linux/tools/perf/util/scripting-engines/trace-event-python.c
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   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
  34PyMODINIT_FUNC initperf_trace_context(void);
  35
  36#define FTRACE_MAX_EVENT                                \
  37        ((1 << (sizeof(unsigned short) * 8)) - 1)
  38
  39struct event *events[FTRACE_MAX_EVENT];
  40
  41#define MAX_FIELDS      64
  42#define N_COMMON_FIELDS 7
  43
  44extern struct scripting_context *scripting_context;
  45
  46static char *cur_field_name;
  47static int zero_flag_atom;
  48
  49static PyObject *main_module, *main_dict;
  50
  51static void handler_call_die(const char *handler_name)
  52{
  53        PyErr_Print();
  54        Py_FatalError("problem in Python trace event handler");
  55}
  56
  57static 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
  92static 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
 104static 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
 138static 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
 188static 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
 207static void python_process_event(union perf_event *pevent __unused,
 208                                 struct perf_sample *sample,
 209                                 struct perf_evsel *evsel __unused,
 210                                 struct perf_session *session __unused,
 211                                 struct thread *thread)
 212{
 213        PyObject *handler, *retval, *context, *t, *obj, *dict = NULL;
 214        static char handler_name[256];
 215        struct format_field *field;
 216        unsigned long long val;
 217        unsigned long s, ns;
 218        struct event *event;
 219        unsigned n = 0;
 220        int type;
 221        int pid;
 222        int cpu = sample->cpu;
 223        void *data = sample->raw_data;
 224        unsigned long long nsecs = sample->time;
 225        char *comm = thread->comm;
 226
 227        t = PyTuple_New(MAX_FIELDS);
 228        if (!t)
 229                Py_FatalError("couldn't create Python tuple");
 230
 231        type = trace_parse_common_type(data);
 232
 233        event = find_cache_event(type);
 234        if (!event)
 235                die("ug! no event found for type %d", type);
 236
 237        pid = trace_parse_common_pid(data);
 238
 239        sprintf(handler_name, "%s__%s", event->system, event->name);
 240
 241        handler = PyDict_GetItemString(main_dict, handler_name);
 242        if (handler && !PyCallable_Check(handler))
 243                handler = NULL;
 244        if (!handler) {
 245                dict = PyDict_New();
 246                if (!dict)
 247                        Py_FatalError("couldn't create Python dict");
 248        }
 249        s = nsecs / NSECS_PER_SEC;
 250        ns = nsecs - s * NSECS_PER_SEC;
 251
 252        scripting_context->event_data = data;
 253
 254        context = PyCObject_FromVoidPtr(scripting_context, NULL);
 255
 256        PyTuple_SetItem(t, n++, PyString_FromString(handler_name));
 257        PyTuple_SetItem(t, n++, context);
 258
 259        if (handler) {
 260                PyTuple_SetItem(t, n++, PyInt_FromLong(cpu));
 261                PyTuple_SetItem(t, n++, PyInt_FromLong(s));
 262                PyTuple_SetItem(t, n++, PyInt_FromLong(ns));
 263                PyTuple_SetItem(t, n++, PyInt_FromLong(pid));
 264                PyTuple_SetItem(t, n++, PyString_FromString(comm));
 265        } else {
 266                PyDict_SetItemString(dict, "common_cpu", PyInt_FromLong(cpu));
 267                PyDict_SetItemString(dict, "common_s", PyInt_FromLong(s));
 268                PyDict_SetItemString(dict, "common_ns", PyInt_FromLong(ns));
 269                PyDict_SetItemString(dict, "common_pid", PyInt_FromLong(pid));
 270                PyDict_SetItemString(dict, "common_comm", PyString_FromString(comm));
 271        }
 272        for (field = event->format.fields; field; field = field->next) {
 273                if (field->flags & FIELD_IS_STRING) {
 274                        int offset;
