X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/907e0ad42ebe9ac4074648201519ecc10d1f8812..a78b29bf9787d3544aadaa7970e349cd9810a81b:/src/simix/smx_context.c

diff --git a/src/simix/smx_context.c b/src/simix/smx_context.c
index 281c2d886f..e5e48ce071 100644
--- a/src/simix/smx_context.c
+++ b/src/simix/smx_context.c
@@ -10,12 +10,24 @@
 #include "xbt/log.h"
 #include "xbt/swag.h"
 #include "private.h"
-#include "simix/smx_context_private.h"
+#include "simix/context.h"
+#include "gras_config.h"
 
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_context, simix,
                                 "Context switching mecanism");
 
-SIMIX_ctx_factory_initializer_t factory_initializer_to_use = NULL;
+char* smx_context_factory_name = NULL; /* factory name specified by --cfg=contexts/factory:value */
+smx_ctx_factory_initializer_t smx_factory_initializer_to_use = NULL;
+int smx_context_stack_size = 128 * 1024;
+
+#ifdef CONTEXT_THREADS
+__thread smx_context_t smx_current_context;
+#else
+smx_context_t smx_current_context;
+#endif
+
+static int smx_parallel_contexts = 1;
+static int smx_parallel_threshold = 1;
 
 /** 
  * This function is called by SIMIX_global_init() to initialize the context module.
@@ -23,17 +35,39 @@ SIMIX_ctx_factory_initializer_t factory_initializer_to_use = NULL;
 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) */
-    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);
+    /* select the context factory to use to create the contexts */
+    if (smx_factory_initializer_to_use) {
+      (*smx_factory_initializer_to_use)(&(simix_global->context_factory));
+    }
+    else { /* use the factory specified by --cfg=contexts/factory:value */
+
+      if (smx_context_factory_name == NULL) {
+        /* use the default factory */
+#ifdef CONTEXT_UCONTEXT
+        SIMIX_ctx_sysv_factory_init(&simix_global->context_factory);
+#else
+        SIMIX_ctx_thread_factory_init(&simix_global->context_factory);
+#endif
+      }
+      else if (!strcmp(smx_context_factory_name, "ucontext")) {
+        /* use ucontext */
+#ifdef CONTEXT_UCONTEXT
+        SIMIX_ctx_sysv_factory_init(&simix_global->context_factory);
 #else
-#error ERROR [__FILE__, line __LINE__]: no context implementation specified.
+        xbt_die("The ontext factory 'ucontext' unavailable on your system");
 #endif
+      }
+      else if (!strcmp(smx_context_factory_name, "thread")) {
+	/* use os threads (either pthreads or windows ones) */
+        SIMIX_ctx_thread_factory_init(&simix_global->context_factory);
+      }
+      else if (!strcmp(smx_context_factory_name, "raw")) {
+	/* use raw contexts */
+	SIMIX_ctx_raw_factory_init(&simix_global->context_factory);
+      }
+      else {
+        xbt_die("Invalid context factory specified");
+      }
     }
   }
 }
@@ -50,4 +84,73 @@ void SIMIX_context_mod_exit(void)
     finalize_factory = simix_global->context_factory->finalize;
     (*finalize_factory) (&simix_global->context_factory);
   }
+  xbt_dict_remove((xbt_dict_t) _surf_cfg_set,"contexts/factory");
+}
+
+/**
+ * \brief Sets the number of parallel threads to use
+ * for the user contexts.
+ *
+ * This function should be called before initializing SIMIX.
+ * A value of 1 means no parallelism.
+ * If the value is greater than 1, the thread support must be enabled.
+ *
+ * \param nb_threads the number of threads to use
+ */
+XBT_INLINE void SIMIX_context_set_nthreads(int nb_threads) {
+
+  xbt_assert(nb_threads > 0, "Invalid number of parallel threads: %d", nb_threads);
+
+  if (nb_threads > 1) {
+#ifndef CONTEXT_THREADS
+    THROWF(arg_error, 0, "No thread support for parallel context execution");
+#endif
+  }
+
+  smx_parallel_contexts = nb_threads;
 }
+
+/**
+ * \brief Returns the number of parallel threads used
+ * for the user contexts.
+ * \return the number of threads (1 means no parallelism)
+ */
+XBT_INLINE int SIMIX_context_get_nthreads(void) {
+  return smx_parallel_contexts;
+}
+
+/**
+ * \brief Returns whether some parallel threads are used
+ * for the user contexts.
+ * \return 1 if parallelism is used
+ */
+XBT_INLINE int SIMIX_context_is_parallel(void) {
+  return smx_parallel_contexts > 1;
+}
+
+/**
+ * \brief Sets the threshold above which user processes are run in parallel.
+ *
+ * If the number of threads is set to 1, there is no parallelism and this
+ * threshold has no effect.
+ *
+ * \param threshold when the number of user processes ready to run is above
+ * this threshold, they are run in parallel
+ */
+XBT_INLINE void SIMIX_context_set_parallel_threshold(int threshold) {
+  smx_parallel_threshold = threshold;
+}
+
+/**
+ * \brief Returns the threshold above which user processes are run in parallel.
+ *
+ * If the number of threads is set to 1, there is no parallelism and this
+ * threshold has no effect.
+ *
+ * \return when the number of user processes ready to run is above
+ * this threshold, they are run in parallel
+ */
+XBT_INLINE int SIMIX_context_get_parallel_threshold(void) {
+  return smx_parallel_threshold;
+}
+