X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/f7f21dcaaa2d53d3cd4b709b95cda97330aeca0b..6d31ded41b278226dc70b269dc7af66588e6474e:/src/xbt/context.c

diff --git a/src/xbt/context.c b/src/xbt/context.c
index b6124ce9bb..7f1159f17b 100644
--- a/src/xbt/context.c
+++ b/src/xbt/context.c
@@ -2,249 +2,478 @@
 
 /* a fast and simple context switching library                              */
 
-/* Copyright (c) 2004 Arnaud Legrand. All rights reserved.                  */
+/* Copyright (c) 2004 Arnaud Legrand.                                       */
+/* Copyright (c) 2004, 2005 Martin Quinson.                                 */
+/* 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 "portable.h"
 #include "context_private.h"
-#include "xbt/error.h"
+#include "xbt/log.h"
 #include "xbt/dynar.h"
-#include "gras_config.h"
-XBT_LOG_NEW_DEFAULT_SUBCATEGORY(context, xbt, "Context");
+#include "xbt/xbt_os_thread.h"
+#include "xbt/ex_interface.h"
 
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_ctx, xbt, "Context");
 
-/************************ GNU LIBC CONTEXTS **************************/
-#if USE_CONTEXT==1
+#define VOIRP(expr) DEBUG1("  {" #expr " = %p }", expr)
 
-static context_t current_context = NULL;
-static xbt_dynar_t context_to_destroy = NULL;
+static xbt_context_t current_context = NULL;
+static xbt_context_t init_context = NULL;
+static xbt_swag_t context_to_destroy = NULL;
+static xbt_swag_t context_living = NULL;
+#ifdef CONTEXT_THREADS
+static xbt_os_mutex_t creation_mutex;
+static xbt_os_cond_t creation_cond;
+#endif
 
-void context_init(void)
+static void __context_exit(xbt_context_t context, int value);
+static void __xbt_context_yield(xbt_context_t context)
 {
-  if(!current_context) {
-    current_context = xbt_new0(s_context_t,1);
-    context_to_destroy = xbt_dynar_new(sizeof(context_t),xbt_free);
-  }
-}
-
-void context_empty_trash(void)
-{
-  xbt_dynar_reset(context_to_destroy);
-}
-
-static void *__context_wrapper(void *c)
-{
-  context_t context = c;
-  int i;
-
-/*   msg_global->current_process = process; */
-
-  /*  WARNING("Calling the main function"); */
-  (context->code) (context->argc,context->argv);
+  xbt_assert0(current_context, "You have to call context_init() first.");
 
-  for(i=0;i<context->argc; i++) 
-    if(context->argv[i]) xbt_free(context->argv[i]);
-  if(context->argv) xbt_free(context->argv);
+  DEBUG2
+      ("--------- current_context (%p) is yielding to context(%p) ---------",
+       current_context, context);
 
-  xbt_dynar_push(context_to_destroy, &context);
+#ifdef CONTEXT_THREADS
+  if (context) {
+    xbt_context_t self = current_context;
+    DEBUG2("[%p] **** Locking ctx %p ****", self, context);
+    xbt_os_mutex_lock(context->mutex);
+    DEBUG1("[%p] **** Updating current_context ****", self);
+    current_context = context;
+    DEBUG1("[%p] **** Releasing the prisonner ****", self);
+    xbt_os_cond_signal(context->cond);
+    DEBUG3("[%p] **** Going to jail on individual %p/%p ****", self,
+	   context->cond, context->mutex);
+    xbt_os_cond_wait(context->cond, context->mutex);
+    DEBUG2("[%p] **** Unlocking individual %p ****", self, context->mutex);
+    xbt_os_mutex_unlock(context->mutex);
+    DEBUG1("[%p] **** Updating current_context ****", self);
+    current_context = self;
+  }
+#else				/* use SUSv2 contexts */
+  VOIRP(current_context);
+  if (current_context)
+    VOIRP(current_context->save);
 
-  context_yield(context);
+  VOIRP(context);
 
-  return NULL;
-}
+  if (context)
+    VOIRP(context->save);
 
