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 "../callchain.h"
38 #include "../dso.h"
39 #include "../machine.h"
40 #include "../map.h"
41 #include "../symbol.h"
42 #include "../thread.h"
43 #include "../event.h"
44 #include "../trace-event.h"
45 #include "../evsel.h"
46 #include "../debug.h"
47 
48 void boot_Perf__Trace__Context(pTHX_ CV *cv);
49 void boot_DynaLoader(pTHX_ CV *cv);
50 typedef PerlInterpreter * INTERP;
51 
52 void xs_init(pTHX);
53 
54 void xs_init(pTHX)
55 {
56 	const char *file = __FILE__;
57 	dXSUB_SYS;
58 
59 	newXS("Perf::Trace::Context::bootstrap", boot_Perf__Trace__Context,
60 	      file);
61 	newXS("DynaLoader::boot_DynaLoader", boot_DynaLoader, file);
62 }
63 
64 INTERP my_perl;
65 
66 #define TRACE_EVENT_TYPE_MAX				\
67 	((1 << (sizeof(unsigned short) * 8)) - 1)
68 
69 static DECLARE_BITMAP(events_defined, TRACE_EVENT_TYPE_MAX);
70 
71 extern struct scripting_context *scripting_context;
72 
73 static char *cur_field_name;
74 static int zero_flag_atom;
75 
76 static void define_symbolic_value(const char *ev_name,
77 				  const char *field_name,
78 				  const char *field_value,
79 				  const char *field_str)
80 {
81 	unsigned long long value;
82 	dSP;
83 
84 	value = eval_flag(field_value);
85 
86 	ENTER;
87 	SAVETMPS;
88 	PUSHMARK(SP);
89 
90 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
91 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
92 	XPUSHs(sv_2mortal(newSVuv(value)));
93 	XPUSHs(sv_2mortal(newSVpv(field_str, 0)));
94 
95 	PUTBACK;
96 	if (get_cv("main::define_symbolic_value", 0))
97 		call_pv("main::define_symbolic_value", G_SCALAR);
98 	SPAGAIN;
99 	PUTBACK;
100 	FREETMPS;
101 	LEAVE;
102 }
103 
104 static void define_symbolic_values(struct tep_print_flag_sym *field,
105 				   const char *ev_name,
106 				   const char *field_name)
107 {
108 	define_symbolic_value(ev_name, field_name, field->value, field->str);
109 	if (field->next)
110 		define_symbolic_values(field->next, ev_name, field_name);
111 }
112 
113 static void define_symbolic_field(const char *ev_name,
114 				  const char *field_name)
115 {
116 	dSP;
117 
118 	ENTER;
119 	SAVETMPS;
120 	PUSHMARK(SP);
121 
122 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
123 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
124 
125 	PUTBACK;
126 	if (get_cv("main::define_symbolic_field", 0))
127 		call_pv("main::define_symbolic_field", G_SCALAR);
128 	SPAGAIN;
129 	PUTBACK;
130 	FREETMPS;
131 	LEAVE;
132 }
133 
134 static void define_flag_value(const char *ev_name,
135 			      const char *field_name,
136 			      const char *field_value,
137 			      const char *field_str)
138 {
139 	unsigned long long value;
140 	dSP;
141 
142 	value = eval_flag(field_value);
143 
144 	ENTER;
145 	SAVETMPS;
146 	PUSHMARK(SP);
147 
148 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
149 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
150 	XPUSHs(sv_2mortal(newSVuv(value)));
151 	XPUSHs(sv_2mortal(newSVpv(field_str, 0)));
