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 2012-2014, 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. 54 """ 55 self._args = args 56 57 def copy(self): 58 """Create a new copy.""" 59 return Arguments(list(self._args)) 60 61 @staticmethod 62 def build(arg_str): 63 """Build and Arguments instance from an argument string. 64 65 Parameters 66 ---------- 67 arg_str : str 68 String describing the event arguments. 69 """ 70 res = [] 71 for arg in arg_str.split(","): 72 arg = arg.strip() 73 if arg == 'void': 74 continue 75 76 if '*' in arg: 77 arg_type, identifier = arg.rsplit('*', 1) 78 arg_type += '*' 79 identifier = identifier.strip() 80 else: 81 arg_type, identifier = arg.rsplit(None, 1) 82 83 res.append((arg_type, identifier)) 84 return Arguments(res) 85 86 def __iter__(self): 87 """Iterate over the (type, name) pairs.""" 88 return iter(self._args) 89 90 def __len__(self): 91 """Number of arguments.""" 92 return len(self._args) 93 94 def __str__(self): 95 """String suitable for declaring function arguments.""" 96 if len(self._args) == 0: 97 return "void" 98 else: 99 return ", ".join([ " ".join([t, n]) for t,n in self._args ]) 100 101 def __repr__(self): 102 """Evaluable string representation for this object.""" 103 return "Arguments(\"%s\")" % str(self) 104 105 def names(self): 106 """List of argument names.""" 107 return [ name for _, name in self._args ] 108 109 def types(self): 110 """List of argument types.""" 111 return [ type_ for type_, _ in self._args ] 112 113 def transform(self, *trans): 114 """Return a new Arguments instance with transformed types. 115 116 The types in the resulting Arguments instance are transformed according 117 to tracetool.transform.transform_type. 118 """ 119 res = [] 120 for type_, name in self._args: 121 res.append((tracetool.transform.transform_type(type_, *trans), 122 name)) 123 return Arguments(res) 124 125 126class Event(object): 127 """Event description. 128 129 Attributes 130 ---------- 131 name : str 132 The event name. 133 fmt : str 134 The event format string. 135 properties : set(str) 136 Properties of the event. 137 args : Arguments 138 The event arguments. 139 140 """ 141 142 _CRE = re.compile("((?P<props>[\w\s]+)\s+)?" 143 "(?P<name>\w+)" 144 "\((?P<args>[^)]*)\)" 145 "\s*" 146 "(?:(?:(?P<fmt_trans>\".+),)?\s*(?P<fmt>\".+))?" 147 "\s*") 148 149 _VALID_PROPS = set(["disable", "tcg", "tcg-trans", "tcg-exec"]) 150 151 def __init__(self, name, props, fmt, args, orig=None): 152 """ 153 Parameters 154 ---------- 155 name : string 156 Event name. 157 props : list of str 158 Property names. 159 fmt : str, list of str 160 Event printing format (or formats). 161 args : Arguments 162 Event arguments. 163 orig : Event or None 164 Original Event before transformation. 165 166 """ 167 self.name = name 168 self.properties = props 169 self.fmt = fmt 170 self.args = args 171 172 if orig is None: 173 self.original = weakref.ref(self) 174 else: 175 self.original = orig 176 177 unknown_props = set(self.properties) - self._VALID_PROPS 178 if len(unknown_props) > 0: 179 raise ValueError("Unknown properties: %s" 180 % ", ".join(unknown_props)) 181 assert isinstance(self.fmt, str) or len(self.fmt) == 2 182 183 def copy(self): 184 """Create a new copy.""" 185 return Event(self.name, list(self.properties), self.fmt, 186 self.args.copy(), self) 187 188 @staticmethod 189 def build(line_str): 190 """Build an Event instance from a string. 191 192 Parameters 193 ---------- 194 line_str : str 195 Line describing the event. 196 """ 197 m = Event._CRE.match(line_str) 198 assert m is not None 199 groups = m.groupdict('') 200 201 name = groups["name"] 202 props = groups["props"].split() 203 fmt = groups["fmt"] 204 fmt_trans = groups["fmt_trans"] 205 if len(fmt_trans) > 0: 206 fmt = [fmt_trans, fmt] 207 args = Arguments.build(groups["args"]) 208 209 if "tcg-trans" in props: 210 raise ValueError("Invalid property 'tcg-trans'") 211 if "tcg-exec" in props: 212 raise ValueError("Invalid property 'tcg-exec'") 213 if "tcg" not in props and not isinstance(fmt, str): 214 raise ValueError("Only events with 'tcg' property can have two formats") 215 if "tcg" in props and isinstance(fmt, str): 216 raise ValueError("Events with 'tcg' property must have two formats") 217 218 return Event(name, props, fmt, args) 219 220 def __repr__(self): 221 """Evaluable string representation for this object.""" 