1 /*
2  * trace-event-perl.  Feed perf script events to an embedded Perl interpreter.
3  *
4  * Copyright (C) 2009 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 <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <ctype.h>
26 #include <errno.h>
27 
28 #include "../util.h"
29 #include <EXTERN.h>
30 #include <perl.h>
31 
32 #include "../../perf.h"
33 #include "../thread.h"
34 #include "../event.h"
35 #include "../trace-event.h"
36 #include "../evsel.h"
37 
38 void boot_Perf__Trace__Context(pTHX_ CV *cv);
39 void boot_DynaLoader(pTHX_ CV *cv);
40 typedef PerlInterpreter * INTERP;
41 
42 void xs_init(pTHX);
43 
44 void xs_init(pTHX)
45 {
46 	const char *file = __FILE__;
47 	dXSUB_SYS;
48 
49 	newXS("Perf::Trace::Context::bootstrap", boot_Perf__Trace__Context,
50 	      file);
51 	newXS("DynaLoader::boot_DynaLoader", boot_DynaLoader, file);
52 }
53 
54 INTERP my_perl;
55 
56 #define FTRACE_MAX_EVENT				\
57 	((1 << (sizeof(unsigned short) * 8)) - 1)
58 
59 struct event_format *events[FTRACE_MAX_EVENT];
60 
61 extern struct scripting_context *scripting_context;
62 
63 static char *cur_field_name;
64 static int zero_flag_atom;
65 
66 static void define_symbolic_value(const char *ev_name,
67 				  const char *field_name,
68 				  const char *field_value,
69 				  const char *field_str)
70 {
71 	unsigned long long value;
72 	dSP;
73 
74 	value = eval_flag(field_value);
75 
76 	ENTER;
77 	SAVETMPS;
78 	PUSHMARK(SP);
79 
80 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
81 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
82 	XPUSHs(sv_2mortal(newSVuv(value)));
83 	XPUSHs(sv_2mortal(newSVpv(field_str, 0)));
84 
85 	PUTBACK;
86 	if (get_cv("main::define_symbolic_value", 0))
87 		call_pv("main::define_symbolic_value", G_SCALAR);
88 	SPAGAIN;
89 	PUTBACK;
90 	FREETMPS;
91 	LEAVE;
92 }
93 
94 static void define_symbolic_values(struct print_flag_sym *field,
95 				   const char *ev_name,
96 				   const char *field_name)
97 {
98 	define_symbolic_value(ev_name, field_name, field->value, field->str);
99 	if (field->next)
100 		define_symbolic_values(field->next, ev_name, field_name);
101 }
102 
103 static void define_symbolic_field(const char *ev_name,
104 				  const char *field_name)
105 {
106 	dSP;
107 
108 	ENTER;
109 	SAVETMPS;
110 	PUSHMARK(SP);
111 
112 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
113 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
114 
115 	PUTBACK;
116 	if (get_cv("main::define_symbolic_field", 0))
117 		call_pv("main::define_symbolic_field", G_SCALAR);
118 	SPAGAIN;
119 	PUTBACK;
120 	FREETMPS;
121 	LEAVE;
122 }
123 
124 static void define_flag_value(const char *ev_name,
125 			      const char *field_name,
126 			      const char *field_value,
127 			      const char *field_str)
128 {
129 	unsigned long long value;
130 	dSP;
131 
132 	value = eval_flag(field_value);
133 
134 	ENTER;
135 	SAVETMPS;
136 	PUSHMARK(SP);
137 
138 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
139 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
140 	XPUSHs(sv_2mortal(newSVuv(value)));
141 	XPUSHs(sv_2mortal(newSVpv(field_str, 0)));
142 
143 	PUTBACK;
144 	if (get_cv("main::define_flag_value", 0))
145 		call_pv("main::define_flag_value", G_SCALAR);
146 	SPAGAIN;
147 	PUTBACK;
148 	FREETMPS;
149 	LEAVE;
150 }
151 
152 static void define_flag_values(struct print_flag_sym *field,
153 			       const char *ev_name,
154 			       const char *field_name)
155 {
156 	define_flag_value(ev_name, field_name, field->value, field->str);
157 	if (field->next)