152 
153 	PUTBACK;
154 	if (get_cv("main::define_flag_value", 0))
155 		call_pv("main::define_flag_value", G_SCALAR);
156 	SPAGAIN;
157 	PUTBACK;
158 	FREETMPS;
159 	LEAVE;
160 }
161 
162 static void define_flag_values(struct tep_print_flag_sym *field,
163 			       const char *ev_name,
164 			       const char *field_name)
165 {
166 	define_flag_value(ev_name, field_name, field->value, field->str);
167 	if (field->next)
168 		define_flag_values(field->next, ev_name, field_name);
169 }
170 
171 static void define_flag_field(const char *ev_name,
172 			      const char *field_name,
173 			      const char *delim)
174 {
175 	dSP;
176 
177 	ENTER;
178 	SAVETMPS;
179 	PUSHMARK(SP);
180 
181 	XPUSHs(sv_2mortal(newSVpv(ev_name, 0)));
182 	XPUSHs(sv_2mortal(newSVpv(field_name, 0)));
183 	XPUSHs(sv_2mortal(newSVpv(delim, 0)));
184 
185 	PUTBACK;
186 	if (get_cv("main::define_flag_field", 0))
187 		call_pv("main::define_flag_field", G_SCALAR);
188 	SPAGAIN;
189 	PUTBACK;
190 	FREETMPS;
191 	LEAVE;
192 }
193 
194 static void define_event_symbols(struct tep_event *event,
195 				 const char *ev_name,
196 				 struct tep_print_arg *args)
197 {
198 	if (args == NULL)
199 		return;
200 
201 	switch (args->type) {
202 	case TEP_PRINT_NULL:
203 		break;
204 	case TEP_PRINT_ATOM:
205 		define_flag_value(ev_name, cur_field_name, "0",
206 				  args->atom.atom);
207 		zero_flag_atom = 0;
208 		break;
209 	case TEP_PRINT_FIELD:
210 		free(cur_field_name);
211 		cur_field_name = strdup(args->field.name);
212 		break;
213 	case TEP_PRINT_FLAGS:
214 		define_event_symbols(event, ev_name, args->flags.field);
215 		define_flag_field(ev_name, cur_field_name, args->flags.delim);
216 		define_flag_values(args->flags.flags, ev_name, cur_field_name);
217 		break;
218 	case TEP_PRINT_SYMBOL:
219 		define_event_symbols(event, ev_name, args->symbol.field);
220 		define_symbolic_field(ev_name, cur_field_name);
221 		define_symbolic_values(args->symbol.symbols, ev_name,
222 				       cur_field_name);
223 		break;
224 	case TEP_PRINT_HEX:
225 	case TEP_PRINT_HEX_STR:
226 		define_event_symbols(event, ev_name, args->hex.field);
227 		define_event_symbols(event, ev_name, args->hex.size);
228 		break;
229 	case TEP_PRINT_INT_ARRAY:
230 		define_event_symbols(event, ev_name, args->int_array.field);
231 		define_event_symbols(event, ev_name, args->int_array.count);
232 		define_event_symbols(event, ev_name, args->int_array.el_size);
233 		break;
234 	case TEP_PRINT_BSTRING:
235 	case TEP_PRINT_DYNAMIC_ARRAY:
236 	case TEP_PRINT_DYNAMIC_ARRAY_LEN:
237 	case TEP_PRINT_STRING:
238 	case TEP_PRINT_BITMASK:
239 		break;
240 	case TEP_PRINT_TYPE:
241 		define_event_symbols(event, ev_name, args->typecast.item);
242 		break;
243 	case TEP_PRINT_OP:
244 		if (strcmp(args->op.op, ":") == 0)
245 			zero_flag_atom = 1;
246 		define_event_symbols(event, ev_name, args->op.left);
247 		define_event_symbols(event, ev_name, args->op.right);
248 		break;
