | waitq_initialize(&futex->wq); |
93 | link_initialize(&futex->ht_link); |
97 | link_initialize(&futex->ht_link); |
94 | futex->paddr = 0; |
98 | futex->paddr = 0; |
95 | futex->refcount = 1; |
99 | futex->refcount = 1; |
96 | } |
100 | } |
97 | 101 | ||
98 | /** Sleep in futex wait queue. |
102 | /** Sleep in futex wait queue. |
99 | * |
103 | * |
100 | * @param uaddr Userspace address of the futex counter. |
104 | * @param uaddr Userspace address of the futex counter. |
101 | * @param usec If non-zero, number of microseconds this thread is willing to sleep. |
105 | * @param usec If non-zero, number of microseconds this thread is willing to sleep. |
102 | * @param flags Select mode of operation. |
106 | * @param flags Select mode of operation. |
103 | * |
107 | * |
104 | * @return One of ESYNCH_TIMEOUT, ESYNCH_OK_ATOMIC and ESYNCH_OK_BLOCKED. See synch.h. |
108 | * @return One of ESYNCH_TIMEOUT, ESYNCH_OK_ATOMIC and ESYNCH_OK_BLOCKED. See synch.h. |
105 | * If there is no physical mapping for uaddr ENOENT is returned. |
109 | * If there is no physical mapping for uaddr ENOENT is returned. |
106 | */ |
110 | */ |
107 | __native sys_futex_sleep_timeout(__address uaddr, __u32 usec, int flags) |
111 | __native sys_futex_sleep_timeout(__address uaddr, __u32 usec, int flags) |
108 | { |
112 | { |
109 | futex_t *futex; |
113 | futex_t *futex; |
110 | __address paddr; |
114 | __address paddr; |
111 | pte_t *t; |
115 | pte_t *t; |
112 | ipl_t ipl; |
116 | ipl_t ipl; |
113 | 117 | ||
114 | ipl = interrupts_disable(); |
118 | ipl = interrupts_disable(); |
115 | 119 | ||
116 | /* |
120 | /* |
117 | * Find physical address of futex counter. |
121 | * Find physical address of futex counter. |
118 | */ |
122 | */ |
119 | page_table_lock(AS, true); |
123 | page_table_lock(AS, true); |
120 | t = page_mapping_find(AS, ALIGN_DOWN(uaddr, PAGE_SIZE)); |
124 | t = page_mapping_find(AS, ALIGN_DOWN(uaddr, PAGE_SIZE)); |
121 | if (!t || !PTE_VALID(t) || !PTE_PRESENT(t)) { |
125 | if (!t || !PTE_VALID(t) || !PTE_PRESENT(t)) { |
122 | page_table_unlock(AS, true); |
126 | page_table_unlock(AS, true); |
123 | interrupts_restore(ipl); |
127 | interrupts_restore(ipl); |
124 | return (__native) ENOENT; |
128 | return (__native) ENOENT; |
125 | } |
129 | } |
126 | paddr = PTE_GET_FRAME(t) + (uaddr - ALIGN_DOWN(uaddr, PAGE_SIZE)); |
130 | paddr = PTE_GET_FRAME(t) + (uaddr - ALIGN_DOWN(uaddr, PAGE_SIZE)); |
127 | page_table_unlock(AS, true); |
131 | page_table_unlock(AS, true); |
128 | 132 | ||
129 | interrupts_restore(ipl); |
133 | interrupts_restore(ipl); |
130 | 134 | ||
131 | futex = futex_find(paddr); |
135 | futex = futex_find(paddr); |
132 | 136 | ||
133 | return (__native) waitq_sleep_timeout(&futex->wq, usec, flags | SYNCH_FLAGS_INTERRUPTIBLE); |
137 | return (__native) waitq_sleep_timeout(&futex->wq, usec, flags | SYNCH_FLAGS_INTERRUPTIBLE); |
134 | } |
138 | } |
135 | 139 | ||
136 | /** Wakeup one thread waiting in futex wait queue. |
140 | /** Wakeup one thread waiting in futex wait queue. |
137 | * |
141 | * |
138 | * @param uaddr Userspace address of the futex counter. |
142 | * @param uaddr Userspace address of the futex counter. |
139 | * |
143 | * |
140 | * @return ENOENT if there is no physical mapping for uaddr. |
144 | * @return ENOENT if there is no physical mapping for uaddr. |
141 | */ |
145 | */ |
142 | __native sys_futex_wakeup(__address uaddr) |
146 | __native sys_futex_wakeup(__address uaddr) |
143 | { |
147 | { |
144 | futex_t *futex; |
148 | futex_t *futex; |
145 | __address paddr; |
149 | __address paddr; |
146 | pte_t *t; |
150 | pte_t *t; |
147 | ipl_t ipl; |
151 | ipl_t ipl; |
148 | 152 | ||
149 | ipl = interrupts_disable(); |
153 | ipl = interrupts_disable(); |
150 | 154 | ||
151 | /* |
155 | /* |
152 | * Find physical address of futex counter. |