158 		define_flag_values(field->next, ev_name, field_name);
159 }
160 
161 static void define_flag_field(const char *ev_name,
162 			      const char *field_name,
163 			      const char *delim)
164 {
165 	dSP;
166 
167 	ENTER;
168 	SAVETMPS;
169 	PUSHMARK(SP);
170 
171 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
172 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
173 	XPUSHs(sv_2mortal(newSVpv(delim, 0)));
174 
175 	PUTBACK;
176 	if (get_cv("main::define_flag_field", 0))
177 		call_pv("main::define_flag_field", G_SCALAR);
178 	SPAGAIN;
179 	PUTBACK;
180 	FREETMPS;
181 	LEAVE;
182 }
183 
184 static void define_event_symbols(struct event_format *event,
185 				 const char *ev_name,
186 				 struct print_arg *args)
187 {
188 	switch (args->type) {
189 	case PRINT_NULL:
190 		break;
191 	case PRINT_ATOM:
192 		define_flag_value(ev_name, cur_field_name, "0",
193 				  args->atom.atom);
194 		zero_flag_atom = 0;
195 		break;
196 	case PRINT_FIELD:
197 		if (cur_field_name)
198 			free(cur_field_name);
199 		cur_field_name = strdup(args->field.name);
200 		break;
201 	case PRINT_FLAGS:
202 		define_event_symbols(event, ev_name, args->flags.field);
203 		define_flag_field(ev_name, cur_field_name, args->flags.delim);
204 		define_flag_values(args->flags.flags, ev_name, cur_field_name);
205 		break;
206 	case PRINT_SYMBOL:
207 		define_event_symbols(event, ev_name, args->symbol.field);
208 		define_symbolic_field(ev_name, cur_field_name);
209 		define_symbolic_values(args->symbol.symbols, ev_name,
210 				       cur_field_name);
211 		break;
212 	case PRINT_HEX:
213 		define_event_symbols(event, ev_name, args->hex.field);
214 		define_event_symbols(event, ev_name, args->hex.size);
215 		break;
216 	case PRINT_BSTRING:
217 	case PRINT_DYNAMIC_ARRAY:
218 	case PRINT_STRING:
219 		break;
220 	case PRINT_TYPE:
221 		define_event_symbols(event, ev_name, args->typecast.item);
222 		break;
223 	case PRINT_OP:
224 		if (strcmp(args->op.op, ":") == 0)
225 			zero_flag_atom = 1;
226 		define_event_symbols(event, ev_name, args->op.left);
227 		define_event_symbols(event, ev_name, args->op.right);
228 		break;
229 	case PRINT_FUNC:
230 	default:
231 		pr_err("Unsupported print arg type\n");
232 		/* we should warn... */
233 		return;
234 	}
235 
236 	if (args->next)
237 		define_event_symbols(event, ev_name, args->next);
238 }
239 
240 static inline struct event_format *find_cache_event(struct perf_evsel *evsel)
241 {
242 	static char ev_name[256];
243 	struct event_format *event;
244 	int type = evsel->attr.config;
245 
246 	if (events[type])
247 		return events[type];
248 
249 	events[type] = event = evsel->tp_format;
250 	if (!event)
251 		return NULL;
252 
253 	sprintf(ev_name, "%s::%s", event->system, event->name);
254 
255 	define_event_symbols(event, ev_name, event->print_fmt.args);
256 
257 	return event;
258 }
259 
260 static void perl_process_tracepoint(union perf_event *perf_event __maybe_unused,
261 				    struct perf_sample *sample,
262 				    struct perf_evsel *evsel,
263 				    struct machine *machine __maybe_unused,
264 				    struct thread *thread,
265 					struct addr_location *al)
266 {
267 	struct format_field *field;
268 	static char handler[256];
269 	unsigned long long val;
270 	unsigned long s, ns;
271 	struct event_format *event;
272 	int pid;
273 	int cpu = sample->cpu;
274 	void *data = sample->raw_data;
275 	unsigned long long nsecs = sample->time;
276 	const char *comm = thread__comm_str(thread);
277 
278 	dSP;
279 
280 	if (evsel->attr.type != PERF_TYPE_TRACEPOINT)
281 		return;
282 
