#include <stdio.h>
+#define __STDC_FORMAT_MACROS
+#include <inttypes.h>
+#include <vector>
#include "model.h"
#include "action.h"
#include "clockvector.h"
#include "common.h"
+#include "threads-model.h"
+#include "nodestack.h"
-ModelAction::ModelAction(action_type_t type, memory_order order, void *loc, int value)
-{
- Thread *t = thread_current();
- ModelAction *act = this;
+#define ACTION_INITIAL_CLOCK 0
- act->type = type;
- act->order = order;
- act->location = loc;
- act->tid = t->get_id();
- act->value = value;
- act->seq_number = model->get_next_seq_num();
+/**
+ * @brief Construct a new ModelAction
+ *
+ * @param type The type of action
+ * @param order The memory order of this action. A "don't care" for non-ATOMIC
+ * actions (e.g., THREAD_* or MODEL_* actions).
+ * @param loc The location that this action acts upon
+ * @param value (optional) A value associated with the action (e.g., the value
+ * read or written). Defaults to a given macro constant, for debugging purposes.
+ * @param thread (optional) The Thread in which this action occurred. If NULL
+ * (default), then a Thread is assigned according to the scheduler.
+ */
+ModelAction::ModelAction(action_type_t type, memory_order order, void *loc,
+ uint64_t value, Thread *thread) :
+ type(type),
+ order(order),
+ location(loc),
+ value(value),
+ reads_from(NULL),
+ node(NULL),
+ seq_number(ACTION_INITIAL_CLOCK),
+ cv(NULL),
+ sleep_flag(false)
+{
+ /* References to NULL atomic variables can end up here */
+ ASSERT(loc || type == MODEL_FIXUP_RELSEQ);
- cv = NULL;
+ Thread *t = thread ? thread : thread_current();
+ this->tid = t->get_id();
}
+/** @brief ModelAction destructor */
ModelAction::~ModelAction()
{
- if (cv)
- delete cv;
+ /**
+ * We can't free the clock vector:
+ * Clock vectors are snapshotting state. When we delete model actions,
+ * they are at the end of the node list and have invalid old clock
+ * vectors which have already been rolled back to an unallocated state.
+ */
+
+ /*
+ if (cv)
+ delete cv; */
+}
+
+void ModelAction::copy_from_new(ModelAction *newaction)
+{
+ seq_number = newaction->seq_number;
+}
+
+void ModelAction::set_seq_number(modelclock_t num)
+{
+ ASSERT(seq_number == ACTION_INITIAL_CLOCK);
+ seq_number = num;
+}
+
+bool ModelAction::is_relseq_fixup() const
+{
+ return type == MODEL_FIXUP_RELSEQ;
+}
+
+bool ModelAction::is_mutex_op() const
+{
+ return type == ATOMIC_LOCK || type == ATOMIC_TRYLOCK || type == ATOMIC_UNLOCK || type == ATOMIC_WAIT || type == ATOMIC_NOTIFY_ONE || type == ATOMIC_NOTIFY_ALL;
+}
+
+bool ModelAction::is_lock() const
+{
+ return type == ATOMIC_LOCK;
+}
+
+bool ModelAction::is_wait() const {
+ return type == ATOMIC_WAIT;
+}
+
+bool ModelAction::is_notify() const {
+ return type==ATOMIC_NOTIFY_ONE || type==ATOMIC_NOTIFY_ALL;
+}
+
+bool ModelAction::is_notify_one() const {
+ return type==ATOMIC_NOTIFY_ONE;
+}
+
+bool ModelAction::is_unlock() const
+{
+ return type == ATOMIC_UNLOCK;
+}
+
+bool ModelAction::is_trylock() const
+{
+ return type == ATOMIC_TRYLOCK;
+}
+
+bool ModelAction::is_success_lock() const
+{
+ return type == ATOMIC_LOCK || (type == ATOMIC_TRYLOCK && value == VALUE_TRYSUCCESS);
}
-bool ModelAction::is_read()
+bool ModelAction::is_failed_trylock() const
