1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
|
/*
ChibiOS/RT - Copyright (C) 2006-2007 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @addtogroup Threads
* @{
*/
#ifndef _THREADS_H_
#define _THREADS_H_
/**
* Structure representing a thread.
* @extends ThreadsQueue
* @note Not all the listed fields are always needed, by switching off some
* not needed ChibiOS/RT subsystems it is possible to save RAM space by
* shrinking the \p Thread structure.
*/
struct Thread {
/** Next \p Thread in the threads list.*/
Thread *p_next;
/* End of the fields shared with the ThreadsList structure. */
/** Previous \p Thread in the threads list.*/
Thread *p_prev;
/* End of the fields shared with the ThreadsQueue structure. */
/** The thread priority.*/
tprio_t p_prio;
/* End of the fields shared with the ReadyList structure. */
/** Thread identifier. */
tid_t p_tid;
/** Current thread state.*/
tstate_t p_state;
/** Mode flags. */
tmode_t p_flags;
/** Machine dependent processor context.*/
Context p_ctx;
/*
* The following fields are merged in unions because they are all
* state-specific fields. This trick saves some extra space for each
* thread in the system.
*/
union {
/** Thread wakeup code (only valid when exiting the \p PRREADY state). */
msg_t p_rdymsg;
/** The thread exit code (only while in \p PREXIT state).*/
msg_t p_exitcode;
#ifdef CH_USE_SEMAPHORES
/** Semaphore where the thread is waiting on (only in \p PRWTSEM state). */
Semaphore *p_wtsemp;
#endif
#ifdef CH_USE_MUTEXES
/** Mutex where the thread is waiting on (only in \p PRWTMTX state). */
Mutex *p_wtmtxp;
#endif
#ifdef CH_USE_MESSAGES
/** Destination thread for message send (only in \p PRSNDMSG state). */
Thread *p_wtthdp;
#endif
#ifdef CH_USE_EVENTS
/** Enabled events mask (only while in \p PRWTEVENT state). */
eventmask_t p_ewmask;
#endif
#ifdef CH_USE_TRACE
/** Kernel object where the thread is waiting on. It is only valid when
the thread is some sleeping states. */
void *p_wtobjp;
#endif
};
/*
* Start of the optional fields.
*/
#ifdef CH_USE_WAITEXIT
/** The list of the threads waiting for this thread termination. */
ThreadsList p_waiting;
#endif
#ifdef CH_USE_EXIT_EVENT
/** The thread termination \p EventSource. */
EventSource p_exitesource;
#endif
#ifdef CH_USE_MESSAGES
ThreadsQueue p_msgqueue;
msg_t p_msg;
#endif
#ifdef CH_USE_EVENTS
/** Pending events mask. */
eventmask_t p_epending;
#endif
#ifdef CH_USE_MUTEXES
/** List of mutexes owned by this thread, \p NULL terminated. */
Mutex *p_mtxlist;
/** Thread's own, non-inherited, priority. */
tprio_t p_realprio;
#endif
#if defined(CH_USE_DYNAMIC) && defined(CH_USE_MEMPOOLS)
/** Memory Pool where the thread workspace is returned. */
void *p_mpool;
#endif
#ifdef CH_USE_THREAD_EXT
THREAD_EXT_FIELDS
#endif
};
/** Thread state: Ready to run, waiting on the ready list.*/
#define PRREADY 0
/** Thread state: Currently running. */
#define PRCURR 1
/** Thread state: Thread created in suspended state. */
#define PRSUSPENDED 2
/** Thread state: Waiting on a semaphore. */
#define PRWTSEM 3
/** Thread state: Waiting on a mutex. */
#define PRWTMTX 4
/** Thread state: Waiting in \p chThdSleep() or \p chThdSleepUntil(). */
#define PRSLEEP 5
/** Thread state: Waiting in \p chThdWait(). */
#define PRWAIT 6
/** Thread state: Waiting in \p chEvtWait(). */
#define PRWTEVENT 7
/** Thread state: Waiting in \p chMsgSend(). */
#define PRSNDMSG 8
/** Thread state: Waiting in \p chMsgWait(). */
#define PRWTMSG 9
/** Thread state: After termination.*/
#define PREXIT 10
/*
* Various flags into the thread p_flags field.
*/
#define P_MEM_MODE_MASK 3 /* Thread memory mode mask. */
#define P_MEM_MODE_STATIC 0 /* Thread memory mode: static. */
#define P_MEM_MODE_HEAP 1 /* Thread memory mode: heap. */
#define P_MEM_MODE_MEMPOOL 2 /* Thread memory mode: mempool. */
#define P_TERMINATE 4 /* Termination requested. */
#define P_SUSPENDED 8 /* Create suspended (old). */
/** Pseudo priority used by the ready list header, do not use.*/
#define NOPRIO 0
/** Idle thread priority.*/
#define IDLEPRIO 1
/** Lowest user priority.*/
#define LOWPRIO 2
/** Normal user priority.*/
#define NORMALPRIO 64
/** Highest user priority.*/
#define HIGHPRIO 127
/** Greatest possible priority.*/
#define ABSPRIO 255
/* Not an API, don't use into the application code.*/
Thread *init_thread(Thread *tp, tprio_t prio);
/** Thread function.*/
typedef msg_t (*tfunc_t)(void *);
/*
* Threads APIs.
