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Delay creation of parmap for boost contexts too.
[simgrid.git] / src / kernel / context / ContextBoost.cpp
1 /* Copyright (c) 2015-2017. The SimGrid Team. All rights reserved.          */
2
3 /* This program is free software; you can redistribute it and/or modify it
4  * under the terms of the license (GNU LGPL) which comes with this package. */
5
6 #include <cstdint>
7
8 #include <functional>
9 #include <utility>
10 #include <vector>
11
12 #include <boost/context/all.hpp>
13
14 #include <xbt/log.h>
15 #include <xbt/xbt_os_thread.h>
16
17 #include "src/simix/smx_private.h"
18 #include "src/internal_config.h"
19 #include "src/kernel/context/ContextBoost.hpp"
20
21 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(simix_context);
22
23 namespace simgrid {
24 namespace kernel {
25 namespace context {
26
27 class BoostSerialContext : public BoostContext {
28 public:
29   BoostSerialContext(std::function<void()> code,
30       void_pfn_smxprocess_t cleanup_func,
31       smx_actor_t process)
32     : BoostContext(std::move(code), cleanup_func, process) {}
33   void stop() override;
34   void suspend() override;
35 };
36
37 #if HAVE_THREAD_CONTEXTS
38 class BoostParallelContext : public BoostContext {
39 public:
40   BoostParallelContext(std::function<void()> code,
41       void_pfn_smxprocess_t cleanup_func,
42       smx_actor_t process)
43     : BoostContext(std::move(code), cleanup_func, process) {}
44   void stop() override;
45   void suspend() override;
46   void resume() override;
47 };
48 #endif
49
50 // BoostContextFactory
51
52 bool BoostContext::parallel_                             = false;
53 simgrid::xbt::Parmap<smx_actor_t>* BoostContext::parmap_ = nullptr;
54 uintptr_t BoostContext::threads_working_                 = 0;
55 xbt_os_thread_key_t BoostContext::worker_id_key_;
56 unsigned long BoostContext::process_index_   = 0;
57 BoostContext* BoostContext::maestro_context_ = nullptr;
58 std::vector<BoostContext*> BoostContext::workers_context_;
59
60 BoostContextFactory::BoostContextFactory()
61   : ContextFactory("BoostContextFactory")
62 {
63   BoostContext::parallel_ = SIMIX_context_is_parallel();
64   if (BoostContext::parallel_) {
65 #if HAVE_THREAD_CONTEXTS
66     BoostContext::parmap_ = nullptr;
67     BoostContext::workers_context_.clear();
68     BoostContext::workers_context_.resize(SIMIX_context_get_nthreads(), nullptr);
69     BoostContext::maestro_context_ = nullptr;
70     xbt_os_thread_key_create(&BoostContext::worker_id_key_);
71 #else
72     xbt_die("No thread support for parallel context execution");
73 #endif
74   }
75 }
76
77 BoostContextFactory::~BoostContextFactory()
78 {
79 #if HAVE_THREAD_CONTEXTS
80   delete BoostContext::parmap_;
81   BoostContext::parmap_ = nullptr;
82   BoostContext::workers_context_.clear();
83 #endif
84 }
85
86 smx_context_t BoostContextFactory::create_context(std::function<void()> code, void_pfn_smxprocess_t cleanup_func,
87                                                   smx_actor_t process)
88 {
89   BoostContext* context = nullptr;
90   if (BoostContext::parallel_)
91 #if HAVE_THREAD_CONTEXTS
92     context = this->new_context<BoostParallelContext>(std::move(code), cleanup_func, process);
93 #else
94     xbt_die("No support for parallel execution");
95 #endif
96   else
97     context = this->new_context<BoostSerialContext>(std::move(code), cleanup_func, process);
98   return context;
99 }
100
101 void BoostContextFactory::run_all()
102 {
103 #if HAVE_THREAD_CONTEXTS
104   if (BoostContext::parallel_) {
105     BoostContext::threads_working_ = 0;
106     if (not BoostContext::parmap_)
107       BoostContext::parmap_ =
108           new simgrid::xbt::Parmap<smx_actor_t>(SIMIX_context_get_nthreads(), SIMIX_context_get_parallel_mode());
109     BoostContext::parmap_->apply(
110         [](smx_actor_t process) {
111           BoostContext* context = static_cast<BoostContext*>(process->context);
112           return context->resume();
113         },
114         simix_global->process_to_run);
115   } else
116 #endif
117   {
118     if (simix_global->process_to_run.empty())
119       return;
120     smx_actor_t first_process    = simix_global->process_to_run.front();
121     BoostContext::process_index_ = 1;
122     /* execute the first process */
123     static_cast<BoostContext*>(first_process->context)->resume();
124   }
125 }
126
127
128 // BoostContext
129
130 void BoostContext::smx_ctx_boost_wrapper(BoostContext::ctx_arg_type arg)
131 {
132 #if BOOST_VERSION < 106100
133   BoostContext* context = reinterpret_cast<BoostContext*>(arg);
134 #else
135   static_cast<BoostContext**>(arg.data)[0]->fc_ = arg.fctx;
136   BoostContext* context                         = static_cast<BoostContext**>(arg.data)[1];
