c - How to print the current thread stack trace inside the Linux kernel?

Question

I would like to be able to print the stack trace of a thread in the Linux kernel.

In details: I want to add code to specific functions (e.g. swap_writepage() ) that will print the complete stack trace of the thread where this function is being called. Something like this:

int swap_writepage(struct page *page, struct writeback_control *wbc)
{

    /* code goes here to print stack trace */

    int ret = 0;

    if (try_to_free_swap(page)) {
        unlock_page(page);
        goto out;
    }
    if (frontswap_store(page) == 0) {
        set_page_writeback(page);
        unlock_page(page);
        end_page_writeback(page);
        goto out;
    }
    ret = __swap_writepage(page, wbc, end_swap_bio_write);
out:
    return ret;
}

My story: Recently, Linux kernel developers started to adopt object-oriented principles when improving the kernel, which is written in C. Since C is not an OO languages things started to look very ugly and harder ti understand, let alone not having a decent IDE that can analyze C code. And I do not want to get started on running Linux under a debugger. Note: if you are a kernel development newb and want to run Linux under a debugger do not put efforts into that...it will prove to be fruitless (stepping makes no sense).

Answer 1

Linux kernel has very well known function called dump_stack() here, which prints the content of the stack. Place it in your function in according to see stack info.