1 /* context_thread - implementation of context switching with native threads */
3 /* Copyright (c) 2009, 2010. 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. */
9 #include "xbt/function_types.h"
11 #include "portable.h" /* loads context system definitions */
13 #include "xbt/xbt_os_thread.h"
14 #include "xbt_modinter.h" /* prototype of os thread module's init/exit in XBT */
15 #include "simix/context.h"
17 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(simix_context);
19 int smx_parallel_contexts = 0;
21 typedef struct s_smx_ctx_thread {
22 s_smx_ctx_base_t super; /* Fields of super implementation */
23 xbt_os_thread_t thread; /* a plain dumb thread (portable to posix or windows) */
24 xbt_os_sem_t begin; /* this semaphore is used to schedule/yield the process */
25 xbt_os_sem_t end; /* this semaphore is used to schedule/unschedule the process */
26 } s_smx_ctx_thread_t, *smx_ctx_thread_t;
29 smx_ctx_thread_factory_create_context(xbt_main_func_t code, int argc,
31 void_pfn_smxprocess_t cleanup_func,
34 static void smx_ctx_thread_free(smx_context_t context);
35 static void smx_ctx_thread_stop(smx_context_t context);
36 static void smx_ctx_thread_suspend(smx_context_t context);
37 static void smx_ctx_thread_resume(smx_context_t new_context);
38 static void smx_ctx_thread_runall_serial(xbt_dynar_t processes);
39 static void smx_ctx_thread_runall_parallel(xbt_dynar_t processes);
40 static smx_context_t smx_ctx_thread_self(void);
42 static void *smx_ctx_thread_wrapper(void *param);
44 void SIMIX_ctx_thread_factory_init(smx_context_factory_t * factory)
46 smx_ctx_base_factory_init(factory);
47 VERB0("Activating thread context factory");
49 (*factory)->create_context = smx_ctx_thread_factory_create_context;
50 /* Do not overload that method (*factory)->finalize */
51 (*factory)->free = smx_ctx_thread_free;
52 (*factory)->stop = smx_ctx_thread_stop;
53 (*factory)->suspend = smx_ctx_thread_suspend;
55 if (smx_parallel_contexts)
56 (*factory)->runall = smx_ctx_thread_runall_parallel;
58 (*factory)->runall = smx_ctx_thread_runall_serial;
60 (*factory)->self = smx_ctx_thread_self;
61 (*factory)->name = "ctx_thread_factory";
65 smx_ctx_thread_factory_create_context(xbt_main_func_t code, int argc,
67 void_pfn_smxprocess_t cleanup_func,
70 smx_ctx_thread_t context = (smx_ctx_thread_t)
71 smx_ctx_base_factory_create_context_sized(sizeof(s_smx_ctx_thread_t),
75 /* If the user provided a function for the process then use it
76 otherwise is the context for maestro */
78 context->begin = xbt_os_sem_init(0);
79 context->end = xbt_os_sem_init(0);
80 /* create and start the process */
81 /* NOTE: The first argument to xbt_os_thread_create used to be the process *
82 * name, but now the name is stored at SIMIX level, so we pass a null */
84 xbt_os_thread_create(NULL, smx_ctx_thread_wrapper, context, context);
86 /* wait the starting of the newly created process */
87 xbt_os_sem_acquire(context->end);
90 xbt_os_thread_set_extra_data(context);
93 return (smx_context_t) context;
96 static void smx_ctx_thread_free(smx_context_t pcontext)
98 smx_ctx_thread_t context = (smx_ctx_thread_t) pcontext;
100 /* check if this is the context of maestro (it doesn't has a real thread) */
101 if (context->thread) {
102 /* wait about the thread terminason */
103 xbt_os_thread_join(context->thread, NULL);
105 /* destroy the synchronisation objects */
106 xbt_os_sem_destroy(context->begin);
107 xbt_os_sem_destroy(context->end);
110 smx_ctx_base_free(pcontext);
113 static void smx_ctx_thread_stop(smx_context_t pcontext)
115 smx_ctx_thread_t context = (smx_ctx_thread_t) pcontext;
117 /* please no debug here: our procdata was already free'd */
118 smx_ctx_base_stop(pcontext);
120 /* signal to the maestro that it has finished */
121 xbt_os_sem_release(((smx_ctx_thread_t) context)->end);
124 /* We should provide return value in case other wants it */
125 xbt_os_thread_exit(NULL);
128 static void *smx_ctx_thread_wrapper(void *param)
130 smx_ctx_thread_t context = (smx_ctx_thread_t) param;
132 /* Tell the maestro we are starting, and wait for its green light */
133 xbt_os_sem_release(context->end);
134 xbt_os_sem_acquire(context->begin);
136 (context->super.code) (context->super.argc, context->super.argv);
138 smx_ctx_thread_stop((smx_context_t) context);
142 static void smx_ctx_thread_suspend(smx_context_t context)
144 xbt_os_sem_release(((smx_ctx_thread_t) context)->end);
145 xbt_os_sem_acquire(((smx_ctx_thread_t) context)->begin);
148 static void smx_ctx_thread_runall_serial(xbt_dynar_t processes)
150 smx_process_t process;
153 xbt_dynar_foreach(processes, cursor, process) {
154 xbt_os_sem_release(((smx_ctx_thread_t) process->context)->begin);
155 xbt_os_sem_acquire(((smx_ctx_thread_t) process->context)->end);
157 xbt_dynar_reset(processes);
160 static void smx_ctx_thread_runall_parallel(xbt_dynar_t processes)
163 smx_process_t process;
165 xbt_dynar_foreach(processes, index, process)
166 xbt_os_sem_release(((smx_ctx_thread_t) process->context)->begin);
168 xbt_dynar_foreach(processes, index, process) {
169 xbt_os_sem_acquire(((smx_ctx_thread_t) process->context)->end);
171 xbt_dynar_reset(processes);
174 static smx_context_t smx_ctx_thread_self(void)
176 return (smx_context_t) xbt_os_thread_get_extra_data();