1#!/usr/bin/env python 2# -*- coding: utf-8 -*- 3 4""" 5Machinery for generating tracing-related intermediate files. 6""" 7 8__author__ = "Lluís Vilanova <vilanova@ac.upc.edu>" 9__copyright__ = "Copyright 2012-2016, Lluís Vilanova <vilanova@ac.upc.edu>" 10__license__ = "GPL version 2 or (at your option) any later version" 11 12__maintainer__ = "Stefan Hajnoczi" 13__email__ = "stefanha@linux.vnet.ibm.com" 14 15 16import re 17import sys 18import weakref 19 20import tracetool.format 21import tracetool.backend 22import tracetool.transform 23 24 25def error_write(*lines): 26 """Write a set of error lines.""" 27 sys.stderr.writelines("\n".join(lines) + "\n") 28 29def error(*lines): 30 """Write a set of error lines and exit.""" 31 error_write(*lines) 32 sys.exit(1) 33 34 35def out(*lines, **kwargs): 36 """Write a set of output lines. 37 38 You can use kwargs as a shorthand for mapping variables when formating all 39 the strings in lines. 40 """ 41 lines = [ l % kwargs for l in lines ] 42 sys.stdout.writelines("\n".join(lines) + "\n") 43 44 45class Arguments: 46 """Event arguments description.""" 47 48 def __init__(self, args): 49 """ 50 Parameters 51 ---------- 52 args : 53 List of (type, name) tuples or Arguments objects. 54 """ 55 self._args = [] 56 for arg in args: 57 if isinstance(arg, Arguments): 58 self._args.extend(arg._args) 59 else: 60 self._args.append(arg) 61 62 def copy(self): 63 """Create a new copy.""" 64 return Arguments(list(self._args)) 65 66 @staticmethod 67 def build(arg_str): 68 """Build and Arguments instance from an argument string. 69 70 Parameters 71 ---------- 72 arg_str : str 73 String describing the event arguments. 74 """ 75 res = [] 76 for arg in arg_str.split(","): 77 arg = arg.strip() 78 if arg == 'void': 79 continue 80 81 if '*' in arg: 82 arg_type, identifier = arg.rsplit('*', 1) 83 arg_type += '*' 84 identifier = identifier.strip() 85 else: 86 arg_type, identifier = arg.rsplit(None, 1) 87 88 res.append((arg_type, identifier)) 89 return Arguments(res) 90 91 def __getitem__(self, index): 92 if isinstance(index, slice): 93 return Arguments(self._args[index]) 94 else: 95 return self._args[index] 96 97 def __iter__(self): 98 """Iterate over the (type, name) pairs.""" 99 return iter(self._args) 100 101 def __len__(self): 102 """Number of arguments.""" 103 return len(self._args) 104 105 def __str__(self): 106 """String suitable for declaring function arguments.""" 107 if len(self._args) == 0: 108 return "void" 109 else: 110 return ", ".join([ " ".join([t, n]) for t,n in self._args ]) 111 112 def __repr__(self): 113 """Evaluable string representation for this object.""" 114 return "Arguments(\"%s\")" % str(self) 115 116 def names(self): 117 """List of argument names.""" 118 return [ name for _, name in self._args ] 119 120 def types(self): 121 """List of argument types.""" 122 return [ type_ for type_, _ in self._args ] 123 124 def transform(self, *trans): 125 """Return a new Arguments instance with transformed types. 126 127 The types in the resulting Arguments instance are transformed according 128 to tracetool.transform.transform_type. 129 """ 130 res = [] 131 for type_, name in self._args: 132 res.append((tracetool.transform.transform_type(type_, *trans), 133 name)) 134 return Arguments(res) 135 136 137class Event(object): 138 """Event description. 139 140 Attributes 141 ---------- 142 name : str 143 The event name. 144 fmt : str 145 The event format string. 146 properties : set(str) 147 Properties of the event. 148 args : Arguments 149 The event arguments. 150 151 """ 152 153 _CRE = re.compile("((?P<props>[\w\s]+)\s+)?" 154 "(?P<name>\w+)" 155 "\((?P<args>[^)]*)\)" 156 "\s*" 157 "(?:(?:(?P<fmt_trans>\".+),)?\s*(?P<fmt>\".+))?" 158 "\s*") 159 160 _VALID_PROPS = set(["disable", "tcg", "tcg-trans", "tcg-exec"]) 161 162 def __init__(self, name, props, fmt, args, orig=None): 163 """ 164 Parameters 165 ---------- 166 name : string 167 Event name. 168 props : list of str 169 Property names. 170 fmt : str, list of str 171 Event printing format (or formats). 172 args : Arguments 173 Event arguments. 174 orig : Event or None 175 Original Event before transformation. 176 177 """ 178 self.name = name 179 self.properties = props 180 self.fmt = fmt 181 self.args = args 182 183 if orig is None: 184 self.original = weakref.ref(self) 185 else: 186 self.original = orig 187 188 unknown_props = set(self.properties) - self._VALID_PROPS 189 if len(unknown_props) > 0: 190 raise ValueError("Unknown properties: %s" 191 % ", ".join(unknown_props)) 192 assert isinstance(self.fmt, str) or len(self.fmt) == 2 193 194 def copy(self): 195 """Create a new copy.""" 196 return Event(self.name, list(self.properties), self.fmt, 197 self.args.copy(), self) 198 199 @staticmethod 200 def build(line_str): 201 """Build an Event instance from a string. 202 203 Parameters 204 ---------- 205 line_str : str 206 Line describing the event. 