X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/465dac153770a28f3a334705a06a1ee7a457c965..2d37e348a09783cda723c7019640ee69de168324:/src/kernel/context/ContextUnix.cpp

diff --git a/src/kernel/context/ContextUnix.cpp b/src/kernel/context/ContextUnix.cpp
index de67f76e93..a39ef84980 100644
--- a/src/kernel/context/ContextUnix.cpp
+++ b/src/kernel/context/ContextUnix.cpp
@@ -17,13 +17,39 @@
 
 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(simix_context);
 
-/** Many integers are needed to store a pointer
- *
- * Support up to two ints. */
+/** Up to two integers may be needed to store a pointer on the system we target */
 constexpr int CTX_ADDR_LEN = 2;
 
 static_assert(sizeof(simgrid::kernel::context::UContext*) <= CTX_ADDR_LEN * sizeof(int),
-              "Ucontexts are not supported on this arch yet");
+              "Ucontexts are not supported on this arch yet. Please increase CTX_ADDR_LEN.");
+
+/* Make sure that this symbol is easy to recognize by name, even on exotic platforms */
+extern "C" {
+static void smx_ctx_wrapper(int i1, int i2);
+}
+
+// The name of this function is currently hardcoded in MC (as string).
+// Do not change it without fixing those references as well.
+static void smx_ctx_wrapper(int i1, int i2)
+{
+  // Rebuild the Context* pointer from the integers:
+  int ctx_addr[CTX_ADDR_LEN] = {i1, i2};
+  simgrid::kernel::context::UContext* context;
+  memcpy(&context, ctx_addr, sizeof context);
+
+  ASAN_FINISH_SWITCH(nullptr, &context->asan_ctx_->asan_stack_, &context->asan_ctx_->asan_stack_size_);
+  try {
+    (*context)();
+    context->Context::stop();
+  } catch (simgrid::kernel::context::StopRequest const&) {
+    XBT_DEBUG("Caught a StopRequest");
+  } catch (simgrid::Exception const& e) {
+    XBT_INFO("Actor killed by an uncatched exception %s", simgrid::xbt::demangle(typeid(e).name()).get());
+    throw;
+  }
+  ASAN_ONLY(context->asan_stop_ = true);
+  context->suspend();
+}
 
 namespace simgrid {
 namespace kernel {
@@ -42,60 +68,26 @@ UContext::UContext(std::function<void()> code, void_pfn_smxprocess_t cleanup_fun
                    SwappedContextFactory* factory)
     : SwappedContext(std::move(code), cleanup_func, actor, factory)
 {
-  /* if the user provided a function for the process then use it, otherwise it is the context for maestro */
+  /* if the user provided a function for the actor then use it. If not, nothing to do for maestro. */
   if (has_code()) {
     getcontext(&this->uc_);
     this->uc_.uc_link = nullptr;
     this->uc_.uc_stack.ss_sp   = sg_makecontext_stack_addr(get_stack());
     this->uc_.uc_stack.ss_size = sg_makecontext_stack_size(smx_context_usable_stack_size);
-#if PTH_STACKGROWTH == -1
-    ASAN_ONLY(this->asan_stack_ = static_cast<char*>(get_stack()) + smx_context_usable_stack_size);
-#else
-    ASAN_ONLY(this->asan_stack_ = get_stack());
-#endif
-    UContext::make_ctx(&this->uc_, UContext::smx_ctx_sysv_wrapper, this);
-  }
+    // Makecontext expects integer arguments; we want to pass a pointer.
+    // This context address is decomposed into a serie of integers, which are passed as arguments to makecontext.
+
+    int ctx_addr[CTX_ADDR_LEN]{};
+    UContext* arg = this;
+    memcpy(ctx_addr, &arg, sizeof this);
+    makecontext(&this->uc_, (void (*)())smx_ctx_wrapper, 2, ctx_addr[0], ctx_addr[1]);
 
 #if SIMGRID_HAVE_MC
-  if (MC_is_active() && has_code()) {
-    MC_register_stack_area(get_stack(), actor, &(this->uc_), smx_context_usable_stack_size);
-  }
+    if (MC_is_active()) {
+      MC_register_stack_area(get_stack(), actor, &(this->uc_), smx_context_usable_stack_size);
+    }
 #endif
-}
-
-// The name of this function is currently hardcoded in the code (as string).
-// Do not change it without fixing those references as well.
-void UContext::smx_ctx_sysv_wrapper(int i1, int i2)
-{
-  // Rebuild the Context* pointer from the integers:
-  int ctx_addr[CTX_ADDR_LEN] = {i1, i2};
-  simgrid::kernel::context::UContext* context;
-  memcpy(&context, ctx_addr, sizeof context);
-
-  ASAN_FINISH_SWITCH(nullptr, &context->asan_ctx_->asan_stack_, &context->asan_ctx_->asan_stack_size_);
-  try {
-    (*context)();
-  } catch (simgrid::kernel::context::Context::StopRequest const&) {
-    XBT_DEBUG("Caught a StopRequest");
-  } catch (simgrid::Exception const& e) {
-    XBT_INFO("Actor killed by an uncatched exception %s", simgrid::xbt::demangle(typeid(e).name()).get());
-    throw;
   }
-  context->Context::stop();
-  ASAN_ONLY(context->asan_stop_ = true);
-  context->suspend();
-}
-
-/** A better makecontext
- *
- * Makecontext expects integer arguments, we the context variable is decomposed into a serie of integers and each
- * integer is passed as argument to makecontext.
- */
-void UContext::make_ctx(ucontext_t* ucp, void (*func)(int, int), UContext* arg)
-{
-  int ctx_addr[CTX_ADDR_LEN]{};
-  memcpy(ctx_addr, &arg, sizeof arg);
-  makecontext(ucp, (void (*)())func, 2, ctx_addr[0], ctx_addr[1]);
 }
 
 void UContext::swap_into(SwappedContext* to_)