249 	case TEP_PRINT_FUNC:
250 	default:
251 		pr_err("Unsupported print arg type\n");
252 		/* we should warn... */
253 		return;
254 	}
255 
256 	if (args->next)
257 		define_event_symbols(event, ev_name, args->next);
258 }
259 
260 static SV *perl_process_callchain(struct perf_sample *sample,
261 				  struct evsel *evsel,
262 				  struct addr_location *al)
263 {
264 	AV *list;
265 
266 	list = newAV();
267 	if (!list)
268 		goto exit;
269 
270 	if (!symbol_conf.use_callchain || !sample->callchain)
271 		goto exit;
272 
273 	if (thread__resolve_callchain(al->thread, &callchain_cursor, evsel,
274 				      sample, NULL, NULL, scripting_max_stack) != 0) {
275 		pr_err("Failed to resolve callchain. Skipping\n");
276 		goto exit;
277 	}
278 	callchain_cursor_commit(&callchain_cursor);
279 
280 
281 	while (1) {
282 		HV *elem;
283 		struct callchain_cursor_node *node;
284 		node = callchain_cursor_current(&callchain_cursor);
285 		if (!node)
286 			break;
287 
288 		elem = newHV();
289 		if (!elem)
290 			goto exit;
291 
292 		if (!hv_stores(elem, "ip", newSVuv(node->ip))) {
293 			hv_undef(elem);
294 			goto exit;
295 		}
296 
297 		if (node->ms.sym) {
298 			HV *sym = newHV();
299 			if (!sym) {
300 				hv_undef(elem);
301 				goto exit;
302 			}
303 			if (!hv_stores(sym, "start",   newSVuv(node->ms.sym->start)) ||
304 			    !hv_stores(sym, "end",     newSVuv(node->ms.sym->end)) ||
305 			    !hv_stores(sym, "binding", newSVuv(node->ms.sym->binding)) ||
306 			    !hv_stores(sym, "name",    newSVpvn(node->ms.sym->name,
307 								node->ms.sym->namelen)) ||
308 			    !hv_stores(elem, "sym",    newRV_noinc((SV*)sym))) {
309 				hv_undef(sym);
310 				hv_undef(elem);
311 				goto exit;
312 			}
313 		}
314 
315 		if (node->ms.map) {
316 			struct map *map = node->ms.map;
317 			const char *dsoname = "[unknown]";
318 			if (map && map->dso) {
319 				if (symbol_conf.show_kernel_path && map->dso->long_name)
320 					dsoname = map->dso->long_name;
321 				else
322 					dsoname = map->dso->name;
323 			}
324 			if (!hv_stores(elem, "dso", newSVpv(dsoname,0))) {
325 				hv_undef(elem);
326 				goto exit;
327 			}
328 		}
329 
330 		callchain_cursor_advance(&callchain_cursor);
331 		av_push(list, newRV_noinc((SV*)elem));
332 	}
333 
334 exit:
335 	return newRV_noinc((SV*)list);
336 }
337 
338 static void perl_process_tracepoint(struct perf_sample *sample,
339 				    struct evsel *evsel,
340 				    struct addr_location *al)
341 {
342 	struct thread *thread = al->thread;
343 	struct tep_event *event = evsel->tp_format;
344 	struct tep_format_field *field;
345 	static char handler[256];
346 	unsigned long long val;
347 	unsigned long s, ns;
348 	int pid;
349 	int cpu = sample->cpu;
350 	void *data = sample->raw_data;
351 	unsigned long long nsecs = sample->time;
352 	const char *comm = thread__comm_str(thread);
353 
354 	dSP;
355 
356 	if (evsel->core.attr.type != PERF_TYPE_TRACEPOINT)
357 		return;
358 
359 	if (!event) {
