2 /* Copyright (c) 2007-2015. The SimGrid Team.
3 * All rights reserved. */
5 /* This program is free software; you can redistribute it and/or modify it
6 * under the terms of the license (GNU LGPL) which comes with this package. */
8 #include "src/surf/surf_interface.hpp"
9 #include "smx_private.h"
13 #include "src/simix/SynchroRaw.hpp"
15 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_synchro, simix,
16 "SIMIX Synchronization (mutex, semaphores and conditions)");
18 static smx_synchro_t SIMIX_synchro_wait(sg_host_t smx_host, double timeout);
19 static void _SIMIX_cond_wait(smx_cond_t cond, smx_mutex_t mutex, double timeout,
20 smx_process_t issuer, smx_simcall_t simcall);
21 static void _SIMIX_sem_wait(smx_sem_t sem, double timeout, smx_process_t issuer,
22 smx_simcall_t simcall);
24 /***************************** Raw synchronization *********************************/
26 static smx_synchro_t SIMIX_synchro_wait(sg_host_t smx_host, double timeout)
28 XBT_IN("(%p, %f)",smx_host,timeout);
30 simgrid::simix::Raw *sync = new simgrid::simix::Raw();
31 sync->sleep = surf_host_sleep(smx_host, timeout);
32 sync->sleep->setData(sync);
37 void SIMIX_synchro_stop_waiting(smx_process_t process, smx_simcall_t simcall)
39 XBT_IN("(%p, %p)",process,simcall);
40 switch (simcall->call) {
42 case SIMCALL_MUTEX_LOCK:
43 xbt_swag_remove(process, simcall_mutex_lock__get__mutex(simcall)->sleeping);
46 case SIMCALL_COND_WAIT:
47 xbt_swag_remove(process, simcall_cond_wait__get__cond(simcall)->sleeping);
50 case SIMCALL_COND_WAIT_TIMEOUT:
51 xbt_swag_remove(process, simcall_cond_wait_timeout__get__cond(simcall)->sleeping);
54 case SIMCALL_SEM_ACQUIRE:
55 xbt_swag_remove(process, simcall_sem_acquire__get__sem(simcall)->sleeping);
58 case SIMCALL_SEM_ACQUIRE_TIMEOUT:
59 xbt_swag_remove(process, simcall_sem_acquire_timeout__get__sem(simcall)->sleeping);
68 void SIMIX_synchro_finish(smx_synchro_t synchro)
70 XBT_IN("(%p)",synchro);
71 smx_simcall_t simcall = synchro->simcalls.front();
72 synchro->simcalls.pop_front();
74 switch (synchro->state) {
76 case SIMIX_SRC_TIMEOUT:
77 SMX_EXCEPTION(simcall->issuer, timeout_error, 0, "Synchro's wait timeout");
81 simcall->issuer->context->iwannadie = 1;
82 // SMX_EXCEPTION(simcall->issuer, host_error, 0, "Host failed");
90 SIMIX_synchro_stop_waiting(simcall->issuer, simcall);
91 simcall->issuer->waiting_synchro = nullptr;
93 SIMIX_simcall_answer(simcall);
96 /*********************************** Mutex ************************************/
101 Mutex::Mutex() : mutex_(this)
103 XBT_IN("(%p)", this);
104 // Useful to initialize sleeping swag:
105 simgrid::simix::Process p;
106 this->sleeping = xbt_swag_new(xbt_swag_offset(p, synchro_hookup));
112 XBT_IN("(%p)", this);
113 xbt_swag_free(this->sleeping);
117 void Mutex::lock(smx_process_t issuer)
119 XBT_IN("(%p; %p)", this, issuer);
120 /* FIXME: check where to validate the arguments */
121 smx_synchro_t synchro = nullptr;
124 /* FIXME: check if the host is active ? */
125 /* Somebody using the mutex, use a synchronization to get host failures */
126 synchro = SIMIX_synchro_wait(issuer->host, -1);
127 synchro->simcalls.push_back(&issuer->simcall);
128 issuer->waiting_synchro = synchro;
129 xbt_swag_insert(issuer, this->sleeping);
133 this->owner = issuer;
134 SIMIX_simcall_answer(&issuer->simcall);
139 /** Tries to lock the mutex for a process
141 * \param issuer the process that tries to acquire the mutex
142 * \return whether we managed to lock the mutex
144 bool Mutex::try_lock(smx_process_t issuer)
146 XBT_IN("(%p, %p)", this, issuer);
153 this->owner = issuer;
158 /** Unlock a mutex for a process
160 * Unlocks the mutex and gives it to a process waiting for it.
161 * If the unlocker is not the owner of the mutex nothing happens.
162 * If there are no process waiting, it sets the mutex as free.