-void context_start(context_t context) 
-{
+  if (context) {
 
-/*   TBX_FIFO_insert(msg_global->process, process); */
-/*   TBX_FIFO_insert(msg_global->process_to_run, process); */
+    int return_value = 0;
+
+    if (context->save == NULL) {
+
+      DEBUG1("[%p] **** Yielding to somebody else ****", current_context);
+      DEBUG2("Saving current_context value (%p) to context(%p)->save",
+	     current_context, context);
+      context->save = current_context;
+      DEBUG1("current_context becomes  context(%p) ", context);
+      current_context = context;
+      DEBUG1
+	  ("Current position memorized (context->save). Jumping to context (%p)",
+	   context);
+      return_value = swapcontext(&(context->save->uc), &(context->uc));
+      xbt_assert0((return_value == 0), "Context swapping failure");
+      DEBUG1("I am (%p). Coming back\n", context);
+    } else {
+      xbt_context_t old_context = context->save;
+      DEBUG1("[%p] **** Back ! ****", context);
+      DEBUG2("Setting current_context (%p) to context(%p)->save",
+	     current_context, context);
+      current_context = context->save;
+      DEBUG1("Setting context(%p)->save to NULL", context);
+      context->save = NULL;
+      DEBUG2("Current position memorized (%p). Jumping to context (%p)",
+	     context, old_context);
+      return_value = swapcontext(&(context->uc), &(old_context->uc));
+      xbt_assert0((return_value == 0), "Context swapping failure");
+      DEBUG1("I am (%p). Coming back\n", context);
 
-  /*  WARNING("Assigning __MSG_process_launcher to context (%p)",context); */
-  makecontext (&(context->uc), (void (*) (void)) __context_wrapper,
-	       1, context);
+    }
+  }
+#endif
+  if (current_context->iwannadie)
+    __context_exit(current_context, 1);
 
   return;
 }
 
-context_t context_create(context_function_t code,
-			 int argc, char *argv[])
+static void xbt_context_free(xbt_context_t context)
 {
-  context_t res = NULL;
+  if (!context)
+    return;
+  DEBUG1("Freeing %p", context);
+#ifdef CONTEXT_THREADS
+  /*DEBUG1("\t joining %p",(void *)context->thread->t); */
+  DEBUG1("\t joining %p", (void *) context->thread);
 
-  res = xbt_new0(s_context_t,1);
+  xbt_os_thread_join(context->thread, NULL);
 
-  /*  WARNING("Initializing context (%p)",res); */
+  DEBUG1("\t mutex_destroy %p", (void *) context->mutex);
+  xbt_os_mutex_destroy(context->mutex);
+  DEBUG1("\t cond_destroy %p", (void *) context->cond);
+  xbt_os_cond_destroy(context->cond);
 
-  xbt_assert0(getcontext(&(res->uc))==0,"Error in context saving.");
+  context->thread = NULL;
+  context->mutex = NULL;
+  context->cond = NULL;
+#endif
 
-  /*  VOIRP(res->uc); */
-  res->code = code;
-  res->uc.uc_link = &(current_context->uc); /* FIXME LATER */
-  /* WARNING : when this context is over, the current_context (i.e. the 
-     father), is awaken... May result in bugs later.*/
-  res->uc.uc_stack.ss_sp = res->stack;
-  res->uc.uc_stack.ss_size = STACK_SIZE;
-  return res;
-}
-
-static void context_destroy(context_t context)
-{
-  xbt_free(context);
+  if (context->exception)
+    free(context->exception);
 
+  free(context);
   return;
 }
 
-void context_yield(context_t context)
+static void __context_exit(xbt_context_t context, int value)
 {
+  int i;
 
-  xbt_assert0(current_context,"You have to call context_init() first.");
-
-  /*   __MSG_context_init(); */
-  /*  fprintf(stderr,"\n"); */
-  /*  WARNING("--------- current_context (%p) is yielding to context(%p) ---------",current_context,context); */
-  /*  VOIRP(current_context); */
-  /*  if(current_context) VOIRP(current_context->save); */
-  /*  VOIRP(context); */
-  /*  if(context) VOIRP(context->save); */
+  DEBUG1("--------- %p is exiting ---------", context);
 
