1 /* Copyright (c) 2004-2013. 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 "msg_private.h"
8 #include "simix/smx_private.h"
9 #include "xbt/sysdep.h"
12 /** @addtogroup m_task_management
15 * Since most scheduling algorithms rely on a concept of task
16 * that can be either <em>computed</em> locally or
17 * <em>transferred</em> on another processor, it seems to be the
18 * right level of abstraction for our purposes. A <em>task</em>
19 * may then be defined by a <em>computing amount</em>, a
20 * <em>message size</em> and some <em>private data</em>.
23 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(msg_task, msg,
24 "Logging specific to MSG (task)");
26 /********************************* Task **************************************/
27 /** \ingroup m_task_management
28 * \brief Creates a new #msg_task_t.
30 * A constructor for #msg_task_t taking four arguments and returning the
32 * \param name a name for the object. It is for user-level information
34 * \param compute_duration a value of the processing amount (in flop)
35 needed to process this new task. If 0, then it cannot be executed with
36 MSG_task_execute(). This value has to be >=0.
37 * \param message_size a value of the amount of data (in bytes) needed to
38 transfer this new task. If 0, then it cannot be transfered with
39 MSG_task_send() and MSG_task_recv(). This value has to be >=0.
40 * \param data a pointer to any data may want to attach to the new
41 object. It is for user-level information and can be NULL. It can
42 be retrieved with the function \ref MSG_task_get_data.
44 * \return The new corresponding object.
46 msg_task_t MSG_task_create(const char *name, double compute_duration,
47 double message_size, void *data)
49 msg_task_t task = xbt_new(s_msg_task_t, 1);
50 simdata_task_t simdata = xbt_new(s_simdata_task_t, 1);
51 task->simdata = simdata;
54 task->name = xbt_strdup(name);
58 simdata->compute = NULL;
60 simdata->message_size = message_size;
61 simdata->computation_amount = compute_duration;
62 simdata->sender = NULL;
63 simdata->receiver = NULL;
64 simdata->source = NULL;
65 simdata->priority = 1.0;
67 simdata->affinity_mask_db = xbt_dict_new_homogeneous(NULL);
72 simdata->host_list = NULL;
73 simdata->comp_amount = NULL;
74 simdata->comm_amount = NULL;
76 TRACE_msg_task_create(task);
82 /** \ingroup m_task_management
83 * \brief Creates a new #msg_task_t (a parallel one....).
85 * A constructor for #msg_task_t taking six arguments and returning the
87 * \param name a name for the object. It is for user-level information
89 * \param host_nb the number of hosts implied in the parallel task.
90 * \param host_list an array of \p host_nb msg_host_t.
91 * \param computation_amount an array of \p host_nb
92 doubles. computation_amount[i] is the total number of operations
93 that have to be performed on host_list[i].
94 * \param communication_amount an array of \p host_nb* \p host_nb doubles.
95 * \param data a pointer to any data may want to attach to the new
96 object. It is for user-level information and can be NULL. It can
97 be retrieved with the function \ref MSG_task_get_data.
99 * \return The new corresponding object.
102 MSG_parallel_task_create(const char *name, int host_nb,
103 const msg_host_t * host_list,
104 double *computation_amount,
105 double *communication_amount, void *data)
107 msg_task_t task = MSG_task_create(name, 0, 0, data);
108 simdata_task_t simdata = task->simdata;
111 /* Simulator Data specific to parallel tasks */
112 simdata->host_nb = host_nb;
113 simdata->host_list = xbt_new0(smx_host_t, host_nb);
114 simdata->comp_amount = computation_amount;
115 simdata->comm_amount = communication_amount;
117 for (i = 0; i < host_nb; i++)
118 simdata->host_list[i] = host_list[i];
123 /*************** Begin GPU ***************/
124 /** \ingroup m_task_management
125 * \brief Creates a new #msg_gpu_task_t.
127 * A constructor for #msg_gpu_task_t taking four arguments and returning
128 a pointer to the new created GPU task.
