This is the mail archive of the
systemtap@sourceware.org
mailing list for the systemtap project.
Re: socket-trace.stp: no match while resolving probe point kernel.function("*@net/socket.c")
On Mon, 2008-11-03 at 12:50 +0100, Mark Wielaard wrote:
> On Wed, 2008-10-29 at 21:41 -0400, Dongtao Liu wrote:
> > Thank you for reply. I found it pretty strange that if I do not use
> > "*@net/socket.c" but use function in socket.c directly such as
> > sock_create. SystemTap can work well and trace all the calls of
> > fuction sock_create. I don't know why...
>
> That is indeed strange. So this works for you:
> $ stap -e 'probe kernel.function("sock_sendmsg"){log(pp())}'
> But this doesn't:
> $ stap -e 'probe kernel.function("sock_sendmsg@net/socket.c"){log(pp())}'
>
> Does the output (pp()) of the running version, or if you run it with
> -vv, give any hints about the why?
I got another report of this issue, from srikar, but this time on SLES.
stap is 0.7.1 and elfutils 0.137, kernel 2.6.27.4-2-pae
When its not working it says:
ï semantic error: libdw failure (dwarf_getsrcfiles): invalid DWARF
ïsemantic error: no match while resolving probe point kernel.function("sock_sendmsg@net/socket.c").call
When working:
ï kernel.function("sock_sendmsg@net/socket.c:569")
So it looks like the file name is actually there, but libdw doesn't like
how it is encoded. I filed a new bug report for this:
http://sourceware.org/bugzilla/show_bug.cgi?id=7010
Cheers,
Mark