360 		pr_debug("ug! no event found for type %" PRIu64, (u64)evsel->core.attr.config);
361 		return;
362 	}
363 
364 	pid = raw_field_value(event, "common_pid", data);
365 
366 	sprintf(handler, "%s::%s", event->system, event->name);
367 
368 	if (!test_and_set_bit(event->id, events_defined))
369 		define_event_symbols(event, handler, event->print_fmt.args);
370 
371 	s = nsecs / NSEC_PER_SEC;
372 	ns = nsecs - s * NSEC_PER_SEC;
373 
374 	ENTER;
375 	SAVETMPS;
376 	PUSHMARK(SP);
377 
378 	XPUSHs(sv_2mortal(newSVpv(handler, 0)));
379 	XPUSHs(sv_2mortal(newSViv(PTR2IV(scripting_context))));
380 	XPUSHs(sv_2mortal(newSVuv(cpu)));
381 	XPUSHs(sv_2mortal(newSVuv(s)));
382 	XPUSHs(sv_2mortal(newSVuv(ns)));
383 	XPUSHs(sv_2mortal(newSViv(pid)));
384 	XPUSHs(sv_2mortal(newSVpv(comm, 0)));
385 	XPUSHs(sv_2mortal(perl_process_callchain(sample, evsel, al)));
386 
387 	/* common fields other than pid can be accessed via xsub fns */
388 
389 	for (field = event->format.fields; field; field = field->next) {
390 		if (field->flags & TEP_FIELD_IS_STRING) {
391 			int offset;
392 			if (field->flags & TEP_FIELD_IS_DYNAMIC) {
393 				offset = *(int *)(data + field->offset);
394 				offset &= 0xffff;
395 				if (field->flags & TEP_FIELD_IS_RELATIVE)
396 					offset += field->offset + field->size;
397 			} else
398 				offset = field->offset;
399 			XPUSHs(sv_2mortal(newSVpv((char *)data + offset, 0)));
400 		} else { /* FIELD_IS_NUMERIC */
401 			val = read_size(event, data + field->offset,
402 					field->size);
403 			if (field->flags & TEP_FIELD_IS_SIGNED) {
404 				XPUSHs(sv_2mortal(newSViv(val)));
405 			} else {
406 				XPUSHs(sv_2mortal(newSVuv(val)));
407 			}
408 		}
409 	}
410 
411 	PUTBACK;
412 
413 	if (get_cv(handler, 0))
414 		call_pv(handler, G_SCALAR);
415 	else if (get_cv("main::trace_unhandled", 0)) {
416 		XPUSHs(sv_2mortal(newSVpv(handler, 0)));
417 		XPUSHs(sv_2mortal(newSViv(PTR2IV(scripting_context))));
418 		XPUSHs(sv_2mortal(newSVuv(cpu)));
419 		XPUSHs(sv_2mortal(newSVuv(nsecs)));
420 		XPUSHs(sv_2mortal(newSViv(pid)));
421 		XPUSHs(sv_2mortal(newSVpv(comm, 0)));
422 		XPUSHs(sv_2mortal(perl_process_callchain(sample, evsel, al)));
423 		call_pv("main::trace_unhandled", G_SCALAR);
424 	}
425 	SPAGAIN;
426 	PUTBACK;
427 	FREETMPS;
428 	LEAVE;
429 }
430 
431 static void perl_process_event_generic(union perf_event *event,
432 				       struct perf_sample *sample,
433 				       struct evsel *evsel)
434 {
435 	dSP;
436 
437 	if (!get_cv("process_event", 0))
438 		return;
439 
440 	ENTER;
441 	SAVETMPS;
442 	PUSHMARK(SP);
443 	XPUSHs(sv_2mortal(newSVpvn((const char *)event, event->header.size)));
444 	XPUSHs(sv_2mortal(newSVpvn((const char *)&evsel->core.attr, sizeof(evsel->core.attr))));
445 	XPUSHs(sv_2mortal(newSVpvn((const char *)sample, sizeof(*sample))));
446 	XPUSHs(sv_2mortal(newSVpvn((const char *)sample->raw_data, sample->raw_size)));
447 	PUTBACK;
448 	call_pv("process_event", G_SCALAR);
449 	SPAGAIN;
450 	PUTBACK;
