Userspace probes on library functions ?

["Daniel P. Berrange" <berrange at redhat dot com>]

I'm trying to use userspace probes to trace public API calls into the
libvirt.so library. While I can trace functions in the virsh executable
without trouble, eg

  probe process("/usr/bin/virsh").function("vshInit") {
      printf("init %p", $ctl)
  }

I'm unable to trace functions that are defined in the libvirt.so

  probe process("/usr/bin/virsh").function("virConnectOpen") {
      printf("Open %p", $name)
  }

  semantic error: no match while resolving probe point process("/usr/bin/virsh").function("virConnectOpen")

I thought it might be symbol versioning that's confusing things,
so I've also tried

  probe process("/usr/bin/virsh").function("virConnectOpen@@LIBVIRT_0.0.3") {
      printf("Open %p", $name)
  }
  semantic error: no match while resolving probe point process("/usr/bin/virsh").function("virConnectOpen@@LIBVIRT_0.0.3")

Nor do I seem to be able to use function() matches in combination
with a library() statement

  probe process("/usr/bin/virsh").library("libvirt.so").function("virConnectOpen") {
      printf("Open %s", $name)
  }

  semantic error: probe point mismatch at position 2 (alternatives:
    mark(string) provider(string)): keyword at demo.stp:9:55 while
    resolving probe point process("/usr/bin/virsh").library("libvirt.so").function("virConnectOpen")
        source: probe process("/usr/bin/virsh").library("libvirt.so").function("virConnectOpen") {

I'm using  systemtap-1.3-2.fc13.x86_64, and have got the -debuginfo 
installed for the libvirt.so library & virsh tool. Am I simply trying
todo something that isn't supported ? If so, I'll just switch to adding
static probe markers to the public API entry/exit points instead..

Regards,
Daniel
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