mark pages removed from page/mmap table as clear

1 files changed, 4 insertions, 6 deletions

diff --git a/userprog/process.c b/userprog/process.c
index 80e327d..bf1a706 100644
--- a/userprog/process.c
+++ b/userprog/process.c
@@ -129,6 +129,7 @@ start_process (void *aux)
   process->parent_tid = aux_data->parent_thread->tid;
   thread->process = process;
 
+  /* initialize page and mmap table */
   page_table_init (&thread->page_table);
   if (!mmap_table_init (&process->mmap_table))
     goto signal;
@@ -151,10 +152,9 @@ start_process (void *aux)
   /* If process startup failed, quit. */
   if (thread->process == NULL)  {
     if (process != NULL) {
+      /* close/free memory mapped files and page table */
       /* close/free memory mapped files */
       mmap_table_free (&process->mmap_table);
-
-      /* free page table */
       page_table_free (&thread->page_table);
 
       if (process->fd_table.fds != NULL)
@@ -240,8 +240,9 @@ process_exit (void)
     lock_release (&filesys_lock);
   }
 
-  /* close/free memory mapped files */
+  /* close/free memory mapped files and page table */
   mmap_table_free (&proc->mmap_table);
+  page_table_free (&thread->page_table);
 
   int fd;
   for (fd = 2; fd <= proc->fd_table.fd_max; fd++) {
@@ -265,9 +266,6 @@ process_exit (void)
     pagedir_destroy (pd);
   }
 
-  /* free page table */
-  page_table_free (&thread->page_table);
-
   /* Destroy the process structure if the parent is not alive
    * any more. Atomic test and set would be sufficient here.
    */