156 | * Find physical address of futex counter. |
153 | */ |
157 | */ |
154 | page_table_lock(AS, true); |
158 | page_table_lock(AS, true); |
155 | t = page_mapping_find(AS, ALIGN_DOWN(uaddr, PAGE_SIZE)); |
159 | t = page_mapping_find(AS, ALIGN_DOWN(uaddr, PAGE_SIZE)); |
156 | if (!t || !PTE_VALID(t) || !PTE_PRESENT(t)) { |
160 | if (!t || !PTE_VALID(t) || !PTE_PRESENT(t)) { |
157 | page_table_unlock(AS, true); |
161 | page_table_unlock(AS, true); |
158 | interrupts_restore(ipl); |
162 | interrupts_restore(ipl); |
159 | return (__native) ENOENT; |
163 | return (__native) ENOENT; |
160 | } |
164 | } |
161 | paddr = PTE_GET_FRAME(t) + (uaddr - ALIGN_DOWN(uaddr, PAGE_SIZE)); |
165 | paddr = PTE_GET_FRAME(t) + (uaddr - ALIGN_DOWN(uaddr, PAGE_SIZE)); |
162 | page_table_unlock(AS, true); |
166 | page_table_unlock(AS, true); |
163 | 167 | ||
164 | interrupts_restore(ipl); |
168 | interrupts_restore(ipl); |
165 | 169 | ||
166 | futex = futex_find(paddr); |
170 | futex = futex_find(paddr); |
167 | 171 | ||
168 | waitq_wakeup(&futex->wq, WAKEUP_FIRST); |
172 | waitq_wakeup(&futex->wq, WAKEUP_FIRST); |
169 | 173 | ||
170 | return 0; |
174 | return 0; |
171 | } |
175 | } |
172 | 176 | ||
173 | /** Find kernel address of the futex structure corresponding to paddr. |
177 | /** Find kernel address of the futex structure corresponding to paddr. |
174 | * |
178 | * |
175 | * If the structure does not exist already, a new one is created. |
179 | * If the structure does not exist already, a new one is created. |
176 | * |
180 | * |
177 | * @param paddr Physical address of the userspace futex counter. |
181 | * @param paddr Physical address of the userspace futex counter. |
178 | * |
182 | * |
179 | * @return Address of the kernel futex structure. |
183 | * @return Address of the kernel futex structure. |
180 | */ |
184 | */ |
181 | futex_t *futex_find(__address paddr) |
185 | futex_t *futex_find(__address paddr) |
182 | { |
186 | { |
183 | link_t *item; |
187 | link_t *item; |
184 | futex_t *futex; |
188 | futex_t *futex; |
185 | btree_node_t *leaf; |
189 | btree_node_t *leaf; |
186 | 190 | ||
187 | /* |
191 | /* |
188 | * Find the respective futex structure |
192 | * Find the respective futex structure |
189 | * or allocate new one if it does not exist already. |
193 | * or allocate new one if it does not exist already. |
190 | */ |
194 | */ |
191 | rwlock_read_lock(&futex_ht_lock); |
195 | rwlock_read_lock(&futex_ht_lock); |
192 | item = hash_table_find(&futex_ht, &paddr); |
196 | item = hash_table_find(&futex_ht, &paddr); |
193 | if (item) { |
197 | if (item) { |
194 | futex = hash_table_get_instance(item, futex_t, ht_link); |
198 | futex = hash_table_get_instance(item, futex_t, ht_link); |
195 | 199 | ||
196 | /* |
200 | /* |
197 | * See if the current task knows this futex. |
201 | * See if the current task knows this futex. |
198 | */ |
202 | */ |
199 | mutex_lock(&TASK->futexes_lock); |
203 | mutex_lock(&TASK->futexes_lock); |
200 | if (!btree_search(&TASK->futexes, paddr, &leaf)) { |
204 | if (!btree_search(&TASK->futexes, paddr, &leaf)) { |
201 | /* |
205 | /* |
202 | * The futex is new to the current task. |
206 | * The futex is new to the current task. |
203 | * However, we only have read access. |
207 | * However, we only have read access. |
204 | * Gain write access and try again. |
208 | * Gain write access and try again. |
205 | */ |
209 | */ |
206 | mutex_unlock(&TASK->futexes_lock); |
210 | mutex_unlock(&TASK->futexes_lock); |
207 | goto gain_write_access; |
211 | goto gain_write_access; |
208 | } |
212 | } |
209 | mutex_unlock(&TASK->futexes_lock); |
213 | mutex_unlock(&TASK->futexes_lock); |
210 | 214 | ||
211 | rwlock_read_unlock(&futex_ht_lock); |
215 | rwlock_read_unlock(&futex_ht_lock); |
212 | } else { |
