Re: [PATCH] Fix compilation errors for itrace probe point

[David Smith <dsmith at redhat dot com>]

Maynard Johnson wrote:
> Hello,
> I recently pulled down the systemtap src onto a Fedora 10 system and tried to use the itrace
> probe point.  The resulting kernel module failed to compile because
the runtime/itrace.c file
> had not been updated to reflect the recent utrace interface changes.
This problem had not
> been caught because the itrace test is currently disabled (since it
fails on x86_64).

I looked at your changes a bit.  In remove_usr_itrace_info(), you
probably need to ignore EALREADY (which means the DEATH callback has
already begun so there is no point in detaching).

The changes look reasonable, but with a bit more effort you should be
able to support both the original utrace interface (for systems like
RHEL5) and the new utrace interface simultaneously.  The task_finder
layer does this now - look for '#ifdef UTRACE_ORIG_VERSION' sections and
look at runtime/utrace_compatibility.h.  Basically you write to the new
interface and use the defines and wrappers in
runtime/utrace_compatibility.h to make the original utrace interface
look like the new interface.

It is possible you might need to add additional defines to
runtime/utrace_compatibility.h since the itrace code uses parts of
utrace that the task_finder layer doesn't use.

Let me know if you need help with this or additional information.

-- 
David Smith
dsmith@redhat.com
Red Hat
http://www.redhat.com
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