X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=nodestack.cc;h=5a65821188fa0698de88a3c03684abea0f12adc8;hb=ab9a8cb068ff8fbc2f913c2c4be0fb4cede98743;hp=2eba02cf20c9739e85227c77ac7510fb4cdd4427;hpb=e725e347266a91be41447dba497f57f3b6d5413c;p=c11tester.git diff --git a/nodestack.cc b/nodestack.cc index 2eba02cf..730c7024 100644 --- a/nodestack.cc +++ b/nodestack.cc @@ -1,170 +1,679 @@ +#define __STDC_FORMAT_MACROS +#include + +#include + #include "nodestack.h" #include "action.h" #include "common.h" #include "model.h" +#include "threads-model.h" +#include "modeltypes.h" -int Node::total_nodes = 0; - -Node::Node(ModelAction *act, int nthreads) - : action(act), +/** + * @brief Node constructor + * + * Constructs a single Node for use in a NodeStack. Each Node is associated + * with exactly one ModelAction (exception: the first Node should be created + * as an empty stub, to represent the first thread "choice") and up to one + * parent. + * + * @param act The ModelAction to associate with this Node. May be NULL. + * @param par The parent Node in the NodeStack. May be NULL if there is no + * parent. + * @param nthreads The number of threads which exist at this point in the + * execution trace. + */ +Node::Node(ModelAction *act, Node *par, int nthreads, Node *prevfairness) : + read_from_status(READ_FROM_PAST), + action(act), + parent(par), num_threads(nthreads), explored_children(num_threads), - backtrack(num_threads) + backtrack(num_threads), + fairness(num_threads), + numBacktracks(0), + enabled_array(NULL), + read_from_past(), + read_from_past_idx(0), + future_values(), + future_index(-1), + relseq_break_writes(), + relseq_break_index(0), + misc_index(0), + misc_max(0) { - total_nodes++; + ASSERT(act); + act->set_node(this); + int currtid = id_to_int(act->get_tid()); + int prevtid = prevfairness ? id_to_int(prevfairness->action->get_tid()) : 0; + + if (model->params.fairwindow != 0) { + for (int i = 0; i < num_threads; i++) { + ASSERT(i < ((int)fairness.size())); + struct fairness_info *fi = &fairness[i]; + struct fairness_info *prevfi = (parent && i < parent->get_num_threads()) ? &parent->fairness[i] : NULL; + if (prevfi) { + *fi = *prevfi; + } + if (parent && parent->is_enabled(int_to_id(i))) { + fi->enabled_count++; + } + if (i == currtid) { + fi->turns++; + fi->priority = false; + } + /* Do window processing */ + if (prevfairness != NULL) { + if (prevfairness->parent->is_enabled(int_to_id(i))) + fi->enabled_count--; + if (i == prevtid) { + fi->turns--; + } + /* Need full window to start evaluating + * conditions + * If we meet the enabled count and have no + * turns, give us priority */ + if ((fi->enabled_count >= model->params.enabledcount) && + (fi->turns == 0)) + fi->priority = true; + } + } + } } +/** @brief Node desctructor */ Node::~Node() { - if (action) - delete action; + delete action; + if (enabled_array) + model_free(enabled_array); } -void Node::print() +/** Prints debugging info for the ModelAction associated with this Node */ +void Node::print() const { - if (action) - action->print(); - else - printf("******** empty action ********\n"); + action->print(); + model_print(" backtrack: %s", backtrack_empty() ? "empty" : "non-empty "); + for (int i = 0; i < (int)backtrack.size(); i++) + if (backtrack[i] == true) + model_print("[%d]", i); + model_print("\n"); + + model_print(" read from past: %s", read_from_past_empty() ? "empty" : "non-empty "); + for (int i = read_from_past_idx + 1; i < (int)read_from_past.size(); i++) + model_print("[%d]", read_from_past[i]->get_seq_number()); + model_print("\n"); + + model_print(" future values: %s", future_value_empty() ? "empty" : "non-empty "); + for (int i = future_index + 1; i < (int)future_values.size(); i++) + model_print("[%#" PRIx64 "]", future_values[i].value); + model_print("\n"); + + model_print(" promises: %s\n", promise_empty() ? "empty" : "non-empty"); + model_print(" misc: %s\n", misc_empty() ? "empty" : "non-empty"); + model_print(" rel seq break: %s\n", relseq_break_empty() ? "empty" : "non-empty"); } -bool Node::has_been_explored(thread_id_t tid) +/** + * Sets a promise to explore meeting with the given node. + * @param i is the promise index. + */ +void Node::set_promise(unsigned