#include "xbt/xbt_os_thread.h"
#include "xbt/ex_interface.h"
-#ifdef CONTEXT_THREADS
- /* This file (context.c) is only loaded in libsimgrid, not libgras.
- * xbt_os_thread is only loaded in libgras explicitly, and we need it in
- * libsimgrid, but only when it is the backend used to implement the
- * xbt_context. So, do load it on need.
- */
-#include "xbt/xbt_os_thread.c"
-#else
-/* if not, load stubs so that all symbols get resolved anyway */
-#include "xbt/xbt_os_thread_stubs.c"
-#endif
-
XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_ctx, xbt, "Context");
#define VOIRP(expr) DEBUG1(" {" #expr " = %p }", expr)
static xbt_os_cond_t creation_cond;
#endif
-static void __context_exit(xbt_context_t context, int value);
-static void __xbt_context_yield(xbt_context_t context)
-{
- xbt_assert0(current_context, "You have to call context_init() first.");
-
- DEBUG2
- ("--------- current_context (%p) is yielding to context(%p) ---------",
- current_context, 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);
- VOIRP(context);
+/********************/
+/* Module init/exit */
+/********************/
+#ifndef CONTEXT_THREADS
+/* callback: context fetching (used only with ucontext, os_thread deal with it
+ for us otherwise) */
+static ex_ctx_t *_context_ex_ctx(void) {
+ return current_context->exception;
+}
- if (context)
- VOIRP(context->save);
+/* callback: termination */
+static void _context_ex_terminate(xbt_ex_t * e) {
+ xbt_ex_display(e);
- if (context) {
+ abort();
+ /* FIXME: there should be a configuration variable to
+ choose to kill everyone or only this one */
+}
+#endif
- int return_value = 0;
+/** \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);
- if (context->save == NULL) {
+ init_context->iwannadie = 0; /* useless but makes valgrind happy */
+ 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();
+#else
+ 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;
+#endif
+ }
+}
- 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);
+/**
+ * This function kill all existing context and free all the memory
+ * that has been allocated in this module.
+ */
+void xbt_context_exit(void)
+{
+ xbt_context_t context = NULL;
+ xbt_context_empty_trash();
+ while ((context = xbt_swag_extract(context_living))) {
+ if (context != init_context) {
+ xbt_context_kill(context);
}
}
+#ifdef CONTEXT_THREADS
+ xbt_os_mutex_destroy(creation_mutex);
+ xbt_os_cond_destroy(creation_cond);
+#else
+ free(init_context->exception);
#endif
- if (current_context->iwannadie)
- __context_exit(current_context, 1);
+ free(init_context);
+ init_context = current_context = NULL;
+
+ xbt_context_empty_trash();
+ xbt_swag_free(context_to_destroy);
+ xbt_swag_free(context_living);
- return;
}
-static void xbt_context_free(xbt_context_t context)
+/*******************************/
+/* Object creation/destruction */
+/*******************************/
+/**
+ * \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(const char *name,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[])
{
- 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);
+ xbt_context_t res = NULL;
- xbt_os_thread_join(context->thread, NULL);
+ res = xbt_new0(s_xbt_context_t, 1);
- 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);
+ res->code = code;
+ res->name = xbt_strdup(name);
+#ifdef CONTEXT_THREADS
+ res->mutex = xbt_os_mutex_init();
+ res->cond = xbt_os_cond_init();
+#else
- context->thread = NULL;
- context->mutex = NULL;
- context->cond = NULL;
-#endif
+ 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);
+
+ res->exception = xbt_new(ex_ctx_t, 1);
+ XBT_CTX_INITIALIZE(res->exception);
+#endif /* CONTEXT_THREADS or not */
- if (context->exception)
- free(context->exception);
+ res->iwannadie = 0; /* useless but makes valgrind happy */
- free(context);
- return;
-}
+ 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;
-static void __context_exit(xbt_context_t context, int value)
-{
- int i;
+ xbt_swag_insert(res, context_living);
- DEBUG1("--------- %p is exiting ---------", context);
+ return res;
+}
- DEBUG0("Calling cleanup functions");
- if (context->cleanup_func) {
- DEBUG0("Calling cleanup function");
- context->cleanup_func(context->cleanup_arg);
- }
+/* Scenario for the end of a context:
+ *
+ * CASE 1: death after end of function
+ * __context_wrapper, called by os thread, calls xbt_context_stop after user code stops
+ * xbt_context_stop calls user cleanup_func if any (in context settings),
+ * add current to trashbin
+ * yields back to maestro (destroy os thread on need)
+ * From time to time, maestro calls xbt_context_empty_trash,
+ * which maps xbt_context_free on the content
+ * xbt_context_free frees some more memory,
+ * joins os thread
+ *
+ * CASE 2: brutal death
+ * xbt_context_kill (from any context)
+ * set context->wannadie to 1
+ * yields to the context
+ * the context is awaken in the middle of __yield.