164 void Mutex::unlock(smx_process_t issuer)
166 XBT_IN("(%p, %p)", this, issuer);
168 /* If the mutex is not owned by the issuer, that's not good */
169 if (issuer != this->owner)
170 THROWF(mismatch_error, 0, "Cannot release that mutex: it was locked by %s (pid:%d), not by you.",
171 SIMIX_process_get_name(this->owner),SIMIX_process_get_PID(this->owner));
173 if (xbt_swag_size(this->sleeping) > 0) {
174 /*process to wake up */
175 smx_process_t p = (smx_process_t) xbt_swag_extract(this->sleeping);
176 delete p->waiting_synchro;
177 p->waiting_synchro = nullptr;
179 SIMIX_simcall_answer(&p->simcall);
181 /* nobody to wake up */
182 this->locked = false;
183 this->owner = nullptr;
191 /** Increase the refcount for this mutex */
192 smx_mutex_t SIMIX_mutex_ref(smx_mutex_t mutex)
194 if (mutex != nullptr)
195 intrusive_ptr_add_ref(mutex);
199 /** Decrease the refcount for this mutex */
200 void SIMIX_mutex_unref(smx_mutex_t mutex)
202 if (mutex != nullptr)
203 intrusive_ptr_release(mutex);
206 smx_mutex_t simcall_HANDLER_mutex_init(smx_simcall_t simcall)
208 return new simgrid::simix::Mutex();
213 void simcall_HANDLER_mutex_lock(smx_simcall_t simcall, smx_mutex_t mutex)
215 mutex->lock(simcall->issuer);
218 int simcall_HANDLER_mutex_trylock(smx_simcall_t simcall, smx_mutex_t mutex)
220 return mutex->try_lock(simcall->issuer);
223 void simcall_HANDLER_mutex_unlock(smx_simcall_t simcall, smx_mutex_t mutex)
225 mutex->unlock(simcall->issuer);
228 /********************************* Condition **********************************/
231 * \brief Initialize a condition.
233 * Allocates and creates the data for the condition.
234 * It have to be called before the use of the condition.
235 * \return A condition
237 smx_cond_t SIMIX_cond_init(void)
240 simgrid::simix::Process p;
241 smx_cond_t cond = xbt_new0(s_smx_cond_t, 1);
242 cond->sleeping = xbt_swag_new(xbt_swag_offset(p, synchro_hookup));
243 cond->mutex = nullptr;
250 * \brief Handle a condition waiting simcall without timeouts
251 * \param simcall the simcall
253 void simcall_HANDLER_cond_wait(smx_simcall_t simcall, smx_cond_t cond, smx_mutex_t mutex)
255 XBT_IN("(%p)",simcall);
256 smx_process_t issuer = simcall->issuer;
258 _SIMIX_cond_wait(cond, mutex, -1, issuer, simcall);
263 * \brief Handle a condition waiting simcall with timeouts
264 * \param simcall the simcall
266 void simcall_HANDLER_cond_wait_timeout(smx_simcall_t simcall, smx_cond_t cond,
267 smx_mutex_t mutex, double timeout)
269 XBT_IN("(%p)",simcall);
270 smx_process_t issuer = simcall->issuer;
272 _SIMIX_cond_wait(cond, mutex, timeout, issuer, simcall);
277 static void _SIMIX_cond_wait(smx_cond_t cond, smx_mutex_t mutex, double timeout,
278 smx_process_t issuer, smx_simcall_t simcall)
280 XBT_IN("(%p, %p, %f, %p,%p)",cond,mutex,timeout,issuer,simcall);
281 smx_synchro_t synchro = nullptr;
283 XBT_DEBUG("Wait condition %p", cond);
285 /* If there is a mutex unlock it */
286 /* FIXME: what happens if the issuer is not the owner of the mutex? */
287 if (mutex != nullptr) {
289 mutex->unlock(issuer);
292 synchro = SIMIX_synchro_wait(issuer->host, timeout);
293 synchro->simcalls.push_front(simcall);
294 issuer->waiting_synchro = synchro;
295 xbt_swag_insert(simcall->issuer, cond->sleeping);
300 * \brief Signalizes a condition.
302 * Signalizes a condition and wakes up a sleeping process.
303 * If there are no process sleeping, no action is done.
304 * \param cond A condition
306 void SIMIX_cond_signal(smx_cond_t cond)
309 smx_process_t proc = nullptr;
310 smx_mutex_t mutex = nullptr;
311 smx_simcall_t simcall = nullptr;
313 XBT_DEBUG("Signal condition %p", cond);
315 /* If there are processes waiting for the condition choose one and try
316 to make it acquire the mutex */
317 if ((proc = (smx_process_t) xbt_swag_extract(cond->sleeping))) {
319 /* Destroy waiter's synchronization */
320 delete proc->waiting_synchro;
321 proc->waiting_synchro = nullptr;
323 /* Now transform the cond wait simcall into a mutex lock one */
324 simcall = &proc->simcall;
325 if(simcall->call == SIMCALL_COND_WAIT)
326 mutex = simcall_cond_wait__get__mutex(simcall);
328 mutex = simcall_cond_wait_timeout__get__mutex(simcall);
329 simcall->call = SIMCALL_MUTEX_LOCK;
331 simcall_HANDLER_mutex_lock(simcall, mutex);
337 * \brief Broadcasts a condition.
