-/* Copyright (c) 2007-2018. The SimGrid Team.
+/* Copyright (c) 2007-2021. The SimGrid Team.
* All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
#include <xbt/functional.hpp>
#include <xbt/future.hpp>
#include <xbt/signal.hpp>
+#include <xbt/utility.hpp>
+#include <boost/heap/fibonacci_heap.hpp>
#include <string>
#include <unordered_map>
-XBT_PUBLIC void simcall_run_kernel(std::function<void()> const& code);
+XBT_PUBLIC void simcall_run_kernel(std::function<void()> const& code, simgrid::mc::SimcallInspector* t);
+XBT_PUBLIC void simcall_run_blocking(std::function<void()> const& code, simgrid::mc::SimcallInspector* t);
-/** Execute some code in the kernel and block
+namespace simgrid {
+namespace kernel {
+namespace actor {
+
+/** Execute some code in kernel context on behalf of the user code.
+ *
+ * Every modification of the environment must be protected this way: every setter, constructor and similar.
+ * Getters don't have to be protected this way.
*
- * run_blocking() is a generic blocking simcall. It is given a callback
- * which is executed immediately in the SimGrid kernel. The callback is
- * responsible for setting the suitable logic for waking up the process
- * when needed.
+ * This allows deterministic parallel simulation without any locking, even if almost nobody uses parallel simulation in
+ * SimGrid. More interestingly it makes every modification of the simulated world observable by the model-checker,
+ * allowing the whole MC business.
*
- * @ref simix::kernelSync() is a higher level wrapper for this.
+ * It is highly inspired from the syscalls in a regular operating system, allowing the user code to get some specific
+ * code executed in the kernel context. But here, there is almost no security involved. Parameters get checked for
+ * finiteness but that's all. The main goal remain to ensure reproducible ordering of uncomparable events (in
+ * [parallel] simulation) and observability of events (in model-checking).
+ *
+ * The code passed as argument is supposed to terminate at the exact same simulated timestamp.
+ * Do not use it if your code may block waiting for a subsequent event, e.g. if you lock a mutex,
+ * you may need to wait for that mutex to be unlocked by its current owner.
+ * Potentially blocking simcall must be issued using simcall_blocking(), right below in this file.
*/
-XBT_PUBLIC void simcall_run_blocking(std::function<void()> const& code);
-
-template<class F> inline
-void simcall_run_kernel(F& f)
+template <class F> typename std::result_of_t<F()> simcall(F&& code, mc::SimcallInspector* t = nullptr)
{
- simcall_run_kernel(std::function<void()>(std::ref(f)));
-}
-template<class F> inline
-void simcall_run_blocking(F& f)
-{
- simcall_run_blocking(std::function<void()>(std::ref(f)));
-}
-
-namespace simgrid {
+ // If we are in the maestro, we take the fast path and execute the
+ // code directly without simcall marshalling/unmarshalling/dispatch:
+ if (SIMIX_is_maestro())
+ return std::forward<F>(code)();
-namespace simix {
+ // If we are in the application, pass the code to the maestro which
+ // executes it for us and reports the result. We use a std::future which
+ // conveniently handles the success/failure value for us.
+ using R = typename std::result_of_t<F()>;
+ simgrid::xbt::Result<R> result;
+ simcall_run_kernel([&result, &code] { simgrid::xbt::fulfill_promise(result, std::forward<F>(code)); }, t);
+ return result.get();
+}
-/** Execute some code in the kernel/maestro
+/** Execute some code (that does not return immediately) in kernel context
+ *
+ * This is very similar to simcall() right above, but the calling actor will not get rescheduled until
+ * actor->simcall_answer() is called explicitly.
+ *
+ * Since the return value does not come from the lambda directly, its type cannot be guessed automatically and must
+ * be provided as template parameter.
+ *
+ * This is meant for blocking actions. For example, locking a mutex is a blocking simcall.
+ * First it's a simcall because that's obviously a modification of the world. Then, that's a blocking simcall because if
+ * the mutex happens not to be free, the actor is added to a queue of actors in the mutex. Every mutex->unlock() takes
+ * the first actor from the queue, mark it as current owner of the mutex and call actor->simcall_answer() to mark that
+ * this mutex is now unblocked and ready to run again. If the mutex is initially free, the calling actor is unblocked
+ * right away with actor->simcall_answer() once the mutex is marked as locked.
