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 "src/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 "src/simix/smx_private.h"
30 #include "src/simix/smx_private.hpp"
32 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_parmap, xbt, "parmap: parallel map");
37 } e_xbt_parmap_flag_t;
39 static void xbt_parmap_set_mode(xbt_parmap_t parmap, e_xbt_parmap_mode_t mode);
40 static void *xbt_parmap_worker_main(void *parmap);
41 static void xbt_parmap_work(xbt_parmap_t parmap);
43 static void xbt_parmap_posix_master_wait(xbt_parmap_t parmap);
44 static void xbt_parmap_posix_worker_signal(xbt_parmap_t parmap);
45 static void xbt_parmap_posix_master_signal(xbt_parmap_t parmap);
46 static void xbt_parmap_posix_worker_wait(xbt_parmap_t parmap, unsigned round);
49 static void xbt_parmap_futex_master_wait(xbt_parmap_t parmap);
50 static void xbt_parmap_futex_worker_signal(xbt_parmap_t parmap);
51 static void xbt_parmap_futex_master_signal(xbt_parmap_t parmap);
52 static void xbt_parmap_futex_worker_wait(xbt_parmap_t parmap, unsigned round);
53 static void futex_wait(unsigned *uaddr, unsigned val);
54 static void futex_wake(unsigned *uaddr, unsigned val);
58 static void xbt_parmap_busy_master_wait(xbt_parmap_t parmap);
59 static void xbt_parmap_busy_worker_signal(xbt_parmap_t parmap);
60 static void xbt_parmap_busy_master_signal(xbt_parmap_t parmap);
61 static void xbt_parmap_busy_worker_wait(xbt_parmap_t parmap, unsigned round);
65 static void xbt_parmap_mc_work(xbt_parmap_t parmap, int worker_id);
66 static void *xbt_parmap_mc_worker_main(void *arg);
70 * \brief Parallel map structure
72 typedef struct s_xbt_parmap {
73 e_xbt_parmap_flag_t status; /**< is the parmap active or being destroyed? */
74 unsigned work; /**< index of the current round */
75 unsigned thread_counter; /**< number of workers that have done the work */
77 unsigned int num_workers; /**< total number of worker threads including the controller */
78 xbt_os_thread_t *workers; /**< worker thread handlers */
79 void_f_pvoid_t fun; /**< function to run in parallel on each element of data */
80 xbt_dynar_t data; /**< parameters to pass to fun in parallel */
81 std::atomic<unsigned int> index; /**< index of the next element of data to pick */
86 int_f_pvoid_pvoid_t snapshot_compare;
92 xbt_os_cond_t ready_cond;
93 xbt_os_mutex_t ready_mutex;
94 xbt_os_cond_t done_cond;
95 xbt_os_mutex_t done_mutex;
97 /* fields that depend on the synchronization mode */
98 e_xbt_parmap_mode_t mode; /**< synchronization mode */
99 void (*master_wait_f)(xbt_parmap_t); /**< wait for the workers to have done the work */
100 void (*worker_signal_f)(xbt_parmap_t); /**< signal the master that a worker has done the work */
101 void (*master_signal_f)(xbt_parmap_t); /**< wakes the workers threads to process tasks */
102 void (*worker_wait_f)(xbt_parmap_t, unsigned); /**< waits for more work */
106 * \brief Thread data transmission structure
108 typedef struct s_xbt_parmap_thread_data{
111 } s_xbt_parmap_thread_data_t;
113 typedef s_xbt_parmap_thread_data_t *xbt_parmap_thread_data_t;
116 * \brief Creates a parallel map object
117 * \param num_workers number of worker threads to create
