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;
 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         s = nsecs / NSECS_PER_SEC;
 236         ns = nsecs - s * NSECS_PER_SEC;
 237
 238         scripting_context->event_data = data;
 239
 240         context = PyCObject_FromVoidPtr(scripting_context, NULL);
 241
 242         PyTuple_SetItem(t, n++, PyString_FromString(handler_name));
 243         PyTuple_SetItem(t, n++,
 244                         PyCObject_FromVoidPtr(scripting_context, NULL));
 245         PyTuple_SetItem(t, n++, PyInt_FromLong(cpu));
 246         PyTuple_SetItem(t, n++, PyInt_FromLong(s));
 247         PyTuple_SetItem(t, n++, PyInt_FromLong(ns));
 248         PyTuple_SetItem(t, n++, PyInt_FromLong(pid));
 249         PyTuple_SetItem(t, n++, PyString_FromString(comm));
 250
 251         for (field = event->format.fields; field; field = field->next) {
 252                 if (field->flags & FIELD_IS_STRING) {
 253                         int offset;
 254                         if (field->flags & FIELD_IS_DYNAMIC) {
 255                                 offset = *(int *)(data + field->offset);
 256                                 offset &= 0xffff;
 257                         } else
 258                                 offset = field->offset;
 259                         obj = PyString_FromString((char *)data + offset);
 260                 } else { /* FIELD_IS_NUMERIC */
 261                         val = read_size(data + field->offset, field->size);
 262                         if (field->flags & FIELD_IS_SIGNED) {
 263                                 if ((long long)val >= LONG_MIN &&
 264                                     (long long)val <= LONG_MAX)
 265                                         obj = PyInt_FromLong(val);
 266                                 else
 267                                         obj = PyLong_FromLongLong(val);
 268                         } else {
 269                                 if (val <= LONG_MAX)
 270                                         obj = PyInt_FromLong(val);
 271                                 else
 272                                         obj = PyLong_FromUnsignedLongLong(val);
 273                         }
 274                 }
 275                 PyTuple_SetItem(t, n++, obj);
 276         }
 277
 278         if (_PyTuple_Resize(&t, n) == -1)
 279                 Py_FatalError("error resizing Python tuple");
 280
 281         handler = PyDict_GetItemString(main_dict, handler_name);
 282         if (handler && PyCallable_Check(handler)) {
 283                 retval = PyObject_CallObject(handler, t);
 284                 if (retval == NULL)
 285                         handler_call_die(handler_name);
 286         } else {
 287                 handler = PyDict_GetItemString(main_dict, "trace_unhandled");
 288                 if (handler && PyCallable_Check(handler)) {
 289                         if (_PyTuple_Resize(&t, N_COMMON_FIELDS) == -1)
 290                                 Py_FatalError("error resizing Python tuple");
 291
 292                         retval = PyObject_CallObject(handler, t);
 293                         if (retval == NULL)
 294                                 handler_call_die("trace_unhandled");
 295                 }
 296         }
 297
 298         Py_DECREF(t);
 299 }
 300
 301 static int run_start_sub(void)
 302 {
 303         PyObject *handler, *retval;
 304         int err = 0;
 305
 306         main_module = PyImport_AddModule("__main__");
 307         if (main_module == NULL)
 308                 return -1;
 309         Py_INCREF(main_module);
 310
 311         main_dict = PyModule_GetDict(main_module);
 312         if (main_dict == NULL) {
 313                 err = -1;
 314                 goto error;
 315         }
 316         Py_INCREF(main_dict);
 317
 318         handler = PyDict_GetItemString(main_dict, "trace_begin");
 319         if (handler == NULL || !PyCallable_Check(handler))
 320                 goto out;
 321
 322         retval = PyObject_CallObject(handler, NULL);
 323         if (retval == NULL)
 324                 handler_call_die("trace_begin");
 325
 326         Py_DECREF(retval);
 327         return err;
 328 error:
 329         Py_XDECREF(main_dict);
 330         Py_XDECREF(main_module);
 331 out:
 332         return err;
 333 }
 334
 335 /*
 336  * Start trace script
 337  */
 338 static int python_start_script(const char *script, int argc, const char **argv)
 339 {