-  if (context) {
-/*     m_process_t self = msg_global->current_process; */
-    if(context->save==NULL) {
-      /*      WARNING("**** Yielding to somebody else ****"); */
-      /*      WARNING("Saving current_context value (%p) to context(%p)->save",current_context,context); */
-      context->save = current_context ;
-      context->uc.uc_link = &(current_context->uc);
-      /*      WARNING("current_context becomes  context(%p) ",context); */
-      current_context = context ;
-      /*      WARNING("Current position memorized (context->save). Jumping to context (%p)",context); */
-      if(!swapcontext (&(context->save->uc), &(context->uc))) 
-	xbt_assert0(0,"Context swapping failure");
-      /*      WARNING("I am (%p). Coming back\n",context); */
-    } else {
-      context_t old_context = context->save ;
-      /*      WARNING("**** Back ! ****"); */
-      /*      WARNING("Setting current_context (%p) to context(%p)->save",current_context,context); */
-      current_context = context->save ;
-      /*      WARNING("Setting context(%p)->save to NULL",current_context,context); */
-      context->save = NULL ;
-      /*      WARNING("Current position memorized (%p). Jumping to context (%p)",context,old_context); */
-      if(!swapcontext (&(context->uc), &(old_context->uc)) ) 
-	xbt_assert0(0,"Context swapping failure");
-      /*      WARNING("I am (%p). Coming back\n",context); */
-    }
-/*     msg_global->current_process = self; */
+  DEBUG0("Calling cleanup functions");
+  if (context->cleanup_func) {
+    DEBUG0("Calling cleanup function");
+    context->cleanup_func(context->cleanup_arg);
   }
 
-  return;
+  DEBUG0("Freeing arguments");
+  for (i = 0; i < context->argc; i++)
+    if (context->argv[i])
+      free(context->argv[i]);
+
+  if (context->argv)
+    free(context->argv);
+
+  DEBUG0("Putting context in the to_destroy set");
+  xbt_swag_remove(context, context_living);
+  xbt_swag_insert(context, context_to_destroy);
+  DEBUG0("Context put in the to_destroy set");
+
+  DEBUG0("Yielding");
+
+#ifdef CONTEXT_THREADS
+  DEBUG2("[%p] **** Locking %p ****", context, context->mutex);
+  xbt_os_mutex_lock(context->mutex);
+/* 	DEBUG1("[%p] **** Updating current_context ****"); */
+/* 	current_context = context; */
+  DEBUG1("[%p] **** Releasing the prisonner ****", context);
+  xbt_os_cond_signal(context->cond);
+  DEBUG2("[%p] **** Unlocking individual %p ****", context,
+	 context->mutex);
+  xbt_os_mutex_unlock(context->mutex);
+  DEBUG1("[%p] **** Exiting ****", context);
+  xbt_os_thread_exit(NULL);	// We should provide return value in case other wants it
+#else
+  __xbt_context_yield(context);
+#endif
+  xbt_assert0(0, "You can't be here!");
 }
-#else 
-
-/****************************** PTHREADS ***************************/
-/* #if HAVE_LIBPTHREAD==1 */
-#ifdef HAVE_LIBPTHREAD  /* Nevermind, let's use pthreads... */
 
-static void *__MSG_process_launcher(void *p)
+static void *__context_wrapper(void *c)
 {
-  m_process_t process = (m_process_t) p;
-  sim_data_process_t sim_data = process->simdata;
-  context_t context = NULL;
-  int i;
-  msg_global->current_process = process;
-  TBX_FIFO_insert(msg_global->process, process);
+  xbt_context_t context = current_context;
+
+#ifdef CONTEXT_THREADS
+  context = (xbt_context_t) c;
+  context->thread = xbt_os_thread_self();
 
-  TBX_FIFO_insert(msg_global->process_to_run, process);
-/*   pthread_mutex_lock(&(sim_data->context->mutex)); */
-  __MSG_context_yield(sim_data->context);
+  DEBUG3("**[ctx:%p;self:%p]** Lock creation_mutex %p ****", context,
+	 (void *) xbt_os_thread_self(), creation_mutex);
+  xbt_os_mutex_lock(creation_mutex);
+  xbt_os_mutex_lock(context->mutex);
 