130 * \param name a name for the object. It is for user-level information
133 * \param compute_duration a value of the processing amount (in flop)
134 needed to process this new task. If 0, then it cannot be executed with
135 MSG_gpu_task_execute(). This value has to be >=0.
137 * \param dispatch_latency time in seconds to load this task on the GPU
139 * \param collect_latency time in seconds to transfer result from the GPU
140 back to the CPU (host) when done
142 * \see msg_gpu_task_t
143 * \return The new corresponding object.
145 msg_gpu_task_t MSG_gpu_task_create(const char *name, double compute_duration,
146 double dispatch_latency, double collect_latency)
148 msg_gpu_task_t task = xbt_new(s_msg_gpu_task_t, 1);
149 simdata_gpu_task_t simdata = xbt_new(s_simdata_gpu_task_t, 1);
150 task->simdata = simdata;
152 task->name = xbt_strdup(name);
155 simdata->computation_amount = compute_duration;
156 simdata->dispatch_latency = dispatch_latency;
157 simdata->collect_latency = collect_latency;
161 /* TRACE_msg_gpu_task_create(task); */
166 /*************** End GPU ***************/
168 /** \ingroup m_task_management
169 * \brief Return the user data of a #msg_task_t.
171 * This function checks whether \a task is a valid pointer or not and return
172 the user data associated to \a task if it is possible.
174 void *MSG_task_get_data(msg_task_t task)
176 xbt_assert((task != NULL), "Invalid parameter");
181 /** \ingroup m_task_management
182 * \brief Sets the user data of a #msg_task_t.
184 * This function allows to associate a new pointer to
185 the user data associated of \a task.
187 void MSG_task_set_data(msg_task_t task, void *data)
189 xbt_assert((task != NULL), "Invalid parameter");
194 /** \ingroup m_task_management
195 * \brief Sets a function to be called when a task has just been copied.
196 * \param callback a callback function
198 void MSG_task_set_copy_callback(void (*callback)
199 (msg_task_t task, msg_process_t sender, msg_process_t receiver)) {
201 msg_global->task_copy_callback = callback;
204 SIMIX_comm_set_copy_data_callback(MSG_comm_copy_data_from_SIMIX);
207 SIMIX_comm_set_copy_data_callback(SIMIX_comm_copy_pointer_callback);
211 /** \ingroup m_task_management
212 * \brief Return the sender of a #msg_task_t.
214 * This functions returns the #msg_process_t which sent this task
216 msg_process_t MSG_task_get_sender(msg_task_t task)
218 xbt_assert(task, "Invalid parameters");
219 return ((simdata_task_t) task->simdata)->sender;
222 /** \ingroup m_task_management
223 * \brief Return the source of a #msg_task_t.
225 * This functions returns the #msg_host_t from which this task was sent
227 msg_host_t MSG_task_get_source(msg_task_t task)
229 xbt_assert(task, "Invalid parameters");
230 return ((simdata_task_t) task->simdata)->source;
233 /** \ingroup m_task_management
234 * \brief Return the name of a #msg_task_t.
236 * This functions returns the name of a #msg_task_t as specified on creation
238 const char *MSG_task_get_name(msg_task_t task)
240 xbt_assert(task, "Invalid parameters");
244 /** \ingroup m_task_management
245 * \brief Sets the name of a #msg_task_t.
247 * This functions allows to associate a name to a task
249 void MSG_task_set_name(msg_task_t task, const char *name)
251 xbt_assert(task, "Invalid parameters");
252 task->name = xbt_strdup(name);
255 /** \ingroup m_task_management
256 * \brief Destroy a #msg_task_t.
258 * Destructor for #msg_task_t. Note that you should free user data, if any, \b
259 * before calling this function.
261 * Only the process that owns the task can destroy it.
262 * The owner changes after a successful send.
263 * If a task is successfully sent, the receiver becomes the owner and is
264 * supposed to destroy it. The sender should not use it anymore.
265 * If the task failed to be sent, the sender remains the owner of the task.
267 msg_error_t MSG_task_destroy(msg_task_t task)
269 smx_action_t action = NULL;
270 xbt_assert((task != NULL), "Invalid parameter");
272 if (task->simdata->isused) {
273 /* the task is being sent or executed: cancel it first */
274 MSG_task_cancel(task);
277 TRACE_msg_task_destroy(task);
280 xbt_free(task->name);
282 action = task->simdata->compute;
284 simcall_host_execution_destroy(action);
286 /* parallel tasks only */
287 xbt_free(task->simdata->host_list);
289 xbt_dict_free(&task->simdata->affinity_mask_db);
291 /* free main structures */
292 xbt_free(task->simdata);
299 /** \ingroup m_task_usage
300 * \brief Cancel a #msg_task_t.
