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Remove ancient hack.
[simgrid.git] / src / bindings / python / simgrid_python.cpp
index e1c42ed..62c395a 100644 (file)
@@ -1,27 +1,13 @@
-/* Copyright (c) 2018-2022. The SimGrid Team. All rights reserved.          */
+/* Copyright (c) 2018-2023. The SimGrid Team. All rights reserved.          */
 
 /* This program is free software; you can redistribute it and/or modify it
  * under the terms of the license (GNU LGPL) which comes with this package. */
 
-#ifdef _WIN32
-#warning Try to work around https://bugs.python.org/issue11566
-#define _hypot hypot
-#endif
-
-#if defined(__GNUG__)
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wunused-value"
-#endif
-
 #include <pybind11/pybind11.h> // Must come before our own stuff
 
 #include <pybind11/functional.h>
 #include <pybind11/stl.h>
 
-#if defined(__GNUG__)
-#pragma GCC diagnostic pop
-#endif
-
 #include "simgrid/kernel/ProfileBuilder.hpp"
 #include "simgrid/kernel/routing/NetPoint.hpp"
 #include <simgrid/Exception.hpp>
@@ -123,14 +109,12 @@ PYBIND11_MODULE(simgrid, m)
            py::call_guard<py::gil_scoped_release>())
       .def("exec_async", py::overload_cast<double>(&simgrid::s4u::this_actor::exec_async),
            py::call_guard<py::gil_scoped_release>())
-      .def("parallel_execute", &simgrid::s4u::this_actor::parallel_execute,
-           py::call_guard<py::gil_scoped_release>(),
+      .def("parallel_execute", &simgrid::s4u::this_actor::parallel_execute, py::call_guard<py::gil_scoped_release>(),
            "Run a parallel task (requires the 'ptask_L07' model)")
       .def("exec_init",
            py::overload_cast<const std::vector<simgrid::s4u::Host*>&, const std::vector<double>&,
-           const std::vector<double>&>  (&simgrid::s4u::this_actor::exec_init),
-           py::call_guard<py::gil_scoped_release>(),
-           "Initiate a parallel task (requires the 'ptask_L07' model)")
+                             const std::vector<double>&>(&simgrid::s4u::this_actor::exec_init),
+           py::call_guard<py::gil_scoped_release>(), "Initiate a parallel task (requires the 'ptask_L07' model)")
       .def("get_host", &simgrid::s4u::this_actor::get_host, "Retrieves host on which the current actor is located")
       .def("set_host", &simgrid::s4u::this_actor::set_host, py::call_guard<py::gil_scoped_release>(),
            "Moves the current actor to another host.", py::arg("dest"))
@@ -146,19 +130,19 @@ PYBIND11_MODULE(simgrid, m)
       .def("exit", &simgrid::s4u::this_actor::exit, py::call_guard<py::gil_scoped_release>(), "kill the current actor")
       .def(
           "on_exit",
-          [](py::object cb) {
-            py::function fun = py::reinterpret_borrow<py::function>(cb);
-            fun.inc_ref(); // FIXME: why is this needed for tests like actor-kill and actor-lifetime?
-            simgrid::s4u::this_actor::on_exit([fun](bool failed) {
-              py::gil_scoped_acquire py_context; // need a new context for callback
+          [](py::object fun) {
+            fun.inc_ref(); // keep alive after return
+            const py::gil_scoped_release gil_release;
+            simgrid::s4u::this_actor::on_exit([fun_p = fun.ptr()](bool failed) {
+              const py::gil_scoped_acquire py_context; // need a new context for callback
               try {
+                const auto fun = py::reinterpret_borrow<py::function>(fun_p);
                 fun(failed);
               } catch (const py::error_already_set& e) {
                 xbt_die("Error while executing the on_exit lambda: %s", e.what());
               }
             });
           },
-          py::call_guard<py::gil_scoped_release>(),
           "Define a lambda to be called when the actor ends. It takes a bool parameter indicating whether the actor "
           "was killed. If False, the actor finished peacefully.")
