kernel里initcall debug

设置initcall_debug 变量,该变量在init/main.c中定义:

bool initcall_debug;

修改成

bool initcall_debug = 1;

这时编译运行,发现还没有打印initcall log,查找原因,发现是printk的loglevel 比较高,kernel debug的level比较低,
然后在/kernel/printk.c 文件中把printk的loglevel调到最低,使其打印所有的log,如下,都调整到9:

+#define DEFAULT_MESSAGE_LOGLEVEL 9 /* We show everything that is MORE important than this.. */+#define MINIMUM_CONSOLE_LOGLEVEL 9 /* Minimum loglevel we let people use */+#define DEFAULT_CONSOLE_LOGLEVEL 9 /* anything MORE serious than KERN_DEBUG */