tools/perf/util/scripting-engines/trace-event-python.c

   1 /*
   2  * trace-event-python.  Feed trace events to an embedded Python interpreter.
   3  *
   4  * Copyright (C) 2010 Tom Zanussi <tzanussi@gmail.com>
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 #include <Python.h>
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <ctype.h>
  28 #include <errno.h>
  29
  30 #include "../../perf.h"
  31 #include "../util.h"
  32 #include "../trace-event.h"
  33
  34 PyMODINIT_FUNC initperf_trace_context(void);
  35
  36 #define FTRACE_MAX_EVENT                                \
  37         ((1 << (sizeof(unsigned short) * 8)) - 1)
  38
  39 struct event *events[FTRACE_MAX_EVENT];
  40
  41 #define MAX_FIELDS      64
  42 #define N_COMMON_FIELDS 7
  43
  44 extern struct scripting_context *scripting_context;
  45
  46 static char *cur_field_name;
  47 static int zero_flag_atom;
  48
  49 static PyObject *main_module, *main_dict;
  50
  51 static void handler_call_die(const char *handler_name)
  52 {
  53         PyErr_Print();
  54         Py_FatalError("problem in Python trace event handler");
  55 }
  56
  57 static void define_value(enum print_arg_type field_type,
  58                          const char *ev_name,
  59                          const char *field_name,
  60                          const char *field_value,
  61                          const char *field_str)
  62 {
  63         const char *handler_name = "define_flag_value";
  64         PyObject *handler, *t, *retval;
  65         unsigned long long value;
  66         unsigned n = 0;
  67
  68         if (field_type == PRINT_SYMBOL)
  69                 handler_name = "define_symbolic_value";
  70
  71         t = PyTuple_New(4);
  72         if (!t)
  73                 Py_FatalError("couldn't create Python tuple");
  74
  75         value = eval_flag(field_value);
  76
  77         PyTuple_SetItem(t, n++, PyString_FromString(ev_name));
  78         PyTuple_SetItem(t, n++, PyString_FromString(field_name));
  79         PyTuple_SetItem(t, n++, PyInt_FromLong(value));
  80         PyTuple_SetItem(t, n++, PyString_FromString(field_str));
  81
  82         handler = PyDict_GetItemString(main_dict, handler_name);
  83         if (handler && PyCallable_Check(handler)) {
  84                 retval = PyObject_CallObject(handler, t);
  85                 if (retval == NULL)
  86                         handler_call_die(handler_name);
  87         }
  88
  89         Py_DECREF(t);
  90 }
  91
  92 static void define_values(enum print_arg_type field_type,
  93                           struct print_flag_sym *field,
  94                           const char *ev_name,
  95                           const char *field_name)
  96 {
  97         define_value(field_type, ev_name, field_name, field->value,
  98                      field->str);
  99
 100         if (field->next)
 101                 define_values(field_type, field->next, ev_name, field_name);
 102 }
 103
 104 static void define_field(enum print_arg_type field_type,
 105                          const char *ev_name,
 106                          const char *field_name,
 107                          const char *delim)
 108 {
 109         const char *handler_name = "define_flag_field";
 110         PyObject *handler, *t, *retval;
 111         unsigned n = 0;
 112
 113         if (field_type == PRINT_SYMBOL)
 114                 handler_name = "define_symbolic_field";
 115
 116         if (field_type == PRINT_FLAGS)
 117                 t = PyTuple_New(3);
 118         else
 119                 t = PyTuple_New(2);
 120         if (!t)
 121                 Py_FatalError("couldn't create Python tuple");
 122
 123         PyTuple_SetItem(t, n++, PyString_FromString(ev_name));
 124         PyTuple_SetItem(t, n++, PyString_FromString(field_name));
 125         if (field_type == PRINT_FLAGS)
 126                 PyTuple_SetItem(t, n++, PyString_FromString(delim));
 127
 128         handler = PyDict_GetItemString(main_dict, handler_name);
 129         if (handler && PyCallable_Check(handler)) {
 130                 retval = PyObject_CallObject(handler, t);
 131                 if (retval == NULL)
 132                         handler_call_die(handler_name);
 133         }
 134
 135         Py_DECREF(t);
 136 }
 137
 138 static void define_event_symbols(struct event *event,
 139                                  const char *ev_name,
 140                                  struct print_arg *args)
