/* a fast and simple context switching library */
-/* Copyright (c) 2009-2018. The SimGrid Team. All rights reserved. */
+/* Copyright (c) 2009-2019. The SimGrid Team. 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 "simgrid/modelchecker.h"
-#include "src/internal_config.h"
#include "src/simix/smx_private.hpp"
#include "xbt/config.hpp"
#include <thread>
-#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*/
-
-#if HAVE_VALGRIND_H
-# include <valgrind/valgrind.h>
-#endif
-
XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_context, simix, "Context switching mechanism");
static std::pair<const char*, simgrid::kernel::context::ContextFactoryInitializer> context_factories[] = {
context_factories[0].first);
unsigned smx_context_stack_size;
-int smx_context_stack_size_was_set = 0;
unsigned smx_context_guard_size;
-int smx_context_guard_size_was_set = 0;
-static thread_local smx_context_t smx_current_context;
static int smx_parallel_contexts = 1;
static int smx_parallel_threshold = 2;
static e_xbt_parmap_mode_t smx_parallel_synchronization_mode = XBT_PARMAP_DEFAULT;
{
xbt_assert(simix_global->context_factory == nullptr);
- smx_context_stack_size_was_set = not simgrid::config::is_default("contexts/stack-size");
- smx_context_guard_size_was_set = not simgrid::config::is_default("contexts/guard-size");
-
#if HAVE_SMPI && (defined(__APPLE__) || defined(__NetBSD__))
std::string priv = simgrid::config::get_value<std::string>("smpi/privatization");
if (context_factory_name == "thread" && (priv == "dlopen" || priv == "yes" || priv == "default" || priv == "1")) {
simix_global->context_factory = nullptr;
}
-void *SIMIX_context_stack_new()
-{
- void *stack;
-
- 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(&stack, xbt_pagesize, size) != 0)
- xbt_die("Failed to allocate stack.");
-#else
- stack = _aligned_malloc(size, xbt_pagesize);
-#endif
-
-#ifndef _WIN32
- if (mprotect(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
- stack = (char *)stack + smx_context_guard_size;
- } else {
- stack = xbt_malloc0(smx_context_stack_size);
- }
-
-#if HAVE_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 (not stack)
- 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);
-}
-
/** @brief Returns whether some parallel threads are used for the user contexts. */
int SIMIX_context_is_parallel() {
return smx_parallel_contexts > 1;
void SIMIX_context_set_parallel_mode(e_xbt_parmap_mode_t mode) {
smx_parallel_synchronization_mode = mode;
}
-
-/**
- * @brief Returns the current context of this thread.
- * @return the current context of this thread
- */
-smx_context_t SIMIX_context_get_current()
-{
- return smx_current_context;
-}
-
-/**
- * @brief Sets the current context of this thread.
- * @param context the context to set
- */
-void SIMIX_context_set_current(smx_context_t context)
-{
- smx_current_context = context;
-}
