1 /* Copyright (c) 2008-2017. 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 <simgrid_config.h>
9 #include "src/mc/mc_base.h"
10 #include "src/mc/mc_replay.h"
11 #include "src/simix/smx_private.h"
14 #include "src/mc/ModelChecker.hpp"
16 using simgrid::mc::remote;
19 XBT_LOG_NEW_DEFAULT_CATEGORY(mc, "All MC categories");
21 int MC_random(int min, int max)
24 xbt_assert(mc_model_checker == nullptr);
26 /* TODO, if the MC is disabled we do not really need to make a simcall for this :) */
27 return simcall_mc_random(min, max);
33 void wait_for_requests()
36 xbt_assert(mc_model_checker == nullptr, "This must be called from the client");
38 while (not simix_global->process_to_run.empty()) {
39 SIMIX_process_runall();
40 for (smx_actor_t const& process : simix_global->process_that_ran) {
41 smx_simcall_t req = &process->simcall;
42 if (req->call != SIMCALL_NONE && not simgrid::mc::request_is_visible(req))
43 SIMIX_simcall_handle(req, 0);
47 xbt_dynar_reset(simix_global->actors_vector);
48 for (std::pair<aid_t, smx_actor_t> const& kv : simix_global->process_list) {
49 xbt_dynar_push_as(simix_global->actors_vector, smx_actor_t, kv.second);
54 /** @brief returns if there this transition can proceed in a finite amount of time
56 * It is used in the model-checker to not get into self-deadlock where it would execute a never ending transition.
58 * Only WAIT operations (on comm, on mutex, etc) can ever return false because they could lock the MC exploration.
59 * Wait operations are OK and return true in only two situations:
60 * - if the wait will succeed immediately (if both peer of the comm are there already or if the mutex is available)
61 * - if a timeout is provided, because we can fire the timeout if the transition is not ready without blocking in this
62 * transition for ever.
65 // Called from both MCer and MCed:
66 bool actor_is_enabled(smx_actor_t actor)
69 // If in the MCer, ask the client app since it has all the data
70 if (mc_model_checker != nullptr) {
71 return mc_model_checker->process().actor_is_enabled(actor->pid);
75 // Now, we are in the client app, no need for remote memory reading.
76 smx_simcall_t req = &actor->simcall;
82 case SIMCALL_COMM_WAIT: {
83 /* FIXME: check also that src and dst processes are not suspended */
84 simgrid::kernel::activity::CommImpl* act =
85 static_cast<simgrid::kernel::activity::CommImpl*>(simcall_comm_wait__getraw__comm(req));
87 if (act->src_timeout || act->dst_timeout) {
88 /* If it has a timeout it will be always be enabled (regardless of who declared the timeout),
89 * because even if the communication is not ready, it can timeout and won't block. */
90 if (_sg_mc_timeout == 1)
93 /* On the other hand if it hasn't a timeout, check if the comm is ready.*/
94 else if (act->detached && act->src_proc == nullptr && act->type == SIMIX_COMM_READY)
95 return (act->dst_proc != nullptr);
96 return (act->src_proc && act->dst_proc);
99 case SIMCALL_COMM_WAITANY: {
100 xbt_dynar_t comms = simcall_comm_waitany__get__comms(req);
101 for (unsigned int index = 0; index < comms->used; ++index) {
102 simgrid::kernel::activity::CommImpl* act = xbt_dynar_get_as(comms, index, simgrid::kernel::activity::CommImpl*);
103 if (act->src_proc && act->dst_proc)
109 case SIMCALL_MUTEX_LOCK: {
110 smx_mutex_t mutex = simcall_mutex_lock__get__mutex(req);
112 if (mutex->owner == nullptr)
115 return mutex->owner->pid == req->issuer->pid;
118 case SIMCALL_SEM_ACQUIRE: {
119 static int warned = 0;
121 XBT_INFO("Using semaphore in model-checked code is still experimental. Use at your own risk");
126 case SIMCALL_COND_WAIT: {
127 static int warned = 0;
129 XBT_INFO("Using condition variables in model-checked code is still experimental. Use at your own risk");
135 /* The rest of the requests are always enabled */
140 /* This is the list of requests that are visible from the checker algorithm.
141 * Any other requests are handled right away on the application side.
143 bool request_is_visible(smx_simcall_t req)
146 xbt_assert(mc_model_checker == nullptr, "This should be called from the client side");
149 return req->call == SIMCALL_COMM_ISEND || req->call == SIMCALL_COMM_IRECV || req->call == SIMCALL_COMM_WAIT ||
150 req->call == SIMCALL_COMM_WAITANY || req->call == SIMCALL_COMM_TEST || req->call == SIMCALL_COMM_TESTANY ||
151 req->call == SIMCALL_MC_RANDOM || req->call == SIMCALL_MUTEX_LOCK || req->call == SIMCALL_MUTEX_TRYLOCK ||
152 req->call == SIMCALL_MUTEX_UNLOCK;
158 static int prng_random(int min, int max)
160 unsigned long output_size = ((unsigned long) max - (unsigned long) min) + 1;
161 unsigned long input_size = (unsigned long) RAND_MAX + 1;
162 unsigned long reject_size = input_size % output_size;
163 unsigned long accept_size = input_size - reject_size; // module*accept_size
165 // Use rejection in order to avoid skew
169 x = (unsigned long) random();
171 x = (unsigned long) rand();
173 } while( x >= accept_size );
174 return min + (x % output_size);
177 int simcall_HANDLER_mc_random(smx_simcall_t simcall, int min, int max)
179 if (not MC_is_active() && not MC_record_path)
180 return prng_random(min, max);
181 return simcall->mc_value;