1 /* a fast and simple context switching library */
3 /* Copyright (c) 2004-2008 the SimGrid team. */
4 /* All rights reserved. */
6 /* This program is free software; you can redistribute it and/or modify it
7 * under the terms of the license (GNU LGPL) which comes with this package. */
14 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_context, simix, "Context switching mecanism");
16 const char *xbt_ctx_factory_to_use = NULL;
19 * This function is call by SIMIX_global_init() to initialize the context module.
21 void SIMIX_context_mod_init(void)
23 if (!simix_global->context_factory) {
24 /* select context factory to use to create the context(depends of the macro definitions) */
25 if (xbt_ctx_factory_to_use) {
26 SIMIX_context_select_factory(xbt_ctx_factory_to_use);
28 #ifdef CONTEXT_THREADS
29 /* context switch based os thread */
30 SIMIX_ctx_thread_factory_init(&simix_global->context_factory);
32 /* context switch based ucontext */
33 SIMIX_ctx_sysv_factory_init(&simix_global->context_factory);
35 /* context switch is not allowed on Windows */
36 #error ERROR [__FILE__, line __LINE__]: no context based implementation specified.
43 * This function is call by SIMIX_clean() to finalize the context module.
45 void SIMIX_context_mod_exit(void)
47 if (simix_global->context_factory) {
48 smx_pfn_context_factory_finalize_t finalize_factory;
50 /* finalize the context factory */
51 finalize_factory = simix_global->context_factory->finalize;
52 (*finalize_factory) (&simix_global->context_factory);
57 * This function is used to change the context factory.
58 * Warning: it destroy all the existing processes (even for maestro), and it
59 * will create a new maestro process using the new context factory.
61 int SIMIX_context_select_factory(const char *name)
63 /* if a context factory is already instantiated and it is different from the
64 newly selected one, then kill all the processes, exit the context module
65 and initialize the new factory.
67 if (simix_global->context_factory != NULL) {
68 if (strcmp(simix_global->context_factory->name, name)){
70 SIMIX_process_killall();
72 /* kill maestro process */
73 SIMIX_context_free(simix_global->maestro_process->context);
74 free(simix_global->maestro_process);
75 simix_global->maestro_process = NULL;
77 SIMIX_context_mod_exit();
80 /* the same context factory is requested return directly */
84 /* init the desired factory */
85 SIMIX_context_init_factory_by_name(&simix_global->context_factory, name);
87 SIMIX_create_maestro_process ();
93 * Initializes a context factory given by its name
95 void SIMIX_context_init_factory_by_name(smx_context_factory_t * factory,
98 if (!strcmp(name, "java"))
100 SIMIX_ctx_java_factory_init(factory);
102 THROW0(not_found_error, 0, "Factory 'Java' does not exist: Java support was not compiled in the SimGrid library");
103 #endif /* HAVE_JAVA */
105 else if (!strcmp(name, "thread"))
106 #ifdef CONTEXT_THREADS
107 SIMIX_ctx_thread_factory_init(factory);
109 THROW0(not_found_error, 0, "Factory 'thread' does not exist: thread support was not compiled in the SimGrid library");
110 #endif /* CONTEXT_THREADS */
112 else if (!strcmp(name, "sysv"))
113 #if !defined(WIN32) && !defined(CONTEXT_THREADS)
114 SIMIX_ctx_sysv_factory_init(factory);
116 THROW0(not_found_error, 0, "Factory 'sysv' does not exist: no System V thread support under Windows");
118 else if (!strcmp(name, "lua"))
120 SIMIX_ctx_lua_factory_init(factory);
122 THROW0(not_found_error, 0, "Factory 'lua' does not exist: Lua support was not compiled in the SimGrid library");
123 #endif /* HAVE_LUA */
125 THROW1(not_found_error, 0, "Factory '%s' does not exist", name);