#ifndef SIMGRID_S4U_ACTOR_HPP
#define SIMGRID_S4U_ACTOR_HPP
+#include <atomic>
+#include <functional>
+#include <future>
+#include <memory>
#include <stdexcept>
+#include <type_traits>
+
#include <xbt/base.h>
+#include <xbt/functional.hpp>
+
#include <simgrid/simix.h>
#include <simgrid/s4u/forward.hpp>
namespace simgrid {
namespace s4u {
-/** @defgroup s4u_actor Actors: simulation agents
- * @addtogroup S4U_API
- */
-
-/** @addtogroup s4u_actor
- *
- * @tableofcontents
+/** @ingroup s4u_api
*
* An actor is an independent stream of execution in your distributed application.
*
* An actor is located on a (simulated) host, but it can interact
* with the whole simulated platform.
*
- * (back to the @ref s4u_api "S4U documentation")
+ * The s4u::Actor API is strongly inspired from the C++11 threads.
+ * The <a href="http://en.cppreference.com/w/cpp/thread">documentation
+ * of this standard</a> may help to understand the philosophy of the S4U
+ * Actors.
*
- * @section s4u_actor_def Defining an Actor
+ * @section s4u_actor_def Defining the skeleton of an Actor
*
- * The code of an actor (ie, the code that this actor will run when starting) the () operator.
- * In this code, your actor can use the functions of the simgrid::s4u::this_actor namespace to interact with the world.
+ * %As in the <a href="http://en.cppreference.com/w/cpp/thread">C++11
+ * standard</a>, you can declare the code of your actor either as a
+ * pure function or as an object. It is very simple with functions:
*
- * For example, a Worker actor should be declared as follows:
- *
- * \code{.cpp}
+ * @code{.cpp}
+ * #include "s4u/actor.hpp"
+ *
+ * // Declare the code of your worker
+ * void worker() {
+ * printf("Hello s4u");
+ * simgrid::s4u::this_actor::execute(5*1024*1024); // Get the worker executing a task of 5 MFlops
+ * };
+ *
+ * // From your main or from another actor, create your actor on the host Jupiter
+ * // The following line actually creates a new actor, even if there is no "new".
+ * Actor("Alice", simgrid::s4u::Host::by_name("Jupiter"), worker);
+ * @endcode
+ *
+ * But some people prefer to encapsulate their actors in classes and
+ * objects to save the actor state in a cleanly dedicated location.
+ * The syntax is slightly more complicated, but not much.
+ *
+ * @code{.cpp}
* #include "s4u/actor.hpp"
*
+ * // Declare the class representing your actors
* class Worker {
+ * public:
* void operator()() { // Two pairs of () because this defines the method called ()
* printf("Hello s4u");
* simgrid::s4u::this_actor::execute(5*1024*1024); // Get the worker executing a task of 5 MFlops
* }
* };
- * \endcode
*
- * @section s4u_actor_new Creating a new instance of your Actor
+ * // From your main or from another actor, create your actor. Note the () after Worker
+ * Actor("Bob", simgrid::s4u::Host::by_name("Jupiter"), Worker());
+ * @endcode
*
- * // Then later in your main() function or so:
- * ...
- * new Actor("worker", host, Worker());
- * ...
+ * @section s4u_actor_flesh Fleshing your actor
+ *
+ * The body of your actor can use the functions of the
+ * simgrid::s4u::this_actor namespace to interact with the world.
+ * This namespace contains the methods to start new activities
+ * (executions, communications, etc), and to get informations about
+ * the currently running thread (its location, etc).
+ *
+ * Please refer to the @link simgrid::s4u::this_actor full API @endlink.
*
- * You can start your actors with simple @c new, for example from the @c main function,
- * but this is usually considered as a bad habit as it makes it harder to test your application
- * in differing settings. Instead, you are advised to use an XML deployment file using
- * s4u::Engine::loadDeployment() to start your actors.
+ *
+ * @section s4u_actor_deploy Using a deployment file
+ *
+ * @warning This is currently not working with S4U. Sorry about that.
+ *
+ * The best practice is to use an external deployment file as
+ * follows, because it makes it easier to test your application in
+ * differing settings. Load this file with
+ * s4u::Engine::loadDeployment() before the simulation starts.
+ * Refer to the @ref deployment section for more information.
