1 /* Copyright (c) 2006-2021. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 #ifndef SIMGRID_S4U_ACTOR_HPP
7 #define SIMGRID_S4U_ACTOR_HPP
9 #include <simgrid/forward.h>
11 #include <simgrid/chrono.hpp>
12 #include <xbt/Extendable.hpp>
13 #include <xbt/signal.hpp>
14 #include <xbt/string.hpp>
17 #include <unordered_map>
21 extern template class XBT_PUBLIC xbt::Extendable<s4u::Actor>;
25 /** An actor is an independent stream of execution in your distributed application.
28 * It is located on a (simulated) :cpp:class:`host <simgrid::s4u::Host>`, but can interact
29 * with the whole simulated platform.
31 * You can think of an actor as a process in your distributed application, or as a thread in a multithreaded program.
32 * This is the only component in SimGrid that actually does something on its own, executing its own code.
33 * A resource will not get used if you don't schedule activities on them. This is the code of Actors that create and
34 * schedule these activities. **Please refer to the** :ref:`examples <s4u_ex_actors>` **for more information.**
36 * This API is strongly inspired from the C++11 threads.
37 * The `documentation of this standard <http://en.cppreference.com/w/cpp/thread>`_
38 * may help to understand the philosophy of the SimGrid actors.
42 class XBT_PUBLIC Actor : public xbt::Extendable<Actor> {
46 friend kernel::actor::ActorImpl;
47 friend kernel::activity::MailboxImpl;
49 kernel::actor::ActorImpl* const pimpl_;
52 explicit Actor(kernel::actor::ActorImpl* pimpl) : pimpl_(pimpl) {}
56 // ***** No copy *****
57 Actor(Actor const&) = delete;
58 Actor& operator=(Actor const&) = delete;
60 // ***** Reference count *****
61 friend XBT_PUBLIC void intrusive_ptr_add_ref(const Actor* actor);
62 friend XBT_PUBLIC void intrusive_ptr_release(const Actor* actor);
64 /** Retrieve the amount of references on that object. Useful to debug the automatic refcounting */
65 int get_refcount() const;
67 // ***** Actor creation *****
68 /** Retrieve a reference to myself */
72 static xbt::signal<void(Actor&)> on_creation;
73 static xbt::signal<void(Actor const&)> on_suspend;
74 static xbt::signal<void(Actor const&)> on_resume;
75 static xbt::signal<void(Actor const&)> on_sleep;
76 static xbt::signal<void(Actor const&)> on_wake_up;
77 static xbt::signal<void(const Actor&, const Host& previous_location)> on_host_change;
78 static xbt::signal<void(Actor const&)> on_termination;
79 static xbt::signal<void(Actor const&)> on_destruction;
83 /** Add a callback fired when a new actor has been created **/
84 static void on_creation_cb(const std::function<void(Actor&)>& cb) { on_creation.connect(cb); }
85 /** Add a callback fired when an actor has been suspended**/
86 static void on_suspend_cb(const std::function<void(Actor const&)> cb) { on_suspend.connect(cb); }
87 /** Add a callback fired when an actor has been resumed **/
88 static void on_resume_cb(const std::function<void(Actor const&)>& cb) { on_resume.connect(cb); }
89 /** Add a callback fired when an actor starts sleeping **/
90 static void on_sleep_cb(const std::function<void(Actor const&)>& cb) { on_sleep.connect(cb); }
91 /** Add a callback fired when an actor wakes up from a sleep **/
92 static void on_wake_up_cb(const std::function<void(Actor const&)>& cb) { on_wake_up.connect(cb); }
93 /** Add a callback fired when an actor is has been migrated to another host **/
94 static void on_host_change_cb(const std::function<void(const Actor&, const Host& previous_location)>& cb)
96 on_host_change.connect(cb);
99 /** Add a callback fired when an actor terminates its code.
101 * The actor may continue to exist if it is still referenced in the simulation, but it's not active anymore.
102 * If you want to free extra data when the actor's destructor is called, use :cpp:var:`Actor::on_destruction`.
103 * If you want to register to the termination of a given actor, use :cpp:func:`this_actor::on_exit()` instead.
106 static void on_termination_cb(const std::function<void(Actor const&)>& cb) { on_termination.connect(cb); }
107 /** Add a callback fired when an actor is about to disappear (its destructor was called).