{
- return type == ATOMIC_READ;
+ return (type == ATOMIC_TRYLOCK && value == VALUE_TRYFAILED);
}
-bool ModelAction::is_write()
+bool ModelAction::is_read() const
{
- return type == ATOMIC_WRITE;
+ return type == ATOMIC_READ || type == ATOMIC_RMWR || type == ATOMIC_RMW;
}
-bool ModelAction::is_rmw()
+bool ModelAction::is_write() const
+{
+ return type == ATOMIC_WRITE || type == ATOMIC_RMW || type == ATOMIC_INIT;
+}
+
+bool ModelAction::could_be_write() const
+{
+ return is_write() || is_rmwr();
+}
+
+bool ModelAction::is_rmwr() const
+{
+ return type == ATOMIC_RMWR;
+}
+
+bool ModelAction::is_rmw() const
{
return type == ATOMIC_RMW;
}
-bool ModelAction::is_acquire()
+bool ModelAction::is_rmwc() const
+{
+ return type == ATOMIC_RMWC;
+}
+
+bool ModelAction::is_fence() const
+{
+ return type == ATOMIC_FENCE;
+}
+
+bool ModelAction::is_initialization() const
+{
+ return type == ATOMIC_INIT;
+}
+
+bool ModelAction::is_acquire() const
{
switch (order) {
- case memory_order_acquire:
- case memory_order_acq_rel:
- case memory_order_seq_cst:
+ case std::memory_order_acquire:
+ case std::memory_order_acq_rel:
+ case std::memory_order_seq_cst:
return true;
default:
return false;
}
}
-bool ModelAction::is_release()
+bool ModelAction::is_release() const
{
switch (order) {
- case memory_order_release:
- case memory_order_acq_rel:
- case memory_order_seq_cst:
+ case std::memory_order_release:
+ case std::memory_order_acq_rel:
+ case std::memory_order_seq_cst:
return true;
default:
return false;
}
}
-bool ModelAction::is_seqcst()
+bool ModelAction::is_seqcst() const
{
- return order==memory_order_seq_cst;
+ return order==std::memory_order_seq_cst;
}
-bool ModelAction::same_var(ModelAction *act)
+bool ModelAction::same_var(const ModelAction *act) const
{
+ if ( act->is_wait() || is_wait() ) {
+ if ( act->is_wait() && is_wait() ) {
+ if ( ((void *)value) == ((void *)act->value) )
+ return true;
+ } else if ( is_wait() ) {
+ if ( ((void *)value) == act->location )
+ return true;
+ } else if ( act->is_wait() ) {
+ if ( location == ((void *)act->value) )
+ return true;
+ }
+ }
+
return location == act->location;
}
-bool ModelAction::same_thread(ModelAction *act)
+bool ModelAction::same_thread(const ModelAction *act) const
{
return tid == act->tid;
}
+void ModelAction::copy_typeandorder(ModelAction * act) {
+ this->type = act->type;
+ this->order = act->order;
+}
+
+/** This method changes an existing read part of an RMW action into either:
+ * (1) a full RMW action in case of the completed write or
+ * (2) a READ action in case a failed action.
+ * @todo If the memory_order changes, we may potentially need to update our
+ * clock vector.
+ */
+void ModelAction::process_rmw(ModelAction * act) {
+ this->order=act->order;
+ if (act->is_rmwc())
+ this->type=ATOMIC_READ;
+ else if (act->is_rmw()) {
+ this->type=ATOMIC_RMW;
+ this->value=act->value;
+ }
+}
+
/** The is_synchronizing method should only explore interleavings if:
* (1) the operations are seq_cst and don't commute or
* (2) the reordering may establish or break a synchronization relation.
* @param act is the action to consider exploring a reordering.
* @return tells whether we have to explore a reordering.
