src/bindings/python/simgrid_python.cpp

   1 /* Copyright (c) 2018-2021. 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 #ifndef NDEBUG
  17 /* Many tests are failing after pybind11 commit ad6bf5cd39ca64b4a9bf846b84b11c4c8df1c8e1 "Adding PyGILState_Check() in
  18  *  object_api<>::operator(). (#2919)".
  19  * See https://github.com/pybind/pybind11/commit/ad6bf5cd39ca64b4a9bf846b84b11c4c8df1c8e1
  20  *
  21  * The failing tests are mostly those with boost/raw/sysv contexts. As a workaround, define NDEBUG before pybind11
  22  * includes.
  23  */
  24 #define NDEBUG
  25 #define NDEBUG_LOCALLY_DEFINED
  26 #endif
  27
  28 #include <pybind11/pybind11.h> // Must come before our own stuff
  29
  30 #include <pybind11/functional.h>
  31 #include <pybind11/stl.h>
  32
  33 #ifdef NDEBUG_LOCALLY_DEFINED
  34 #undef NDEBUG_LOCALLY_DEFINED
  35 #undef NDEBUG
  36 #endif
  37
  38 #if defined(__GNUG__)
  39 #pragma GCC diagnostic pop
  40 #endif
  41
  42 #include "src/kernel/context/Context.hpp"
  43 #include <simgrid/Exception.hpp>
  44 #include <simgrid/s4u/Actor.hpp>
  45 #include <simgrid/s4u/Comm.hpp>
  46 #include <simgrid/s4u/Engine.hpp>
  47 #include <simgrid/s4u/Exec.hpp>
  48 #include <simgrid/s4u/Host.hpp>
  49 #include <simgrid/s4u/Mailbox.hpp>
  50 #include <simgrid/version.h>
  51
  52 #include <algorithm>
  53 #include <memory>
  54 #include <string>
  55 #include <vector>
  56
  57 namespace py = pybind11;
  58 using simgrid::s4u::Actor;
  59 using simgrid::s4u::ActorPtr;
  60 using simgrid::s4u::Engine;
  61 using simgrid::s4u::Host;
  62 using simgrid::s4u::Mailbox;
  63
  64 XBT_LOG_NEW_DEFAULT_CATEGORY(python, "python");
  65
  66 namespace {
  67
  68 std::string get_simgrid_version()
  69 {
  70   int major;
  71   int minor;
  72   int patch;
  73   sg_version_get(&major, &minor, &patch);
  74   return simgrid::xbt::string_printf("%i.%i.%i", major, minor, patch);
  75 }
  76
  77 /* Classes GilScopedAcquire and GilScopedRelease have the same purpose as pybind11::gil_scoped_acquire and
  78  * pybind11::gil_scoped_release.  Refer to the manual of pybind11 for details:
  79  * https://pybind11.readthedocs.io/en/stable/advanced/misc.html#global-interpreter-lock-gil
  80  *
  81  * The pybind11 versions are however too sophisticated (using TLS for example) and don't work well with all kinds of
  82  * contexts.
  83  * See also https://github.com/pybind/pybind11/issues/1276, which may be related.
  84  *
  85  * Briefly, GilScopedAcquire can be used on actor creation to acquire a new PyThreadState.  The PyThreadState has to be
  86  * released for context switches (i.e. before simcalls). That's the purpose of GilScopedRelease.
  87  *
  88  * Like their pybind11 counterparts, both classes use a RAII pattern.