 340         const char **command_line;
 341         char buf[PATH_MAX];
 342         int i, err = 0;
 343         FILE *fp;
 344
 345         command_line = malloc((argc + 1) * sizeof(const char *));
 346         command_line[0] = script;
 347         for (i = 1; i < argc + 1; i++)
 348                 command_line[i] = argv[i - 1];
 349
 350         Py_Initialize();
 351
 352         initperf_trace_context();
 353
 354         PySys_SetArgv(argc + 1, (char **)command_line);
 355
 356         fp = fopen(script, "r");
 357         if (!fp) {
 358                 sprintf(buf, "Can't open python script \"%s\"", script);
 359                 perror(buf);
 360                 err = -1;
 361                 goto error;
 362         }
 363
 364         err = PyRun_SimpleFile(fp, script);
 365         if (err) {
 366                 fprintf(stderr, "Error running python script %s\n", script);
 367                 goto error;
 368         }
 369
 370         err = run_start_sub();
 371         if (err) {
 372                 fprintf(stderr, "Error starting python script %s\n", script);
 373                 goto error;
 374         }
 375
 376         free(command_line);
 377
 378         return err;
 379 error:
 380         Py_Finalize();
 381         free(command_line);
 382
 383         return err;
 384 }
 385
 386 /*
 387  * Stop trace script
 388  */
 389 static int python_stop_script(void)
 390 {
 391         PyObject *handler, *retval;
 392         int err = 0;
 393
 394         handler = PyDict_GetItemString(main_dict, "trace_end");
 395         if (handler == NULL || !PyCallable_Check(handler))
 396                 goto out;
 397
 398         retval = PyObject_CallObject(handler, NULL);
 399         if (retval == NULL)
 400                 handler_call_die("trace_end");
 401         else
 402                 Py_DECREF(retval);
 403 out:
 404         Py_XDECREF(main_dict);
 405         Py_XDECREF(main_module);
 406         Py_Finalize();
 407
 408         return err;
 409 }
 410
 411 static int python_generate_script(const char *outfile)
 412 {
 413         struct event *event = NULL;
 414         struct format_field *f;
 415         char fname[PATH_MAX];
 416         int not_first, count;
 417         FILE *ofp;
 418
 419         sprintf(fname, "%s.py", outfile);
 420         ofp = fopen(fname, "w");
 421         if (ofp == NULL) {
 422                 fprintf(stderr, "couldn't open %s\n", fname);
 423                 return -1;
 424         }
 425         fprintf(ofp, "# perf trace event handlers, "
 426                 "generated by perf trace -g python\n");
 427
 428         fprintf(ofp, "# Licensed under the terms of the GNU GPL"
 429                 " License version 2\n\n");
 430
 431         fprintf(ofp, "# The common_* event handler fields are the most useful "
 432                 "fields common to\n");
 433
 434         fprintf(ofp, "# all events.  They don't necessarily correspond to "
 435                 "the 'common_*' fields\n");
 436
 437         fprintf(ofp, "# in the format files.  Those fields not available as "
 438                 "handler params can\n");
 439
 440         fprintf(ofp, "# be retrieved using Python functions of the form "
 441                 "common_*(context).\n");
 442
 443         fprintf(ofp, "# See the perf-trace-python Documentation for the list "
 444                 "of available functions.\n\n");
 445
 446         fprintf(ofp, "import os\n");
 447         fprintf(ofp, "import sys\n\n");
 448
 449         fprintf(ofp, "sys.path.append(os.environ['PERF_EXEC_PATH'] + \\\n");
 450         fprintf(ofp, "\t'/scripts/python/Perf-Trace-Util/lib/Perf/Trace')\n");
 451         fprintf(ofp, "\nfrom perf_trace_context import *\n");
 452         fprintf(ofp, "from Core import *\n\n\n");
 453
 454         fprintf(ofp, "def trace_begin():\n");
 455         fprintf(ofp, "\tprint \"in trace_begin\"\n\n");
 456
 457         fprintf(ofp, "def trace_end():\n");
 458         fprintf(ofp, "\tprint \"in trace_end\"\n\n");
 459
 460         while ((event = trace_find_next_event(event))) {
 461                 fprintf(ofp, "def %s__%s(", event->system, event->name);
 462                 fprintf(ofp, "event_name, ");
 463                 fprintf(ofp, "context, ");
 464                 fprintf(ofp, "common_cpu,\n");
 465                 fprintf(ofp, "\tcommon_secs, ");
 466                 fprintf(ofp, "common_nsecs, ");
 467                 fprintf(ofp, "common_pid, ");
 468                 fprintf(ofp, "common_comm,\n\t");
