trace

리눅스에서의 로그 레벨(linux/kernel.h)

level define
0 #define KERN_EMERG "<0>" / * system is unusable */
1 #define KERN_ALERT "<1>" / * action must be taken immediately */
2 #define KERN_CRIT "<2>" / * critical conditions */
3 #define KERN_ERR "<3>" / * error conditions */
4 #define KERN_WARNING "<4>" / * WARNING conditions */
5 #define KERN_NOTICE "<5>" / * normal but significant condition */
6 #define KERN_INFO "<6>" / * informational */
7 #define KERN_DEBUG "<7>" / * debug-level messages */

printk

dump_stack

ftrace