|
1 /* Threading for AtheOS. |
|
2 Based on thread_beos.h. */ |
|
3 |
|
4 #include <atheos/threads.h> |
|
5 #include <atheos/semaphore.h> |
|
6 #include <atheos/atomic.h> |
|
7 #include <errno.h> |
|
8 #include <string.h> |
|
9 |
|
10 /* Missing decl from threads.h */ |
|
11 extern int exit_thread(int); |
|
12 |
|
13 |
|
14 /* Undefine FASTLOCK to play with simple semaphores. */ |
|
15 #define FASTLOCK |
|
16 |
|
17 |
|
18 #ifdef FASTLOCK |
|
19 |
|
20 /* Use an atomic counter and a semaphore for maximum speed. */ |
|
21 typedef struct fastmutex { |
|
22 sem_id sem; |
|
23 atomic_t count; |
|
24 } fastmutex_t; |
|
25 |
|
26 |
|
27 static int fastmutex_create(const char *name, fastmutex_t * mutex); |
|
28 static int fastmutex_destroy(fastmutex_t * mutex); |
|
29 static int fastmutex_lock(fastmutex_t * mutex); |
|
30 static int fastmutex_timedlock(fastmutex_t * mutex, bigtime_t timeout); |
|
31 static int fastmutex_unlock(fastmutex_t * mutex); |
|
32 |
|
33 |
|
34 static int fastmutex_create(const char *name, fastmutex_t * mutex) |
|
35 { |
|
36 mutex->count = 0; |
|
37 mutex->sem = create_semaphore(name, 0, 0); |
|
38 return (mutex->sem < 0) ? -1 : 0; |
|
39 } |
|
40 |
|
41 |
|
42 static int fastmutex_destroy(fastmutex_t * mutex) |
|
43 { |
|
44 if (fastmutex_timedlock(mutex, 0) == 0 || errno == EWOULDBLOCK) { |
|
45 return delete_semaphore(mutex->sem); |
|
46 } |
|
47 return 0; |
|
48 } |
|
49 |
|
50 |
|
51 static int fastmutex_lock(fastmutex_t * mutex) |
|
52 { |
|
53 atomic_t prev = atomic_add(&mutex->count, 1); |
|
54 if (prev > 0) |
|
55 return lock_semaphore(mutex->sem); |
|
56 return 0; |
|
57 } |
|
58 |
|
59 |
|
60 static int fastmutex_timedlock(fastmutex_t * mutex, bigtime_t timeout) |
|
61 { |
|
62 atomic_t prev = atomic_add(&mutex->count, 1); |
|
63 if (prev > 0) |
|
64 return lock_semaphore_x(mutex->sem, 1, 0, timeout); |
|
65 return 0; |
|
66 } |
|
67 |
|
68 |
|
69 static int fastmutex_unlock(fastmutex_t * mutex) |
|
70 { |
|
71 atomic_t prev = atomic_add(&mutex->count, -1); |
|
72 if (prev > 1) |
|
73 return unlock_semaphore(mutex->sem); |
|
74 return 0; |
|
75 } |
|
76 |
|
77 |
|
78 #endif /* FASTLOCK */ |
|
79 |
|
80 |
|
81 /* |
|
82 * Initialization. |
|
83 * |
|
84 */ |
|
85 static void PyThread__init_thread(void) |
|
86 { |
|
87 /* Do nothing. */ |
|
88 return; |
|
89 } |
|
90 |
|
91 |
|
92 /* |
|
93 * Thread support. |
|
94 * |
|
95 */ |
|
96 |
|
97 static atomic_t thread_count = 0; |
|
98 |
|
99 long PyThread_start_new_thread(void (*func) (void *), void *arg) |
|
100 { |
|
101 status_t success = -1; |
|
102 thread_id tid; |
|
103 char name[OS_NAME_LENGTH]; |
|
104 atomic_t this_thread; |
|
105 |
|
106 dprintf(("PyThread_start_new_thread called\n")); |
