X-Git-Url: http://plrg.eecs.uci.edu/git/?p=model-checker.git;a=blobdiff_plain;f=schedule.cc;h=1cd5b0f1a9f3db7410965a8afad7e67f27a360d3;hp=0f550c41962a5046c6934fe5380d17e0cda39e36;hb=d884d14a6288f1ee1809158e81ffb05bf83f483b;hpb=1873837128eca281cb7ccae1ca564af56e1e10b4 diff --git a/schedule.cc b/schedule.cc index 0f550c4..1cd5b0f 100644 --- a/schedule.cc +++ b/schedule.cc @@ -1,48 +1,192 @@ -#include "threads.h" +#include +#include + +#include "threads-model.h" #include "schedule.h" #include "common.h" #include "model.h" +#include "nodestack.h" +/** Constructor */ +Scheduler::Scheduler() : + enabled(NULL), + enabled_len(0), + curr_thread_index(0), + current(NULL) +{ +} + +void Scheduler::set_enabled(Thread *t, enabled_type_t enabled_status) { + int threadid=id_to_int(t->get_id()); + if (threadid>=enabled_len) { + enabled_type_t *new_enabled = (enabled_type_t *)snapshot_malloc(sizeof(enabled_type_t) * (threadid + 1)); + memset(&new_enabled[enabled_len], 0, (threadid+1-enabled_len)*sizeof(enabled_type_t)); + if (enabled != NULL) { + memcpy(new_enabled, enabled, enabled_len*sizeof(enabled_type_t)); + snapshot_free(enabled); + } + enabled=new_enabled; + enabled_len=threadid+1; + } + enabled[threadid]=enabled_status; +} + +/** + * @brief Check if a Thread is currently enabled + * @param t The Thread to check + * @return True if the Thread is currently enabled + */ +bool Scheduler::is_enabled(Thread *t) const +{ + int id = id_to_int(t->get_id()); + return (id >= enabled_len) ? false : (enabled[id] != THREAD_DISABLED); +} + +enabled_type_t Scheduler::get_enabled(Thread *t) { + int id = id_to_int(t->get_id()); + ASSERT(idget_enabled_array(); + for(int i=0;iget_id())); + set_enabled(t, THREAD_SLEEP_SET); +} + +/** + * Remove a Thread from the sleep set. + * @param t The Thread to remove + */ +void Scheduler::remove_sleep(Thread *t) +{ + DEBUG("thread %d\n", id_to_int(t->get_id())); + set_enabled(t, THREAD_ENABLED); +} + +/** + * Add a Thread to the scheduler's ready list. + * @param t The Thread to add + */ void Scheduler::add_thread(Thread *t) { - DEBUG("thread %d\n", t->get_id()); - readyList.push_back(t); + DEBUG("thread %d\n", id_to_int(t->get_id())); + ASSERT(!t->is_model_thread()); + set_enabled(t, THREAD_ENABLED); +} + +/** + * Remove a given Thread from the scheduler. + * @param t The Thread to remove + */ +void Scheduler::remove_thread(Thread *t) +{ + if (current == t) + current = NULL; + set_enabled(t, THREAD_DISABLED); +} + +/** + * Prevent a Thread from being scheduled. The sleeping Thread should be + * re-awoken via Scheduler::wake. + * @param thread The Thread that should sleep + */ +void Scheduler::sleep(Thread *t) +{ + set_enabled(t, THREAD_DISABLED); + t->set_state(THREAD_BLOCKED); +} + +/** + * Wake a Thread up that was previously waiting (see Scheduler::wait) + * @param t The Thread to wake up + */ +void Scheduler::wake(Thread *t) +{ + ASSERT(!t->is_model_thread()); + set_enabled(t, THREAD_ENABLED); + t->set_state(THREAD_READY); } -Thread *Scheduler::next_thread(void) +/** + * Select a Thread. This implementation defaults to round-robin, if a + * thread is not already provided. + * + * @param t Thread to run, if chosen by an external entity (e.g., + * ModelChecker). May be NULL to indicate no external choice. + * @return The next Thread to run + */ +Thread * Scheduler::next_thread(Thread *t) { - Thread *t = model->schedule_next_thread(); + if ( t == NULL ) { + int old_curr_thread = curr_thread_index; + bool have_enabled_thread_with_priority=false; + Node *n=model->get_curr_node(); + + for(int i=0;ihas_priority(tid)) { + //Have a thread with priority + if (enabled[i]!=THREAD_DISABLED) + have_enabled_thread_with_priority=true; + } + } - if (t != NULL) { - current = t; - readyList.remove(t); - } else if (readyList.empty()) { + while(true) { + curr_thread_index = (curr_thread_index+1) % enabled_len; + thread_id_t curr_tid=int_to_id(curr_thread_index); + if (enabled[curr_thread_index]==THREAD_ENABLED&& + (!have_enabled_thread_with_priority||n->has_priority(curr_tid))) { + t = model->get_thread(curr_tid); + break; + } + if (curr_thread_index == old_curr_thread) { + print(); + return NULL; + } + } + } else if (t->is_model_thread()) { + /* model-checker threads never run */ t = NULL; } else { - t = readyList.front(); - current = t; - readyList.pop_front(); + curr_thread_index = id_to_int(t->get_id()); } + current = t; print(); - return t; } -Thread *Scheduler::get_current_thread(void) +/** + * @return The currently-running Thread + */ +Thread * Scheduler::get_current_thread() const { + ASSERT(!current || !current->is_model_thread()); return current; } -void Scheduler::print() +/** + * Print debugging information about the current state of the scheduler. Only + * prints something if debugging is enabled. + */ +void Scheduler::print() const { if (current) - printf("Current thread: %d\n", current->get_id()); + DEBUG("Current thread: %d\n", id_to_int(current->get_id())); else - printf("No current thread\n"); - printf("Num. threads in ready list: %ld\n", readyList.size()); - - std::list::iterator it; - for (it = readyList.begin(); it != readyList.end(); it++) - printf("In ready list: thread %d\n", (*it)->get_id()); + DEBUG("No current thread\n"); }