 275                        if (field->flags & FIELD_IS_DYNAMIC) {
 276                                offset = *(int *)(data + field->offset);
 277                                offset &= 0xffff;
 278                        } else
 279                                offset = field->offset;
 280                        obj = PyString_FromString((char *)data + offset);
 281                } else { /* FIELD_IS_NUMERIC */
 282                        val = read_size(data + field->offset, field->size);
 283                        if (field->flags & FIELD_IS_SIGNED) {
 284                                if ((long long)val >= LONG_MIN &&
 285                                    (long long)val <= LONG_MAX)
 286                                        obj = PyInt_FromLong(val);
 287                                else
 288                                        obj = PyLong_FromLongLong(val);
 289                        } else {
 290                                if (val <= LONG_MAX)
 291                                        obj = PyInt_FromLong(val);
 292                                else
 293                                        obj = PyLong_FromUnsignedLongLong(val);
 294                        }
 295                }
 296                if (handler)
 297                        PyTuple_SetItem(t, n++, obj);
 298                else
 299                        PyDict_SetItemString(dict, field->name, obj);
 300
 301        }
 302        if (!handler)
 303                PyTuple_SetItem(t, n++, dict);
 304
 305        if (_PyTuple_Resize(&t, n) == -1)
 306                Py_FatalError("error resizing Python tuple");
 307
 308        if (handler) {
 309                retval = PyObject_CallObject(handler, t);
 310                if (retval == NULL)
 311                        handler_call_die(handler_name);
 312        } else {
 313                handler = PyDict_GetItemString(main_dict, "trace_unhandled");
 314                if (handler && PyCallable_Check(handler)) {
 315
 316                        retval = PyObject_CallObject(handler, t);
 317                        if (retval == NULL)
 318                                handler_call_die("trace_unhandled");
 319                }
 320                Py_DECREF(dict);
 321        }
 322
 323        Py_DECREF(t);
 324}
 325
 326static int run_start_sub(void)
 327{
 328        PyObject *handler, *retval;
 329        int err = 0;
 330
 331        main_module = PyImport_AddModule("__main__");
 332        if (main_module == NULL)
 333                return -1;
 334        Py_INCREF(main_module);
 335
 336        main_dict = PyModule_GetDict(main_module);
 337        if (main_dict == NULL) {
 338                err = -1;
 339                goto error;
 340        }
 341        Py_INCREF(main_dict);
 342
 343        handler = PyDict_GetItemString(main_dict, "trace_begin");
 344        if (handler == NULL || !PyCallable_Check(handler))
 345                goto out;
 346
 347        retval = PyObject_CallObject(handler, NULL);
 348        if (retval == NULL)
 349                handler_call_die("trace_begin");
 350
 351        Py_DECREF(retval);
 352        return err;
 353error:
 354        Py_XDECREF(main_dict);
 355        Py_XDECREF(main_module);
 356out:
 357        return err;
 358}
 359
 360/*
 361 * Start trace script
 362 */
 363static int python_start_script(const char *script, int argc, const char **argv)
 364{
 365        const char **command_line;
 366        char buf[PATH_MAX];
 367        int i, err = 0;
 368        FILE *fp;
 369
 370        command_line = malloc((argc + 1) * sizeof(const char *));
 371        command_line[0] = script;
 372        for (i = 1; i < argc + 1; i++)
 373                command_line[i] = argv[i - 1];
 374
 375        Py_Initialize();
 376
 377        initperf_trace_context();
 378
 379        PySys_SetArgv(argc + 1, (char **)command_line);
 380
 381        fp = fopen(script, "r");
 382        if (!fp) {
 383                sprintf(buf, "Can't open python script \"%s\"", script);
 384                perror(buf);
 385                err = -1;
 386                goto error;