*/
-
-bool ModelAction::is_synchronizing(ModelAction *act)
+bool ModelAction::could_synchronize_with(const ModelAction *act) const
{
//Same thread can't be reordered
if (same_thread(act))
// Different locations commute
if (!same_var(act))
return false;
-
+
// Explore interleavings of seqcst writes to guarantee total order
// of seq_cst operations that don't commute
- if (is_write() && is_seqcst() && act->is_write() && act->is_seqcst())
+ if ((could_be_write() || act->could_be_write()) && is_seqcst() && act->is_seqcst())
return true;
// Explore synchronizing read/write pairs
- if (is_read() && is_acquire() && act->is_write() && act->is_release())
+ if (is_read() && is_acquire() && act->could_be_write() && act->is_release())
return true;
- if (is_write() && is_release() && act->is_read() && act->is_acquire())
+
+ //lock just released...we can grab lock
+ if ((is_lock() ||is_trylock()) && (act->is_unlock()||act->is_wait()))
+ return true;
+
+ //lock just acquired...we can fail to grab lock
+ if (is_trylock() && act->is_success_lock())
+ return true;
+
+ //other thread stalling on lock...we can release lock
+ if (is_unlock() && (act->is_trylock()||act->is_lock()))
+ return true;
+
+ if (is_trylock() && (act->is_unlock()||act->is_wait()))
+ return true;
+
+ if ( is_notify() && act->is_wait() )
+ return true;
+
+ if ( is_wait() && act->is_notify() )
return true;
// Otherwise handle by reads_from relation
return false;
}
-void ModelAction::create_cv(ModelAction *parent)
+bool ModelAction::is_conflicting_lock(const ModelAction *act) const
{
- ASSERT(cv == NULL);
+ //Must be different threads to reorder
+ if (same_thread(act))
+ return false;
+
+ //Try to reorder a lock past a successful lock
+ if (act->is_success_lock())
+ return true;
+
+ //Try to push a successful trylock past an unlock
+ if (act->is_unlock() && is_trylock() && value == VALUE_TRYSUCCESS)
+ return true;
+
+ //Try to push a successful trylock past a wait
+ if (act->is_wait() && is_trylock() && value == VALUE_TRYSUCCESS)
+ return true;
+
+ return false;
+}
+/**
+ * Create a new clock vector for this action. Note that this function allows a
+ * user to clobber (and leak) a ModelAction's existing clock vector. A user
+ * should ensure that the vector has already either been rolled back
+ * (effectively "freed") or freed.
+ *
+ * @param parent A ModelAction from which to inherit a ClockVector
+ */
+void ModelAction::create_cv(const ModelAction *parent)
+{
if (parent)
cv = new ClockVector(parent->cv, this);
else
cv = new ClockVector(NULL, this);
}
-void ModelAction::read_from(ModelAction *act)
+void ModelAction::set_try_lock(bool obtainedlock) {
+ if (obtainedlock)
+ value=VALUE_TRYSUCCESS;
+ else
+ value=VALUE_TRYFAILED;
+}
+
+/**
+ * Update the model action's read_from action
+ * @param act The action to read from; should be a write
+ * @return True if this read established synchronization
+ */
+bool ModelAction::read_from(const ModelAction *act)
{
ASSERT(cv);
- if (act->is_release() && this->is_acquire())
- cv->merge(act->cv);
- value = act->value;
+ reads_from = act;
+ if (act != NULL && this->is_acquire()) {
+ rel_heads_list_t release_heads;
+ model->get_release_seq_heads(this, &release_heads);
+ int num_heads = release_heads.size();
+ for (unsigned int i = 0; i < release_heads.size(); i++)
+ if (!synchronize_with(release_heads[i])) {
+ model->set_bad_synchronization();
+ num_heads--;
+ }
+ return num_heads > 0;
+ }
+ return false;
+}
+
+/**
+ * Synchronize the current thread with the thread corresponding to the
+ * ModelAction parameter.
+ * @param act The ModelAction to synchronize with
+ * @return True if this is a valid synchronization; false otherwise
+ */
+bool ModelAction::synchronize_with(const ModelAction *act) {
+ if (*this < *act && type != THREAD_JOIN && type != ATOMIC_LOCK)
+ return false;
+ model->check_promises(act->get_tid(), cv, act->cv);
+ cv->merge(act->cv);
+ return true;
}
-void ModelAction::print(void)
+bool ModelAction::has_synchronized_with(const ModelAction *act) const
{
- const char *type_str;
+ return cv->has_synchronized_with(act->cv);
+}
+
+/**
+ * Check whether 'this' happens before act, according to the memory-model's
+ * happens before relation. This is checked via the ClockVector constructs.
