1 /* Copyright (c) 2007-2018. The SimGrid Team. All rights reserved. */
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. */
6 #include "SmpiHost.hpp"
9 #include "simgrid/s4u/Host.hpp"
10 #include "simgrid/s4u/Mailbox.hpp"
11 #include "smpi_coll.hpp"
12 #include "smpi_comm.hpp"
13 #include "smpi_group.hpp"
14 #include "smpi_info.hpp"
15 #include "smpi_process.hpp"
16 #include "src/msg/msg_private.hpp"
17 #include "src/simix/smx_private.hpp"
18 #include "src/surf/surf_interface.hpp"
19 #include "xbt/config.hpp"
21 #include <cfloat> /* DBL_MAX */
28 #include <sys/sendfile.h>
31 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(smpi_kernel, smpi, "Logging specific to SMPI (kernel)");
32 #include <boost/tokenizer.hpp>
33 #include <boost/algorithm/string.hpp> /* trim_right / trim_left */
36 /* RTLD_DEEPBIND is a bad idea of GNU ld that obviously does not exist on other platforms
37 * See https://www.akkadia.org/drepper/dsohowto.pdf
38 * and https://lists.freebsd.org/pipermail/freebsd-current/2016-March/060284.html
40 #define RTLD_DEEPBIND 0
45 const char* papi_default_config_name = "default";
47 struct papi_process_data {
48 papi_counter_t counter_data;
53 std::unordered_map<std::string, double> location2speedup;
55 static simgrid::smpi::Process** process_data = nullptr;
56 int process_count = 0;
57 int smpi_universe_size = 0;
58 int* index_to_process_data = nullptr;
59 extern double smpi_total_benched_time;
60 xbt_os_timer_t global_timer;
62 * Setting MPI_COMM_WORLD to MPI_COMM_UNINITIALIZED (it's a variable)
63 * is important because the implementation of MPI_Comm checks
64 * "this == MPI_COMM_UNINITIALIZED"? If yes, it uses smpi_process()->comm_world()
66 * This is basically how we only have one global variable but all processes have
67 * different communicators (basically, the one their SMPI instance uses).
69 * See smpi_comm.cpp and the functions therein for details.
71 MPI_Comm MPI_COMM_WORLD = MPI_COMM_UNINITIALIZED;
72 MPI_Errhandler *MPI_ERRORS_RETURN = nullptr;
73 MPI_Errhandler *MPI_ERRORS_ARE_FATAL = nullptr;
74 MPI_Errhandler *MPI_ERRHANDLER_NULL = nullptr;
75 // No instance gets manually created; check also the smpirun.in script as
76 // this default name is used there as well (when the <actor> tag is generated).
77 static const char* smpi_default_instance_name = "smpirun";
78 static simgrid::config::Flag<double> smpi_wtime_sleep(
79 "smpi/wtime", "Minimum time to inject inside a call to MPI_Wtime", 0.0);
80 static simgrid::config::Flag<double> smpi_init_sleep(
81 "smpi/init", "Time to inject inside a call to MPI_Init", 0.0);
83 void (*smpi_comm_copy_data_callback) (smx_activity_t, void*, size_t) = &smpi_comm_copy_buffer_callback;
85 int smpi_process_count()
90 simgrid::smpi::Process* smpi_process()
92 smx_actor_t me = SIMIX_process_self();
93 if (me == nullptr) // This happens sometimes (eg, when linking against NS3 because it pulls openMPI...)
