1 /* Copyright (c) 2004-2005, 2007, 2009-2014. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
9 #include "internal_config.h"
15 #include <sys/syscall.h>
19 #include <linux/futex.h>
23 #include "xbt/parmap.h"
25 #include "xbt/function_types.h"
26 #include "xbt/dynar.h"
27 #include "xbt/xbt_os_thread.h"
28 #include "xbt/sysdep.h"
29 #include "simix/smx_private.h"
31 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_parmap, xbt, "parmap: parallel map");
36 } e_xbt_parmap_flag_t;
38 static void xbt_parmap_set_mode(xbt_parmap_t parmap, e_xbt_parmap_mode_t mode);
39 static void *xbt_parmap_worker_main(void *parmap);
40 static void xbt_parmap_work(xbt_parmap_t parmap);
42 static void xbt_parmap_posix_master_wait(xbt_parmap_t parmap);
43 static void xbt_parmap_posix_worker_signal(xbt_parmap_t parmap);
44 static void xbt_parmap_posix_master_signal(xbt_parmap_t parmap);
45 static void xbt_parmap_posix_worker_wait(xbt_parmap_t parmap, unsigned round);
48 static void xbt_parmap_futex_master_wait(xbt_parmap_t parmap);
49 static void xbt_parmap_futex_worker_signal(xbt_parmap_t parmap);
50 static void xbt_parmap_futex_master_signal(xbt_parmap_t parmap);
51 static void xbt_parmap_futex_worker_wait(xbt_parmap_t parmap, unsigned round);
52 static void futex_wait(unsigned *uaddr, unsigned val);
53 static void futex_wake(unsigned *uaddr, unsigned val);
57 static void xbt_parmap_busy_master_wait(xbt_parmap_t parmap);
58 static void xbt_parmap_busy_worker_signal(xbt_parmap_t parmap);
59 static void xbt_parmap_busy_master_signal(xbt_parmap_t parmap);
60 static void xbt_parmap_busy_worker_wait(xbt_parmap_t parmap, unsigned round);
64 static void xbt_parmap_mc_work(xbt_parmap_t parmap, int worker_id);
65 static void *xbt_parmap_mc_worker_main(void *arg);
69 * \brief Parallel map structure
71 typedef struct s_xbt_parmap {
72 e_xbt_parmap_flag_t status; /**< is the parmap active or being destroyed? */
73 unsigned work; /**< index of the current round */
74 unsigned thread_counter; /**< number of workers that have done the work */
76 unsigned int num_workers; /**< total number of worker threads including the controller */
77 xbt_os_thread_t *workers; /**< worker thread handlers */
78 void_f_pvoid_t fun; /**< function to run in parallel on each element of data */
79 xbt_dynar_t data; /**< parameters to pass to fun in parallel */
80 std::atomic<unsigned int> index; /**< index of the next element of data to pick */
85 int_f_pvoid_pvoid_t snapshot_compare;
91 xbt_os_cond_t ready_cond;
92 xbt_os_mutex_t ready_mutex;
93 xbt_os_cond_t done_cond;
94 xbt_os_mutex_t done_mutex;
96 /* fields that depend on the synchronization mode */
97 e_xbt_parmap_mode_t mode; /**< synchronization mode */
98 void (*master_wait_f)(xbt_parmap_t); /**< wait for the workers to have done the work */
99 void (*worker_signal_f)(xbt_parmap_t); /**< signal the master that a worker has done the work */