283 	event = find_cache_event(evsel);
284 	if (!event)
285 		die("ug! no event found for type %" PRIu64, (u64)evsel->attr.config);
286 
287 	pid = raw_field_value(event, "common_pid", data);
288 
289 	sprintf(handler, "%s::%s", event->system, event->name);
290 
291 	s = nsecs / NSECS_PER_SEC;
292 	ns = nsecs - s * NSECS_PER_SEC;
293 
294 	scripting_context->event_data = data;
295 	scripting_context->pevent = evsel->tp_format->pevent;
296 
297 	ENTER;
298 	SAVETMPS;
299 	PUSHMARK(SP);
300 
301 	XPUSHs(sv_2mortal(newSVpv(handler, 0)));
302 	XPUSHs(sv_2mortal(newSViv(PTR2IV(scripting_context))));
303 	XPUSHs(sv_2mortal(newSVuv(cpu)));
304 	XPUSHs(sv_2mortal(newSVuv(s)));
305 	XPUSHs(sv_2mortal(newSVuv(ns)));
306 	XPUSHs(sv_2mortal(newSViv(pid)));
307 	XPUSHs(sv_2mortal(newSVpv(comm, 0)));
308 
309 	/* common fields other than pid can be accessed via xsub fns */
310 
311 	for (field = event->format.fields; field; field = field->next) {
312 		if (field->flags & FIELD_IS_STRING) {
313 			int offset;
314 			if (field->flags & FIELD_IS_DYNAMIC) {
315 				offset = *(int *)(data + field->offset);
316 				offset &= 0xffff;
317 			} else
318 				offset = field->offset;
319 			XPUSHs(sv_2mortal(newSVpv((char *)data + offset, 0)));
320 		} else { /* FIELD_IS_NUMERIC */
321 			val = read_size(event, data + field->offset,
322 					field->size);
323 			if (field->flags & FIELD_IS_SIGNED) {
324 				XPUSHs(sv_2mortal(newSViv(val)));
325 			} else {
326 				XPUSHs(sv_2mortal(newSVuv(val)));
327 			}
328 		}
329 	}
330 
331 	PUTBACK;
332 
333 	if (get_cv(handler, 0))
334 		call_pv(handler, G_SCALAR);
335 	else if (get_cv("main::trace_unhandled", 0)) {
336 		XPUSHs(sv_2mortal(newSVpv(handler, 0)));
337 		XPUSHs(sv_2mortal(newSViv(PTR2IV(scripting_context))));
338 		XPUSHs(sv_2mortal(newSVuv(cpu)));
339 		XPUSHs(sv_2mortal(newSVuv(nsecs)));
340 		XPUSHs(sv_2mortal(newSViv(pid)));
341 		XPUSHs(sv_2mortal(newSVpv(comm, 0)));
342 		call_pv("main::trace_unhandled", G_SCALAR);
343 	}
344 	SPAGAIN;
345 	PUTBACK;
346 	FREETMPS;
347 	LEAVE;
348 }
349 
350 static void perl_process_event_generic(union perf_event *event,
351 				       struct perf_sample *sample,
352 				       struct perf_evsel *evsel,
353 				       struct machine *machine __maybe_unused,
354 				       struct thread *thread __maybe_unused,
355 					   struct addr_location *al __maybe_unused)
356 {
357 	dSP;
358 
359 	if (!get_cv("process_event", 0))
360 		return;
361 
362 	ENTER;
363 	SAVETMPS;
364 	PUSHMARK(SP);
365 	XPUSHs(sv_2mortal(newSVpvn((const char *)event, event->header.size)));
366 	XPUSHs(sv_2mortal(newSVpvn((const char *)&evsel->attr, sizeof(evsel->attr))));
367 	XPUSHs(sv_2mortal(newSVpvn((const char *)sample, sizeof(*sample))));
368 	XPUSHs(sv_2mortal(newSVpvn((const char *)sample->raw_data, sample->raw_size)));
369 	PUTBACK;
370 	call_pv("process_event", G_SCALAR);
371 	SPAGAIN;
372 	PUTBACK;
373 	FREETMPS;
374 	LEAVE;
375 }
376 
377 static void perl_process_event(union perf_event *event,
378 			       struct perf_sample *sample,
379 			       struct perf_evsel *evsel,
380 			       struct machine *machine,
381 			       struct thread *thread,
382 				   struct addr_location *al)
383 {
384 	perl_process_tracepoint(event, sample, evsel, machine, thread, al);
385 	perl_process_event_generic(event, sample, evsel, machine, thread, al);
386 }
387 
388 static void run_start_sub(void)
389 {
390 	dSP; /* access to Perl stack */
391 	PUSHMARK(SP);
392 
393 	if (get_cv("main::trace_begin", 0))
394 		call_pv("main::trace_begin", G_DISCARD | G_NOARGS);
395 }
396 
397 /*