95 simgrid::msg::ActorExt* msgExt = static_cast<simgrid::msg::ActorExt*>(me->userdata);
96 return static_cast<simgrid::smpi::Process*>(msgExt->data);
99 simgrid::smpi::Process* smpi_process_remote(int index)
101 return process_data[index_to_process_data[index]];
104 MPI_Comm smpi_process_comm_self(){
105 return smpi_process()->comm_self();
108 void smpi_process_init(int *argc, char ***argv){
109 simgrid::smpi::Process::init(argc, argv);
112 int smpi_process_index(){
113 return smpi_process()->index();
116 void * smpi_process_get_user_data(){
117 return smpi_process()->get_user_data();
120 void smpi_process_set_user_data(void *data){
121 return smpi_process()->set_user_data(data);
125 int smpi_global_size()
127 char *value = getenv("SMPI_GLOBAL_SIZE");
128 xbt_assert(value,"Please set env var SMPI_GLOBAL_SIZE to the expected number of processes.");
130 return xbt_str_parse_int(value, "SMPI_GLOBAL_SIZE contains a non-numerical value: %s");
133 void smpi_comm_set_copy_data_callback(void (*callback) (smx_activity_t, void*, size_t))
135 smpi_comm_copy_data_callback = callback;
138 static void print(std::vector<std::pair<size_t, size_t>> vec) {
139 std::fprintf(stderr, "{");
140 for (auto const& elt : vec) {
141 std::fprintf(stderr, "(0x%zx, 0x%zx),", elt.first, elt.second);
143 std::fprintf(stderr, "}\n");
145 static void memcpy_private(void* dest, const void* src, std::vector<std::pair<size_t, size_t>>& private_blocks)
147 for (auto const& block : private_blocks)
148 memcpy((uint8_t*)dest+block.first, (uint8_t*)src+block.first, block.second-block.first);
151 static void check_blocks(std::vector<std::pair<size_t, size_t>> &private_blocks, size_t buff_size) {
152 for (auto const& block : private_blocks)
153 xbt_assert(block.first <= block.second && block.second <= buff_size, "Oops, bug in shared malloc.");
156 void smpi_comm_copy_buffer_callback(smx_activity_t synchro, void *buff, size_t buff_size)
158 simgrid::kernel::activity::CommImplPtr comm =
159 boost::dynamic_pointer_cast<simgrid::kernel::activity::CommImpl>(synchro);
162 size_t src_offset = 0;
163 size_t dst_offset = 0;
164 std::vector<std::pair<size_t, size_t>> src_private_blocks;
165 std::vector<std::pair<size_t, size_t>> dst_private_blocks;
166 XBT_DEBUG("Copy the data over");
167 if((src_shared=smpi_is_shared(buff, src_private_blocks, &src_offset))) {
168 XBT_DEBUG("Sender %p is shared. Let's ignore it.", buff);
169 src_private_blocks = shift_and_frame_private_blocks(src_private_blocks, src_offset, buff_size);
172 src_private_blocks.clear();
173 src_private_blocks.push_back(std::make_pair(0, buff_size));
175 if((dst_shared=smpi_is_shared((char*)comm->dst_buff, dst_private_blocks, &dst_offset))) {
176 XBT_DEBUG("Receiver %p is shared. Let's ignore it.", (char*)comm->dst_buff);
177 dst_private_blocks = shift_and_frame_private_blocks(dst_private_blocks, dst_offset, buff_size);
180 dst_private_blocks.clear();
181 dst_private_blocks.push_back(std::make_pair(0, buff_size));
183 check_blocks(src_private_blocks, buff_size);
184 check_blocks(dst_private_blocks, buff_size);
185 auto private_blocks = merge_private_blocks(src_private_blocks, dst_private_blocks);
186 check_blocks(private_blocks, buff_size);
188 if ((smpi_privatize_global_variables == SMPI_PRIVATIZE_MMAP) && (static_cast<char*>(buff) >= smpi_data_exe_start) &&
189 (static_cast<char*>(buff) < smpi_data_exe_start + smpi_data_exe_size)) {
190 XBT_DEBUG("Privatization : We are copying from a zone inside global memory... Saving data to temp buffer !");
192 smpi_switch_data_segment(
193 static_cast<simgrid::smpi::Process*>((static_cast<simgrid::msg::ActorExt*>(comm->src_proc->userdata)->data))
195 tmpbuff = static_cast<void*>(xbt_malloc(buff_size));
196 memcpy_private(tmpbuff, buff, private_blocks);
199 if ((smpi_privatize_global_variables == SMPI_PRIVATIZE_MMAP) && ((char*)comm->dst_buff >= smpi_data_exe_start) &&
200 ((char*)comm->dst_buff < smpi_data_exe_start + smpi_data_exe_size)) {
201 XBT_DEBUG("Privatization : We are copying to a zone inside global memory - Switch data segment");
202 smpi_switch_data_segment(
203 static_cast<simgrid::smpi::Process*>((static_cast<simgrid::msg::ActorExt*>(comm->dst_proc->userdata)->data))
206 XBT_DEBUG("Copying %zu bytes from %p to %p", buff_size, tmpbuff,comm->dst_buff);
207 memcpy_private(comm->dst_buff, tmpbuff, private_blocks);
209 if (comm->detached) {
210 // if this is a detached send, the source buffer was duplicated by SMPI
211 // sender to make the original buffer available to the application ASAP
213 //It seems that the request is used after the call there this should be free somewhere else but where???
