* @brief Thread functions.
*/
-#include "libthreads.h"
+#include <string.h>
+
+#include <threads.h>
#include "common.h"
-#include "threads.h"
+#include "threads-model.h"
/* global "model" object */
#include "model.h"
/** Allocate a stack for a new thread. */
static void * stack_allocate(size_t size)
{
- return malloc(size);
+ return snapshot_malloc(size);
}
/** Free a stack for a terminated thread. */
static void stack_free(void *stack)
{
- free(stack);
+ snapshot_free(stack);
}
/** Return the currently executing thread. */
-
Thread * thread_current(void)
{
ASSERT(model);
- return model->scheduler->get_current_thread();
+ return model->get_current_thread();
}
/**
/* Call the actual thread function */
curr_thread->start_routine(curr_thread->arg);
+
+ /* Finish thread properly */
+ model->switch_to_master(new ModelAction(THREAD_FINISH, std::memory_order_seq_cst, curr_thread));
}
-/** Create a thread context for a new thread so we can use
- * setcontext/getcontext/swapcontext to swap it out.
- * @return 0 on success.
+/**
+ * Create a thread context for a new thread so we can use
+ * setcontext/getcontext/swapcontext to swap it out.
+ * @return 0 on success; otherwise, non-zero error condition
*/
-
int Thread::create_context()
{
int ret;
/**
* Swaps the current context to another thread of execution. This form switches
* from a user Thread to a system context.
- * @param t Thread representing the current context
- * @param ctxt Context to switch to
+ * @param t Thread representing the currently-running thread. The current
+ * context is saved here.
+ * @param ctxt Context to which we will swap. Must hold a valid system context.
* @return Does not return, unless we return to Thread t's context. See
* swapcontext(3) (returns 0 for success, -1 for failure).
*/
/**
* Swaps the current context to another thread of execution. This form switches
* from a system context to a user Thread.
- * @param t Thread representing the current context
- * @param ctxt Context to switch to
- * @return Does not return, unless we return to Thread t's context. See
+ * @param ctxt System context variable to which to save the current context.
+ * @param t Thread to which we will swap. Must hold a valid user context.
+ * @return Does not return, unless we return to the system context (ctxt). See
* swapcontext(3) (returns 0 for success, -1 for failure).
*/
int Thread::swap(ucontext_t *ctxt, Thread *t)
/** Terminate a thread and free its stack. */
void Thread::complete()
{
- if (state != THREAD_COMPLETED) {
- DEBUG("completed thread %d\n", get_id());
+ if (!is_complete()) {
+ DEBUG("completed thread %d\n", id_to_int(get_id()));
state = THREAD_COMPLETED;
if (stack)
stack_free(stack);
}
}
-/** 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. */
+/**
+ * @brief Construct a new model-checker Thread
+ *
+ * A model-checker Thread is used for accounting purposes only. It will never
+ * have its own stack, and it should never be inserted into the Scheduler.
+ *
+ * @param tid The thread ID to assign
+ */
+Thread::Thread(thread_id_t tid) :
+ parent(NULL),
+ creation(NULL),
+ pending(NULL),
+ start_routine(NULL),
+ arg(NULL),
+ stack(NULL),
+ user_thread(NULL),
+ id(tid),
+ state(THREAD_READY), /* Thread is always ready? */
+ wait_list(),
+ last_action_val(0),
+ model_thread(true)
+{
+ memset(&context, 0, sizeof(context));
+}
+/**
+ * Construct a new thread.
+ * @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) :
+ creation(NULL),
+ pending(NULL),
start_routine(func),
arg(a),
user_thread(t),
state(THREAD_CREATED),
- last_action_val(VALUE_NONE)
+ wait_list(),
+ last_action_val(VALUE_NONE),
+ model_thread(false)
{
int ret;
parent = thread_current();
}
+/** Destructor */
Thread::~Thread()
{
complete();
model->remove_thread(this);
}
-/** Return the thread_id_t corresponding to this Thread object. */
-
+/** @return The thread_id_t corresponding to this Thread object. */
thread_id_t Thread::get_id()
{
return id;