       .def("get_pid", &simgrid::s4u::this_actor::get_pid, "Retrieves PID of the current actor")
@@ -195,7 +179,7 @@ PYBIND11_MODULE(simgrid, m)
                           "get_all_hosts() is deprecated and  will be dropped after v3.33, use all_hosts instead.", 1);
              return self.attr("all_hosts");
            })
-      .def("host_by_name", &Engine::host_by_name_or_null, py::call_guard<py::gil_scoped_release>(),
+      .def("host_by_name", &Engine::host_by_name_or_null,
            "Retrieve a host by its name, or None if it does not exist in the platform.")
       .def_property_readonly("all_hosts", &Engine::get_all_hosts, "Returns the list of all hosts found in the platform")
       .def("get_all_links",
@@ -231,10 +215,8 @@ PYBIND11_MODULE(simgrid, m)
            "Change one of SimGrid's configurations")
       .def("load_platform", &Engine::load_platform, "Load a platform file describing the environment")
       .def("load_deployment", &Engine::load_deployment, "Load a deployment file and launch the actors that it contains")
-      .def("mailbox_by_name_or_create", &Engine::mailbox_by_name_or_create,
-           py::call_guard<py::gil_scoped_release>(),
-           py::arg("name"),
-           "Find a mailbox from its name or create one if it does not exist")
+      .def("mailbox_by_name_or_create", &Engine::mailbox_by_name_or_create, py::call_guard<py::gil_scoped_release>(),
+           py::arg("name"), "Find a mailbox from its name or create one if it does not exist")
       .def("run", &Engine::run, py::call_guard<py::gil_scoped_release>(), "Run the simulation until its end")
       .def("run_until", py::overload_cast<double>(&Engine::run_until, py::const_),
            py::call_guard<py::gil_scoped_release>(), "Run the simulation until the given date",
@@ -242,14 +224,17 @@ PYBIND11_MODULE(simgrid, m)
       .def(
           "register_actor",
           [](Engine* e, const std::string& name, py::object fun_or_class) {
-            e->register_actor(name, [fun_or_class](std::vector<std::string> args) {
-              py::gil_scoped_acquire py_context;
+            fun_or_class.inc_ref(); // keep alive after return
+            const py::gil_scoped_release gil_release;
+            e->register_actor(name, [fun_or_class_p = fun_or_class.ptr()](std::vector<std::string> args) {
+              const py::gil_scoped_acquire py_context;
               try {
                 /* Convert the std::vector into a py::tuple */
                 py::tuple params(args.size() - 1);
                 for (size_t i = 1; i < args.size(); i++)
                   params[i - 1] = py::cast(args[i]);
 
+                const auto fun_or_class = py::reinterpret_borrow<py::object>(fun_or_class_p);
                 py::object res = fun_or_class(*params);
                 /* If I was passed a class, I just built an instance, so I need to call it now */
                 if (py::isinstance<py::function>(res))
@@ -324,9 +309,8 @@ PYBIND11_MODULE(simgrid, m)
       .def_property_readonly("netpoint", &simgrid::s4u::NetZone::get_netpoint,
                              "Retrieve the netpoint associated to this zone")
       .def("seal", &simgrid::s4u::NetZone::seal, "Seal this NetZone")
-      .def_property_readonly(
-          "name", [](const simgrid::s4u::NetZone* self) { return self->get_name(); },
-          "The name of this network zone (read-only property).");
