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 <inttypes.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26 #include <ctype.h>
27 #include <errno.h>
28 #include <linux/bitmap.h>
29 #include <linux/time64.h>
30 
31 #include <stdbool.h>
32 /* perl needs the following define, right after including stdbool.h */
33 #define HAS_BOOL
34 #include <EXTERN.h>
35 #include <perl.h>
36 
37 #include "../../perf.h"
38 #include "../callchain.h"
39 #include "../machine.h"
40 #include "../thread.h"
41 #include "../event.h"
42 #include "../trace-event.h"
43 #include "../evsel.h"
44 #include "../debug.h"
45 
46 void boot_Perf__Trace__Context(pTHX_ CV *cv);
47 void boot_DynaLoader(pTHX_ CV *cv);
48 typedef PerlInterpreter * INTERP;
49 
50 void xs_init(pTHX);
51 
52 void xs_init(pTHX)
53 {
54 	const char *file = __FILE__;
55 	dXSUB_SYS;
56 
57 	newXS("Perf::Trace::Context::bootstrap", boot_Perf__Trace__Context,
58 	      file);
59 	newXS("DynaLoader::boot_DynaLoader", boot_DynaLoader, file);
60 }
61 
62 INTERP my_perl;
63 
64 #define TRACE_EVENT_TYPE_MAX				\
65 	((1 << (sizeof(unsigned short) * 8)) - 1)
66 
67 static DECLARE_BITMAP(events_defined, TRACE_EVENT_TYPE_MAX);
68 
69 extern struct scripting_context *scripting_context;
70 
71 static char *cur_field_name;
72 static int zero_flag_atom;
73 
74 static void define_symbolic_value(const char *ev_name,
75 				  const char *field_name,
76 				  const char *field_value,
77 				  const char *field_str)
78 {
79 	unsigned long long value;
80 	dSP;
81 
82 	value = eval_flag(field_value);
83 
84 	ENTER;
85 	SAVETMPS;
86 	PUSHMARK(SP);
87 
88 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
89 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
90 	XPUSHs(sv_2mortal(newSVuv(value)));
91 	XPUSHs(sv_2mortal(newSVpv(field_str, 0)));
92 
93 	PUTBACK;
94 	if (get_cv("main::define_symbolic_value", 0))
95 		call_pv("main::define_symbolic_value", G_SCALAR);
96 	SPAGAIN;
97 	PUTBACK;
98 	FREETMPS;
99 	LEAVE;
100 }
101 
102 static void define_symbolic_values(struct tep_print_flag_sym *field,
103 				   const char *ev_name,
104 				   const char *field_name)
105 {
106 	define_symbolic_value(ev_name, field_name, field->value, field->str);
107 	if (field->next)
108 		define_symbolic_values(field->next, ev_name, field_name);
109 }
110 
111 static void define_symbolic_field(const char *ev_name,
112 				  const char *field_name)
113 {
114 	dSP;
115 
116 	ENTER;
117 	SAVETMPS;
118 	PUSHMARK(SP);
119 
120 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
121 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
122 
123 	PUTBACK;
124 	if (get_cv("main::define_symbolic_field", 0))
125 		call_pv("main::define_symbolic_field", G_SCALAR);
126 	SPAGAIN;
127 	PUTBACK;
128 	FREETMPS;
129 	LEAVE;
130 }
131 
132 static void define_flag_value(const char *ev_name,
133 			      const char *field_name,
134 			      const char *field_value,
135 			      const char *field_str)
136 {
