Merge tag 'net-pull-request' of https://github.com/jasowang/qemu into staging
[qemu.git] / scripts / tracetool / __init__.py
1 # -*- coding: utf-8 -*-
2
3 """
4 Machinery for generating tracing-related intermediate files.
5 """
6
7 __author__ = "Lluís Vilanova <vilanova@ac.upc.edu>"
8 __copyright__ = "Copyright 2012-2017, Lluís Vilanova <vilanova@ac.upc.edu>"
9 __license__ = "GPL version 2 or (at your option) any later version"
10
11 __maintainer__ = "Stefan Hajnoczi"
12 __email__ = "stefanha@redhat.com"
13
14
15 import re
16 import sys
17 import weakref
18
19 import tracetool.format
20 import tracetool.backend
21 import tracetool.transform
22
23
24 def error_write(*lines):
25 """Write a set of error lines."""
26 sys.stderr.writelines("\n".join(lines) + "\n")
27
28 def error(*lines):
29 """Write a set of error lines and exit."""
30 error_write(*lines)
31 sys.exit(1)
32
33
34 out_lineno = 1
35 out_filename = '<none>'
36 out_fobj = sys.stdout
37
38 def out_open(filename):
39 global out_filename, out_fobj
40 out_filename = filename
41 out_fobj = open(filename, 'wt')
42
43 def out(*lines, **kwargs):
44 """Write a set of output lines.
45
46 You can use kwargs as a shorthand for mapping variables when formatting all
47 the strings in lines.
48
49 The 'out_lineno' kwarg is automatically added to reflect the current output
50 file line number. The 'out_next_lineno' kwarg is also automatically added
51 with the next output line number. The 'out_filename' kwarg is automatically
52 added with the output filename.
53 """
54 global out_lineno
55 output = []
56 for l in lines:
57 kwargs['out_lineno'] = out_lineno
58 kwargs['out_next_lineno'] = out_lineno + 1
59 kwargs['out_filename'] = out_filename
60 output.append(l % kwargs)
61 out_lineno += 1
62
63 out_fobj.writelines("\n".join(output) + "\n")
64
65 # We only want to allow standard C types or fixed sized
66 # integer types. We don't want QEMU specific types
67 # as we can't assume trace backends can resolve all the
68 # typedefs
69 ALLOWED_TYPES = [
70 "int",
71 "long",
72 "short",
73 "char",
74 "bool",
75 "unsigned",
76 "signed",
77 "int8_t",
78 "uint8_t",
79 "int16_t",
80 "uint16_t",
81 "int32_t",
82 "uint32_t",
83 "int64_t",
84 "uint64_t",
85 "void",
86 "size_t",
87 "ssize_t",
88 "uintptr_t",
89 "ptrdiff_t",
90 ]
91
92 def validate_type(name):
93 bits = name.split(" ")
94 for bit in bits:
95 bit = re.sub("\*", "", bit)
96 if bit == "":
97 continue
98 if bit == "const":
99 continue
100 if bit not in ALLOWED_TYPES:
101 raise ValueError("Argument type '%s' is not allowed. "
102 "Only standard C types and fixed size integer "
103 "types should be used. struct, union, and "
104 "other complex pointer types should be "
105 "declared as 'void *'" % name)
106
107 class Arguments:
108 """Event arguments description."""
109
110 def __init__(self, args):
111 """
112 Parameters
113 ----------
114 args :
115 List of (type, name) tuples or Arguments objects.
116 """
117 self._args = []
118 for arg in args:
119 if isinstance(arg, Arguments):
120 self._args.extend(arg._args)
121 else:
122 self._args.append(arg)
123
124 def copy(self):
125 """Create a new copy."""
126 return Arguments(list(self._args))
127
128 @staticmethod
129 def build(arg_str):
130 """Build and Arguments instance from an argument string.
131
132 Parameters
133 ----------
134 arg_str : str
135 String describing the event arguments.
136 """
137 res = []
138 for arg in arg_str.split(","):
139 arg = arg.strip()
140 if not arg:
141 raise ValueError("Empty argument (did you forget to use 'void'?)")
142 if arg == 'void':
143 continue
144
145 if '*' in arg:
146 arg_type, identifier = arg.rsplit('*', 1)
147 arg_type += '*'
148 identifier = identifier.strip()
149 else:
150 arg_type, identifier = arg.rsplit(None, 1)
151
152 validate_type(arg_type)
153 res.append((arg_type, identifier))
154 return Arguments(res)
155
156 def __getitem__(self, index):
157 if isinstance(index, slice):
158 return Arguments(self._args[index])
159 else:
160 return self._args[index]
161
162 def __iter__(self):
163 """Iterate over the (type, name) pairs."""