|
107 |
|
108 this_thread = atomic_add(&thread_count, 1); |
|
109 PyOS_snprintf(name, sizeof(name), "python thread (%d)", this_thread); |
|
110 |
|
111 tid = spawn_thread(name, func, NORMAL_PRIORITY, 0, arg); |
|
112 if (tid < 0) { |
|
113 dprintf(("PyThread_start_new_thread spawn_thread failed: %s\n", strerror(errno))); |
|
114 } else { |
|
115 success = resume_thread(tid); |
|
116 if (success < 0) { |
|
117 dprintf(("PyThread_start_new_thread resume_thread failed: %s\n", strerror(errno))); |
|
118 } |
|
119 } |
|
120 |
|
121 return (success < 0 ? -1 : tid); |
|
122 } |
|
123 |
|
124 |
|
125 long PyThread_get_thread_ident(void) |
|
126 { |
|
127 return get_thread_id(NULL); |
|
128 } |
|
129 |
|
130 |
|
131 static void do_PyThread_exit_thread(int no_cleanup) |
|
132 { |
|
133 dprintf(("PyThread_exit_thread called\n")); |
|
134 |
|
135 /* Thread-safe way to read a variable without a mutex: */ |
|
136 if (atomic_add(&thread_count, 0) == 0) { |
|
137 /* No threads around, so exit main(). */ |
|
138 if (no_cleanup) |
|
139 _exit(0); |
|
140 else |
|
141 exit(0); |
|
142 } else { |
|
143 /* We're a thread */ |
|
144 exit_thread(0); |
|
145 } |
|
146 } |
|
147 |
|
148 |
|
149 void PyThread_exit_thread(void) |
|
150 { |
|
151 do_PyThread_exit_thread(0); |
|
152 } |
|
153 |
|
154 |
|
155 void PyThread__exit_thread(void) |
|
156 { |
|
157 do_PyThread_exit_thread(1); |
|
158 } |
|
159 |
|
160 |
|
161 #ifndef NO_EXIT_PROG |
|
162 static void do_PyThread_exit_prog(int status, int no_cleanup) |
|
163 { |
|
164 dprintf(("PyThread_exit_prog(%d) called\n", status)); |
|
165 |
|
166 /* No need to do anything, the threads get torn down if main()exits. */ |
|
167 if (no_cleanup) |
|
168 _exit(status); |
|
169 else |
|
170 exit(status); |
|
171 } |
|
172 |
|
173 |
|
174 void PyThread_exit_prog(int status) |
|
175 { |
|
176 do_PyThread_exit_prog(status, 0); |
|
177 } |
|
178 |
|
179 |
|
180 void PyThread__exit_prog(int status) |
|
181 { |
|
182 do_PyThread_exit_prog(status, 1); |
|
183 } |
|
184 #endif /* NO_EXIT_PROG */ |
|
185 |
|
186 |
|
187 /* |
|
188 * Lock support. |
|
189 * |
|
190 */ |
|
191 |
|
192 static atomic_t lock_count = 0; |
|
193 |
|
194 PyThread_type_lock PyThread_allocate_lock(void) |
|
195 { |
|
196 #ifdef FASTLOCK |
|
197 fastmutex_t *lock; |
|
198 #else |
|
199 sem_id sema; |
|
200 #endif |
|
201 char name[OS_NAME_LENGTH]; |
|
202 atomic_t this_lock; |
|
203 |
|
204 dprintf(("PyThread_allocate_lock called\n")); |
|
205 |
|
206 #ifdef FASTLOCK |
|
207 lock = (fastmutex_t *) malloc(sizeof(fastmutex_t)); |
|
208 if (lock == NULL) { |
|
209 dprintf(("PyThread_allocate_lock failed: out of memory\n")); |
|
210 return (PyThread_type_lock) NULL; |