  89  */
  90 class XBT_PRIVATE GilScopedAcquire {
  91   static PyThreadState* acquire()
  92   {
  93     PyThreadState* state = PyThreadState_New(PyInterpreterState_Head());
  94     PyEval_AcquireThread(state);
  95     return state;
  96   }
  97   static void release(PyThreadState* state)
  98   {
  99     PyEval_ReleaseThread(state);
 100     PyThreadState_Clear(state);
 101     PyThreadState_Delete(state);
 102   }
 103
 104   std::unique_ptr<PyThreadState, decltype(&release)> thread_state{acquire(), &release};
 105
 106 public:
 107   void reset() { thread_state.reset(); }
 108 };
 109
 110 class XBT_PRIVATE GilScopedRelease {
 111   std::unique_ptr<PyThreadState, decltype(&PyEval_RestoreThread)> thread_state{PyEval_SaveThread(),
 112                                                                                &PyEval_RestoreThread};
 113 };
 114
 115 } // namespace
 116
 117 PYBIND11_DECLARE_HOLDER_TYPE(T, boost::intrusive_ptr<T>)
 118
 119 PYBIND11_MODULE(simgrid, m)
 120 {
 121   m.doc() = "SimGrid userspace API";
 122
 123   m.attr("simgrid_version") = get_simgrid_version();
 124
 125   // Internal exception used to kill actors and sweep the RAII chimney (free objects living on the stack)
 126   static py::object pyForcefulKillEx(py::register_exception<simgrid::ForcefulKillException>(m, "ActorKilled"));
 127
 128   /* this_actor namespace */
 129   m.def_submodule("this_actor", "Bindings of the s4u::this_actor namespace.")
 130       .def(
 131           "info", [](const char* s) { XBT_INFO("%s", s); }, "Display a logging message of 'info' priority.")
 132       .def(
 133           "error", [](const char* s) { XBT_ERROR("%s", s); }, "Display a logging message of 'error' priority.")
 134       .def("execute", py::overload_cast<double, double>(&simgrid::s4u::this_actor::execute),
 135            py::call_guard<GilScopedRelease>(),
 136            "Block the current actor, computing the given amount of flops at the given priority.", py::arg("flops"),
 137            py::arg("priority") = 1)
 138       .def("exec_init", py::overload_cast<double>(&simgrid::s4u::this_actor::exec_init),
 139            py::call_guard<GilScopedRelease>())
 140       .def("get_host", &simgrid::s4u::this_actor::get_host, "Retrieves host on which the current actor is located")
 141       .def("set_host", &simgrid::s4u::this_actor::set_host, py::call_guard<GilScopedRelease>(),
 142            "Moves the current actor to another host.", py::arg("dest"))
 143       .def("sleep_for", static_cast<void (*)(double)>(&simgrid::s4u::this_actor::sleep_for),
 144            py::call_guard<GilScopedRelease>(), "Block the actor sleeping for that amount of seconds.",
 145            py::arg("duration"))
 146       .def("sleep_until", static_cast<void (*)(double)>(&simgrid::s4u::this_actor::sleep_until),
 147            py::call_guard<GilScopedRelease>(), "Block the actor sleeping until the specified timestamp.",
 148            py::arg("duration"))
 149       .def("suspend", &simgrid::s4u::this_actor::suspend, py::call_guard<GilScopedRelease>(),
 150            "Suspend the current actor, that is blocked until resume()ed by another actor.")
 151       .def("yield_", &simgrid::s4u::this_actor::yield, py::call_guard<GilScopedRelease>(), "Yield the actor")
 152       .def("exit", &simgrid::s4u::this_actor::exit, py::call_guard<GilScopedRelease>(), "kill the current actor")
 153       .def(
 154           "on_exit",
 155           [](py::object fun) {
 156             fun.inc_ref(); // FIXME: why is this needed for tests like actor-kill and actor-lifetime?
