linux-next: add utrace tree

[tytso at mit.edu]

On Sat, Jan 23, 2010 at 09:04:56PM -0800, Linus Torvalds wrote:
> > The killer app for this will be the ability to delete thousands of
> > lines of code from GDB, strace, and all the various other tools that
> > have to painfully work around the major interface gotchas of ptrace(),
> > while at the same time making their handling of complex processes much
> > more robust.
> 
> No. There is absolutely _no_ reason to believe that gdb et al would ever 
> delete the ptrace interfaces anyway. 

More to the point, gdb *couldn't* use utrace, because utrace only
exports a kernel API; not a syscall interface.  And if the Red Hat
Toolchain folks are thinking about encouraging gdb to start creating
out-of-tree kernel modules, so that (a) gdb requires root privs, and
(b) gdb is as (un)stable as SystemTap with respect to development
kernels by making it dependent on internal kernel API's, the Red Hat
Toolchain group needs to be smacked upside the head...

	  	      	    	    	   - Ted