+      .def_property_readonly("name", &simgrid::s4u::NetZone::get_name,
+                             "The name of this network zone (read-only property).");
 
   /* Class ClusterCallbacks */
   py::class_<simgrid::s4u::ClusterCallbacks>(m, "ClusterCallbacks", "Callbacks used to create cluster zones")
@@ -410,8 +394,7 @@ PYBIND11_MODULE(simgrid, m)
                  "get_pstate_speed() is deprecated and  will be dropped after v3.33, use pstate_speed instead.", 1);
              return self.attr("pstate_speed")(state);
            })
-      .def("pstate_speed", &Host::get_pstate_speed, py::call_guard<py::gil_scoped_release>(),
-           "Retrieve the maximal speed at the given pstate")
+      .def("pstate_speed", &Host::get_pstate_speed, "Retrieve the maximal speed at the given pstate")
       .def("get_netpoint",
            [](py::object self) // XBT_ATTRIB_DEPRECATED_v334
            {
@@ -429,13 +412,9 @@ PYBIND11_MODULE(simgrid, m)
                           1);
              self.attr("core_count")(count);
            })
-      .def_property(
-          "core_count", &Host::get_core_count,
-          [](Host* h, int count) {
-            py::gil_scoped_release gil_guard;
-            return h->set_core_count(count);
-          },
-          "Manage the number of cores in the CPU")
+      .def_property("core_count", &Host::get_core_count,
+                    py::cpp_function(&Host::set_core_count, py::call_guard<py::gil_scoped_release>()),
+                    "Manage the number of cores in the CPU")
       .def("set_coordinates", &Host::set_coordinates, py::call_guard<py::gil_scoped_release>(),
            "Set the coordinates of this host")
       .def("set_sharing_policy", &simgrid::s4u::Host::set_sharing_policy, py::call_guard<py::gil_scoped_release>(),
@@ -446,21 +425,12 @@ PYBIND11_MODULE(simgrid, m)
            py::overload_cast<const std::string&, const std::string&, const std::string&>(&Host::create_disk),
            py::call_guard<py::gil_scoped_release>(), "Create a disk")
       .def("seal", &Host::seal, py::call_guard<py::gil_scoped_release>(), "Seal this host")
-      .def_property(
-          "pstate", &Host::get_pstate,
-          [](Host* h, int i) {
-            py::gil_scoped_release gil_guard;
-            h->set_pstate(i);
-          },
-          "The current pstate (read/write property).")
+      .def_property("pstate", &Host::get_pstate,
+                    py::cpp_function(&Host::set_pstate, py::call_guard<py::gil_scoped_release>()),
+                    "The current pstate (read/write property).")
       .def_static("current", &Host::current, py::call_guard<py::gil_scoped_release>(),
-           "Retrieves the host on which the running actor is located.")
-      .def_property_readonly(
-          "name",
-          [](const Host* self) {
-            return std::string(self->get_name().c_str()); // Convert from xbt::string because of MC
-          },
-          "The name of this host (read-only property).")
+                  "Retrieves the host on which the running actor is located.")
+      .def_property_readonly("name", &Host::get_name, "The name of this host (read-only property).")
       .def_property_readonly("load", &Host::get_load,
                              "Returns the current computation load (in flops per second), NOT taking the external load "
                              "into account. This is the currently achieved speed (read-only property).")
