2 #define __STDC_FORMAT_MACROS
8 #include "clockvector.h"
11 #include "nodestack.h"
13 #define ACTION_INITIAL_CLOCK 0
16 * @brief Construct a new ModelAction
18 * @param type The type of action
19 * @param order The memory order of this action. A "don't care" for non-ATOMIC
20 * actions (e.g., THREAD_* or MODEL_* actions).
21 * @param loc The location that this action acts upon
22 * @param value (optional) A value associated with the action (e.g., the value
23 * read or written). Defaults to a given macro constant, for debugging purposes.
24 * @param thread (optional) The Thread in which this action occurred. If NULL
25 * (default), then a Thread is assigned according to the scheduler.
27 ModelAction::ModelAction(action_type_t type, memory_order order, void *loc,
28 uint64_t value, Thread *thread) :
35 seq_number(ACTION_INITIAL_CLOCK),
38 Thread *t = thread ? thread : thread_current();
39 this->tid = t->get_id();
42 /** @brief ModelAction destructor */
43 ModelAction::~ModelAction()
46 * We can't free the clock vector:
47 * Clock vectors are snapshotting state. When we delete model actions,
48 * they are at the end of the node list and have invalid old clock
49 * vectors which have already been rolled back to an unallocated state.
57 void ModelAction::copy_from_new(ModelAction *newaction)
59 seq_number = newaction->seq_number;
62 void ModelAction::set_seq_number(modelclock_t num)
64 ASSERT(seq_number == ACTION_INITIAL_CLOCK);
68 bool ModelAction::is_relseq_fixup() const
70 return type == MODEL_FIXUP_RELSEQ;
73 bool ModelAction::is_mutex_op() const
75 return type == ATOMIC_LOCK || type == ATOMIC_TRYLOCK || type == ATOMIC_UNLOCK;
78 bool ModelAction::is_lock() const
80 return type == ATOMIC_LOCK;
83 bool ModelAction::is_unlock() const
85 return type == ATOMIC_UNLOCK;
88 bool ModelAction::is_trylock() const
90 return type == ATOMIC_TRYLOCK;
93 bool ModelAction::is_success_lock() const
95 return type == ATOMIC_LOCK || (type == ATOMIC_TRYLOCK && value == VALUE_TRYSUCCESS);
98 bool ModelAction::is_failed_trylock() const
100 return (type == ATOMIC_TRYLOCK && value == VALUE_TRYFAILED);
103 bool ModelAction::is_read() const
105 return type == ATOMIC_READ || type == ATOMIC_RMWR || type == ATOMIC_RMW;
108 bool ModelAction::is_write() const
110 return type == ATOMIC_WRITE || type == ATOMIC_RMW || type == ATOMIC_INIT;
113 bool ModelAction::is_rmwr() const
115 return type == ATOMIC_RMWR;
118 bool ModelAction::is_rmw() const
120 return type == ATOMIC_RMW;
123 bool ModelAction::is_rmwc() const
125 return type == ATOMIC_RMWC;
128 bool ModelAction::is_fence() const
130 return type == ATOMIC_FENCE;
133 bool ModelAction::is_initialization() const
135 return type == ATOMIC_INIT;
138 bool ModelAction::is_acquire() const
141 case std::memory_order_acquire:
142 case std::memory_order_acq_rel:
143 case std::memory_order_seq_cst:
150 bool ModelAction::is_release() const
153 case std::memory_order_release:
154 case std::memory_order_acq_rel:
155 case std::memory_order_seq_cst:
162 bool ModelAction::is_seqcst() const
164 return order==std::memory_order_seq_cst;
167 bool ModelAction::same_var(const ModelAction *act) const
169 return location == act->location;
172 bool ModelAction::same_thread(const ModelAction *act) const
174 return tid == act->tid;
177 void ModelAction::copy_typeandorder(ModelAction * act) {
178 this->type = act->type;
179 this->order = act->order;
182 /** This method changes an existing read part of an RMW action into either:
183 * (1) a full RMW action in case of the completed write or
184 * (2) a READ action in case a failed action.
185 * @todo If the memory_order changes, we may potentially need to update our
188 void ModelAction::process_rmw(ModelAction * act) {
189 this->order=act->order;
191 this->type=ATOMIC_READ;
192 else if (act->is_rmw()) {
193 this->type=ATOMIC_RMW;
194 this->value=act->value;
198 /** The is_synchronizing method should only explore interleavings if:
199 * (1) the operations are seq_cst and don't commute or
200 * (2) the reordering may establish or break a synchronization relation.