137 	unsigned long long value;
138 	dSP;
139 
140 	value = eval_flag(field_value);
141 
142 	ENTER;
143 	SAVETMPS;
144 	PUSHMARK(SP);
145 
146 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
147 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
148 	XPUSHs(sv_2mortal(newSVuv(value)));
149 	XPUSHs(sv_2mortal(newSVpv(field_str, 0)));
150 
151 	PUTBACK;
152 	if (get_cv("main::define_flag_value", 0))
153 		call_pv("main::define_flag_value", G_SCALAR);
154 	SPAGAIN;
155 	PUTBACK;
156 	FREETMPS;
157 	LEAVE;
158 }
159 
160 static void define_flag_values(struct tep_print_flag_sym *field,
161 			       const char *ev_name,
162 			       const char *field_name)
163 {
164 	define_flag_value(ev_name, field_name, field->value, field->str);
165 	if (field->next)
166 		define_flag_values(field->next, ev_name, field_name);
167 }
168 
169 static void define_flag_field(const char *ev_name,
170 			      const char *field_name,
171 			      const char *delim)
172 {
173 	dSP;
174 
175 	ENTER;
176 	SAVETMPS;
177 	PUSHMARK(SP);
178 
179 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
180 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
181 	XPUSHs(sv_2mortal(newSVpv(delim, 0)));
182 
183 	PUTBACK;
184 	if (get_cv("main::define_flag_field", 0))
185 		call_pv("main::define_flag_field", G_SCALAR);
186 	SPAGAIN;
187 	PUTBACK;
188 	FREETMPS;
189 	LEAVE;
190 }
191 
192 static void define_event_symbols(struct tep_event_format *event,
193 				 const char *ev_name,
194 				 struct tep_print_arg *args)
195 {
196 	if (args == NULL)
197 		return;
198 
199 	switch (args->type) {
200 	case TEP_PRINT_NULL:
201 		break;
202 	case TEP_PRINT_ATOM:
203 		define_flag_value(ev_name, cur_field_name, "0",
204 				  args->atom.atom);
205 		zero_flag_atom = 0;
206 		break;
207 	case TEP_PRINT_FIELD:
208 		free(cur_field_name);
209 		cur_field_name = strdup(args->field.name);
210 		break;
211 	case TEP_PRINT_FLAGS:
212 		define_event_symbols(event, ev_name, args->flags.field);
213 		define_flag_field(ev_name, cur_field_name, args->flags.delim);
214 		define_flag_values(args->flags.flags, ev_name, cur_field_name);
215 		break;
216 	case TEP_PRINT_SYMBOL:
217 		define_event_symbols(event, ev_name, args->symbol.field);
218 		define_symbolic_field(ev_name, cur_field_name);
219 		define_symbolic_values(args->symbol.symbols, ev_name,
220 				       cur_field_name);
221 		break;
222 	case TEP_PRINT_HEX:
223 	case TEP_PRINT_HEX_STR:
224 		define_event_symbols(event, ev_name, args->hex.field);
225 		define_event_symbols(event, ev_name, args->hex.size);
226 		break;
227 	case TEP_PRINT_INT_ARRAY:
228 		define_event_symbols(event, ev_name, args->int_array.field);
229 		define_event_symbols(event, ev_name, args->int_array.count);
230 		define_event_symbols(event, ev_name, args->int_array.el_size);
231 		break;
232 	case TEP_PRINT_BSTRING:
233 	case TEP_PRINT_DYNAMIC_ARRAY:
234 	case TEP_PRINT_DYNAMIC_ARRAY_LEN:
235 	case TEP_PRINT_STRING:
236 	case TEP_PRINT_BITMASK:
