src/bindings/python/simgrid_python.cpp

   1 /* Copyright (c) 2018-2020. The SimGrid Team. All rights reserved.          */
   2
   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. */
   5
   6 #ifdef _WIN32
   7 #warning Try to work around https://bugs.python.org/issue11566
   8 #define _hypot hypot
   9 #endif
  10
  11 #if defined(__GNUG__)
  12 #pragma GCC diagnostic push
  13 #pragma GCC diagnostic ignored "-Wunused-value"
  14 #endif
  15
  16 #include <pybind11/functional.h>
  17 #include <pybind11/pybind11.h> // Must come before our own stuff
  18 #include <pybind11/stl.h>
  19
  20 #if defined(__GNUG__)
  21 #pragma GCC diagnostic pop
  22 #endif
  23
  24 #include "src/kernel/context/Context.hpp"
  25 #include <simgrid/Exception.hpp>
  26 #include <simgrid/s4u/Actor.hpp>
  27 #include <simgrid/s4u/Comm.hpp>
  28 #include <simgrid/s4u/Engine.hpp>
  29 #include <simgrid/s4u/Exec.hpp>
  30 #include <simgrid/s4u/Host.hpp>
  31 #include <simgrid/s4u/Mailbox.hpp>
  32 #include <simgrid/version.h>
  33
  34 #include <memory>
  35 #include <string>
  36 #include <vector>
  37
  38 namespace py = pybind11;
  39 using simgrid::s4u::Actor;
  40 using simgrid::s4u::ActorPtr;
  41 using simgrid::s4u::Engine;
  42 using simgrid::s4u::Host;
  43 using simgrid::s4u::Mailbox;
  44
  45 XBT_LOG_NEW_DEFAULT_CATEGORY(python, "python");
  46
  47 namespace {
  48
  49 static std::string get_simgrid_version()
  50 {
  51   int major;
  52   int minor;
  53   int patch;
  54   sg_version_get(&major, &minor, &patch);
  55   return simgrid::xbt::string_printf("%i.%i.%i", major, minor, patch);
  56 }
  57
  58 /* Classes GilScopedAcquire and GilScopedRelease have the same purpose as pybind11::gil_scoped_acquire and
  59  * pybind11::gil_scoped_release.  Refer to the manual of pybind11 for details:
  60  * https://pybind11.readthedocs.io/en/stable/advanced/misc.html#global-interpreter-lock-gil
  61  *
  62  * The pybind11 versions are however too sophisticated (using TLS for example) and don't work well with all kinds of
  63  * contexts.
  64  * See also https://github.com/pybind/pybind11/issues/1276, which may be related.
  65  *
  66  * Briefly, GilScopedAcquire can be used on actor creation to acquire a new PyThreadState.  The PyThreadState has to be
  67  * released for context switches (i.e. before simcalls). That's the purpose of GilScopedRelease.
  68  *
  69  * Like their pybind11 counterparts, both classes use a RAII pattern.
  70  */
  71 class XBT_PRIVATE GilScopedAcquire {
  72   static PyThreadState* acquire()
  73   {
  74     PyThreadState* state = PyThreadState_New(PyInterpreterState_Head());
  75     PyEval_AcquireThread(state);
  76     return state;
  77   }
  78   static void release(PyThreadState* state)
  79   {
  80     PyEval_ReleaseThread(state);
  81     PyThreadState_Clear(state);
  82     PyThreadState_Delete(state);
  83   }
  84
  85   std::unique_ptr<PyThreadState, decltype(&release)> thread_state{acquire(), &release};
  86
  87 public:
  88   void reset() { thread_state.reset(); }
  89 };
  90
  91 class XBT_PRIVATE GilScopedRelease {
  92   std::unique_ptr<PyThreadState, decltype(&PyEval_RestoreThread)> thread_state{PyEval_SaveThread(),
  93                                                                                &PyEval_RestoreThread};
  94 };
  95
  96 } // namespace
  97
  98 PYBIND11_DECLARE_HOLDER_TYPE(T, boost::intrusive_ptr<T>)
  99
 100 PYBIND11_MODULE(simgrid, m)
 101 {
 102   m.doc() = "SimGrid userspace API";
 103
 104   m.attr("simgrid_version") = get_simgrid_version();
 105
 106   // Internal exception used to kill actors and sweep the RAII chimney (free objects living on the stack)
 107   static py::object pyForcefulKillEx(py::register_exception<simgrid::ForcefulKillException>(m, "ActorKilled"));
 108
 109   /* this_actor namespace */
 110   m.def_submodule("this_actor", "Bindings of the s4u::this_actor namespace.")