 387        }
 388
 389        err = PyRun_SimpleFile(fp, script);
 390        if (err) {
 391                fprintf(stderr, "Error running python script %s\n", script);
 392                goto error;
 393        }
 394
 395        err = run_start_sub();
 396        if (err) {
 397                fprintf(stderr, "Error starting python script %s\n", script);
 398                goto error;
 399        }
 400
 401        free(command_line);
 402
 403        return err;
 404error:
 405        Py_Finalize();
 406        free(command_line);
 407
 408        return err;
 409}
 410
 411/*
 412 * Stop trace script
 413 */
 414static int python_stop_script(void)
 415{
 416        PyObject *handler, *retval;
 417        int err = 0;
 418
 419        handler = PyDict_GetItemString(main_dict, "trace_end");
 420        if (handler == NULL || !PyCallable_Check(handler))
 421                goto out;
 422
 423        retval = PyObject_CallObject(handler, NULL);
 424        if (retval == NULL)
 425                handler_call_die("trace_end");
 426        else
 427                Py_DECREF(retval);
 428out:
 429        Py_XDECREF(main_dict);
 430        Py_XDECREF(main_module);
 431        Py_Finalize();
 432
 433        return err;
 434}
 435
 436static int python_generate_script(const char *outfile)
 437{
 438        struct event *event = NULL;
 439        struct format_field *f;
 440        char fname[PATH_MAX];
 441        int not_first, count;
 442        FILE *ofp;
 443
 444        sprintf(fname, "%s.py", outfile);
 445        ofp = fopen(fname, "w");
 446        if (ofp == NULL) {
 447                fprintf(stderr, "couldn't open %s\n", fname);
 448                return -1;
 449        }
 450        fprintf(ofp, "# perf script event handlers, "
 451                "generated by perf script -g python\n");
 452
 453        fprintf(ofp, "# Licensed under the terms of the GNU GPL"
 454                " License version 2\n\n");
 455
 456        fprintf(ofp, "# The common_* event handler fields are the most useful "
 457                "fields common to\n");
 458
 459        fprintf(ofp, "# all events.  They don't necessarily correspond to "
 460                "the 'common_*' fields\n");
 461
 462        fprintf(ofp, "# in the format files.  Those fields not available as "
 463                "handler params can\n");
 464
 465        fprintf(ofp, "# be retrieved using Python functions of the form "
 466                "common_*(context).\n");
 467
 468        fprintf(ofp, "# See the perf-trace-python Documentation for the list "
 469                "of available functions.\n\n");
 470
 471        fprintf(ofp, "import os\n");
 472        fprintf(ofp, "import sys\n\n");
 473
 474        fprintf(ofp, "sys.path.append(os.environ['PERF_EXEC_PATH'] + \\\n");
 475        fprintf(ofp, "\t'/scripts/python/Perf-Trace-Util/lib/Perf/Trace')\n");
 476        fprintf(ofp, "\nfrom perf_trace_context import *\n");
 477        fprintf(ofp, "from Core import *\n\n\n");
 478
 479        fprintf(ofp, "def trace_begin():\n");
 480        fprintf(ofp, "\tprint \"in trace_begin\"\n\n");
 481
 482        fprintf(ofp, "def trace_end():\n");
 483        fprintf(ofp, "\tprint \"in trace_end\"\n\n");
 484
 485        while ((event = trace_find_next_event(event))) {
 486                fprintf(ofp, "def %s__%s(", event->system, event->name);
 487                fprintf(ofp, "event_name, ");
 488                fprintf(ofp, "context, ");
 489                fprintf(ofp, "common_cpu,\n");
 490                fprintf(ofp, "\tcommon_secs, ");
 491                fprintf(ofp, "common_nsecs, ");
 492                fprintf(ofp, "common_pid, ");
 493                fprintf(ofp, "common_comm,\n\t");
 494
 495                not_first = 0;
 496                count = 0;
 497
 498                for (f = event->format.fields; f; f = f->next) {
 499                        if (not_first++)
 500                                fprintf(ofp, ", ");
 501                        if (++count % 5 == 0)
 502                                fprintf(ofp, "\n\t");
 503
 504                        fprintf(ofp, "%s", f->name);
