Merge remote-tracking branch 'remotes/stefanha/tags/tracing-pull-request' into staging

Tracing pull request

* remotes/stefanha/tags/tracing-pull-request:
  virtio-rng: add some trace events
  trace: add some tcg tracing support
  trace: teach lttng backend to use format strings
  trace: [tcg] Include TCG-tracing header on all targets
  trace: [tcg] Include event definitions in "trace.h"
  trace: [tcg] Generate TCG tracing routines
  trace: [tcg] Include TCG-tracing helpers
  trace: [tcg] Define TCG tracing helper routine wrappers
  trace: [tcg] Define TCG tracing helper routines
  trace: [tcg] Declare TCG tracing helper routines
  trace: [tcg] Add 'tcg' event property
  trace: [tcg] Argument type transformation machinery
  trace: [tcg] Argument type transformation rules
  trace: [tcg] Add documentation
  trace: install simpletrace SystemTap tapset
  simpletrace: add simpletrace.py --no-header option
  trace: add tracetool simpletrace_stap format
  trace: extract stap_escape() function for reuse

Conflicts:
	Makefile.objs

1 files changed, 71 insertions, 0 deletions

diff --git a/scripts/tracetool/format/simpletrace_stap.py b/scripts/tracetool/format/simpletrace_stap.py
new file mode 100644
index 0000000000..7e44bc1811
--- /dev/null
+++ b/scripts/tracetool/format/simpletrace_stap.py
@@ -0,0 +1,71 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+"""
+Generate .stp file that outputs simpletrace binary traces (DTrace with SystemTAP only).
+"""
+
+__author__     = "Stefan Hajnoczi <redhat.com>"
+__copyright__  = "Copyright (C) 2014, Red Hat, Inc."
+__license__    = "GPL version 2 or (at your option) any later version"
+
+__maintainer__ = "Stefan Hajnoczi"
+__email__      = "stefanha@redhat.com"
+
+
+from tracetool import out
+from tracetool.backend.dtrace import binary, probeprefix
+from tracetool.backend.simple import is_string
+from tracetool.format.stap import stap_escape
+
+
+def generate(events, backend):
+    out('/* This file is autogenerated by tracetool, do not edit. */',
+        '')
+
+    for event_id, e in enumerate(events):
+        if 'disable' in e.properties:
+            continue
+
+        out('probe %(probeprefix)s.simpletrace.%(name)s = %(probeprefix)s.%(name)s ?',
+            '{',
+            probeprefix=probeprefix(),
+            name=e.name)
+
+        # Calculate record size
+        sizes = ['24'] # sizeof(TraceRecord)
+        for type_, name in e.args:
+            name = stap_escape(name)
+            if is_string(type_):
+                out('    try {',
+                    '        arg%(name)s_str = %(name)s ? user_string_n(%(name)s, 512) : "<null>"',
+                    '    } catch {}',
+                    '    arg%(name)s_len = strlen(arg%(name)s_str)',
+                    name=name)
+                sizes.append('4 + arg%s_len' % name)
+            else:
+                sizes.append('8')
+        sizestr = ' + '.join(sizes)
+
+        # Generate format string and value pairs for record header and arguments
+        fields = [('8b', str(event_id)),
+                  ('8b', 'gettimeofday_ns()'),
+                  ('4b', sizestr),
+                  ('4b', 'pid()')]
+        for type_, name in e.args:
+            name = stap_escape(name)
+            if is_string(type_):
+                fields.extend([('4b', 'arg%s_len' % name),
+                               ('.*s', 'arg%s_len, arg%s_str' % (name, name))])
+            else:
+                fields.append(('8b', name))
+
+        # Emit the entire record in a single SystemTap printf()
+        fmt_str = '%'.join(fmt for fmt, _ in fields)
+        arg_str = ', '.join(arg for _, arg in fields)
+        out('    printf("%%%(fmt_str)s", %(arg_str)s)',
+            fmt_str=fmt_str, arg_str=arg_str)
+
+        out('}')
+
+    out()