108 * This signal is fired for any destructed actor, which is mostly useful when designing plugins and extensions.
109 * If you want to react to the end of the actor's code, use Actor::on_termination instead.
110 * If you want to register to the termination of a given actor, use this_actor::on_exit() instead.*/
111 static void on_destruction_cb(const std::function<void(Actor const&)>& cb) { on_destruction.connect(cb); }
113 /** Create an actor from a std::function<void()>.
114 * If the actor is restarted, it gets a fresh copy of the function. */
115 static ActorPtr create(const std::string& name, s4u::Host* host, const std::function<void()>& code);
116 /** Create an actor, but don't start it yet.
118 * This is useful to set some properties or extension before actually starting it */
119 static ActorPtr init(const std::string& name, s4u::Host* host);
120 ActorPtr set_stacksize(unsigned stacksize);
121 /** Start a previously initialized actor */
122 ActorPtr start(const std::function<void()>& code);
124 template <class F> ActorPtr start(F code) { return start(std::function<void()>(std::move(code))); }
126 template <class F, class... Args,
127 // This constructor is enabled only if the call code(args...) is valid:
128 #ifndef DOXYGEN /* breathe seem to choke on function signatures in template parameter, see breathe#611 */
129 typename = typename std::result_of_t<F(Args...)>
132 ActorPtr start(F code, Args... args)
134 return start(std::bind(std::move(code), std::move(args)...));
137 ActorPtr start(const std::function<void()>& code, std::vector<std::string> args);
139 /** Create an actor from a callable thing. */
140 template <class F> static ActorPtr create(const std::string& name, s4u::Host* host, F code)
142 return create(name, host, std::function<void()>(std::move(code)));
145 /** Create an actor using a callable thing and its arguments.
147 * Note that the arguments will be copied, so move-only parameters are forbidden */
149 template <class F, class... Args,
150 // This constructor is enabled only if the call code(args...) is valid:
151 #ifndef DOXYGEN /* breathe seem to choke on function signatures in template parameter, see breathe#611 */
152 typename = typename std::result_of_t<F(Args...)>
155 static ActorPtr create(const std::string& name, s4u::Host* host, F code, Args... args)
157 return create(name, host, std::bind(std::move(code), std::move(args)...));
160 /** Create actor from function name and a vector of strings as arguments. */
161 static ActorPtr create(const std::string& name, s4u::Host* host, const std::string& function,
162 std::vector<std::string> args);
164 // ***** Methods *****
165 /** This actor will be automatically terminated when the last non-daemon actor finishes **/
168 /** Returns whether or not this actor has been daemonized or not **/
169 bool is_daemon() const;
170 static bool is_maestro();
172 /** Retrieves the name of that actor as a C++ string */
173 const simgrid::xbt::string& get_name() const;
174 /** Retrieves the name of that actor as a C string */
175 const char* get_cname() const;
176 /** Retrieves the host on which that actor is running */
177 Host* get_host() const;
178 /** Retrieves the actor ID of that actor */
179 aid_t get_pid() const;
180 /** Retrieves the actor ID of that actor's creator */
181 aid_t get_ppid() const;
183 /** Suspend an actor, that is blocked until resumeed by another actor */
186 /** Resume an actor that was previously suspended */
189 /** Returns true if the actor is suspended. */
190 bool is_suspended() const;
192 /** If set to true, the actor will automatically restart when its host reboots */
193 void set_auto_restart(bool autorestart);
195 /** Add a function to the list of "on_exit" functions for the current actor. The on_exit functions are the functions
196 * executed when your actor is killed. You should use them to free the data used by your actor.
198 * Please note that functions registered in this signal cannot do any simcall themselves. It means that they cannot
199 * send or receive messages, acquire or release mutexes, nor even modify a host property or something. Not only are
200 * blocking functions forbidden in this setting, but also modifications to the global state.
202 * The parameter of on_exit's callbacks denotes whether or not the actor's execution failed.
203 * It will be set to true if the actor was killed or failed because of an exception,
204 * while it will remain to false if the actor terminated gracefully.
