Re: Linux Kernel GDB tracepoint module 2010-8-30 release

Frank Ch. Eigler
2010-09-04T05:11:50Z

Hi -

On Sat, Sep 04, 2010 at 12:29:56PM +0800, Hui Zhu wrote:

> [...] Could you talk about how it do call stack dump like following?
> (gdb) trace vfs_readdir
> Tracepoint 1 at 0xffffffff8113f7fc: file
> /home/teawater/kernel/linux-2.6/fs/readdir.c, line 24.
> (gdb) actions
> >collect *(unsigned char *)$rsp@512

probe kernel.function("vfs_readdir") {
// if you want the whole kernel-side backtrace, dwarf-unwound
print_backtrace()
// or else just hex-dump a region
printf("%*M\n", 512, register("rsp"))
}

> BTW, I was not find out which ARCH of the systemtap support in its
> website? It support all the arch that kprobe support?

Yes, basically, though it's mostly tested on RHELy platforms (x86,
powerpc, s390, ia64).

- FChE