src/mc/mc_state.cpp

   1 /* Copyright (c) 2008-2019. 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 "src/mc/mc_comm_pattern.hpp"
   7 #include "src/mc/mc_request.hpp"
   8 #include "src/mc/mc_smx.hpp"
   9 #include "src/mc/mc_state.hpp"
  10 #include "src/mc/mc_xbt.hpp"
  11
  12 #include <boost/range/algorithm.hpp>
  13
  14 using simgrid::mc::remote;
  15
  16 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_state, mc, "Logging specific to MC (state)");
  17
  18 namespace simgrid {
  19 namespace mc {
  20
  21 State::State(unsigned long state_number) : num(state_number)
  22 {
  23   this->internal_comm.clear();
  24   std::memset(&this->internal_req, 0, sizeof(this->internal_req));
  25   std::memset(&this->executed_req, 0, sizeof(this->executed_req));
  26
  27   actorStates.resize(MC_smx_get_maxpid());
  28   /* Stateful model checking */
  29   if ((_sg_mc_checkpoint > 0 && (state_number % _sg_mc_checkpoint == 0)) || _sg_mc_termination) {
  30     system_state = simgrid::mc::take_snapshot(num);
  31     if (_sg_mc_comms_determinism || _sg_mc_send_determinism) {
  32       MC_state_copy_incomplete_communications_pattern(this);
  33       MC_state_copy_index_communications_pattern(this);
  34     }
  35   }
  36 }
  37
  38 std::size_t State::interleaveSize() const
  39 {
  40   return boost::range::count_if(this->actorStates, [](simgrid::mc::ProcessState const& p) { return p.isTodo(); });
  41 }
  42
  43 Transition State::getTransition() const
  44 {
  45   return this->transition;
  46 }
  47
  48 }
  49 }
  50
  51 /* Search an enabled transition for the given process.
  52  *
  53  * This can be seen as an iterator returning the next transition of the process.
  54  *
  55  * We only consider the processes that are both
  56  *  - marked "to be interleaved" in their ProcessState (controlled by the checker algorithm).
  57  *  - which simcall can currently be executed (like a comm where the other partner is already known)
  58  * Once we returned the last enabled transition of a process, it is marked done.
  59  *
  60  * Things can get muddled with the WAITANY and TESTANY simcalls, that are rewritten on the fly to a bunch of WAIT
  61  * (resp TEST) transitions using the transition.argument field to remember what was the last returned sub-transition.
  62  */
  63 static inline smx_simcall_t MC_state_get_request_for_process(simgrid::mc::State* state, smx_actor_t actor)
  64 {
  65   /* reset the outgoing transition */
  66   simgrid::mc::ProcessState* procstate = &state->actorStates[actor->pid_];
  67   state->transition.pid                = -1;
  68   state->transition.argument           = -1;
  69   state->executed_req.call             = SIMCALL_NONE;
  70
  71   if (not simgrid::mc::actor_is_enabled(actor))
  72     return nullptr; // Not executable in the application
  73
  74   smx_simcall_t req = nullptr;
  75   switch (actor->simcall.call) {
  76     case SIMCALL_COMM_WAITANY:
  77       state->transition.argument = -1;
  78       while (procstate->times_considered <
  79              read_length(mc_model_checker->process(), remote(simcall_comm_waitany__get__comms(&actor->simcall)))) {
  80         if (simgrid::mc::request_is_enabled_by_idx(&actor->simcall, procstate->times_considered++)) {
  81           state->transition.argument = procstate->times_considered - 1;
  82           break;
  83         }
  84       }
  85
  86       if (procstate->times_considered >=
  87           simgrid::mc::read_length(mc_model_checker->process(),
  88                                    simgrid::mc::remote(simcall_comm_waitany__get__comms(&actor->simcall))))
  89         procstate->setDone();
  90       if (state->transition.argument != -1)
  91         req = &actor->simcall;
  92       break;
  93
  94     case SIMCALL_COMM_TESTANY: {
  95       unsigned start_count       = procstate->times_considered;
  96       state->transition.argument = -1;
  97       while (procstate->times_considered < simcall_comm_testany__get__count(&actor->simcall))
  98         if (simgrid::mc::request_is_enabled_by_idx(&actor->simcall, procstate->times_considered++)) {
  99           state->transition.argument = procstate->times_considered - 1;
 100           break;
 101         }
 102
 103       if (procstate->times_considered >= simcall_comm_testany__get__count(&actor->simcall))
 104         procstate->setDone();
 105
 106       if (state->transition.argument != -1 || start_count == 0)
 107         req = &actor->simcall;
 108
 109       break;
 110     }
 111
 112     case SIMCALL_COMM_WAIT: {
 113       simgrid::mc::RemotePtr<simgrid::kernel::activity::CommImpl> remote_act =