206 void on_exit(const std::function<void(bool /*failed*/)>& fun) const;
208 /** Sets the time at which that actor should be killed */
209 void set_kill_time(double time);
210 /** Retrieves the time at which that actor will be killed (or -1 if not set) */
211 double get_kill_time() const;
213 /** @brief Moves the actor to another host
215 * If the actor is currently blocked on an execution activity, the activity is also
216 * migrated to the new host. If it's blocked on another kind of activity, an error is
217 * raised as the mandated code is not written yet. Please report that bug if you need it.
219 * Asynchronous activities started by the actor are not migrated automatically, so you have
220 * to take care of this yourself (only you knows which ones should be migrated).
222 void set_host(Host* new_host);
224 /** Ask the actor to die.
226 * Any blocking activity will be canceled, and it will be rescheduled to free its memory.
227 * Being killed is not something that actors can defer or avoid.
231 /** Retrieves the actor that have the given PID (or nullptr if not existing) */
232 static ActorPtr by_pid(aid_t pid);
234 /** Wait for the actor to finish.
236 * Blocks the calling actor until the joined actor is terminated. If actor alice executes bob.join(), then alice is
237 * blocked until bob terminates.
241 /** Wait for the actor to finish, or for the timeout to elapse.
243 * Blocks the calling actor until the joined actor is terminated. If actor alice executes bob.join(), then alice is
244 * blocked until bob terminates.
246 void join(double timeout) const;
247 /** Kill that actor and restart it from start. */
250 /** Kill all actors (but the issuer). Being killed is not something that actors can delay or avoid. */
251 static void kill_all();
253 /** Returns the internal implementation of this actor */
254 kernel::actor::ActorImpl* get_impl() const { return pimpl_; }
256 /** Retrieve the list of properties for that actor */
257 const std::unordered_map<std::string, std::string>*
258 get_properties() const; // FIXME: do not export the map, but only the keys or something
260 /** Retrieve the property value (or nullptr if not set) */
261 const char* get_property(const std::string& key) const;
263 /** Set a property (old values will be overwritten) */
264 void set_property(const std::string& key, const std::string& value);
268 * @brief Static methods working on the current actor (see @ref s4u::Actor) */
269 namespace this_actor {
271 XBT_PUBLIC bool is_maestro();
273 /** Block the current actor sleeping for that amount of seconds */
274 XBT_PUBLIC void sleep_for(double duration);
275 /** Block the current actor sleeping until the specified timestamp */
276 XBT_PUBLIC void sleep_until(double wakeup_time);
278 template <class Rep, class Period> inline void sleep_for(std::chrono::duration<Rep, Period> duration)
280 auto seconds = std::chrono::duration_cast<SimulationClockDuration>(duration);
281 this_actor::sleep_for(seconds.count());
284 template <class Duration> inline void sleep_until(const SimulationTimePoint<Duration>& wakeup_time)
286 auto timeout_native = std::chrono::time_point_cast<SimulationClockDuration>(wakeup_time);
287 this_actor::sleep_until(timeout_native.time_since_epoch().count());
290 /** Block the current actor, computing the given amount of flops */
291 XBT_PUBLIC void execute(double flop);
293 /** Block the current actor, computing the given amount of flops at the given priority.
294 * An execution of priority 2 computes twice as fast as an execution at priority 1. */
295 XBT_PUBLIC void execute(double flop, double priority);
298 * @example examples/cpp/exec-ptask/s4u-exec-ptask.cpp
301 /** Block the current actor until the built parallel execution terminates
304 * .. _API_s4u_parallel_execute:
306 * **Example of use:** `examples/cpp/exec-ptask/s4u-exec-ptask.cpp
307 * <https://framagit.org/simgrid/simgrid/tree/master/examples/cpp/exec-ptask/s4u-exec-ptask.cpp>`_
309 * Parallel executions convenient abstractions of parallel computational kernels that span over several machines,
310 * such as a PDGEM and the other ScaLAPACK routines. If you are interested in the effects of such parallel kernel
311 * on the platform (e.g. to schedule them wisely), there is no need to model them in all details of their internal
312 * execution and communications. It is much more convenient to model them as a single execution activity that spans
313 * over several hosts. This is exactly what s4u's Parallel Executions are.
315 * To build such an object, you need to provide a list of hosts that are involved in the parallel kernel (the
316 * actor's own host may or may not be in this list) and specify the amount of computations that should be done by
317 * each host, using a vector of flops amount. Then, you should specify the amount of data exchanged between each
318 * hosts during the parallel kernel. For that, a matrix of values is expected.