100 void (*master_signal_f)(xbt_parmap_t); /**< wakes the workers threads to process tasks */
101 void (*worker_wait_f)(xbt_parmap_t, unsigned); /**< waits for more work */
105 * \brief Thread data transmission structure
107 typedef struct s_xbt_parmap_thread_data{
110 } s_xbt_parmap_thread_data_t;
112 typedef s_xbt_parmap_thread_data_t *xbt_parmap_thread_data_t;
115 * \brief Creates a parallel map object
116 * \param num_workers number of worker threads to create
117 * \param mode how to synchronize the worker threads
118 * \return the parmap created
120 xbt_parmap_t xbt_parmap_new(unsigned int num_workers, e_xbt_parmap_mode_t mode)
124 XBT_DEBUG("Create new parmap (%u workers)", num_workers);
126 /* Initialize the thread pool data structure */
127 xbt_parmap_t parmap = new s_xbt_parmap_t();
128 parmap->workers = xbt_new(xbt_os_thread_t, num_workers);
130 parmap->num_workers = num_workers;
131 parmap->status = XBT_PARMAP_WORK;
132 xbt_parmap_set_mode(parmap, mode);
134 /* Create the pool of worker threads */
135 xbt_parmap_thread_data_t data;
136 parmap->workers[0] = NULL;
138 unsigned int core_bind = 0;
140 for (i = 1; i < num_workers; i++) {
141 data = xbt_new0(s_xbt_parmap_thread_data_t, 1);
142 data->parmap = parmap;
144 parmap->workers[i] = xbt_os_thread_create(NULL, xbt_parmap_worker_main,
147 xbt_os_thread_bind(parmap->workers[i], core_bind);
148 if(core_bind!=xbt_os_get_numcores()){
160 * \brief Creates a parallel map object
161 * \param num_workers number of worker threads to create
162 * \param mode how to synchronize the worker threads
163 * \return the parmap created
165 xbt_parmap_t xbt_parmap_mc_new(unsigned int num_workers, e_xbt_parmap_mode_t mode)
169 XBT_DEBUG("Create new parmap (%u workers)", num_workers);
171 /* Initialize the thread pool data structure */
172 xbt_parmap_t parmap = new s_xbt_parmap_t();
173 parmap->workers = xbt_new(xbt_os_thread_t, num_workers);
175 parmap->num_workers = num_workers;
176 parmap->status = XBT_PARMAP_WORK;
177 xbt_parmap_set_mode(parmap, mode);
179 /* Create the pool of worker threads */
180 xbt_parmap_thread_data_t data;
181 parmap->workers[0] = NULL;
182 for (i = 1; i < num_workers; i++) {
183 data = xbt_new0(s_xbt_parmap_thread_data_t, 1);
184 data->parmap = parmap;
186 parmap->workers[i] = xbt_os_thread_create(NULL, xbt_parmap_mc_worker_main,
194 * \brief Destroys a parmap
195 * \param parmap the parmap to destroy
197 void xbt_parmap_destroy(xbt_parmap_t parmap)
203 parmap->status = XBT_PARMAP_DESTROY;
204 parmap->master_signal_f(parmap);
207 for (i = 1; i < parmap->num_workers; i++)
208 xbt_os_thread_join(parmap->workers[i], NULL);
210 xbt_os_cond_destroy(parmap->ready_cond);
211 xbt_os_mutex_destroy(parmap->ready_mutex);
212 xbt_os_cond_destroy(parmap->done_cond);
213 xbt_os_mutex_destroy(parmap->done_mutex);
215 xbt_free(parmap->workers);
220 * \brief Sets the synchronization mode of a parmap.
