trace: switch to modular code generation for sub-directories

Introduce rules in the top level Makefile that are able to generate
trace.[ch] files in every subdirectory which has a trace-events file.

The top level directory is handled specially, so instead of creating
trace.h, it creates trace-root.h. This allows sub-directories to
include the top level trace-root.h file, without ambiguity wrt to
the trace.g file in the current sub-dir.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170125161417.31949-7-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/scripts/tracetool/format/tcg_helper_c.py b/scripts/tracetool/format/tcg_helper_c.py
index cc26e03008..7dccd8c5ec 100644
--- a/scripts/tracetool/format/tcg_helper_c.py
+++ b/scripts/tracetool/format/tcg_helper_c.py
@@ -41,6 +41,11 @@ def vcpu_transform_args(args, mode):
 
 
 def generate(events, backend, group):
+    if group == "root":
+        header = "trace-root.h"
+    else:
+        header = "trace.h"
+
     events = [e for e in events
               if "disable" not in e.properties]
 
@@ -49,7 +54,6 @@ def generate(events, backend, group):
         '#include "qemu/osdep.h"',
         '#include "qemu-common.h"',
         '#include "cpu.h"',
-        '#include "trace.h"',
         '#include "exec/helper-proto.h"',
         '',
         )