xref: /linux/tools/perf/tests/code-reading.c (revision 9e906a9dead17d81d6c2687f65e159231d0e3286)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <linux/kconfig.h>
4 #include <linux/kernel.h>
5 #include <linux/rbtree.h>
6 #include <linux/types.h>
7 #include <inttypes.h>
8 #include <stdlib.h>
9 #include <unistd.h>
10 #include <stdio.h>
11 #include <string.h>
12 #include <sys/param.h>
13 #include <sys/utsname.h>
14 #include <perf/cpumap.h>
15 #include <perf/evlist.h>
16 #include <perf/mmap.h>
17 
18 #include "debug.h"
19 #include "dso.h"
20 #include "env.h"
21 #include "parse-events.h"
22 #include "evlist.h"
23 #include "evsel.h"
24 #include "thread_map.h"
25 #include "machine.h"
26 #include "map.h"
27 #include "symbol.h"
28 #include "event.h"
29 #include "record.h"
30 #include "util/mmap.h"
31 #include "util/string2.h"
32 #include "util/synthetic-events.h"
33 #include "util/util.h"
34 #include "thread.h"
35 
36 #include "tests.h"
37 
38 #include <linux/ctype.h>
39 
40 #define BUFSZ	1024
41 #define READLEN	128
42 
43 struct tested_section {
44 	struct rb_node rb_node;
45 	u64 addr;
46 	char *path;
47 };
48 
tested_code_insert_or_exists(const char * path,u64 addr,struct rb_root * tested_sections)49 static bool tested_code_insert_or_exists(const char *path, u64 addr,
50 					 struct rb_root *tested_sections)
51 {
52 	struct rb_node **node = &tested_sections->rb_node;
53 	struct rb_node *parent = NULL;
54 	struct tested_section *data;
55 
56 	while (*node) {
57 		int cmp;
58 
59 		parent = *node;
60 		data = rb_entry(*node, struct tested_section, rb_node);
61 		cmp = strcmp(path, data->path);
62 		if (!cmp) {
63 			if (addr < data->addr)
64 				cmp = -1;
65 			else if (addr > data->addr)
66 				cmp = 1;
67 			else
68 				return true; /* already tested */
69 		}
70 
71 		if (cmp < 0)
72 			node = &(*node)->rb_left;
73 		else
74 			node = &(*node)->rb_right;
75 	}
76 
77 	data = zalloc(sizeof(*data));
78 	if (!data)
79 		return true;
80 
81 	data->addr = addr;
82 	data->path = strdup(path);
83 	if (!data->path) {
84 		free(data);
85 		return true;
86 	}
87 	rb_link_node(&data->rb_node, parent, node);
88 	rb_insert_color(&data->rb_node, tested_sections);
89 	return false;
90 }
91 
tested_sections__free(struct rb_root * root)92 static void tested_sections__free(struct rb_root *root)
93 {
94 	while (!RB_EMPTY_ROOT(root)) {
95 		struct rb_node *node = rb_first(root);
96 		struct tested_section *ts = rb_entry(node,
97 						     struct tested_section,
98 						     rb_node);
99 
100 		rb_erase(node, root);
101 		free(ts->path);
102 		free(ts);
103 	}
104 }
105 
read_objdump_chunk(const char ** line,unsigned char ** buf,size_t * buf_len)106 static size_t read_objdump_chunk(const char **line, unsigned char **buf,
107 				 size_t *buf_len)
108 {
109 	size_t bytes_read = 0;
110 	unsigned char *chunk_start = *buf;
111 
112 	/* Read bytes */
113 	while (*buf_len > 0) {
114 		char c1, c2;
115 
116 		/* Get 2 hex digits */
117 		c1 = *(*line)++;
118 		if (!isxdigit(c1))
119 			break;
120 		c2 = *(*line)++;
121 		if (!isxdigit(c2))
122 			break;
123 
124 		/* Store byte and advance buf */
125 		**buf = (hex(c1) << 4) | hex(c2);
126 		(*buf)++;
127 		(*buf_len)--;
128 		bytes_read++;
129 
130 		/* End of chunk? */
131 		if (isspace(**line))
132 			break;
133 	}
134 
135 	/*
136 	 * objdump will display raw insn as LE if code endian
137 	 * is LE and bytes_per_chunk > 1. In that case reverse
138 	 * the chunk we just read.
