Make sthread_inside_simgrid static into libsthread in the (vain) hope that it'll...

[simgrid.git] / src / kernel / context / Context.cpp

diff --git a/src/kernel/context/Context.cpp b/src/kernel/context/Context.cpp
index 145e1e1..6827ff9 100644 (file)
--- a/src/kernel/context/Context.cpp
+++ b/src/kernel/context/Context.cpp
@@ -1,35 +1,105 @@
-/* Copyright (c) 2007-2019. The SimGrid Team. All rights reserved.          */
+/* Copyright (c) 2007-2022. 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. */
 
 #include "mc/mc.h"
 
+#include "simgrid/Exception.hpp"
 #include "simgrid/s4u/Host.hpp"
 #include "src/kernel/activity/CommImpl.hpp"
 #include "src/kernel/context/Context.hpp"
-#include "src/simix/smx_private.hpp"
+#include "src/sthread/sthread.h"
 #include "src/surf/surf_interface.hpp"
 
-XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(simix_context);
+#include <vector>
 
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(ker_context, kernel, "Context switching mechanism");
 
-namespace simgrid {
-namespace kernel {
-namespace context {
+namespace simgrid::kernel::context {
 
-ContextFactoryInitializer factory_initializer = nullptr;
+std::function<ContextFactory*(void)> ContextFactory::initializer;
+
+static e_xbt_parmap_mode_t parallel_synchronization_mode = XBT_PARMAP_DEFAULT;
+static int parallel_contexts                             = 1;
+unsigned stack_size;
+unsigned guard_size;
+
+/** @brief Returns whether some parallel threads are used for the user contexts. */
+bool is_parallel()
+{
+  return parallel_contexts > 1;
+}
+
+/**
+ * @brief Returns the number of parallel threads used for the user contexts.
+ * @return the number of threads (1 means no parallelism)
+ */
+int get_nthreads()
+{
+  return parallel_contexts;
+}
+
+/**
+ * @brief Sets the number of parallel threads to use  for the user contexts.
+ *
+ * This function should be called before initializing SIMIX.
+ * A value of 1 means no parallelism (1 thread only).
+ * If the value is greater than 1, the thread support must be enabled.
+ *
+ * @param nb_threads the number of threads to use
+ */
+void set_nthreads(int nb_threads)
+{
+  if (nb_threads <= 0) {
+    nb_threads = std::thread::hardware_concurrency();
+    XBT_INFO("Auto-setting contexts/nthreads to %d", nb_threads);
+  }
+  parallel_contexts = nb_threads;
+}
+
+/**
+ * @brief Sets the synchronization mode to use when actors are run in parallel.
+ * @param mode how to synchronize threads if actors are run in parallel
+ */
+void set_parallel_mode(e_xbt_parmap_mode_t mode)
+{
+  parallel_synchronization_mode = mode;
+}
+
+/**
+ * @brief Returns the synchronization mode used when actors are run in parallel.
+ * @return how threads are synchronized if actors are run in parallel
+ */
+e_xbt_parmap_mode_t get_parallel_mode()
+{
+  return parallel_synchronization_mode;
+}
 
 ContextFactory::~ContextFactory() = default;
 
-static thread_local Context* smx_current_context = nullptr;
+thread_local Context* Context::current_context_ = nullptr;
+
+#ifndef WIN32
+/* Install or disable alternate signal stack, for SIGSEGV handler. */
+int Context::install_sigsegv_stack(stack_t* old_stack, bool enable)
+{
+  static std::vector<unsigned char> sigsegv_stack(SIGSTKSZ);
+  stack_t stack;
+  stack.ss_sp    = sigsegv_stack.data();
+  stack.ss_size  = sigsegv_stack.size();
+  stack.ss_flags = enable ? 0 : SS_DISABLE;
+  return sigaltstack(&stack, old_stack);
+}
+#endif
+
 Context* Context::self()
 {
-  return smx_current_context;
+  return current_context_;
 }
 void Context::set_current(Context* self)
 {
-  smx_current_context = self;
+  current_context_ = self;
 }
 
 void Context::declare_context(std::size_t size)
@@ -53,11 +123,11 @@ Context* ContextFactory::create_maestro(std::function<void()>&&, actor::ActorImp
     "Try using --cfg=contexts/factory:thread instead.\n");
 }
 
-Context::Context(std::function<void()>&& code, actor::ActorImpl* actor) : code_(std::move(code)), actor_(actor)
+Context::Context(std::function<void()>&& code, actor::ActorImpl* actor, bool maestro)
+    : code_(std::move(code)), actor_(actor), is_maestro_(maestro)
 {
-  /* If no function was provided, this is the context for maestro
-   * and we should set it as the current context */
-  if (not has_code())
+  /* If we are creating maestro, we should set it as the current context */
+  if (maestro)
     set_current(this);
 }
 
@@ -69,17 +139,10 @@ Context::~Context()
 
 void Context::stop()
 {
-  this->actor_->cleanup();
+  this->actor_->cleanup_from_self();
+  sthread_disable();
+  throw ForcefulKillException(); // clean RAII variables with the dedicated exception
 }
-
 AttachContext::~AttachContext() = default;
 
-} // namespace context
-} // namespace kernel
-} // namespace simgrid
-
-/** @brief Executes all the processes to run (in parallel if possible). */
-void SIMIX_context_runall()
-{
-  simix_global->context_factory->run_all();
-}
+} // namespace simgrid::kernel::context