 469
 470                 not_first = 0;
 471                 count = 0;
 472
 473                 for (f = event->format.fields; f; f = f->next) {
 474                         if (not_first++)
 475                                 fprintf(ofp, ", ");
 476                         if (++count % 5 == 0)
 477                                 fprintf(ofp, "\n\t");
 478
 479                         fprintf(ofp, "%s", f->name);
 480                 }
 481                 fprintf(ofp, "):\n");
 482
 483                 fprintf(ofp, "\t\tprint_header(event_name, common_cpu, "
 484                         "common_secs, common_nsecs,\n\t\t\t"
 485                         "common_pid, common_comm)\n\n");
 486
 487                 fprintf(ofp, "\t\tprint \"");
 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 && count % 3 == 0) {
 496                                 fprintf(ofp, "\" \\\n\t\t\"");
 497                         }
 498                         count++;
 499
 500                         fprintf(ofp, "%s=", f->name);
 501                         if (f->flags & FIELD_IS_STRING ||
 502                             f->flags & FIELD_IS_FLAG ||
 503                             f->flags & FIELD_IS_SYMBOLIC)
 504                                 fprintf(ofp, "%%s");
 505                         else if (f->flags & FIELD_IS_SIGNED)
 506                                 fprintf(ofp, "%%d");
 507                         else
 508                                 fprintf(ofp, "%%u");
 509                 }
 510
 511                 fprintf(ofp, "\\n\" %% \\\n\t\t(");
 512
 513                 not_first = 0;
 514                 count = 0;
 515
 516                 for (f = event->format.fields; f; f = f->next) {
 517                         if (not_first++)
 518                                 fprintf(ofp, ", ");
 519
 520                         if (++count % 5 == 0)
 521                                 fprintf(ofp, "\n\t\t");
 522
 523                         if (f->flags & FIELD_IS_FLAG) {
 524                                 if ((count - 1) % 5 != 0) {
 525                                         fprintf(ofp, "\n\t\t");
 526                                         count = 4;
 527                                 }
 528                                 fprintf(ofp, "flag_str(\"");
 529                                 fprintf(ofp, "%s__%s\", ", event->system,
 530                                         event->name);
 531                                 fprintf(ofp, "\"%s\", %s)", f->name,
 532                                         f->name);
 533                         } else if (f->flags & FIELD_IS_SYMBOLIC) {
 534                                 if ((count - 1) % 5 != 0) {
 535                                         fprintf(ofp, "\n\t\t");
 536                                         count = 4;
 537                                 }
 538                                 fprintf(ofp, "symbol_str(\"");
 539                                 fprintf(ofp, "%s__%s\", ", event->system,
 540                                         event->name);
 541                                 fprintf(ofp, "\"%s\", %s)", f->name,
 542                                         f->name);
 543                         } else
 544                                 fprintf(ofp, "%s", f->name);
 545                 }
 546
 547                 fprintf(ofp, "),\n\n");
 548         }
 549
 550         fprintf(ofp, "def trace_unhandled(event_name, context, "
 551                 "common_cpu, common_secs, common_nsecs,\n\t\t"
 552                 "common_pid, common_comm):\n");
 553
 554         fprintf(ofp, "\t\tprint_header(event_name, common_cpu, "
 555                 "common_secs, common_nsecs,\n\t\tcommon_pid, "
 556                 "common_comm)\n\n");
 557
 558         fprintf(ofp, "def print_header("
 559                 "event_name, cpu, secs, nsecs, pid, comm):\n"
 560                 "\tprint \"%%-20s %%5u %%05u.%%09u %%8u %%-20s \" %% \\\n\t"
 561                 "(event_name, cpu, secs, nsecs, pid, comm),\n");
 562
 563         fclose(ofp);
 564
 565         fprintf(stderr, "generated Python script: %s\n", fname);
 566
 567         return 0;
 568 }
 569
 570 struct scripting_ops python_scripting_ops = {
 571         .name = "Python",
 572         .start_script = python_start_script,
 573         .stop_script = python_stop_script,
 574         .process_event = python_process_event,
 575         .generate_script = python_generate_script,
 576 };