|
211 } |
|
212 #endif |
|
213 this_lock = atomic_add(&lock_count, 1); |
|
214 PyOS_snprintf(name, sizeof(name), "python lock (%d)", this_lock); |
|
215 |
|
216 #ifdef FASTLOCK |
|
217 if (fastmutex_create(name, lock) < 0) { |
|
218 dprintf(("PyThread_allocate_lock failed: %s\n", |
|
219 strerror(errno))); |
|
220 free(lock); |
|
221 lock = NULL; |
|
222 } |
|
223 dprintf(("PyThread_allocate_lock()-> %p\n", lock)); |
|
224 return (PyThread_type_lock) lock; |
|
225 #else |
|
226 sema = create_semaphore(name, 1, 0); |
|
227 if (sema < 0) { |
|
228 dprintf(("PyThread_allocate_lock failed: %s\n", |
|
229 strerror(errno))); |
|
230 sema = 0; |
|
231 } |
|
232 dprintf(("PyThread_allocate_lock()-> %p\n", sema)); |
|
233 return (PyThread_type_lock) sema; |
|
234 #endif |
|
235 } |
|
236 |
|
237 |
|
238 void PyThread_free_lock(PyThread_type_lock lock) |
|
239 { |
|
240 dprintf(("PyThread_free_lock(%p) called\n", lock)); |
|
241 |
|
242 #ifdef FASTLOCK |
|
243 if (fastmutex_destroy((fastmutex_t *) lock) < 0) { |
|
244 dprintf(("PyThread_free_lock(%p) failed: %s\n", lock, |
|
245 strerror(errno))); |
|
246 } |
|
247 free(lock); |
|
248 #else |
|
249 if (delete_semaphore((sem_id) lock) < 0) { |
|
250 dprintf(("PyThread_free_lock(%p) failed: %s\n", lock, |
|
251 strerror(errno))); |
|
252 } |
|
253 #endif |
|
254 } |
|
255 |
|
256 |
|
257 int PyThread_acquire_lock(PyThread_type_lock lock, int waitflag) |
|
258 { |
|
259 int retval; |
|
260 |
|
261 dprintf(("PyThread_acquire_lock(%p, %d) called\n", lock, |
|
262 waitflag)); |
|
263 |
|
264 #ifdef FASTLOCK |
|
265 if (waitflag) |
|
266 retval = fastmutex_lock((fastmutex_t *) lock); |
|
267 else |
|
268 retval = fastmutex_timedlock((fastmutex_t *) lock, 0); |
|
269 #else |
|
270 if (waitflag) |
|
271 retval = lock_semaphore((sem_id) lock); |
|
272 else |
|
273 retval = lock_semaphore_x((sem_id) lock, 1, 0, 0); |
|
274 #endif |
|
275 if (retval < 0) { |
|
276 dprintf(("PyThread_acquire_lock(%p, %d) failed: %s\n", |
|
277 lock, waitflag, strerror(errno))); |
|
278 } |
|
279 dprintf(("PyThread_acquire_lock(%p, %d)-> %d\n", lock, waitflag, |
|
280 retval)); |
|
281 return retval < 0 ? 0 : 1; |
|
282 } |
|
283 |
|
284 |
|
285 void PyThread_release_lock(PyThread_type_lock lock) |
|
286 { |
|
287 dprintf(("PyThread_release_lock(%p) called\n", lock)); |
|
288 |
|
289 #ifdef FASTLOCK |
|
290 if (fastmutex_unlock((fastmutex_t *) lock) < 0) { |
|
291 dprintf(("PyThread_release_lock(%p) failed: %s\n", lock, |
|
292 strerror(errno))); |
|
293 } |
|
294 #else |
|
295 if (unlock_semaphore((sem_id) lock) < 0) { |
|
296 dprintf(("PyThread_release_lock(%p) failed: %s\n", lock, |
|
297 strerror(errno))); |
|
298 } |
|
299 #endif |
|
300 } |