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 _CRE = re.compile("((?P<props>.*)\s+)?" 142 "(?P<name>[^(\s]+)" 143 "\((?P<args>[^)]*)\)" 144 "\s*" 145 "(?:(?:(?P<fmt_trans>\".+),)?\s*(?P<fmt>\".+))?" 146 "\s*") 147 148 _VALID_PROPS = set(["disable", "tcg", "tcg-trans", "tcg-exec"]) 149 150 def __init__(self, name, props, fmt, args, orig=None): 151 """ 152 Parameters 153 ---------- 154 name : string 155 Event name. 156 props : list of str 157 Property names. 158 fmt : str, list of str 159 Event printing format (or formats). 160 args : Arguments 161 Event arguments. 162 orig : Event or None 163 Original Event before transformation. 164 """ 165 self.name = name 166 self.properties = props 167 self.fmt = fmt 168 self.args = args 169 170 if orig is None: 171 self.original = weakref.ref(self) 172 else: 173 self.original = orig 174 175 unknown_props = set(self.properties) - self._VALID_PROPS 176 if len(unknown_props) > 0: 177 raise ValueError("Unknown properties: %s" 178 % ", ".join(unknown_props)) 179 assert isinstance(self.fmt, str) or len(self.fmt) == 2 180 181 def copy(self): 182 """Create a new copy.""" 183 return Event(self.name, list(self.properties), self.fmt, 184 self.args.copy(), self) 185 186 @staticmethod 187 def build(line_str): 188 """Build an Event instance from a string. 189 190 Parameters 191 ---------- 192 line_str : str 193 Line describing the event. 194 """ 195 m = Event._CRE.match(line_str) 196 assert m is not None 197 groups = m.groupdict('') 198 199 name = groups["name"] 200 props = groups["props"].split() 201 fmt = groups["fmt"] 202 fmt_trans = groups["fmt_trans"] 203 if len(fmt_trans) > 0: 204 fmt = [fmt_trans, fmt] 205 args = Arguments.build(groups["args"]) 206 207 if "tcg-trans" in props: 208 raise ValueError("Invalid property 'tcg-trans'") 209 if "tcg-exec" in props: 210 raise ValueError("Invalid property 'tcg-exec'") 211 if "tcg" not in props and not isinstance(fmt, str): 212 raise ValueError("Only events with 'tcg' property can have two formats") 213 if "tcg" in props and isinstance(fmt, str): 214 raise ValueError("Events with 'tcg' property must have two formats") 215 216 return Event(name, props, fmt, args) 217 218 def __repr__(self): 219 """Evaluable string representation for this object.""" 220 if isinstance(self.fmt, str): 221 fmt = self.fmt 222 else: 223 fmt = "%s, %s" % (self.fmt[0], self.fmt[1]) 224 return "Event('%s %s(%s) %s')" % (" ".join(self.properties), 225 self.name, 226 self.args, 227 fmt) 228 229 QEMU_TRACE = "trace_%(name)s" 230 QEMU_TRACE_TCG = QEMU_TRACE + "_tcg" 231 232 def api(self, fmt=None): 233 if fmt is None: 234 fmt = Event.QEMU_TRACE 235 return fmt % {"name": self.name} 236 237 def transform(self, *trans): 238 """Return a new Event with transformed Arguments.""" 239 return Event(self.name, 240 list(self.properties), 241 self.fmt, 242 self.args.transform(*trans), 243 self) 244 245 246def _read_events(fobj): 247 res = [] 248 for line in fobj: 249 if not line.strip(): 250 continue 251 if line.lstrip().startswith('#'): 252 continue 253 res.append(Event.build(line)) 254 return res 255 256 257class TracetoolError (Exception): 258 """Exception for calls to generate.""" 259 pass 260 261 262def try_import(mod_name, attr_name=None, attr_default=None): 263 """Try to import a module and get an attribute from it. 264 265 Parameters 266 ---------- 267 mod_name : str 268 Module name. 269 attr_name : str, optional 270 Name of an attribute in the module. 271 attr_default : optional 272 Default value if the attribute does not exist in the module. 273 274 Returns 275 ------- 276 A pair indicating whether the module could be imported and the module or 277 object or attribute value. 278 """ 279 try: 280 module = __import__(mod_name, globals(), locals(), ["__package__"]) 281 if attr_name is None: 282 return True, module 283 return True, getattr(module, str(attr_name), attr_default) 284 except ImportError: 285 return False, None 286 287 288def generate(fevents, format, backends, 289 binary=None, probe_prefix=None): 290 """Generate the output for the given (format, backends) pair. 291 292 Parameters 293 ---------- 294 fevents : file 295 Event description file. 296 format : str 297 Output format name. 298 backends : list 299 Output backend names. 300 binary : str or None 301 See tracetool.backend.dtrace.BINARY. 302 probe_prefix : str or None 303 See tracetool.backend.dtrace.PROBEPREFIX. 304 """ 305 # fix strange python error (UnboundLocalError tracetool) 306 import tracetool 307 308 format = str(format) 309 if len(format) is 0: 310 raise TracetoolError("format not set") 311 if not tracetool.format.exists(format): 312 raise TracetoolError("unknown format: %s" % format) 313 314 if len(backends) is 0: 315 raise TracetoolError("no backends specified") 316 for backend in backends: 317 if not tracetool.backend.exists(backend): 318 raise TracetoolError("unknown backend: %s" % backend) 319 backend = tracetool.backend.Wrapper(backends, format) 320 321 import tracetool.backend.dtrace 322 tracetool.backend.dtrace.BINARY = binary 323 tracetool.backend.dtrace.PROBEPREFIX = probe_prefix 324 325 events = _read_events(fevents) 326 327 # transform TCG-enabled events 328 new_events = [] 329 for event in events: 330 if "tcg" not in event.properties: 331 new_events.append(event) 332 else: 333 event_trans = event.copy() 334 event_trans.name += "_trans" 335 event_trans.properties += ["tcg-trans"] 336 event_trans.fmt = event.fmt[0] 337 args_trans = [] 338 for atrans, aorig in zip( 339 event_trans.transform(tracetool.transform.TCG_2_HOST).args, 340 event.args): 341 if atrans == aorig: 342 args_trans.append(atrans) 343 event_trans.args = Arguments(args_trans) 344 event_trans = event_trans.copy() 345 346 event_exec = event.copy() 347 event_exec.name += "_exec" 348 event_exec.properties += ["tcg-exec"] 349 event_exec.fmt = event.fmt[1] 350 event_exec = event_exec.transform(tracetool.transform.TCG_2_HOST) 351 352 new_event = [event_trans, event_exec] 353 event.event_trans, event.event_exec = new_event 354 355 new_events.extend(new_event) 356 events = new_events 357 358 tracetool.format.generate(events, format, backend) 359