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>

scripts/tracetool.py

@@ -137,10 +137,12 @@ def main(args):
         if probe_prefix is None:
             probe_prefix = ".".join(["qemu", target_type, target_name])
 
-    if len(args) != 1:
+    if len(args) < 1:
         error_opt("missing trace-events filepath")
-    with open(args[0], "r") as fh:
-        events = tracetool.read_events(fh)
+    events = []
+    for arg in args:
+        with open(arg, "r") as fh:
+            events.extend(tracetool.read_events(fh))
 
     try:
         tracetool.generate(events, arg_group, arg_format, arg_backends,

scripts/tracetool/backend/dtrace.py

@@ -36,7 +36,12 @@ def binary():
 
 
 def generate_h_begin(events, group):
-    out('#include "trace/generated-tracers-dtrace.h"',
+    if group == "root":
+        header = "trace-dtrace-root.h"
+    else:
+        header = "trace-dtrace.h"
+
+    out('#include "%s"' % header,
         '')
 
 

scripts/tracetool/backend/simple.py

@@ -44,7 +44,6 @@ def generate_h(event, group):
 
 def generate_c_begin(events, group):
     out('#include "qemu/osdep.h"',
-        '#include "trace.h"',
         '#include "trace/control.h"',
         '#include "trace/simple.h"',
         '')

scripts/tracetool/backend/ust.py

@@ -20,8 +20,13 @@ PUBLIC = True
 
 
 def generate_h_begin(events, group):
+    if group == "root":
+        header = "trace-ust-root.h"
+    else:
+        header = "trace-ust.h"
+
     out('#include <lttng/tracepoint.h>',
-        '#include "trace/generated-ust-provider.h"',
+        '#include "%s"' % header,
         '')
 
 

scripts/tracetool/format/c.py

@@ -20,10 +20,15 @@ def generate(events, backend, group):
     active_events = [e for e in events
                      if "disable" not in e.properties]
 
+    if group == "root":
+        header = "trace-root.h"
+    else:
+        header = "trace.h"
+
     out('/* This file is autogenerated by tracetool, do not edit. */',
         '',
         '#include "qemu/osdep.h"',
-        '#include "trace.h"',
+        '#include "%s"' % header,
         '')
 
     for e in events:

scripts/tracetool/format/tcg_h.py

@@ -28,13 +28,17 @@ def vcpu_transform_args(args):
 
 
 def generate(events, backend, group):
+    if group == "root":
+        header = "trace-root.h"
+    else:
+        header = "trace.h"
+
     out('/* This file is autogenerated by tracetool, do not edit. */',
         '/* You must include this file after the inclusion of helper.h */',
         '',
         '#ifndef TRACE_%s_GENERATED_TCG_TRACERS_H' % group.upper(),
         '#define TRACE_%s_GENERATED_TCG_TRACERS_H' % group.upper(),
         '',
-        '#include "trace.h"',
         '#include "exec/helper-proto.h"',
         '',
         )

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"',
         '',
         )

scripts/tracetool/format/ust_events_c.py

@@ -32,4 +32,4 @@ def generate(events, backend, group):
         ' */',
         '#pragma GCC diagnostic ignored "-Wredundant-decls"',
         '',
-        '#include "generated-ust-provider.h"')
+        '#include "trace-ust-all.h"')

scripts/tracetool/format/ust_events_h.py

@@ -20,13 +20,18 @@ def generate(events, backend, group):
     events = [e for e in events
               if "disabled" not in e.properties]
 
+    if group == "all":
+        include = "trace-ust-all.h"
+    else:
+        include = "trace-ust.h"
+
     out('/* This file is autogenerated by tracetool, do not edit. */',
         '',
         '#undef TRACEPOINT_PROVIDER',
         '#define TRACEPOINT_PROVIDER qemu',
         '',
         '#undef TRACEPOINT_INCLUDE_FILE',
-        '#define TRACEPOINT_INCLUDE_FILE ./generated-ust-provider.h',
+        '#define TRACEPOINT_INCLUDE_FILE ./%s' % include,
         '',
         '#if !defined (TRACE_%s_GENERATED_UST_H) || \\'  % group.upper(),
         '     defined(TRACEPOINT_HEADER_MULTI_READ)',