Daniel P. Berrange 81dee729c1 Avoid all systemtap reserved words
Over time various systemtap reserved words have been blacklisted
in the trace backend generator. The list is not complete though,
so there is continued risk of problems in the future. Preempt
such problems by specifying the full list of systemtap keywords
listed in its parser as identified here:

  http://sourceware.org/ml/systemtap/2012-q4/msg00157.html

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2012-11-16 13:12:13 +01:00

107 lines
2.4 KiB
Python

#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
DTrace/SystemTAP backend.
"""
__author__ = "Lluís Vilanova <vilanova@ac.upc.edu>"
__copyright__ = "Copyright 2012, Lluís Vilanova <vilanova@ac.upc.edu>"
__license__ = "GPL version 2 or (at your option) any later version"
__maintainer__ = "Stefan Hajnoczi"
__email__ = "stefanha@linux.vnet.ibm.com"
from tracetool import out
PROBEPREFIX = None
def _probeprefix():
if PROBEPREFIX is None:
raise ValueError("you must set PROBEPREFIX")
return PROBEPREFIX
BINARY = None
def _binary():
if BINARY is None:
raise ValueError("you must set BINARY")
return BINARY
def c(events):
pass
def h(events):
out('#include "trace-dtrace.h"',
'')
for e in events:
out('static inline void trace_%(name)s(%(args)s) {',
' QEMU_%(uppername)s(%(argnames)s);',
'}',
name = e.name,
args = e.args,
uppername = e.name.upper(),
argnames = ", ".join(e.args.names()),
)
def d(events):
out('provider qemu {')
for e in events:
args = str(e.args)
# DTrace provider syntax expects foo() for empty
# params, not foo(void)
if args == 'void':
args = ''
# Define prototype for probe arguments
out('',
'probe %(name)s(%(args)s);',
name = e.name,
args = args,
)
out('',
'};')
# Technically 'self' is not used by systemtap yet, but
# they recommended we keep it in the reserved list anyway
RESERVED_WORDS = (
'break', 'catch', 'continue', 'delete', 'else', 'for',
'foreach', 'function', 'global', 'if', 'in', 'limit',
'long', 'next', 'probe', 'return', 'self', 'string',
'try', 'while'
)
def stap(events):
for e in events:
# Define prototype for probe arguments
out('probe %(probeprefix)s.%(name)s = process("%(binary)s").mark("%(name)s")',
'{',
probeprefix = _probeprefix(),
name = e.name,
binary = _binary(),
)
i = 1
if len(e.args) > 0:
for name in e.args.names():
# Append underscore to reserved keywords
if name in RESERVED_WORDS:
name += '_'
out(' %s = $arg%d;' % (name, i))
i += 1
out('}')
out()