320 * It is OK to build a parallel execution without any computation and/or without any communication.
321 * Just pass an empty vector to the corresponding parameter.
323 * For example, if your list of hosts is ``[host0, host1]``, passing a vector ``[1000, 2000]`` as a `flops_amount`
324 * vector means that `host0` should compute 1000 flops while `host1` will compute 2000 flops. A matrix of
325 * communications' sizes of ``[0, 1, 2, 3]`` specifies the following data exchanges:
327 * - from host0: [ to host0: 0 bytes; to host1: 1 byte ]
329 * - from host1: [ to host0: 2 bytes; to host1: 3 bytes ]
331 * Or, in other words:
333 * - From host0 to host0: 0 bytes are exchanged
335 * - From host0 to host1: 1 byte is exchanged
337 * - From host1 to host0: 2 bytes are exchanged
339 * - From host1 to host1: 3 bytes are exchanged
341 * In a parallel execution, all parts (all executions on each hosts, all communications) progress exactly at the
342 * same pace, so they all terminate at the exact same pace. If one part is slow because of a slow resource or
343 * because of contention, this slows down the parallel execution as a whole.
345 * These objects are somewhat surprising from a modeling point of view. For example, the unit of their speed is
346 * somewhere between flop/sec and byte/sec. Arbitrary parallel executions will simply not work with the usual platform
347 * models, and you must :ref:`use the ptask_L07 host model <options_model_select>` for that. Note that you can mix
348 * regular executions and communications with parallel executions, provided that the host model is ptask_L07.
352 /** Block the current actor until the built parallel execution completes */
353 XBT_PUBLIC void parallel_execute(const std::vector<s4u::Host*>& hosts, const std::vector<double>& flops_amounts,
354 const std::vector<double>& bytes_amounts);
356 /** Initialize a sequential execution that must then be started manually */
357 XBT_PUBLIC ExecPtr exec_init(double flops_amounts);
358 /** Initialize a parallel execution that must then be started manually */
359 XBT_PUBLIC ExecPtr exec_init(const std::vector<s4u::Host*>& hosts, const std::vector<double>& flops_amounts,
360 const std::vector<double>& bytes_amounts);
362 XBT_PUBLIC ExecPtr exec_async(double flops_amounts);
364 /** @brief Returns the actor ID of the current actor. */
365 XBT_PUBLIC aid_t get_pid();
367 /** @brief Returns the ancestor's actor ID of the current actor. */
368 XBT_PUBLIC aid_t get_ppid();
370 /** @brief Returns the name of the current actor. */
371 XBT_PUBLIC std::string get_name();
372 /** @brief Returns the name of the current actor as a C string. */
373 XBT_PUBLIC const char* get_cname();
375 /** @brief Returns the name of the host on which the current actor is running. */
376 XBT_PUBLIC Host* get_host();
378 /** @brief Suspend the current actor, that is blocked until resume()ed by another actor. */
379 XBT_PUBLIC void suspend();
381 /** @brief Yield the current actor. */
382 XBT_PUBLIC void yield();
384 /** @brief kill the current actor. */
385 XBT_ATTRIB_NORETURN XBT_PUBLIC void exit();
387 /** @brief Add a function to the list of "on_exit" functions of the current actor.
389 * The on_exit functions are the functions executed when your actor is killed. You should use them to free the data used
392 * Please note that functions registered in this signal cannot do any simcall themselves. It means that they cannot
393 * send or receive messages, acquire or release mutexes, nor even modify a host property or something. Not only are
394 * blocking functions forbidden in this setting, but also modifications to the global state.
396 * The parameter of on_exit's callbacks denotes whether or not the actor's execution failed.
397 * It will be set to true if the actor was killed or failed because of an exception or if the simulation deadlocked,
398 * while it will remain to false if the actor terminated gracefully.
401 XBT_PUBLIC void on_exit(const std::function<void(bool)>& fun);
403 /** @brief Migrate the current actor to a new host. */
404 XBT_PUBLIC void set_host(Host* new_host);
408 }} // namespace simgrid::s4u
411 #endif /* SIMGRID_S4U_ACTOR_HPP */