 111       .def("info", [](const char* s) { XBT_INFO("%s", s); }, "Display a logging message of 'info' priority.")
 112       .def("error", [](const char* s) { XBT_ERROR("%s", s); }, "Display a logging message of 'error' priority.")
 113       .def("execute", py::overload_cast<double, double>(&simgrid::s4u::this_actor::execute),
 114            py::call_guard<GilScopedRelease>(),
 115            "Block the current actor, computing the given amount of flops at the given priority, "
 116            "see :cpp:func:`void simgrid::s4u::this_actor::execute(double, double)`",
 117            py::arg("flops"), py::arg("priority") = 1)
 118       .def("exec_init", py::overload_cast<double>(&simgrid::s4u::this_actor::exec_init),
 119            py::call_guard<GilScopedRelease>())
 120       .def("get_host", &simgrid::s4u::this_actor::get_host, "Retrieves host on which the current actor is located")
 121       .def("set_host", &simgrid::s4u::this_actor::set_host, py::call_guard<GilScopedRelease>(),
 122            "Moves the current actor to another host, see :cpp:func:`void simgrid::s4u::this_actor::set_host()`",
 123            py::arg("dest"))
 124       .def("sleep_for", static_cast<void (*)(double)>(&simgrid::s4u::this_actor::sleep_for),
 125            py::call_guard<GilScopedRelease>(), "Block the actor sleeping for that amount of seconds, "
 126                                                "see :cpp:func:`void simgrid::s4u::this_actor::sleep_for`",
 127            py::arg("duration"))
 128       .def("sleep_until", static_cast<void (*)(double)>(&simgrid::s4u::this_actor::sleep_until),
 129            py::call_guard<GilScopedRelease>(), "Block the actor sleeping until the specified timestamp, "
 130                                                "see :cpp:func:`void simgrid::s4u::this_actor::sleep_until`",
 131            py::arg("duration"))
 132       .def("suspend", &simgrid::s4u::this_actor::suspend, py::call_guard<GilScopedRelease>(),
 133            "Suspend the current actor, that is blocked until resume()ed by another actor. "
 134            "see :cpp:func:`void simgrid::s4u::this_actor::suspend`")
 135       .def("yield_", &simgrid::s4u::this_actor::yield, py::call_guard<GilScopedRelease>(),
 136            "Yield the actor, see :cpp:func:`void simgrid::s4u::this_actor::yield()`")
 137       .def("exit", &simgrid::s4u::this_actor::exit, py::call_guard<GilScopedRelease>(), "kill the current actor")
 138       .def("on_exit",
 139            [](py::object fun) {
 140              simgrid::s4u::this_actor::on_exit([fun](bool /*failed*/) {
 141                GilScopedAcquire py_context; // need a new context for callback
 142                try {
 143                  fun();
 144                } catch (const py::error_already_set& e) {
 145                  std::string what = e.what();
 146                  py_context.reset();
 147                  xbt_die("Error while executing the on_exit lambda: %s", what.c_str());
 148                }
 149              });
 150            },
 151            py::call_guard<GilScopedRelease>(), "");
 152
 153   /* Class Engine */
 154   py::class_<Engine>(m, "Engine", "Simulation Engine, see :ref:`class s4u::Engine <API_s4u_Engine>`")
 155       .def(py::init([](std::vector<std::string> args) {
 156         static char noarg[] = {'\0'};
 157         int argc            = args.size();
 158         std::unique_ptr<char* []> argv(new char*[argc + 1]);
 159         for (int i = 0; i != argc; ++i)
 160           argv[i] = args[i].empty() ? noarg : &args[i].front();
 161         argv[argc] = nullptr;
 162         // Currently this can be dangling, we should wrap this somehow.
 163         return new simgrid::s4u::Engine(&argc, argv.get());
 164       }))
 165       .def_static("get_clock", &Engine::get_clock,
 166                   "The simulation time, ie the amount of simulated seconds since the simulation start.")