+ *
+ * @code{.xml}
+ * <?xml version='1.0'?>
+ * <!DOCTYPE platform SYSTEM "http://simgrid.gforge.inria.fr/simgrid/simgrid.dtd">
+ * <platform version="4">
+ *
+ * <!-- Start a process called 'master' on the host called 'Tremblay' -->
+ * <process host="Tremblay" function="master">
+ * <!-- Here come the parameter that you want to feed to this instance of master -->
+ * <argument value="20"/> <!-- argv[1] -->
+ * <argument value="50000000"/> <!-- argv[2] -->
+ * <argument value="1000000"/> <!-- argv[3] -->
+ * <argument value="5"/> <!-- argv[4] -->
+ * </process>
+ *
+ * <!-- Start a process called 'worker' on the host called 'Jupiter' -->
+ * <process host="Jupiter" function="worker"/> <!-- Don't provide any parameter ->>
+ *
+ * </platform>
+ * @endcode
*
* @{
*/
-
+
/** @brief Simulation Agent (see \ref s4u_actor)*/
XBT_PUBLIC_CLASS Actor {
- explicit Actor(smx_process_t smx_proc);
+private:
+ /** Wrap a (possibly non-copyable) single-use task into a `std::function` */
+ template<class F, class... Args>
+ class Task {
+ public:
+ Task(F&& code, Args&&... args) :
+ code_(std::forward<F>(code)),
+ args_(std::forward<Args>(args)...)
+ {
+ done_.clear();
+ }
+ void operator()()
+ {
+ if (done_.test_and_set())
+ throw std::logic_error("Actor task already executed");
+ simgrid::xbt::apply(std::move(code_), std::move(args_));
+ }
+ private:
+ std::atomic_flag done_;
+ F code_;
+ std::tuple<Args...> args_;
+ };
+ /** Wrap a (possibly non-copyable) single-use task into a `std::function` */
+ template<class F, class... Args>
+ static std::function<void()> wrap_task(F f, Args... args)
+ {
+ std::shared_ptr<Task<F, Args...>> task(
+ new Task<F, Args...>(std::move(f), std::move(args)...));
+ return [=] {
+ (*task)();
+ };
+ }
public:
+ Actor() : pimpl_(nullptr) {}
+ Actor(smx_process_t smx_proc) :
+ pimpl_(SIMIX_process_ref(smx_proc)) {}
+ ~Actor()
+ {
+ SIMIX_process_unref(pimpl_);
+ }
+
+ // Copy+move (with the copy-and-swap idiom):
+ Actor(Actor const& actor) : pimpl_(SIMIX_process_ref(actor.pimpl_)) {}
+ friend void swap(Actor& first, Actor& second)
+ {
+ using std::swap;
+ swap(first.pimpl_, second.pimpl_);
+ }
+ Actor& operator=(Actor actor)
+ {
+ swap(*this, actor);
+ return *this;
+ }
+ Actor(Actor&& actor) : pimpl_(nullptr)
+ {
+ swap(*this, actor);
+ }
+
+ /** Create an actor using a function
+ *
+ * If the actor is restarted, the actor has a fresh copy of the function.
+ */
Actor(const char* name, s4u::Host *host, double killTime, std::function<void()> code);
+
Actor(const char* name, s4u::Host *host, std::function<void()> code)
- : Actor(name, host, -1, std::move(code)) {};
- template<class C>
- Actor(const char* name, s4u::Host *host, C code)
- : Actor(name, host, -1, std::function<void()>(std::move(code))) {}
- ~Actor();
+ : Actor(name, host, -1.0d, std::move(code)) {};
+
+ /** Create an actor using code
+ *
+ * Using this constructor, move-only type can be used. The consequence is
+ * that we cannot copy the value and restart the process in its initial
+ * state. In order to use auto-restart, an explicit `function` must be passed
+ * instead.
+ */
+ template<class F, class... Args,
+ // This constructor is enabled only if the call code(args...) is valid:
+ typename = typename std::result_of<F(Args...)>::type
+ >
+ Actor(const char* name, s4u::Host *host, F code, Args... args) :
+ Actor(name, host, wrap_task(std::move(code), std::move(args)...))
+ {}
/** Retrieves the actor that have the given PID (or NULL if not existing) */
//static Actor *byPid(int pid); not implemented
/** Ask kindly to all actors to die. Only the issuer will survive. */
static void killAll();
-protected:
- smx_process_t getInferior() {return pimpl_;}
private:
smx_process_t pimpl_ = nullptr;
};
-/** @brief Static methods working on the current actor (see @ref s4u_actor) */
+/** @ingroup s4u_api
+ * @brief Static methods working on the current actor (see @ref s4u::Actor) */
namespace this_actor {
/** Block the actor sleeping for that amount of seconds (may throws hostFailure) */