 157             simgrid::s4u::this_actor::on_exit([fun](bool /*failed*/) {
 158               GilScopedAcquire py_context; // need a new context for callback
 159               try {
 160                 fun();
 161               } catch (const py::error_already_set& e) {
 162                 std::string what = e.what();
 163                 py_context.reset();
 164                 xbt_die("Error while executing the on_exit lambda: %s", what.c_str());
 165               }
 166             });
 167           },
 168           py::call_guard<GilScopedRelease>(), "");
 169
 170   /* Class Engine */
 171   py::class_<Engine>(m, "Engine", "Simulation Engine")
 172       .def(py::init([](std::vector<std::string> args) {
 173         auto argc           = static_cast<int>(args.size());
 174         std::vector<char*> argv(args.size() + 1); // argv[argc] is nullptr
 175         std::transform(begin(args), end(args), begin(argv), [](std::string& s) { return &s.front(); });
 176         // Currently this can be dangling, we should wrap this somehow.
 177         return new simgrid::s4u::Engine(&argc, argv.data());
 178       }))
 179       .def_static("get_clock", &Engine::get_clock,
 180                   "The simulation time, ie the amount of simulated seconds since the simulation start.")
 181       .def("get_all_hosts", &Engine::get_all_hosts, "Returns the list of all hosts found in the platform")
 182       .def("load_platform", &Engine::load_platform, "Load a platform file describing the environment")
 183       .def("load_deployment", &Engine::load_deployment, "Load a deployment file and launch the actors that it contains")
 184       .def("run", &Engine::run, py::call_guard<GilScopedRelease>(), "Run the simulation")
 185       .def(
 186           "register_actor",
 187           [](Engine* e, const std::string& name, py::object fun_or_class) {
 188             e->register_actor(name, [fun_or_class](std::vector<std::string> args) {
 189               GilScopedAcquire py_context;
 190               try {
 191                 /* Convert the std::vector into a py::tuple */
 192                 py::tuple params(args.size() - 1);
 193                 for (size_t i = 1; i < args.size(); i++)
 194                   params[i - 1] = py::cast(args[i]);
 195
 196                 py::object res = fun_or_class(*params);
 197                 /* If I was passed a class, I just built an instance, so I need to call it now */
 198                 if (py::isinstance<py::function>(res))
 199                   res();
 200               } catch (const py::error_already_set& ex) {
 201                 bool ffk = ex.matches(pyForcefulKillEx);
 202                 py_context.reset();
 203                 if (ffk) {
 204                   XBT_VERB("Actor killed");
 205                   simgrid::ForcefulKillException::do_throw(); // Forward that ForcefulKill exception
 206                 }
 207                 throw;
 208               }
 209             });
 210           },
 211           "Registers the main function of an actor");
 212
 213   /* Class Host */
 214   py::class_<simgrid::s4u::Host, std::unique_ptr<Host, py::nodelete>>(m, "Host", "Simulated host")
 215       .def("by_name", &Host::by_name, "Retrieves a host from its name, or die")
 216       .def("get_pstate_count", &Host::get_pstate_count, "Retrieve the count of defined pstate levels")
 217       .def("get_pstate_speed", &Host::get_pstate_speed, "Retrieve the maximal speed at the given pstate")
 218       .def_property(
 219           "pstate", &Host::get_pstate,
 220           [](Host* h, int i) {
 221             GilScopedRelease gil_guard;
 222             h->set_pstate(i);
 223           },
 224           "The current pstate")
 225       .def("current", &Host::current, py::call_guard<GilScopedRelease>(),
 226            "Retrieves the host on which the running actor is located.")
 227       .def_property_readonly(
 228           "name",
 229           [](const Host* self) {
 230             return std::string(self->get_name().c_str()); // Convert from xbt::string because of MC
 231           },
 232           "The name of this host")
 233       .def_property_readonly(
 234           "load", &Host::get_load,
 235           "Returns the current computation load (in flops per second). This is the currently achieved speed.")
