3 /* Copyright (c) 2002-2007 Arnaud Legrand. */
4 /* Copyright (c) 2007 Bruno Donassolo. */
5 /* All rights reserved. */
7 /* This program is free software; you can redistribute it and/or modify it
8 * under the terms of the license (GNU LGPL) which comes with this package. */
10 #include "msg/private.h"
11 #include "xbt/sysdep.h"
14 /** \defgroup m_task_management Managing functions of Tasks
15 * \brief This section describes the task structure of MSG
16 * (#m_task_t) and the functions for managing it.
18 /** @addtogroup m_task_management
19 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Tasks" --> \endhtmlonly
21 * Since most scheduling algorithms rely on a concept of task
22 * that can be either <em>computed</em> locally or
23 * <em>transferred</em> on another processor, it seems to be the
24 * right level of abstraction for our purposes. A <em>task</em>
25 * may then be defined by a <em>computing amount</em>, a
26 * <em>message size</em> and some <em>private data</em>.
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);
60 simdata->computation_amount = compute_duration;
61 simdata->message_size = message_size;
63 simdata->priority = 1.0;
64 simdata->refcount = 1;
65 simdata->sender = NULL;
66 simdata->receiver = NULL;
67 simdata->cond = SIMIX_cond_init();
68 simdata->mutex = SIMIX_mutex_init();
69 simdata->compute = NULL;
72 simdata->host_list = NULL;
73 simdata->comp_amount = NULL;
74 simdata->comm_amount = NULL;
79 /** prevent the task from being destroyed too quickly (but also prevent it from being sent). Mainly useful in bindings */
80 void MSG_task_ref(m_task_t t) {
81 t->simdata->refcount++;
84 /** \ingroup m_task_management
85 * \brief Return the user data of a #m_task_t.
87 * This functions checks whether \a task is a valid pointer or not and return
88 the user data associated to \a task if it is possible.
90 void *MSG_task_get_data(m_task_t task)
92 xbt_assert0((task != NULL), "Invalid parameter");
97 /** \ingroup m_task_management
98 * \brief Return the sender of a #m_task_t.
100 * This functions returns the #m_process_t which sent this task
102 m_process_t MSG_task_get_sender(m_task_t task)
104 xbt_assert0(task, "Invalid parameters");
105 return ((simdata_task_t) task->simdata)->sender;
108 /** \ingroup m_task_management
109 * \brief Return the source of a #m_task_t.
111 * This functions returns the #m_host_t from which this task was sent
113 m_host_t MSG_task_get_source(m_task_t task)
115 xbt_assert0(task, "Invalid parameters");
116 return ((simdata_task_t) task->simdata)->source;
119 /** \ingroup m_task_management
120 * \brief Return the name of a #m_task_t.
122 * This functions returns the name of a #m_task_t as specified on creation
124 const char *MSG_task_get_name(m_task_t task)
126 xbt_assert0(task, "Invalid parameters");
131 /** \ingroup m_task_management
132 * \brief Destroy a #m_task_t.
134 * Destructor for #m_task_t. Note that you should free user data, if any, \b
135 before calling this function.
137 MSG_error_t MSG_task_destroy(m_task_t task)
139 smx_action_t action = NULL;
140 xbt_assert0((task != NULL), "Invalid parameter");
142 /* why? if somebody is using, then you can't free! ok... but will return MSG_OK? when this task will be destroyed? isn't the user code wrong? */
143 task->simdata->refcount--;
144 if (task->simdata->refcount > 0)
150 SIMIX_cond_destroy(task->simdata->cond);
151 SIMIX_mutex_destroy(task->simdata->mutex);
153 action = task->simdata->compute;
155 SIMIX_action_destroy(action);
157 /* parallel tasks only */
158 if (task->simdata->host_list)
159 xbt_free(task->simdata->host_list);
161 /* free main structures */
162 xbt_free(task->simdata);
169 /** \ingroup m_task_management
170 * \brief Cancel a #m_task_t.
171 * \param task the taskt to cancel. If it was executed or transfered, it
172 stops the process that were working on it.
174 MSG_error_t MSG_task_cancel(m_task_t task)
176 xbt_assert0((task != NULL), "Invalid parameter");
178 if (task->simdata->compute) {
179 SIMIX_action_cancel(task->simdata->compute);
182 if (task->simdata->comm) {
183 SIMIX_communication_cancel(task->simdata->comm);
189 /** \ingroup m_task_management
190 * \brief Returns the computation amount needed to process a task #m_task_t.
191 * Once a task has been processed, this amount is thus set to 0...
193 double MSG_task_get_compute_duration(m_task_t task)
195 xbt_assert0((task != NULL)
196 && (task->simdata != NULL), "Invalid parameter");
198 return task->simdata->computation_amount;
201 /** \ingroup m_task_management
202 * \brief Returns the remaining computation amount of a task #m_task_t.
205 double MSG_task_get_remaining_computation(m_task_t task)
207 xbt_assert0((task != NULL)
208 && (task->simdata != NULL), "Invalid parameter");
210 if (task->simdata->compute) {
211 return SIMIX_action_get_remains(task->simdata->compute);
213 return task->simdata->computation_amount;
219 /** \ingroup m_task_management
220 * \brief Returns the total amount received by a task #m_task_t.
223 double MSG_task_get_remaining_communication(m_task_t task)
225 xbt_assert0((task != NULL)
226 && (task->simdata != NULL), "Invalid parameter");
228 return SIMIX_communication_get_remains(task->simdata->comm);
231 /** \ingroup m_task_management
232 * \brief Returns the size of the data attached to a task #m_task_t.
235 double MSG_task_get_data_size(m_task_t task)
237 xbt_assert0((task != NULL)
238 && (task->simdata != NULL), "Invalid parameter");
240 return task->simdata->message_size;
245 /** \ingroup m_task_management
246 * \brief Changes the priority of a computation task. This priority doesn't affect
247 * the transfer rate. A priority of 2 will make a task receive two times more
248 * cpu power than the other ones.
251 void MSG_task_set_priority(m_task_t task, double priority)
253 xbt_assert0((task != NULL)
254 && (task->simdata != NULL), "Invalid parameter");
256 task->simdata->priority = 1 / priority;
257 if (task->simdata->compute)
258 SIMIX_action_set_priority(task->simdata->compute,
259 task->simdata->priority);