+ * @return true if this action's thread has synchronized with act's thread
+ * since the execution of act, false otherwise.
+ */
+bool ModelAction::happens_before(const ModelAction *act) const
+{
+ return act->cv->synchronized_since(this);
+}
+
+/** @brief Print nicely-formatted info about this ModelAction */
+void ModelAction::print() const
+{
+ const char *type_str, *mo_str;
switch (this->type) {
+ case MODEL_FIXUP_RELSEQ:
+ type_str = "relseq fixup";
+ break;
case THREAD_CREATE:
type_str = "thread create";
break;
+ case THREAD_START:
+ type_str = "thread start";
+ break;
case THREAD_YIELD:
type_str = "thread yield";
break;
case THREAD_JOIN:
type_str = "thread join";
break;
+ case THREAD_FINISH:
+ type_str = "thread finish";
+ break;
case ATOMIC_READ:
type_str = "atomic read";
break;
case ATOMIC_RMW:
type_str = "atomic rmw";
break;
+ case ATOMIC_FENCE:
+ type_str = "fence";
+ break;
+ case ATOMIC_RMWR:
+ type_str = "atomic rmwr";
+ break;
+ case ATOMIC_RMWC:
+ type_str = "atomic rmwc";
+ break;
+ case ATOMIC_INIT:
+ type_str = "init atomic";
+ break;
+ case ATOMIC_LOCK:
+ type_str = "lock";
+ break;
+ case ATOMIC_UNLOCK:
+ type_str = "unlock";
+ break;
+ case ATOMIC_TRYLOCK:
+ type_str = "trylock";
+ break;
+ case ATOMIC_WAIT:
+ type_str = "wait";
+ break;
+ case ATOMIC_NOTIFY_ONE:
+ type_str = "notify one";
+ break;
+ case ATOMIC_NOTIFY_ALL:
+ type_str = "notify all";
+ break;
default:
type_str = "unknown type";
}
- printf("(%3d) Thread: %-2d Action: %-13s MO: %d Loc: %14p Value: %d",
- seq_number, id_to_int(tid), type_str, order, location, value);
+ uint64_t valuetoprint=type==ATOMIC_READ?(reads_from!=NULL?reads_from->value:VALUE_NONE):value;
+
+ switch (this->order) {
+ case std::memory_order_relaxed:
+ mo_str = "relaxed";
+ break;
+ case std::memory_order_acquire:
+ mo_str = "acquire";
+ break;
+ case std::memory_order_release:
+ mo_str = "release";
+ break;
+ case std::memory_order_acq_rel:
+ mo_str = "acq_rel";
+ break;
+ case std::memory_order_seq_cst:
+ mo_str = "seq_cst";
+ break;
+ default:
+ mo_str = "unknown";
+ break;
+ }
+
+ printf("(%4d) Thread: %-2d Action: %-13s MO: %7s Loc: %14p Value: %-#18" PRIx64,
+ seq_number, id_to_int(tid), type_str, mo_str, location, valuetoprint);
+ if (is_read()) {
+ if (reads_from)
+ printf(" Rf: %-3d", reads_from->get_seq_number());
+ else
+ printf(" Rf: ? ");
+ }
if (cv) {
- printf("\t");
+ if (is_read())
+ printf(" ");
+ else
+ printf(" ");
cv->print();
} else
printf("\n");
}
+
+/** @brief Print nicely-formatted info about this ModelAction */
+unsigned int ModelAction::hash() const
+{
+ unsigned int hash=(unsigned int) this->type;
+ hash^=((unsigned int)this->order)<<3;
+ hash^=seq_number<<5;
+ hash ^= id_to_int(tid) << 6;
+
+ if (is_read()) {
+ if (reads_from)
+ hash^=reads_from->get_seq_number();
+ }
+ return hash;
+}
projects / model-checker.git / blobdiff