move more configurables and add documentation

[c11tester.git] / threads.cc

diff --git a/threads.cc b/threads.cc
index cc939318938170da4712191ab7ea7bd20e78140b..cde331dbfad0dde86f33394639ced4f374418fd0 100644 (file)
--- a/threads.cc
+++ b/threads.cc
@@ -1,30 +1,57 @@
-#include <stdlib.h>
+/** @file threads.cc
+ *  @brief Thread functions.
+ */
 
 #include "libthreads.h"
-#include "schedule.h"
 #include "common.h"
 #include "threads.h"
 
 /* global "model" object */
 #include "model.h"
 
-#define STACK_SIZE (1024 * 1024)
-
+/** Allocate a stack for a new thread. */
 static void * stack_allocate(size_t size)
 {
-       return userMalloc(size);
+       return malloc(size);
 }
 
+/** Free a stack for a terminated thread. */
 static void stack_free(void *stack)
 {
-       userFree(stack);
+       free(stack);
 }
 
+/** Return the currently executing thread. */
+
 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
+ * @todo We should make the START event always immediately follow the
+ * CREATE event, so we don't get redundant traces...
+ */
+
+void thread_startup() {
+       Thread * curr_thread = thread_current();
+
+       /* 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);
+}
+
+/** Create a thread context for a new thread so we can use
+ *  setcontext/getcontext/swapcontext to swap it out.
+ *  @return 0 on success.
+ */
+
 int Thread::create_context()
 {
        int ret;
@@ -39,7 +66,7 @@ int Thread::create_context()
        context.uc_stack.ss_size = STACK_SIZE;
        context.uc_stack.ss_flags = 0;
        context.uc_link = model->get_system_context();
-       makecontext(&context, start_routine, 1, arg);
+       makecontext(&context, thread_startup, 0);
 
        return 0;
 }
@@ -54,6 +81,9 @@ int Thread::swap(ucontext_t *ctxt, Thread *t)
        return swapcontext(ctxt, &t->context);
 }
 
+
+/** Terminate a thread and free its stack. */
+
 void Thread::complete()
 {
        if (state != THREAD_COMPLETED) {
@@ -64,27 +94,26 @@ void Thread::complete()
        }
 }
 
-void * Thread::operator new(size_t size) {
-       return userMalloc(size);
-}
-
-void Thread::operator delete(void *ptr) {
-       userFree(ptr);
-}
-
-Thread::Thread(thrd_t *t, void (*func)(), void *a) {
+/** Create a new thread. 
+ *  Takes the following parameters:
+ *  @param t The thread identifier of the newly created thread.
+ *  @param func  The function that the thread will call.
+ *  @param a The parameter to pass to this function. */
+
+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;
 
-       user_thread = t;
-       start_routine = func;
-       arg = a;
-
        /* Initialize state */
        ret = create_context();
        if (ret)
                printf("Error in create_context\n");
 
-       state = THREAD_CREATED;
        id = model->get_next_id();
        *user_thread = id;
        parent = thread_current();
@@ -96,71 +125,9 @@ Thread::~Thread()
        model->remove_thread(this);
 }
 
+/** Return the thread_id_t corresponding to this Thread object. */
+
 thread_id_t Thread::get_id()
 {
        return id;
 }
-
-/*
- * Return 1 if found next thread, 0 otherwise
- */
-static int thread_system_next(void)
-{
-       Thread *curr, *next;
-
-       curr = thread_current();
-       if (curr) {
-               if (curr->get_state() == THREAD_READY) {
-                       model->check_current_action();
-                       model->scheduler->add_thread(curr);
-               } else if (curr->get_state() == THREAD_RUNNING)
-                       /* Stopped while running; i.e., completed */
-                       curr->complete();
-               else
-                       ASSERT(false);
-       }
-       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 Thread::swap(model->get_system_context(), next);
-}
-
-static void thread_wait_finish(void)
-{
-
-       DBG();
-
-       while (!thread_system_next());
-}
-
-/*
- * Main system function
- */
-int main()
-{
-       thrd_t user_thread;
-       ucontext_t main_context;
-
-       model = new ModelChecker();
-
-       if (getcontext(&main_context))
-               return 1;
-
-       model->set_system_context(&main_context);
-
-       do {
-               /* Start user program */
-               model->add_thread(new Thread(&user_thread, &user_main, NULL));
-
-               /* Wait for all threads to complete */
-               thread_wait_finish();
-       } while (model->next_execution());
-
-       delete model;
-
-       DEBUG("Exiting\n");
-       return 0;
-}