451 	FREETMPS;
452 	LEAVE;
453 }
454 
455 static void perl_process_event(union perf_event *event,
456 			       struct perf_sample *sample,
457 			       struct evsel *evsel,
458 			       struct addr_location *al,
459 			       struct addr_location *addr_al)
460 {
461 	scripting_context__update(scripting_context, event, sample, evsel, al, addr_al);
462 	perl_process_tracepoint(sample, evsel, al);
463 	perl_process_event_generic(event, sample, evsel);
464 }
465 
466 static void run_start_sub(void)
467 {
468 	dSP; /* access to Perl stack */
469 	PUSHMARK(SP);
470 
471 	if (get_cv("main::trace_begin", 0))
472 		call_pv("main::trace_begin", G_DISCARD | G_NOARGS);
473 }
474 
475 /*
476  * Start trace script
477  */
478 static int perl_start_script(const char *script, int argc, const char **argv,
479 			     struct perf_session *session)
480 {
481 	const char **command_line;
482 	int i, err = 0;
483 
484 	scripting_context->session = session;
485 
486 	command_line = malloc((argc + 2) * sizeof(const char *));
487 	command_line[0] = "";
488 	command_line[1] = script;
489 	for (i = 2; i < argc + 2; i++)
490 		command_line[i] = argv[i - 2];
491 
492 	my_perl = perl_alloc();
493 	perl_construct(my_perl);
494 
495 	if (perl_parse(my_perl, xs_init, argc + 2, (char **)command_line,
496 		       (char **)NULL)) {
497 		err = -1;
498 		goto error;
499 	}
500 
501 	if (perl_run(my_perl)) {
502 		err = -1;
503 		goto error;
504 	}
505 
506 	if (SvTRUE(ERRSV)) {
507 		err = -1;
508 		goto error;
509 	}
510 
511 	run_start_sub();
512 
513 	free(command_line);
514 	return 0;
515 error:
516 	perl_free(my_perl);
517 	free(command_line);
518 
519 	return err;
520 }
521 
522 static int perl_flush_script(void)
523 {
524 	return 0;
525 }
526 
527 /*
528  * Stop trace script
529  */
530 static int perl_stop_script(void)
531 {
532 	dSP; /* access to Perl stack */
533 	PUSHMARK(SP);
534 
535 	if (get_cv("main::trace_end", 0))
536 		call_pv("main::trace_end", G_DISCARD | G_NOARGS);
537 
538 	perl_destruct(my_perl);
539 	perl_free(my_perl);
540 
541 	return 0;
542 }
543 
544 static int perl_generate_script(struct tep_handle *pevent, const char *outfile)
545 {
546 	int i, not_first, count, nr_events;
547 	struct tep_event **all_events;
548 	struct tep_event *event = NULL;
549 	struct tep_format_field *f;
550 	char fname[PATH_MAX];
551 	FILE *ofp;
552 
553 	sprintf(fname, "%s.pl", outfile);
554 	ofp = fopen(fname, "w");
555 	if (ofp == NULL) {
556 		fprintf(stderr, "couldn't open %s\n", fname);
557 		return -1;
558 	}
559 
560 	fprintf(ofp, "# perf script event handlers, "
561 		"generated by perf script -g perl\n");
562 
563 	fprintf(ofp, "# Licensed under the terms of the GNU GPL"
564 		" License version 2\n\n");
565 
566 	fprintf(ofp, "# The common_* event handler fields are the most useful "
567 		"fields common to\n");
568 
569 	fprintf(ofp, "# all events.  They don't necessarily correspond to "
570 		"the 'common_*' fields\n");
571 