118 * \param mode how to synchronize the worker threads
119 * \return the parmap created
121 xbt_parmap_t xbt_parmap_new(unsigned int num_workers, e_xbt_parmap_mode_t mode)
125 XBT_DEBUG("Create new parmap (%u workers)", num_workers);
127 /* Initialize the thread pool data structure */
128 xbt_parmap_t parmap = new s_xbt_parmap_t();
129 parmap->workers = xbt_new(xbt_os_thread_t, num_workers);
131 parmap->num_workers = num_workers;
132 parmap->status = XBT_PARMAP_WORK;
133 xbt_parmap_set_mode(parmap, mode);
135 /* Create the pool of worker threads */
136 xbt_parmap_thread_data_t data;
137 parmap->workers[0] = NULL;
139 unsigned int core_bind = 0;
141 for (i = 1; i < num_workers; i++) {
142 data = xbt_new0(s_xbt_parmap_thread_data_t, 1);
143 data->parmap = parmap;
145 parmap->workers[i] = xbt_os_thread_create(NULL, xbt_parmap_worker_main,
148 xbt_os_thread_bind(parmap->workers[i], core_bind);
149 if(core_bind!=xbt_os_get_numcores()){
161 * \brief Creates a parallel map object
162 * \param num_workers number of worker threads to create
163 * \param mode how to synchronize the worker threads
164 * \return the parmap created
166 xbt_parmap_t xbt_parmap_mc_new(unsigned int num_workers, e_xbt_parmap_mode_t mode)
170 XBT_DEBUG("Create new parmap (%u workers)", num_workers);
172 /* Initialize the thread pool data structure */
173 xbt_parmap_t parmap = new s_xbt_parmap_t();
174 parmap->workers = xbt_new(xbt_os_thread_t, num_workers);
176 parmap->num_workers = num_workers;
177 parmap->status = XBT_PARMAP_WORK;
178 xbt_parmap_set_mode(parmap, mode);
180 /* Create the pool of worker threads */
181 xbt_parmap_thread_data_t data;
182 parmap->workers[0] = NULL;
183 for (i = 1; i < num_workers; i++) {
184 data = xbt_new0(s_xbt_parmap_thread_data_t, 1);
185 data->parmap = parmap;
187 parmap->workers[i] = xbt_os_thread_create(NULL, xbt_parmap_mc_worker_main,
195 * \brief Destroys a parmap
196 * \param parmap the parmap to destroy
198 void xbt_parmap_destroy(xbt_parmap_t parmap)
204 parmap->status = XBT_PARMAP_DESTROY;
205 parmap->master_signal_f(parmap);
208 for (i = 1; i < parmap->num_workers; i++)
209 xbt_os_thread_join(parmap->workers[i], NULL);
211 xbt_os_cond_destroy(parmap->ready_cond);
212 xbt_os_mutex_destroy(parmap->ready_mutex);
213 xbt_os_cond_destroy(parmap->done_cond);
214 xbt_os_mutex_destroy(parmap->done_mutex);
216 xbt_free(parmap->workers);
221 * \brief Sets the synchronization mode of a parmap.
222 * \param parmap a parallel map object
223 * \param mode the synchronization mode
225 static void xbt_parmap_set_mode(xbt_parmap_t parmap, e_xbt_parmap_mode_t mode)
227 if (mode == XBT_PARMAP_DEFAULT) {
229 mode = XBT_PARMAP_FUTEX;
231 mode = XBT_PARMAP_POSIX;
238 case XBT_PARMAP_POSIX:
239 parmap->master_wait_f = xbt_parmap_posix_master_wait;
240 parmap->worker_signal_f = xbt_parmap_posix_worker_signal;
241 parmap->master_signal_f = xbt_parmap_posix_master_signal;
242 parmap->worker_wait_f = xbt_parmap_posix_worker_wait;
244 parmap->ready_cond = xbt_os_cond_init();
245 parmap->ready_mutex = xbt_os_mutex_init();
246 parmap->done_cond = xbt_os_cond_init();
