1 /* Copyright (c) 2004-2014. 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 "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 flop_amount 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 flop_amount,
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->bytes_amount = message_size;
61 simdata->flops_amount = flop_amount;
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->flops_parallel_amount = NULL;
74 simdata->bytes_parallel_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 flops_amount an array of \p host_nb doubles.
92 * flops_amount[i] is the total number of operations that have to be performed on host_list[i].
93 * \param bytes_amount an array of \p host_nb* \p host_nb doubles.
94 * \param data a pointer to any data may want to attach to the new object.
95 * It is for user-level information and can be NULL.
96 * It can be retrieved with the function \ref MSG_task_get_data.
98 * \return The new corresponding object.
101 MSG_parallel_task_create(const char *name, int host_nb,
102 const msg_host_t * host_list,
103 double *flops_amount,
104 double *bytes_amount, void *data)
106 msg_task_t task = MSG_task_create(name, 0, 0, data);
107 simdata_task_t simdata = task->simdata;
110 /* Simulator Data specific to parallel tasks */
111 simdata->host_nb = host_nb;
112 simdata->host_list = xbt_new0(smx_host_t, host_nb);
113 simdata->flops_parallel_amount = flops_amount;
114 simdata->bytes_parallel_amount = bytes_amount;
116 for (i = 0; i < host_nb; i++)
117 simdata->host_list[i] = host_list[i];
122 /*************** Begin GPU ***************/
123 /** \ingroup m_task_management
124 * \brief Creates a new #msg_gpu_task_t.
126 * A constructor for #msg_gpu_task_t taking four arguments and returning
127 a pointer to the new created GPU task.
129 * \param name a name for the object. It is for user-level information
132 * \param flops_amount a value of the processing amount (in flop)
133 needed to process this new task. If 0, then it cannot be executed with
134 MSG_gpu_task_execute(). This value has to be >=0.
136 * \param dispatch_latency time in seconds to load this task on the GPU
138 * \param collect_latency time in seconds to transfer result from the GPU
139 back to the CPU (host) when done
141 * \see msg_gpu_task_t
142 * \return The new corresponding object.
144 msg_gpu_task_t MSG_gpu_task_create(const char *name, double flops_amount,
145 double dispatch_latency, double collect_latency)
147 msg_gpu_task_t task = xbt_new(s_msg_gpu_task_t, 1);
148 simdata_gpu_task_t simdata = xbt_new(s_simdata_gpu_task_t, 1);
149 task->simdata = simdata;
151 task->name = xbt_strdup(name);
154 simdata->flops_amount = flops_amount;
155 simdata->dispatch_latency = dispatch_latency;
156 simdata->collect_latency = collect_latency;
160 /* TRACE_msg_gpu_task_create(task); */
165 /*************** End GPU ***************/
167 /** \ingroup m_task_management
168 * \brief Return the user data of a #msg_task_t.
170 * This function checks whether \a task is a valid pointer or not and return
171 the user data associated to \a task if it is possible.
173 void *MSG_task_get_data(msg_task_t task)
175 xbt_assert((task != NULL), "Invalid parameter");
180 /** \ingroup m_task_management
181 * \brief Sets the user data of a #msg_task_t.
183 * This function allows to associate a new pointer to
184 the user data associated of \a task.
186 void MSG_task_set_data(msg_task_t task, void *data)
188 xbt_assert((task != NULL), "Invalid parameter");
193 /** \ingroup m_task_management
194 * \brief Sets a function to be called when a task has just been copied.
195 * \param callback a callback function
197 void MSG_task_set_copy_callback(void (*callback)
198 (msg_task_t task, msg_process_t sender, msg_process_t receiver)) {
200 msg_global->task_copy_callback = callback;
203 SIMIX_comm_set_copy_data_callback(MSG_comm_copy_data_from_SIMIX);
206 SIMIX_comm_set_copy_data_callback(SIMIX_comm_copy_pointer_callback);
210 /** \ingroup m_task_management
211 * \brief Return the sender of a #msg_task_t.
213 * This functions returns the #msg_process_t which sent this task
215 msg_process_t MSG_task_get_sender(msg_task_t task)
217 xbt_assert(task, "Invalid parameters");
218 return ((simdata_task_t) task->simdata)->sender;
221 /** \ingroup m_task_management
222 * \brief Return the source of a #msg_task_t.
224 * This functions returns the #msg_host_t from which this task was sent
226 msg_host_t MSG_task_get_source(msg_task_t task)
228 xbt_assert(task, "Invalid parameters");
229 return ((simdata_task_t) task->simdata)->source;
232 /** \ingroup m_task_management
233 * \brief Return the name of a #msg_task_t.
235 * This functions returns the name of a #msg_task_t as specified on creation
237 const char *MSG_task_get_name(msg_task_t task)
239 xbt_assert(task, "Invalid parameters");
243 /** \ingroup m_task_management
244 * \brief Sets the name of a #msg_task_t.