216 | } else { |
213 | gain_write_access: |
217 | gain_write_access: |
214 | /* |
218 | /* |
215 | * Upgrade to writer is not currently supported, |
219 | * Upgrade to writer is not currently supported, |
216 | * therefore, it is necessary to release the read lock |
220 | * therefore, it is necessary to release the read lock |
217 | * and reacquire it as a writer. |
221 | * and reacquire it as a writer. |
218 | */ |
222 | */ |
219 | rwlock_read_unlock(&futex_ht_lock); |
223 | rwlock_read_unlock(&futex_ht_lock); |
220 | 224 | ||
221 | rwlock_write_lock(&futex_ht_lock); |
225 | rwlock_write_lock(&futex_ht_lock); |
222 | /* |
226 | /* |
223 | * Avoid possible race condition by searching |
227 | * Avoid possible race condition by searching |
224 | * the hash table once again with write access. |
228 | * the hash table once again with write access. |
225 | */ |
229 | */ |
226 | item = hash_table_find(&futex_ht, &paddr); |
230 | item = hash_table_find(&futex_ht, &paddr); |
227 | if (item) { |
231 | if (item) { |
228 | futex = hash_table_get_instance(item, futex_t, ht_link); |
232 | futex = hash_table_get_instance(item, futex_t, ht_link); |
229 | 233 | ||
230 | /* |
234 | /* |
231 | * See if this futex is known to the current task. |
235 | * See if this futex is known to the current task. |
232 | */ |
236 | */ |
233 | mutex_lock(&TASK->futexes_lock); |
237 | mutex_lock(&TASK->futexes_lock); |
234 | if (!btree_search(&TASK->futexes, paddr, &leaf)) { |
238 | if (!btree_search(&TASK->futexes, paddr, &leaf)) { |
235 | /* |
239 | /* |
236 | * The futex is new to the current task. |
240 | * The futex is new to the current task. |
237 | * Upgrade its reference count and put it to the |
241 | * Upgrade its reference count and put it to the |
238 | * current task's B+tree of known futexes. |
242 | * current task's B+tree of known futexes. |
239 | */ |
243 | */ |
240 | futex->refcount++; |
244 | futex->refcount++; |
241 | btree_insert(&TASK->futexes, paddr, futex, leaf); |
245 | btree_insert(&TASK->futexes, paddr, futex, leaf); |
242 | } |
246 | } |
243 | mutex_unlock(&TASK->futexes_lock); |
247 | mutex_unlock(&TASK->futexes_lock); |
244 | 248 | ||
245 | rwlock_write_unlock(&futex_ht_lock); |
249 | rwlock_write_unlock(&futex_ht_lock); |
246 | } else { |
250 | } else { |
247 | futex = (futex_t *) malloc(sizeof(futex_t), 0); |
251 | futex = (futex_t *) malloc(sizeof(futex_t), 0); |
248 | futex_initialize(futex); |
252 | futex_initialize(futex); |
249 | futex->paddr = paddr; |
253 | futex->paddr = paddr; |
250 | hash_table_insert(&futex_ht, &paddr, &futex->ht_link); |
254 | hash_table_insert(&futex_ht, &paddr, &futex->ht_link); |
251 | 255 | ||
252 | /* |
256 | /* |
253 | * This is the first task referencing the futex. |
257 | * This is the first task referencing the futex. |
254 | * It can be directly inserted into its |
258 | * It can be directly inserted into its |
255 | * B+tree of known futexes. |
259 | * B+tree of known futexes. |
256 | */ |
260 | */ |
257 | mutex_lock(&TASK->futexes_lock); |
261 | mutex_lock(&TASK->futexes_lock); |
258 | btree_insert(&TASK->futexes, paddr, futex, NULL); |
262 | btree_insert(&TASK->futexes, paddr, futex, NULL); |
259 | mutex_unlock(&TASK->futexes_lock); |
263 | mutex_unlock(&TASK->futexes_lock); |
260 | 264 | ||
261 | rwlock_write_unlock(&futex_ht_lock); |
265 | rwlock_write_unlock(&futex_ht_lock); |
262 | } |
266 | } |
263 | } |
267 | } |
264 | 268 | ||
265 | return futex; |
269 | return futex; |
266 | } |
270 | } |
267 | 271 | ||
268 | /** Compute hash index into futex hash table. |
272 | /** Compute hash index into futex hash table. |
269 | * |
273 | * |
270 | * @param key Address where the key (i.e. physical address of futex counter) is stored. |
274 | * @param key Address where the key (i.e. physical address of futex counter) is stored. |
