#include <stdio.h>
#define __STDC_FORMAT_MACROS
#include <inttypes.h>
-#include <vector>
+#include <stdlib.h>
#include "model.h"
#include "action.h"
#define ACTION_INITIAL_CLOCK 0
+/** @brief A special value to represent a successful trylock */
+#define VALUE_TRYSUCCESS 1
+
+/** @brief A special value to represent a failed trylock */
+#define VALUE_TRYFAILED 0
+
/**
* @brief Construct a new ModelAction
*
location(loc),
value(value),
reads_from(NULL),
+ reads_from_promise(NULL),
last_fence_release(NULL),
node(NULL),
seq_number(ACTION_INITIAL_CLOCK),
return type == THREAD_START;
}
+bool ModelAction::is_thread_join() const
+{
+ return type == THREAD_JOIN;
+}
+
bool ModelAction::is_relseq_fixup() const
{
return type == MODEL_FIXUP_RELSEQ;
return is_write() || is_rmwr();
}
+bool ModelAction::is_yield() const
+{
+ return type == THREAD_YIELD;
+}
+
bool ModelAction::is_rmwr() const
{
return type == ATOMIC_RMWR;
*/
Thread * ModelAction::get_thread_operand() const
{
- if (type == THREAD_CREATE)
- /* THREAD_CREATE uses (Thread *) for location */
- return (Thread *)get_location();
- else if (type == THREAD_JOIN)
+ if (type == THREAD_CREATE) {
+ /* THREAD_CREATE stores its (Thread *) in a thrd_t::priv */
+ thrd_t *thrd = (thrd_t *)get_location();
+ return thrd->priv;
+ } else if (type == THREAD_JOIN)
/* THREAD_JOIN uses (Thread *) for location */
return (Thread *)get_location();
else
return NULL;
}
-/** 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.
+/**
+ * @brief Convert the read portion of an RMW
+ *
+ * Changes an existing read part of an RMW action into either:
+ * -# a full RMW action in case of the completed write or
+ * -# a READ action in case a failed action.
+ *
* @todo If the memory_order changes, we may potentially need to update our
* clock vector.
+ *
+ * @param act The second half of the RMW (either RMWC or RMW)
*/
void ModelAction::process_rmw(ModelAction *act)
{
}
}
-/** 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.
- * Other memory operations will be dealt with by using the reads_from
- * relation.
+/**
+ * @brief Check if this action should be backtracked with another, due to
+ * potential synchronization
+ *
+ * The is_synchronizing method should only explore interleavings if:
+ * -# the operations are seq_cst and don't commute or
+ * -# the reordering may establish or break a synchronization relation.
+ *
+ * Other memory operations will be dealt with by using the reads_from relation.
*
- * @param act is the action to consider exploring a reordering.
- * @return tells whether we have to explore a reordering.
+ * @param act The action to consider exploring a reordering
+ * @return True, if we have to explore a reordering; otherwise false
*/
bool ModelAction::could_synchronize_with(const ModelAction *act) const
{
// Explore interleavings of seqcst writes/fences to guarantee total
// order of seq_cst operations that don't commute
- if ((could_be_write() || act->could_be_write() || is_fence() || act->is_fence())
- && is_seqcst() && act->is_seqcst())
+ if ((could_be_write() || act->could_be_write() || is_fence() || act->is_fence()) && is_seqcst() && act->is_seqcst())
return true;
- // Explore synchronizing read/write/fence pairs
- if (is_acquire() && act->is_release() && (is_read() || is_fence()) &&
- (act->could_be_write() || act->is_fence()))
+ // Explore synchronizing read/write pairs
+ if (is_acquire() && act->is_release() && is_read() && act->could_be_write())
return true;
// lock just released...we can grab lock
cv = new ClockVector(NULL, this);
}
-void ModelAction::set_try_lock(bool obtainedlock) {
- if (obtainedlock)
- value = VALUE_TRYSUCCESS;
+void ModelAction::set_try_lock(bool obtainedlock)
+{
+ value = obtainedlock ? VALUE_TRYSUCCESS : VALUE_TRYFAILED;
+}
+
+/**
+ * @brief Get the value read by this load
+ *
+ * We differentiate this function from ModelAction::get_write_value and
+ * ModelAction::get_value for the purpose of RMW's, which may have both a
+ * 'read' and a 'write' value.