214 //xbt_free(comm->comm.src_data);// inside SMPI the request is kept inside the user data and should be free
215 comm->src_buff = nullptr;
221 void smpi_comm_null_copy_buffer_callback(smx_activity_t comm, void *buff, size_t buff_size)
223 /* nothing done in this version */
226 static void smpi_check_options(){
227 //check correctness of MPI parameters
229 xbt_assert(xbt_cfg_get_int("smpi/async-small-thresh") <= xbt_cfg_get_int("smpi/send-is-detached-thresh"));
231 if (xbt_cfg_is_default_value("smpi/host-speed")) {
232 XBT_INFO("You did not set the power of the host running the simulation. "
233 "The timings will certainly not be accurate. "
234 "Use the option \"--cfg=smpi/host-speed:<flops>\" to set its value."
235 "Check http://simgrid.org/simgrid/latest/doc/options.html#options_smpi_bench for more information.");
238 xbt_assert(xbt_cfg_get_double("smpi/cpu-threshold") >=0,
239 "The 'smpi/cpu-threshold' option cannot have negative values [anymore]. If you want to discard "
240 "the simulation of any computation, please use 'smpi/simulate-computation:no' instead.");
244 return process_data != nullptr;
247 void smpi_global_init()
249 if (not MC_is_active()) {
250 global_timer = xbt_os_timer_new();
251 xbt_os_walltimer_start(global_timer);
254 std::string filename = xbt_cfg_get_string("smpi/comp-adjustment-file");
255 if (not filename.empty()) {
256 std::ifstream fstream(filename);
257 if (not fstream.is_open()) {
258 xbt_die("Could not open file %s. Does it exist?", filename.c_str());
262 typedef boost::tokenizer< boost::escaped_list_separator<char>> Tokenizer;
263 std::getline(fstream, line); // Skip the header line
264 while (std::getline(fstream, line)) {
266 Tokenizer::iterator it = tok.begin();
267 Tokenizer::iterator end = std::next(tok.begin());
269 std::string location = *it;
270 boost::trim(location);
271 location2speedup.insert(std::pair<std::string, double>(location, std::stod(*end)));
276 // This map holds for each computation unit (such as "default" or "process1" etc.)
277 // the configuration as given by the user (counter data as a pair of (counter_name, counter_counter))
278 // and the (computed) event_set.
279 std::map</* computation unit name */ std::string, papi_process_data> units2papi_setup;
281 if (not xbt_cfg_get_string("smpi/papi-events").empty()) {
282 if (PAPI_library_init(PAPI_VER_CURRENT) != PAPI_VER_CURRENT)
283 XBT_ERROR("Could not initialize PAPI library; is it correctly installed and linked?"
284 " Expected version is %i",
287 typedef boost::tokenizer<boost::char_separator<char>> Tokenizer;
288 boost::char_separator<char> separator_units(";");
289 std::string str = xbt_cfg_get_string("smpi/papi-events");
290 Tokenizer tokens(str, separator_units);
292 // Iterate over all the computational units. This could be processes, hosts, threads, ranks... You name it.
293 // I'm not exactly sure what we will support eventually, so I'll leave it at the general term "units".
294 for (auto const& unit_it : tokens) {
295 boost::char_separator<char> separator_events(":");
296 Tokenizer event_tokens(unit_it, separator_events);
298 int event_set = PAPI_NULL;
299 if (PAPI_create_eventset(&event_set) != PAPI_OK) {
300 // TODO: Should this let the whole simulation die?
301 XBT_CRITICAL("Could not create PAPI event set during init.");
304 // NOTE: We cannot use a map here, as we must obey the order of the counters
305 // This is important for PAPI: We need to map the values of counters back
306 // to the event_names (so, when PAPI_read() has finished)!
307 papi_counter_t counters2values;
309 // Iterate over all counters that were specified for this specific
311 // Note that we need to remove the name of the unit
312 // (that could also be the "default" value), which always comes first.
313 // Hence, we start at ++(events.begin())!