*
- * This can be used to enforce mutual exclusion with other simcall.
- * More importantly, this enforces a deterministic/reproducible ordering
- * of the operation with respect to other simcalls.
+ * If your code never calls actor->simcall_answer() itself, the actor will never return from its simcall.
*/
-template <class F> typename std::result_of<F()>::type simcall(F&& code)
+template <class R, class F> R simcall_blocking(F&& code, mc::SimcallInspector* t = nullptr)
{
// If we are in the maestro, we take the fast path and execute the
- // code directly without simcall mashalling/unmarshalling/dispatch:
+ // code directly without simcall marshalling/unmarshalling/dispatch:
if (SIMIX_is_maestro())
return std::forward<F>(code)();
// If we are in the application, pass the code to the maestro which
// executes it for us and reports the result. We use a std::future which
// conveniently handles the success/failure value for us.
- typedef typename std::result_of<F()>::type R;
simgrid::xbt::Result<R> result;
- simcall_run_kernel([&] { simgrid::xbt::fulfill_promise(result, std::forward<F>(code)); });
+ simcall_run_blocking([&result, &code] { simgrid::xbt::fulfill_promise(result, std::forward<F>(code)); }, t);
return result.get();
}
+} // namespace actor
+} // namespace kernel
+} // namespace simgrid
+namespace simgrid {
+namespace simix {
-XBT_PUBLIC const std::vector<smx_actor_t>& process_get_runnable();
-
-// What's executed as SIMIX actor code:
-typedef std::function<void()> ActorCode;
+inline auto& simix_timers() // avoid static initialization order fiasco
+{
+ using TimerQelt = std::pair<double, Timer*>;
+ static boost::heap::fibonacci_heap<TimerQelt, boost::heap::compare<xbt::HeapComparator<TimerQelt>>> value;
+ return value;
+}
-// Create an ActorCode based on a std::string
-typedef std::function<ActorCode(std::vector<std::string> args)> ActorCodeFactory;
+/** @brief Timer datatype */
+class Timer {
+ double date = 0.0;
-XBT_PUBLIC void register_function(std::string name, ActorCodeFactory factory);
-}
-}
+public:
+ std::remove_reference_t<decltype(simix_timers())>::handle_type handle_;
-/*
- * Type of function that creates a process.
- * The function must accept the following parameters:
- * void* process: the process created will be stored there
- * const char *name: a name for the object. It is for user-level information and can be NULL
- * xbt_main_func_t code: is a function describing the behavior of the process
- * void *data: data a pointer to any data one may want to attach to the new object.
- * sg_host_t host: the location where the new process is executed
- * int argc, char **argv: parameters passed to code
- * std::map<std::string, std::string>* props: properties
- */
-typedef smx_actor_t (*smx_creation_func_t)(
- /* name */ std::string, simgrid::simix::ActorCode code,
- /* userdata */ void*,
- /* hostname */ sg_host_t,
- /* props */ std::unordered_map<std::string, std::string>*,
- /* parent_process */ smx_actor_t);
+ Timer(double date, simgrid::xbt::Task<void()>&& callback) : date(date), callback(std::move(callback)) {}
-XBT_PUBLIC smx_actor_t simcall_process_create(std::string name, simgrid::simix::ActorCode code, void* data,
- sg_host_t host, std::unordered_map<std::string, std::string>* properties);
+ simgrid::xbt::Task<void()> callback;
+ double get_date() const { return date; }
+ void remove();
-XBT_PUBLIC smx_timer_t SIMIX_timer_set(double date, simgrid::xbt::Task<void()> callback);
+ template <class F> static inline Timer* set(double date, F callback)
+ {
+ return set(date, simgrid::xbt::Task<void()>(std::move(callback)));
+ }
-template<class F> inline
-smx_timer_t SIMIX_timer_set(double date, F callback)
-{
- return SIMIX_timer_set(date, simgrid::xbt::Task<void()>(std::move(callback)));
-}
+ static Timer* set(double date, simgrid::xbt::Task<void()>&& callback);
+ static double next() { return simix_timers().empty() ? -1.0 : simix_timers().top().first; }
+};
-template<class R, class T> inline
-smx_timer_t SIMIX_timer_set(double date, R(*callback)(T*), T* arg)
-{
- return SIMIX_timer_set(date, [=](){ callback(arg); });
-}
+} // namespace simix
+} // namespace simgrid
#endif