301 * \param task the task to cancel. If it was executed or transfered, it
302 stops the process that were working on it.
304 msg_error_t MSG_task_cancel(msg_task_t task)
306 xbt_assert((task != NULL), "Cannot cancel a NULL task");
308 if (task->simdata->compute) {
309 simcall_host_execution_cancel(task->simdata->compute);
311 else if (task->simdata->comm) {
312 simcall_comm_cancel(task->simdata->comm);
313 task->simdata->isused = 0;
318 /** \ingroup m_task_management
319 * \brief Returns the computation amount needed to process a task #msg_task_t.
321 * Once a task has been processed, this amount is set to 0. If you want, you
322 * can reset this value with #MSG_task_set_compute_duration before restarting the task.
324 double MSG_task_get_compute_duration(msg_task_t task)
326 xbt_assert((task != NULL)
327 && (task->simdata != NULL), "Invalid parameter");
329 return task->simdata->computation_amount;
333 /** \ingroup m_task_management
334 * \brief set the computation amount needed to process a task #msg_task_t.
336 * \warning If the computation is ongoing (already started and not finished),
337 * it is not modified by this call. And the termination of the ongoing task with
338 * set the computation_amount to zero, overriding any value set during the
342 void MSG_task_set_compute_duration(msg_task_t task,
343 double computation_amount)
345 xbt_assert(task, "Invalid parameter");
346 task->simdata->computation_amount = computation_amount;
350 /** \ingroup m_task_management
351 * \brief set the amount data attached with a task #msg_task_t.
353 * \warning If the transfer is ongoing (already started and not finished),
354 * it is not modified by this call.
357 void MSG_task_set_data_size(msg_task_t task,
360 xbt_assert(task, "Invalid parameter");
361 task->simdata->message_size = data_size;
367 /** \ingroup m_task_management
368 * \brief Returns the remaining computation amount of a task #msg_task_t.
370 * If the task is ongoing, this call retrieves the remaining amount of work.
371 * If it is not ongoing, it returns the total amount of work that will be
372 * executed when the task starts.
374 double MSG_task_get_remaining_computation(msg_task_t task)
376 xbt_assert((task != NULL)
377 && (task->simdata != NULL), "Invalid parameter");
379 if (task->simdata->compute) {
380 return simcall_host_execution_get_remains(task->simdata->compute);
382 return task->simdata->computation_amount;
386 /** \ingroup m_task_management
387 * \brief Returns the total amount received by a task #msg_task_t.
388 * If the communication does not exist it will return 0.
389 * So, if the communication has FINISHED or FAILED it returns
392 double MSG_task_get_remaining_communication(msg_task_t task)
394 xbt_assert((task != NULL)
395 && (task->simdata != NULL), "Invalid parameter");
396 XBT_DEBUG("calling simcall_communication_get_remains(%p)",
397 task->simdata->comm);
398 return simcall_comm_get_remains(task->simdata->comm);
401 #ifdef HAVE_LATENCY_BOUND_TRACKING
402 /** \ingroup m_task_management
403 * \brief Return 1 if communication task is limited by latency, 0 otherwise
406 int MSG_task_is_latency_bounded(msg_task_t task)
408 xbt_assert((task != NULL)
409 && (task->simdata != NULL), "Invalid parameter");
410 XBT_DEBUG("calling simcall_communication_is_latency_bounded(%p)",
411 task->simdata->comm);
412 return simcall_comm_is_latency_bounded(task->simdata->comm);
416 /** \ingroup m_task_management
417 * \brief Returns the size of the data attached to a task #msg_task_t.
420 double MSG_task_get_data_size(msg_task_t task)
422 xbt_assert((task != NULL)
423 && (task->simdata != NULL), "Invalid parameter");
425 return task->simdata->message_size;
430 /** \ingroup m_task_management
431 * \brief Changes the priority of a computation task. This priority doesn't affect
432 * the transfer rate. A priority of 2 will make a task receive two times more
433 * cpu power than the other ones.