int i, bool is_rmw) { - int id = id_to_int(tid); - return explored_children[id]; + if (i >= promises.size()) + promises.resize(i + 1, PROMISE_IGNORE); + if (promises[i] == PROMISE_IGNORE) { + promises[i] = PROMISE_UNFULFILLED; + if (is_rmw) + promises[i] |= PROMISE_RMW; + } } -bool Node::backtrack_empty() +/** + * Looks up whether a given promise should be satisfied by this node. + * @param i The promise index. + * @return true if the promise should be satisfied by the given model action. + */ +bool Node::get_promise(unsigned int i) const { - unsigned int i; - for (i = 0; i < backtrack.size(); i++) - if (backtrack[i] == true) + return (i < promises.size()) && ((promises[i] & PROMISE_MASK) == PROMISE_FULFILLED); +} + +/** + * Increments to the next combination of promises. + * @return true if we have a valid combination. + */ +bool Node::increment_promise() +{ + DBG(); + unsigned int rmw_count = 0; + for (unsigned int i = 0; i < promises.size(); i++) { + if (promises[i] == (PROMISE_RMW|PROMISE_FULFILLED)) + rmw_count++; + } + + for (unsigned int i = 0; i < promises.size(); i++) { + if ((promises[i] & PROMISE_MASK) == PROMISE_UNFULFILLED) { + if ((rmw_count > 0) && (promises[i] & PROMISE_RMW)) { + //sending our value to two rmws... not going to work..try next combination + continue; + } + promises[i] = (promises[i] & PROMISE_RMW) | PROMISE_FULFILLED; + while (i > 0) { + i--; + if ((promises[i] & PROMISE_MASK) == PROMISE_FULFILLED) + promises[i] = (promises[i] & PROMISE_RMW) | PROMISE_UNFULFILLED; + } + return true; + } else if (promises[i] == (PROMISE_RMW|PROMISE_FULFILLED)) { + rmw_count--; + } + } + return false; +} + +/** + * Returns whether the promise set is empty. + * @return true if we have explored all promise combinations. + */ +bool Node::promise_empty() const +{ + bool fulfilledrmw = false; + for (int i = promises.size() - 1; i >= 0; i--) { + if (promises[i] == PROMISE_UNFULFILLED) return false; + if (!fulfilledrmw && ((promises[i] & PROMISE_MASK) == PROMISE_UNFULFILLED)) + return false; + if (promises[i] == (PROMISE_FULFILLED | PROMISE_RMW)) + fulfilledrmw = true; + } return true; } -void Node::explore_child(ModelAction *act) +void Node::set_misc_max(int i) { - act->set_node(this); + misc_max = i; +} + +int Node::get_misc() const +{ + return misc_index; +} + +bool Node::increment_misc() +{ + return (misc_index < misc_max) && ((++misc_index) < misc_max); +} + +bool Node::misc_empty() const +{ + return (misc_index + 1) >= misc_max; +} + +/** + * Checks if the Thread associated with this thread ID has been explored from + * this Node already. + * @param tid is the thread ID to check + * @return true if this thread choice has been explored already, false + * otherwise + */ +bool Node::has_been_explored(thread_id_t tid) const +{ + int id = id_to_int(tid); + return explored_children[id]; +} + +/** + * Checks if the backtracking set is empty. + * @return true if the backtracking set is empty + */ +bool Node::backtrack_empty() const +{ + return (numBacktracks == 0); +} + +/** + * Mark the appropriate backtracking information for exploring a thread choice. + * @param act The ModelAction to explore + */ +void Node::explore_child(ModelAction *act, enabled_type_t *is_enabled) +{ + if (!enabled_array) + enabled_array = (enabled_type_t *)model_malloc(sizeof(enabled_type_t) * num_threads); + if (is_enabled != NULL) + memcpy(enabled_array, is_enabled, sizeof(enabled_type_t) * num_threads); + else { + for (int i = 0; i < num_threads; i++) + enabled_array[i] = THREAD_DISABLED; + } + explore(act->get_tid()); } +/** + * Records a backtracking reference for a thread choice within this Node. + * Provides feedback as to whether this thread choice is already set for + * backtracking. + * @return false if the thread was already set to be backtracked, true + * otherwise + */ bool Node::set_backtrack(thread_id_t id) { int i = id_to_int(id); + ASSERT(i < ((int)backtrack.size())); if (backtrack[i]) return false; backtrack[i] = true; + numBacktracks++; return true; } thread_id_t Node::get_next_backtrack() { - /* TODO: find next backtrack */ + /** @todo Find next backtrack */ unsigned int i; for (i = 0; i < backtrack.size(); i++) if (backtrack[i] == true) break; - if (i >= backtrack.size()) - return THREAD_ID_T_NONE; + /* Backtrack set was empty? */ + ASSERT(i != backtrack.size()); + backtrack[i] = false; + numBacktracks--; return int_to_id(i); } -bool Node::is_enabled(Thread *t) +void Node::clear_backtracking() { - return id_to_int(t->get_id()) < num_threads; + for (unsigned int i = 0; i < backtrack.size(); i++) + backtrack[i] = false; + for (unsigned int i = 0; i < explored_children.size(); i++) + explored_children[i] = false; } -void Node::explore(thread_id_t tid) +bool Node::is_enabled(Thread *t) const { - int i = id_to_int(tid); - backtrack[i] = false; - explored_children[i] = true; + int thread_id = id_to_int(t->get_id()); + return thread_id < num_threads && (enabled_array[thread_id] != THREAD_DISABLED); +} + +enabled_type_t Node::enabled_status(thread_id_t tid) const +{ + int thread_id = id_to_int(tid); + if (thread_id < num_threads) + return enabled_array[thread_id]; + else + return THREAD_DISABLED; +} + +bool Node::is_enabled(thread_id_t tid) const +{ + int thread_id = id_to_int(tid); + return thread_id < num_threads && (enabled_array[thread_id] != THREAD_DISABLED); } -static void clear_node_list(node_list_t *list, node_list_t::iterator start, - node_list_t::iterator end) +bool Node::has_priority(thread_id_t tid) const { - node_list_t::iterator it; + return fairness[id_to_int(tid)].priority; +} + +/*********************************** read from ********************************/ - for (it = start; it != end; it++) - delete (*it); - list->erase(start, end); +/** + * Get the current state of the may-read-from set iteration + * @return The read-from type we should currently be checking (past or future) + */ +read_from_type_t Node::get_read_from_status() +{ + if (read_from_status == READ_FROM_PAST && read_from_past.empty()) + increment_read_from(); + return read_from_status; } -NodeStack::NodeStack() +/** + * Iterate one step in the may-read-from iteration. This includes a step in + * reading from the either the past or the future. + * @return True if there is a new read-from to explore; false otherwise + */ +bool Node::increment_read_from() { - node_list.push_back(new Node()); - iter = node_list.begin(); + promises.clear(); + if (increment_read_from_past()) { + read_from_status = READ_FROM_PAST; + return true; + } else if (increment_future_value()) { + read_from_status = READ_FROM_FUTURE; + return true; + } + read_from_status = READ_FROM_NONE; + return false; } -NodeStack::~NodeStack() +/** + * @return True if there are any new read-froms to explore + */ +bool Node::read_from_empty() const +{ + return read_from_past_empty() && future_value_empty(); +} + +/** + * Get the total size of the may-read-from set, including both past and future + * values + * @return The size of may-read-from + */ +unsigned int Node::read_from_size() const +{ + return read_from_past.size() + future_values.size(); +} + +/******************************* end read from ********************************/ + +/****************************** read from past ********************************/ + +/** @brief Prints info about read_from_past set */ +void Node::print_read_from_past() +{ + for (unsigned int i = 0; i < read_from_past.size(); i++) + read_from_past[i]->print(); +} + +/** + * Add an action to the read_from_past set. + * @param act is the action to add + */ +void Node::add_read_from_past(const ModelAction *act) +{ + read_from_past.push_back(act); +} + +/** + * Gets the next 'read_from_past' action from this Node. Only valid for a node + * where this->action is a 'read'. + * @return The first element in read_from_past + */ +const ModelAction * Node::get_read_from_past() const +{ + if (read_from_past_idx < read_from_past.size()) + return read_from_past[read_from_past_idx]; + else + return NULL; +} + +const ModelAction * Node::get_read_from_past(int i) const +{ + return read_from_past[i]; +} + +int Node::get_read_from_past_size() const +{ + return read_from_past.size(); +} + +/** + * Checks whether the readsfrom set for this node is empty. + * @return true if the readsfrom set is empty. + */ +bool Node::read_from_past_empty() const +{ + return ((read_from_past_idx + 1) >= read_from_past.size()); +} + +/** + * Increments