/* 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 . */ /** * @addtogroup Threads * @{ */ #include /* * Initializes a thread structure. */ void _InitThread(t_prio prio, t_tmode mode, Thread *tp) { static t_tid nextid = 0; tp->p_tid = nextid++; tp->p_flags = mode; tp->p_prio = prio; tp->p_rdymsg = RDY_OK; #ifdef CH_USE_MUTEXES tp->p_mtxlist = NULL; tp->p_realprio = prio; #endif #ifdef CH_USE_WAITEXIT list_init(&tp->p_waiting); #endif #ifdef CH_USE_MESSAGES fifo_init(&tp->p_msgqueue); #endif #ifdef CH_USE_EVENTS tp->p_epending = 0; #endif #ifdef CH_USE_EXIT_EVENT chEvtInit(&tp->p_exitesource); #endif } #ifdef CH_USE_DEBUG static void memfill(BYTE8 *p, ULONG32 n, BYTE8 v) { while (n) *p++ = v, n--; } #endif /** * Creates a new thread. * @param prio the priority level for the new thread. Usually the threads are * created with priority \p NORMALPRIO (128), priorities * can range from \p LOWPRIO (1) to \p HIGHPRIO * (255). * @param mode the creation option flags for the thread. The following options * can be OR'ed in this parameter:
* * @param workspace pointer to a working area dedicated to the thread stack * @param wsize size of the working area. * @param pf the thread function. Returning from this function automatically * terminates the thread. * @param 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. * @note A thread can terminate by calling \p chThdExit() or by simply * returning from its main function. */ Thread *chThdCreate(t_prio prio, t_tmode mode, void *workspace, t_size wsize, t_tfunc pf, void *arg) { Thread *tp = workspace; chDbgAssert((wsize > UserStackSize(0)) && (prio <= HIGHPRIO) && (workspace != NULL) && (pf != NULL), "chthreads.c, chThdCreate()"); #ifdef CH_USE_DEBUG memfill(workspace, wsize, MEM_FILL_PATTERN); #endif _InitThread(prio, mode, tp); SETUP_CONTEXT(workspace, wsize, pf, arg); #ifdef CH_USE_RESUME if (tp->p_flags & P_SUSPENDED) tp->p_state = PRSUSPENDED; else { #endif chSysLock(); chSchWakeupS(tp, RDY_OK); chSysUnlock(); #ifdef CH_USE_RESUME } #endif return tp; } /** * Changes the thread priority, reschedules if necessary. * @param newprio the new priority of the invoking thread */ void chThdSetPriority(t_prio newprio) { chDbgAssert(newprio <= HIGHPRIO, "chthreads.c, chThdSetPriority()") chSysLock(); #ifdef CH_USE_MUTEXES if (currp->p_prio != currp->p_realprio) { if (newprio > currp->p_prio) currp->p_prio = newprio; } else currp->p_prio = newprio; currp->p_realprio = newprio; #else currp->p_prio = newprio; #endif chSchRescheduleS(); chSysUnlock(); } #ifdef CH_USE_SUSPEND /** * Suspends the invoking thread. * * @param tpp pointer to a \p Thread pointer, the \p Thread pointer is set * to point to the suspended process before it enters the * \p PRSUSPENDED state, it is set to \p NULL after it is resumed. * This allows to implement a "test and resume" on the variable * into interrupt handlers. * @note The function is available only if the \p CH_USE_SUSPEND * option is enabled in \p chconf.h. */ void chThdSuspend(Thread **tpp) { chSysLock(); chDbgAssert(*tpp == NULL, "chthreads.c, chThdSuspend()"); *tpp = currp; chSchGoSleepS(PRSUSPENDED); *tpp = NULL; chSysUnlock(); } #endif /* CH_USE_SUSPEND */ #ifdef CH_USE_RESUME /** * Resumes a thread created with the \p P_SUSPENDED option or suspended with * \p chThdSuspend(). * @param tp the pointer to the thread * @note The function has no effect on threads in any other state than * \p PRSUSPENDED. * @note The function is available only if the \p CH_USE_RESUME * option is enabled in \p chconf.h. */ void chThdResume(Thread *tp) { chSysLock(); if ((tp)->p_state == PRSUSPENDED) chSchWakeupS((tp), RDY_OK); chSysUnlock(); } #endif #ifdef CH_USE_TERMINATE /** * Requests a thread termination. * @param tp the pointer to the thread * @note The thread is not termitated but a termination request is added to * its \p p_flags field. The thread can read this status by * invoking \p chThdShouldTerminate() and then terminate cleanly. */ void chThdTerminate(Thread *tp) { chSysLock(); tp->p_flags |= P_TERMINATE; chSysUnlock(); } #endif /** * Terminates the current thread by specifying an exit status code. * @param msg the thread exit code. The code can be retrieved by using * \p chThdWait(). */ void chThdExit(t_msg msg) { chSysLock(); currp->p_exitcode = msg; #ifdef CH_USE_WAITEXIT while (notempty(&currp->p_waiting)) chSchReadyI(list_remove(&currp->p_waiting), RDY_OK); #endif #ifdef CH_USE_EXIT_EVENT chEvtSendI(&currp->p_exitesource); #endif chSchGoSleepS(PREXIT); } #ifdef CH_USE_WAITEXIT /** * Blocks the execution of the invoking thread until the specified thread * terminates then the exit code is returned. * @param tp the pointer to the thread * @return the exit code * @note The function is available only if the \p CH_USE_WAITEXIT * option is enabled in \p chconf.h. */ t_msg chThdWait(Thread *tp) { t_msg msg; chSysLock(); if (tp->p_state != PREXIT) { list_insert(currp, &tp->p_waiting); chSchGoSleepS(PRWAIT); } msg = tp->p_exitcode; chSysUnlock(); return msg; } #endif /* CH_USE_WAITEXIT */ /** @} */ f='#n119'>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