/* a fast and simple context switching library */
-/* Copyright (c) 2004-2008 the SimGrid team. */
-/* All rights reserved. */
+/* Copyright (c) 2009, 2010. 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 "xbt/swag.h"
#include "private.h"
-XBT_LOG_NEW_DEFAULT_SUBCATEGORY(smx_context, simix, "Context switching mecanism");
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_context, simix,
+ "Context switching mecanism");
+const char *xbt_ctx_factory_to_use = NULL;
+typedef void (*SIMIX_ctx_factory_initializer_t)(smx_context_factory_t *);
+SIMIX_ctx_factory_initializer_t factory_initializer_to_use = NULL;
-/**
- * This function is call by SIMIX_global_init() to initialize the context module.
+/**
+ * This function is called by SIMIX_global_init() to initialize the context module.
*/
void SIMIX_context_mod_init(void)
{
if (!simix_global->context_factory) {
- /* select context factory to use to create the context(depends of the macro definitions) */
-
-#ifdef CONTEXT_THREADS
- /* context switch based os thread */
- SIMIX_ctx_thread_factory_init(&simix_global->context_factory);
-#elif !defined(WIN32)
- /* context switch based ucontext */
- SIMIX_ctx_sysv_factory_init(&simix_global->context_factory);
+ /* select context factory to use to create the context(depends of the macro definitions) */
+ if (factory_initializer_to_use) {
+ (*factory_initializer_to_use)(&(simix_global->context_factory));
+ } else {
+#ifdef CONTEXT_THREADS /* Use os threads (either pthreads or windows ones) */
+ SIMIX_ctx_thread_factory_init(&simix_global->context_factory);
+#elif defined(CONTEXT_UCONTEXT) /* use ucontext */
+ SIMIX_ctx_sysv_factory_init(&simix_global->context_factory);
#else
- /* context switch is not allowed on Windows */
-#error ERROR [__FILE__, line __LINE__]: no context based implementation specified.
+#error ERROR [__FILE__, line __LINE__]: no context implementation specified.
#endif
+ }
}
}
if (simix_global->context_factory) {
smx_pfn_context_factory_finalize_t finalize_factory;
- /* if there are living processes then kill them (except maestro) */
- if(simix_global->process_list != NULL)
- SIMIX_process_killall();
-
/* finalize the context factory */
finalize_factory = simix_global->context_factory->finalize;
(*finalize_factory) (&simix_global->context_factory);
/**
* This function is used to change the context factory.
- * Warning: it destroy all the existing contexts
+ * Warning: it destroy all the existing processes (even for maestro), and it
+ * will create a new maestro process using the new context factory.
*/
int SIMIX_context_select_factory(const char *name)
{
- /* if a factory is already instantiated (SIMIX_context_mod_init() was called) */
- if (simix_global->context_factory != NULL) {
- /* if the desired factory is different of the current factory, call SIMIX_context_mod_exit() */
- if (strcmp(simix_global->context_factory->name, name))
- SIMIX_context_mod_exit();
- else
- /* the same context factory is requested return directly */
- return 0;
- }
-
- /* get the desired factory */
- SIMIX_context_init_factory_by_name(&simix_global->context_factory, name);
+ /* if a context factory is already instantiated and it is different from the
+ newly selected one, then kill all the processes, exit the context module
+ and initialize the new factory.
+ */
- /* maestro process specialisation */
- (*(simix_global->context_factory->create_maestro_context)) (&simix_global->maestro_process);
- /* the current process is the process of the maestro */
- simix_global->current_process = simix_global->maestro_process;
+ if (simix_global->context_factory != NULL) {
+ if (strcmp(simix_global->context_factory->name, name)) {
- /* the current context doesn't want to die */
- simix_global->current_process->iwannadie = 0;
+ SIMIX_process_killall();
- /* insert the current context in the list of the contexts in use */
- xbt_swag_insert(simix_global->current_process, simix_global->process_list);
+ /* kill maestro process */
+ SIMIX_context_free(simix_global->maestro_process->context);
+ free(simix_global->maestro_process);
+ simix_global->maestro_process = NULL;
- return 0;
-}
+ SIMIX_context_mod_exit();
+ } else
+ /* the same context factory is requested return directly */
+ return 0;
+ }
-/**
- * Initializes a context factory given by its name
- */
-void SIMIX_context_init_factory_by_name(smx_context_factory_t * factory,
- const char *name)
-{
+ /* init the desired factory */
+ smx_context_factory_t * factory = &simix_global->context_factory;
if (!strcmp(name, "java"))
-#ifdef HAVE_JAVA
+#ifdef HAVE_JAVA
SIMIX_ctx_java_factory_init(factory);
#else
- THROW0(not_found_error, 0, "Factory 'Java' does not exist: Java support was not compiled in the SimGrid library");
-#endif /* HAVE_JAVA */
-
+ THROW0(not_found_error, 0,
+ "Factory 'Java' does not exist: Java support was not compiled in the SimGrid library");
+#endif /* HAVE_JAVA */
+
else if (!strcmp(name, "thread"))
#ifdef CONTEXT_THREADS
SIMIX_ctx_thread_factory_init(factory);
#else
- THROW0(not_found_error, 0, "Factory 'thread' does not exist: thread support was not compiled in the SimGrid library");
-#endif /* CONTEXT_THREADS */
-
+ THROW0(not_found_error, 0,
+ "Factory 'thread' does not exist: thread support was not compiled in the SimGrid library");
+#endif /* CONTEXT_THREADS */
+
else if (!strcmp(name, "sysv"))
-#if !defined(WIN32) && !defined(CONTEXT_THREADS)
+#if !defined(_XBT_WIN32) && !defined(CONTEXT_THREADS)
SIMIX_ctx_sysv_factory_init(factory);
#else
- THROW0(not_found_error, 0, "Factory 'sysv' does not exist: no System V thread support under Windows");
-#endif
+ THROW0(not_found_error, 0,
+ "Factory 'sysv' does not exist: no System V thread support under Windows");
+#endif
+
else
THROW1(not_found_error, 0, "Factory '%s' does not exist", name);
+
+
+
+
+ SIMIX_create_maestro_process();
+
+ return 0;
}
+
