diff --git a/kernel/defs.h b/kernel/defs.h
index 6bc6444..6a16310 100644
--- a/kernel/defs.h
+++ b/kernel/defs.h
@@ -188,6 +188,9 @@ void            vmprint(pagetable_t);
 pte_t*          pgpte(pagetable_t, uint64);
 void            superfree(void *pa);
 void*           superalloc();
+int             copyin_new(pagetable_t, char *, uint64, uint64);
+int             copyinstr_new(pagetable_t, char *, uint64, uint64);
+uint64          sys_dirtypages(void);
 #endif
 
 // plic.c
@@ -204,14 +207,6 @@ void            virtio_disk_intr(void);
 // number of elements in fixed-size array
 #define NELEM(x) (sizeof(x)/sizeof((x)[0]))
 
-
-
-#ifdef LAB_PGTBL
-// vmcopyin.c
-int             copyin_new(pagetable_t, char *, uint64, uint64);
-int             copyinstr_new(pagetable_t, char *, uint64, uint64);
-#endif
-
 #ifdef LAB_LOCK
 // stats.c
 void            statsinit(void);
diff --git a/time.txt b/time.txt
new file mode 100644
index 0000000..901184c
--- /dev/null
+++ b/time.txt
@@ -0,0 +1 @@
+88888888
diff --git a/user/usys.pl b/user/usys.pl
index 216ff87..e0777d1 100755
--- a/user/usys.pl
+++ b/user/usys.pl
@@ -43,3 +43,4 @@ entry("recv");
 entry("pgpte");
 entry("kpgtbl");
 entry("pgaccess");
+entry("dirtypages");