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Re: [PATCH 2/3] Implement new features needed for handling SystemTap probes
>>>>> "Mark" == Mark Kettenis <mark.kettenis@xs4all.nl> writes:
Tom> The static probes in this case are intended to be source- (but not
Tom> binary-) compatible with DTrace.
Mark> Don't you mean the other way around? As far as I can tell the
Mark> SystemTap macros have different names than their DTrace counterparts.
Mark> And I'd say that for GDB it's only binary compatibility that really
Mark> matters here.
No, the SystemTap-provided <sdt.h> has compatibility macros with the
same names as the DTrace macros.
It doesn't try to be binary-compatible. I don't know how the DTrace
<sdt.h> works at all...
Mark> So you are saying that, at least in principle, it should be possible
Mark> to use the SystemTap toolchain on any ELF-based system to do
Mark> user-space tracing without needing any kernel support? That'd be cool.
Nope, just the static markers coming from <sdt.h>. The rest of
SystemTap is Linux-specific, dynamically creating and loading kernel
modules.
The probes still have some value outside of SystemTap. With patch #3 in
this series, you can use them to better implement "next-over-throw", for
C++ debugging. This is because GCC's unwinder has a probe in it that is
used by GDB.
Tom