201 * Other memory operations will be dealt with by using the reads_from
204 * @param act is the action to consider exploring a reordering.
205 * @return tells whether we have to explore a reordering.
207 bool ModelAction::could_synchronize_with(const ModelAction *act) const
209 //Same thread can't be reordered
210 if (same_thread(act))
213 // Different locations commute
217 // Explore interleavings of seqcst writes to guarantee total order
218 // of seq_cst operations that don't commute
219 if ((is_write() || act->is_write()) && is_seqcst() && act->is_seqcst())
222 // Explore synchronizing read/write pairs
223 if (is_read() && is_acquire() && act->is_write() && act->is_release())
226 // Otherwise handle by reads_from relation
230 bool ModelAction::is_conflicting_lock(const ModelAction *act) const
232 //Must be different threads to reorder
233 if (same_thread(act))
236 //Try to reorder a lock past a successful lock
237 if (act->is_success_lock())
240 //Try to push a successful trylock past an unlock
241 if (act->is_unlock() && is_trylock() && value == VALUE_TRYSUCCESS)
248 * Create a new clock vector for this action. Note that this function allows a
249 * user to clobber (and leak) a ModelAction's existing clock vector. A user
250 * should ensure that the vector has already either been rolled back
251 * (effectively "freed") or freed.
253 * @param parent A ModelAction from which to inherit a ClockVector
255 void ModelAction::create_cv(const ModelAction *parent)
258 cv = new ClockVector(parent->cv, this);
260 cv = new ClockVector(NULL, this);
263 void ModelAction::set_try_lock(bool obtainedlock) {
265 value=VALUE_TRYSUCCESS;
267 value=VALUE_TRYFAILED;
271 * Update the model action's read_from action
272 * @param act The action to read from; should be a write
273 * @return True if this read established synchronization
275 bool ModelAction::read_from(const ModelAction *act)
279 if (act != NULL && this->is_acquire()) {
280 rel_heads_list_t release_heads;
281 model->get_release_seq_heads(this, &release_heads);
282 int num_heads = release_heads.size();
283 for (unsigned int i = 0; i < release_heads.size(); i++)
284 if (!synchronize_with(release_heads[i])) {
285 model->set_bad_synchronization();
288 return num_heads > 0;
294 * Synchronize the current thread with the thread corresponding to the
295 * ModelAction parameter.
296 * @param act The ModelAction to synchronize with
297 * @return True if this is a valid synchronization; false otherwise
299 bool ModelAction::synchronize_with(const ModelAction *act) {
300 if (*this < *act && type != THREAD_JOIN && type != ATOMIC_LOCK)
302 model->check_promises(act->get_tid(), cv, act->cv);
307 bool ModelAction::has_synchronized_with(const ModelAction *act) const
309 return cv->has_synchronized_with(act->cv);
313 * Check whether 'this' happens before act, according to the memory-model's
314 * happens before relation. This is checked via the ClockVector constructs.
315 * @return true if this action's thread has synchronized with act's thread
316 * since the execution of act, false otherwise.
318 bool ModelAction::happens_before(const ModelAction *act) const
320 return act->cv->synchronized_since(this);
323 /** @brief Print nicely-formatted info about this ModelAction */
324 void ModelAction::print() const
326 const char *type_str, *mo_str;
327 switch (this->type) {
328 case MODEL_FIXUP_RELSEQ:
329 type_str = "relseq fixup";
332 type_str = "thread create";
335 type_str = "thread start";
338 type_str = "thread yield";
341 type_str = "thread join";
344 type_str = "thread finish";
347 type_str = "atomic read";
350 type_str = "atomic write";
353 type_str = "atomic rmw";
359 type_str = "atomic rmwr";
362 type_str = "atomic rmwc";
365 type_str = "init atomic";
374 type_str = "trylock";
377 type_str = "unknown type";
380 uint64_t valuetoprint=type==ATOMIC_READ?(reads_from!=NULL?reads_from->value:VALUE_NONE):value;
382 switch (this->order) {
383 case std::memory_order_relaxed:
386 case std::memory_order_acquire:
389 case std::memory_order_release:
392 case std::memory_order_acq_rel:
395 case std::memory_order_seq_cst:
403 printf("(%3d) Thread: %-2d Action: %-13s MO: %7s Loc: %14p Value: %-12" PRIu64,
404 seq_number, id_to_int(tid), type_str, mo_str, location, valuetoprint);
407 printf(" Rf: %d", reads_from->get_seq_number());