246 * This functions allows to associate a name to a task
248 void MSG_task_set_name(msg_task_t task, const char *name)
250 xbt_assert(task, "Invalid parameters");
251 task->name = xbt_strdup(name);
254 /** \ingroup m_task_management
255 * \brief Destroy a #msg_task_t.
257 * Destructor for #msg_task_t. Note that you should free user data, if any, \b
258 * before calling this function.
260 * Only the process that owns the task can destroy it.
261 * The owner changes after a successful send.
262 * If a task is successfully sent, the receiver becomes the owner and is
263 * supposed to destroy it. The sender should not use it anymore.
264 * If the task failed to be sent, the sender remains the owner of the task.
266 msg_error_t MSG_task_destroy(msg_task_t task)
268 smx_synchro_t action = NULL;
269 xbt_assert((task != NULL), "Invalid parameter");
271 if (task->simdata->isused) {
272 /* the task is being sent or executed: cancel it first */
273 MSG_task_cancel(task);
276 TRACE_msg_task_destroy(task);
279 xbt_free(task->name);
281 action = task->simdata->compute;
283 simcall_host_execution_destroy(action);
285 /* parallel tasks only */
286 xbt_free(task->simdata->host_list);
288 xbt_dict_free(&task->simdata->affinity_mask_db);
290 /* free main structures */
291 xbt_free(task->simdata);
298 /** \ingroup m_task_usage
299 * \brief Cancel a #msg_task_t.
300 * \param task the task to cancel. If it was executed or transfered, it
301 stops the process that were working on it.
303 msg_error_t MSG_task_cancel(msg_task_t task)
305 xbt_assert((task != NULL), "Cannot cancel a NULL task");
307 if (task->simdata->compute) {
308 simcall_host_execution_cancel(task->simdata->compute);
310 else if (task->simdata->comm) {
311 simdata_task_t simdata = task->simdata;
312 simcall_comm_cancel(simdata->comm);
313 if (msg_global->debug_multiple_use && simdata->isused!=0)
314 xbt_ex_free(*(xbt_ex_t*)simdata->isused);
320 /** \ingroup m_task_management
321 * \brief Returns the computation amount needed to process a task #msg_task_t.
323 * Once a task has been processed, this amount is set to 0. If you want, you
324 * can reset this value with #MSG_task_set_compute_duration before restarting the task.
326 double MSG_task_get_compute_duration(msg_task_t task)
328 xbt_assert((task != NULL)
329 && (task->simdata != NULL), "Invalid parameter");
331 return task->simdata->flops_amount;
335 /** \ingroup m_task_management
336 * \brief set the computation amount needed to process a task #msg_task_t.
338 * \warning If the computation is ongoing (already started and not finished),
339 * it is not modified by this call. Moreover, after its completion, the ongoing
340 * execution with set the flops_amount to zero, overriding any value set during
344 void MSG_task_set_flops_amount(msg_task_t task, double flops_amount)
346 task->simdata->flops_amount = flops_amount;
349 /** \ingroup m_task_management
350 * \brief set the amount data attached with a task #msg_task_t.
352 * \warning If the transfer is ongoing (already started and not finished),
353 * it is not modified by this call.
356 void MSG_task_set_bytes_amount(msg_task_t task, double data_size)
358 task->simdata->bytes_amount = data_size;
363 /** \ingroup m_task_management
364 * \brief Returns the remaining computation amount of a task #msg_task_t.
366 * If the task is ongoing, this call retrieves the remaining amount of work.
367 * If it is not ongoing, it returns the total amount of work that will be
368 * executed when the task starts.
370 double MSG_task_get_remaining_computation(msg_task_t task)
372 xbt_assert((task != NULL)
373 && (task->simdata != NULL), "Invalid parameter");
375 if (task->simdata->compute) {
376 return simcall_host_execution_get_remains(task->simdata->compute);
378 return task->simdata->flops_amount;
382 /** \ingroup m_task_management
383 * \brief Returns the total amount received by a task #msg_task_t.
384 * If the communication does not exist it will return 0.
385 * So, if the communication has FINISHED or FAILED it returns
388 double MSG_task_get_remaining_communication(msg_task_t task)
390 xbt_assert((task != NULL)
391 && (task->simdata != NULL), "Invalid parameter");
392 XBT_DEBUG("calling simcall_communication_get_remains(%p)",
393 task->simdata->comm);
394 return simcall_comm_get_remains(task->simdata->comm);
397 #ifdef HAVE_LATENCY_BOUND_TRACKING
398 /** \ingroup m_task_management
399 * \brief Return 1 if communication task is limited by latency, 0 otherwise
402 int MSG_task_is_latency_bounded(msg_task_t task)
404 xbt_assert((task != NULL)
405 && (task->simdata != NULL), "Invalid parameter");
406 XBT_DEBUG("calling simcall_communication_is_latency_bounded(%p)",
407 task->simdata->comm);
408 return simcall_comm_is_latency_bounded(task->simdata->comm);
412 /** \ingroup m_task_management
413 * \brief Returns the size of the data attached to a task #msg_task_t.
