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. */
7 #include "internal_config.h"
13 #include <sys/syscall.h>
17 #include <linux/futex.h>
21 #include "xbt/parmap.h"
23 #include "xbt/function_types.h"
24 #include "xbt/dynar.h"
25 #include "xbt/xbt_os_thread.h"
26 #include "xbt/sysdep.h"
27 #include "simix/smx_private.h"
29 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_parmap, xbt, "parmap: parallel map");
34 } e_xbt_parmap_flag_t;
36 static void xbt_parmap_set_mode(xbt_parmap_t parmap, e_xbt_parmap_mode_t mode);
37 static void *xbt_parmap_worker_main(void *parmap);
38 static void xbt_parmap_work(xbt_parmap_t parmap);
40 static void xbt_parmap_posix_master_wait(xbt_parmap_t parmap);
41 static void xbt_parmap_posix_worker_signal(xbt_parmap_t parmap);
42 static void xbt_parmap_posix_master_signal(xbt_parmap_t parmap);
43 static void xbt_parmap_posix_worker_wait(xbt_parmap_t parmap, unsigned round);
46 static void xbt_parmap_futex_master_wait(xbt_parmap_t parmap);
47 static void xbt_parmap_futex_worker_signal(xbt_parmap_t parmap);
48 static void xbt_parmap_futex_master_signal(xbt_parmap_t parmap);
49 static void xbt_parmap_futex_worker_wait(xbt_parmap_t parmap, unsigned round);
50 static void futex_wait(unsigned *uaddr, unsigned val);
51 static void futex_wake(unsigned *uaddr, unsigned val);
54 static void xbt_parmap_busy_master_wait(xbt_parmap_t parmap);
55 static void xbt_parmap_busy_worker_signal(xbt_parmap_t parmap);
56 static void xbt_parmap_busy_master_signal(xbt_parmap_t parmap);
57 static void xbt_parmap_busy_worker_wait(xbt_parmap_t parmap, unsigned round);
60 static void xbt_parmap_mc_work(xbt_parmap_t parmap, int worker_id);
61 static void *xbt_parmap_mc_worker_main(void *arg);
65 * \brief Parallel map structure
67 typedef struct s_xbt_parmap {
68 e_xbt_parmap_flag_t status; /**< is the parmap active or being destroyed? */
69 unsigned work; /**< index of the current round */
70 unsigned thread_counter; /**< number of workers that have done the work */
72 unsigned int num_workers; /**< total number of worker threads including the controller */
73 xbt_os_thread_t *workers; /**< worker thread handlers */
74 void_f_pvoid_t fun; /**< function to run in parallel on each element of data */
75 xbt_dynar_t data; /**< parameters to pass to fun in parallel */
76 unsigned int index; /**< index of the next element of data to pick */
81 int_f_pvoid_pvoid_t snapshot_compare;
87 xbt_os_cond_t ready_cond;
88 xbt_os_mutex_t ready_mutex;
89 xbt_os_cond_t done_cond;
90 xbt_os_mutex_t done_mutex;
92 /* fields that depend on the synchronization mode */
93 e_xbt_parmap_mode_t mode; /**< synchronization mode */
94 void (*master_wait_f)(xbt_parmap_t); /**< wait for the workers to have done the work */
95 void (*worker_signal_f)(xbt_parmap_t); /**< signal the master that a worker has done the work */