139 	 *
140 	 * see disassemble_bytes() at binutils/objdump.c for details
141 	 * how objdump chooses display endian)
142 	 */
143 	if (bytes_read > 1 && !host_is_bigendian()) {
144 		unsigned char *chunk_end = chunk_start + bytes_read - 1;
145 		unsigned char tmp;
146 
147 		while (chunk_start < chunk_end) {
148 			tmp = *chunk_start;
149 			*chunk_start = *chunk_end;
150 			*chunk_end = tmp;
151 			chunk_start++;
152 			chunk_end--;
153 		}
154 	}
155 
156 	return bytes_read;
157 }
158 
read_objdump_line(const char * line,unsigned char * buf,size_t buf_len)159 static size_t read_objdump_line(const char *line, unsigned char *buf,
160 				size_t buf_len)
161 {
162 	const char *p;
163 	size_t ret, bytes_read = 0;
164 
165 	/* Skip to a colon */
166 	p = strchr(line, ':');
167 	if (!p)
168 		return 0;
169 	p++;
170 
171 	/* Skip initial spaces */
172 	while (*p) {
173 		if (!isspace(*p))
174 			break;
175 		p++;
176 	}
177 
178 	do {
179 		ret = read_objdump_chunk(&p, &buf, &buf_len);
180 		bytes_read += ret;
181 		p++;
182 	} while (ret > 0);
183 
184 	/* return number of successfully read bytes */
185 	return bytes_read;
186 }
187 
read_objdump_output(FILE * f,void * buf,size_t * len,u64 start_addr)188 static int read_objdump_output(FILE *f, void *buf, size_t *len, u64 start_addr)
189 {
190 	char *line = NULL;
191 	size_t line_len, off_last = 0;
192 	ssize_t ret;
193 	int err = 0;
194 	u64 addr, last_addr = start_addr;
195 
196 	while (off_last < *len) {
197 		size_t off, read_bytes, written_bytes;
198 		unsigned char tmp[BUFSZ];
199 
200 		ret = getline(&line, &line_len, f);
201 		if (feof(f))
202 			break;
203 		if (ret < 0) {
204 			pr_debug("getline failed\n");
205 			err = -1;
206 			break;
207 		}
208 
209 		/* read objdump data into temporary buffer */
210 		read_bytes = read_objdump_line(line, tmp, sizeof(tmp));
211 		if (!read_bytes)
212 			continue;
213 
214 		if (sscanf(line, "%"PRIx64, &addr) != 1)
215 			continue;
216 		if (addr < last_addr) {
217 			pr_debug("addr going backwards, read beyond section?\n");
218 			break;
219 		}
220 		last_addr = addr;
221 
222 		/* copy it from temporary buffer to 'buf' according
223 		 * to address on current objdump line */
224 		off = addr - start_addr;
225 		if (off >= *len)
226 			break;
227 		written_bytes = MIN(read_bytes, *len - off);
228 		memcpy(buf + off, tmp, written_bytes);
229 		off_last = off + written_bytes;
230 	}
231 
232 	/* len returns number of bytes that could not be read */
233 	*len -= off_last;
234 
235 	free(line);
236 
237 	return err;
238 }
239 
240 /*
241  * Only gets GNU objdump version. Returns 0 for llvm-objdump.
242  */
objdump_version(void)243 static int objdump_version(void)
244 {
245 	size_t line_len;
246 	char cmd[PATH_MAX * 2];
247 	char *line = NULL;
248 	const char *fmt;
249 	FILE *f;
250 	int ret;
251 
252 	int version_tmp, version_num = 0;
253 	char *version = 0, *token;
254 
255 	fmt = "%s --version";
256 	ret = snprintf(cmd, sizeof(cmd), fmt, test_objdump_path);
257 	if (ret <= 0 || (size_t)ret >= sizeof(cmd))
258 		return -1;
259 	/* Ignore objdump errors */
260 	strcat(cmd, " 2>/dev/null");
261 	f = popen(cmd, "r");
262 	if (!f) {
263 		pr_debug("popen failed\n");
264 		return -1;
265 	}
266 	/* Get first line of objdump --version output */
267 	ret = getline(&line, &line_len, f);
268 	pclose(f);
269 	if (ret < 0) {
270 		pr_debug("getline failed\n");
271 		return -1;
272 	}
273 
274 	token = strsep(&line, " ");
275 	if (token != NULL && !strcmp(token, "GNU")) {
276 		// version is last part of first line of objdump --version output.