237 		break;
238 	case TEP_PRINT_TYPE:
239 		define_event_symbols(event, ev_name, args->typecast.item);
240 		break;
241 	case TEP_PRINT_OP:
242 		if (strcmp(args->op.op, ":") == 0)
243 			zero_flag_atom = 1;
244 		define_event_symbols(event, ev_name, args->op.left);
245 		define_event_symbols(event, ev_name, args->op.right);
246 		break;
247 	case TEP_PRINT_FUNC:
248 	default:
249 		pr_err("Unsupported print arg type\n");
250 		/* we should warn... */
251 		return;
252 	}
253 
254 	if (args->next)
255 		define_event_symbols(event, ev_name, args->next);
256 }
257 
258 static SV *perl_process_callchain(struct perf_sample *sample,
259 				  struct perf_evsel *evsel,
260 				  struct addr_location *al)
261 {
262 	AV *list;
263 
264 	list = newAV();
265 	if (!list)
266 		goto exit;
267 
268 	if (!symbol_conf.use_callchain || !sample->callchain)
269 		goto exit;
270 
271 	if (thread__resolve_callchain(al->thread, &callchain_cursor, evsel,
272 				      sample, NULL, NULL, scripting_max_stack) != 0) {
273 		pr_err("Failed to resolve callchain. Skipping\n");
274 		goto exit;
275 	}
276 	callchain_cursor_commit(&callchain_cursor);
277 
278 
279 	while (1) {
280 		HV *elem;
281 		struct callchain_cursor_node *node;
282 		node = callchain_cursor_current(&callchain_cursor);
283 		if (!node)
284 			break;
285 
286 		elem = newHV();
287 		if (!elem)
288 			goto exit;
289 
290 		if (!hv_stores(elem, "ip", newSVuv(node->ip))) {
291 			hv_undef(elem);
292 			goto exit;
293 		}
294 
295 		if (node->sym) {
296 			HV *sym = newHV();
297 			if (!sym) {
298 				hv_undef(elem);
299 				goto exit;
300 			}
301 			if (!hv_stores(sym, "start",   newSVuv(node->sym->start)) ||
302 			    !hv_stores(sym, "end",     newSVuv(node->sym->end)) ||
303 			    !hv_stores(sym, "binding", newSVuv(node->sym->binding)) ||
304 			    !hv_stores(sym, "name",    newSVpvn(node->sym->name,
305 								node->sym->namelen)) ||
306 			    !hv_stores(elem, "sym",    newRV_noinc((SV*)sym))) {
307 				hv_undef(sym);
308 				hv_undef(elem);
309 				goto exit;
310 			}
311 		}
312 
313 		if (node->map) {
314 			struct map *map = node->map;
315 			const char *dsoname = "[unknown]";
316 			if (map && map->dso) {
317 				if (symbol_conf.show_kernel_path && map->dso->long_name)
318 					dsoname = map->dso->long_name;
319 				else
320 					dsoname = map->dso->name;
321 			}
322 			if (!hv_stores(elem, "dso", newSVpv(dsoname,0))) {
323 				hv_undef(elem);
324 				goto exit;
325 			}
326 		}
327 
328 		callchain_cursor_advance(&callchain_cursor);
329 		av_push(list, newRV_noinc((SV*)elem));
330 	}
331 
332 exit:
333 	return newRV_noinc((SV*)list);
334 }
335 
336 static void perl_process_tracepoint(struct perf_sample *sample,
337 				    struct perf_evsel *evsel,
338 				    struct addr_location *al)
339 {
340 	struct thread *thread = al->thread;
341 	struct tep_event_format *event = evsel->tp_format;
342 	struct tep_format_field *field;