247 parmap->done_mutex = xbt_os_mutex_init();
251 case XBT_PARMAP_FUTEX:
253 parmap->master_wait_f = xbt_parmap_futex_master_wait;
254 parmap->worker_signal_f = xbt_parmap_futex_worker_signal;
255 parmap->master_signal_f = xbt_parmap_futex_master_signal;
256 parmap->worker_wait_f = xbt_parmap_futex_worker_wait;
258 xbt_os_cond_destroy(parmap->ready_cond);
259 xbt_os_mutex_destroy(parmap->ready_mutex);
260 xbt_os_cond_destroy(parmap->done_cond);
261 xbt_os_mutex_destroy(parmap->done_mutex);
264 xbt_die("Futex is not available on this OS.");
267 case XBT_PARMAP_BUSY_WAIT:
269 parmap->master_wait_f = xbt_parmap_busy_master_wait;
270 parmap->worker_signal_f = xbt_parmap_busy_worker_signal;
271 parmap->master_signal_f = xbt_parmap_busy_master_signal;
272 parmap->worker_wait_f = xbt_parmap_busy_worker_wait;
274 xbt_os_cond_destroy(parmap->ready_cond);
275 xbt_os_mutex_destroy(parmap->ready_mutex);
276 xbt_os_cond_destroy(parmap->done_cond);
277 xbt_os_mutex_destroy(parmap->done_mutex);
280 xbt_die("Busy waiting not implemented on Windows yet.");
283 case XBT_PARMAP_DEFAULT:
290 * \brief Applies a list of tasks in parallel.
291 * \param parmap a parallel map object
292 * \param fun the function to call in parallel
293 * \param data each element of this dynar will be passed as an argument to fun
295 void xbt_parmap_apply(xbt_parmap_t parmap, void_f_pvoid_t fun, xbt_dynar_t data)
297 /* Assign resources to worker threads (we are maestro here)*/
301 parmap->master_signal_f(parmap); // maestro runs futex_wait to wake all the minions (the working threads)
302 xbt_parmap_work(parmap); // maestro works with its minions
303 parmap->master_wait_f(parmap); // When there is no more work to do, then maestro waits for the last minion to stop
304 XBT_DEBUG("Job done"); // ... and proceeds
308 * \brief Returns a next task to process.
310 * Worker threads call this function to get more work.
312 * \return the next task to process, or NULL if there is no more work
314 void* xbt_parmap_next(xbt_parmap_t parmap)
316 unsigned int index = parmap->index++;
317 if (index < xbt_dynar_length(parmap->data)) {
318 return xbt_dynar_get_as(parmap->data, index, void*);
323 static void xbt_parmap_work(xbt_parmap_t parmap)
326 while ((index = parmap->index++)
327 < xbt_dynar_length(parmap->data))
328 parmap->fun(xbt_dynar_get_as(parmap->data, index, void*));
332 * \brief Main function of a worker thread.
333 * \param arg the parmap
335 static void *xbt_parmap_worker_main(void *arg)
337 xbt_parmap_thread_data_t data = (xbt_parmap_thread_data_t) arg;
338 xbt_parmap_t parmap = data->parmap;
340 smx_context_t context = SIMIX_context_new(NULL, 0, NULL, NULL, NULL);
341 SIMIX_context_set_current(context);
343 XBT_DEBUG("New worker thread created");
345 /* Worker's main loop */
347 parmap->worker_wait_f(parmap, ++round);
348 if (parmap->status == XBT_PARMAP_WORK) {
350 XBT_DEBUG("Worker %d got a job", data->worker_id);
352 xbt_parmap_work(parmap);
353 parmap->worker_signal_f(parmap);
355 XBT_DEBUG("Worker %d has finished", data->worker_id);
357 /* We are destroying the parmap */
359 SIMIX_context_free(context);
369 * \brief Applies a list of tasks in parallel.