137 #endif
138   (*context)();
139   context->stop();
140 }
141
142 inline void BoostContext::smx_ctx_boost_jump_fcontext(BoostContext* from, BoostContext* to)
143 {
144 #if BOOST_VERSION < 105600
145   boost::context::jump_fcontext(from->fc_, to->fc_, reinterpret_cast<intptr_t>(to));
146 #elif BOOST_VERSION < 106100
147   boost::context::jump_fcontext(&from->fc_, to->fc_, reinterpret_cast<intptr_t>(to));
148 #else
149   BoostContext* ctx[2]                          = {from, to};
150   boost::context::detail::transfer_t arg        = boost::context::detail::jump_fcontext(to->fc_, ctx);
151   static_cast<BoostContext**>(arg.data)[0]->fc_ = arg.fctx;
152 #endif
153 }
154
155 BoostContext::BoostContext(std::function<void()> code,
156     void_pfn_smxprocess_t cleanup_func, smx_actor_t process)
157   : Context(std::move(code), cleanup_func, process)
158 {
159
160   /* if the user provided a function for the process then use it, otherwise it is the context for maestro */
161   if (has_code()) {
162     this->stack_ = SIMIX_context_stack_new();
163 // We need to pass the bottom of the stack to make_fcontext, depending on the stack direction it may be the lower
164 // or higher address:
165 #if PTH_STACKGROWTH == -1
166     void* stack = static_cast<char*>(this->stack_) + smx_context_usable_stack_size - 1;
167 #else
168     void* stack = this->stack_;
169 #endif
170 #if BOOST_VERSION < 106100
171     this->fc_ = boost::context::make_fcontext(stack, smx_context_usable_stack_size, smx_ctx_boost_wrapper);
172 #else
173     this->fc_ = boost::context::detail::make_fcontext(stack, smx_context_usable_stack_size, smx_ctx_boost_wrapper);
174 #endif
175   } else {
176 #if BOOST_VERSION < 105600
177     this->fc_ = new boost::context::fcontext_t();
178 #endif
179     if (BoostContext::maestro_context_ == nullptr)
180       BoostContext::maestro_context_ = this;
181   }
182 }
183
184 BoostContext::~BoostContext()
185 {
186 #if BOOST_VERSION < 105600
187   if (not this->stack_)
188     delete this->fc_;
189 #endif
190   if (this == maestro_context_)
191     maestro_context_ = nullptr;
192   SIMIX_context_stack_delete(this->stack_);
193 }
194
195 // BoostSerialContext
196
197 void BoostContext::resume()
198 {
199   SIMIX_context_set_current(this);
200   smx_ctx_boost_jump_fcontext(maestro_context_, this);
201 }
202
203 void BoostSerialContext::suspend()
204 {
205   /* determine the next context */
206   BoostSerialContext* next_context;
207   unsigned long int i = process_index_;
208   process_index_++;
209
210   if (i < simix_global->process_to_run.size()) {
211     /* execute the next process */
212     XBT_DEBUG("Run next process");
213     next_context = static_cast<BoostSerialContext*>(simix_global->process_to_run[i]->context);
214   } else {
215     /* all processes were run, return to maestro */
216     XBT_DEBUG("No more process to run");
217     next_context = static_cast<BoostSerialContext*>(maestro_context_);
218   }
219   SIMIX_context_set_current(static_cast<smx_context_t>(next_context));
220   smx_ctx_boost_jump_fcontext(this, next_context);
221 }
222
223 void BoostSerialContext::stop()
224 {
225   BoostContext::stop();
226   this->suspend();
227 }
228
229 // BoostParallelContext
230
231 #if HAVE_THREAD_CONTEXTS
232
233 void BoostParallelContext::suspend()
234 {
235   boost::optional<smx_actor_t> next_work = parmap_->next();
236   BoostParallelContext* next_context;
237   if (next_work) {
238     XBT_DEBUG("Run next process");
239     next_context = static_cast<BoostParallelContext*>(next_work.get()->context);
240   } else {
241     XBT_DEBUG("No more processes to run");
242     uintptr_t worker_id = reinterpret_cast<uintptr_t>(xbt_os_thread_get_specific(worker_id_key_));
243     next_context = static_cast<BoostParallelContext*>(workers_context_[worker_id]);
244   }
245
246   SIMIX_context_set_current(static_cast<smx_context_t>(next_context));
247   smx_ctx_boost_jump_fcontext(this, next_context);
248 }
249
250 void BoostParallelContext::stop()
251 {
252   BoostContext::stop();
253   this->suspend();
254 }
255
256 void BoostParallelContext::resume()
257 {
258   uintptr_t worker_id = __sync_fetch_and_add(&threads_working_, 1);
259   xbt_os_thread_set_specific(worker_id_key_, reinterpret_cast<void*>(worker_id));
260
261   BoostParallelContext* worker_context = static_cast<BoostParallelContext*>(SIMIX_context_self());
262   workers_context_[worker_id] = worker_context;
263
264   SIMIX_context_set_current(this);
265   smx_ctx_boost_jump_fcontext(worker_context, this);
266 }
267
268 #endif
269
270 XBT_PRIVATE ContextFactory* boost_factory()
271 {
272   XBT_VERB("Using Boost contexts. Welcome to the 21th century.");
273   return new BoostContextFactory();
274 }
275
276 }}} // namespace