572 	fprintf(ofp, "# in the format files.  Those fields not available as "
573 		"handler params can\n");
574 
575 	fprintf(ofp, "# be retrieved using Perl functions of the form "
576 		"common_*($context).\n");
577 
578 	fprintf(ofp, "# See Context.pm for the list of available "
579 		"functions.\n\n");
580 
581 	fprintf(ofp, "use lib \"$ENV{'PERF_EXEC_PATH'}/scripts/perl/"
582 		"Perf-Trace-Util/lib\";\n");
583 
584 	fprintf(ofp, "use lib \"./Perf-Trace-Util/lib\";\n");
585 	fprintf(ofp, "use Perf::Trace::Core;\n");
586 	fprintf(ofp, "use Perf::Trace::Context;\n");
587 	fprintf(ofp, "use Perf::Trace::Util;\n\n");
588 
589 	fprintf(ofp, "sub trace_begin\n{\n\t# optional\n}\n\n");
590 	fprintf(ofp, "sub trace_end\n{\n\t# optional\n}\n");
591 
592 
593 	fprintf(ofp, "\n\
594 sub print_backtrace\n\
595 {\n\
596 	my $callchain = shift;\n\
597 	for my $node (@$callchain)\n\
598 	{\n\
599 		if(exists $node->{sym})\n\
600 		{\n\
601 			printf( \"\\t[\\%%x] \\%%s\\n\", $node->{ip}, $node->{sym}{name});\n\
602 		}\n\
603 		else\n\
604 		{\n\
605 			printf( \"\\t[\\%%x]\\n\", $node{ip});\n\
606 		}\n\
607 	}\n\
608 }\n\n\
609 ");
610 
611 	nr_events = tep_get_events_count(pevent);
612 	all_events = tep_list_events(pevent, TEP_EVENT_SORT_ID);
613 
614 	for (i = 0; all_events && i < nr_events; i++) {
615 		event = all_events[i];
616 		fprintf(ofp, "sub %s::%s\n{\n", event->system, event->name);
617 		fprintf(ofp, "\tmy (");
618 
619 		fprintf(ofp, "$event_name, ");
620 		fprintf(ofp, "$context, ");
621 		fprintf(ofp, "$common_cpu, ");
622 		fprintf(ofp, "$common_secs, ");
623 		fprintf(ofp, "$common_nsecs,\n");
624 		fprintf(ofp, "\t    $common_pid, ");
625 		fprintf(ofp, "$common_comm, ");
626 		fprintf(ofp, "$common_callchain,\n\t    ");
627 
628 		not_first = 0;
629 		count = 0;
630 
631 		for (f = event->format.fields; f; f = f->next) {
632 			if (not_first++)
633 				fprintf(ofp, ", ");
634 			if (++count % 5 == 0)
635 				fprintf(ofp, "\n\t    ");
636 
637 			fprintf(ofp, "$%s", f->name);
638 		}
639 		fprintf(ofp, ") = @_;\n\n");
640 
641 		fprintf(ofp, "\tprint_header($event_name, $common_cpu, "
642 			"$common_secs, $common_nsecs,\n\t             "
643 			"$common_pid, $common_comm, $common_callchain);\n\n");
644 
645 		fprintf(ofp, "\tprintf(\"");
646 
647 		not_first = 0;
648 		count = 0;
649 
650 		for (f = event->format.fields; f; f = f->next) {
651 			if (not_first++)
652 				fprintf(ofp, ", ");
653 			if (count && count % 4 == 0) {
654 				fprintf(ofp, "\".\n\t       \"");
655 			}
656 			count++;
657 
658 			fprintf(ofp, "%s=", f->name);
659 			if (f->flags & TEP_FIELD_IS_STRING ||
660 			    f->flags & TEP_FIELD_IS_FLAG ||
661 			    f->flags & TEP_FIELD_IS_SYMBOLIC)
662 				fprintf(ofp, "%%s");
663 			else if (f->flags & TEP_FIELD_IS_SIGNED)
664 				fprintf(ofp, "%%d");
665 			else
666 				fprintf(ofp, "%%u");
667 		}
668 
669 		fprintf(ofp, "\\n\",\n\t       ");
670 
671 		not_first = 0;
672 		count = 0;
673 