 114           remote(static_cast<simgrid::kernel::activity::CommImpl*>(simcall_comm_wait__getraw__comm(&actor->simcall)));
 115       simgrid::mc::Remote<simgrid::kernel::activity::CommImpl> temp_act;
 116       mc_model_checker->process().read(temp_act, remote_act);
 117       simgrid::kernel::activity::CommImpl* act = temp_act.getBuffer();
 118       if (act->src_proc && act->dst_proc)
 119         state->transition.argument = 0;
 120       else if (act->src_proc == nullptr && act->type == SIMIX_COMM_READY && act->detached == 1)
 121         state->transition.argument = 0;
 122       else
 123         state->transition.argument = -1;
 124       procstate->setDone();
 125       req = &actor->simcall;
 126       break;
 127     }
 128
 129     case SIMCALL_MC_RANDOM: {
 130       int min_value              = simcall_mc_random__get__min(&actor->simcall);
 131       state->transition.argument = procstate->times_considered + min_value;
 132       procstate->times_considered++;
 133       if (state->transition.argument == simcall_mc_random__get__max(&actor->simcall))
 134         procstate->setDone();
 135       req = &actor->simcall;
 136       break;
 137     }
 138
 139     default:
 140       procstate->setDone();
 141       state->transition.argument = 0;
 142       req                        = &actor->simcall;
 143       break;
 144   }
 145   if (not req)
 146     return nullptr;
 147
 148   state->transition.pid = actor->pid_;
 149   state->executed_req = *req;
 150   // Fetch the data of the request and translate it:
 151   state->internal_req = *req;
 152
 153   /* The waitany and testany request are transformed into a wait or test request over the corresponding communication
 154    * action so it can be treated later by the dependence function. */
 155   switch (req->call) {
 156   case SIMCALL_COMM_WAITANY: {
 157     state->internal_req.call = SIMCALL_COMM_WAIT;
 158     simgrid::kernel::activity::ActivityImpl* remote_comm;
 159     read_element(mc_model_checker->process(), &remote_comm, remote(simcall_comm_waitany__getraw__comms(req)),
 160                  state->transition.argument, sizeof(remote_comm));
 161     mc_model_checker->process().read(state->internal_comm,
 162                                      remote(static_cast<simgrid::kernel::activity::CommImpl*>(remote_comm)));
 163     simcall_comm_wait__set__comm(&state->internal_req, state->internal_comm.getBuffer());
 164     simcall_comm_wait__set__timeout(&state->internal_req, 0);
 165     break;
 166   }
 167
 168   case SIMCALL_COMM_TESTANY:
 169     state->internal_req.call = SIMCALL_COMM_TEST;
 170
 171     if (state->transition.argument > 0) {
 172       simgrid::kernel::activity::ActivityImpl* remote_comm = mc_model_checker->process().read(
 173           remote(simcall_comm_testany__getraw__comms(req) + state->transition.argument));
 174       mc_model_checker->process().read(state->internal_comm,
 175                                        remote(static_cast<simgrid::kernel::activity::CommImpl*>(remote_comm)));
 176     }
 177
 178     simcall_comm_test__set__comm(&state->internal_req, state->internal_comm.getBuffer());
 179     simcall_comm_test__set__result(&state->internal_req, state->transition.argument);
 180     break;
 181
 182   case SIMCALL_COMM_WAIT:
 183     mc_model_checker->process().read_bytes(&state->internal_comm, sizeof(state->internal_comm),
 184                                            remote(simcall_comm_wait__getraw__comm(req)));
 185     simcall_comm_wait__set__comm(&state->executed_req, state->internal_comm.getBuffer());
 186     simcall_comm_wait__set__comm(&state->internal_req, state->internal_comm.getBuffer());
 187     break;
 188
 189   case SIMCALL_COMM_TEST:
 190     mc_model_checker->process().read_bytes(&state->internal_comm, sizeof(state->internal_comm),
 191                                            remote(simcall_comm_test__getraw__comm(req)));
 192     simcall_comm_test__set__comm(&state->executed_req, state->internal_comm.getBuffer());
 193     simcall_comm_test__set__comm(&state->internal_req, state->internal_comm.getBuffer());
 194     break;
 195
 196   default:
 197     /* No translation needed */
 198     break;
 199   }
 200
 201   return req;
 202 }
 203
 204 smx_simcall_t MC_state_get_request(simgrid::mc::State* state)
 205 {
 206   for (auto& actor : mc_model_checker->process().actors()) {
 207     /* Only consider the actors that were marked as interleaving by the checker algorithm */
 208     if (not state->actorStates[actor.copy.getBuffer()->pid_].isTodo())
 209       continue;
 210
 211     smx_simcall_t res = MC_state_get_request_for_process(state, actor.copy.getBuffer());
 212     if (res)
 213       return res;
 214   }
 215   return nullptr;
 216 }