96 void (*master_signal_f)(xbt_parmap_t); /**< wakes the workers threads to process tasks */
97 void (*worker_wait_f)(xbt_parmap_t, unsigned); /**< waits for more work */
101 * \brief Thread data transmission structure
103 typedef struct s_xbt_parmap_thread_data{
106 } s_xbt_parmap_thread_data_t;
108 typedef s_xbt_parmap_thread_data_t *xbt_parmap_thread_data_t;
111 * \brief Creates a parallel map object
112 * \param num_workers number of worker threads to create
113 * \param mode how to synchronize the worker threads
114 * \return the parmap created
116 xbt_parmap_t xbt_parmap_new(unsigned int num_workers, e_xbt_parmap_mode_t mode)
120 XBT_DEBUG("Create new parmap (%u workers)", num_workers);
122 /* Initialize the thread pool data structure */
123 xbt_parmap_t parmap = xbt_new0(s_xbt_parmap_t, 1);
124 parmap->workers = xbt_new(xbt_os_thread_t, num_workers);
126 parmap->num_workers = num_workers;
127 parmap->status = XBT_PARMAP_WORK;
128 xbt_parmap_set_mode(parmap, mode);
130 /* Create the pool of worker threads */
131 xbt_parmap_thread_data_t data;
132 parmap->workers[0] = NULL;
134 unsigned int core_bind = 0;
136 for (i = 1; i < num_workers; i++) {
137 data = xbt_new0(s_xbt_parmap_thread_data_t, 1);
138 data->parmap = parmap;
140 parmap->workers[i] = xbt_os_thread_create(NULL, xbt_parmap_worker_main,
143 xbt_os_thread_bind(parmap->workers[i], core_bind);
144 if(core_bind!=xbt_os_get_numcores()){
156 * \brief Creates a parallel map object
157 * \param num_workers number of worker threads to create
158 * \param mode how to synchronize the worker threads
159 * \return the parmap created
161 xbt_parmap_t xbt_parmap_mc_new(unsigned int num_workers, e_xbt_parmap_mode_t mode)
165 XBT_DEBUG("Create new parmap (%u workers)", num_workers);
167 /* Initialize the thread pool data structure */
168 xbt_parmap_t parmap = xbt_new0(s_xbt_parmap_t, 1);
169 parmap->workers = xbt_new(xbt_os_thread_t, num_workers);
171 parmap->num_workers = num_workers;
172 parmap->status = XBT_PARMAP_WORK;
173 xbt_parmap_set_mode(parmap, mode);
175 /* Create the pool of worker threads */
176 xbt_parmap_thread_data_t data;
177 parmap->workers[0] = NULL;
178 for (i = 1; i < num_workers; i++) {
179 data = xbt_new0(s_xbt_parmap_thread_data_t, 1);
180 data->parmap = parmap;
182 parmap->workers[i] = xbt_os_thread_create(NULL, xbt_parmap_mc_worker_main,
190 * \brief Destroys a parmap
191 * \param parmap the parmap to destroy
193 void xbt_parmap_destroy(xbt_parmap_t parmap)
199 parmap->status = XBT_PARMAP_DESTROY;
200 parmap->master_signal_f(parmap);
203 for (i = 1; i < parmap->num_workers; i++)
204 xbt_os_thread_join(parmap->workers[i], NULL);
206 xbt_os_cond_destroy(parmap->ready_cond);
207 xbt_os_mutex_destroy(parmap->ready_mutex);
208 xbt_os_cond_destroy(parmap->done_cond);
209 xbt_os_mutex_destroy(parmap->done_mutex);
211 xbt_free(parmap->workers);
216 * \brief Sets the synchronization mode of a parmap.