436 void MSG_task_set_priority(msg_task_t task, double priority)
438 xbt_assert((task != NULL)
439 && (task->simdata != NULL), "Invalid parameter");
441 task->simdata->priority = 1 / priority;
442 if (task->simdata->compute)
443 simcall_host_execution_set_priority(task->simdata->compute,
444 task->simdata->priority);
448 /** \ingroup m_task_management
449 * \brief Changes the maximum CPU utilization of a computation task.
452 * For VMs, there is a pitfall. Please see MSG_vm_set_bound().
454 void MSG_task_set_bound(msg_task_t task, double bound)
456 xbt_assert(task, "Invalid parameter");
457 xbt_assert(task->simdata, "Invalid parameter");
460 XBT_INFO("bound == 0 means no capping (i.e., unlimited).");
462 task->simdata->bound = bound;
463 if (task->simdata->compute)
464 simcall_host_execution_set_bound(task->simdata->compute,
465 task->simdata->bound);
469 /** \ingroup m_task_management
470 * \brief Changes the CPU affinity of a computation task.
472 * When pinning the given task to the first CPU core of the given host, use
473 * 0x01 for the mask value. Each bit of the mask value corresponds to each CPU
474 * core. See taskset(1) on Linux.
476 * \param task a target task
477 * \param host the host having a multi-core CPU
478 * \param mask the bit mask of a new CPU affinity setting for the task
482 * 0. Define a host with multiple cores.
483 * \<host id="PM0" power="1E8" core="2"/\>
485 * 1. Pin a given task to the first CPU core of a host.
486 * MSG_task_set_affinity(task, pm0, 0x01);
488 * 2. Pin a given task to the third CPU core of a host. Turn on the third bit of the mask.
489 * MSG_task_set_affinity(task, pm0, 0x04); // 0x04 == 100B
491 * 3. Pin a given VM to the first CPU core of a host.
492 * MSG_vm_set_affinity(vm, pm0, 0x01);
494 * See examples/msg/cloud/multicore.c for more information.
498 * 1. The current code does not allow an affinity of a task to multiple cores.
499 * The mask value 0x03 (i.e., a given task will be executed on the first core
500 * or the second core) is not allowed. The mask value 0x01 or 0x02 works. See
501 * cpu_cas01.c for details.
503 * 2. It is recommended to first compare simulation results in both the Lazy
504 * and Full calculation modes (using --cfg=cpu/optim:Full or not). Fix
505 * cpu_cas01.c if you find wrong results in the Lazy mode.
508 void MSG_task_set_affinity(msg_task_t task, msg_host_t host, unsigned long mask)
510 xbt_assert(task, "Invalid parameter");
511 xbt_assert(task->simdata, "Invalid parameter");
516 /* We need remove_ext() not throwing exception. */
517 void *ret = xbt_dict_get_or_null_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(msg_host_t));
519 xbt_dict_remove_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(host));
522 xbt_dict_set_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(host), (void *) mask, NULL);
524 /* We set affinity data of this task. If the task is being executed, we
525 * actually change the affinity setting of the task. Otherwise, this change
526 * will be applied when the task is executed. */
528 if (!task->simdata->compute) {
529 /* task is not yet executed */
530 XBT_INFO("set affinity(0x%04lx@%s) for %s (not active now)", mask, MSG_host_get_name(host), MSG_task_get_name(task));
535 smx_action_t compute = task->simdata->compute;
536 msg_host_t host_now = compute->execution.host; // simix_private.h is necessary
537 if (host_now != host) {
538 /* task is not yet executed on this host */
539 XBT_INFO("set affinity(0x%04lx@%s) for %s (not active now)", mask, MSG_host_get_name(host), MSG_task_get_name(task));
543 /* task is being executed on this host. so change the affinity now */
545 /* check it works. remove me if it works. */
546 unsigned long affinity_mask = (unsigned long) xbt_dict_get_or_null_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(msg_host_t));
547 xbt_assert(affinity_mask == mask);
550 XBT_INFO("set affinity(0x%04lx@%s) for %s", mask, MSG_host_get_name(host), MSG_task_get_name(task));
551 simcall_host_execution_set_affinity(task->simdata->compute, host, mask);