 141 {
 142         switch (args->type) {
 143         case PRINT_NULL:
 144                 break;
 145         case PRINT_ATOM:
 146                 define_value(PRINT_FLAGS, ev_name, cur_field_name, "0",
 147                              args->atom.atom);
 148                 zero_flag_atom = 0;
 149                 break;
 150         case PRINT_FIELD:
 151                 if (cur_field_name)
 152                         free(cur_field_name);
 153                 cur_field_name = strdup(args->field.name);
 154                 break;
 155         case PRINT_FLAGS:
 156                 define_event_symbols(event, ev_name, args->flags.field);
 157                 define_field(PRINT_FLAGS, ev_name, cur_field_name,
 158                              args->flags.delim);
 159                 define_values(PRINT_FLAGS, args->flags.flags, ev_name,
 160                               cur_field_name);
 161                 break;
 162         case PRINT_SYMBOL:
 163                 define_event_symbols(event, ev_name, args->symbol.field);
 164                 define_field(PRINT_SYMBOL, ev_name, cur_field_name, NULL);
 165                 define_values(PRINT_SYMBOL, args->symbol.symbols, ev_name,
 166                               cur_field_name);
 167                 break;
 168         case PRINT_STRING:
 169                 break;
 170         case PRINT_TYPE:
 171                 define_event_symbols(event, ev_name, args->typecast.item);
 172                 break;
 173         case PRINT_OP:
 174                 if (strcmp(args->op.op, ":") == 0)
 175                         zero_flag_atom = 1;
 176                 define_event_symbols(event, ev_name, args->op.left);
 177                 define_event_symbols(event, ev_name, args->op.right);
 178                 break;
 179         default:
 180                 /* we should warn... */
 181                 return;
 182         }
 183
 184         if (args->next)
 185                 define_event_symbols(event, ev_name, args->next);
 186 }
 187
 188 static inline struct event *find_cache_event(int type)
 189 {
 190         static char ev_name[256];
 191         struct event *event;
 192
 193         if (events[type])
 194                 return events[type];
 195
 196         events[type] = event = trace_find_event(type);
 197         if (!event)
 198                 return NULL;
 199
 200         sprintf(ev_name, "%s__%s", event->system, event->name);
 201
 202         define_event_symbols(event, ev_name, event->print_fmt.args);
 203
 204         return event;
 205 }
 206
 207 static void python_process_event(int cpu, void *data,
 208                                  int size __unused,
 209                                  unsigned long long nsecs, char *comm)
 210 {
 211         PyObject *handler, *retval, *context, *t, *obj, *dict = NULL;
 212         static char handler_name[256];
 213         struct format_field *field;
 214         unsigned long long val;
 215         unsigned long s, ns;
 216         struct event *event;
 217         unsigned n = 0;
 218         int type;
 219         int pid;
 220
 221         t = PyTuple_New(MAX_FIELDS);
 222         if (!t)
 223                 Py_FatalError("couldn't create Python tuple");
 224
 225         type = trace_parse_common_type(data);
 226
 227         event = find_cache_event(type);
 228         if (!event)
 229                 die("ug! no event found for type %d", type);
 230
 231         pid = trace_parse_common_pid(data);
 232
 233         sprintf(handler_name, "%s__%s", event->system, event->name);
 234
 235         handler = PyDict_GetItemString(main_dict, handler_name);
 236         if (handler && !PyCallable_Check(handler))
 237                 handler = NULL;
 238         if (!handler) {
 239                 dict = PyDict_New();
 240                 if (!dict)
 241                         Py_FatalError("couldn't create Python dict");
 242         }
 243         s = nsecs / NSECS_PER_SEC;
 244         ns = nsecs - s * NSECS_PER_SEC;
 245
 246         scripting_context->event_data = data;
 247
 248         context = PyCObject_FromVoidPtr(scripting_context, NULL);
 249
 250         PyTuple_SetItem(t, n++, PyString_FromString(handler_name));
 251         PyTuple_SetItem(t, n++, context);
 252
 253         if (handler) {
 254                 PyTuple_SetItem(t, n++, PyInt_FromLong(cpu));
 255                 PyTuple_SetItem(t, n++, PyInt_FromLong(s));
 256                 PyTuple_SetItem(t, n++, PyInt_FromLong(ns));