@@ -475,17 +445,19 @@ PYBIND11_MODULE(simgrid, m)
       .def_static(
           "on_creation_cb",
           [](py::object cb) {
-            Host::on_creation_cb([cb](Host& h) {
-              py::function fun = py::reinterpret_borrow<py::function>(cb);
-              py::gil_scoped_acquire py_context; // need a new context for callback
+            cb.inc_ref(); // keep alive after return
+            const py::gil_scoped_release gil_release;
+            Host::on_creation_cb([cb_p = cb.ptr()](Host& h) {
+              const py::gil_scoped_acquire py_context; // need a new context for callback
               try {
+                const auto fun = py::reinterpret_borrow<py::function>(cb_p);
                 fun(&h);
               } catch (const py::error_already_set& e) {
                 xbt_die("Error while executing the on_creation lambda : %s", e.what());
               }
             });
           },
-          py::call_guard<py::gil_scoped_release>(), "");
+          "");
 
   py::enum_<simgrid::s4u::Host::SharingPolicy>(host, "SharingPolicy")
       .value("NONLINEAR", simgrid::s4u::Host::SharingPolicy::NONLINEAR)
@@ -507,9 +479,7 @@ PYBIND11_MODULE(simgrid, m)
            "Set sharing policy for this disk", py::arg("op"), py::arg("policy"),
            py::arg("cb") = simgrid::s4u::NonLinearResourceCb())
       .def("seal", &simgrid::s4u::Disk::seal, py::call_guard<py::gil_scoped_release>(), "Seal this disk")
-      .def_property_readonly(
-          "name", [](const simgrid::s4u::Disk* self) { return self->get_name(); },
-          "The name of this disk (read-only property).");
+      .def_property_readonly("name", &simgrid::s4u::Disk::get_name, "The name of this disk (read-only property).");
   py::enum_<simgrid::s4u::Disk::SharingPolicy>(disk, "SharingPolicy")
       .value("NONLINEAR", simgrid::s4u::Disk::SharingPolicy::NONLINEAR)
       .value("LINEAR", simgrid::s4u::Disk::SharingPolicy::LINEAR)
@@ -602,12 +572,7 @@ PYBIND11_MODULE(simgrid, m)
            "Set level of communication speed of given host on this Wi-Fi link")
       .def_static("by_name", &Link::by_name, "Retrieves a Link from its name, or dies")
       .def("seal", &Link::seal, py::call_guard<py::gil_scoped_release>(), "Seal this link")
-      .def_property_readonly(
-          "name",
-          [](const Link* self) {
-            return std::string(self->get_name().c_str()); // Convert from xbt::string because of MC
-          },
-          "The name of this link")
+      .def_property_readonly("name", &Link::get_name, "The name of this link")
       .def_property_readonly("bandwidth", &Link::get_bandwidth,
                              "The bandwidth (in bytes per second) (read-only property).")
       .def_property_readonly("latency", &Link::get_latency, "The latency (in seconds) (read-only property).");
@@ -654,56 +619,47 @@ PYBIND11_MODULE(simgrid, m)
   py::class_<simgrid::s4u::Mailbox, std::unique_ptr<Mailbox, py::nodelete>>(
       m, "Mailbox", "Mailbox. See the C++ documentation for details.")
       .def(
-          "__str__", [](const Mailbox* self) { return std::string("Mailbox(") + self->get_cname() + ")"; },
+          "__str__", [](const Mailbox* self) { return "Mailbox(" + self->get_name() + ")"; },
           "Textual representation of the Mailbox`")
-      .def_static("by_name", &Mailbox::by_name,
-                  py::call_guard<py::gil_scoped_release>(),
-                  py::arg("name"),
+      .def_static("by_name", &Mailbox::by_name, py::call_guard<py::gil_scoped_release>(), py::arg("name"),
                   "Retrieve a Mailbox from its name")
-      .def_property_readonly(
-          "name",
-          [](const Mailbox* self) {
-            return std::string(self->get_name().c_str()); // Convert from xbt::string because of MC
-          },
-          "The name of that mailbox (read-only property).")
-      .def_property_readonly("ready", &Mailbox::ready, py::call_guard<py::gil_scoped_release>(),
+      .def_property_readonly("name", &Mailbox::get_name, "The name of that mailbox (read-only property).")
+      .def_property_readonly("ready", &Mailbox::ready,
                              "Check if there is a communication ready to be consumed from a mailbox.")
