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 <errno.h>
28 
29 #include "../../perf.h"
30 #include "../util.h"
31 #include "../event.h"
32 #include "../thread.h"
33 #include "../trace-event.h"
34 
35 PyMODINIT_FUNC initperf_trace_context(void);
36 
37 #define FTRACE_MAX_EVENT				\
38 	((1 << (sizeof(unsigned short) * 8)) - 1)
39 
40 struct event *events[FTRACE_MAX_EVENT];
41 
42 #define MAX_FIELDS	64
43 #define N_COMMON_FIELDS	7
44 
45 extern struct scripting_context *scripting_context;
46 
47 static char *cur_field_name;
48 static int zero_flag_atom;
49 
50 static PyObject *main_module, *main_dict;
51 
handler_call_die(const char * handler_name)52 static void handler_call_die(const char *handler_name)
53 {
54 	PyErr_Print();
55 	Py_FatalError("problem in Python trace event handler");
56 }
57 
define_value(enum print_arg_type field_type,const char * ev_name,const char * field_name,const char * field_value,const char * field_str)58 static void define_value(enum print_arg_type field_type,
59 			 const char *ev_name,
60 			 const char *field_name,
61 			 const char *field_value,
62 			 const char *field_str)
63 {
64 	const char *handler_name = "define_flag_value";
65 	PyObject *handler, *t, *retval;
66 	unsigned long long value;
67 	unsigned n = 0;
68 
69 	if (field_type == PRINT_SYMBOL)
70 		handler_name = "define_symbolic_value";
71 
72 	t = PyTuple_New(4);
73 	if (!t)
74 		Py_FatalError("couldn't create Python tuple");
75 
76 	value = eval_flag(field_value);
77 
78 	PyTuple_SetItem(t, n++, PyString_FromString(ev_name));
79 	PyTuple_SetItem(t, n++, PyString_FromString(field_name));
80 	PyTuple_SetItem(t, n++, PyInt_FromLong(value));
81 	PyTuple_SetItem(t, n++, PyString_FromString(field_str));
82 
83 	handler = PyDict_GetItemString(main_dict, handler_name);
84 	if (handler && PyCallable_Check(handler)) {
85 		retval = PyObject_CallObject(handler, t);
86 		if (retval == NULL)
87 			handler_call_die(handler_name);
88 	}
89 
90 	Py_DECREF(t);
91 }
92 
define_values(enum print_arg_type field_type,struct print_flag_sym * field,const char * ev_name,const char * field_name)93 static void define_values(enum print_arg_type field_type,
94 			  struct print_flag_sym *field,
95 			  const char *ev_name,
96 			  const char *field_name)
97 {
98 	define_value(field_type, ev_name, field_name, field->value,
99 		     field->str);
100 
101 	if (field->next)
102 		define_values(field_type, field->next, ev_name, field_name);
103 }
104 
define_field(enum print_arg_type field_type,const char * ev_name,const char * field_name,const char * delim)105 static void define_field(enum print_arg_type field_type,
106 			 const char *ev_name,
107 			 const char *field_name,
108 			 const char *delim)
109 {
110 	const char *handler_name = "define_flag_field";
111 	PyObject *handler, *t, *retval;
112 	unsigned n = 0;
113 
114 	if (field_type == PRINT_SYMBOL)
115 		handler_name = "define_symbolic_field";
116 
117 	if (field_type == PRINT_FLAGS)
118 		t = PyTuple_New(3);
119 	else
120 		t = PyTuple_New(2);
121 	if (!t)
122 		Py_FatalError("couldn't create Python tuple");
123 
124 	PyTuple_SetItem(t, n++, PyString_FromString(ev_name));
125 	PyTuple_SetItem(t, n++, PyString_FromString(field_name));
126 	if (field_type == PRINT_FLAGS)
127 		PyTuple_SetItem(t, n++, PyString_FromString(delim));
128 
129 	handler = PyDict_GetItemString(main_dict, handler_name);
130 	if (handler && PyCallable_Check(handler)) {
