src/mc/mc_state.cpp

   1 /* Copyright (c) 2008-2017. 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 <assert.h>
   7
   8 #include <boost/range/algorithm.hpp>
   9
  10 #include "xbt/log.h"
  11 #include "xbt/sysdep.h"
  12
  13 #include "src/mc/Transition.hpp"
  14 #include "src/mc/mc_comm_pattern.hpp"
  15 #include "src/mc/mc_private.h"
  16 #include "src/mc/mc_request.h"
  17 #include "src/mc/mc_smx.h"
  18 #include "src/mc/mc_state.h"
  19 #include "src/mc/mc_xbt.hpp"
  20 #include "src/simix/smx_private.h"
  21
  22 using simgrid::mc::remote;
  23
  24 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_state, mc, "Logging specific to MC (state)");
  25
  26 namespace simgrid {
  27 namespace mc {
  28
  29 State::State(unsigned long state_number)
  30 {
  31   this->internal_comm.clear();
  32   std::memset(&this->internal_req, 0, sizeof(this->internal_req));
  33   std::memset(&this->executed_req, 0, sizeof(this->executed_req));
  34
  35   actorStates.resize(MC_smx_get_maxpid());
  36   num = state_number;
  37   /* Stateful model checking */
  38   if ((_sg_mc_checkpoint > 0 && (state_number % _sg_mc_checkpoint == 0)) || _sg_mc_termination) {
  39     system_state = simgrid::mc::take_snapshot(num);
  40     if (_sg_mc_comms_determinism || _sg_mc_send_determinism) {
  41       MC_state_copy_incomplete_communications_pattern(this);
  42       MC_state_copy_index_communications_pattern(this);
  43     }
  44   }
  45 }
  46
  47 std::size_t State::interleaveSize() const
  48 {
  49   return boost::range::count_if(this->actorStates,
  50     [](simgrid::mc::ProcessState const& p) { return p.isTodo(); });
  51 }
  52
  53 Transition State::getTransition() const
  54 {
  55   return this->transition;
  56 }
  57
  58 }
  59 }
  60
  61 /* Search an enabled transition for the given process.
  62  *
  63  * This can be seen as an iterator returning the next transition of the process.
  64  *
  65  * We only consider the processes that are both
  66  *  - marked "to be interleaved" in their ProcessState (controlled by the checker algorithm).
  67  *  - which simcall can currently be executed (like a comm where the other partner is already known)
  68  * Once we returned the last enabled transition of a process, it is marked done.
  69  *
  70  * Things can get muddled with the WAITANY and TESTANY simcalls, that are rewritten
  71  * on the fly to a bunch of WAIT (resp TEST) transitions using the transition.argument
  72  * field to remember what was the last returned sub-transition.
  73  */
  74 static inline smx_simcall_t MC_state_get_request_for_process(
  75   simgrid::mc::State* state, smx_actor_t actor)
  76 {
  77   /* reset the outgoing transition */
  78   simgrid::mc::ProcessState* procstate = &state->actorStates[actor->pid];
  79   state->transition.pid                = -1;
  80   state->transition.argument           = -1;
  81   state->executed_req.call             = SIMCALL_NONE;
  82
  83   if (not simgrid::mc::actor_is_enabled(actor))
  84     return nullptr; // Not executable in the application
  85
  86   smx_simcall_t req = nullptr;
  87   switch (actor->simcall.call) {
  88       case SIMCALL_COMM_WAITANY:
  89         state->transition.argument = -1;
  90         while (procstate->times_considered <
  91               read_length(mc_model_checker->process(),
  92                 remote(simcall_comm_waitany__get__comms(&actor->simcall)))) {
  93           if (simgrid::mc::request_is_enabled_by_idx(&actor->simcall,
  94               procstate->times_considered++)) {
  95             state->transition.argument = procstate->times_considered - 1;
  96             break;
  97           }
  98         }
  99
 100         if (procstate->times_considered >=
 101             simgrid::mc::read_length(mc_model_checker->process(),
 102               simgrid::mc::remote(simcall_comm_waitany__get__comms(&actor->simcall))))
 103           procstate->setDone();
 104         if (state->transition.argument != -1)
 105           req = &actor->simcall;
 106         break;
 107
 108       case SIMCALL_COMM_TESTANY: {
 109         unsigned start_count = procstate->times_considered;
 110         state->transition.argument = -1;
 111         while (procstate->times_considered <
 112                 simcall_comm_testany__get__count(&actor->simcall))
 113           if (simgrid::mc::request_is_enabled_by_idx(&actor->simcall,
 114               procstate->times_considered++)) {
 115             state->transition.argument = procstate->times_considered - 1;
 116             break;
 117           }
 118
 119         if (procstate->times_considered >=
 120             simcall_comm_testany__get__count(&actor->simcall))
 121           procstate->setDone();
 122
 123         if (state->transition.argument != -1 || start_count == 0)
 124            req = &actor->simcall;
 125
 126         break;
 127       }
 128
 129       case SIMCALL_COMM_WAIT: {