-  (*sim_data->context->code) (sim_data->argc,sim_data->argv);
+  DEBUG4
+      ("**[ctx:%p;self:%p]** Releasing the creator (creation_cond %p,%p) ****",
+       context, (void *) xbt_os_thread_self(), creation_cond,
+       creation_mutex);
+  xbt_os_cond_signal(creation_cond);
+  xbt_os_mutex_unlock(creation_mutex);
 
-  TBX_FIFO_remove(msg_global->process, process);
-  TBX_FIFO_remove(msg_global->process_to_run, process);
+  DEBUG4("**[ctx:%p;self:%p]** Going to Jail on lock %p and cond %p ****",
+	 context, (void *) xbt_os_thread_self(), context->mutex,
+	 context->cond);
+  xbt_os_cond_wait(context->cond, context->mutex);
 
-  /* Free blocked process if any */
-/*   pthread_mutex_lock(&(sim_data->context->mutex)); */
-/*   pthread_cond_signal(&(sim_data->context->cond)); */
-/*   pthread_mutex_unlock(&(sim_data->context->mutex)); */
+  DEBUG3("**[ctx:%p;self:%p]** Unlocking individual %p ****",
+	 context, (void *) xbt_os_thread_self(), context->mutex);
+  xbt_os_mutex_unlock(context->mutex);
 
-  context = sim_data->context;
+#endif
 
-  for(i=0;i<sim_data->argc; i++) 
-    if(sim_data->argv[i]) FREE(sim_data->argv[i]);
-  if(sim_data->argv) FREE(sim_data->argv);
-  if(process->name) FREE(process->name);
-  FREE(sim_data);
-  FREE(process);
+  if (context->startup_func)
+    context->startup_func(context->startup_arg);
 
-  TBX_FIFO_insert(msg_global->context_to_destroy,context);
-  __MSG_context_yield(context);
-/*   __MSG_context_destroy(&context); */
+  DEBUG0("Calling the main function");
 
+  __context_exit(context, (context->code) (context->argc, context->argv));
   return NULL;
 }
 
-MSG_error_t __MSG_context_start(m_process_t process) 
+/* callback: context fetching */
+static ex_ctx_t *__context_ex_ctx(void)
 {
-  sim_data_process_t sim_data = NULL;
-
-  sim_data = process->simdata;
+  return current_context->exception;
+}
 
-  pthread_mutex_lock(&(sim_data->context->mutex));
+/* callback: termination */
+static void __context_ex_terminate(xbt_ex_t * e)
+{
+  xbt_ex_display(e);
+
+  abort();
+  /* FIXME: there should be a configuration variable to choose this
+     if(current_context!=init_context) 
+     __context_exit(current_context, e->value);
+     else
+     abort();
+   */
+}
 
-  /* Launch the thread */
-  if (pthread_create(sim_data->context->thread, NULL, __MSG_process_launcher,
-		     process) != 0) {
-    WARNING("Unable to create a thread.");
-    return MSG_FATAL;
+/** \name Functions 
+ *  \ingroup XBT_context
+ */
+/* @{ */
+/** Context module initialization
+ *
+ * \warning It has to be called before using any other function of this module.
+ */
+void xbt_context_init(void)
+{
+  if (!current_context) {
+    current_context = init_context = xbt_new0(s_xbt_context_t, 1);
+    DEBUG1("Init Context (%p)", init_context);
+
+    init_context->iwannadie = 0; /* useless but makes valgrind happy */
+    init_context->exception = xbt_new(ex_ctx_t, 1);
+    XBT_CTX_INITIALIZE(init_context->exception);
+    __xbt_ex_ctx = __context_ex_ctx;
+    __xbt_ex_terminate = __context_ex_terminate;
+    context_to_destroy =
+	xbt_swag_new(xbt_swag_offset(*current_context, hookup));
+    context_living =
+	xbt_swag_new(xbt_swag_offset(*current_context, hookup));
+    xbt_swag_insert(init_context, context_living);
+#ifdef CONTEXT_THREADS
+    creation_mutex = xbt_os_mutex_init();
+    creation_cond = xbt_os_cond_init();
+#endif
   }
-  pthread_cond_wait(&(sim_data->context->cond), &(sim_data->context->mutex));
-  pthread_mutex_unlock(&(sim_data->context->mutex));
-/*   __MSG_context_yield(sim_data->context); */
+}
 
