X-Git-Url: http://plrg.eecs.uci.edu/git/?p=model-checker.git;a=blobdiff_plain;f=threads.cc;h=792014e62b4d3c88c1ecc052a4de120c25cace52;hp=be384fb2889b1fdc85f16ae89e6274b8de833636;hb=84e24d516d4e9dbd30f1fff7e9a185d1540d20eb;hpb=d279e84ed265af079ea035d5dff49183def2c144 diff --git a/threads.cc b/threads.cc index be384fb..792014e 100644 --- a/threads.cc +++ b/threads.cc @@ -1,7 +1,4 @@ -#include - #include "libthreads.h" -#include "schedule.h" #include "common.h" #include "threads.h" @@ -22,9 +19,28 @@ static void stack_free(void *stack) Thread * thread_current(void) { + ASSERT(model); return model->scheduler->get_current_thread(); } +/** + * Provides a startup wrapper for each thread, allowing some initial + * model-checking data to be recorded. This method also gets around makecontext + * not being 64-bit clean + */ +void thread_startup() { + Thread * curr_thread = thread_current(); + + /* TODO -- we should make this event always immediately follow the + CREATE event, so we don't get redundant traces... */ + + /* Add dummy "start" action, just to create a first clock vector */ + model->switch_to_master(new ModelAction(THREAD_START, std::memory_order_seq_cst, curr_thread)); + + /* Call the actual thread function */ + curr_thread->start_routine(curr_thread->arg); +} + int Thread::create_context() { int ret; @@ -33,124 +49,63 @@ int Thread::create_context() if (ret) return ret; - /* start_routine == NULL means this is our initial context */ - if (!start_routine) - return 0; - /* Initialize new managed context */ stack = stack_allocate(STACK_SIZE); context.uc_stack.ss_sp = stack; context.uc_stack.ss_size = STACK_SIZE; context.uc_stack.ss_flags = 0; - context.uc_link = &model->system_thread->context; - makecontext(&context, start_routine, 1, arg); + context.uc_link = model->get_system_context(); + makecontext(&context, thread_startup, 0); return 0; } -int Thread::swap(Thread *t) +int Thread::swap(Thread *t, ucontext_t *ctxt) { - return swapcontext(&this->context, &t->context); + return swapcontext(&t->context, ctxt); } -void Thread::dispose() +int Thread::swap(ucontext_t *ctxt, Thread *t) { - DEBUG("completed thread %d\n", thread_current()->get_id()); - state = THREAD_COMPLETED; - stack_free(stack); + return swapcontext(ctxt, &t->context); } -Thread::Thread(thrd_t *t, void (*func)(), void *a) { - int ret; +void Thread::complete() +{ + if (state != THREAD_COMPLETED) { + DEBUG("completed thread %d\n", get_id()); + state = THREAD_COMPLETED; + if (stack) + stack_free(stack); + } +} - user_thread = t; - start_routine = func; - arg = a; +Thread::Thread(thrd_t *t, void (*func)(void *), void *a) : + start_routine(func), + arg(a), + user_thread(t), + state(THREAD_CREATED), + last_action_val(VALUE_NONE) +{ + int ret; /* Initialize state */ ret = create_context(); if (ret) printf("Error in create_context\n"); - state = THREAD_CREATED; - model->assign_id(this); - model->scheduler->add_thread(this); + id = model->get_next_id(); + *user_thread = id; + parent = thread_current(); } -Thread::Thread(thrd_t *t) { - /* system thread */ - user_thread = t; - state = THREAD_CREATED; - model->assign_id(this); - create_context(); - model->add_system_thread(this); -} - -thread_id_t Thread::get_id() +Thread::~Thread() { - return thrd_to_id(*user_thread); + complete(); + model->remove_thread(this); } -/* - * Return 1 if found next thread, 0 otherwise - */ -static int thread_system_next(void) -{ - Thread *curr, *next; - - curr = thread_current(); - model->check_current_action(); - if (curr) { - if (curr->get_state() == THREAD_READY) - model->scheduler->add_thread(curr); - else if (curr->get_state() == THREAD_RUNNING) - /* Stopped while running; i.e., completed */ - curr->dispose(); - else - DEBUG("ERROR: current thread in unexpected state??\n"); - } - next = model->scheduler->next_thread(); - if (next) - next->set_state(THREAD_RUNNING); - DEBUG("(%d, %d)\n", curr ? curr->get_id() : -1, next ? next->get_id() : -1); - if (!next) - return 1; - return model->system_thread->swap(next); -} - -static void thread_wait_finish(void) -{ - - DBG(); - - while (!thread_system_next()); -} - -/* - * Main system function - */ -int main() +thread_id_t Thread::get_id() { - thrd_t user_thread, main_thread; - Thread *th; - - model = new ModelChecker(); - - th = new Thread(&main_thread); - - do { - /* Start user program */ - thrd_create(&user_thread, &user_main, NULL); - - /* Wait for all threads to complete */ - thread_wait_finish(); - - model->print_trace(); - } while (model->next_execution()); - - delete th; - delete model; - - DEBUG("Exiting\n"); - return 0; + return id; }