the index into the readsfrom set to explore the next item. + * @return Returns false if we have explored all items. + */ +bool Node::increment_read_from_past() +{ + DBG(); + if (read_from_past_idx < read_from_past.size()) { + read_from_past_idx++; + return read_from_past_idx < read_from_past.size(); + } + return false; +} + +/************************** end read from past ********************************/ + +/****************************** future values *********************************/ + +/** + * Adds a value from a weakly ordered future write to backtrack to. This + * operation may "fail" if the future value has already been run (within some + * sloppiness window of this expiration), or if the futurevalues set has + * reached its maximum. + * @see model_params.maxfuturevalues + * + * @param value is the value to backtrack to. + * @return True if the future value was successully added; false otherwise + */ +bool Node::add_future_value(struct future_value fv) +{ + uint64_t value = fv.value; + modelclock_t expiration = fv.expiration; + thread_id_t tid = fv.tid; + int idx = -1; /* Highest index where value is found */ + for (unsigned int i = 0; i < future_values.size(); i++) { + if (future_values[i].value == value && future_values[i].tid == tid) { + if (expiration <= future_values[i].expiration) + return false; + idx = i; + } + } + if (idx > future_index) { + /* Future value hasn't been explored; update expiration */ + future_values[idx].expiration = expiration; + return true; + } else if (idx >= 0 && expiration <= future_values[idx].expiration + model->params.expireslop) { + /* Future value has been explored and is within the "sloppy" window */ + return false; + } + + /* Limit the size of the future-values set */ + if (model->params.maxfuturevalues > 0 && + (int)future_values.size() >= model->params.maxfuturevalues) + return false; + + future_values.push_back(fv); + return true; +} + +/** + * Gets the next 'future_value' from this Node. Only valid for a node where + * this->action is a 'read'. + * @return The first element in future_values + */ +struct future_value Node::get_future_value() const { - clear_node_list(&node_list, node_list.begin(), node_list.end()); + ASSERT(future_index >= 0 && future_index < ((int)future_values.size())); + return future_values[future_index]; } -void NodeStack::print() +/** + * Checks whether the future_values set for this node is empty. + * @return true if the future_values set is empty. + */ +bool Node::future_value_empty() const { - node_list_t::iterator it; - printf("............................................\n"); - printf("NodeStack printing node_list:\n"); - for (it = node_list.begin(); it != node_list.end(); it++) { - if (it == this->iter) - printf("vvv following action is the current iterator vvv\n"); - (*it)->print(); + return ((future_index + 1) >= ((int)future_values.size())); +} + +/** + * Increments the index into the future_values set to explore the next item. + * @return Returns false if we have explored all values. + */ +bool Node::increment_future_value() +{ + DBG(); + if (future_index < ((int)future_values.size())) { + future_index++; + return (future_index < ((int)future_values.size())); } - printf("............................................\n"); + return false; +} + +/************************** end future values *********************************/ + +/** + * Add a write ModelAction to the set of writes that may break the release + * sequence. This is used during replay exploration of pending release + * sequences. This Node must correspond to a release sequence fixup action. + * + * @param write The write that may break the release sequence. NULL means we + * allow the release sequence to synchronize. + */ +void Node::add_relseq_break(const ModelAction *write) +{ + relseq_break_writes.push_back(write); +} + +/** + * Get the write that may break the current pending release sequence, + * according to the replay / divergence pattern. + * + * @return A write that may break the release sequence. If NULL, that means + * the release sequence should not be broken. + */ +const ModelAction * Node::get_relseq_break() const +{ + if (relseq_break_index < (int)relseq_break_writes.size()) + return