1 /* Copyright (c) 2004, 2005, 2006, 2007, 2008, 2009, 2010. 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 "xbt/sysdep.h"
11 /** \defgroup m_task_management Managing functions of Tasks
12 * \brief This section describes the task structure of MSG
13 * (#m_task_t) and the functions for managing it.
15 /** @addtogroup m_task_management
16 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Tasks" --> \endhtmlonly
18 * Since most scheduling algorithms rely on a concept of task
19 * that can be either <em>computed</em> locally or
20 * <em>transferred</em> on another processor, it seems to be the
21 * right level of abstraction for our purposes. A <em>task</em>
22 * may then be defined by a <em>computing amount</em>, a
23 * <em>message size</em> and some <em>private data</em>.
26 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(msg_task, msg,
27 "Logging specific to MSG (task)");
29 /********************************* Task **************************************/
30 /** \ingroup m_task_management
31 * \brief Creates a new #m_task_t.
33 * A constructor for #m_task_t taking four arguments and returning the
35 * \param name a name for the object. It is for user-level information
37 * \param compute_duration a value of the processing amount (in flop)
38 needed to process this new task. If 0, then it cannot be executed with
39 MSG_task_execute(). This value has to be >=0.
40 * \param message_size a value of the amount of data (in bytes) needed to
41 transfer this new task. If 0, then it cannot be transfered with
42 MSG_task_get() and MSG_task_put(). This value has to be >=0.
43 * \param data a pointer to any data may want to attach to the new
44 object. It is for user-level information and can be NULL. It can
45 be retrieved with the function \ref MSG_task_get_data.
47 * \return The new corresponding object.
49 m_task_t MSG_task_create(const char *name, double compute_duration,
50 double message_size, void *data)
52 m_task_t task = xbt_new(s_m_task_t, 1);
53 simdata_task_t simdata = xbt_new(s_simdata_task_t, 1);
54 task->simdata = simdata;
56 task->name = xbt_strdup(name);
61 simdata->computation_amount = compute_duration;
62 simdata->message_size = message_size;
64 simdata->priority = 1.0;
66 simdata->sender = NULL;
67 simdata->receiver = NULL;
68 simdata->compute = NULL;
71 simdata->host_list = NULL;
72 simdata->comp_amount = NULL;
73 simdata->comm_amount = NULL;
75 TRACE_msg_task_create(task);
81 /** \ingroup m_task_management
82 * \brief Return the user data of a #m_task_t.
84 * This function checks whether \a task is a valid pointer or not and return
85 the user data associated to \a task if it is possible.
87 void *MSG_task_get_data(m_task_t task)
89 xbt_assert((task != NULL), "Invalid parameter");
94 /** \ingroup m_task_management
95 * \brief Sets the user data of a #m_task_t.
97 * This function allows to associate a new pointer to
98 the user data associated of \a task.
100 void MSG_task_set_data(m_task_t task, void *data)
102 xbt_assert((task != NULL), "Invalid parameter");
107 /** \ingroup m_task_management
108 * \brief Sets a function to be called when a task has just been copied.
109 * \param callback a callback function
111 void MSG_task_set_copy_callback(void (*callback)
112 (m_task_t task, m_process_t sender, m_process_t receiver)) {
113 msg_global->task_copy_callback = callback;
116 /** \ingroup m_task_management
117 * \brief Return the sender of a #m_task_t.
119 * This functions returns the #m_process_t which sent this task
121 m_process_t MSG_task_get_sender(m_task_t task)
123 xbt_assert(task, "Invalid parameters");
124 return ((simdata_task_t) task->simdata)->sender;
127 /** \ingroup m_task_management
128 * \brief Return the source of a #m_task_t.
130 * This functions returns the #m_host_t from which this task was sent
132 m_host_t MSG_task_get_source(m_task_t task)
134 xbt_assert(task, "Invalid parameters");
135 return ((simdata_task_t) task->simdata)->source;
138 /** \ingroup m_task_management
139 * \brief Return the name of a #m_task_t.
141 * This functions returns the name of a #m_task_t as specified on creation
143 const char *MSG_task_get_name(m_task_t task)
145 xbt_assert(task, "Invalid parameters");
149 /** \ingroup m_task_management
150 * \brief Return the name of a #m_task_t.
152 * This functions allows to associate a name to a task
154 void MSG_task_set_name(m_task_t task, const char *name)
156 xbt_assert(task, "Invalid parameters");
157 task->name = xbt_strdup(name);
160 /** \ingroup m_task_management
161 * \brief Destroy a #m_task_t.