+ * At the end of it, it checks that wannadie == 1, and call xbt_context_stop
+ * (same than first case afterward)
+ */
+/* Argument must be stopped first -- runs in maestro context */
+static void xbt_context_free(xbt_context_t context) {
+ int i;
+
+ if (!context)
+ return;
+ DEBUG1("Freeing %p", context);
+ free(context->name);
+
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");
+#ifdef CONTEXT_THREADS
+ DEBUG1("\t joining %p", (void *) context->thread);
- DEBUG0("Yielding");
+ xbt_os_thread_join(context->thread, NULL);
-#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
+ xbt_os_mutex_destroy(context->mutex);
+ xbt_os_cond_destroy(context->cond);
+
+ context->thread = NULL;
+ context->mutex = NULL;
+ context->cond = NULL;
#else
- __xbt_context_yield(context);
+ if (context->exception)
+ free(context->exception);
#endif
- xbt_assert0(0, "You can't be here!");
+
+ free(context);
+ return;
}
+/************************/
+/* Start/stop a context */
+/************************/
+static void xbt_context_stop(int retvalue);
+static void __xbt_context_yield(xbt_context_t context);
+
static void *__context_wrapper(void *c)
{
xbt_context_t context = current_context;
DEBUG0("Calling the main function");
- __context_exit(context, (context->code) (context->argc, context->argv));
+ xbt_context_stop((context->code) (context->argc, context->argv));
return NULL;
}
-
-/* callback: context fetching */
-static ex_ctx_t *__context_ex_ctx(void)
-{
- return current_context->exception;
-}
-
-/* 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();
- */
-}
-
-/** \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
- }
-}
-
-/** 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
*
{
#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);
+ context->thread = xbt_os_thread_create(context->name,__context_wrapper, context);
DEBUG3("**[ctx:%p;self:%p]** Thread created : %p ****", context,
xbt_os_thread_self(), context->thread);
return;
}
-/**
- * \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
+/* Stops current context: calls user's cleanup function, kills os thread, and yields back to maestro */
+static void xbt_context_stop(int retvalue) {
+ DEBUG1("--------- %p is exiting ---------", current_context);
+
+ if (current_context->cleanup_func) {
+ DEBUG0("Calling cleanup function");
+ current_context->cleanup_func(current_context->cleanup_arg);
+ }
+
+ DEBUG0("Putting context in the to_destroy set");
+ xbt_swag_remove(current_context, context_living);
+ xbt_swag_insert(current_context, context_to_destroy);
+
+ DEBUG0("Yielding");
+
+#ifdef CONTEXT_THREADS
+ DEBUG2("[%p] **** Locking %p ****", current_context, current_context->mutex);
+ xbt_os_mutex_lock(current_context->mutex);
+ DEBUG1("[%p] **** Releasing the prisonner ****", current_context);
+ xbt_os_cond_signal(current_context->cond);
+ DEBUG2("[%p] **** Unlocking individual %p ****", current_context,
+ current_context->mutex);
+ xbt_os_mutex_unlock(current_context->mutex);
+ DEBUG1("[%p] **** Exiting ****", current_context);
+ xbt_os_thread_exit(NULL); // We should provide return value in case other wants it
+#else
+ __xbt_context_yield(current_context);
+#endif
+ THROW_IMPOSSIBLE;
+}
+
+
+
+/** Garbage collection
+ *
+ * Should be called some time to time to free the memory allocated for contexts
+ * that have finished executing their main functions.
*/
-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[])
+void xbt_context_empty_trash(void)
{
- xbt_context_t res = NULL;
+ 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);
+}
- res = xbt_new0(s_xbt_context_t, 1);
+/*********************/
+/* context switching */
+/*********************/
- res->code = code;
+static void __xbt_context_yield(xbt_context_t context)
+{
#ifdef CONTEXT_THREADS
- res->mutex = xbt_os_mutex_init();
- res->cond = xbt_os_cond_init();
-#else
+ xbt_context_t self;
+#endif
+xbt_assert0(current_context, "You have to call context_init() first.");
+ xbt_assert0(context,"Invalid argument");
- 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 */
+ if (current_context == context) {
+ DEBUG1("--------- current_context (%p) is yielding back to maestro ---------",
+ context);
+ } else {
+ DEBUG2("--------- current_context (%p) is yielding to context(%p) ---------",
+ current_context, context);
+ }
- res->iwannadie = 0; /* useless but makes valgrind happy */
+#ifdef CONTEXT_THREADS
+ 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;
- 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);
+#else /* use SUSv2 contexts */
+ VOIRP(current_context);
+ VOIRP(current_context->save);
- xbt_swag_insert(res, context_living);
+ VOIRP(context);
+ VOIRP(context->save);
- return res;
+ 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);
+ }
+#endif
+ if (current_context->iwannadie)
+ xbt_context_stop(1);
+
+ return;
}
+
+
+
+
/**
* Calling this function makes the current context yield. The context
* that scheduled it returns from xbt_context_schedule as if nothing
* had happened.
+ *
+ * Only the processes can call this function, giving back the control
+ * to the maestro
*/
void xbt_context_yield(void)
{
* 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.
+ *
+ * Only the maestro can call this function to run a given process.
*/
void xbt_context_schedule(xbt_context_t context)
{
__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)
-{
- xbt_context_t context = NULL;
-
- 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
-}
/**
* \param context poor victim
return;
}
-/* @} */
+/* Java cruft I'm gonna kill in the next cleanup round */
+void xbt_context_set_jprocess(xbt_context_t context, void *jp){}
+void* xbt_context_get_jprocess(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;}
-/* 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)
-{
-}
-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;
-}
+/* @} */
