/* 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 "src/portable.h"
+#include <utility>
+#include <string>
+
+#include <xbt/config.hpp>
+#include <xbt/range.hpp>
+
+#include "src/internal_config.h"
#include "xbt/log.h"
#include "xbt/swag.h"
#include "xbt/xbt_os_thread.h"
#include "smx_private.h"
-#include "smx_private.hpp"
#include "simgrid/sg_config.h"
#include "src/internal_config.h"
#include "simgrid/modelchecker.h"
#define _aligned_free __mingw_aligned_free
#endif //MINGW
-#ifdef HAVE_VALGRIND_H
+#if HAVE_VALGRIND_H
# include <valgrind/valgrind.h>
#endif
XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_context, simix, "Context switching mechanism");
-char* smx_context_factory_name = NULL; /* factory name specified by --cfg=contexts/factory:value */
+static std::pair<const char*, simgrid::simix::ContextFactoryInitializer> context_factories[] = {
+#if HAVE_RAW_CONTEXTS
+ { "raw", simgrid::simix::raw_factory },
+#endif
+#if HAVE_UCONTEXT_CONTEXTS
+ { "ucontext", simgrid::simix::sysv_factory },
+#endif
+#if HAVE_BOOST_CONTEXTS
+ { "boost", simgrid::simix::boost_factory },
+#endif
+#if HAVE_THREAD_CONTEXTS
+ { "thread", simgrid::simix::thread_factory },
+#endif
+};
+
+static_assert(sizeof(context_factories) != 0,
+ "No context factories are enabled for this build");
+
+// Create the list of possible contexts:
+static inline
+std::string contexts_list()
+{
+ std::string res;
+ const std::size_t n = sizeof(context_factories) / sizeof(context_factories[0]);
+ for (std::size_t i = 1; i != n; ++i) {
+ res += ", ";
+ res += context_factories[i].first;
+ }
+ return res;
+}
+
+static simgrid::config::Flag<std::string> context_factory_name(
+ "contexts/factory",
+ (std::string("Possible values: ")+contexts_list()).c_str(),
+ context_factories[0].first);
+
int smx_context_stack_size;
int smx_context_stack_size_was_set = 0;
int smx_context_guard_size;
int smx_context_guard_size_was_set = 0;
-static thread_local smx_context_t smx_current_context_parallel;
+#if HAVE_THREAD_LOCAL_STORAGE
+static XBT_THREAD_LOCAL smx_context_t smx_current_context_parallel;
+#else
+static xbt_os_thread_key_t smx_current_context_key = 0;
+#endif
static smx_context_t smx_current_context_serial;
static int smx_parallel_contexts = 1;
static int smx_parallel_threshold = 2;
static e_xbt_parmap_mode_t smx_parallel_synchronization_mode = XBT_PARMAP_DEFAULT;
-/**
- * This function is called by SIMIX_global_init() to initialize the context module.
- */
-void SIMIX_context_mod_init(void)
+static inline
+void invalid_context_factory()
{
- if (!simix_global->context_factory) {
- /* select the context factory to use to create the contexts */
- if (simgrid::simix::factory_initializer)
- simix_global->context_factory = simgrid::simix::factory_initializer();
- else { /* use the factory specified by --cfg=contexts/factory:value */
-#if defined(HAVE_THREAD_CONTEXTS)
- if (!strcmp(smx_context_factory_name, "thread"))
- simix_global->context_factory = simgrid::simix::thread_factory();
+ XBT_ERROR("Invalid context factory specified. Valid factories on this machine:");
+#if HAVE_RAW_CONTEXTS
+ XBT_ERROR(" raw: high performance context factory implemented specifically for SimGrid");
#else
- if (0);
-#endif
-#ifdef HAVE_UCONTEXT_CONTEXTS
- else if (!strcmp(smx_context_factory_name, "ucontext"))
- simix_global->context_factory = simgrid::simix::sysv_factory();
-#endif
-#ifdef HAVE_RAW_CONTEXTS
- else if (!strcmp(smx_context_factory_name, "raw"))
- simix_global->context_factory = simgrid::simix::raw_factory();
-#endif
-#ifdef HAVE_BOOST_CONTEXTS
- else if (!strcmp(smx_context_factory_name, "boost"))
- simix_global->context_factory = simgrid::simix::boost_factory();
+ XBT_ERROR(" (raw contexts were disabled at compilation time on this machine -- check configure logs for details)");
#endif
- else {
- XBT_ERROR("Invalid context factory specified. Valid factories on this machine:");
-#ifdef HAVE_RAW_CONTEXTS
- XBT_ERROR(" raw: high performance context factory implemented specifically for SimGrid");
+#if HAVE_UCONTEXT_CONTEXTS
+ XBT_ERROR(" ucontext: classical system V contexts (implemented with makecontext, swapcontext and friends)");
#else
- XBT_ERROR(" (raw contexts were disabled at compilation time on this machine -- check configure logs for details)");
+ XBT_ERROR(" (ucontext was disabled at compilation time on this machine -- check configure logs for details)");
#endif
-#ifdef HAVE_UCONTEXT_CONTEXTS
- XBT_ERROR(" ucontext: classical system V contexts (implemented with makecontext, swapcontext and friends)");
+#if HAVE_BOOST_CONTEXTS
+ XBT_ERROR(" boost: this uses the boost libraries context implementation");
#else
- XBT_ERROR(" (ucontext was disabled at compilation time on this machine -- check configure logs for details)");
+ XBT_ERROR(" (boost was disabled at compilation time on this machine -- check configure logs for details. Did you install the libboost-context-dev package?)");
#endif
-#ifdef HAVE_BOOST_CONTEXTS
- XBT_ERROR(" boost: this uses the boost libraries context implementation");
-#else
- XBT_ERROR(" (boost was disabled at compilation time on this machine -- check configure logs for details. Did you install the libboost-context-dev package?)");
+ XBT_ERROR(" thread: slow portability layer using pthreads as provided by gcc");
+ xbt_die("Please use a valid factory.");
+}
+
+/**
+ * This function is called by SIMIX_global_init() to initialize the context module.