314 for (Tokenizer::iterator events_it = ++(event_tokens.begin()); events_it != event_tokens.end(); ++events_it) {
316 int event_code = PAPI_NULL;
317 char* event_name = const_cast<char*>((*events_it).c_str());
318 if (PAPI_event_name_to_code(event_name, &event_code) == PAPI_OK) {
319 if (PAPI_add_event(event_set, event_code) != PAPI_OK) {
320 XBT_ERROR("Could not add PAPI event '%s'. Skipping.", event_name);
323 XBT_DEBUG("Successfully added PAPI event '%s' to the event set.", event_name);
326 XBT_CRITICAL("Could not find PAPI event '%s'. Skipping.", event_name);
330 counters2values.push_back(
331 // We cannot just pass *events_it, as this is of type const basic_string
332 std::make_pair<std::string, long long>(std::string(*events_it), 0));
335 std::string unit_name = *(event_tokens.begin());
336 papi_process_data config = {.counter_data = std::move(counters2values), .event_set = event_set};
338 units2papi_setup.insert(std::make_pair(unit_name, std::move(config)));
343 if (index_to_process_data == nullptr) {
344 index_to_process_data = new int[SIMIX_process_count()];
348 if (process_count == 0) { // The program has been dispatched but no other
349 // SMPI instances have been registered. We're using smpirun.
351 SMPI_app_instance_register(smpi_default_instance_name, nullptr,
352 SIMIX_process_count()); // This call has a side effect on process_count...
353 MPI_COMM_WORLD = *smpi_deployment_comm_world(smpi_default_instance_name);
355 smpi_universe_size = process_count;
356 process_data = new simgrid::smpi::Process*[process_count];
357 for (int i = 0; i < process_count; i++) {
359 process_data[i] = new simgrid::smpi::Process(i, smpi_deployment_finalization_barrier(smpi_default_instance_name));
360 smpi_deployment_register_process(smpi_default_instance_name, i, i);
362 // TODO We can pass a nullptr here because Process::set_data() assigns the
363 // barrier from the instance anyway. This is ugly and should be changed
364 process_data[i] = new simgrid::smpi::Process(i, nullptr);
369 void smpi_global_destroy()
371 smpi_bench_destroy();
372 smpi_shared_destroy();
373 smpi_deployment_cleanup_instances();
374 int count = smpi_process_count();
375 for (int i = 0; i < count; i++) {
376 if(process_data[i]->comm_self()!=MPI_COMM_NULL){
377 simgrid::smpi::Comm::destroy(process_data[i]->comm_self());
379 if(process_data[i]->comm_intra()!=MPI_COMM_NULL){
380 simgrid::smpi::Comm::destroy(process_data[i]->comm_intra());
382 xbt_os_timer_free(process_data[i]->timer());
383 xbt_mutex_destroy(process_data[i]->mailboxes_mutex());
384 delete process_data[i];
386 delete[] process_data;
387 process_data = nullptr;
389 if (simgrid::smpi::Colls::smpi_coll_cleanup_callback != nullptr)
390 simgrid::smpi::Colls::smpi_coll_cleanup_callback();
392 MPI_COMM_WORLD = MPI_COMM_NULL;
394 if (not MC_is_active()) {
395 xbt_os_timer_free(global_timer);
398 delete[] index_to_process_data;
399 if(smpi_privatize_global_variables == SMPI_PRIVATIZE_MMAP)
400 smpi_destroy_global_memory_segments();
404 static void smpi_init_options(){
405 // return if already called
406 if (smpi_cpu_threshold > -1)
408 simgrid::smpi::Colls::set_collectives();
409 simgrid::smpi::Colls::smpi_coll_cleanup_callback = nullptr;
410 smpi_cpu_threshold = xbt_cfg_get_double("smpi/cpu-threshold");
411 smpi_host_speed = xbt_cfg_get_double("smpi/host-speed");
412 std::string smpi_privatize_option = xbt_cfg_get_string("smpi/privatization");
413 if (smpi_privatize_option == "no" || smpi_privatize_option == "0")
414 smpi_privatize_global_variables = SMPI_PRIVATIZE_NONE;
415 else if (smpi_privatize_option == "yes" || smpi_privatize_option == "1")
416 smpi_privatize_global_variables = SMPI_PRIVATIZE_DEFAULT;
417 else if (smpi_privatize_option == "mmap")
418 smpi_privatize_global_variables = SMPI_PRIVATIZE_MMAP;
419 else if (smpi_privatize_option == "dlopen")