343 	static char handler[256];
344 	unsigned long long val;
345 	unsigned long s, ns;
346 	int pid;
347 	int cpu = sample->cpu;
348 	void *data = sample->raw_data;
349 	unsigned long long nsecs = sample->time;
350 	const char *comm = thread__comm_str(thread);
351 
352 	dSP;
353 
354 	if (evsel->attr.type != PERF_TYPE_TRACEPOINT)
355 		return;
356 
357 	if (!event) {
358 		pr_debug("ug! no event found for type %" PRIu64, (u64)evsel->attr.config);
359 		return;
360 	}
361 
362 	pid = raw_field_value(event, "common_pid", data);
363 
364 	sprintf(handler, "%s::%s", event->system, event->name);
365 
366 	if (!test_and_set_bit(event->id, events_defined))
367 		define_event_symbols(event, handler, event->print_fmt.args);
368 
369 	s = nsecs / NSEC_PER_SEC;
370 	ns = nsecs - s * NSEC_PER_SEC;
371 
372 	scripting_context->event_data = data;
373 	scripting_context->pevent = evsel->tp_format->pevent;
374 
375 	ENTER;
376 	SAVETMPS;
377 	PUSHMARK(SP);
378 
379 	XPUSHs(sv_2mortal(newSVpv(handler, 0)));
380 	XPUSHs(sv_2mortal(newSViv(PTR2IV(scripting_context))));
381 	XPUSHs(sv_2mortal(newSVuv(cpu)));
382 	XPUSHs(sv_2mortal(newSVuv(s)));
383 	XPUSHs(sv_2mortal(newSVuv(ns)));
384 	XPUSHs(sv_2mortal(newSViv(pid)));
385 	XPUSHs(sv_2mortal(newSVpv(comm, 0)));
386 	XPUSHs(sv_2mortal(perl_process_callchain(sample, evsel, al)));
387 
388 	/* common fields other than pid can be accessed via xsub fns */
389 
390 	for (field = event->format.fields; field; field = field->next) {
391 		if (field->flags & TEP_FIELD_IS_STRING) {
392 			int offset;
393 			if (field->flags & TEP_FIELD_IS_DYNAMIC) {
394 				offset = *(int *)(data + field->offset);
395 				offset &= 0xffff;
396 			} else
397 				offset = field->offset;
398 			XPUSHs(sv_2mortal(newSVpv((char *)data + offset, 0)));
399 		} else { /* FIELD_IS_NUMERIC */
400 			val = read_size(event, data + field->offset,
401 					field->size);
402 			if (field->flags & TEP_FIELD_IS_SIGNED) {
403 				XPUSHs(sv_2mortal(newSViv(val)));
404 			} else {
405 				XPUSHs(sv_2mortal(newSVuv(val)));
406 			}
407 		}
408 	}
409 
410 	PUTBACK;
411 
412 	if (get_cv(handler, 0))
413 		call_pv(handler, G_SCALAR);
414 	else if (get_cv("main::trace_unhandled", 0)) {
415 		XPUSHs(sv_2mortal(newSVpv(handler, 0)));
416 		XPUSHs(sv_2mortal(newSViv(PTR2IV(scripting_context))));
417 		XPUSHs(sv_2mortal(newSVuv(cpu)));
418 		XPUSHs(sv_2mortal(newSVuv(nsecs)));
419 		XPUSHs(sv_2mortal(newSViv(pid)));
420 		XPUSHs(sv_2mortal(newSVpv(comm, 0)));
421 		XPUSHs(sv_2mortal(perl_process_callchain(sample, evsel, al)));
422 		call_pv("main::trace_unhandled", G_SCALAR);
423 	}
424 	SPAGAIN;
425 	PUTBACK;
426 	FREETMPS;
427 	LEAVE;
428 }
429 
430 static void perl_process_event_generic(union perf_event *event,
431 				       struct perf_sample *sample,
432 				       struct perf_evsel *evsel)
433 {
434 	dSP;
435 
436 	if (!get_cv("process_event", 0))
437 		return;
438 
439 	ENTER;
440 	SAVETMPS;
441 	PUSHMARK(SP);