 257                 PyTuple_SetItem(t, n++, PyInt_FromLong(pid));
 258                 PyTuple_SetItem(t, n++, PyString_FromString(comm));
 259         } else {
 260                 PyDict_SetItemString(dict, "common_cpu", PyInt_FromLong(cpu));
 261                 PyDict_SetItemString(dict, "common_s", PyInt_FromLong(s));
 262                 PyDict_SetItemString(dict, "common_ns", PyInt_FromLong(ns));
 263                 PyDict_SetItemString(dict, "common_pid", PyInt_FromLong(pid));
 264                 PyDict_SetItemString(dict, "common_comm", PyString_FromString(comm));
 265         }
 266         for (field = event->format.fields; field; field = field->next) {
 267                 if (field->flags & FIELD_IS_STRING) {
 268                         int offset;
 269                         if (field->flags & FIELD_IS_DYNAMIC) {
 270                                 offset = *(int *)(data + field->offset);
 271                                 offset &= 0xffff;
 272                         } else
 273                                 offset = field->offset;
 274                         obj = PyString_FromString((char *)data + offset);
 275                 } else { /* FIELD_IS_NUMERIC */
 276                         val = read_size(data + field->offset, field->size);
 277                         if (field->flags & FIELD_IS_SIGNED) {
 278                                 if ((long long)val >= LONG_MIN &&
 279                                     (long long)val <= LONG_MAX)
 280                                         obj = PyInt_FromLong(val);
 281                                 else
 282                                         obj = PyLong_FromLongLong(val);
 283                         } else {
 284                                 if (val <= LONG_MAX)
 285                                         obj = PyInt_FromLong(val);
 286                                 else
 287                                         obj = PyLong_FromUnsignedLongLong(val);
 288                         }
 289                 }
 290                 if (handler)
 291                         PyTuple_SetItem(t, n++, obj);
 292                 else
 293                         PyDict_SetItemString(dict, field->name, obj);
 294
 295         }
 296         if (!handler)
 297                 PyTuple_SetItem(t, n++, dict);
 298
 299         if (_PyTuple_Resize(&t, n) == -1)
 300                 Py_FatalError("error resizing Python tuple");
 301
 302         if (handler) {
 303                 retval = PyObject_CallObject(handler, t);
 304                 if (retval == NULL)
 305                         handler_call_die(handler_name);
 306         } else {
 307                 handler = PyDict_GetItemString(main_dict, "trace_unhandled");
 308                 if (handler && PyCallable_Check(handler)) {
 309
 310                         retval = PyObject_CallObject(handler, t);
 311                         if (retval == NULL)
 312                                 handler_call_die("trace_unhandled");
 313                 }
 314                 Py_DECREF(dict);
 315         }
 316
 317         Py_DECREF(t);
 318 }
 319
 320 static int run_start_sub(void)
 321 {
 322         PyObject *handler, *retval;
 323         int err = 0;
 324
 325         main_module = PyImport_AddModule("__main__");
 326         if (main_module == NULL)
 327                 return -1;
 328         Py_INCREF(main_module);
 329
 330         main_dict = PyModule_GetDict(main_module);
 331         if (main_dict == NULL) {
 332                 err = -1;
 333                 goto error;
 334         }
 335         Py_INCREF(main_dict);
 336
 337         handler = PyDict_GetItemString(main_dict, "trace_begin");
 338         if (handler == NULL || !PyCallable_Check(handler))
 339                 goto out;
 340
 341         retval = PyObject_CallObject(handler, NULL);
 342         if (retval == NULL)
 343                 handler_call_die("trace_begin");
 344
 345         Py_DECREF(retval);
 346         return err;
 347 error:
 348         Py_XDECREF(main_dict);
 349         Py_XDECREF(main_module);
 350 out:
 351         return err;
 352 }
 353
 354 /*
 355  * Start trace script
 356  */
 357 static int python_start_script(const char *script, int argc, const char **argv)
 358 {
 359         const char **command_line;
 360         char buf[PATH_MAX];
 361         int i, err = 0;
 362         FILE *fp;
 363
 364         command_line = malloc((argc + 1) * sizeof(const char *));
