update codes

code/lab7/kern/mm/memlayout.h

@@ -127,7 +127,7 @@ struct e820map {
  * that convert Page to other data types, such as phyical address.
  * */
 struct Page {
-    atomic_t ref;                   // page frame's reference counter
+    int ref;                        // page frame's reference counter
     uint32_t flags;                 // array of flags that describe the status of the page frame
     unsigned int property;          // used in buddy system, stores the order (the X in 2^X) of the continuous memory block
     int zone_num;                   // used in buddy system, the No. of zone which the page belongs to

code/lab7/kern/mm/pmm.h

@@ -121,22 +121,24 @@ pde2page(pde_t pde) {
 
 static inline int
 page_ref(struct Page *page) {
-    return atomic_read(&(page->ref));
+    return page->ref;
 }
 
 static inline void
 set_page_ref(struct Page *page, int val) {
-    atomic_set(&(page->ref), val);
+    page->ref = val;
 }
 
 static inline int
 page_ref_inc(struct Page *page) {
-    return atomic_add_return(&(page->ref), 1);
+    page->ref += 1;
+    return page->ref;
 }
 
 static inline int
 page_ref_dec(struct Page *page) {
-    return atomic_sub_return(&(page->ref), 1);
+    page->ref -= 1;
+    return page->ref;
 }
 
 extern char bootstack[], bootstacktop[];

code/lab7/kern/mm/vmm.h

@@ -35,7 +35,7 @@ struct mm_struct {
     pde_t *pgdir;                  // the PDT of these vma
     int map_count;                 // the count of these vma
     void *sm_priv;                 // the private data for swap manager
-    atomic_t mm_count;             // the number ofprocess which shared the mm
+    int mm_count;                  // the number ofprocess which shared the mm
     semaphore_t mm_sem;            // mutex for using dup_mmap fun to duplicat the mm 
     int locked_by;                 // the lock owner process's pid
 
@@ -68,22 +68,24 @@ bool copy_to_user(struct mm_struct *mm, void *dst, const void *src, size_t len);
 
 static inline int
 mm_count(struct mm_struct *mm) {
-    return atomic_read(&(mm->mm_count));
+    return mm->mm_count;
 }
 
 static inline void
 set_mm_count(struct mm_struct *mm, int val) {
-    atomic_set(&(mm->mm_count), val);
+    mm->mm_count = val;
 }
 
 static inline int
 mm_count_inc(struct mm_struct *mm) {
-    return atomic_add_return(&(mm->mm_count), 1);
+    mm->mm_count += 1;
+    return mm->mm_count;
 }
 
 static inline int
 mm_count_dec(struct mm_struct *mm) {
-    return atomic_sub_return(&(mm->mm_count), 1);
+    mm->mm_count -= 1;
+    return mm->mm_count;
 }
 
 static inline void