442 	XPUSHs(sv_2mortal(newSVpvn((const char *)event, event->header.size)));
443 	XPUSHs(sv_2mortal(newSVpvn((const char *)&evsel->attr, sizeof(evsel->attr))));
444 	XPUSHs(sv_2mortal(newSVpvn((const char *)sample, sizeof(*sample))));
445 	XPUSHs(sv_2mortal(newSVpvn((const char *)sample->raw_data, sample->raw_size)));
446 	PUTBACK;
447 	call_pv("process_event", G_SCALAR);
448 	SPAGAIN;
449 	PUTBACK;
450 	FREETMPS;
451 	LEAVE;
452 }
453 
454 static void perl_process_event(union perf_event *event,
455 			       struct perf_sample *sample,
456 			       struct perf_evsel *evsel,
457 			       struct addr_location *al)
458 {
459 	perl_process_tracepoint(sample, evsel, al);
460 	perl_process_event_generic(event, sample, evsel);
461 }
462 
463 static void run_start_sub(void)
464 {
465 	dSP; /* access to Perl stack */
466 	PUSHMARK(SP);
467 
468 	if (get_cv("main::trace_begin", 0))
469 		call_pv("main::trace_begin", G_DISCARD | G_NOARGS);
470 }
471 
472 /*
473  * Start trace script
474  */
475 static int perl_start_script(const char *script, int argc, const char **argv)
476 {
477 	const char **command_line;
478 	int i, err = 0;
479 
480 	command_line = malloc((argc + 2) * sizeof(const char *));
481 	command_line[0] = "";
482 	command_line[1] = script;
483 	for (i = 2; i < argc + 2; i++)
484 		command_line[i] = argv[i - 2];
485 
486 	my_perl = perl_alloc();
487 	perl_construct(my_perl);
488 
489 	if (perl_parse(my_perl, xs_init, argc + 2, (char **)command_line,
490 		       (char **)NULL)) {
491 		err = -1;
492 		goto error;
493 	}
494 
495 	if (perl_run(my_perl)) {
496 		err = -1;
497 		goto error;
498 	}
499 
500 	if (SvTRUE(ERRSV)) {
501 		err = -1;
502 		goto error;
503 	}
504 
505 	run_start_sub();
506 
507 	free(command_line);
508 	return 0;
509 error:
510 	perl_free(my_perl);
511 	free(command_line);
512 
513 	return err;
514 }
515 
516 static int perl_flush_script(void)
517 {
518 	return 0;
519 }
520 
521 /*
522  * Stop trace script
523  */
524 static int perl_stop_script(void)
525 {
526 	dSP; /* access to Perl stack */
527 	PUSHMARK(SP);
528 
529 	if (get_cv("main::trace_end", 0))
530 		call_pv("main::trace_end", G_DISCARD | G_NOARGS);
531 
532 	perl_destruct(my_perl);
533 	perl_free(my_perl);
534 
535 	return 0;
536 }
537 
538 static int perl_generate_script(struct tep_handle *pevent, const char *outfile)
539 {
540 	struct tep_event_format *event = NULL;
541 	struct tep_format_field *f;
542 	char fname[PATH_MAX];
543 	int not_first, count;
544 	FILE *ofp;
545 
546 	sprintf(fname, "%s.pl", outfile);
547 	ofp = fopen(fname, "w");
548 	if (ofp == NULL) {
549 		fprintf(stderr, "couldn't open %s\n", fname);
550 		return -1;
551 	}
552 
553 	fprintf(ofp, "# perf script event handlers, "
554 		"generated by perf script -g perl\n");
555 
556 	fprintf(ofp, "# Licensed under the terms of the GNU GPL"
557 		" License version 2\n\n");
558 
559 	fprintf(ofp, "# The common_* event handler fields are the most useful "
560 		"fields common to\n");