271 | * |
275 | * |
272 | * @return Index into futex hash table. |
276 | * @return Index into futex hash table. |
273 | */ |
277 | */ |
274 | index_t futex_ht_hash(__native *key) |
278 | index_t futex_ht_hash(__native *key) |
275 | { |
279 | { |
276 | return *key & (FUTEX_HT_SIZE-1); |
280 | return *key & (FUTEX_HT_SIZE-1); |
277 | } |
281 | } |
278 | 282 | ||
279 | /** Compare futex hash table item with a key. |
283 | /** Compare futex hash table item with a key. |
280 | * |
284 | * |
281 | * @param key Address where the key (i.e. physical address of futex counter) is stored. |
285 | * @param key Address where the key (i.e. physical address of futex counter) is stored. |
282 | * |
286 | * |
283 | * @return True if the item matches the key. False otherwise. |
287 | * @return True if the item matches the key. False otherwise. |
284 | */ |
288 | */ |
285 | bool futex_ht_compare(__native *key, count_t keys, link_t *item) |
289 | bool futex_ht_compare(__native *key, count_t keys, link_t *item) |
286 | { |
290 | { |
287 | futex_t *futex; |
291 | futex_t *futex; |
288 | 292 | ||
289 | ASSERT(keys == 1); |
293 | ASSERT(keys == 1); |
290 | 294 | ||
291 | futex = hash_table_get_instance(item, futex_t, ht_link); |
295 | futex = hash_table_get_instance(item, futex_t, ht_link); |
292 | return *key == futex->paddr; |
296 | return *key == futex->paddr; |
293 | } |
297 | } |
294 | 298 | ||
295 | /** Callback for removal items from futex hash table. |
299 | /** Callback for removal items from futex hash table. |
296 | * |
300 | * |
297 | * @param item Item removed from the hash table. |
301 | * @param item Item removed from the hash table. |
298 | */ |
302 | */ |
299 | void futex_ht_remove_callback(link_t *item) |
303 | void futex_ht_remove_callback(link_t *item) |
300 | { |
304 | { |
301 | futex_t *futex; |
305 | futex_t *futex; |
302 | 306 | ||
303 | futex = hash_table_get_instance(item, futex_t, ht_link); |
307 | futex = hash_table_get_instance(item, futex_t, ht_link); |
304 | free(futex); |
308 | free(futex); |
305 | } |
309 | } |
306 | 310 | ||
307 | /** Remove references from futexes known to the current task. */ |
311 | /** Remove references from futexes known to the current task. */ |
308 | void futex_cleanup(void) |
312 | void futex_cleanup(void) |
309 | { |
313 | { |
310 | link_t *cur; |
314 | link_t *cur; |
311 | 315 | ||
312 | rwlock_write_lock(&futex_ht_lock); |
316 | rwlock_write_lock(&futex_ht_lock); |
313 | mutex_lock(&TASK->futexes_lock); |
317 | mutex_lock(&TASK->futexes_lock); |
314 | 318 | ||
315 | for (cur = TASK->futexes.leaf_head.next; cur != &TASK->futexes.leaf_head; cur = cur->next) { |
319 | for (cur = TASK->futexes.leaf_head.next; cur != &TASK->futexes.leaf_head; cur = cur->next) { |
316 | btree_node_t *node; |
320 | btree_node_t *node; |
317 | int i; |
321 | int i; |
318 | 322 | ||
319 | node = list_get_instance(cur, btree_node_t, leaf_link); |
323 | node = list_get_instance(cur, btree_node_t, leaf_link); |
320 | for (i = 0; i < node->keys; i++) { |
324 | for (i = 0; i < node->keys; i++) { |
321 | futex_t *ftx; |
325 | futex_t *ftx; |
322 | __address paddr = node->key[i]; |
326 | __address paddr = node->key[i]; |
323 | 327 | ||
324 | ftx = (futex_t *) node->value[i]; |
328 | ftx = (futex_t *) node->value[i]; |
325 | if (--ftx->refcount == 0) |
329 | if (--ftx->refcount == 0) |
326 | hash_table_remove(&futex_ht, &paddr, 1); |
330 | hash_table_remove(&futex_ht, &paddr, 1); |
327 | } |
331 | } |
328 | } |
332 | } |
329 | 333 | ||
330 | mutex_unlock(&TASK->futexes_lock); |
334 | mutex_unlock(&TASK->futexes_lock); |
331 | rwlock_write_unlock(&futex_ht_lock); |
335 | rwlock_write_unlock(&futex_ht_lock); |
332 | } |
336 | } |
- | 337 | ||
- | 338 | /** @} |
|
- | 339 | */ |
|
- | 340 | ||
333 | 341 |