init && exit

source/module/Makefile_bak

@@ -1,3 +0,0 @@
-KMOD = variable_monitor
-obj-m := $(KMOD).o
-$(KMOD)-objs := monitor_kernel.o

source/module/monitor_kallsyms.c

@@ -17,7 +17,7 @@ int (*orig_kernfs_name)(struct kernfs_node *kn, char *buf, size_t buflen);
 int (*orig_access_remote_vm)(struct mm_struct *mm, unsigned long addr,
                              void *buf, int len, unsigned int gup_flags);
 
-/// @brief init kallsyms_lookup_name
+/// @brief init kallsyms_lookup_name,all orig_fun are depend on it
 /// @param
 /// @return 0 is success
 static int fn_kallsyms_lookup_name_init(void) {
@@ -25,7 +25,7 @@ static int fn_kallsyms_lookup_name_init(void) {
   diag_kallsyms_lookup_name = (void *)kprobe_kallsyms_lookup_name.addr;
   unregister_kprobe(&kprobe_kallsyms_lookup_name);
 
-  printk("xby-debug, diag_kallsyms_lookup_name is %p\n",
+  printk(KERN_INFO "diag_kallsyms_lookup_name is %p\n",
          diag_kallsyms_lookup_name);
 
   if (!diag_kallsyms_lookup_name) {
@@ -33,15 +33,27 @@ static int fn_kallsyms_lookup_name_init(void) {
   }
   return 0;
 }
-
+/**
+ * @brief get all orig_fun
+ *
+ * @return int 0 is success
+ */
 int init_orig_fun(void) {
-  fn_kallsyms_lookup_name_init();    // init kallsyms_lookup_name
-  LOOKUP_SYMS(stack_trace_save_tsk); // stack_trace_save_tsk
-  LOOKUP_SYMS(show_stack);           // show_stack
-  LOOKUP_SYMS(idle_sched_class);     // idle_sched_class
-  LOOKUP_SYMS(access_remote_vm);     // access_remote_vm
+  int ret = fn_kallsyms_lookup_name_init();  // init kallsyms_lookup_name
 
-  LOOKUP_SYMS_NORET(get_task_type); // get_task_type
-  LOOKUP_SYMS_NORET(kernfs_name);   // kernfs_name
+  if (ret)
+  {
+    printk(KERN_INFO "init kallsyms_lookup_name failed\n");
+    return ret;
+  }
+
+  LOOKUP_SYMS(stack_trace_save_tsk);  // stack_trace_save_tsk
+  LOOKUP_SYMS(show_stack);            // show_stack
+  LOOKUP_SYMS(idle_sched_class);      // idle_sched_class
+  LOOKUP_SYMS(access_remote_vm);      // access_remote_vm
+
+  LOOKUP_SYMS_NORET(
+      get_task_type);  // get_task_type | this fun is not available on 5.17.15
+  LOOKUP_SYMS_NORET(kernfs_name);  // kernfs_name
   return 0;
 }

source/module/monitor_kernel.c

@@ -64,7 +64,7 @@ static struct file_operations fops = {
 };
 
 int init_module(void) {
-  printk(KERN_INFO "%s\n", __FUNCTION__);
+  printk(KERN_INFO "variable_monitor fun: %s\n", __FUNCTION__);
   if (alloc_chrdev_region(&dev_num, 0, 1, DEVICE_NAME) < 0) {
     printk(KERN_ALERT "Failed to register device number\n");
     return -1;
@@ -110,7 +110,7 @@ int init_module(void) {
 }
 
 void cleanup_module(void) {
-  printk(KERN_INFO "%s\n", __FUNCTION__);
+  printk(KERN_INFO "variable_monitor fun: %s\n", __FUNCTION__);
   // clear all watch | free buffer
   monitor_exit();
 