207 """ 208 m = Event._CRE.match(line_str) 209 assert m is not None 210 groups = m.groupdict('') 211 212 name = groups["name"] 213 props = groups["props"].split() 214 fmt = groups["fmt"] 215 fmt_trans = groups["fmt_trans"] 216 if len(fmt_trans) > 0: 217 fmt = [fmt_trans, fmt] 218 args = Arguments.build(groups["args"]) 219 220 if "tcg-trans" in props: 221 raise ValueError("Invalid property 'tcg-trans'") 222 if "tcg-exec" in props: 223 raise ValueError("Invalid property 'tcg-exec'") 224 if "tcg" not in props and not isinstance(fmt, str): 225 raise ValueError("Only events with 'tcg' property can have two formats") 226 if "tcg" in props and isinstance(fmt, str): 227 raise ValueError("Events with 'tcg' property must have two formats") 228 229 return Event(name, props, fmt, args) 230 231 def __repr__(self): 232 """Evaluable string representation for this object.""" 233 if isinstance(self.fmt, str): 234 fmt = self.fmt 235 else: 236 fmt = "%s, %s" % (self.fmt[0], self.fmt[1]) 237 return "Event('%s %s(%s) %s')" % (" ".join(self.properties), 238 self.name, 239 self.args, 240 fmt) 241 242 _FMT = re.compile("(%[\d\.]*\w+|%.*PRI\S+)") 243 244 def formats(self): 245 """List of argument print formats.""" 246 assert not isinstance(self.fmt, list) 247 return self._FMT.findall(self.fmt) 248 249 QEMU_TRACE = "trace_%(name)s" 250 QEMU_TRACE_TCG = QEMU_TRACE + "_tcg" 251 252 def api(self, fmt=None): 253 if fmt is None: 254 fmt = Event.QEMU_TRACE 255 return fmt % {"name": self.name} 256 257 def transform(self, *trans): 258 """Return a new Event with transformed Arguments.""" 259 return Event(self.name, 260 list(self.properties), 261 self.fmt, 262 self.args.transform(*trans), 263 self) 264 265 266def _read_events(fobj): 267 events = [] 268 for line in fobj: 269 if not line.strip(): 270 continue 271 if line.lstrip().startswith('#'): 272 continue 273 274 event = Event.build(line) 275 276 # transform TCG-enabled events 277 if "tcg" not in event.properties: 278 events.append(event) 279 else: 280 event_trans = event.copy() 281 event_trans.name += "_trans" 282 event_trans.properties += ["tcg-trans"] 283 event_trans.fmt = event.fmt[0] 284 args_trans = [] 285 for atrans, aorig in zip( 286 event_trans.transform(tracetool.transform.TCG_2_HOST).args, 287 event.args): 288 if atrans == aorig: 289 args_trans.append(atrans) 290 event_trans.args = Arguments(args_trans) 291 292 event_exec = event.copy() 293 event_exec.name += "_exec" 294 event_exec.properties += ["tcg-exec"] 295 event_exec.fmt = event.fmt[1] 296 event_exec.args = event_exec.args.transform(tracetool.transform.TCG_2_HOST) 297 298 new_event = [event_trans, event_exec] 299 event.event_trans, event.event_exec = new_event 300 301 events.extend(new_event) 302 303 return events 304 305 306class TracetoolError (Exception): 307 """Exception for calls to generate.""" 308 pass 309 310 311def try_import(mod_name, attr_name=None, attr_default=None): 312 """Try to import a module and get an attribute from it. 313 314 Parameters 315 ---------- 316 mod_name : str 317 Module name. 318 attr_name : str, optional 319 Name of an attribute in the module. 320 attr_default : optional 321 Default value if the attribute does not exist in the module. 322 323 Returns 324 ------- 325 A pair indicating whether the module could be imported and the module or 326 object or attribute value. 327 """ 328 try: 329 module = __import__(mod_name, globals(), locals(), ["__package__"]) 330 if attr_name is None: 331 return True, module 332 return True, getattr(module, str(attr_name), attr_default) 333 except ImportError: 334 return False, None 335 336 337def generate(fevents, format, backends, 338 binary=None, probe_prefix=None): 339 """Generate the output for the given (format, backends) pair. 340 341 Parameters 342 ---------- 343 fevents : file 344 Event description file. 345 format : str 346 Output format name. 347 backends : list 348 Output backend names. 349 binary : str or None 350 See tracetool.backend.dtrace.BINARY. 351 probe_prefix : str or None 352 See tracetool.backend.dtrace.PROBEPREFIX. 353 """ 354 # fix strange python error (UnboundLocalError tracetool) 355 import tracetool 356 357 format = str(format) 358 if len(format) is 0: 359 raise TracetoolError("format not set") 360 if not tracetool.format.exists(format): 361 raise TracetoolError("unknown format: %s" % format) 362 363 if len(backends) is 0: 364 raise TracetoolError("no backends specified") 365 for backend in backends: 366 if not tracetool.backend.exists(backend): 367 raise TracetoolError("unknown backend: %s" % backend) 368 backend = tracetool.backend.Wrapper(backends, format) 369 370 import tracetool.backend.dtrace 371 tracetool.backend.dtrace.BINARY = binary 372 tracetool.backend.dtrace.PROBEPREFIX = probe_prefix 373 374 events = _read_events(fevents) 375 376 tracetool.format.generate(events, format, backend) 377