164 return iter(self._args)
165
166 def __len__(self):
167 """Number of arguments."""
168 return len(self._args)
169
170 def __str__(self):
171 """String suitable for declaring function arguments."""
172 if len(self._args) == 0:
173 return "void"
174 else:
175 return ", ".join([ " ".join([t, n]) for t,n in self._args ])
176
177 def __repr__(self):
178 """Evaluable string representation for this object."""
179 return "Arguments(\"%s\")" % str(self)
180
181 def names(self):
182 """List of argument names."""
183 return [ name for _, name in self._args ]
184
185 def types(self):
186 """List of argument types."""
187 return [ type_ for type_, _ in self._args ]
188
189 def casted(self):
190 """List of argument names casted to their type."""
191 return ["(%s)%s" % (type_, name) for type_, name in self._args]
192
193 def transform(self, *trans):
194 """Return a new Arguments instance with transformed types.
195
196 The types in the resulting Arguments instance are transformed according
197 to tracetool.transform.transform_type.
198 """
199 res = []
200 for type_, name in self._args:
201 res.append((tracetool.transform.transform_type(type_, *trans),
202 name))
203 return Arguments(res)
204
205
206 class Event(object):
207 """Event description.
208
209 Attributes
210 ----------
211 name : str
212 The event name.
213 fmt : str
214 The event format string.
215 properties : set(str)
216 Properties of the event.
217 args : Arguments
218 The event arguments.
219 lineno : int
220 The line number in the input file.
221 filename : str
222 The path to the input file.
223
224 """
225
226 _CRE = re.compile("((?P<props>[\w\s]+)\s+)?"
227 "(?P<name>\w+)"
228 "\((?P<args>[^)]*)\)"
229 "\s*"
230 "(?:(?:(?P<fmt_trans>\".+),)?\s*(?P<fmt>\".+))?"
231 "\s*")
232
233 _VALID_PROPS = set(["disable", "vcpu"])
234
235 def __init__(self, name, props, fmt, args, lineno, filename, orig=None,
236 event_trans=None, event_exec=None):
237 """
238 Parameters
239 ----------
240 name : string
241 Event name.
242 props : list of str
243 Property names.
244 fmt : str, list of str
245 Event printing format string(s).
246 args : Arguments
247 Event arguments.
248 lineno : int
249 The line number in the input file.
250 filename : str
251 The path to the input file.
252 orig : Event or None
253 Original Event before transformation/generation.
254 event_trans : Event or None
255 Generated translation-time event ("tcg" property).
256 event_exec : Event or None
257 Generated execution-time event ("tcg" property).
258
259 """
260 self.name = name
261 self.properties = props
262 self.fmt = fmt
263 self.args = args
264 self.lineno = int(lineno)
265 self.filename = str(filename)
266 self.event_trans = event_trans
267 self.event_exec = event_exec
268
269 if len(args) > 10:
270 raise ValueError("Event '%s' has more than maximum permitted "
271 "argument count" % name)
272
273 if orig is None:
274 self.original = weakref.ref(self)
275 else:
276 self.original = orig
277
278 unknown_props = set(self.properties) - self._VALID_PROPS
279 if len(unknown_props) > 0:
280 raise ValueError("Unknown properties: %s"
281 % ", ".join(unknown_props))
282 assert isinstance(self.fmt, str) or len(self.fmt) == 2
283
284 def copy(self):
285 """Create a new copy."""
286 return Event(self.name, list(self.properties), self.fmt,
287 self.args.copy(), self.lineno, self.filename,
288 self, self.event_trans, self.event_exec)
289
290 @staticmethod
291 def build(line_str, lineno, filename):
292 """Build an Event instance from a string.
293
294 Parameters
295 ----------
296 line_str : str
297 Line describing the event.
298 lineno : int
299 Line number in input file.
300 filename : str
301 Path to input file.
302 """
303 m = Event._CRE.match(line_str)
304 assert m is not None
305 groups = m.groupdict('')
306
307 name = groups["name"]
308 props = groups["props"].split()
309 fmt = groups["fmt"]
310 fmt_trans = groups["fmt_trans"]
311 if fmt.find("%m") != -1 or fmt_trans.find("%m") != -1:
312 raise ValueError("Event format '%m' is forbidden, pass the error "
313 "as an explicit trace argument")
314 if fmt.endswith(r'\n"'):
315 raise ValueError("Event format must not end with a newline "
316 "character")
317
318 if len(fmt_trans) > 0:
319 fmt = [fmt_trans, fmt]
320 args = Arguments.build(groups["args"])
321
322 event = Event(name, props, fmt, args, lineno, filename)
323
324 # add implicit arguments when using the 'vcpu' property
325 import tracetool.vcpu
326 event = tracetool.vcpu.transform_event(event)
327
328 return event
329
330 def __repr__(self):
331 """Evaluable string representation for this object."""