398  * Start trace script
399  */
400 static int perl_start_script(const char *script, int argc, const char **argv)
401 {
402 	const char **command_line;
403 	int i, err = 0;
404 
405 	command_line = malloc((argc + 2) * sizeof(const char *));
406 	command_line[0] = "";
407 	command_line[1] = script;
408 	for (i = 2; i < argc + 2; i++)
409 		command_line[i] = argv[i - 2];
410 
411 	my_perl = perl_alloc();
412 	perl_construct(my_perl);
413 
414 	if (perl_parse(my_perl, xs_init, argc + 2, (char **)command_line,
415 		       (char **)NULL)) {
416 		err = -1;
417 		goto error;
418 	}
419 
420 	if (perl_run(my_perl)) {
421 		err = -1;
422 		goto error;
423 	}
424 
425 	if (SvTRUE(ERRSV)) {
426 		err = -1;
427 		goto error;
428 	}
429 
430 	run_start_sub();
431 
432 	free(command_line);
433 	return 0;
434 error:
435 	perl_free(my_perl);
436 	free(command_line);
437 
438 	return err;
439 }
440 
441 /*
442  * Stop trace script
443  */
444 static int perl_stop_script(void)
445 {
446 	dSP; /* access to Perl stack */
447 	PUSHMARK(SP);
448 
449 	if (get_cv("main::trace_end", 0))
450 		call_pv("main::trace_end", G_DISCARD | G_NOARGS);
451 
452 	perl_destruct(my_perl);
453 	perl_free(my_perl);
454 
455 	return 0;
456 }
457 
458 static int perl_generate_script(struct pevent *pevent, const char *outfile)
459 {
460 	struct event_format *event = NULL;
461 	struct format_field *f;
462 	char fname[PATH_MAX];
463 	int not_first, count;
464 	FILE *ofp;
465 
466 	sprintf(fname, "%s.pl", outfile);
467 	ofp = fopen(fname, "w");
468 	if (ofp == NULL) {
469 		fprintf(stderr, "couldn't open %s\n", fname);
470 		return -1;
471 	}
472 
473 	fprintf(ofp, "# perf script event handlers, "
474 		"generated by perf script -g perl\n");
475 
476 	fprintf(ofp, "# Licensed under the terms of the GNU GPL"
477 		" License version 2\n\n");
478 
479 	fprintf(ofp, "# The common_* event handler fields are the most useful "
480 		"fields common to\n");
481 
482 	fprintf(ofp, "# all events.  They don't necessarily correspond to "
483 		"the 'common_*' fields\n");
484 
485 	fprintf(ofp, "# in the format files.  Those fields not available as "
486 		"handler params can\n");
487 
488 	fprintf(ofp, "# be retrieved using Perl functions of the form "
489 		"common_*($context).\n");
490 
491 	fprintf(ofp, "# See Context.pm for the list of available "
492 		"functions.\n\n");
493 
494 	fprintf(ofp, "use lib \"$ENV{'PERF_EXEC_PATH'}/scripts/perl/"
495 		"Perf-Trace-Util/lib\";\n");
496 
497 	fprintf(ofp, "use lib \"./Perf-Trace-Util/lib\";\n");
498 	fprintf(ofp, "use Perf::Trace::Core;\n");
499 	fprintf(ofp, "use Perf::Trace::Context;\n");
500 	fprintf(ofp, "use Perf::Trace::Util;\n\n");
501 
502 	fprintf(ofp, "sub trace_begin\n{\n\t# optional\n}\n\n");
503 	fprintf(ofp, "sub trace_end\n{\n\t# optional\n}\n\n");
504 
505 	while ((event = trace_find_next_event(pevent, event))) {
506 		fprintf(ofp, "sub %s::%s\n{\n", event->system, event->name);
507 		fprintf(ofp, "\tmy (");
508 
509 		fprintf(ofp, "$event_name, ");
510 		fprintf(ofp, "$context, ");
511 		fprintf(ofp, "$common_cpu, ");
512 		fprintf(ofp, "$common_secs, ");
513 		fprintf(ofp, "$common_nsecs,\n");
514 		fprintf(ofp, "\t    $common_pid, ");
515 		fprintf(ofp, "$common_comm,\n\t    ");
516 
517 		not_first = 0;
518 		count = 0;
519 
520 		for (f = event->format.fields; f; f = f->next) {
521 			if (not_first++)
522 				fprintf(ofp, ", ");
523 			if (++count % 5 == 0)
524 				fprintf(ofp, "\n\t    ");
525 
526 			fprintf(ofp, "$%s", f->name);
527 		}
528 		fprintf(ofp, ") = @_;\n\n");
529 