221 * \param parmap a parallel map object
222 * \param mode the synchronization mode
224 static void xbt_parmap_set_mode(xbt_parmap_t parmap, e_xbt_parmap_mode_t mode)
226 if (mode == XBT_PARMAP_DEFAULT) {
228 mode = XBT_PARMAP_FUTEX;
230 mode = XBT_PARMAP_POSIX;
237 case XBT_PARMAP_POSIX:
238 parmap->master_wait_f = xbt_parmap_posix_master_wait;
239 parmap->worker_signal_f = xbt_parmap_posix_worker_signal;
240 parmap->master_signal_f = xbt_parmap_posix_master_signal;
241 parmap->worker_wait_f = xbt_parmap_posix_worker_wait;
243 parmap->ready_cond = xbt_os_cond_init();
244 parmap->ready_mutex = xbt_os_mutex_init();
245 parmap->done_cond = xbt_os_cond_init();
246 parmap->done_mutex = xbt_os_mutex_init();
250 case XBT_PARMAP_FUTEX:
252 parmap->master_wait_f = xbt_parmap_futex_master_wait;
253 parmap->worker_signal_f = xbt_parmap_futex_worker_signal;
254 parmap->master_signal_f = xbt_parmap_futex_master_signal;
255 parmap->worker_wait_f = xbt_parmap_futex_worker_wait;
257 xbt_os_cond_destroy(parmap->ready_cond);
258 xbt_os_mutex_destroy(parmap->ready_mutex);
259 xbt_os_cond_destroy(parmap->done_cond);
260 xbt_os_mutex_destroy(parmap->done_mutex);
263 xbt_die("Futex is not available on this OS.");
266 case XBT_PARMAP_BUSY_WAIT:
268 parmap->master_wait_f = xbt_parmap_busy_master_wait;
269 parmap->worker_signal_f = xbt_parmap_busy_worker_signal;
270 parmap->master_signal_f = xbt_parmap_busy_master_signal;
271 parmap->worker_wait_f = xbt_parmap_busy_worker_wait;
273 xbt_os_cond_destroy(parmap->ready_cond);
274 xbt_os_mutex_destroy(parmap->ready_mutex);
275 xbt_os_cond_destroy(parmap->done_cond);
276 xbt_os_mutex_destroy(parmap->done_mutex);
279 xbt_die("Busy waiting not implemented on Windows yet.");
282 case XBT_PARMAP_DEFAULT:
289 * \brief Applies a list of tasks in parallel.
290 * \param parmap a parallel map object
291 * \param fun the function to call in parallel
292 * \param data each element of this dynar will be passed as an argument to fun
294 void xbt_parmap_apply(xbt_parmap_t parmap, void_f_pvoid_t fun, xbt_dynar_t data)
296 /* Assign resources to worker threads (we are maestro here)*/
300 parmap->master_signal_f(parmap); // maestro runs futex_wait to wake all the minions (the working threads)
301 xbt_parmap_work(parmap); // maestro works with its minions
302 parmap->master_wait_f(parmap); // When there is no more work to do, then maestro waits for the last minion to stop
303 XBT_DEBUG("Job done"); // ... and proceeds
307 * \brief Returns a next task to process.
309 * Worker threads call this function to get more work.
311 * \return the next task to process, or NULL if there is no more work
313 void* xbt_parmap_next(xbt_parmap_t parmap)
315 unsigned int index = parmap->index++;
316 if (index < xbt_dynar_length(parmap->data)) {
317 return xbt_dynar_get_as(parmap->data, index, void*);
322 static void xbt_parmap_work(xbt_parmap_t parmap)
325 while ((index = parmap->index++)
326 < xbt_dynar_length(parmap->data))
327 parmap->fun(xbt_dynar_get_as(parmap->data, index, void*));
331 * \brief Main function of a worker thread.
332 * \param arg the parmap
334 static void *xbt_parmap_worker_main(void *arg)
336 xbt_parmap_thread_data_t data = (xbt_parmap_thread_data_t) arg;
337 xbt_parmap_t parmap = data->parmap;
339 smx_context_t context = SIMIX_context_new(NULL, 0, NULL, NULL, NULL);
340 SIMIX_context_set_current(context);
342 XBT_DEBUG("New worker thread created");
344 /* Worker's main loop */
346 parmap->worker_wait_f(parmap, ++round);
347 if (parmap->status == XBT_PARMAP_WORK) {
349 XBT_DEBUG("Worker %d got a job", data->worker_id);
351 xbt_parmap_work(parmap);
352 parmap->worker_signal_f(parmap);
354 XBT_DEBUG("Worker %d has finished", data->worker_id);
356 /* We are destroying the parmap */
358 SIMIX_context_free(context);
368 * \brief Applies a list of tasks in parallel.
