weenix

1 files changed, 37 insertions, 3 deletions

diff --git a/kernel/proc/kthread.c b/kernel/proc/kthread.c
index d066dac..b614ac3 100644
--- a/kernel/proc/kthread.c
+++ b/kernel/proc/kthread.c
@@ -121,8 +121,42 @@ kthread_t *kthread_create(proc_t *proc, kthread_func_t func, long arg1,
  */
 kthread_t *kthread_clone(kthread_t *thr)
 {
-    NOT_YET_IMPLEMENTED("VM: kthread_clone");
-    return NULL;
+    // NOT_YET_IMPLEMENTED("VM: kthread_clone");
+
+    kthread_t *new_thread = slab_obj_alloc(kthread_allocator);
+    if (new_thread == NULL)
+    {
+        return NULL;
+    }
+    new_thread->kt_state = KT_NO_STATE;
+
+    // copy the stack
+    new_thread->kt_ctx.c_kstack = alloc_stack();
+    if (new_thread->kt_kstack == NULL)
+    {
+        slab_obj_free(kthread_allocator, new_thread);
+        return NULL;
+    }
+    new_thread->kt_kstack = new_thread->kt_ctx.c_kstack;
+    new_thread->kt_ctx.c_kstacksz = DEFAULT_STACK_SIZE;
+
+    // context_setup(&new_thread->kt_ctx, NULL, 0, NULL, new_thread->kt_kstack, 
+    //     DEFAULT_STACK_SIZE, thr->kt_proc->p_pml4); (done in fork, I hope)
+
+    // set the retval, errno, cancelled
+    new_thread->kt_retval = thr->kt_retval;
+    new_thread->kt_errno = thr->kt_errno;
+    new_thread->kt_cancelled = thr->kt_cancelled;
+    new_thread->kt_preemption_count = 0;
+    new_thread->kt_recent_core = ~0UL;
+    new_thread->kt_wchan = NULL;
+    // freshly initialize the rest of the fields
+    list_init(&new_thread->kt_mutexes);
+    list_link_init(&new_thread->kt_plink);
+    list_link_init(&new_thread->kt_qlink);
+    // list_insert_tail(&thr->kt_proc->p_threads, &new_thread->kt_plink); (done in fork)
+
+    return new_thread;
 }
 
 /*
@@ -162,7 +196,7 @@ void kthread_cancel(kthread_t *thr, void *retval)
     // NOT_YET_IMPLEMENTED("PROCS: kthread_cancel");
     KASSERT(thr != curthr);
 
-    // FIXME: ask about the use of check_curthr_cancelled() in syscall_handler()
+    // ask about the use of check_curthr_cancelled() in syscall_handler()
     int status = (int) retval;
     dbg(DBG_THR, "Cancelling thread with proc name=%s, id=%d, status=%d\n", 
         thr->kt_proc->p_name, thr->kt_proc->p_pid, status);