-  return MSG_OK;
+/** Garbage collection
+ *
+ * Should be called some time to time to free the memory allocated for contexts
+ * that have finished executing their main functions.
+ */
+void xbt_context_empty_trash(void)
+{
+  xbt_context_t context = NULL;
+  DEBUG1("Emptying trashbin (%d contexts to free)",
+	 xbt_swag_size(context_to_destroy));
+  while ((context = xbt_swag_extract(context_to_destroy)))
+    xbt_context_free(context);
+}
+
+/** 
+ * \param context the context to start
+ * 
+ * Calling this function prepares \a context to be run. It will 
+   however run effectively only when calling #xbt_context_schedule
+ */
+void xbt_context_start(xbt_context_t context)
+{
+#ifdef CONTEXT_THREADS
+  /* Launch the thread */
+  DEBUG3("**[ctx:%p;self:%p]** Locking creation_mutex %p ****", context,
+	 xbt_os_thread_self(), creation_mutex);
+  xbt_os_mutex_lock(creation_mutex);
+
+  DEBUG2("**[ctx:%p;self:%p]** Thread create ****", context,
+	 xbt_os_thread_self());
+  context->thread = xbt_os_thread_create(__context_wrapper, context);
+  DEBUG3("**[ctx:%p;self:%p]** Thread created : %p ****", context,
+	 xbt_os_thread_self(), context->thread);
+
+  DEBUG4
+      ("**[ctx:%p;self:%p]** Going to jail on creation_cond/mutex (%p,%p) ****",
+       context, xbt_os_thread_self(), creation_cond, creation_mutex);
+  xbt_os_cond_wait(creation_cond, creation_mutex);
+  DEBUG3("**[ctx:%p;self:%p]** Unlocking creation %p ****", context,
+	 xbt_os_thread_self(), creation_mutex);
+  xbt_os_mutex_unlock(creation_mutex);
+#else
+  makecontext(&(context->uc), (void (*)(void)) __context_wrapper, 1,
+	      context);
+#endif
+  return;
 }
 
-context_t __MSG_context_create(m_process_code_t code)
+/** 
+ * \param code a main function
+ * \param startup_func a function to call when running the context for
+ *      the first time and just before the main function \a code
+ * \param startup_arg the argument passed to the previous function (\a startup_func)
+ * \param cleanup_func a function to call when running the context, just after 
+        the termination of the main function \a code
+ * \param cleanup_arg the argument passed to the previous function (\a cleanup_func)
+ * \param argc first argument of function \a code
+ * \param argv seconde argument of function \a code
+ */
+xbt_context_t xbt_context_new(xbt_main_func_t code,
+			      void_f_pvoid_t startup_func,
+			      void *startup_arg,
+			      void_f_pvoid_t cleanup_func,
+			      void *cleanup_arg, int argc, char *argv[])
 {
-  context_t res = NULL;
+  xbt_context_t res = NULL;
 
-  res = CALLOC(1, sizeof(struct s_context));
+  res = xbt_new0(s_xbt_context_t, 1);
 
   res->code = code;
-  res->thread = CALLOC(1, sizeof(pthread_t));
-  if (pthread_mutex_init(&(res->mutex), NULL) != 0)
-    FAILURE("Mutex initialization error");
-  if (pthread_cond_init(&(res->cond), NULL) != 0)
-    FAILURE("Condition initialization error");
+#ifdef CONTEXT_THREADS
+  res->mutex = xbt_os_mutex_init();
+  res->cond = xbt_os_cond_init();
+#else
+
+  xbt_assert2(getcontext(&(res->uc)) == 0,
+	      "Error in context saving: %d (%s)", errno, strerror(errno));
+  res->uc.uc_link = NULL;
+  /*   res->uc.uc_link = &(current_context->uc); */
+  /* WARNING : when this context is over, the current_context (i.e. the 
+     father), is awaken... Theorically, the wrapper should prevent using 
+     this feature. */
+  res->uc.uc_stack.ss_sp = pth_skaddr_makecontext(res->stack, STACK_SIZE);
+  res->uc.uc_stack.ss_size =
+      pth_sksize_makecontext(res->stack, STACK_SIZE);
+#endif				/* CONTEXT_THREADS or not */
+
+  res->iwannadie = 0; /* useless but makes valgrind happy */
+
+  res->argc = argc;
+  res->argv = argv;
+  res->startup_func = startup_func;
+  res->startup_arg = startup_arg;
+  res->cleanup_func = cleanup_func;
+  res->cleanup_arg = cleanup_arg;
+  res->exception = xbt_new(ex_ctx_t, 1);
+  XBT_CTX_INITIALIZE(res->exception);
+
+  xbt_swag_insert(res, context_living);
 