277 		while ((token = strsep(&line, " ")))
278 			version = token;
279 
280 		// Convert version into a format we can compare with
281 		token = strsep(&version, ".");
282 		version_num = atoi(token);
283 		if (version_num)
284 			version_num *= 10000;
285 
286 		token = strsep(&version, ".");
287 		version_tmp = atoi(token);
288 		if (token)
289 			version_num += version_tmp * 100;
290 
291 		token = strsep(&version, ".");
292 		version_tmp = atoi(token);
293 		if (token)
294 			version_num += version_tmp;
295 	}
296 
297 	return version_num;
298 }
299 
read_via_objdump(const char * filename,u64 addr,void * buf,size_t len)300 static int read_via_objdump(const char *filename, u64 addr, void *buf,
301 			    size_t len)
302 {
303 	u64 stop_address = addr + len;
304 	struct utsname uname_buf;
305 	char cmd[PATH_MAX * 2];
306 	const char *fmt;
307 	FILE *f;
308 	int ret;
309 
310 	ret = uname(&uname_buf);
311 	if (ret) {
312 		pr_debug("uname failed\n");
313 		return -1;
314 	}
315 
316 	if (!strncmp(uname_buf.machine, "riscv", 5)) {
317 		int version = objdump_version();
318 
319 		/* Default to this workaround if version parsing fails */
320 		if (version < 0 || version > 24100) {
321 			/*
322 			 * Starting at riscv objdump version 2.41, dumping in
323 			 * the middle of an instruction is not supported. riscv
324 			 * instructions are aligned along 2-byte intervals and
325 			 * can be either 2-bytes or 4-bytes. This makes it
326 			 * possible that the stop-address lands in the middle of
327 			 * a 4-byte instruction. Increase the stop_address by
328 			 * two to ensure an instruction is not cut in half, but
329 			 * leave the len as-is so only the expected number of
330 			 * bytes are collected.
331 			 */
332 			stop_address += 2;
333 		}
334 	}
335 
336 	fmt = "%s -z -d --start-address=0x%"PRIx64" --stop-address=0x%"PRIx64" %s";
337 	ret = snprintf(cmd, sizeof(cmd), fmt, test_objdump_path, addr, stop_address,
338 		       filename);
339 	if (ret <= 0 || (size_t)ret >= sizeof(cmd))
340 		return -1;
341 
342 	pr_debug("Objdump command is: %s\n", cmd);
343 
344 	/* Ignore objdump errors */
345 	strcat(cmd, " 2>/dev/null");
346 
347 	f = popen(cmd, "r");
348 	if (!f) {
349 		pr_debug("popen failed\n");
350 		return -1;
351 	}
352 
353 	ret = read_objdump_output(f, buf, &len, addr);
354 	if (len) {
355 		pr_debug("objdump read too few bytes: %zd\n", len);
356 		if (!ret)
357 			ret = len;
358 	}
359 
360 	pclose(f);
361 
362 	return ret;
363 }
364 
dump_buf(unsigned char * buf,size_t len)365 static void dump_buf(unsigned char *buf, size_t len)
366 {
367 	size_t i;
368 
369 	for (i = 0; i < len; i++) {
370 		pr_debug("0x%02x ", buf[i]);
371 		if (i % 16 == 15)
372 			pr_debug("\n");
373 	}
374 	pr_debug("\n");
375 }
376 
read_object_code(u64 addr,size_t len,u8 cpumode,struct thread * thread,struct rb_root * tested_sections)377 static int read_object_code(u64 addr, size_t len, u8 cpumode,
378 			    struct thread *thread,
379 			    struct rb_root *tested_sections)
380 {
381 	struct addr_location al;
382 	unsigned char buf1[BUFSZ] = {0};
383 	unsigned char buf2[BUFSZ] = {0};
384 	size_t ret_len;
385 	u64 objdump_addr;
386 	u64 skip_addr;
387 	const char *objdump_name;
388 	char decomp_name[KMOD_DECOMP_LEN];
389 	bool decomp = false;
390 	int ret, err = 0;
391 	struct dso *dso;
392 
393 	pr_debug("Reading object code for memory address: %#"PRIx64"\n", addr);
394 
395 	addr_location__init(&al);
396 	if (!thread__find_map(thread, cpumode, addr, &al) || !map__dso(al.map)) {
397 		if (cpumode == PERF_RECORD_MISC_HYPERVISOR) {
398 			pr_debug("Hypervisor address can not be resolved - skipping\n");
399 			goto out;
400 		}
401 
402 		pr_debug("thread__find_map failed\n");
403 		err = -1;
404 		goto out;
405 	}
406 	dso = map__dso(al.map);
407 	pr_debug("File is: %s\n", dso__long_name(dso));
408 
409 	if (dso__symtab_type(dso) == DSO_BINARY_TYPE__KALLSYMS && !dso__is_kcore(dso)) {
410 		pr_debug("Unexpected kernel address - skipping\n");
411 		goto out;
412 	}
413 
414 	/*
415 	 * Don't retest the same addresses. objdump struggles with kcore - try
416 	 * each map only once even if the address is different.