 167       .def("get_all_hosts", &Engine::get_all_hosts, "Returns the list of all hosts found in the platform")
 168       .def("load_platform", &Engine::load_platform,
 169            "Load a platform file describing the environment, see :cpp:func:`simgrid::s4u::Engine::load_platform()`")
 170       .def("load_deployment", &Engine::load_deployment,
 171            "Load a deployment file and launch the actors that it contains, see "
 172            ":cpp:func:`simgrid::s4u::Engine::load_deployment()`")
 173       .def("run", &Engine::run, py::call_guard<GilScopedRelease>(), "Run the simulation")
 174       .def("register_actor",
 175            [](Engine* e, const std::string& name, py::object fun_or_class) {
 176              e->register_actor(name, [fun_or_class](std::vector<std::string> args) {
 177                GilScopedAcquire py_context;
 178                try {
 179                  /* Convert the std::vector into a py::tuple */
 180                  py::tuple params(args.size() - 1);
 181                  for (size_t i = 1; i < args.size(); i++)
 182                    params[i - 1] = py::cast(args[i]);
 183
 184                  py::object res = fun_or_class(*params);
 185
 186                  /* If I was passed a class, I just built an instance, so I need to call it now */
 187                  if (py::isinstance<py::function>(res))
 188                    res();
 189                } catch (const py::error_already_set& ex) {
 190                  bool ffk = ex.matches(pyForcefulKillEx);
 191                  py_context.reset();
 192                  if (ffk) {
 193                    XBT_VERB("Actor killed");
 194                    /* Forward that ForcefulKill exception */
 195                    simgrid::ForcefulKillException::do_throw();
 196                  }
 197                  throw;
 198                }
 199              });
 200            },
 201            "Registers the main function of an actor, see :cpp:func:`simgrid::s4u::Engine::register_actor()`");
 202
 203   /* Class Host */
 204   py::class_<simgrid::s4u::Host, std::unique_ptr<Host, py::nodelete>>(
 205       m, "Host", "Simulation Engine, see :ref:`class s4u::Host <API_s4u_Host>`")
 206       .def("by_name", &Host::by_name, "Retrieves a host from its name, or die")
 207       .def("get_pstate_count", &Host::get_pstate_count,
 208            "Retrieve the cound of defined pstate levels, see :cpp:func:`simgrid::s4u::Host::get_pstate_count`")
 209       .def("get_pstate_speed", &Host::get_pstate_speed,
 210            "Retrieve the maximal speed at the given pstate, see :cpp:func:`simgrid::s4u::Host::get_pstate_speed`")
 211       .def_property("pstate", &Host::get_pstate,
 212                     [](Host* h, int i) {
 213                       GilScopedRelease gil_guard;
 214                       h->set_pstate(i);
 215                     },
 216                     "The current pstate")
 217       .def("current", &Host::current, py::call_guard<GilScopedRelease>(),
 218            "Retrieves the host on which the running actor is located, see :cpp:func:`simgrid::s4u::Host::current()`")
 219       .def_property_readonly("name",
 220                              [](const Host* self) {
 221                                return std::string(self->get_name().c_str()); // Convert from xbt::string because of MC
 222                              },
 223                              "The name of this host")
 224       .def_property_readonly(
 225           "load", &Host::get_load,
 226           "Returns the current computation load (in flops per second). This is the currently achieved speed. "
 227           "See :cpp:func:`simgrid::s4u::Host::get_load()`")
 228       .def_property_readonly(
 229           "speed", &Host::get_speed,
 230           "The peak computing speed in flops/s at the current pstate, taking the external load into account. "
 231           "This is the max potential speed. See :cpp:func:`simgrid::s4u::Host::get_speed()`");
 232
 233   /* Class Mailbox */
 234   py::class_<simgrid::s4u::Mailbox, std::unique_ptr<Mailbox, py::nodelete>>(
 235       m, "Mailbox", "Mailbox, see :ref:`class s4u::Mailbox <API_s4u_Mailbox>`")
 236       .def("__str__", [](const Mailbox* self) { return std::string("Mailbox(") + self->get_cname() + ")"; },
 237            "Textual representation of the Mailbox`")
 238       .def("by_name", &Mailbox::by_name, py::call_guard<GilScopedRelease>(),