   return res;
 }
 
-MSG_error_t __MSG_context_destroy(context_t * context)
+/** 
+ * Calling this function makes the current context yield. The context
+ * that scheduled it returns from xbt_context_schedule as if nothing
+ * had happened.
+ */
+void xbt_context_yield(void)
+{
+  __xbt_context_yield(current_context);
+}
+
+/** 
+ * \param context the winner
+ *
+ * Calling this function blocks the current context and schedule \a context.  
+ * When \a context will call xbt_context_yield, it will return
+ * to this function as if nothing had happened.
+ */
+void xbt_context_schedule(xbt_context_t context)
+{
+  DEBUG1("Scheduling %p", context);
+  xbt_assert0((current_context == init_context),
+	      "You are not supposed to run this function here!");
+  __xbt_context_yield(context);
+}
+
+/** 
+ * This function kill all existing context and free all the memory
+ * that has been allocated in this module.
+ */
+void xbt_context_exit(void)
 {
-  ASSERT(((context != NULL) && (*context != NULL)), "Invalid parameters");
+  xbt_context_t context = NULL;
 
-  FREE((*context)->thread);
-  pthread_mutex_destroy(&((*context)->mutex));
-  pthread_cond_destroy(&((*context)->cond));
+  xbt_context_empty_trash();
+  while ((context = xbt_swag_extract(context_living))) {
+    if (context != init_context) {
+      xbt_context_kill(context);
+    }
+  }
+  free(init_context->exception);
+  free(init_context);
+  init_context = current_context = NULL;
+
+  xbt_context_empty_trash();
+  xbt_swag_free(context_to_destroy);
+  xbt_swag_free(context_living);
+
+#ifdef CONTEXT_THREADS
+  xbt_os_mutex_destroy(creation_mutex);
+  xbt_os_cond_destroy(creation_cond);
+#endif
+}
 
-  FREE(*context);
-  *context = NULL;
+/** 
+ * \param context poor victim
+ *
+ * This function simply kills \a context... scarry isn't it ?
+ */
+void xbt_context_kill(xbt_context_t context)
+{
+  DEBUG1("Killing %p", context);
 
-  return MSG_OK;
+  context->iwannadie = 1;
+  DEBUG1("Scheduling %p", context);
+  __xbt_context_yield(context);
+  DEBUG1("End of Scheduling %p", context);
+
+  return;
 }
 
-MSG_error_t __MSG_context_yield(context_t context)
+/* @} */
+
+/* Stub of the stuff to interact with JAVA threads; not used in native lib */
+void xbt_context_set_jprocess(xbt_context_t context, void *jp)
 {
-  if (context) {
-    m_process_t self = msg_global->current_process;
-    pthread_mutex_lock(&(context->mutex));
-    pthread_cond_signal(&context->cond);
-    pthread_cond_wait(&context->cond, &context->mutex);
-    pthread_mutex_unlock(&(context->mutex));
-    msg_global->current_process = self;
-  }
-  return MSG_OK;
 }
-#endif /* HAVE_LIBPTHREAD */
-#endif /* USE_CONTEXT */
+void *xbt_context_get_jprocess(xbt_context_t context)
+{
+  return NULL;
+}
+
+void xbt_context_set_jmutex(xbt_context_t context, void *jm)
+{
+}
+void *xbt_context_get_jmutex(xbt_context_t context)
+{
+  return NULL;
+}
+
+void xbt_context_set_jcond(xbt_context_t context, void *jc)
+{
+}
+void *xbt_context_get_jcond(xbt_context_t context)
+{
+  return NULL;
+}
+
+void xbt_context_set_jenv(xbt_context_t context, void *je)
+{
+}
+void *xbt_context_get_jenv(xbt_context_t context)
+{
+  return NULL;
+}