+ *
+ * Note: 'this' must be a load.
+ *
+ * @return The value read by this load
+ */
+uint64_t ModelAction::get_reads_from_value() const
+{
+ ASSERT(is_read());
+ if (reads_from)
+ return reads_from->get_write_value();
+ else if (reads_from_promise)
+ return reads_from_promise->get_value();
+ return VALUE_NONE; /* Only for new actions with no reads-from */
+}
+
+/**
+ * @brief Get the value written by this store
+ *
+ * We differentiate this function from ModelAction::get_reads_from_value and
+ * ModelAction::get_value for the purpose of RMW's, which may have both a
+ * 'read' and a 'write' value.
+ *
+ * Note: 'this' must be a store.
+ *
+ * @return The value written by this store
+ */
+uint64_t ModelAction::get_write_value() const
+{
+ ASSERT(is_write());
+ return value;
+}
+
+/**
+ * @brief Get the value returned by this action
+ *
+ * For atomic reads (including RMW), an operation returns the value it read.
+ * For atomic writes, an operation returns the value it wrote. For other
+ * operations, the return value varies (sometimes is a "don't care"), but the
+ * value is simply stored in the "value" field.
+ *
+ * @return This action's return value
+ */
+uint64_t ModelAction::get_return_value() const
+{
+ if (is_read())
+ return get_reads_from_value();
+ else if (is_write())
+ return get_write_value();
else
- value = VALUE_TRYFAILED;
+ return value;
}
/** @return The Node associated with this ModelAction */
*/
void ModelAction::set_read_from(const ModelAction *act)
{
+ ASSERT(act);
reads_from = act;
reads_from_promise = NULL;
- if (act && act->is_uninitialized())
- model->assert_bug("May read from uninitialized atomic\n");
+ if (act->is_uninitialized())
+ model->assert_bug("May read from uninitialized atomic:\n"
+ " action %d, thread %d, location %p (%s, %s)",
+ seq_number, id_to_int(tid), location,
+ get_type_str(), get_mo_str());
}
/**
* Set this action's read-from promise
* @param promise The promise to read from
*/
-void ModelAction::set_read_from_promise(const Promise *promise)
+void ModelAction::set_read_from_promise(Promise *promise)
{
ASSERT(is_read());
reads_from_promise = promise;
*/
bool ModelAction::synchronize_with(const ModelAction *act)
{
- if (*this < *act && type != THREAD_JOIN && type != ATOMIC_LOCK)
+ if (*this < *act)
return false;
- model->check_promises(act->get_tid(), cv, act->cv);
cv->merge(act->cv);
return true;
}
return act->cv->synchronized_since(this);
}
-/** @brief Print nicely-formatted info about this ModelAction */
-void ModelAction::print() const
+const char * ModelAction::get_type_str() 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_UNINIT:
- type_str = "uninitialized";
- break;
- case ATOMIC_READ:
- type_str = "atomic read";
- break;
- case ATOMIC_WRITE:
- type_str = "atomic write";
- 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";
- }
-
- uint64_t valuetoprint;
- if (is_read() && reads_from)
- valuetoprint = reads_from->value;
- else if (is_read() && reads_from_promise)
- valuetoprint = reads_from_promise->get_value();
- else
- valuetoprint = value;
-
+ case MODEL_FIXUP_RELSEQ: return "relseq fixup";
+ case THREAD_CREATE: return "thread create";
+ case THREAD_START: return "thread start";
+ case THREAD_YIELD: return "thread yield";
+ case THREAD_JOIN: return "thread join";
+ case THREAD_FINISH: return "thread finish";
+ case ATOMIC_UNINIT: return "uninitialized";
+ case ATOMIC_READ: return "atomic read";