217 * \param parmap a parallel map object
218 * \param mode the synchronization mode
220 static void xbt_parmap_set_mode(xbt_parmap_t parmap, e_xbt_parmap_mode_t mode)
222 if (mode == XBT_PARMAP_DEFAULT) {
224 mode = XBT_PARMAP_FUTEX;
226 mode = XBT_PARMAP_POSIX;
233 case XBT_PARMAP_POSIX:
234 parmap->master_wait_f = xbt_parmap_posix_master_wait;
235 parmap->worker_signal_f = xbt_parmap_posix_worker_signal;
236 parmap->master_signal_f = xbt_parmap_posix_master_signal;
237 parmap->worker_wait_f = xbt_parmap_posix_worker_wait;
239 parmap->ready_cond = xbt_os_cond_init();
240 parmap->ready_mutex = xbt_os_mutex_init();
241 parmap->done_cond = xbt_os_cond_init();
242 parmap->done_mutex = xbt_os_mutex_init();
246 case XBT_PARMAP_FUTEX:
248 parmap->master_wait_f = xbt_parmap_futex_master_wait;
249 parmap->worker_signal_f = xbt_parmap_futex_worker_signal;
250 parmap->master_signal_f = xbt_parmap_futex_master_signal;
251 parmap->worker_wait_f = xbt_parmap_futex_worker_wait;
253 xbt_os_cond_destroy(parmap->ready_cond);
254 xbt_os_mutex_destroy(parmap->ready_mutex);
255 xbt_os_cond_destroy(parmap->done_cond);
256 xbt_os_mutex_destroy(parmap->done_mutex);
259 xbt_die("Futex is not available on this OS.");
262 case XBT_PARMAP_BUSY_WAIT:
263 parmap->master_wait_f = xbt_parmap_busy_master_wait;
264 parmap->worker_signal_f = xbt_parmap_busy_worker_signal;
265 parmap->master_signal_f = xbt_parmap_busy_master_signal;
266 parmap->worker_wait_f = xbt_parmap_busy_worker_wait;
268 xbt_os_cond_destroy(parmap->ready_cond);
269 xbt_os_mutex_destroy(parmap->ready_mutex);
270 xbt_os_cond_destroy(parmap->done_cond);
271 xbt_os_mutex_destroy(parmap->done_mutex);
274 case XBT_PARMAP_DEFAULT:
281 * \brief Applies a list of tasks in parallel.
282 * \param parmap a parallel map object
283 * \param fun the function to call in parallel
284 * \param data each element of this dynar will be passed as an argument to fun
286 void xbt_parmap_apply(xbt_parmap_t parmap, void_f_pvoid_t fun, xbt_dynar_t data)
288 /* Assign resources to worker threads (we are maestro here)*/
292 parmap->master_signal_f(parmap); // maestro runs futex_wait to wake all the minions (the working threads)
293 xbt_parmap_work(parmap); // maestro works with its minions
294 parmap->master_wait_f(parmap); // When there is no more work to do, then maestro waits for the last minion to stop
295 XBT_DEBUG("Job done"); // ... and proceeds
299 * \brief Returns a next task to process.
301 * Worker threads call this function to get more work.
303 * \return the next task to process, or NULL if there is no more work
305 void* xbt_parmap_next(xbt_parmap_t parmap)
307 unsigned int index = __sync_fetch_and_add(&parmap->index, 1);
308 if (index < xbt_dynar_length(parmap->data)) {
309 return xbt_dynar_get_as(parmap->data, index, void*);
314 static void xbt_parmap_work(xbt_parmap_t parmap)
317 while ((index = __sync_fetch_and_add(&parmap->index, 1))
318 < xbt_dynar_length(parmap->data))
319 parmap->fun(xbt_dynar_get_as(parmap->data, index, void*));
323 * \brief Main function of a worker thread.
324 * \param arg the parmap
326 static void *xbt_parmap_worker_main(void *arg)
328 xbt_parmap_thread_data_t data = (xbt_parmap_thread_data_t) arg;
329 xbt_parmap_t parmap = data->parmap;
331 smx_context_t context = SIMIX_context_new(NULL, 0, NULL, NULL, NULL);
332 SIMIX_context_set_current(context);
334 XBT_DEBUG("New worker thread created");
336 /* Worker's main loop */
338 parmap->worker_wait_f(parmap, ++round);
339 if (parmap->status == XBT_PARMAP_WORK) {
341 XBT_DEBUG("Worker %d got a job", data->worker_id);
343 xbt_parmap_work(parmap);
344 parmap->worker_signal_f(parmap);
346 XBT_DEBUG("Worker %d has finished", data->worker_id);
348 /* We are destroying the parmap */
350 SIMIX_context_free(context);
360 * \brief Applies a list of tasks in parallel.