339 * Signal ALL processes waiting on a condition.
340 * If there are no process waiting, no action is done.
341 * \param cond A condition
343 void SIMIX_cond_broadcast(smx_cond_t cond)
346 XBT_DEBUG("Broadcast condition %p", cond);
348 /* Signal the condition until nobody is waiting on it */
349 while (xbt_swag_size(cond->sleeping)) {
350 SIMIX_cond_signal(cond);
355 smx_cond_t SIMIX_cond_ref(smx_cond_t cond)
358 intrusive_ptr_add_ref(cond);
362 void SIMIX_cond_unref(smx_cond_t cond)
365 XBT_DEBUG("Destroy condition %p", cond);
366 if (cond != nullptr) {
367 intrusive_ptr_release(cond);
373 void intrusive_ptr_add_ref(s_smx_cond_t *cond)
375 auto previous = (cond->refcount_)++;
376 xbt_assert(previous != 0);
380 void intrusive_ptr_release(s_smx_cond_t *cond)
382 auto count = --(cond->refcount_);
384 xbt_assert(xbt_swag_size(cond->sleeping) == 0,
385 "Cannot destroy conditional since someone is still using it");
387 xbt_swag_free(cond->sleeping);
392 /******************************** Semaphores **********************************/
393 #define SMX_SEM_NOLIMIT 99999
394 /** @brief Initialize a semaphore */
395 smx_sem_t SIMIX_sem_init(unsigned int value)
397 XBT_IN("(%u)",value);
398 simgrid::simix::Process p;
400 smx_sem_t sem = xbt_new0(s_smx_sem_t, 1);
401 sem->sleeping = xbt_swag_new(xbt_swag_offset(p, synchro_hookup));
407 /** @brief Destroys a semaphore */
408 void SIMIX_sem_destroy(smx_sem_t sem)
411 XBT_DEBUG("Destroy semaphore %p", sem);
412 if (sem != nullptr) {
413 xbt_assert(xbt_swag_size(sem->sleeping) == 0,
414 "Cannot destroy semaphore since someone is still using it");
415 xbt_swag_free(sem->sleeping);
421 void simcall_HANDLER_sem_release(smx_simcall_t simcall, smx_sem_t sem){
422 SIMIX_sem_release(sem);
424 /** @brief release the semaphore
426 * Unlock a process waiting on the semaphore.
427 * If no one was blocked, the semaphore capacity is increased by 1.
429 void SIMIX_sem_release(smx_sem_t sem)
434 XBT_DEBUG("Sem release semaphore %p", sem);
435 if ((proc = (smx_process_t) xbt_swag_extract(sem->sleeping))) {
436 delete proc->waiting_synchro;
437 proc->waiting_synchro = nullptr;
438 SIMIX_simcall_answer(&proc->simcall);
439 } else if (sem->value < SMX_SEM_NOLIMIT) {
445 /** @brief Returns true if acquiring this semaphore would block */
446 int SIMIX_sem_would_block(smx_sem_t sem)
450 return (sem->value <= 0);
453 int simcall_HANDLER_sem_get_capacity(smx_simcall_t simcall, smx_sem_t sem){
454 return SIMIX_sem_get_capacity(sem);
456 /** @brief Returns the current capacity of the semaphore */
457 int SIMIX_sem_get_capacity(smx_sem_t sem)
464 static void _SIMIX_sem_wait(smx_sem_t sem, double timeout, smx_process_t issuer,
465 smx_simcall_t simcall)
467 XBT_IN("(%p, %f, %p, %p)",sem,timeout,issuer,simcall);
468 smx_synchro_t synchro = nullptr;
470 XBT_DEBUG("Wait semaphore %p (timeout:%f)", sem, timeout);
471 if (sem->value <= 0) {
472 synchro = SIMIX_synchro_wait(issuer->host, timeout);
473 synchro->simcalls.push_front(simcall);
474 issuer->waiting_synchro = synchro;
475 xbt_swag_insert(issuer, sem->sleeping);
478 SIMIX_simcall_answer(simcall);
484 * \brief Handles a sem acquire simcall without timeout.
485 * \param simcall the simcall
487 void simcall_HANDLER_sem_acquire(smx_simcall_t simcall, smx_sem_t sem)
489 XBT_IN("(%p)",simcall);
490 _SIMIX_sem_wait(sem, -1, simcall->issuer, simcall);
495 * \brief Handles a sem acquire simcall with timeout.
496 * \param simcall the simcall
498 void simcall_HANDLER_sem_acquire_timeout(smx_simcall_t simcall, smx_sem_t sem, double timeout)
500 XBT_IN("(%p)",simcall);
501 _SIMIX_sem_wait(sem, timeout, simcall->issuer, simcall);
504 int simcall_HANDLER_sem_would_block(smx_simcall_t simcall, smx_sem_t sem) {
505 return SIMIX_sem_would_block(sem);