530 		fprintf(ofp, "\tprint_header($event_name, $common_cpu, "
531 			"$common_secs, $common_nsecs,\n\t             "
532 			"$common_pid, $common_comm);\n\n");
533 
534 		fprintf(ofp, "\tprintf(\"");
535 
536 		not_first = 0;
537 		count = 0;
538 
539 		for (f = event->format.fields; f; f = f->next) {
540 			if (not_first++)
541 				fprintf(ofp, ", ");
542 			if (count && count % 4 == 0) {
543 				fprintf(ofp, "\".\n\t       \"");
544 			}
545 			count++;
546 
547 			fprintf(ofp, "%s=", f->name);
548 			if (f->flags & FIELD_IS_STRING ||
549 			    f->flags & FIELD_IS_FLAG ||
550 			    f->flags & FIELD_IS_SYMBOLIC)
551 				fprintf(ofp, "%%s");
552 			else if (f->flags & FIELD_IS_SIGNED)
553 				fprintf(ofp, "%%d");
554 			else
555 				fprintf(ofp, "%%u");
556 		}
557 
558 		fprintf(ofp, "\\n\",\n\t       ");
559 
560 		not_first = 0;
561 		count = 0;
562 
563 		for (f = event->format.fields; f; f = f->next) {
564 			if (not_first++)
565 				fprintf(ofp, ", ");
566 
567 			if (++count % 5 == 0)
568 				fprintf(ofp, "\n\t       ");
569 
570 			if (f->flags & FIELD_IS_FLAG) {
571 				if ((count - 1) % 5 != 0) {
572 					fprintf(ofp, "\n\t       ");
573 					count = 4;
574 				}
575 				fprintf(ofp, "flag_str(\"");
576 				fprintf(ofp, "%s::%s\", ", event->system,
577 					event->name);
578 				fprintf(ofp, "\"%s\", $%s)", f->name,
579 					f->name);
580 			} else if (f->flags & FIELD_IS_SYMBOLIC) {
581 				if ((count - 1) % 5 != 0) {
582 					fprintf(ofp, "\n\t       ");
583 					count = 4;
584 				}
585 				fprintf(ofp, "symbol_str(\"");
586 				fprintf(ofp, "%s::%s\", ", event->system,
587 					event->name);
588 				fprintf(ofp, "\"%s\", $%s)", f->name,
589 					f->name);
590 			} else
591 				fprintf(ofp, "$%s", f->name);
592 		}
593 
594 		fprintf(ofp, ");\n");
595 		fprintf(ofp, "}\n\n");
596 	}
597 
598 	fprintf(ofp, "sub trace_unhandled\n{\n\tmy ($event_name, $context, "
599 		"$common_cpu, $common_secs, $common_nsecs,\n\t    "
600 		"$common_pid, $common_comm) = @_;\n\n");
601 
602 	fprintf(ofp, "\tprint_header($event_name, $common_cpu, "
603 		"$common_secs, $common_nsecs,\n\t             $common_pid, "
604 		"$common_comm);\n}\n\n");
605 
606 	fprintf(ofp, "sub print_header\n{\n"
607 		"\tmy ($event_name, $cpu, $secs, $nsecs, $pid, $comm) = @_;\n\n"
608 		"\tprintf(\"%%-20s %%5u %%05u.%%09u %%8u %%-20s \",\n\t       "
609 		"$event_name, $cpu, $secs, $nsecs, $pid, $comm);\n}\n");
610 
611 	fprintf(ofp,
612 		"\n# Packed byte string args of process_event():\n"
613 		"#\n"
614 		"# $event:\tunion perf_event\tutil/event.h\n"
615 		"# $attr:\tstruct perf_event_attr\tlinux/perf_event.h\n"
616 		"# $sample:\tstruct perf_sample\tutil/event.h\n"
617 		"# $raw_data:\tperf_sample->raw_data\tutil/event.h\n"
618 		"\n"
619 		"sub process_event\n"
620 		"{\n"
621 		"\tmy ($event, $attr, $sample, $raw_data) = @_;\n"
622 		"\n"
623 		"\tmy @event\t= unpack(\"LSS\", $event);\n"
624 		"\tmy @attr\t= unpack(\"LLQQQQQLLQQ\", $attr);\n"
625 		"\tmy @sample\t= unpack(\"QLLQQQQQLL\", $sample);\n"
626 		"\tmy @raw_data\t= unpack(\"C*\", $raw_data);\n"
627 		"\n"
628 		"\tuse Data::Dumper;\n"
629 		"\tprint Dumper \\@event, \\@attr, \\@sample, \\@raw_data;\n"
630 		"}\n");
631 
632 	fclose(ofp);
633 
634 	fprintf(stderr, "generated Perl script: %s\n", fname);
635 
636 	return 0;
637 }
638 
639 struct scripting_ops perl_scripting_ops = {
640 	.name = "Perl",
641 	.start_script = perl_start_script,
642 	.stop_script = perl_stop_script,
643 	.process_event = perl_process_event,
644 	.generate_script = perl_generate_script,
645 };
646