332 if isinstance(self.fmt, str):
333 fmt = self.fmt
334 else:
335 fmt = "%s, %s" % (self.fmt[0], self.fmt[1])
336 return "Event('%s %s(%s) %s')" % (" ".join(self.properties),
337 self.name,
338 self.args,
339 fmt)
340 # Star matching on PRI is dangerous as one might have multiple
341 # arguments with that format, hence the non-greedy version of it.
342 _FMT = re.compile("(%[\d\.]*\w+|%.*?PRI\S+)")
343
344 def formats(self):
345 """List conversion specifiers in the argument print format string."""
346 assert not isinstance(self.fmt, list)
347 return self._FMT.findall(self.fmt)
348
349 QEMU_TRACE = "trace_%(name)s"
350 QEMU_TRACE_NOCHECK = "_nocheck__" + QEMU_TRACE
351 QEMU_TRACE_TCG = QEMU_TRACE + "_tcg"
352 QEMU_DSTATE = "_TRACE_%(NAME)s_DSTATE"
353 QEMU_BACKEND_DSTATE = "TRACE_%(NAME)s_BACKEND_DSTATE"
354 QEMU_EVENT = "_TRACE_%(NAME)s_EVENT"
355
356 def api(self, fmt=None):
357 if fmt is None:
358 fmt = Event.QEMU_TRACE
359 return fmt % {"name": self.name, "NAME": self.name.upper()}
360
361 def transform(self, *trans):
362 """Return a new Event with transformed Arguments."""
363 return Event(self.name,
364 list(self.properties),
365 self.fmt,
366 self.args.transform(*trans),
367 self.lineno,
368 self.filename,
369 self)
370
371
372 def read_events(fobj, fname):
373 """Generate the output for the given (format, backends) pair.
374
375 Parameters
376 ----------
377 fobj : file
378 Event description file.
379 fname : str
380 Name of event file
381
382 Returns a list of Event objects
383 """
384
385 events = []
386 for lineno, line in enumerate(fobj, 1):
387 if line[-1] != '\n':
388 raise ValueError("%s does not end with a new line" % fname)
389 if not line.strip():
390 continue
391 if line.lstrip().startswith('#'):
392 continue
393
394 try:
395 event = Event.build(line, lineno, fname)
396 except ValueError as e:
397 arg0 = 'Error at %s:%d: %s' % (fname, lineno, e.args[0])
398 e.args = (arg0,) + e.args[1:]
399 raise
400
401 events.append(event)
402
403 return events
404
405
406 class TracetoolError (Exception):
407 """Exception for calls to generate."""
408 pass
409
410
411 def try_import(mod_name, attr_name=None, attr_default=None):
412 """Try to import a module and get an attribute from it.
413
414 Parameters
415 ----------
416 mod_name : str
417 Module name.
418 attr_name : str, optional
419 Name of an attribute in the module.
420 attr_default : optional
421 Default value if the attribute does not exist in the module.
422
423 Returns
424 -------
425 A pair indicating whether the module could be imported and the module or
426 object or attribute value.
427 """
428 try:
429 module = __import__(mod_name, globals(), locals(), ["__package__"])
430 if attr_name is None:
431 return True, module
432 return True, getattr(module, str(attr_name), attr_default)
433 except ImportError:
434 return False, None
435
436
437 def generate(events, group, format, backends,
438 binary=None, probe_prefix=None):
439 """Generate the output for the given (format, backends) pair.
440
441 Parameters
442 ----------
443 events : list
444 list of Event objects to generate for
445 group: str
446 Name of the tracing group
447 format : str
448 Output format name.
449 backends : list
450 Output backend names.
451 binary : str or None
452 See tracetool.backend.dtrace.BINARY.
453 probe_prefix : str or None
454 See tracetool.backend.dtrace.PROBEPREFIX.
455 """
456 # fix strange python error (UnboundLocalError tracetool)
457 import tracetool
458
459 format = str(format)
460 if len(format) == 0:
461 raise TracetoolError("format not set")
462 if not tracetool.format.exists(format):
463 raise TracetoolError("unknown format: %s" % format)
464
465 if len(backends) == 0:
466 raise TracetoolError("no backends specified")
467 for backend in backends:
468 if not tracetool.backend.exists(backend):
469 raise TracetoolError("unknown backend: %s" % backend)
470 backend = tracetool.backend.Wrapper(backends, format)
471
472 import tracetool.backend.dtrace
473 tracetool.backend.dtrace.BINARY = binary
474 tracetool.backend.dtrace.PROBEPREFIX = probe_prefix
475
476 tracetool.format.generate(events, format, backend, group)