       .def(
           "put",
           [](Mailbox* self, py::object data, uint64_t size, double timeout) {
-            data.inc_ref();
-            self->put(data.ptr(), size, timeout);
+            auto* data_ptr = data.inc_ref().ptr();
+            const py::gil_scoped_release gil_release;
+            self->put(data_ptr, size, timeout);
           },
-          py::call_guard<py::gil_scoped_release>(), "Blocking data transmission with a timeout")
+          "Blocking data transmission with a timeout")
       .def(
           "put",
           [](Mailbox* self, py::object data, uint64_t size) {
-            data.inc_ref();
-            self->put(data.ptr(), size);
+            auto* data_ptr = data.inc_ref().ptr();
+            const py::gil_scoped_release gil_release;
+            self->put(data_ptr, size);
           },
-          py::call_guard<py::gil_scoped_release>(), "Blocking data transmission")
+          "Blocking data transmission")
       .def(
           "put_async",
           [](Mailbox* self, py::object data, uint64_t size) {
-            data.inc_ref();
-            return self->put_async(data.ptr(), size);
+            auto* data_ptr = data.inc_ref().ptr();
+            const py::gil_scoped_release gil_release;
+            return self->put_async(data_ptr, size);
           },
-          py::call_guard<py::gil_scoped_release>(), "Non-blocking data transmission")
+          "Non-blocking data transmission")
       .def(
           "put_init",
           [](Mailbox* self, py::object data, uint64_t size) {
-            data.inc_ref();
-            return self->put_init(data.ptr(), size);
+            auto* data_ptr = data.inc_ref().ptr();
+            const py::gil_scoped_release gil_release;
+            return self->put_init(data_ptr, size);
           },
-          py::call_guard<py::gil_scoped_release>(),
           "Creates (but don’t start) a data transmission to that mailbox.")
       .def(
-          "get",
-          [](Mailbox* self) {
-            py::object data = py::reinterpret_steal<py::object>(self->get<PyObject>());
-            // data.dec_ref(); // FIXME: why does it break python-actor-create?
-            return data;
-          },
+          "get", [](Mailbox* self) { return py::reinterpret_steal<py::object>(self->get<PyObject>()); },
           py::call_guard<py::gil_scoped_release>(), "Blocking data reception")
       .def(
           "get_async",
@@ -714,9 +670,8 @@ PYBIND11_MODULE(simgrid, m)
           },
           py::call_guard<py::gil_scoped_release>(),
           "Non-blocking data reception. Use data.get() to get the python object after the communication has finished")
-      .def(
-          "set_receiver", [](Mailbox* self, ActorPtr actor) { self->set_receiver(actor); },
-          py::call_guard<py::gil_scoped_release>(), "Sets the actor as permanent receiver");
+      .def("set_receiver", &Mailbox::set_receiver, py::call_guard<py::gil_scoped_release>(),
+           "Sets the actor as permanent receiver");
 
   /* Class PyGetAsync */
   py::class_<PyGetAsync>(m, "PyGetAsync", "Wrapper for async get communications")
@@ -735,7 +690,7 @@ PYBIND11_MODULE(simgrid, m)
                              "Retrieve the mailbox on which this comm acts.")
       .def_property_readonly("sender", &Comm::get_sender,
                              py::call_guard<py::gil_scoped_release>())
-      .def_property_readonly("state_str", [](const Comm* self){ return std::string(self->get_state_str()); },
+      .def_property_readonly("state_str", &Comm::get_state_str,
                              py::call_guard<py::gil_scoped_release>(),
                              "Retrieve the Comm state as string")
       .def_property_readonly("remaining",  &Comm::get_remaining,
@@ -753,19 +708,15 @@ PYBIND11_MODULE(simgrid, m)
       .def("set_rate", &Comm::set_rate, py::call_guard<py::gil_scoped_release>(),
            py::arg("rate"),
            "Sets the maximal communication rate (in byte/sec). Must be done before start")
-      .def("cancel", [](Comm* self){ return self->cancel(); },
-           py::call_guard<py::gil_scoped_release>(), py::return_value_policy::reference_internal,
-           "Cancel the activity.")
-      .def("start", [](Comm* self){ return self->start(); },
-           py::call_guard<py::gil_scoped_release>(), py::return_value_policy::reference_internal,
+      .def("cancel", &Comm::cancel, py::call_guard<py::gil_scoped_release>(),
+           py::return_value_policy::reference_internal, "Cancel the activity.")