369 * \param parmap a parallel map object
370 * \param fun the function to call in parallel
371 * \param data each element of this dynar will be passed as an argument to fun
373 int xbt_parmap_mc_apply(xbt_parmap_t parmap, int_f_pvoid_pvoid_t fun,
374 void* data, unsigned int length, void* ref_snapshot)
376 /* Assign resources to worker threads */
377 parmap->snapshot_compare = fun;
378 parmap->mc_data = data;
381 parmap->length = length;
382 parmap->ref_snapshot = ref_snapshot;
383 parmap->master_signal_f(parmap);
384 xbt_parmap_mc_work(parmap, 0);
385 parmap->master_wait_f(parmap);
386 XBT_DEBUG("Job done");
387 return parmap->finish;
390 static void xbt_parmap_mc_work(xbt_parmap_t parmap, int worker_id)
392 unsigned int data_size = (parmap->length / parmap->num_workers) +
393 ((parmap->length % parmap->num_workers) ? 1 :0);
394 void* start = (char*)parmap->mc_data + (data_size*worker_id*sizeof(void*));
395 void* end = MIN((char *)start + data_size* sizeof(void*), (char*)parmap->mc_data + parmap->length*sizeof(void*));
397 //XBT_CRITICAL("Worker %d : %p -> %p (%d)", worker_id, start, end, data_size);
399 while ( start < end && parmap->finish == -1) {
400 //XBT_CRITICAL("Starting with %p", start);
401 int res = parmap->snapshot_compare(*(void**)start, parmap->ref_snapshot);
402 start = (char *)start + sizeof(start);
405 parmap->finish = ((char*)start - (char*)parmap->mc_data) / sizeof(void*);
406 //XBT_CRITICAL("Find good one %p (%p)", start, parmap->mc_data);
413 * \brief Main function of a worker thread.
414 * \param arg the parmap
416 static void *xbt_parmap_mc_worker_main(void *arg)
418 xbt_parmap_thread_data_t data = (xbt_parmap_thread_data_t) arg;
419 xbt_parmap_t parmap = data->parmap;
421 /* smx_context_t context = SIMIX_context_new(NULL, 0, NULL, NULL, NULL); */
422 /* SIMIX_context_set_current(context); */
424 XBT_DEBUG("New worker thread created");
426 /* Worker's main loop */
428 parmap->worker_wait_f(parmap, ++round);
429 if (parmap->status == XBT_PARMAP_WORK) {
431 XBT_DEBUG("Worker %d got a job", data->worker_id);
433 xbt_parmap_mc_work(parmap, data->worker_id);
434 parmap->worker_signal_f(parmap);
436 XBT_DEBUG("Worker %d has finished", data->worker_id);
438 /* We are destroying the parmap */
448 static void futex_wait(unsigned *uaddr, unsigned val)
450 XBT_VERB("Waiting on futex %p", uaddr);
451 syscall(SYS_futex, uaddr, FUTEX_WAIT_PRIVATE, val, NULL, NULL, 0);
454 static void futex_wake(unsigned *uaddr, unsigned val)
456 XBT_VERB("Waking futex %p", uaddr);
457 syscall(SYS_futex, uaddr, FUTEX_WAKE_PRIVATE, val, NULL, NULL, 0);
462 * \brief Starts the parmap: waits for all workers to be ready and returns.
464 * This function is called by the controller thread.
466 * \param parmap a parmap
468 static void xbt_parmap_posix_master_wait(xbt_parmap_t parmap)
470 xbt_os_mutex_acquire(parmap->done_mutex);
471 if (parmap->thread_counter < parmap->num_workers) {
472 /* wait for all workers to be ready */
473 xbt_os_cond_wait(parmap->done_cond, parmap->done_mutex);
475 xbt_os_mutex_release(parmap->done_mutex);
479 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
481 * This function is called by all worker threads when they end (not including
484 * \param parmap a parmap
486 static void xbt_parmap_posix_worker_signal(xbt_parmap_t parmap)
488 xbt_os_mutex_acquire(parmap->done_mutex);
489 if (++parmap->thread_counter == parmap->num_workers) {
490 /* all workers have finished, wake the controller */
491 xbt_os_cond_signal(parmap->done_cond);
493 xbt_os_mutex_release(parmap->done_mutex);
497 * \brief Wakes all workers and waits for them to finish the tasks.
499 * This function is called by the controller thread.