+ */
+void SIMIX_context_mod_init(void)
+{
+#if HAVE_THREAD_CONTEXTS && !HAVE_THREAD_LOCAL_STORAGE
+ /* the __thread storage class is not available on this platform:
+ * use getspecific/setspecific instead to store the current context in each thread */
+ xbt_os_thread_key_create(&smx_current_context_key);
#endif
- XBT_ERROR(" thread: slow portability layer using pthreads as provided by gcc");
- xbt_die("Please use a valid factory.");
- }
- }
+ if (simix_global->context_factory)
+ return;
+ /* select the context factory to use to create the contexts */
+ if (simgrid::simix::factory_initializer) { // Give Java a chance to hijack the factory mechanism
+ simix_global->context_factory = simgrid::simix::factory_initializer();
+ return;
}
+ /* use the factory specified by --cfg=contexts/factory:value */
+ for (auto const& factory : context_factories)
+ if (context_factory_name == factory.first) {
+ simix_global->context_factory = factory.second();
+ break;
+ }
+ if (simix_global->context_factory == nullptr)
+ invalid_context_factory();
}
/**
stack = xbt_malloc0(smx_context_stack_size);
}
-#ifdef HAVE_VALGRIND_H
+#if HAVE_VALGRIND_H
unsigned int valgrind_stack_id = VALGRIND_STACK_REGISTER(stack, (char *)stack + smx_context_stack_size);
memcpy((char *)stack + smx_context_usable_stack_size, &valgrind_stack_id, sizeof valgrind_stack_id);
#endif
if (!stack)
return;
-#ifdef HAVE_VALGRIND_H
+#if HAVE_VALGRIND_H
unsigned int valgrind_stack_id;
memcpy(&valgrind_stack_id, (char *)stack + smx_context_usable_stack_size, sizeof valgrind_stack_id);
VALGRIND_STACK_DEREGISTER(valgrind_stack_id);
}
/**
- * \brief Returns the number of parallel threads used
- * for the user contexts.
+ * @brief Returns the number of parallel threads used for the user contexts.
* \return the number of threads (1 means no parallelism)
*/
int SIMIX_context_get_nthreads(void) {
nb_threads = xbt_os_get_numcores();
XBT_INFO("Auto-setting contexts/nthreads to %d",nb_threads);
}
-#ifndef HAVE_THREAD_CONTEXTS
+#if !HAVE_THREAD_CONTEXTS
xbt_assert(nb_threads == 1, "Parallel runs are impossible when the pthreads are missing.");
#endif
smx_parallel_contexts = nb_threads;
*/
smx_context_t SIMIX_context_get_current(void)
{
- if (SIMIX_context_is_parallel())
+ if (SIMIX_context_is_parallel()) {
+#if HAVE_THREAD_LOCAL_STORAGE
return smx_current_context_parallel;
- else
+#else
+ return xbt_os_thread_get_specific(smx_current_context_key);
+#endif
+ }
+ else {
return smx_current_context_serial;
+ }
}
/**
*/
void SIMIX_context_set_current(smx_context_t context)
{
- if (SIMIX_context_is_parallel())
+ if (SIMIX_context_is_parallel()) {
+#if HAVE_THREAD_LOCAL_STORAGE
smx_current_context_parallel = context;
- else
+#else
+ xbt_os_thread_set_specific(smx_current_context_key, context);
+#endif
+ }
+ else {
smx_current_context_serial = context;
+ }
}