 236       .def_property_readonly(
 237           "speed", &Host::get_speed,
 238           "The peak computing speed in flops/s at the current pstate, taking the external load into account. "
 239           "This is the max potential speed.");
 240
 241   /* Class Mailbox */
 242   py::class_<simgrid::s4u::Mailbox, std::unique_ptr<Mailbox, py::nodelete>>(m, "Mailbox", "Mailbox")
 243       .def(
 244           "__str__", [](const Mailbox* self) { return std::string("Mailbox(") + self->get_cname() + ")"; },
 245           "Textual representation of the Mailbox`")
 246       .def("by_name", &Mailbox::by_name, py::call_guard<GilScopedRelease>(), "Retrieve a Mailbox from its name")
 247       .def_property_readonly(
 248           "name",
 249           [](const Mailbox* self) {
 250             return std::string(self->get_name().c_str()); // Convert from xbt::string because of MC
 251           },
 252           "The name of that mailbox")
 253       .def(
 254           "put",
 255           [](Mailbox* self, py::object data, int size) {
 256             data.inc_ref();
 257             self->put(data.ptr(), size);
 258           },
 259           py::call_guard<GilScopedRelease>(), "Blocking data transmission")
 260       .def(
 261           "put_async",
 262           [](Mailbox* self, py::object data, int size) {
 263             data.inc_ref();
 264             return self->put_async(data.ptr(), size);
 265           },
 266           py::call_guard<GilScopedRelease>(), "Non-blocking data transmission")
 267       .def(
 268           "get",
 269           [](Mailbox* self) {
 270             py::object data = pybind11::reinterpret_steal<py::object>(self->get<PyObject>());
 271             // data.dec_ref(); // FIXME: why does it break python-actor-create?
 272             return data;
 273           },
 274           py::call_guard<GilScopedRelease>(), "Blocking data reception")
 275       .def("set_receiver",
 276          [](Mailbox* self, ActorPtr actor) {
 277            self->set_receiver(actor);
 278          },
 279          py::call_guard<GilScopedRelease>(),
 280          "Sets the actor as permanent receiver");
 281
 282   /* Class Comm */
 283   py::class_<simgrid::s4u::Comm, simgrid::s4u::CommPtr>(m, "Comm", "Communication")
 284       .def("test", &simgrid::s4u::Comm::test, py::call_guard<GilScopedRelease>(),
 285            "Test whether the communication is terminated.")
 286       .def("wait", &simgrid::s4u::Comm::wait, py::call_guard<GilScopedRelease>(),
 287            "Block until the completion of that communication.")
 288       // use py::overload_cast for wait_all/wait_any, until the overload marked XBT_ATTRIB_DEPRECATED_v332 is removed
 289       .def_static("wait_all",
 290                   py::overload_cast<const std::vector<simgrid::s4u::CommPtr>&>(&simgrid::s4u::Comm::wait_all),
 291                   py::call_guard<GilScopedRelease>(), "Block until the completion of all communications in the list.")
 292       .def_static(
 293           "wait_any", py::overload_cast<const std::vector<simgrid::s4u::CommPtr>&>(&simgrid::s4u::Comm::wait_any),
 294           py::call_guard<GilScopedRelease>(),
 295           "Block until the completion of any communication in the list and return the index of the terminated one.");
 296
 297   /* Class Exec */
 298   py::class_<simgrid::s4u::Exec, simgrid::s4u::ExecPtr>(m, "Exec", "Execution")
 299       .def_property_readonly(
 300           "remaining",
 301           [](simgrid::s4u::ExecPtr self) {
 302             GilScopedRelease gil_guard;
 303             return self->get_remaining();
 304           },
 305           "Amount of flops that remain to be computed until completion.")
 306       .def_property_readonly(
 307           "remaining_ratio",
 308           [](simgrid::s4u::ExecPtr self) {
 309             GilScopedRelease gil_guard;
 310             return self->get_remaining_ratio();
 311           },
 312           "Amount of work remaining until completion from 0 (completely done) to 1 (nothing done "
 313           "yet).")
 314       .def_property("host", &simgrid::s4u::Exec::get_host, &simgrid::s4u::Exec::set_host,
 315                     "Host on which this execution runs. Only the first host is returned for parallel executions.")