420 smpi_privatize_global_variables = SMPI_PRIVATIZE_DLOPEN;
422 xbt_die("Invalid value for smpi/privatization: '%s'", smpi_privatize_option.c_str());
424 #if defined(__FreeBSD__)
425 if (smpi_privatize_global_variables == SMPI_PRIVATIZE_MMAP) {
426 XBT_INFO("Mixing mmap privatization is broken on FreeBSD, switching to dlopen privatization instead.");
427 smpi_privatize_global_variables = SMPI_PRIVATIZE_DLOPEN;
431 if (smpi_cpu_threshold < 0)
432 smpi_cpu_threshold = DBL_MAX;
434 std::string val = xbt_cfg_get_string("smpi/shared-malloc");
435 if ((val == "yes") || (val == "1") || (val == "on") || (val == "global")) {
436 smpi_cfg_shared_malloc = shmalloc_global;
437 } else if (val == "local") {
438 smpi_cfg_shared_malloc = shmalloc_local;
439 } else if ((val == "no") || (val == "0") || (val == "off")) {
440 smpi_cfg_shared_malloc = shmalloc_none;
442 xbt_die("Invalid value '%s' for option smpi/shared-malloc. Possible values: 'on' or 'global', 'local', 'off'",
447 typedef std::function<int(int argc, char *argv[])> smpi_entry_point_type;
448 typedef int (* smpi_c_entry_point_type)(int argc, char **argv);
449 typedef void (*smpi_fortran_entry_point_type)();
451 static int smpi_run_entry_point(smpi_entry_point_type entry_point, std::vector<std::string> args)
453 char noarg[] = {'\0'};
454 const int argc = args.size();
455 std::unique_ptr<char*[]> argv(new char*[argc + 1]);
456 for (int i = 0; i != argc; ++i)
457 argv[i] = args[i].empty() ? noarg : &args[i].front();
458 argv[argc] = nullptr;
460 int res = entry_point(argc, argv.get());
462 XBT_WARN("SMPI process did not return 0. Return value : %d", res);
463 smpi_process()->set_return_value(res);
468 // TODO, remove the number of functions involved here
469 static smpi_entry_point_type smpi_resolve_function(void* handle)
471 smpi_fortran_entry_point_type entry_point_fortran = (smpi_fortran_entry_point_type)dlsym(handle, "user_main_");
472 if (entry_point_fortran != nullptr) {
473 return [entry_point_fortran](int argc, char** argv) {
474 smpi_process_init(&argc, &argv);
475 entry_point_fortran();
480 smpi_c_entry_point_type entry_point = (smpi_c_entry_point_type)dlsym(handle, "main");
481 if (entry_point != nullptr) {
485 return smpi_entry_point_type();
488 int smpi_main(const char* executable, int argc, char *argv[])
490 srand(SMPI_RAND_SEED);
492 if (getenv("SMPI_PRETEND_CC") != nullptr) {
493 /* Hack to ensure that smpicc can pretend to be a simple compiler. Particularly handy to pass it to the
494 * configuration tools */
500 SIMIX_global_init(&argc, argv);
501 MSG_init(&argc,argv);
503 SMPI_switch_data_segment = &smpi_switch_data_segment;
505 simgrid::s4u::Host::onCreation.connect([](simgrid::s4u::Host& host) {
506 host.extension_set(new simgrid::smpi::SmpiHost(&host));
509 // parse the platform file: get the host list
510 SIMIX_create_environment(argv[1]);
511 SIMIX_comm_set_copy_data_callback(smpi_comm_copy_buffer_callback);
515 if (smpi_privatize_global_variables == SMPI_PRIVATIZE_DLOPEN) {
517 std::string executable_copy = executable;
519 // Prepare the copy of the binary (get its size)
520 struct stat fdin_stat;
521 stat(executable_copy.c_str(), &fdin_stat);
522 off_t fdin_size = fdin_stat.st_size;
523 static std::size_t rank = 0;
525 simix_global->default_function = [executable_copy, fdin_size](std::vector<std::string> args) {
526 return std::function<void()>([executable_copy, fdin_size, args] {
528 // Copy the dynamic library:
529 std::string target_executable = executable_copy
530 + "_" + std::to_string(getpid())
531 + "_" + std::to_string(rank++) + ".so";
533 int fdin = open(executable_copy.c_str(), O_RDONLY);
534 xbt_assert(fdin >= 0, "Cannot read from %s", executable_copy.c_str());
535 int fdout = open(target_executable.c_str(), O_CREAT | O_RDWR, S_IRWXU);
536 xbt_assert(fdout >= 0, "Cannot write into %s", target_executable.c_str());