+ case ATOMIC_WRITE: return "atomic write";
+ case ATOMIC_RMW: return "atomic rmw";
+ case ATOMIC_FENCE: return "fence";
+ case ATOMIC_RMWR: return "atomic rmwr";
+ case ATOMIC_RMWC: return "atomic rmwc";
+ case ATOMIC_INIT: return "init atomic";
+ case ATOMIC_LOCK: return "lock";
+ case ATOMIC_UNLOCK: return "unlock";
+ case ATOMIC_TRYLOCK: return "trylock";
+ case ATOMIC_WAIT: return "wait";
+ case ATOMIC_NOTIFY_ONE: return "notify one";
+ case ATOMIC_NOTIFY_ALL: return "notify all";
+ default: return "unknown type";
+ };
+}
+
+const char * ModelAction::get_mo_str() const
+{
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;
+ case std::memory_order_relaxed: return "relaxed";
+ case std::memory_order_acquire: return "acquire";
+ case std::memory_order_release: return "release";
+ case std::memory_order_acq_rel: return "acq_rel";
+ case std::memory_order_seq_cst: return "seq_cst";
+ default: return "unknown";
}
+}
+
+/** @brief Print nicely-formatted info about this ModelAction */
+void ModelAction::print() const
+{
+ const char *type_str = get_type_str(), *mo_str = get_mo_str();
- model_print("(%4d) Thread: %-2d Action: %-13s MO: %7s Loc: %14p Value: %-#18" PRIx64,
- seq_number, id_to_int(tid), type_str, mo_str, location, valuetoprint);
+ model_print("%-4d %-2d %-13s %7s %14p %-#18" PRIx64,
+ seq_number, id_to_int(tid), type_str, mo_str, location, get_return_value());
if (is_read()) {
if (reads_from)
- model_print(" Rf: %-3d", reads_from->get_seq_number());
- else
- model_print(" Rf: ? ");
+ model_print(" %-3d", reads_from->get_seq_number());
+ else if (reads_from_promise) {
+ int idx = reads_from_promise->get_index();
+ if (idx >= 0)
+ model_print(" P%-2d", idx);
+ else
+ model_print(" P? ");
+ } else
+ model_print(" ? ");
}
if (cv) {
if (is_read())
model_print(" ");
else
- model_print(" ");
+ model_print(" ");
cv->print();
} else
model_print("\n");
hash ^= seq_number << 5;
hash ^= id_to_int(tid) << 6;
- if (is_read() && reads_from)
- hash ^= reads_from->get_seq_number();
+ if (is_read()) {
+ if (reads_from)
+ hash ^= reads_from->get_seq_number();
+ else if (reads_from_promise)
+ hash ^= reads_from_promise->get_index();
+ hash ^= get_reads_from_value();
+ }
return hash;
}
+
+/**
+ * @brief Checks the NodeStack to see if a ModelAction is in our may-read-from set
+ * @param write The ModelAction to check for
+ * @return True if the ModelAction is found; false otherwise
+ */
+bool ModelAction::may_read_from(const ModelAction *write) const
+{
+ for (int i = 0; i < node->get_read_from_past_size(); i++)
+ if (node->get_read_from_past(i) == write)
+ return true;
+ return false;
+}
+
+/**
+ * @brief Checks the NodeStack to see if a Promise is in our may-read-from set
+ * @param promise The Promise to check for
+ * @return True if the Promise is found; false otherwise
+ */
+bool ModelAction::may_read_from(const Promise *promise) const
+{
+ for (int i = 0; i < node->get_read_from_promise_size(); i++)
+ if (node->get_read_from_promise(i) == promise)
+ return true;
+ return false;
+}
+
+/**
+ * Only valid for LOCK, TRY_LOCK, UNLOCK, and WAIT operations.
+ * @return The mutex operated on by this action, if any; otherwise NULL
+ */
+std::mutex * ModelAction::get_mutex() const
+{
+ if (is_trylock() || is_lock() || is_unlock())
+ return (std::mutex *)get_location();
+ else if (is_wait())
+ return (std::mutex *)get_value();
+ else
+ return NULL;
+}