aboutsummaryrefslogtreecommitdiffstats
path: root/os/kernel/src/chdynamic.c
blob: acd23c244936812941b4dbabe3e5dbbecdba5a5e (plain)
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
/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
                 2011 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/>.
*/

/**
 * @file    chdynamic.c
 * @brief   Dynamic threads code.
 *
 * @addtogroup dynamic_threads
 * @details Dynamic threads related APIs and services.
 * @{
 */

#include "ch.h"

#if CH_USE_DYNAMIC || defined(__DOXYGEN__)

/**
 * @brief   Adds a reference to a thread object.
 * @pre     The configuration option @p CH_USE_DYNAMIC must be enabled in order
 *          to use this function.
 *
 * @param[in] tp        pointer to the thread
 * @return              The same thread pointer passed as parameter
 *                      representing the new reference.
 *
 * @api
 */
Thread *chThdAddRef(Thread *tp) {

  chSysLock();
  chDbgAssert(tp->p_refs < 255, "chThdAddRef(), #1", "too many references");
  tp->p_refs++;
  chSysUnlock();
  return tp;
}

/**
 * @brief   Releases a reference to a thread object.
 * @details If the references counter reaches zero <b>and</b> the thread
 *          is in the @p THD_STATE_FINAL state then the thread's memory is
 *          returned to the proper allocator.
 * @pre     The configuration option @p CH_USE_DYNAMIC must be enabled in order
 *          to use this function.
 * @note    Static threads are not affected.
 *
 * @param[in] tp        pointer to the thread
 *
 * @api
 */
void chThdRelease(Thread *tp) {
  trefs_t refs;

  chSysLock();
  chDbgAssert(tp->p_refs > 0, "chThdRelease(), #1", "not referenced");
  refs = --tp->p_refs;
  chSysUnlock();

  /* If the references counter reaches zero and the thread is in its
     terminated state then the memory can be returned to the proper
     allocator. Of course static threads are not affected.*/
  if ((refs == 0) && (tp->p_state == THD_STATE_FINAL)) {
    switch (tp->p_flags & THD_MEM_MODE_MASK) {
#if CH_USE_HEAP
    case THD_MEM_MODE_HEAP:
#if CH_USE_REGISTRY
      REG_REMOVE(tp);
#endif
      chHeapFree(tp);
      break;
#endif
#if CH_USE_MEMPOOLS
    case THD_MEM_MODE_MEMPOOL:
#if CH_USE_REGISTRY
      REG_REMOVE(tp);
#endif
      chPoolFree(tp->p_mpool, tp);
      break;
#endif
    }
  }
}

#if CH_USE_HEAP || defined(__DOXYGEN__)
/**
 * @brief   Creates a new thread allocating the memory from the heap.
 * @pre     The configuration options @p CH_USE_DYNAMIC and @p CH_USE_HEAP
 *          must be enabled in order to use this function.
 * @note    A thread can terminate by calling @p chThdExit() or by simply
 *          returning from its main function.
 * @note    The memory allocated for the thread is not released when the thread
 *          terminates but when a @p chThdWait() is performed.
 *
 * @param[in] heapp     heap from which allocate the memory or @p NULL for the
 *                      default heap
 * @param[in] size      size of the working area to be allocated
 * @param[in] prio      the priority level for the new thread
 * @param[in] pf        the thread function
 * @param[in] arg       an argument passed to the thread function. It can be
 *                      @p NULL.
 * @return              The pointer to the @p Thread structure allocated for
 *                      the thread into the working space area.
 * @retval NULL         if the memory cannot be allocated.
 *
 * @api
 */
Thread *chThdCreateFromHeap(MemoryHeap *heapp, size_t size,
                            tprio_t prio, tfunc_t pf, void *arg) {
  void *wsp;
  Thread *tp;

  wsp = chHeapAlloc(heapp, size);
  if (wsp == NULL)
    return NULL;
  
#if CH_DBG_FILL_THREADS
  _thread_memfill((uint8_t *)wsp,
                  (uint8_t *)wsp + sizeof(Thread),
                  THREAD_FILL_VALUE);
  _thread_memfill((uint8_t *)wsp + sizeof(Thread),
                  (uint8_t *)wsp + size,
                  STACK_FILL_VALUE);
#endif
  
  chSysLock();
  tp = chThdCreateI(wsp, size, prio, pf, arg);
  tp->p_flags = THD_MEM_MODE_HEAP;
  chSchWakeupS(tp, RDY_OK);
  chSysUnlock();
  return tp;
}
#endif /* CH_USE_HEAP */

#if CH_USE_MEMPOOLS || defined(__DOXYGEN__)
/**
 * @brief   Creates a new thread allocating the memory from the specified
 *          memory pool.
 * @pre     The configuration options @p CH_USE_DYNAMIC and @p CH_USE_MEMPOOLS
 *          must be enabled in order to use this function.
 * @note    A thread can terminate by calling @p chThdExit() or by simply
 *          returning from its main function.
 * @note    The memory allocated for the thread is not released when the thread
 *          terminates but when a @p chThdWait() is performed.
 *
 * @param[in] mp        pointer to the memory pool object
 * @param[in] prio      the priority level for the new thread
 * @param[in] pf        the thread function
 * @param[in] arg       an argument passed to the thread function. It can be
 *                      @p NULL.
 * @return              The pointer to the @p Thread structure allocated for
 *                      the thread into the working space area.
 * @retval  NULL        if the memory pool is empty.
 *
 * @api
 */
Thread *chThdCreateFromMemoryPool(MemoryPool *mp, tprio_t prio,
                                  tfunc_t pf, void *arg) {
  void *wsp;
  Thread *tp;

  chDbgCheck(mp != NULL, "chThdCreateFromMemoryPool");

  wsp = chPoolAlloc(mp);
  if (wsp == NULL)
    return NULL;
  
#if CH_DBG_FILL_THREADS
  _thread_memfill((uint8_t *)wsp,
                  (uint8_t *)wsp + sizeof(Thread),
                  THREAD_FILL_VALUE);
  _thread_memfill((uint8_t *)wsp + sizeof(Thread),
                  (uint8_t *)wsp + mp->mp_object_size,
                  STACK_FILL_VALUE);
#endif

  chSysLock();
  tp = chThdCreateI(wsp, mp->mp_object_size, prio, pf, arg);
  tp->p_flags = THD_MEM_MODE_MEMPOOL;
  tp->p_mpool = mp;
  chSchWakeupS(tp, RDY_OK);
  chSysUnlock();
  return tp;
}
#endif /* CH_USE_MEMPOOLS */

#endif /* CH_USE_DYNAMIC */

/** @} */