561 
562 	fprintf(ofp, "# all events.  They don't necessarily correspond to "
563 		"the 'common_*' fields\n");
564 
565 	fprintf(ofp, "# in the format files.  Those fields not available as "
566 		"handler params can\n");
567 
568 	fprintf(ofp, "# be retrieved using Perl functions of the form "
569 		"common_*($context).\n");
570 
571 	fprintf(ofp, "# See Context.pm for the list of available "
572 		"functions.\n\n");
573 
574 	fprintf(ofp, "use lib \"$ENV{'PERF_EXEC_PATH'}/scripts/perl/"
575 		"Perf-Trace-Util/lib\";\n");
576 
577 	fprintf(ofp, "use lib \"./Perf-Trace-Util/lib\";\n");
578 	fprintf(ofp, "use Perf::Trace::Core;\n");
579 	fprintf(ofp, "use Perf::Trace::Context;\n");
580 	fprintf(ofp, "use Perf::Trace::Util;\n\n");
581 
582 	fprintf(ofp, "sub trace_begin\n{\n\t# optional\n}\n\n");
583 	fprintf(ofp, "sub trace_end\n{\n\t# optional\n}\n");
584 
585 
586 	fprintf(ofp, "\n\
587 sub print_backtrace\n\
588 {\n\
589 	my $callchain = shift;\n\
590 	for my $node (@$callchain)\n\
591 	{\n\
592 		if(exists $node->{sym})\n\
593 		{\n\
594 			printf( \"\\t[\\%%x] \\%%s\\n\", $node->{ip}, $node->{sym}{name});\n\
595 		}\n\
596 		else\n\
597 		{\n\
598 			printf( \"\\t[\\%%x]\\n\", $node{ip});\n\
599 		}\n\
600 	}\n\
601 }\n\n\
602 ");
603 
604 
605 	while ((event = trace_find_next_event(pevent, event))) {
606 		fprintf(ofp, "sub %s::%s\n{\n", event->system, event->name);
607 		fprintf(ofp, "\tmy (");
608 
609 		fprintf(ofp, "$event_name, ");
610 		fprintf(ofp, "$context, ");
611 		fprintf(ofp, "$common_cpu, ");
612 		fprintf(ofp, "$common_secs, ");
613 		fprintf(ofp, "$common_nsecs,\n");
614 		fprintf(ofp, "\t    $common_pid, ");
615 		fprintf(ofp, "$common_comm, ");
616 		fprintf(ofp, "$common_callchain,\n\t    ");
617 
618 		not_first = 0;
619 		count = 0;
620 
621 		for (f = event->format.fields; f; f = f->next) {
622 			if (not_first++)
623 				fprintf(ofp, ", ");
624 			if (++count % 5 == 0)
625 				fprintf(ofp, "\n\t    ");
626 
627 			fprintf(ofp, "$%s", f->name);
628 		}
629 		fprintf(ofp, ") = @_;\n\n");
630 
631 		fprintf(ofp, "\tprint_header($event_name, $common_cpu, "
632 			"$common_secs, $common_nsecs,\n\t             "
633 			"$common_pid, $common_comm, $common_callchain);\n\n");
634 
635 		fprintf(ofp, "\tprintf(\"");
636 
637 		not_first = 0;
638 		count = 0;
639 
640 		for (f = event->format.fields; f; f = f->next) {
641 			if (not_first++)
642 				fprintf(ofp, ", ");
643 			if (count && count % 4 == 0) {
644 				fprintf(ofp, "\".\n\t       \"");
645 			}
646 			count++;
647 
648 			fprintf(ofp, "%s=", f->name);
649 			if (f->flags & TEP_FIELD_IS_STRING ||
650 			    f->flags & TEP_FIELD_IS_FLAG ||
651 			    f->flags & TEP_FIELD_IS_SYMBOLIC)
652 				fprintf(ofp, "%%s");
653 			else if (f->flags & TEP_FIELD_IS_SIGNED)
654 				fprintf(ofp, "%%d");
655 			else
656 				fprintf(ofp, "%%u");
657 		}
658 
659 		fprintf(ofp, "\\n\",\n\t       ");
660 
661 		not_first = 0;
662 		count = 0;
663 