131 		retval = PyObject_CallObject(handler, t);
132 		if (retval == NULL)
133 			handler_call_die(handler_name);
134 	}
135 
136 	Py_DECREF(t);
137 }
138 
define_event_symbols(struct event * event,const char * ev_name,struct print_arg * args)139 static void define_event_symbols(struct event *event,
140 				 const char *ev_name,
141 				 struct print_arg *args)
142 {
143 	switch (args->type) {
144 	case PRINT_NULL:
145 		break;
146 	case PRINT_ATOM:
147 		define_value(PRINT_FLAGS, ev_name, cur_field_name, "0",
148 			     args->atom.atom);
149 		zero_flag_atom = 0;
150 		break;
151 	case PRINT_FIELD:
152 		if (cur_field_name)
153 			free(cur_field_name);
154 		cur_field_name = strdup(args->field.name);
155 		break;
156 	case PRINT_FLAGS:
157 		define_event_symbols(event, ev_name, args->flags.field);
158 		define_field(PRINT_FLAGS, ev_name, cur_field_name,
159 			     args->flags.delim);
160 		define_values(PRINT_FLAGS, args->flags.flags, ev_name,
161 			      cur_field_name);
162 		break;
163 	case PRINT_SYMBOL:
164 		define_event_symbols(event, ev_name, args->symbol.field);
165 		define_field(PRINT_SYMBOL, ev_name, cur_field_name, NULL);
166 		define_values(PRINT_SYMBOL, args->symbol.symbols, ev_name,
167 			      cur_field_name);
168 		break;
169 	case PRINT_STRING:
170 		break;
171 	case PRINT_TYPE:
172 		define_event_symbols(event, ev_name, args->typecast.item);
173 		break;
174 	case PRINT_OP:
175 		if (strcmp(args->op.op, ":") == 0)
176 			zero_flag_atom = 1;
177 		define_event_symbols(event, ev_name, args->op.left);
178 		define_event_symbols(event, ev_name, args->op.right);
179 		break;
180 	default:
181 		/* we should warn... */
182 		return;
183 	}
184 
185 	if (args->next)
186 		define_event_symbols(event, ev_name, args->next);
187 }
188 
find_cache_event(int type)189 static inline struct event *find_cache_event(int type)
190 {
191 	static char ev_name[256];
192 	struct event *event;
193 
194 	if (events[type])
195 		return events[type];
196 
197 	events[type] = event = trace_find_event(type);
198 	if (!event)
199 		return NULL;
200 
201 	sprintf(ev_name, "%s__%s", event->system, event->name);
202 
203 	define_event_symbols(event, ev_name, event->print_fmt.args);
204 
205 	return event;
206 }
207 
python_process_event(union perf_event * pevent __unused,struct perf_sample * sample,struct perf_evsel * evsel __unused,struct machine * machine __unused,struct thread * thread)208 static void python_process_event(union perf_event *pevent __unused,
209 				 struct perf_sample *sample,
210 				 struct perf_evsel *evsel __unused,
211 				 struct machine *machine __unused,
212 				 struct thread *thread)
213 {
214 	PyObject *handler, *retval, *context, *t, *obj, *dict = NULL;
215 	static char handler_name[256];
216 	struct format_field *field;
217 	unsigned long long val;
218 	unsigned long s, ns;
219 	struct event *event;
220 	unsigned n = 0;
221 	int type;
222 	int pid;
223 	int cpu = sample->cpu;
224 	void *data = sample->raw_data;
225 	unsigned long long nsecs = sample->time;
226 	char *comm = thread->comm;
227 
228 	t = PyTuple_New(MAX_FIELDS);
229 	if (!t)
230 		Py_FatalError("couldn't create Python tuple");
231 
232 	type = trace_parse_common_type(data);
233 
234 	event = find_cache_event(type);
235 	if (!event)
236 		die("ug! no event found for type %d", type);
237 
238 	pid = trace_parse_common_pid(data);
239 
240 	sprintf(handler_name, "%s__%s", event->system, event->name);
241 