*/
#ifdef __cplusplus
extern "C" {
#endif
Thread *chThdInit(void *workspace, size_t wsize,
tprio_t prio, tfunc_t pf, void *arg);
Thread *chThdCreateStatic(void *workspace, size_t wsize,
tprio_t prio, tfunc_t pf, void *arg);
#if defined(CH_USE_DYNAMIC) && defined(CH_USE_WAITEXIT) && defined(CH_USE_HEAP)
Thread *chThdCreateFromHeap(size_t wsize, tprio_t prio,
tfunc_t pf, void *arg);
#endif
#if defined(CH_USE_DYNAMIC) && defined(CH_USE_WAITEXIT) && defined(CH_USE_MEMPOOLS)
Thread *chThdCreateFromMemoryPool(MemoryPool *mp, tprio_t prio,
tfunc_t pf, void *arg);
#endif
Thread *chThdCreate(tprio_t prio, tmode_t mode, void *workspace,
size_t wsize, tfunc_t pf, void *arg);
void chThdSetPriority(tprio_t newprio);
Thread *chThdResume(Thread *tp);
void chThdSuspend(Thread **tpp);
void chThdTerminate(Thread *tp);
void chThdSleep(systime_t time);
void chThdExit(msg_t msg);
#ifdef CH_USE_WAITEXIT
msg_t chThdWait(Thread *tp);
#endif
#ifdef __cplusplus
}
#endif
/** Returns the pointer to the \p Thread currently in execution.*/
#define chThdSelf() currp
/** Returns the thread priority.*/
#define chThdGetPriority() (currp->p_prio)
/** Returns the pointer to the \p Thread local storage area, if any.*/
#define chThdLS() (void *)(currp + 1)
/** Verifies if the specified thread is in the \p PREXIT state.*/
#define chThdTerminated(tp) ((tp)->p_state == PREXIT)
/**
* Verifies if the current thread has a termination request pending.
*/
#define chThdShouldTerminate() (currp->p_flags & P_TERMINATE)
/**
* Returns the exit event source for the specified thread. The source is
* signaled when the thread terminates.
* @param tp the pointer to the thread
* @note When registering on a thread termination make sure the thread
* is still alive, if you do that after the thread termination
* then you would miss the event. There are two ways to ensure
* this:<br>
* <ul>
* <li>Create the thread suspended, register on the event source
* and then resume the thread (recommended).</li>
* <li>Create the thread with a lower priority then register on it.
* This does not work if the hardware is capable of multiple
* physical threads.</li>
* </ul>
* @note You dont need to unregister from a terminated thread because
* the event source becomes inactive.
* @note The function is available only if the \p CH_USE_EXIT_EVENT
* option is enabled in \p chconf.h.
* @deprecated \p THREAD_EXT_EXIT should be used, this functionality will be
* removed in version 1.0.0.
*/
#define chThdGetExitEventSource(tp) (&(tp)->p_exitesource)
/**
* Resumes a thread created with the \p P_SUSPENDED option or suspended with
* \p chThdSuspend().
* @param tp the pointer to the thread
*/
#define chThdResumeI(tp) chSchReadyI(tp)
/**
* Creates a new thread, simplified variant.
* @param prio the priority level for the new thread. Usually the threads are
* created with priority \p NORMALPRIO, priorities
* can range from \p LOWPRIO to \p HIGHPRIO.
* @param workspace pointer to a working area dedicated to the thread stack
* @param wsize size of the working area.
* @param pf the thread function
* @return the pointer to the \p Thread structure allocated for the
* thread into the working space area.
* @note A thread can terminate by calling \p chThdExit() or by simply
* returning from its main function.
* @deprecated Please use \p chThdCreateStatic() or \p chThdInit() instead,
* this function will be removed in version 1.0.0.
*/
#define chThdCreateFast(prio, workspace, wsize, pf) \
chThdCreateStatic(workspace, wsize, prio, pf, NULL)
/**
* Suspends the invoking thread until the system time arrives to the specified
* value.
*/
#define chThdSleepUntil(t) { \
chSysLock(); \
chSchGoSleepTimeoutS(PRSLEEP, \
(systime_t)((t) - chSysGetTime())); \
chSysUnlock(); \
}
#endif /* _THREADS_H_ */
/** @} */
|