source/module/monitor_kernel_lib.c

@@ -12,8 +12,8 @@ static unsigned char w_arg2k_w_arg(void *ptr, watch_arg warg,
                                    kernel_watch_arg *k_watch_arg) {
   // k_watch_arg init
   k_watch_arg->task_id = warg.task_id;
-  strncpy(k_watch_arg->name, warg.name, MAX_NAME_LEN + 1); // name
-  k_watch_arg->name[MAX_NAME_LEN + 1] = '\0';              // just in case
+  strncpy(k_watch_arg->name, warg.name, MAX_NAME_LEN + 1);  // name
+  k_watch_arg->name[MAX_NAME_LEN + 1] = '\0';               // just in case
   k_watch_arg->kptr = ptr;
   k_watch_arg->length_byte = warg.length_byte;
   k_watch_arg->threshold = warg.threshold;
@@ -28,7 +28,7 @@ static void init_mm_tree(mm_tree *mm_tree) {
 }
 
 static int init_buffer(unsigned int buf_size) {
-  init_mm_tree(&mm_tree_struct); // init mm_tree
+  init_mm_tree(&mm_tree_struct);  // init mm_tree
   init_diag_variant_buffer(&load_monitor_variant_buffer, buf_size);
   int ret = 0;
   ret = alloc_diag_variant_buffer(&load_monitor_variant_buffer);
@@ -56,10 +56,10 @@ static void clear_all_watch(void) {
 int monitor_init(void) {
   int ret = 0;
 
-  init_orig_fun();                     // init orig_X
-  ret = init_buffer(50 * 1024 * 1024); // 50M
-  if (ret)
-    return 0;
+  ret = init_orig_fun();  // init orig_X
+  if (ret) return ret;
+  ret = init_buffer(50 * 1024 * 1024);  // 50M
+  if (ret) return -1;
   return 0;
 }
 
@@ -72,6 +72,7 @@ void monitor_exit() {
   clear_all_watch();
   // free buffer
   destroy_diag_variant_buffer(&load_monitor_variant_buffer);
+  printk(KERN_INFO "clear all buffer\n");
 }
 /**
  * @brief start watch variable
@@ -99,7 +100,7 @@ int start_watch_variable(watch_arg warg) {
   }
   // k_watch_arg init
   w_arg2k_w_arg(kptr, warg, &k_watch_arg);
-  timer = get_timer(warg.time_ns); // get a valuable timer
+  timer = get_timer(warg.time_ns);  // get a valuable timer
 
   printk(KERN_INFO "ptr transform kptr: %p\n", kptr);
   printk(KERN_INFO "timer: %p\n", timer);
@@ -107,7 +108,7 @@ int start_watch_variable(watch_arg warg) {
          timer->sentinel, timer->time_ns);
   printk(KERN_INFO "timer->hr_timer: %p\n", &timer->hr_timer);
 
-  TIMER_CANCEL(timer); // just in case
+  TIMER_CANCEL(timer);  // just in case
   timer_add_watch(timer, k_watch_arg);
   TIMER_START(timer);
 
@@ -122,8 +123,8 @@ int start_watch_variable(watch_arg warg) {
  */
 void clear_watch(pid_t pid) {
   printk(KERN_INFO "clear pid %d 's watch variable\n", pid);
-  cancel_all_hrTimer();      // just in case
-  del_all_kwarg_by_pid(pid); // delete all kwarg with pid
-  free_page_list(pid);       // free page with pid
-  start_all_hrTimer();       // restart timer
+  cancel_all_hrTimer();       // just in case
+  del_all_kwarg_by_pid(pid);  // delete all kwarg with pid
+  free_page_list(pid);        // free page with pid
+  start_all_hrTimer();        // restart timer
 }

source/module/monitor_timer.c

@@ -200,5 +200,5 @@ void cancel_all_hrTimer(void) {
     TIMER_CANCEL(timer);
   }
 
-  printk("HrTimer cancel,module keep %d hrtimer for now\n", kernel_wtimer_num);
+  printk(KERN_INFO "HrTimer cancel,module keep %d hrtimer for now\n", kernel_wtimer_num);
 }