[PATCH] add success/failure indication to RCU torture test

One issue with the RCU torture test is that the current error flagging can
be lost in dmesg.  This patch adds a "SUCCESS"/"FAILURE" string to the line
that flags the end of the test, where it can easily be seen with "dmesg |
tail" at the end of the test.  Also adds tests of architecture-specific
memory barriers -- or, more likely, of the RCU torture test itself.

Cc: <vatsa@in.ibm.com>
Signed-off-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>