[PATCH 0 of 3] Add support for dtrace compatible sdt probes on GNU/Linux

[Mark Wielaard]

On Tue, 2012-05-22 at 14:27 +1000, David Holmes wrote:
> Is systemTap part of regular distros these days - in particular in our 
> build environment?
> 
> I'm just wondering who is going to ensure that these probe entries 
> compile and run correctly?

Note that SDT markers are just that, markers. There is not really
something that "runs" them. But systemtap and recent GDB can find them
and use them for introspection. There are several icedtea autobuilders
that can do that:
http://builder.classpath.org/icedtea/buildbot/waterfall
This has been included through IcedTea at least on Fedora based systems
for some years now and on RHEL6 since release (2010 I believe). In
theory SDT markers on GNU/Linux should be source compatible with those
on Solaris. That was how it was designed. The make patch checks there is
a sys/sdt.h include file available, which is really all there is to it
[*] (the only difference between dtrace sdt and gnu/linux sdt markers is
how/where they are stored in the ELF file). But in practice there have
of course been bugs in compilers (but I believe any modern g++ 4.4+
compiler should do, 4.4.6 is the oldest I can find on my RHEL6 install,
current GCC version is 4.7).

Cheers,

Mark

[*] http://sourceware.org/systemtap/wiki/UserSpaceProbeImplementation