416 double MSG_task_get_bytes_amount(msg_task_t task)
418 xbt_assert((task != NULL)
419 && (task->simdata != NULL), "Invalid parameter");
421 return task->simdata->bytes_amount;
426 /** \ingroup m_task_management
427 * \brief Changes the priority of a computation task. This priority doesn't affect
428 * the transfer rate. A priority of 2 will make a task receive two times more
429 * cpu power than the other ones.
432 void MSG_task_set_priority(msg_task_t task, double priority)
434 xbt_assert((task != NULL)
435 && (task->simdata != NULL), "Invalid parameter");
437 task->simdata->priority = 1 / priority;
438 if (task->simdata->compute)
439 simcall_host_execution_set_priority(task->simdata->compute,
440 task->simdata->priority);
444 /** \ingroup m_task_management
445 * \brief Changes the maximum CPU utilization of a computation task.
448 * For VMs, there is a pitfall. Please see MSG_vm_set_bound().
450 void MSG_task_set_bound(msg_task_t task, double bound)
452 xbt_assert(task, "Invalid parameter");
453 xbt_assert(task->simdata, "Invalid parameter");
456 XBT_INFO("bound == 0 means no capping (i.e., unlimited).");
458 task->simdata->bound = bound;
459 if (task->simdata->compute)
460 simcall_host_execution_set_bound(task->simdata->compute,
461 task->simdata->bound);
465 /** \ingroup m_task_management
466 * \brief Changes the CPU affinity of a computation task.
468 * When pinning the given task to the first CPU core of the given host, use
469 * 0x01 for the mask value. Each bit of the mask value corresponds to each CPU
470 * core. See taskset(1) on Linux.
472 * \param task a target task
473 * \param host the host having a multi-core CPU
474 * \param mask the bit mask of a new CPU affinity setting for the task
478 * 0. Define a host with multiple cores.
479 * \<host id="PM0" power="1E8" core="2"/\>
481 * 1. Pin a given task to the first CPU core of a host.
482 * MSG_task_set_affinity(task, pm0, 0x01);
484 * 2. Pin a given task to the third CPU core of a host. Turn on the third bit of the mask.
485 * MSG_task_set_affinity(task, pm0, 0x04); // 0x04 == 100B
487 * 3. Pin a given VM to the first CPU core of a host.
488 * MSG_vm_set_affinity(vm, pm0, 0x01);
490 * See examples/msg/cloud/multicore.c for more information.
494 * 1. The current code does not allow an affinity of a task to multiple cores.
495 * The mask value 0x03 (i.e., a given task will be executed on the first core
496 * or the second core) is not allowed. The mask value 0x01 or 0x02 works. See
497 * cpu_cas01.c for details.
499 * 2. It is recommended to first compare simulation results in both the Lazy
500 * and Full calculation modes (using --cfg=cpu/optim:Full or not). Fix
501 * cpu_cas01.c if you find wrong results in the Lazy mode.
504 void MSG_task_set_affinity(msg_task_t task, msg_host_t host, unsigned long mask)
506 xbt_assert(task, "Invalid parameter");
507 xbt_assert(task->simdata, "Invalid parameter");
512 /* We need remove_ext() not throwing exception. */
513 void *ret = xbt_dict_get_or_null_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(msg_host_t));
515 xbt_dict_remove_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(host));
518 xbt_dict_set_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(host), (void *) mask, NULL);
520 /* We set affinity data of this task. If the task is being executed, we
521 * actually change the affinity setting of the task. Otherwise, this change
522 * will be applied when the task is executed. */
524 if (!task->simdata->compute) {
525 /* task is not yet executed */
526 XBT_INFO("set affinity(0x%04lx@%s) for %s (not active now)", mask, MSG_host_get_name(host), MSG_task_get_name(task));
531 smx_synchro_t compute = task->simdata->compute;
532 msg_host_t host_now = compute->execution.host; // simix_private.h is necessary
533 if (host_now != host) {
534 /* task is not yet executed on this host */
535 XBT_INFO("set affinity(0x%04lx@%s) for %s (not active now)", mask, MSG_host_get_name(host), MSG_task_get_name(task));
539 /* task is being executed on this host. so change the affinity now */
541 /* check it works. remove me if it works. */
542 xbt_assert((unsigned long) xbt_dict_get_or_null_ext(task->simdata->affinity_mask_db, (char *) host, sizeof(msg_host_t)) == mask);
545 XBT_INFO("set affinity(0x%04lx@%s) for %s", mask, MSG_host_get_name(host), MSG_task_get_name(task));
546 simcall_host_execution_set_affinity(task->simdata->compute, host, mask);