 239            "Retrieve a Mailbox from its name, see :cpp:func:`simgrid::s4u::Mailbox::by_name()`")
 240       .def_property_readonly("name",
 241                              [](const Mailbox* self) {
 242                                return std::string(self->get_name().c_str()); // Convert from xbt::string because of MC
 243                              },
 244                              "The name of that mailbox, see :cpp:func:`simgrid::s4u::Mailbox::get_name()`")
 245       .def("put",
 246            [](Mailbox* self, py::object data, int size) {
 247              data.inc_ref();
 248              self->put(data.ptr(), size);
 249            },
 250            py::call_guard<GilScopedRelease>(),
 251            "Blocking data transmission, see :cpp:func:`void simgrid::s4u::Mailbox::put(void*, uint64_t)`")
 252       .def("put_async",
 253            [](Mailbox* self, py::object data, int size) {
 254              data.inc_ref();
 255              return self->put_async(data.ptr(), size);
 256            },
 257            py::call_guard<GilScopedRelease>(),
 258            "Non-blocking data transmission, see :cpp:func:`void simgrid::s4u::Mailbox::put_async(void*, uint64_t)`")
 259       .def("get",
 260            [](Mailbox* self) {
 261              py::object data = pybind11::reinterpret_steal<py::object>(static_cast<PyObject*>(self->get()));
 262              // data.dec_ref(); // FIXME: why does it break python-actor-create?
 263              return data;
 264            },
 265            py::call_guard<GilScopedRelease>(),
 266            "Blocking data reception, see :cpp:func:`void* simgrid::s4u::Mailbox::get()`");
 267
 268   /* Class Comm */
 269   py::class_<simgrid::s4u::Comm, simgrid::s4u::CommPtr>(m, "Comm",
 270                                                         "Communication, see :ref:`class s4u::Comm <API_s4u_Comm>`")
 271       .def("test", &simgrid::s4u::Comm::test, py::call_guard<GilScopedRelease>(),
 272            "Test whether the communication is terminated, see :cpp:func:`simgrid::s4u::Comm::test()`")
 273       .def("wait", &simgrid::s4u::Comm::wait, py::call_guard<GilScopedRelease>(),
 274            "Block until the completion of that communication, see :cpp:func:`simgrid::s4u::Comm::wait()`")
 275       .def("wait_all", &simgrid::s4u::Comm::wait_all, py::call_guard<GilScopedRelease>(),
 276            "Block until the completion of all communications in the list, see "
 277            ":cpp:func:`simgrid::s4u::Comm::wait_all()`")
 278       .def("wait_any", &simgrid::s4u::Comm::wait_any, py::call_guard<GilScopedRelease>(),
 279            "Block until the completion of any communication in the list and return the index of the terminated one, "
 280            "see :cpp:func:`simgrid::s4u::Comm::wait_any()`");
 281
 282   /* Class Exec */
 283   py::class_<simgrid::s4u::Exec, simgrid::s4u::ExecPtr>(m, "Exec",
 284                                                         "Execution, see :ref:`class s4u::Exec <API_s4u_Exec>`")
 285       .def_property_readonly("remaining",
 286                              [](simgrid::s4u::ExecPtr self) {
 287                                GilScopedRelease gil_guard;
 288                                return self->get_remaining();
 289                              },
 290                              "Amount of flops that remain to be computed until completion, see "
 291                              ":cpp:func:`simgrid::s4u::Exec::get_remaining()`")
 292       .def_property_readonly("remaining_ratio",
 293                              [](simgrid::s4u::ExecPtr self) {
 294                                GilScopedRelease gil_guard;
 295                                return self->get_remaining_ratio();
 296                              },
 297                              "Amount of work remaining until completion from 0 (completely done) to 1 (nothing done "
 298                              "yet). See :cpp:func:`simgrid::s4u::Exec::get_remaining_ratio()`")
 299       .def_property("host",
 300                     [](simgrid::s4u::ExecPtr self) {
 301                       simgrid::s4u::ExecSeqPtr seq = boost::dynamic_pointer_cast<simgrid::s4u::ExecSeq>(self);
 302                       if (seq != nullptr)
 303                         return seq->get_host();
 304                       xbt_throw_unimplemented(__FILE__, __LINE__,
 305                                               "host of parallel executions is not implemented in python yet.");