+      .def("start", &Comm::start, py::call_guard<py::gil_scoped_release>(), py::return_value_policy::reference_internal,
            "Starts a previously created activity. This function is optional: you can call wait() even if you didn't "
            "call start()")
-      .def("suspend", [](Comm* self){ return self->suspend(); },
-          py::call_guard<py::gil_scoped_release>(), py::return_value_policy::reference_internal,
-          "Suspend the activity.")
-      .def("resume", [](Comm* self){ return self->resume(); },
-          py::call_guard<py::gil_scoped_release>(), py::return_value_policy::reference_internal,
-          "Resume the activity.")
+      .def("suspend", &Comm::suspend, py::call_guard<py::gil_scoped_release>(),
+           py::return_value_policy::reference_internal, "Suspend the activity.")
+      .def("resume", &Comm::resume, py::call_guard<py::gil_scoped_release>(),
+           py::return_value_policy::reference_internal, "Resume the activity.")
       .def("test", &Comm::test, py::call_guard<py::gil_scoped_release>(),
            "Test whether the communication is terminated.")
       .def("wait", &Comm::wait, py::call_guard<py::gil_scoped_release>(),
@@ -776,8 +727,7 @@ PYBIND11_MODULE(simgrid, m)
       .def("wait_until", &Comm::wait_until, py::call_guard<py::gil_scoped_release>(),
            py::arg("time_limit"),
            "Block until the completion of that communication, or raises TimeoutException after the specified time.")
-      .def("detach", [](Comm* self) { return self->detach(); },
-           py::return_value_policy::reference_internal,
+      .def("detach", py::overload_cast<>(&Comm::detach), py::return_value_policy::reference_internal,
            py::call_guard<py::gil_scoped_release>(),
            "Start the comm, and ignore its result. It can be completely forgotten after that.")
       .def_static("sendto", &Comm::sendto, py::call_guard<py::gil_scoped_release>(),
@@ -828,21 +778,12 @@ PYBIND11_MODULE(simgrid, m)
 
   /* Class Exec */
   py::class_<simgrid::s4u::Exec, simgrid::s4u::ExecPtr>(m, "Exec", "Execution. See the C++ documentation for details.")
-      .def_property_readonly(
-          "remaining",
-          [](simgrid::s4u::ExecPtr self) {
-            py::gil_scoped_release gil_guard;
-            return self->get_remaining();
-          },
-          "Amount of flops that remain to be computed until completion (read-only property).")
-      .def_property_readonly(
-          "remaining_ratio",
-          [](simgrid::s4u::ExecPtr self) {
-            py::gil_scoped_release gil_guard;
-            return self->get_remaining_ratio();
-          },
-          "Amount of work remaining until completion from 0 (completely done) to 1 (nothing done "
-          "yet) (read-only property).")
+      .def_property_readonly("remaining", &simgrid::s4u::Exec::get_remaining, py::call_guard<py::gil_scoped_release>(),
+                             "Amount of flops that remain to be computed until completion (read-only property).")
+      .def_property_readonly("remaining_ratio", &simgrid::s4u::Exec::get_remaining_ratio,
+                             py::call_guard<py::gil_scoped_release>(),
+                             "Amount of work remaining until completion from 0 (completely done) to 1 (nothing done "
+                             "yet) (read-only property).")
       .def_property("host", &simgrid::s4u::Exec::get_host, &simgrid::s4u::Exec::set_host,
                     "Host on which this execution runs. Only the first host is returned for parallel executions. "
                     "Changing this value migrates the execution.")
@@ -876,8 +817,9 @@ PYBIND11_MODULE(simgrid, m)
                              "Check whether trying to acquire the semaphore would block (in other word, checks whether "
                              "this semaphore has capacity).")