361 * \param parmap a parallel map object
362 * \param fun the function to call in parallel
363 * \param data each element of this dynar will be passed as an argument to fun
365 int xbt_parmap_mc_apply(xbt_parmap_t parmap, int_f_pvoid_pvoid_t fun,
366 void* data, unsigned int length, void* ref_snapshot)
368 /* Assign resources to worker threads */
369 parmap->snapshot_compare = fun;
370 parmap->mc_data = data;
373 parmap->length = length;
374 parmap->ref_snapshot = ref_snapshot;
375 parmap->master_signal_f(parmap);
376 xbt_parmap_mc_work(parmap, 0);
377 parmap->master_wait_f(parmap);
378 XBT_DEBUG("Job done");
379 return parmap->finish;
382 static void xbt_parmap_mc_work(xbt_parmap_t parmap, int worker_id)
384 unsigned int data_size = (parmap->length / parmap->num_workers) +
385 ((parmap->length % parmap->num_workers) ? 1 :0);
386 void* start = (char*)parmap->mc_data + (data_size*worker_id*sizeof(void*));
387 void* end = MIN((char *)start + data_size* sizeof(void*), (char*)parmap->mc_data + parmap->length*sizeof(void*));
389 //XBT_CRITICAL("Worker %d : %p -> %p (%d)", worker_id, start, end, data_size);
391 while ( start < end && parmap->finish == -1) {
392 //XBT_CRITICAL("Starting with %p", start);
393 int res = parmap->snapshot_compare(*(void**)start, parmap->ref_snapshot);
394 start = (char *)start + sizeof(start);
397 parmap->finish = ((char*)start - (char*)parmap->mc_data) / sizeof(void*);
398 //XBT_CRITICAL("Find good one %p (%p)", start, parmap->mc_data);
405 * \brief Main function of a worker thread.
406 * \param arg the parmap
408 static void *xbt_parmap_mc_worker_main(void *arg)
410 xbt_parmap_thread_data_t data = (xbt_parmap_thread_data_t) arg;
411 xbt_parmap_t parmap = data->parmap;
413 /* smx_context_t context = SIMIX_context_new(NULL, 0, NULL, NULL, NULL); */
414 /* SIMIX_context_set_current(context); */
416 XBT_DEBUG("New worker thread created");
418 /* Worker's main loop */
420 parmap->worker_wait_f(parmap, ++round);
421 if (parmap->status == XBT_PARMAP_WORK) {
423 XBT_DEBUG("Worker %d got a job", data->worker_id);
425 xbt_parmap_mc_work(parmap, data->worker_id);
426 parmap->worker_signal_f(parmap);
428 XBT_DEBUG("Worker %d has finished", data->worker_id);
430 /* We are destroying the parmap */
440 static void futex_wait(unsigned *uaddr, unsigned val)
442 XBT_VERB("Waiting on futex %p", uaddr);
443 syscall(SYS_futex, uaddr, FUTEX_WAIT_PRIVATE, val, NULL, NULL, 0);
446 static void futex_wake(unsigned *uaddr, unsigned val)
448 XBT_VERB("Waking futex %p", uaddr);
449 syscall(SYS_futex, uaddr, FUTEX_WAKE_PRIVATE, val, NULL, NULL, 0);
454 * \brief Starts the parmap: waits for all workers to be ready and returns.
456 * This function is called by the controller thread.
458 * \param parmap a parmap
460 static void xbt_parmap_posix_master_wait(xbt_parmap_t parmap)
462 xbt_os_mutex_acquire(parmap->done_mutex);
463 if (parmap->thread_counter < parmap->num_workers) {
464 /* wait for all workers to be ready */
465 xbt_os_cond_wait(parmap->done_cond, parmap->done_mutex);
467 xbt_os_mutex_release(parmap->done_mutex);
471 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
473 * This function is called by all worker threads when they end (not including
476 * \param parmap a parmap
478 static void xbt_parmap_posix_worker_signal(xbt_parmap_t parmap)
480 xbt_os_mutex_acquire(parmap->done_mutex);
481 if (++parmap->thread_counter == parmap->num_workers) {
482 /* all workers have finished, wake the controller */
483 xbt_os_cond_signal(parmap->done_cond);
485 xbt_os_mutex_release(parmap->done_mutex);
489 * \brief Wakes all workers and waits for them to finish the tasks.
