1 /* a fast and simple context switching library */
3 /* Copyright (c) 2009-2021. The SimGrid Team. All rights reserved. */
5 /* This program is free software; you can redistribute it and/or modify it
6 * under the terms of the license (GNU LGPL) which comes with this package. */
8 #include "src/internal_config.h"
9 #include "src/kernel/EngineImpl.hpp"
10 #include "src/smpi/include/private.hpp"
11 #include "xbt/config.hpp"
13 #include <initializer_list>
16 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_context, simix, "Context switching mechanism");
18 constexpr std::initializer_list<std::pair<const char*, simgrid::kernel::context::ContextFactoryInitializer>>
21 {"raw", &simgrid::kernel::context::raw_factory},
23 #if HAVE_UCONTEXT_CONTEXTS
24 {"ucontext", &simgrid::kernel::context::sysv_factory},
26 #if HAVE_BOOST_CONTEXTS
27 {"boost", &simgrid::kernel::context::boost_factory},
29 {"thread", &simgrid::kernel::context::thread_factory},
32 static_assert(context_factories.size() > 0, "No context factories are enabled for this build");
34 // Create the list of possible contexts:
36 std::string contexts_list()
40 for (auto const& factory : context_factories) {
41 res += sep + factory.first;
47 static simgrid::config::Flag<std::string>
48 context_factory_name("contexts/factory", (std::string("Possible values: ") + contexts_list()).c_str(),
49 context_factories.begin()->first);
51 int SIMIX_context_is_parallel() // XBT_ATTRIB_DEPRECATED_v333
53 return simgrid::kernel::context::is_parallel();
56 int SIMIX_context_get_nthreads() // XBT_ATTRIB_DEPRECATED_v333
58 return simgrid::kernel::context::get_nthreads();
61 void SIMIX_context_set_nthreads(int nb_threads) // XBT_ATTRIB_DEPRECATED_v333
63 simgrid::kernel::context::set_nthreads(nb_threads);
66 e_xbt_parmap_mode_t SIMIX_context_get_parallel_mode() // XBT_ATTRIB_DEPRECATED_v333
68 return simgrid::kernel::context::get_parallel_mode();
71 void SIMIX_context_set_parallel_mode(e_xbt_parmap_mode_t mode) // XBT_ATTRIB_DEPRECATED_v333
73 simgrid::kernel::context::set_parallel_mode(mode);
79 void EngineImpl::context_mod_init() const
81 xbt_assert(not instance_->has_context_factory());
83 #if HAVE_SMPI && (defined(__APPLE__) || defined(__NetBSD__))
84 smpi_init_options_internal(false);
85 std::string priv = config::get_value<std::string>("smpi/privatization");
86 if (context_factory_name == "thread" && (priv == "dlopen" || priv == "yes" || priv == "default" || priv == "1")) {
87 XBT_WARN("dlopen+thread broken on Apple and BSD. Switching to raw contexts.");
88 context_factory_name = "raw";
92 #if HAVE_SMPI && defined(__FreeBSD__)
93 smpi_init_options_internal(false);
94 if (context_factory_name == "thread" && config::get_value<std::string>("smpi/privatization") != "no") {
95 XBT_WARN("mmap broken on FreeBSD, but dlopen+thread broken too. Switching to dlopen+raw contexts.");
96 context_factory_name = "raw";
100 /* select the context factory to use to create the contexts */
101 if (context::factory_initializer != nullptr) { // Give Java a chance to hijack the factory mechanism
102 instance_->set_context_factory(context::factory_initializer());
105 /* use the factory specified by --cfg=contexts/factory:value */
106 for (auto const& factory : context_factories)
107 if (context_factory_name == factory.first) {
108 instance_->set_context_factory(factory.second());
112 if (not instance_->has_context_factory()) {
113 XBT_ERROR("Invalid context factory specified. Valid factories on this machine:");
114 #if HAVE_RAW_CONTEXTS
115 XBT_ERROR(" raw: high performance context factory implemented specifically for SimGrid");
117 XBT_ERROR(" (raw contexts were disabled at compilation time on this machine -- check configure logs for details)");
119 #if HAVE_UCONTEXT_CONTEXTS
120 XBT_ERROR(" ucontext: classical system V contexts (implemented with makecontext, swapcontext and friends)");
122 XBT_ERROR(" (ucontext was disabled at compilation time on this machine -- check configure logs for details)");
124 #if HAVE_BOOST_CONTEXTS
125 XBT_ERROR(" boost: this uses the boost libraries context implementation");
127 XBT_ERROR(" (boost was disabled at compilation time on this machine -- check configure logs for details. Did you "
128 "install the libboost-context-dev package?)");
130 XBT_ERROR(" thread: slow portability layer using pthreads as provided by gcc");
131 xbt_die("Please use a valid factory.");
134 } // namespace kernel
135 } // namespace simgrid