X-Git-Url: http://plrg.eecs.uci.edu/git/?p=model-checker.git;a=blobdiff_plain;f=action.cc;h=140d59098f8c37732753e4f80ddc58f8a883810b;hp=f0ad48feaf731d808f69212b5926170e4ce96905;hb=fe7b400edb33255770fb47ad520afbd05d13a231;hpb=20926923f6de1790fdd368d5e7fa1738abe7b9a6 diff --git a/action.cc b/action.cc index f0ad48f..140d590 100644 --- a/action.cc +++ b/action.cc @@ -1,29 +1,119 @@ #include #define __STDC_FORMAT_MACROS #include +#include #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, uint64_t value) : +#define ACTION_INITIAL_CLOCK 0 + +/** + * @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), - cv(NULL) + node(NULL), + seq_number(ACTION_INITIAL_CLOCK), + cv(NULL), + sleep_flag(false) { - Thread *t = thread_current(); + /* References to NULL atomic variables can end up here */ + ASSERT(loc || type == MODEL_FIXUP_RELSEQ); + + Thread *t = thread ? thread : thread_current(); this->tid = t->get_id(); - this->seq_number = model->get_next_seq_num(); } +/** @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_failed_trylock() const +{ + return (type == ATOMIC_TRYLOCK && value == VALUE_TRYFAILED); } bool ModelAction::is_read() const @@ -36,6 +126,11 @@ 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; @@ -51,6 +146,11 @@ 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; @@ -87,6 +187,19 @@ bool ModelAction::is_seqcst() const 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; } @@ -96,18 +209,16 @@ bool ModelAction::same_thread(const ModelAction *act) const } void ModelAction::copy_typeandorder(ModelAction * act) { - this->type=act->type; - this->order=act->order; + 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. */ - -//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()) @@ -127,8 +238,7 @@ void ModelAction::process_rmw(ModelAction * act) { * @param act is the action to consider exploring a reordering. * @return tells whether we have to explore a reordering. */ - -bool ModelAction::is_synchronizing(const ModelAction *act) const +bool ModelAction::could_synchronize_with(const ModelAction *act) const { //Same thread can't be reordered if (same_thread(act)) @@ -140,37 +250,122 @@ bool ModelAction::is_synchronizing(const ModelAction *act) const // 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; + + //lock just released...we can grab lock + if ((is_lock() ||is_trylock()) && (act->is_unlock()||act->is_wait())) return true; - if (is_write() && is_release() && act->is_read() && act->is_acquire()) + + //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(const 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::set_try_lock(bool obtainedlock) { + if (obtainedlock) + value=VALUE_TRYSUCCESS; + else + value=VALUE_TRYFAILED; +} -/** Update the model action's read_from action */ -void ModelAction::read_from(const ModelAction *act) +/** + * 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); 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; +} + +bool ModelAction::has_synchronized_with(const ModelAction *act) const +{ + return cv->has_synchronized_with(act->cv); } /** @@ -184,10 +379,14 @@ bool ModelAction::happens_before(const ModelAction *act) const return act->cv->synchronized_since(this); } -void ModelAction::print(void) const +/** @brief Print nicely-formatted info about this ModelAction */ +void ModelAction::print() const { - const char *type_str; + 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; @@ -200,6 +399,9 @@ void ModelAction::print(void) const case THREAD_JOIN: type_str = "thread join"; break; + case THREAD_FINISH: + type_str = "thread finish"; + break; case ATOMIC_READ: type_str = "atomic read"; break; @@ -209,6 +411,9 @@ void ModelAction::print(void) const case ATOMIC_RMW: type_str = "atomic rmw"; break; + case ATOMIC_FENCE: + type_str = "fence"; + break; case ATOMIC_RMWR: type_str = "atomic rmwr"; break; @@ -218,19 +423,80 @@ void ModelAction::print(void) const 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=type==ATOMIC_READ?(reads_from!=NULL?reads_from->value:VALUE_NONE):value; - printf("(%3d) Thread: %-2d Action: %-13s MO: %d Loc: %14p Value: %-12" PRIu64, - seq_number, id_to_int(tid), type_str, order, location, valuetoprint); - if (reads_from) - printf(" Rf: %d", reads_from->get_seq_number()); + 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; +}