664 		for (f = event->format.fields; f; f = f->next) {
665 			if (not_first++)
666 				fprintf(ofp, ", ");
667 
668 			if (++count % 5 == 0)
669 				fprintf(ofp, "\n\t       ");
670 
671 			if (f->flags & TEP_FIELD_IS_FLAG) {
672 				if ((count - 1) % 5 != 0) {
673 					fprintf(ofp, "\n\t       ");
674 					count = 4;
675 				}
676 				fprintf(ofp, "flag_str(\"");
677 				fprintf(ofp, "%s::%s\", ", event->system,
678 					event->name);
679 				fprintf(ofp, "\"%s\", $%s)", f->name,
680 					f->name);
681 			} else if (f->flags & TEP_FIELD_IS_SYMBOLIC) {
682 				if ((count - 1) % 5 != 0) {
683 					fprintf(ofp, "\n\t       ");
684 					count = 4;
685 				}
686 				fprintf(ofp, "symbol_str(\"");
687 				fprintf(ofp, "%s::%s\", ", event->system,
688 					event->name);
689 				fprintf(ofp, "\"%s\", $%s)", f->name,
690 					f->name);
691 			} else
692 				fprintf(ofp, "$%s", f->name);
693 		}
694 
695 		fprintf(ofp, ");\n\n");
696 
697 		fprintf(ofp, "\tprint_backtrace($common_callchain);\n");
698 
699 		fprintf(ofp, "}\n\n");
700 	}
701 
702 	fprintf(ofp, "sub trace_unhandled\n{\n\tmy ($event_name, $context, "
703 		"$common_cpu, $common_secs, $common_nsecs,\n\t    "
704 		"$common_pid, $common_comm, $common_callchain) = @_;\n\n");
705 
706 	fprintf(ofp, "\tprint_header($event_name, $common_cpu, "
707 		"$common_secs, $common_nsecs,\n\t             $common_pid, "
708 		"$common_comm, $common_callchain);\n");
709 	fprintf(ofp, "\tprint_backtrace($common_callchain);\n");
710 	fprintf(ofp, "}\n\n");
711 
712 	fprintf(ofp, "sub print_header\n{\n"
713 		"\tmy ($event_name, $cpu, $secs, $nsecs, $pid, $comm) = @_;\n\n"
714 		"\tprintf(\"%%-20s %%5u %%05u.%%09u %%8u %%-20s \",\n\t       "
715 		"$event_name, $cpu, $secs, $nsecs, $pid, $comm);\n}\n");
716 
717 	fprintf(ofp,
718 		"\n# Packed byte string args of process_event():\n"
719 		"#\n"
720 		"# $event:\tunion perf_event\tutil/event.h\n"
721 		"# $attr:\tstruct perf_event_attr\tlinux/perf_event.h\n"
722 		"# $sample:\tstruct perf_sample\tutil/event.h\n"
723 		"# $raw_data:\tperf_sample->raw_data\tutil/event.h\n"
724 		"\n"
725 		"sub process_event\n"
726 		"{\n"
727 		"\tmy ($event, $attr, $sample, $raw_data) = @_;\n"
728 		"\n"
729 		"\tmy @event\t= unpack(\"LSS\", $event);\n"
730 		"\tmy @attr\t= unpack(\"LLQQQQQLLQQ\", $attr);\n"
731 		"\tmy @sample\t= unpack(\"QLLQQQQQLL\", $sample);\n"
732 		"\tmy @raw_data\t= unpack(\"C*\", $raw_data);\n"
733 		"\n"
734 		"\tuse Data::Dumper;\n"
735 		"\tprint Dumper \\@event, \\@attr, \\@sample, \\@raw_data;\n"
736 		"}\n");
737 
738 	fclose(ofp);
739 
740 	fprintf(stderr, "generated Perl script: %s\n", fname);
741 
742 	return 0;
743 }
744 
745 struct scripting_ops perl_scripting_ops = {
746 	.name = "Perl",
747 	.start_script = perl_start_script,
748 	.flush_script = perl_flush_script,
749 	.stop_script = perl_stop_script,
750 	.process_event = perl_process_event,
751 	.generate_script = perl_generate_script,
752 };
753