 505                }
 506                fprintf(ofp, "):\n");
 507
 508                fprintf(ofp, "\t\tprint_header(event_name, common_cpu, "
 509                        "common_secs, common_nsecs,\n\t\t\t"
 510                        "common_pid, common_comm)\n\n");
 511
 512                fprintf(ofp, "\t\tprint \"");
 513
 514                not_first = 0;
 515                count = 0;
 516
 517                for (f = event->format.fields; f; f = f->next) {
 518                        if (not_first++)
 519                                fprintf(ofp, ", ");
 520                        if (count && count % 3 == 0) {
 521                                fprintf(ofp, "\" \\\n\t\t\"");
 522                        }
 523                        count++;
 524
 525                        fprintf(ofp, "%s=", f->name);
 526                        if (f->flags & FIELD_IS_STRING ||
 527                            f->flags & FIELD_IS_FLAG ||
 528                            f->flags & FIELD_IS_SYMBOLIC)
 529                                fprintf(ofp, "%%s");
 530                        else if (f->flags & FIELD_IS_SIGNED)
 531                                fprintf(ofp, "%%d");
 532                        else
 533                                fprintf(ofp, "%%u");
 534                }
 535
 536                fprintf(ofp, "\\n\" %% \\\n\t\t(");
 537
 538                not_first = 0;
 539                count = 0;
 540
 541                for (f = event->format.fields; f; f = f->next) {
 542                        if (not_first++)
 543                                fprintf(ofp, ", ");
 544
 545                        if (++count % 5 == 0)
 546                                fprintf(ofp, "\n\t\t");
 547
 548                        if (f->flags & FIELD_IS_FLAG) {
 549                                if ((count - 1) % 5 != 0) {
 550                                        fprintf(ofp, "\n\t\t");
 551                                        count = 4;
 552                                }
 553                                fprintf(ofp, "flag_str(\"");
 554                                fprintf(ofp, "%s__%s\", ", event->system,
 555                                        event->name);
 556                                fprintf(ofp, "\"%s\", %s)", f->name,
 557                                        f->name);
 558                        } else if (f->flags & FIELD_IS_SYMBOLIC) {
 559                                if ((count - 1) % 5 != 0) {
 560                                        fprintf(ofp, "\n\t\t");
 561                                        count = 4;
 562                                }
 563                                fprintf(ofp, "symbol_str(\"");
 564                                fprintf(ofp, "%s__%s\", ", event->system,
 565                                        event->name);
 566                                fprintf(ofp, "\"%s\", %s)", f->name,
 567                                        f->name);
 568                        } else
 569                                fprintf(ofp, "%s", f->name);
 570                }
 571
 572                fprintf(ofp, "),\n\n");
 573        }
 574
 575        fprintf(ofp, "def trace_unhandled(event_name, context, "
 576                "event_fields_dict):\n");
 577
 578        fprintf(ofp, "\t\tprint ' '.join(['%%s=%%s'%%(k,str(v))"
 579                "for k,v in sorted(event_fields_dict.items())])\n\n");
 580
 581        fprintf(ofp, "def print_header("
 582                "event_name, cpu, secs, nsecs, pid, comm):\n"
 583                "\tprint \"%%-20s %%5u %%05u.%%09u %%8u %%-20s \" %% \\\n\t"
 584                "(event_name, cpu, secs, nsecs, pid, comm),\n");
 585
 586        fclose(ofp);
 587
 588        fprintf(stderr, "generated Python script: %s\n", fname);
 589
 590        return 0;
 591}
 592
 593struct scripting_ops python_scripting_ops = {
 594        .name = "Python",
 595        .start_script = python_start_script,
 596        .stop_script = python_stop_script,
 597        .process_event = python_process_event,
 598        .generate_script = python_generate_script,
 599};
 600