539 ssize_t sent_size = sendfile(fdout, fdin, NULL, fdin_size);
540 xbt_assert(sent_size == fdin_size,
541 "Error while copying %s: only %zd bytes copied instead of %ld (errno: %d -- %s)",
542 target_executable.c_str(), sent_size, fdin_size, errno, strerror(errno));
544 XBT_VERB("Copy %d bytes into %s", static_cast<int>(fdin_size), target_executable.c_str());
545 const int bufsize = 1024 * 1024 * 4;
547 while (int got = read(fdin, buf, bufsize)) {
549 xbt_assert(errno == EINTR, "Cannot read from %s", executable_copy.c_str());
553 while (int done = write(fdout, p, todo)) {
555 xbt_assert(errno == EINTR, "Cannot write into %s", target_executable.c_str());
567 // Load the copy and resolve the entry point:
568 void* handle = dlopen(target_executable.c_str(), RTLD_LAZY | RTLD_LOCAL | RTLD_DEEPBIND);
569 int saved_errno = errno;
570 if (xbt_cfg_get_boolean("smpi/keep-temps") == false)
571 unlink(target_executable.c_str());
572 if (handle == nullptr)
573 xbt_die("dlopen failed: %s (errno: %d -- %s)", dlerror(), saved_errno, strerror(saved_errno));
574 smpi_entry_point_type entry_point = smpi_resolve_function(handle);
576 xbt_die("Could not resolve entry point");
578 smpi_run_entry_point(entry_point, args);
585 // Load the dynamic library and resolve the entry point:
586 void* handle = dlopen(executable, RTLD_LAZY | RTLD_LOCAL | RTLD_DEEPBIND);
587 if (handle == nullptr)
588 xbt_die("dlopen failed for %s: %s (errno: %d -- %s)", executable, dlerror(), errno, strerror(errno));
589 smpi_entry_point_type entry_point = smpi_resolve_function(handle);
591 xbt_die("main not found in %s", executable);
592 // TODO, register the executable for SMPI privatization
594 // Execute the same entry point for each simulated process:
595 simix_global->default_function = [entry_point](std::vector<std::string> args) {
596 return std::function<void()>([entry_point, args] {
597 smpi_run_entry_point(entry_point, args);
603 SIMIX_launch_application(argv[2]);
607 /* Clean IO before the run */
611 if (MC_is_active()) {
617 xbt_os_walltimer_stop(global_timer);
618 if (xbt_cfg_get_boolean("smpi/display-timing")){
619 double global_time = xbt_os_timer_elapsed(global_timer);
620 XBT_INFO("Simulated time: %g seconds. \n\n"
621 "The simulation took %g seconds (after parsing and platform setup)\n"
622 "%g seconds were actual computation of the application",
623 SIMIX_get_clock(), global_time , smpi_total_benched_time);
625 if (smpi_total_benched_time/global_time>=0.75)
626 XBT_INFO("More than 75%% of the time was spent inside the application code.\n"
627 "You may want to use sampling functions or trace replay to reduce this.");
631 int count = smpi_process_count();
632 for (int i = 0; i < count; i++) {
633 if(process_data[i]->return_value()!=0){
634 ret=process_data[i]->return_value();//return first non 0 value
638 smpi_global_destroy();
645 // Called either directly from the user code, or from the code called by smpirun
649 smpi_check_options();
651 simgrid::surf::surfExitCallbacks.connect(TRACE_smpi_release);
652 if(smpi_privatize_global_variables == SMPI_PRIVATIZE_MMAP)
653 smpi_backup_global_memory_segment();
656 void SMPI_finalize(){
657 smpi_global_destroy();
660 void smpi_mpi_init() {
661 if(smpi_init_sleep > 0)
662 simcall_process_sleep(smpi_init_sleep);
665 double smpi_mpi_wtime(){
667 if (smpi_process()->initialized() != 0 && smpi_process()->finalized() == 0 && smpi_process()->sampling() == 0) {
669 time = SIMIX_get_clock();
670 // to avoid deadlocks if used as a break condition, such as
671 // while (MPI_Wtime(...) < time_limit) {
674 // because the time will not normally advance when only calls to MPI_Wtime
675 // are made -> deadlock (MPI_Wtime never reaches the time limit)
676 if(smpi_wtime_sleep > 0)
677 simcall_process_sleep(smpi_wtime_sleep);
680 time = SIMIX_get_clock();