242 	handler = PyDict_GetItemString(main_dict, handler_name);
243 	if (handler && !PyCallable_Check(handler))
244 		handler = NULL;
245 	if (!handler) {
246 		dict = PyDict_New();
247 		if (!dict)
248 			Py_FatalError("couldn't create Python dict");
249 	}
250 	s = nsecs / NSECS_PER_SEC;
251 	ns = nsecs - s * NSECS_PER_SEC;
252 
253 	scripting_context->event_data = data;
254 
255 	context = PyCObject_FromVoidPtr(scripting_context, NULL);
256 
257 	PyTuple_SetItem(t, n++, PyString_FromString(handler_name));
258 	PyTuple_SetItem(t, n++, context);
259 
260 	if (handler) {
261 		PyTuple_SetItem(t, n++, PyInt_FromLong(cpu));
262 		PyTuple_SetItem(t, n++, PyInt_FromLong(s));
263 		PyTuple_SetItem(t, n++, PyInt_FromLong(ns));
264 		PyTuple_SetItem(t, n++, PyInt_FromLong(pid));
265 		PyTuple_SetItem(t, n++, PyString_FromString(comm));
266 	} else {
267 		PyDict_SetItemString(dict, "common_cpu", PyInt_FromLong(cpu));
268 		PyDict_SetItemString(dict, "common_s", PyInt_FromLong(s));
269 		PyDict_SetItemString(dict, "common_ns", PyInt_FromLong(ns));
270 		PyDict_SetItemString(dict, "common_pid", PyInt_FromLong(pid));
271 		PyDict_SetItemString(dict, "common_comm", PyString_FromString(comm));
272 	}
273 	for (field = event->format.fields; field; field = field->next) {
274 		if (field->flags & FIELD_IS_STRING) {
275 			int offset;
276 			if (field->flags & FIELD_IS_DYNAMIC) {
277 				offset = *(int *)(data + field->offset);
278 				offset &= 0xffff;
279 			} else
280 				offset = field->offset;
281 			obj = PyString_FromString((char *)data + offset);
282 		} else { /* FIELD_IS_NUMERIC */
283 			val = read_size(data + field->offset, field->size);
284 			if (field->flags & FIELD_IS_SIGNED) {
285 				if ((long long)val >= LONG_MIN &&
286 				    (long long)val <= LONG_MAX)
287 					obj = PyInt_FromLong(val);
288 				else
289 					obj = PyLong_FromLongLong(val);
290 			} else {
291 				if (val <= LONG_MAX)
292 					obj = PyInt_FromLong(val);
293 				else
294 					obj = PyLong_FromUnsignedLongLong(val);
295 			}
296 		}
297 		if (handler)
298 			PyTuple_SetItem(t, n++, obj);
299 		else
300 			PyDict_SetItemString(dict, field->name, obj);
301 
302 	}
303 	if (!handler)
304 		PyTuple_SetItem(t, n++, dict);
305 
306 	if (_PyTuple_Resize(&t, n) == -1)
307 		Py_FatalError("error resizing Python tuple");
308 
309 	if (handler) {
310 		retval = PyObject_CallObject(handler, t);
311 		if (retval == NULL)
312 			handler_call_die(handler_name);
313 	} else {
314 		handler = PyDict_GetItemString(main_dict, "trace_unhandled");
315 		if (handler && PyCallable_Check(handler)) {
316 
317 			retval = PyObject_CallObject(handler, t);
318 			if (retval == NULL)
319 				handler_call_die("trace_unhandled");
320 		}
321 		Py_DECREF(dict);
322 	}
323 
324 	Py_DECREF(t);
325 }
326 
run_start_sub(void)327 static int run_start_sub(void)
328 {
329 	PyObject *handler, *retval;
330 	int err = 0;
331 
332 	main_module = PyImport_AddModule("__main__");
333 	if (main_module == NULL)
334 		return -1;
335 	Py_INCREF(main_module);
336 
337 	main_dict = PyModule_GetDict(main_module);
338 	if (main_dict == NULL) {
339 		err = -1;
340 		goto error;
341 	}
342 	Py_INCREF(main_dict);
343 
344 	handler = PyDict_GetItemString(main_dict, "trace_begin");
345 	if (handler == NULL || !PyCallable_Check(handler))
346 		goto out;
347 
348 	retval = PyObject_CallObject(handler, NULL);
349 	if (retval == NULL)
350 		handler_call_die("trace_begin");
351 