491 * This function is called by the controller thread.
493 * \param parmap a parmap
495 static void xbt_parmap_posix_master_signal(xbt_parmap_t parmap)
497 xbt_os_mutex_acquire(parmap->ready_mutex);
498 parmap->thread_counter = 1;
500 /* wake all workers */
501 xbt_os_cond_broadcast(parmap->ready_cond);
502 xbt_os_mutex_release(parmap->ready_mutex);
506 * \brief Waits for some work to process.
508 * This function is called by each worker thread (not including the controller)
509 * when it has no more work to do.
511 * \param parmap a parmap
512 * \param round the expected round number
514 static void xbt_parmap_posix_worker_wait(xbt_parmap_t parmap, unsigned round)
516 xbt_os_mutex_acquire(parmap->ready_mutex);
517 /* wait for more work */
518 if (parmap->work != round) {
519 xbt_os_cond_wait(parmap->ready_cond, parmap->ready_mutex);
521 xbt_os_mutex_release(parmap->ready_mutex);
526 * \brief Starts the parmap: waits for all workers to be ready and returns.
528 * This function is called by the controller thread.
530 * \param parmap a parmap
532 static void xbt_parmap_futex_master_wait(xbt_parmap_t parmap)
534 unsigned count = parmap->thread_counter;
535 while (count < parmap->num_workers) {
536 /* wait for all workers to be ready */
537 futex_wait(&parmap->thread_counter, count);
538 count = parmap->thread_counter;
543 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
545 * This function is called by all worker threads when they end (not including
548 * \param parmap a parmap
550 static void xbt_parmap_futex_worker_signal(xbt_parmap_t parmap)
552 unsigned count = __sync_add_and_fetch(&parmap->thread_counter, 1);
553 if (count == parmap->num_workers) {
554 /* all workers have finished, wake the controller */
555 futex_wake(&parmap->thread_counter, INT_MAX);
560 * \brief Wakes all workers and waits for them to finish the tasks.
562 * This function is called by the controller thread.
564 * \param parmap a parmap
566 static void xbt_parmap_futex_master_signal(xbt_parmap_t parmap)
568 parmap->thread_counter = 1;
569 __sync_add_and_fetch(&parmap->work, 1);
570 /* wake all workers */
571 futex_wake(&parmap->work, INT_MAX);
575 * \brief Waits for some work to process.
577 * This function is called by each worker thread (not including the controller)
578 * when it has no more work to do.
580 * \param parmap a parmap
581 * \param round the expected round number
583 static void xbt_parmap_futex_worker_wait(xbt_parmap_t parmap, unsigned round)
585 unsigned work = parmap->work;
586 /* wait for more work */
587 while (work != round) {
588 futex_wait(&parmap->work, work);
595 * \brief Starts the parmap: waits for all workers to be ready and returns.
597 * This function is called by the controller thread.
599 * \param parmap a parmap
601 static void xbt_parmap_busy_master_wait(xbt_parmap_t parmap)
603 while (parmap->thread_counter < parmap->num_workers) {
604 xbt_os_thread_yield();
609 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
611 * This function is called by all worker threads when they end.
613 * \param parmap a parmap
615 static void xbt_parmap_busy_worker_signal(xbt_parmap_t parmap)
617 __sync_add_and_fetch(&parmap->thread_counter, 1);
621 * \brief Wakes all workers and waits for them to finish the tasks.
623 * This function is called by the controller thread.
625 * \param parmap a parmap
627 static void xbt_parmap_busy_master_signal(xbt_parmap_t parmap)
629 parmap->thread_counter = 1;
630 __sync_add_and_fetch(&parmap->work, 1);
634 * \brief Waits for some work to process.
636 * This function is called by each worker thread (not including the controller)
637 * when it has no more work to do.
639 * \param parmap a parmap
640 * \param round the expected round number
642 static void xbt_parmap_busy_worker_wait(xbt_parmap_t parmap, unsigned round)
644 /* wait for more work */
645 while (parmap->work != round) {
646 xbt_os_thread_yield();