674 		for (f = event->format.fields; f; f = f->next) {
675 			if (not_first++)
676 				fprintf(ofp, ", ");
677 
678 			if (++count % 5 == 0)
679 				fprintf(ofp, "\n\t       ");
680 
681 			if (f->flags & TEP_FIELD_IS_FLAG) {
682 				if ((count - 1) % 5 != 0) {
683 					fprintf(ofp, "\n\t       ");
684 					count = 4;
685 				}
686 				fprintf(ofp, "flag_str(\"");
687 				fprintf(ofp, "%s::%s\", ", event->system,
688 					event->name);
689 				fprintf(ofp, "\"%s\", $%s)", f->name,
690 					f->name);
691 			} else if (f->flags & TEP_FIELD_IS_SYMBOLIC) {
692 				if ((count - 1) % 5 != 0) {
693 					fprintf(ofp, "\n\t       ");
694 					count = 4;
695 				}
696 				fprintf(ofp, "symbol_str(\"");
697 				fprintf(ofp, "%s::%s\", ", event->system,
698 					event->name);
699 				fprintf(ofp, "\"%s\", $%s)", f->name,
700 					f->name);
701 			} else
702 				fprintf(ofp, "$%s", f->name);
703 		}
704 
705 		fprintf(ofp, ");\n\n");
706 
707 		fprintf(ofp, "\tprint_backtrace($common_callchain);\n");
708 
709 		fprintf(ofp, "}\n\n");
710 	}
711 
712 	fprintf(ofp, "sub trace_unhandled\n{\n\tmy ($event_name, $context, "
713 		"$common_cpu, $common_secs, $common_nsecs,\n\t    "
714 		"$common_pid, $common_comm, $common_callchain) = @_;\n\n");
715 
716 	fprintf(ofp, "\tprint_header($event_name, $common_cpu, "
717 		"$common_secs, $common_nsecs,\n\t             $common_pid, "
718 		"$common_comm, $common_callchain);\n");
719 	fprintf(ofp, "\tprint_backtrace($common_callchain);\n");
720 	fprintf(ofp, "}\n\n");
721 
722 	fprintf(ofp, "sub print_header\n{\n"
723 		"\tmy ($event_name, $cpu, $secs, $nsecs, $pid, $comm) = @_;\n\n"
724 		"\tprintf(\"%%-20s %%5u %%05u.%%09u %%8u %%-20s \",\n\t       "
725 		"$event_name, $cpu, $secs, $nsecs, $pid, $comm);\n}\n");
726 
727 	fprintf(ofp,
728 		"\n# Packed byte string args of process_event():\n"
729 		"#\n"
730 		"# $event:\tunion perf_event\tutil/event.h\n"
731 		"# $attr:\tstruct perf_event_attr\tlinux/perf_event.h\n"
732 		"# $sample:\tstruct perf_sample\tutil/event.h\n"
733 		"# $raw_data:\tperf_sample->raw_data\tutil/event.h\n"
734 		"\n"
735 		"sub process_event\n"
736 		"{\n"
737 		"\tmy ($event, $attr, $sample, $raw_data) = @_;\n"
738 		"\n"
739 		"\tmy @event\t= unpack(\"LSS\", $event);\n"
740 		"\tmy @attr\t= unpack(\"LLQQQQQLLQQ\", $attr);\n"
741 		"\tmy @sample\t= unpack(\"QLLQQQQQLL\", $sample);\n"
742 		"\tmy @raw_data\t= unpack(\"C*\", $raw_data);\n"
743 		"\n"
744 		"\tuse Data::Dumper;\n"
745 		"\tprint Dumper \\@event, \\@attr, \\@sample, \\@raw_data;\n"
746 		"}\n");
747 
748 	fclose(ofp);
749 
750 	fprintf(stderr, "generated Perl script: %s\n", fname);
751 
752 	return 0;
753 }
754 
755 struct scripting_ops perl_scripting_ops = {
756 	.name = "Perl",
757 	.dirname = "perl",
758 	.start_script = perl_start_script,
759 	.flush_script = perl_flush_script,
760 	.stop_script = perl_stop_script,
761 	.process_event = perl_process_event,
762 	.generate_script = perl_generate_script,
763 };
764