X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/f9d7b35c174d52377ef297f786129e0340ae0778..7d12748cce3a184f60108fa8b12e0f78c6971b77:/include/simgrid/simix.hpp

diff --git a/include/simgrid/simix.hpp b/include/simgrid/simix.hpp
index 5fbc4d5fd8..2f19728b8d 100644
--- a/include/simgrid/simix.hpp
+++ b/include/simgrid/simix.hpp
@@ -24,18 +24,57 @@ XBT_PUBLIC(void) simcall_run_kernel(std::function<void()> const& code);
 namespace simgrid {
 namespace simix {
 
+/** Fulfill a promise by executing a given code */
+template<class R, class F>
+void fulfill_promise(std::promise<R>& promise, F&& code)
+{
+  try {
+    promise.set_value(std::forward<F>(code)());
+  }
+  catch(...) {
+    promise.set_exception(std::current_exception());
+  }
+}
+
+/** Fulfill a promise by executing a given code
+ *
+ *  This is a special version for `std::promise<void>` because the default
+ *  version does not compile in this case.
+ */
+template<class F>
+void fulfill_promise(std::promise<void>& promise, F&& code)
+{
+  try {
+    std::forward<F>(code)();
+    promise.set_value();
+  }
+  catch(...) {
+    promise.set_exception(std::current_exception());
+  }
+}
+
+/** Execute some code in the kernel/maestro
+ *
+ *  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.
+ */
 template<class F>
 typename std::result_of<F()>::type kernel(F&& code)
 {
+  // If we are in the maestro, we take the fast path and execute the
+  // code directly without simcall mashalling/unmarshalling/dispatch:
+  if (SIMIX_is_maestro())
+    return std::forward<F>(code)();
+
+  // If we are in the application, pass the code to the maestro which is
+  // 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;
   std::promise<R> promise;
   simcall_run_kernel([&]{
-    try {
-      promise.set_value(code());
-    }
-    catch(...) {
-      promise.set_exception(std::current_exception());
-    }
+    xbt_assert(SIMIX_is_maestro(), "Not in maestro");
+    fulfill_promise(promise, std::forward<F>(code));
   });
   return promise.get_future().get();
 }
@@ -43,7 +82,7 @@ typename std::result_of<F()>::type kernel(F&& code)
 class Context;
 class ContextFactory;
 
-class ContextFactory {
+XBT_PUBLIC_CLASS ContextFactory {
 private:
   std::string name_;
 public:
@@ -70,7 +109,7 @@ protected:
   }
 };
 
-class Context {
+XBT_PUBLIC_CLASS Context {
 private:
   std::function<void()> code_;
   void_pfn_smxprocess_t cleanup_func_ = nullptr;
@@ -107,4 +146,4 @@ public:
 }
 }
 
-#endif
\ No newline at end of file
+#endif