370 * \param parmap a parallel map object
371 * \param fun the function to call in parallel
372 * \param data each element of this dynar will be passed as an argument to fun
374 int xbt_parmap_mc_apply(xbt_parmap_t parmap, int_f_pvoid_pvoid_t fun,
375 void* data, unsigned int length, void* ref_snapshot)
377 /* Assign resources to worker threads */
378 parmap->snapshot_compare = fun;
379 parmap->mc_data = data;
382 parmap->length = length;
383 parmap->ref_snapshot = ref_snapshot;
384 parmap->master_signal_f(parmap);
385 xbt_parmap_mc_work(parmap, 0);
386 parmap->master_wait_f(parmap);
387 XBT_DEBUG("Job done");
388 return parmap->finish;
391 static void xbt_parmap_mc_work(xbt_parmap_t parmap, int worker_id)
393 unsigned int data_size = (parmap->length / parmap->num_workers) +
394 ((parmap->length % parmap->num_workers) ? 1 :0);
395 void* start = (char*)parmap->mc_data + (data_size*worker_id*sizeof(void*));
396 void* end = MIN((char *)start + data_size* sizeof(void*), (char*)parmap->mc_data + parmap->length*sizeof(void*));
398 //XBT_CRITICAL("Worker %d : %p -> %p (%d)", worker_id, start, end, data_size);
400 while ( start < end && parmap->finish == -1) {
401 //XBT_CRITICAL("Starting with %p", start);
402 int res = parmap->snapshot_compare(*(void**)start, parmap->ref_snapshot);
403 start = (char *)start + sizeof(start);
406 parmap->finish = ((char*)start - (char*)parmap->mc_data) / sizeof(void*);
407 //XBT_CRITICAL("Find good one %p (%p)", start, parmap->mc_data);
414 * \brief Main function of a worker thread.
415 * \param arg the parmap
417 static void *xbt_parmap_mc_worker_main(void *arg)
419 xbt_parmap_thread_data_t data = (xbt_parmap_thread_data_t) arg;
420 xbt_parmap_t parmap = data->parmap;
422 /* smx_context_t context = SIMIX_context_new(NULL, 0, NULL, NULL, NULL); */
423 /* SIMIX_context_set_current(context); */
425 XBT_DEBUG("New worker thread created");
427 /* Worker's main loop */
429 parmap->worker_wait_f(parmap, ++round);
430 if (parmap->status == XBT_PARMAP_WORK) {
432 XBT_DEBUG("Worker %d got a job", data->worker_id);
434 xbt_parmap_mc_work(parmap, data->worker_id);
435 parmap->worker_signal_f(parmap);
437 XBT_DEBUG("Worker %d has finished", data->worker_id);
439 /* We are destroying the parmap */
449 static void futex_wait(unsigned *uaddr, unsigned val)
451 XBT_VERB("Waiting on futex %p", uaddr);
452 syscall(SYS_futex, uaddr, FUTEX_WAIT_PRIVATE, val, NULL, NULL, 0);
455 static void futex_wake(unsigned *uaddr, unsigned val)
457 XBT_VERB("Waking futex %p", uaddr);
458 syscall(SYS_futex, uaddr, FUTEX_WAKE_PRIVATE, val, NULL, NULL, 0);
463 * \brief Starts the parmap: waits for all workers to be ready and returns.
465 * This function is called by the controller thread.
467 * \param parmap a parmap
469 static void xbt_parmap_posix_master_wait(xbt_parmap_t parmap)
471 xbt_os_mutex_acquire(parmap->done_mutex);
472 if (parmap->thread_counter < parmap->num_workers) {
473 /* wait for all workers to be ready */
474 xbt_os_cond_wait(parmap->done_cond, parmap->done_mutex);
476 xbt_os_mutex_release(parmap->done_mutex);
480 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
482 * This function is called by all worker threads when they end (not including
485 * \param parmap a parmap
487 static void xbt_parmap_posix_worker_signal(xbt_parmap_t parmap)
489 xbt_os_mutex_acquire(parmap->done_mutex);
490 if (++parmap->thread_counter == parmap->num_workers) {
491 /* all workers have finished, wake the controller */
492 xbt_os_cond_signal(parmap->done_cond);
494 xbt_os_mutex_release(parmap->done_mutex);
498 * \brief Wakes all workers and waits for them to finish the tasks.
500 * This function is called by the controller thread.