 316       .def("test", &simgrid::s4u::Exec::test, py::call_guard<GilScopedRelease>(),
 317            "Test whether the execution is terminated.")
 318       .def("cancel", &simgrid::s4u::Exec::cancel, py::call_guard<GilScopedRelease>(), "Cancel that execution.")
 319       .def("start", &simgrid::s4u::Exec::start, py::call_guard<GilScopedRelease>(), "Start that execution.")
 320       .def("wait", &simgrid::s4u::Exec::wait, py::call_guard<GilScopedRelease>(),
 321            "Block until the completion of that execution.");
 322
 323   /* Class Actor */
 324   py::class_<simgrid::s4u::Actor, ActorPtr>(m, "Actor",
 325                                             "An actor is an independent stream of execution in your distributed "
 326                                             "application")
 327       .def(
 328           "create",
 329           [](py::str name, Host* host, py::object fun, py::args args) {
 330             fun.inc_ref();  // FIXME: why is this needed for tests like exec-async, exec-dvfs and exec-remote?
 331             args.inc_ref(); // FIXME: why is this needed for tests like actor-migrate?
 332             return simgrid::s4u::Actor::create(name, host, [fun, args]() {
 333               GilScopedAcquire py_context;
 334               try {
 335                 fun(*args);
 336               } catch (const py::error_already_set& ex) {
 337                 bool ffk = ex.matches(pyForcefulKillEx);
 338                 py_context.reset();
 339                 if (ffk) {
 340                   XBT_VERB("Actor killed");
 341                   simgrid::ForcefulKillException::do_throw(); // Forward that ForcefulKill exception
 342                 }
 343                 throw;
 344               }
 345             });
 346           },
 347           py::call_guard<GilScopedRelease>(), "Create an actor from a function or an object.")
 348       .def_property(
 349           "host", &Actor::get_host,
 350           [](Actor* a, Host* h) {
 351             GilScopedRelease gil_guard;
 352             a->set_host(h);
 353           },
 354           "The host on which this actor is located")
 355       .def_property_readonly("name", &Actor::get_cname, "The name of this actor.")
 356       .def_property_readonly("pid", &Actor::get_pid, "The PID (unique identifier) of this actor.")
 357       .def_property_readonly("ppid", &Actor::get_ppid,
 358                              "The PID (unique identifier) of the actor that created this one.")
 359       .def("by_pid", &Actor::by_pid, "Retrieve an actor by its PID")
 360       .def("daemonize", &Actor::daemonize, py::call_guard<GilScopedRelease>(),
 361            "This actor will be automatically terminated when the last non-daemon actor finishes (more info in the C++ "
 362            "documentation).")
 363       .def("is_daemon", &Actor::is_daemon,
 364            "Returns True if that actor is a daemon and will be terminated automatically when the last non-daemon actor "
 365            "terminates.")
 366       .def("join", py::overload_cast<double>(&Actor::join, py::const_), py::call_guard<GilScopedRelease>(),
 367            "Wait for the actor to finish (more info in the C++ documentation).", py::arg("timeout"))
 368       .def("kill", &Actor::kill, py::call_guard<GilScopedRelease>(), "Kill that actor")
 369       .def("kill_all", &Actor::kill_all, py::call_guard<GilScopedRelease>(), "Kill all actors but the caller.")
 370       .def("self", &Actor::self, "Retrieves the current actor.")
 371       .def("is_suspended", &Actor::is_suspended, "Returns True if that actor is currently suspended.")
 372       .def("suspend", &Actor::suspend, py::call_guard<GilScopedRelease>(),
 373            "Suspend that actor, that is blocked until resume()ed by another actor.")
 374       .def("resume", &Actor::resume, py::call_guard<GilScopedRelease>(),
 375            "Resume that actor, that was previously suspend()ed.");
 376 }