 365         command_line[0] = script;
 366         for (i = 1; i < argc + 1; i++)
 367                 command_line[i] = argv[i - 1];
 368
 369         Py_Initialize();
 370
 371         initperf_trace_context();
 372
 373         PySys_SetArgv(argc + 1, (char **)command_line);
 374
 375         fp = fopen(script, "r");
 376         if (!fp) {
 377                 sprintf(buf, "Can't open python script \"%s\"", script);
 378                 perror(buf);
 379                 err = -1;
 380                 goto error;
 381         }
 382
 383         err = PyRun_SimpleFile(fp, script);
 384         if (err) {
 385                 fprintf(stderr, "Error running python script %s\n", script);
 386                 goto error;
 387         }
 388
 389         err = run_start_sub();
 390         if (err) {
 391                 fprintf(stderr, "Error starting python script %s\n", script);
 392                 goto error;
 393         }
 394
 395         free(command_line);
 396
 397         return err;
 398 error:
 399         Py_Finalize();
 400         free(command_line);
 401
 402         return err;
 403 }
 404
 405 /*
 406  * Stop trace script
 407  */
 408 static int python_stop_script(void)
 409 {
 410         PyObject *handler, *retval;
 411         int err = 0;
 412
 413         handler = PyDict_GetItemString(main_dict, "trace_end");
 414         if (handler == NULL || !PyCallable_Check(handler))
 415                 goto out;
 416
 417         retval = PyObject_CallObject(handler, NULL);
 418         if (retval == NULL)
 419                 handler_call_die("trace_end");
 420         else
 421                 Py_DECREF(retval);
 422 out:
 423         Py_XDECREF(main_dict);
 424         Py_XDECREF(main_module);
 425         Py_Finalize();
 426
 427         return err;
 428 }
 429
 430 static int python_generate_script(const char *outfile)
 431 {
 432         struct event *event = NULL;
 433         struct format_field *f;
 434         char fname[PATH_MAX];
 435         int not_first, count;
 436         FILE *ofp;
 437
 438         sprintf(fname, "%s.py", outfile);
 439         ofp = fopen(fname, "w");
 440         if (ofp == NULL) {
 441                 fprintf(stderr, "couldn't open %s\n", fname);
 442                 return -1;
 443         }
 444         fprintf(ofp, "# perf script event handlers, "
 445                 "generated by perf script -g python\n");
 446
 447         fprintf(ofp, "# Licensed under the terms of the GNU GPL"
 448                 " License version 2\n\n");
 449
 450         fprintf(ofp, "# The common_* event handler fields are the most useful "
 451                 "fields common to\n");
 452
 453         fprintf(ofp, "# all events.  They don't necessarily correspond to "
 454                 "the 'common_*' fields\n");
 455
 456         fprintf(ofp, "# in the format files.  Those fields not available as "
 457                 "handler params can\n");
 458
 459         fprintf(ofp, "# be retrieved using Python functions of the form "
 460                 "common_*(context).\n");
 461
 462         fprintf(ofp, "# See the perf-trace-python Documentation for the list "
 463                 "of available functions.\n\n");
 464
 465         fprintf(ofp, "import os\n");
 466         fprintf(ofp, "import sys\n\n");
 467
 468         fprintf(ofp, "sys.path.append(os.environ['PERF_EXEC_PATH'] + \\\n");
 469         fprintf(ofp, "\t'/scripts/python/Perf-Trace-Util/lib/Perf/Trace')\n");
 470         fprintf(ofp, "\nfrom perf_trace_context import *\n");
 471         fprintf(ofp, "from Core import *\n\n\n");
 472
 473         fprintf(ofp, "def trace_begin():\n");
 474         fprintf(ofp, "\tprint \"in trace_begin\"\n\n");
 475
 476         fprintf(ofp, "def trace_end():\n");
 477         fprintf(ofp, "\tprint \"in trace_end\"\n\n");
 478
 479         while ((event = trace_find_next_event(event))) {
 480                 fprintf(ofp, "def %s__%s(", event->system, event->name);
 481                 fprintf(ofp, "event_name, ");
 482                 fprintf(ofp, "context, ");
 483                 fprintf(ofp, "common_cpu,\n");
 484                 fprintf(ofp, "\tcommon_secs, ");
 485                 fprintf(ofp, "common_nsecs, ");
 486                 fprintf(ofp, "common_pid, ");
 487                 fprintf(ofp, "common_comm,\n\t");
 488
 489                 not_first = 0;
 490                 count = 0;
 491
 492                 for (f = event->format.fields; f; f = f->next) {
