X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/45c3f1cfee86fb48c96d53f8267f99b6db6e3d7a..5fc72d28104dca5e9f2fb0d2bb047c7277a7999f:/src/simix/smx_context.c

diff --git a/src/simix/smx_context.c b/src/simix/smx_context.c
index 214ea7197a..e447ed3e98 100644
--- a/src/simix/smx_context.c
+++ b/src/simix/smx_context.c
@@ -1,6 +1,6 @@
 /* a fast and simple context switching library                              */
 
-/* Copyright (c) 2009-2014. The SimGrid Team.
+/* Copyright (c) 2009-2015. The SimGrid Team.
  * All rights reserved.                                                     */
 
 /* This program is free software; you can redistribute it and/or modify it
@@ -13,16 +13,36 @@
 #include "smx_private.h"
 #include "simgrid/sg_config.h"
 #include "internal_config.h"
+#include "simgrid/modelchecker.h"
+
+
+#ifdef _WIN32
+#include <windows.h>
+#include <malloc.h>
+#else
+#include <sys/mman.h>
+#endif
+
+#ifdef __MINGW32__ 
+#define _aligned_malloc __mingw_aligned_malloc 
+#define _aligned_free  __mingw_aligned_free 
+#endif //MINGW
+
+#ifdef HAVE_VALGRIND_VALGRIND_H
+# include <valgrind/valgrind.h>
+#endif
 
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_context, simix,
                                 "Context switching mechanism");
 
 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;
+int smx_context_stack_size;
 int smx_context_stack_size_was_set = 0;
+int smx_context_guard_size;
+int smx_context_guard_size_was_set = 0;
 #ifdef HAVE_THREAD_LOCAL_STORAGE
-static __thread smx_context_t smx_current_context_parallel;
+static XBT_THREAD_LOCAL smx_context_t smx_current_context_parallel;
 #else
 static xbt_os_thread_key_t smx_current_context_key = 0;
 #endif
@@ -64,6 +84,12 @@ void SIMIX_context_mod_init(void)
         /* use raw contexts */
         SIMIX_ctx_raw_factory_init(&simix_global->context_factory);
       }
+#endif
+#ifdef HAVE_BOOST_CONTEXT
+      else if (!strcmp(smx_context_factory_name, "boost")) {
+        /* use Boost.Context */
+        SIMIX_ctx_boost_factory_init(&simix_global->context_factory);
+      }
 #endif
       else {
         XBT_ERROR("Invalid context factory specified. Valid factories on this machine:");
@@ -99,6 +125,91 @@ void SIMIX_context_mod_exit(void)
   xbt_dict_remove((xbt_dict_t) _sg_cfg_set,"contexts/factory");
 }
 
+void *SIMIX_context_stack_new(void)
+{
+  void *stack;
+
+  /* FIXME: current code for stack overflow protection assumes that stacks are
+   * growing downward (PTH_STACKGROWTH == -1).  Protected pages need to be put
+   * after the stack when PTH_STACKGROWTH == 1. */
+
+  if (smx_context_guard_size > 0 && !MC_is_active()) {
+
+#if defined(_XBT_WIN32) || (PTH_STACKGROWTH != -1)
+    static int warned_once = 0;
+    if (!warned_once) {
+      XBT_WARN("Stack overflow protection is known to be broken on your system.  Either you're on Windows or PTH_STACKGROWTH != -1 (current value is %d).",
+               PTH_STACKGROWTH);
+      warned_once = 1;
+    }
+#endif
+
+    size_t size = smx_context_stack_size + smx_context_guard_size;
+#ifdef HAVE_MC
+    /* Cannot use posix_memalign when HAVE_MC. Align stack by hand, and save the
+     * pointer returned by xbt_malloc0. */
+    char *alloc = xbt_malloc0(size + xbt_pagesize);
+    stack = alloc - ((uintptr_t)alloc & (xbt_pagesize - 1)) + xbt_pagesize;
+    *((void **)stack - 1) = alloc;
+#elif !defined(_XBT_WIN32)
+    if (posix_memalign(&stack, xbt_pagesize, size) != 0)
+      xbt_die("Failed to allocate stack.");
+#else
+    stack = _aligned_malloc(size, xbt_pagesize);
+#endif
+
+#ifndef _XBT_WIN32
+    if (mprotect(stack, smx_context_guard_size, PROT_NONE) == -1) {
+      xbt_die("Failed to protect stack: %s", strerror(errno));
+      /* This is fatal. We are going to fail at some point when
+         we tryi reusing this. */
+    }
+#endif
+    stack = (char *)stack + smx_context_guard_size;
+  } else {
+    stack = xbt_malloc0(smx_context_stack_size);
+  }
+
+#ifdef HAVE_VALGRIND_VALGRIND_H
+  unsigned int valgrind_stack_id =
+    VALGRIND_STACK_REGISTER(stack, (char *)stack + smx_context_stack_size);
+  memcpy((char *)stack + smx_context_usable_stack_size, &valgrind_stack_id,
+         sizeof valgrind_stack_id);
+#endif
+
+  return stack;
+}
+
+void SIMIX_context_stack_delete(void *stack)
+{
+  if (!stack)
+    return;
+
+#ifdef HAVE_VALGRIND_VALGRIND_H
+  unsigned int valgrind_stack_id;
+  memcpy(&valgrind_stack_id, (char *)stack + smx_context_usable_stack_size,
+         sizeof valgrind_stack_id);
+  VALGRIND_STACK_DEREGISTER(valgrind_stack_id);
+#endif
+
+#ifndef WIN32
+  if (smx_context_guard_size > 0 && !MC_is_active()) {
+    stack = (char *)stack - smx_context_guard_size;
+    if (mprotect(stack, smx_context_guard_size,
+                 PROT_READ | PROT_WRITE) == -1) {
+      XBT_WARN("Failed to remove page protection: %s", strerror(errno));
+      /* try to pursue anyway */
+    }
+#ifdef HAVE_MC
+    /* Retrieve the saved pointer.  See SIMIX_context_stack_new above. */
+    stack = *((void **)stack - 1);
+#endif
+  }
+#endif
+
+  xbt_free(stack);
+}
+
 /**
  * \brief Returns whether some parallel threads are used
  * for the user contexts.