       // Allow semaphores to be automatically acquired/released with a context manager: `with semaphore: ...`
-      .def("__enter__", [](Semaphore* self){ self->acquire(); }, py::call_guard<py::gil_scoped_release>())
-      .def("__exit__", [](Semaphore* self){ self->release(); }, py::call_guard<py::gil_scoped_release>());
+      .def("__enter__", &Semaphore::acquire, py::call_guard<py::gil_scoped_release>())
+      .def("__exit__",
+           [](Semaphore* self, const py::object&, const py::object&, const py::object&) { self->release(); });
 
   /* Class Mutex */
   py::class_<Mutex, MutexPtr>(m, "Mutex",
@@ -889,9 +831,9 @@ PYBIND11_MODULE(simgrid, m)
            "Try to acquire the mutex. Return true if the mutex was acquired, false otherwise.")
       .def("unlock", &Mutex::unlock, py::call_guard<py::gil_scoped_release>(), "Release the mutex.")
       // Allow mutexes to be automatically acquired/released with a context manager: `with mutex: ...`
-      .def("__enter__", [](Mutex* self){ self->lock(); }, py::call_guard<py::gil_scoped_release>())
+      .def("__enter__", &Mutex::lock, py::call_guard<py::gil_scoped_release>())
       .def("__exit__", [](Mutex* self, const py::object&, const py::object&, const py::object&) { self->unlock(); },
-          py::call_guard<py::gil_scoped_release>());
+           py::call_guard<py::gil_scoped_release>());
 
   /* Class Barrier */
   py::class_<Barrier, BarrierPtr>(m, "Barrier",
@@ -908,12 +850,15 @@ PYBIND11_MODULE(simgrid, m)
                                             "application. See the C++ documentation for details.")
       .def(
           "create",
-          [](py::str name, Host* h, py::object fun, py::args args) {
-            fun.inc_ref();  // FIXME: why is this needed for tests like exec-async, exec-dvfs and exec-remote?
-            args.inc_ref(); // FIXME: why is this needed for tests like actor-migrate?
-            return simgrid::s4u::Actor::create(name, h, [fun, args]() {
-              py::gil_scoped_acquire py_context;
+          [](const std::string& name, Host* h, py::object fun, py::args args) {
+            fun.inc_ref();  // keep alive after return
+            args.inc_ref(); // keep alive after return
+            const py::gil_scoped_release gil_release;
+            return simgrid::s4u::Actor::create(name, h, [fun_p = fun.ptr(), args_p = args.ptr()]() {
+              const py::gil_scoped_acquire py_context;
               try {
+                const auto fun  = py::reinterpret_borrow<py::object>(fun_p);
+                const auto args = py::reinterpret_borrow<py::args>(args_p);
                 fun(*args);
               } catch (const py::error_already_set& ex) {
                 if (ex.matches(pyForcefulKillEx)) {
@@ -924,14 +869,9 @@ PYBIND11_MODULE(simgrid, m)
               }
             });
           },
-          py::call_guard<py::gil_scoped_release>(),
           "Create an actor from a function or an object. See the :ref:`example <s4u_ex_actors_create>`.")
       .def_property(
-          "host", &Actor::get_host,
-          [](Actor* a, Host* h) {
-            py::gil_scoped_release gil_guard;
-            a->set_host(h);
-          },
+          "host", &Actor::get_host, py::cpp_function(&Actor::set_host, py::call_guard<py::gil_scoped_release>()),
           "The host on which this actor is located. Changing this value migrates the actor.\n\n"
           "If the actor is currently blocked on an execution activity, the activity is also migrated to the new host. "
           "If it’s blocked on another kind of activity, an error is raised as the mandated code is not written yet. "
@@ -960,5 +900,6 @@ PYBIND11_MODULE(simgrid, m)
            "Suspend that actor, that is blocked until resume()ed by another actor.")
       .def("resume", &Actor::resume, py::call_guard<py::gil_scoped_release>(),
            "Resume that actor, that was previously suspend()ed.")
-      .def_static("kill_all", &Actor::kill_all, py::call_guard<py::gil_scoped_release>(), "Kill all actors but the caller.");
+      .def_static("kill_all", &Actor::kill_all, py::call_guard<py::gil_scoped_release>(),
+                  "Kill all actors but the caller.");
 }