 306                     },
 307                     &simgrid::s4u::Exec::set_host,
 308                     "Host on which this execution runs. See :cpp:func:`simgrid::s4u::ExecSeq::get_host()`")
 309       .def("test", &simgrid::s4u::Exec::test, py::call_guard<GilScopedRelease>(),
 310            "Test whether the execution is terminated, see :cpp:func:`simgrid::s4u::Exec::test()`")
 311       .def("cancel", &simgrid::s4u::Exec::cancel, py::call_guard<GilScopedRelease>(),
 312            "Cancel that execution, see :cpp:func:`simgrid::s4u::Exec::cancel()`")
 313       .def("start", &simgrid::s4u::Exec::start, py::call_guard<GilScopedRelease>(),
 314            "Start that execution, see :cpp:func:`simgrid::s4u::Exec::start()`")
 315       .def("wait", &simgrid::s4u::Exec::wait, py::call_guard<GilScopedRelease>(),
 316            "Block until the completion of that execution, see :cpp:func:`simgrid::s4u::Exec::wait()`");
 317
 318   /* Class Actor */
 319   py::class_<simgrid::s4u::Actor, ActorPtr>(m, "Actor",
 320                                             "An actor is an independent stream of execution in your distributed "
 321                                             "application, see :ref:`class s4u::Actor <API_s4u_Actor>`")
 322       .def("create",
 323            [](py::str name, Host* host, py::object fun, py::args args) {
 324              fun.inc_ref();  // FIXME: why is this needed for tests like exec-async, exec-dvfs and exec-remote?
 325              args.inc_ref(); // FIXME: why is this needed for tests like actor-migrate?
 326              return simgrid::s4u::Actor::create(name, host, [fun, args]() {
 327                GilScopedAcquire py_context;
 328                try {
 329                  fun(*args);
 330                } catch (const py::error_already_set& ex) {
 331                  bool ffk = ex.matches(pyForcefulKillEx);
 332                  py_context.reset();
 333                  if (ffk) {
 334                    XBT_VERB("Actor killed");
 335                    /* Forward that ForcefulKill exception */
 336                    simgrid::ForcefulKillException::do_throw();
 337                  }
 338                  throw;
 339                }
 340              });
 341            },
 342            py::call_guard<GilScopedRelease>(), "Create an actor from a function or an object.")
 343       .def_property("host", &Actor::get_host,
 344                     [](Actor* a, Host* h) {
 345                       GilScopedRelease gil_guard;
 346                       a->set_host(h);
 347                     },
 348                     "The host on which this actor is located")
 349       .def_property_readonly("name", &Actor::get_cname, "The name of this actor.")
 350       .def_property_readonly("pid", &Actor::get_pid, "The PID (unique identifier) of this actor.")
 351       .def_property_readonly("ppid", &Actor::get_ppid,
 352                              "The PID (unique identifier) of the actor that created this one.")
 353       .def("by_pid", &Actor::by_pid, "Retrieve an actor by its PID")
 354       .def("daemonize", &Actor::daemonize, py::call_guard<GilScopedRelease>(),
 355            "This actor will be automatically terminated when the last non-daemon actor finishes (more info in the C++ "
 356            "documentation).")
 357       .def("is_daemon", &Actor::is_daemon,
 358            "Returns True if that actor is a daemon and will be terminated automatically when the last non-daemon actor "
 359            "terminates.")
 360       .def("join", py::overload_cast<double>(&Actor::join), py::call_guard<GilScopedRelease>(),
 361            "Wait for the actor to finish (more info in the C++ documentation).", py::arg("timeout"))
 362       .def("kill", &Actor::kill, py::call_guard<GilScopedRelease>(), "Kill that actor")
 363       .def("kill_all", &Actor::kill_all, py::call_guard<GilScopedRelease>(), "Kill all actors but the caller.")
 364       .def("self", &Actor::self, "Retrieves the current actor.")
 365       .def("is_suspended", &Actor::is_suspended, "Returns True if that actor is currently suspended.")
 366       .def("suspend", &Actor::suspend, py::call_guard<GilScopedRelease>(),
 367            "Suspend that actor, that is blocked until resume()ed by another actor.")
 368       .def("resume", &Actor::resume, py::call_guard<GilScopedRelease>(),
 369            "Resume that actor, that was previously suspend()ed.");
 370 }