222 if isinstance(self.fmt, str): 223 fmt = self.fmt 224 else: 225 fmt = "%s, %s" % (self.fmt[0], self.fmt[1]) 226 return "Event('%s %s(%s) %s')" % (" ".join(self.properties), 227 self.name, 228 self.args, 229 fmt) 230 231 _FMT = re.compile("(%[\d\.]*\w+|%.*PRI\S+)") 232 233 def formats(self): 234 """List of argument print formats.""" 235 assert not isinstance(self.fmt, list) 236 return self._FMT.findall(self.fmt) 237 238 QEMU_TRACE = "trace_%(name)s" 239 QEMU_TRACE_TCG = QEMU_TRACE + "_tcg" 240 241 def api(self, fmt=None): 242 if fmt is None: 243 fmt = Event.QEMU_TRACE 244 return fmt % {"name": self.name} 245 246 def transform(self, *trans): 247 """Return a new Event with transformed Arguments.""" 248 return Event(self.name, 249 list(self.properties), 250 self.fmt, 251 self.args.transform(*trans), 252 self) 253 254 255def _read_events(fobj): 256 res = [] 257 for line in fobj: 258 if not line.strip(): 259 continue 260 if line.lstrip().startswith('#'): 261 continue 262 res.append(Event.build(line)) 263 return res 264 265 266class TracetoolError (Exception): 267 """Exception for calls to generate.""" 268 pass 269 270 271def try_import(mod_name, attr_name=None, attr_default=None): 272 """Try to import a module and get an attribute from it. 273 274 Parameters 275 ---------- 276 mod_name : str 277 Module name. 278 attr_name : str, optional 279 Name of an attribute in the module. 280 attr_default : optional 281 Default value if the attribute does not exist in the module. 282 283 Returns 284 ------- 285 A pair indicating whether the module could be imported and the module or 286 object or attribute value. 287 """ 288 try: 289 module = __import__(mod_name, globals(), locals(), ["__package__"]) 290 if attr_name is None: 291 return True, module 292 return True, getattr(module, str(attr_name), attr_default) 293 except ImportError: 294 return False, None 295 296 297def generate(fevents, format, backends, 298 binary=None, probe_prefix=None): 299 """Generate the output for the given (format, backends) pair. 300 301 Parameters 302 ---------- 303 fevents : file 304 Event description file. 305 format : str 306 Output format name. 307 backends : list 308 Output backend names. 309 binary : str or None 310 See tracetool.backend.dtrace.BINARY. 311 probe_prefix : str or None 312 See tracetool.backend.dtrace.PROBEPREFIX. 313 """ 314 # fix strange python error (UnboundLocalError tracetool) 315 import tracetool 316 317 format = str(format) 318 if len(format) is 0: 319 raise TracetoolError("format not set") 320 if not tracetool.format.exists(format): 321 raise TracetoolError("unknown format: %s" % format) 322 323 if len(backends) is 0: 324 raise TracetoolError("no backends specified") 325 for backend in backends: 326 if not tracetool.backend.exists(backend): 327 raise TracetoolError("unknown backend: %s" % backend) 328 backend = tracetool.backend.Wrapper(backends, format) 329 330 import tracetool.backend.dtrace 331 tracetool.backend.dtrace.BINARY = binary 332 tracetool.backend.dtrace.PROBEPREFIX = probe_prefix 333 334 events = _read_events(fevents) 335 336 # transform TCG-enabled events 337 new_events = [] 338 for event in events: 339 if "tcg" not in event.properties: 340 new_events.append(event) 341 else: 342 event_trans = event.copy() 343 event_trans.name += "_trans" 344 event_trans.properties += ["tcg-trans"] 345 event_trans.fmt = event.fmt[0] 346 args_trans = [] 347 for atrans, aorig in zip( 348 event_trans.transform(tracetool.transform.TCG_2_HOST).args, 349 event.args): 350 if atrans == aorig: 351 args_trans.append(atrans) 352 event_trans.args = Arguments(args_trans) 353 event_trans = event_trans.copy() 354 355 event_exec = event.copy() 356 event_exec.name += "_exec" 357 event_exec.properties += ["tcg-exec"] 358 event_exec.fmt = event.fmt[1] 359 event_exec = event_exec.transform(tracetool.transform.TCG_2_HOST) 360 361 new_event = [event_trans, event_exec] 362 event.event_trans, event.event_exec = new_event 363 364 new_events.extend(new_event) 365 events = new_events 366 367 tracetool.format.generate(events, format, backend) 368