If TRACE_INCLDUE_FILE is defined, <trace/events/TRACE_INCLUDE_FILE.h>
will be included and compiled, otherwise it will be
<trace/events/TRACE_SYSTEM.h>

So TRACE_SYSTEM should be defined outside of #if proctection,
just like TRACE_INCLUDE_FILE.

Imaging this scenario:

 #include <trace/events/foo.h>
    -> TRACE_SYSTEM == foo
 ...
 #include <trace/events/bar.h>
    -> TRACE_SYSTEM == bar
 ...
 #define CREATE_TRACE_POINTS
 #include <trace/events/foo.h>
    -> TRACE_SYSTEM == bar !!!

and then bar.h will be included and compiled.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A5A9CF1.2010007@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch adds the ability to trace various aspects of the GFS2
filesystem. The trace points are divided into three groups,
glocks, logging and bmap. These points have been chosen because
they allow inspection of the major internal functions of GFS2
and they are also generic enough that they are unlikely to need
any major changes as the filesystem evolves.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>