501 * \param parmap a parmap
503 static void xbt_parmap_posix_master_signal(xbt_parmap_t parmap)
505 xbt_os_mutex_acquire(parmap->ready_mutex);
506 parmap->thread_counter = 1;
508 /* wake all workers */
509 xbt_os_cond_broadcast(parmap->ready_cond);
510 xbt_os_mutex_release(parmap->ready_mutex);
514 * \brief Waits for some work to process.
516 * This function is called by each worker thread (not including the controller)
517 * when it has no more work to do.
519 * \param parmap a parmap
520 * \param round the expected round number
522 static void xbt_parmap_posix_worker_wait(xbt_parmap_t parmap, unsigned round)
524 xbt_os_mutex_acquire(parmap->ready_mutex);
525 /* wait for more work */
526 if (parmap->work != round) {
527 xbt_os_cond_wait(parmap->ready_cond, parmap->ready_mutex);
529 xbt_os_mutex_release(parmap->ready_mutex);
534 * \brief Starts the parmap: waits for all workers to be ready and returns.
536 * This function is called by the controller thread.
538 * \param parmap a parmap
540 static void xbt_parmap_futex_master_wait(xbt_parmap_t parmap)
542 unsigned count = parmap->thread_counter;
543 while (count < parmap->num_workers) {
544 /* wait for all workers to be ready */
545 futex_wait(&parmap->thread_counter, count);
546 count = parmap->thread_counter;
551 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
553 * This function is called by all worker threads when they end (not including
556 * \param parmap a parmap
558 static void xbt_parmap_futex_worker_signal(xbt_parmap_t parmap)
560 unsigned count = __sync_add_and_fetch(&parmap->thread_counter, 1);
561 if (count == parmap->num_workers) {
562 /* all workers have finished, wake the controller */
563 futex_wake(&parmap->thread_counter, INT_MAX);
568 * \brief Wakes all workers and waits for them to finish the tasks.
570 * This function is called by the controller thread.
572 * \param parmap a parmap
574 static void xbt_parmap_futex_master_signal(xbt_parmap_t parmap)
576 parmap->thread_counter = 1;
577 __sync_add_and_fetch(&parmap->work, 1);
578 /* wake all workers */
579 futex_wake(&parmap->work, INT_MAX);
583 * \brief Waits for some work to process.
585 * This function is called by each worker thread (not including the controller)
586 * when it has no more work to do.
588 * \param parmap a parmap
589 * \param round the expected round number
591 static void xbt_parmap_futex_worker_wait(xbt_parmap_t parmap, unsigned round)
593 unsigned work = parmap->work;
594 /* wait for more work */
595 while (work != round) {
596 futex_wait(&parmap->work, work);
604 * \brief Starts the parmap: waits for all workers to be ready and returns.
606 * This function is called by the controller thread.
608 * \param parmap a parmap
610 static void xbt_parmap_busy_master_wait(xbt_parmap_t parmap)
612 while (parmap->thread_counter < parmap->num_workers) {
613 xbt_os_thread_yield();
618 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
620 * This function is called by all worker threads when they end.
622 * \param parmap a parmap
624 static void xbt_parmap_busy_worker_signal(xbt_parmap_t parmap)
626 __sync_add_and_fetch(&parmap->thread_counter, 1);
630 * \brief Wakes all workers and waits for them to finish the tasks.
632 * This function is called by the controller thread.
634 * \param parmap a parmap
636 static void xbt_parmap_busy_master_signal(xbt_parmap_t parmap)
638 parmap->thread_counter = 1;
639 __sync_add_and_fetch(&parmap->work, 1);
643 * \brief Waits for some work to process.
645 * This function is called by each worker thread (not including the controller)
646 * when it has no more work to do.
648 * \param parmap a parmap
649 * \param round the expected round number
651 static void xbt_parmap_busy_worker_wait(xbt_parmap_t parmap, unsigned round)
653 /* wait for more work */
654 while (parmap->work != round) {
655 xbt_os_thread_yield();
658 #endif /* ! _MSC_VER */