relseq_break_writes[relseq_break_index]; + else + return NULL; } -ModelAction * NodeStack::explore_action(ModelAction *act, ModelAction *parent) +/** + * Increments the index into the relseq_break_writes set to explore the next + * item. + * @return Returns false if we have explored all values. + */ +bool Node::increment_relseq_break() { DBG(); + promises.clear(); + if (relseq_break_index < ((int)relseq_break_writes.size())) { + relseq_break_index++; + return (relseq_break_index < ((int)relseq_break_writes.size())); + } + return false; +} + +/** + * @return True if all writes that may break the release sequence have been + * explored + */ +bool Node::relseq_break_empty() const +{ + return ((relseq_break_index + 1) >= ((int)relseq_break_writes.size())); +} + +void Node::explore(thread_id_t tid) +{ + int i = id_to_int(tid); + ASSERT(i < ((int)backtrack.size())); + if (backtrack[i]) { + backtrack[i] = false; + numBacktracks--; + } + explored_children[i] = true; +} - ASSERT(!node_list.empty()); +NodeStack::NodeStack() : + node_list(), + head_idx(-1), + total_nodes(0) +{ + total_nodes++; +} + +NodeStack::~NodeStack() +{ + for (unsigned int i = 0; i < node_list.size(); i++) + delete node_list[i]; +} + +void NodeStack::print() const +{ + model_print("............................................\n"); + model_print("NodeStack printing node_list:\n"); + for (unsigned int it = 0; it < node_list.size(); it++) { + if ((int)it == this->head_idx) + model_print("vvv following action is the current iterator vvv\n"); + node_list[it]->print(); + } + model_print("............................................\n"); +} - if (get_head()->has_been_explored(act->get_tid())) { - /* Discard duplicate ModelAction */ - delete act; - iter++; - } else { /* Diverging from previous execution */ - /* Clear out remainder of list */ - node_list_t::iterator it = iter; - it++; - clear_node_list(&node_list, it, node_list.end()); +/** Note: The is_enabled set contains what actions were enabled when + * act was chosen. */ +ModelAction * NodeStack::explore_action(ModelAction *act, enabled_type_t *is_enabled) +{ + DBG(); + + if ((head_idx + 1) < (int)node_list.size()) { + head_idx++; + return node_list[head_idx]->get_action(); + } - /* Record action */ - get_head()->explore_child(act); - act->create_cv(parent); - node_list.push_back(new Node(act, model->get_num_threads())); - iter++; + /* Record action */ + Node *head = get_head(); + Node *prevfairness = NULL; + if (head) { + head->explore_child(act, is_enabled); + if (model->params.fairwindow != 0 && head_idx > (int)model->params.fairwindow) + prevfairness = node_list[head_idx - model->params.fairwindow]; } - return (*iter)->get_action(); + + int next_threads = model->get_num_threads(); + if (act->get_type() == THREAD_CREATE) + next_threads++; + node_list.push_back(new Node(act, head, next_threads, prevfairness)); + total_nodes++; + head_idx++; + return NULL; +} + +/** + * Empties the stack of all trailing nodes after a given position and calls the + * destructor for each. This function is provided an offset which determines + * how many nodes (relative to the current replay state) to save before popping + * the stack. + * @param numAhead gives the number of Nodes (including this Node) to skip over + * before removing nodes. + */ +void NodeStack::pop_restofstack(int numAhead) +{ + /* Diverging from previous execution; clear out remainder of list */ + unsigned int it = head_idx + numAhead; + for (unsigned int i = it; i < node_list.size(); i++) + delete node_list[i]; + node_list.resize(it); + node_list.back()->clear_backtracking(); } -Node * NodeStack::get_head() +Node * NodeStack::get_head() const { - if (node_list.empty()) + if (node_list.empty() || head_idx < 0) return NULL; - return *iter; + return node_list[head_idx]; } -Node * NodeStack::get_next() +Node * NodeStack::get_next() const { - node_list_t::iterator it = iter; if (node_list.empty()) { DEBUG("Empty\n"); return NULL; } - it++; - if (it == node_list.end()) { + unsigned int it = head_idx + 1; + if (it == node_list.size()) { DEBUG("At end\n"); return NULL; } - return *it; + return node_list[it]; } void NodeStack::reset_execution() { - iter = node_list.begin(); + head_idx = -1; }