 493                         if (not_first++)
 494                                 fprintf(ofp, ", ");
 495                         if (++count % 5 == 0)
 496                                 fprintf(ofp, "\n\t");
 497
 498                         fprintf(ofp, "%s", f->name);
 499                 }
 500                 fprintf(ofp, "):\n");
 501
 502                 fprintf(ofp, "\t\tprint_header(event_name, common_cpu, "
 503                         "common_secs, common_nsecs,\n\t\t\t"
 504                         "common_pid, common_comm)\n\n");
 505
 506                 fprintf(ofp, "\t\tprint \"");
 507
 508                 not_first = 0;
 509                 count = 0;
 510
 511                 for (f = event->format.fields; f; f = f->next) {
 512                         if (not_first++)
 513                                 fprintf(ofp, ", ");
 514                         if (count && count % 3 == 0) {
 515                                 fprintf(ofp, "\" \\\n\t\t\"");
 516                         }
 517                         count++;
 518
 519                         fprintf(ofp, "%s=", f->name);
 520                         if (f->flags & FIELD_IS_STRING ||
 521                             f->flags & FIELD_IS_FLAG ||
 522                             f->flags & FIELD_IS_SYMBOLIC)
 523                                 fprintf(ofp, "%%s");
 524                         else if (f->flags & FIELD_IS_SIGNED)
 525                                 fprintf(ofp, "%%d");
 526                         else
 527                                 fprintf(ofp, "%%u");
 528                 }
 529
 530                 fprintf(ofp, "\\n\" %% \\\n\t\t(");
 531
 532                 not_first = 0;
 533                 count = 0;
 534
 535                 for (f = event->format.fields; f; f = f->next) {
 536                         if (not_first++)
 537                                 fprintf(ofp, ", ");
 538
 539                         if (++count % 5 == 0)
 540                                 fprintf(ofp, "\n\t\t");
 541
 542                         if (f->flags & FIELD_IS_FLAG) {
 543                                 if ((count - 1) % 5 != 0) {
 544                                         fprintf(ofp, "\n\t\t");
 545                                         count = 4;
 546                                 }
 547                                 fprintf(ofp, "flag_str(\"");
 548                                 fprintf(ofp, "%s__%s\", ", event->system,
 549                                         event->name);
 550                                 fprintf(ofp, "\"%s\", %s)", f->name,
 551                                         f->name);
 552                         } else if (f->flags & FIELD_IS_SYMBOLIC) {
 553                                 if ((count - 1) % 5 != 0) {
 554                                         fprintf(ofp, "\n\t\t");
 555                                         count = 4;
 556                                 }
 557                                 fprintf(ofp, "symbol_str(\"");
 558                                 fprintf(ofp, "%s__%s\", ", event->system,
 559                                         event->name);
 560                                 fprintf(ofp, "\"%s\", %s)", f->name,
 561                                         f->name);
 562                         } else
 563                                 fprintf(ofp, "%s", f->name);
 564                 }
 565
 566                 fprintf(ofp, "),\n\n");
 567         }
 568
 569         fprintf(ofp, "def trace_unhandled(event_name, context, "
 570                 "event_fields_dict):\n");
 571
 572         fprintf(ofp, "\t\tprint ' '.join(['%%s=%%s'%%(k,str(v))"
 573                 "for k,v in sorted(event_fields_dict.items())])\n\n");
 574
 575         fprintf(ofp, "def print_header("
 576                 "event_name, cpu, secs, nsecs, pid, comm):\n"
 577                 "\tprint \"%%-20s %%5u %%05u.%%09u %%8u %%-20s \" %% \\\n\t"
 578                 "(event_name, cpu, secs, nsecs, pid, comm),\n");
 579
 580         fclose(ofp);
 581
 582         fprintf(stderr, "generated Python script: %s\n", fname);
 583
 584         return 0;
 585 }
 586
 587 struct scripting_ops python_scripting_ops = {
 588         .name = "Python",
 589         .start_script = python_start_script,
 590         .stop_script = python_stop_script,
 591         .process_event = python_process_event,
 592         .generate_script = python_generate_script,
 593 };