502 * \param parmap a parmap
504 static void xbt_parmap_posix_master_signal(xbt_parmap_t parmap)
506 xbt_os_mutex_acquire(parmap->ready_mutex);
507 parmap->thread_counter = 1;
509 /* wake all workers */
510 xbt_os_cond_broadcast(parmap->ready_cond);
511 xbt_os_mutex_release(parmap->ready_mutex);
515 * \brief Waits for some work to process.
517 * This function is called by each worker thread (not including the controller)
518 * when it has no more work to do.
520 * \param parmap a parmap
521 * \param round the expected round number
523 static void xbt_parmap_posix_worker_wait(xbt_parmap_t parmap, unsigned round)
525 xbt_os_mutex_acquire(parmap->ready_mutex);
526 /* wait for more work */
527 if (parmap->work != round) {
528 xbt_os_cond_wait(parmap->ready_cond, parmap->ready_mutex);
530 xbt_os_mutex_release(parmap->ready_mutex);
535 * \brief Starts the parmap: waits for all workers to be ready and returns.
537 * This function is called by the controller thread.
539 * \param parmap a parmap
541 static void xbt_parmap_futex_master_wait(xbt_parmap_t parmap)
543 unsigned count = parmap->thread_counter;
544 while (count < parmap->num_workers) {
545 /* wait for all workers to be ready */
546 futex_wait(&parmap->thread_counter, count);
547 count = parmap->thread_counter;
552 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
554 * This function is called by all worker threads when they end (not including
557 * \param parmap a parmap
559 static void xbt_parmap_futex_worker_signal(xbt_parmap_t parmap)
561 unsigned count = __sync_add_and_fetch(&parmap->thread_counter, 1);
562 if (count == parmap->num_workers) {
563 /* all workers have finished, wake the controller */
564 futex_wake(&parmap->thread_counter, INT_MAX);
569 * \brief Wakes all workers and waits for them to finish the tasks.
571 * This function is called by the controller thread.
573 * \param parmap a parmap
575 static void xbt_parmap_futex_master_signal(xbt_parmap_t parmap)
577 parmap->thread_counter = 1;
578 __sync_add_and_fetch(&parmap->work, 1);
579 /* wake all workers */
580 futex_wake(&parmap->work, INT_MAX);
584 * \brief Waits for some work to process.
586 * This function is called by each worker thread (not including the controller)
587 * when it has no more work to do.
589 * \param parmap a parmap
590 * \param round the expected round number
592 static void xbt_parmap_futex_worker_wait(xbt_parmap_t parmap, unsigned round)
594 unsigned work = parmap->work;
595 /* wait for more work */
596 while (work != round) {
597 futex_wait(&parmap->work, work);
605 * \brief Starts the parmap: waits for all workers to be ready and returns.
607 * This function is called by the controller thread.
609 * \param parmap a parmap
611 static void xbt_parmap_busy_master_wait(xbt_parmap_t parmap)
613 while (parmap->thread_counter < parmap->num_workers) {
614 xbt_os_thread_yield();
619 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
621 * This function is called by all worker threads when they end.
623 * \param parmap a parmap
625 static void xbt_parmap_busy_worker_signal(xbt_parmap_t parmap)
627 __sync_add_and_fetch(&parmap->thread_counter, 1);
631 * \brief Wakes all workers and waits for them to finish the tasks.
633 * This function is called by the controller thread.
635 * \param parmap a parmap
637 static void xbt_parmap_busy_master_signal(xbt_parmap_t parmap)
639 parmap->thread_counter = 1;
640 __sync_add_and_fetch(&parmap->work, 1);
644 * \brief Waits for some work to process.
646 * This function is called by each worker thread (not including the controller)
647 * when it has no more work to do.
649 * \param parmap a parmap
650 * \param round the expected round number
652 static void xbt_parmap_busy_worker_wait(xbt_parmap_t parmap, unsigned round)
654 /* wait for more work */
655 while (parmap->work != round) {
656 xbt_os_thread_yield();
659 #endif /* ! _MSC_VER */