352 	Py_DECREF(retval);
353 	return err;
354 error:
355 	Py_XDECREF(main_dict);
356 	Py_XDECREF(main_module);
357 out:
358 	return err;
359 }
360 
361 /*
362  * Start trace script
363  */
python_start_script(const char * script,int argc,const char ** argv)364 static int python_start_script(const char *script, int argc, const char **argv)
365 {
366 	const char **command_line;
367 	char buf[PATH_MAX];
368 	int i, err = 0;
369 	FILE *fp;
370 
371 	command_line = malloc((argc + 1) * sizeof(const char *));
372 	command_line[0] = script;
373 	for (i = 1; i < argc + 1; i++)
374 		command_line[i] = argv[i - 1];
375 
376 	Py_Initialize();
377 
378 	initperf_trace_context();
379 
380 	PySys_SetArgv(argc + 1, (char **)command_line);
381 
382 	fp = fopen(script, "r");
383 	if (!fp) {
384 		sprintf(buf, "Can't open python script \"%s\"", script);
385 		perror(buf);
386 		err = -1;
387 		goto error;
388 	}
389 
390 	err = PyRun_SimpleFile(fp, script);
391 	if (err) {
392 		fprintf(stderr, "Error running python script %s\n", script);
393 		goto error;
394 	}
395 
396 	err = run_start_sub();
397 	if (err) {
398 		fprintf(stderr, "Error starting python script %s\n", script);
399 		goto error;
400 	}
401 
402 	free(command_line);
403 
404 	return err;
405 error:
406 	Py_Finalize();
407 	free(command_line);
408 
409 	return err;
410 }
411 
412 /*
413  * Stop trace script
414  */
python_stop_script(void)415 static int python_stop_script(void)
416 {
417 	PyObject *handler, *retval;
418 	int err = 0;
419 
420 	handler = PyDict_GetItemString(main_dict, "trace_end");
421 	if (handler == NULL || !PyCallable_Check(handler))
422 		goto out;
423 
424 	retval = PyObject_CallObject(handler, NULL);
425 	if (retval == NULL)
426 		handler_call_die("trace_end");
427 	else
428 		Py_DECREF(retval);
429 out:
430 	Py_XDECREF(main_dict);
431 	Py_XDECREF(main_module);
432 	Py_Finalize();
433 
434 	return err;
435 }
436 
python_generate_script(const char * outfile)437 static int python_generate_script(const char *outfile)
438 {
439 	struct event *event = NULL;
440 	struct format_field *f;
441 	char fname[PATH_MAX];
442 	int not_first, count;
443 	FILE *ofp;
444 
445 	sprintf(fname, "%s.py", outfile);
446 	ofp = fopen(fname, "w");
447 	if (ofp == NULL) {
448 		fprintf(stderr, "couldn't open %s\n", fname);
449 		return -1;
450 	}
451 	fprintf(ofp, "# perf script event handlers, "
452 		"generated by perf script -g python\n");
453 
454 	fprintf(ofp, "# Licensed under the terms of the GNU GPL"
455 		" License version 2\n\n");
456 
457 	fprintf(ofp, "# The common_* event handler fields are the most useful "
458 		"fields common to\n");
459 
460 	fprintf(ofp, "# all events.  They don't necessarily correspond to "
461 		"the 'common_*' fields\n");
462 
463 	fprintf(ofp, "# in the format files.  Those fields not available as "
464 		"handler params can\n");
465 
466 	fprintf(ofp, "# be retrieved using Python functions of the form "
467 		"common_*(context).\n");
468 
469 	fprintf(ofp, "# See the perf-trace-python Documentation for the list "
470 		"of available functions.\n\n");
471 
472 	fprintf(ofp, "import os\n");
473 	fprintf(ofp, "import sys\n\n");
474 
475 	fprintf(ofp, "sys.path.append(os.environ['PERF_EXEC_PATH'] + \\\n");
476 	fprintf(ofp, "\t'/scripts/python/Perf-Trace-Util/lib/Perf/Trace')\n");
477 	fprintf(ofp, "\nfrom perf_trace_context import *\n");
478 	fprintf(ofp, "from Core import *\n\n\n");
479 