163 * Destructor for #m_task_t. Note that you should free user data, if any, \b
164 * before calling this function.
166 * Only the process that owns the task can destroy it.
167 * The owner changes after a successful send.
168 * If a task is successfully sent, the receiver becomes the owner and is
169 * supposed to destroy it. The sender should not use it anymore.
170 * If the task failed to be sent, the sender remains the owner of the task.
172 MSG_error_t MSG_task_destroy(m_task_t task)
174 smx_action_t action = NULL;
175 xbt_assert((task != NULL), "Invalid parameter");
177 if (task->simdata->isused) {
178 /* the task is being sent or executed: cancel it first */
179 MSG_task_cancel(task);
182 TRACE_msg_task_destroy(task);
185 xbt_free(task->name);
187 action = task->simdata->compute;
189 SIMIX_req_host_execution_destroy(action);
191 /* parallel tasks only */
192 xbt_free(task->simdata->host_list);
194 /* free main structures */
195 xbt_free(task->simdata);
202 /** \ingroup m_task_management
203 * \brief Cancel a #m_task_t.
204 * \param task the task to cancel. If it was executed or transfered, it
205 stops the process that were working on it.
207 MSG_error_t MSG_task_cancel(m_task_t task)
209 xbt_assert((task != NULL), "Invalid parameter");
211 if (task->simdata->compute) {
212 SIMIX_req_host_execution_cancel(task->simdata->compute);
214 else if (task->simdata->comm) {
215 SIMIX_req_comm_cancel(task->simdata->comm);
216 task->simdata->isused = 0;
221 /** \ingroup m_task_management
222 * \brief Returns the computation amount needed to process a task #m_task_t.
223 * Once a task has been processed, this amount is thus set to 0...
225 double MSG_task_get_compute_duration(m_task_t task)
227 xbt_assert((task != NULL)
228 && (task->simdata != NULL), "Invalid parameter");
230 return task->simdata->computation_amount;
234 /** \ingroup m_task_management
235 * \brief set the computation amount needed to process a task #m_task_t.
238 void MSG_task_set_compute_duration(m_task_t task,
239 double computation_amount)
241 xbt_assert(task, "Invalid parameter");
242 task->simdata->computation_amount = computation_amount;
246 /** \ingroup m_task_management
247 * \brief Returns the remaining computation amount of a task #m_task_t.
250 double MSG_task_get_remaining_computation(m_task_t task)
252 xbt_assert((task != NULL)
253 && (task->simdata != NULL), "Invalid parameter");
255 if (task->simdata->compute) {
256 return SIMIX_req_host_execution_get_remains(task->simdata->compute);
258 return task->simdata->computation_amount;
262 /** \ingroup m_task_management
263 * \brief Returns the total amount received by a task #m_task_t.
264 * If the communication does not exist it will return 0.
265 * So, if the communication has FINISHED or FAILED it returns
268 double MSG_task_get_remaining_communication(m_task_t task)
270 xbt_assert((task != NULL)
271 && (task->simdata != NULL), "Invalid parameter");
272 XBT_DEBUG("calling SIMIX_req_communication_get_remains(%p)",
273 task->simdata->comm);
274 return SIMIX_req_comm_get_remains(task->simdata->comm);
277 #ifdef HAVE_LATENCY_BOUND_TRACKING
278 /** \ingroup m_task_management
279 * \brief Return 1 if communication task is limited by latency, 0 otherwise
282 int MSG_task_is_latency_bounded(m_task_t task)
284 xbt_assert((task != NULL)
285 && (task->simdata != NULL), "Invalid parameter");
286 XBT_DEBUG("calling SIMIX_req_communication_is_latency_bounded(%p)",
287 task->simdata->comm);
288 return SIMIX_req_comm_is_latency_bounded(task->simdata->comm);
292 /** \ingroup m_task_management
293 * \brief Returns the size of the data attached to a task #m_task_t.
296 double MSG_task_get_data_size(m_task_t task)
298 xbt_assert((task != NULL)
299 && (task->simdata != NULL), "Invalid parameter");
301 return task->simdata->message_size;
306 /** \ingroup m_task_management
307 * \brief Changes the priority of a computation task. This priority doesn't affect
308 * the transfer rate. A priority of 2 will make a task receive two times more
309 * cpu power than the other ones.
312 void MSG_task_set_priority(m_task_t task, double priority)
314 xbt_assert((task != NULL)
315 && (task->simdata != NULL), "Invalid parameter");
317 task->simdata->priority = 1 / priority;
318 if (task->simdata->compute)
319 SIMIX_req_host_execution_set_priority(task->simdata->compute,
320 task->simdata->priority);