 130         simgrid::mc::RemotePtr<simgrid::kernel::activity::CommImpl> remote_act =
 131             remote(static_cast<simgrid::kernel::activity::CommImpl*>(simcall_comm_wait__getraw__comm(&actor->simcall)));
 132         simgrid::mc::Remote<simgrid::kernel::activity::CommImpl> temp_act;
 133         mc_model_checker->process().read(temp_act, remote_act);
 134         simgrid::kernel::activity::CommImpl* act = temp_act.getBuffer();
 135         if (act->src_proc && act->dst_proc)
 136           state->transition.argument = 0;
 137         else if (act->src_proc == nullptr && act->type == SIMIX_COMM_READY
 138               && act->detached == 1)
 139           state->transition.argument = 0;
 140         else
 141           state->transition.argument = -1;
 142         procstate->setDone();
 143         req = &actor->simcall;
 144         break;
 145       }
 146
 147       case SIMCALL_MC_RANDOM: {
 148         int min_value = simcall_mc_random__get__min(&actor->simcall);
 149         state->transition.argument = procstate->times_considered + min_value;
 150         procstate->times_considered++;
 151         if (state->transition.argument == simcall_mc_random__get__max(&actor->simcall))
 152           procstate->setDone();
 153         req = &actor->simcall;
 154         break;
 155       }
 156
 157       default:
 158         procstate->setDone();
 159         state->transition.argument = 0;
 160         req = &actor->simcall;
 161         break;
 162   }
 163   if (not req)
 164     return nullptr;
 165
 166   state->transition.pid = actor->pid;
 167   state->executed_req = *req;
 168   // Fetch the data of the request and translate it:
 169   state->internal_req = *req;
 170
 171   /* The waitany and testany request are transformed into a wait or test request
 172    * over the corresponding communication action so it can be treated later by
 173    * the dependence function. */
 174   switch (req->call) {
 175   case SIMCALL_COMM_WAITANY: {
 176     state->internal_req.call = SIMCALL_COMM_WAIT;
 177     simgrid::kernel::activity::ActivityImpl* remote_comm;
 178     read_element(mc_model_checker->process(), &remote_comm, remote(simcall_comm_waitany__getraw__comms(req)),
 179                  state->transition.argument, sizeof(remote_comm));
 180     mc_model_checker->process().read(state->internal_comm,
 181                                      remote(static_cast<simgrid::kernel::activity::CommImpl*>(remote_comm)));
 182     simcall_comm_wait__set__comm(&state->internal_req, state->internal_comm.getBuffer());
 183     simcall_comm_wait__set__timeout(&state->internal_req, 0);
 184     break;
 185   }
 186
 187   case SIMCALL_COMM_TESTANY:
 188     state->internal_req.call = SIMCALL_COMM_TEST;
 189
 190     if (state->transition.argument > 0) {
 191       simgrid::kernel::activity::ActivityImpl* remote_comm = mc_model_checker->process().read(
 192           remote(simcall_comm_testany__getraw__comms(req) + state->transition.argument));
 193       mc_model_checker->process().read(state->internal_comm,
 194                                        remote(static_cast<simgrid::kernel::activity::CommImpl*>(remote_comm)));
 195     }
 196
 197     simcall_comm_test__set__comm(&state->internal_req, state->internal_comm.getBuffer());
 198     simcall_comm_test__set__result(&state->internal_req, state->transition.argument);
 199     break;
 200
 201   case SIMCALL_COMM_WAIT:
 202     mc_model_checker->process().read_bytes(&state->internal_comm, sizeof(state->internal_comm),
 203                                            remote(simcall_comm_wait__getraw__comm(req)));
 204     simcall_comm_wait__set__comm(&state->executed_req, state->internal_comm.getBuffer());
 205     simcall_comm_wait__set__comm(&state->internal_req, state->internal_comm.getBuffer());
 206     break;
 207
 208   case SIMCALL_COMM_TEST:
 209     mc_model_checker->process().read_bytes(&state->internal_comm, sizeof(state->internal_comm),
 210                                            remote(simcall_comm_test__getraw__comm(req)));
 211     simcall_comm_test__set__comm(&state->executed_req, state->internal_comm.getBuffer());
 212     simcall_comm_test__set__comm(&state->internal_req, state->internal_comm.getBuffer());
 213     break;
 214
 215   default:
 216     /* No translation needed */
 217     break;
 218   }
 219
 220   return req;
 221 }
 222
 223 smx_simcall_t MC_state_get_request(simgrid::mc::State* state)
 224 {
 225   for (auto& actor : mc_model_checker->process().actors()) {
 226     /* Only consider the actors that were marked as interleaving by the checker algorithm */
 227     if (not state->actorStates[actor.copy.getBuffer()->pid].isTodo())
 228       continue;
 229
 230     smx_simcall_t res = MC_state_get_request_for_process(state, actor.copy.getBuffer());
 231     if (res)
 232       return res;
 233   }
 234   return nullptr;
 235 }