/* 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 "simgrid/modelchecker.h"
+#include "src/internal_config.h"
#include "src/kernel/context/context_private.hpp"
#include "src/simix/ActorImpl.hpp"
#include "src/simix/smx_private.hpp"
-#include "ContextSwapped.hpp"
+#include "src/kernel/context/ContextSwapped.hpp"
+
+#ifdef _WIN32
+#include <malloc.h>
+#include <windows.h>
+#else
+#include <sys/mman.h>
+#endif
+
+#ifdef __MINGW32__
+#define _aligned_malloc __mingw_aligned_malloc
+#define _aligned_free __mingw_aligned_free
+#endif /*MINGW*/
+
+#if HAVE_VALGRIND_H
+#include <valgrind/valgrind.h>
+#endif
XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(simix_context);
SwappedContext* SwappedContext::maestro_context_ = nullptr;
+SwappedContext::SwappedContext(std::function<void()> code, void_pfn_smxprocess_t cleanup_func, smx_actor_t process)
+ : Context(std::move(code), cleanup_func, process)
+{
+ if (has_code()) {
+ if (smx_context_guard_size > 0 && not MC_is_active()) {
+
+#if !defined(PTH_STACKGROWTH) || (PTH_STACKGROWTH != -1)
+ xbt_die(
+ "Stack overflow protection is known to be broken on your system: you stacks grow upwards (or detection is "
+ "broken). "
+ "Please disable stack guards with --cfg=contexts:guard-size:0");
+ /* 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. */
+#endif
+
+ size_t size = smx_context_stack_size + smx_context_guard_size;
+#if SIMGRID_HAVE_MC
+ /* Cannot use posix_memalign when SIMGRID_HAVE_MC. Align stack by hand, and save the
+ * pointer returned by xbt_malloc0. */
+ char* alloc = (char*)xbt_malloc0(size + xbt_pagesize);
+ stack_ = alloc - ((uintptr_t)alloc & (xbt_pagesize - 1)) + xbt_pagesize;
+ *((void**)stack_ - 1) = alloc;
+#elif !defined(_WIN32)
+ if (posix_memalign(&this->stack_, xbt_pagesize, size) != 0)
+ xbt_die("Failed to allocate stack.");
+#else
+ this->stack_ = _aligned_malloc(size, xbt_pagesize);
+#endif
+
+#ifndef _WIN32
+ if (mprotect(this->stack_, smx_context_guard_size, PROT_NONE) == -1) {
+ xbt_die(
+ "Failed to protect stack: %s.\n"
+ "If you are running a lot of actors, you may be exceeding the amount of mappings allowed per process.\n"
+ "On Linux systems, change this value with sudo sysctl -w vm.max_map_count=newvalue (default value: 65536)\n"
+ "Please see http://simgrid.gforge.inria.fr/simgrid/latest/doc/html/options.html#options_virt for more "
+ "info.",
+ strerror(errno));
+ /* This is fatal. We are going to fail at some point when we try reusing this. */
+ }
+#endif
+ this->stack_ = (char*)this->stack_ + smx_context_guard_size;
+ } else {
+ this->stack_ = xbt_malloc0(smx_context_stack_size);
+ }
+
+#if HAVE_VALGRIND_H
+ unsigned int valgrind_stack_id =
+ VALGRIND_STACK_REGISTER(this->stack_, (char*)this->stack_ + smx_context_stack_size);
+ memcpy((char*)this->stack_ + smx_context_usable_stack_size, &valgrind_stack_id, sizeof valgrind_stack_id);
+#endif
+ }
+}
+
+SwappedContext::~SwappedContext()
+{
+ if (stack_ == nullptr)
+ return;
+
+#if HAVE_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 && not 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 */
+ }
+#if SIMGRID_HAVE_MC
+ /* Retrieve the saved pointer. See SIMIX_context_stack_new above. */
+ stack_ = *((void**)stack_ - 1);
+#endif
+ }
+#endif /* not windows */
+
+ xbt_free(stack_);
+}
+
void SwappedContext::suspend()
{
/* determine the next context */