480 	fprintf(ofp, "def trace_begin():\n");
481 	fprintf(ofp, "\tprint \"in trace_begin\"\n\n");
482 
483 	fprintf(ofp, "def trace_end():\n");
484 	fprintf(ofp, "\tprint \"in trace_end\"\n\n");
485 
486 	while ((event = trace_find_next_event(event))) {
487 		fprintf(ofp, "def %s__%s(", event->system, event->name);
488 		fprintf(ofp, "event_name, ");
489 		fprintf(ofp, "context, ");
490 		fprintf(ofp, "common_cpu,\n");
491 		fprintf(ofp, "\tcommon_secs, ");
492 		fprintf(ofp, "common_nsecs, ");
493 		fprintf(ofp, "common_pid, ");
494 		fprintf(ofp, "common_comm,\n\t");
495 
496 		not_first = 0;
497 		count = 0;
498 
499 		for (f = event->format.fields; f; f = f->next) {
500 			if (not_first++)
501 				fprintf(ofp, ", ");
502 			if (++count % 5 == 0)
503 				fprintf(ofp, "\n\t");
504 
505 			fprintf(ofp, "%s", f->name);
506 		}
507 		fprintf(ofp, "):\n");
508 
509 		fprintf(ofp, "\t\tprint_header(event_name, common_cpu, "
510 			"common_secs, common_nsecs,\n\t\t\t"
511 			"common_pid, common_comm)\n\n");
512 
513 		fprintf(ofp, "\t\tprint \"");
514 
515 		not_first = 0;
516 		count = 0;
517 
518 		for (f = event->format.fields; f; f = f->next) {
519 			if (not_first++)
520 				fprintf(ofp, ", ");
521 			if (count && count % 3 == 0) {
522 				fprintf(ofp, "\" \\\n\t\t\"");
523 			}
524 			count++;
525 
526 			fprintf(ofp, "%s=", f->name);
527 			if (f->flags & FIELD_IS_STRING ||
528 			    f->flags & FIELD_IS_FLAG ||
529 			    f->flags & FIELD_IS_SYMBOLIC)
530 				fprintf(ofp, "%%s");
531 			else if (f->flags & FIELD_IS_SIGNED)
532 				fprintf(ofp, "%%d");
533 			else
534 				fprintf(ofp, "%%u");
535 		}
536 
537 		fprintf(ofp, "\\n\" %% \\\n\t\t(");
538 
539 		not_first = 0;
540 		count = 0;
541 
542 		for (f = event->format.fields; f; f = f->next) {
543 			if (not_first++)
544 				fprintf(ofp, ", ");
545 
546 			if (++count % 5 == 0)
547 				fprintf(ofp, "\n\t\t");
548 
549 			if (f->flags & FIELD_IS_FLAG) {
550 				if ((count - 1) % 5 != 0) {
551 					fprintf(ofp, "\n\t\t");
552 					count = 4;
553 				}
554 				fprintf(ofp, "flag_str(\"");
555 				fprintf(ofp, "%s__%s\", ", event->system,
556 					event->name);
557 				fprintf(ofp, "\"%s\", %s)", f->name,
558 					f->name);
559 			} else if (f->flags & FIELD_IS_SYMBOLIC) {
560 				if ((count - 1) % 5 != 0) {
561 					fprintf(ofp, "\n\t\t");
562 					count = 4;
563 				}
564 				fprintf(ofp, "symbol_str(\"");
565 				fprintf(ofp, "%s__%s\", ", event->system,
566 					event->name);
567 				fprintf(ofp, "\"%s\", %s)", f->name,
568 					f->name);
569 			} else
570 				fprintf(ofp, "%s", f->name);
571 		}
572 
573 		fprintf(ofp, "),\n\n");
574 	}
575 
576 	fprintf(ofp, "def trace_unhandled(event_name, context, "
577 		"event_fields_dict):\n");
578 
579 	fprintf(ofp, "\t\tprint ' '.join(['%%s=%%s'%%(k,str(v))"
580 		"for k,v in sorted(event_fields_dict.items())])\n\n");
581 
582 	fprintf(ofp, "def print_header("
583 		"event_name, cpu, secs, nsecs, pid, comm):\n"
584 		"\tprint \"%%-20s %%5u %%05u.%%09u %%8u %%-20s \" %% \\\n\t"
585 		"(event_name, cpu, secs, nsecs, pid, comm),\n");
586 
587 	fclose(ofp);
588 
589 	fprintf(stderr, "generated Python script: %s\n", fname);
590 
591 	return 0;
592 }
593 
594 struct scripting_ops python_scripting_ops = {
595 	.name = "Python",
596 	.start_script = python_start_script,
597 	.stop_script = python_stop_script,
598 	.process_event = python_process_event,
599 	.generate_script = python_generate_script,
600 };
601