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Function caller in linux kernel

Is there a way to get function caller in linux kernel? I know __func__ returns the function name which is executing. I am looking for the function which called "__func__"

Solution

  • You can get the caller with __builtin_return_address(0).

    The caller's caller is __builtin_return_address(1) and so on.

    It's a GCC extension, documented in the gcc manual: http://gcc.gnu.org/onlinedocs/gcc/Return-Address.html

    Edit: I should probably point out, that gets you the address of the caller. If you want the function name you can print it with %pS, eg:

    printk("Caller is %pS\n", __builtin_return_address(0));

    If you don't want to print it, you can use kallsyms_lookup() etc.