Move kern_ctf to the dtrace module?

[Paul Goyette <paul%whooppee.com@localhost>]

Currently, if you include KDTRACE_HOOKS in your kernel, we automatically 
include src/sys/kern/kern_ctf.[co] in the resulting kernel.

kern_ctf defines only one global symbol, mod_ctf_get(), according to the 
generated netbsd.map file, and there are no references anywhere else in 
the kernel to this routine;  the only reference is within the sub-module 
dtrace_fbt.kmod

I would like to suggest that kern_ctf be removed from the kernel, and 
added to the dtrace_fbt module.  And, since kern_ctf references stuff in 
net/zlib.c, the dtrace_fbt module should depend on zlib module.  And 
finally, the ktrace_hooks dependency can be removed from the zlib.c line 
in net/files.net

The bottom line is that zlib code won't be included in kernels that 
don't need it, yet will still be available when using dtrace (which is 
only available as a module).


If I don't see any significant objections, I'll post diffs in a day or 
so before making any commits.



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| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:      |
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