417 	 */
418 	skip_addr = dso__is_kcore(dso) ? map__start(al.map) : al.addr;
419 	if (tested_code_insert_or_exists(dso__long_name(dso), skip_addr,
420 					 tested_sections)) {
421 		pr_debug("Already tested %s @ %#"PRIx64" - skipping\n",
422 			 dso__long_name(dso), skip_addr);
423 		goto out;
424 	}
425 
426 	pr_debug("On file address is: %#"PRIx64"\n", al.addr);
427 
428 	if (len > BUFSZ)
429 		len = BUFSZ;
430 
431 	/* Do not go off the map */
432 	if (addr + len > map__end(al.map))
433 		len = map__end(al.map) - addr;
434 
435 	/*
436 	 * Some architectures (ex: powerpc) have stubs (trampolines) in kernel
437 	 * modules to manage long jumps. Check if the ip offset falls in stubs
438 	 * sections for kernel modules. And skip module address after text end
439 	 */
440 	if (dso__is_kmod(dso) && al.addr > dso__text_end(dso)) {
441 		pr_debug("skipping the module address %#"PRIx64" after text end\n", al.addr);
442 		goto out;
443 	}
444 
445 	/* Read the object code using perf */
446 	ret_len = dso__data_read_offset(dso, maps__machine(thread__maps(thread)),
447 					al.addr, buf1, len);
448 	if (ret_len != len) {
449 		pr_debug("dso__data_read_offset failed\n");
450 		err = -1;
451 		goto out;
452 	}
453 
454 	/*
455 	 * Converting addresses for use by objdump requires more information.
456 	 * map__load() does that.  See map__rip_2objdump() for details.
457 	 */
458 	if (map__load(al.map)) {
459 		err = -1;
460 		goto out;
461 	}
462 
463 	objdump_name = dso__long_name(dso);
464 	if (dso__needs_decompress(dso)) {
465 		if (dso__decompress_kmodule_path(dso, objdump_name,
466 						 decomp_name,
467 						 sizeof(decomp_name)) < 0) {
468 			pr_debug("decompression failed\n");
469 			err = -1;
470 			goto out;
471 		}
472 
473 		decomp = true;
474 		objdump_name = decomp_name;
475 	}
476 
477 	/* Read the object code using objdump */
478 	objdump_addr = map__rip_2objdump(al.map, al.addr);
479 	ret = read_via_objdump(objdump_name, objdump_addr, buf2, len);
480 
481 	if (decomp)
482 		unlink(objdump_name);
483 
484 	if (ret > 0) {
485 		/*
486 		 * The kernel maps are inaccurate - assume objdump is right in
487 		 * that case.
488 		 */
489 		if (cpumode == PERF_RECORD_MISC_KERNEL ||
490 		    cpumode == PERF_RECORD_MISC_GUEST_KERNEL) {
491 			len -= ret;
492 			if (len) {
493 				pr_debug("Reducing len to %zu\n", len);
494 			} else if (dso__is_kcore(dso)) {
495 				/*
496 				 * objdump cannot handle very large segments
497 				 * that may be found in kcore.
498 				 */
499 				pr_debug("objdump failed for kcore");
500 				pr_debug(" - skipping\n");
501 			} else {
502 				err = -1;
503 			}
504 			goto out;
505 		}
506 	}
507 	if (ret < 0) {
508 		pr_debug("read_via_objdump failed\n");
509 		err = -1;
510 		goto out;
511 	}
512 
513 	/* The results should be identical */
514 	if (memcmp(buf1, buf2, len)) {
515 		pr_debug("Bytes read differ from those read by objdump\n");
516 		pr_debug("buf1 (dso):\n");
517 		dump_buf(buf1, len);
518 		pr_debug("buf2 (objdump):\n");
519 		dump_buf(buf2, len);
520 		err = -1;
521 		goto out;
522 	}
523 	pr_debug("Bytes read match those read by objdump\n");
524 out:
525 	addr_location__exit(&al);
526 	return err;
527 }
528 
process_sample_event(struct machine * machine,struct evlist * evlist,union perf_event * event,struct rb_root * tested_sections)529 static int process_sample_event(struct machine *machine, struct evlist *evlist,
530 				union perf_event *event,
531 				struct rb_root *tested_sections)
532 {
533 	struct perf_sample sample;
534 	struct thread *thread;
535 	int ret;
536 
537 	perf_sample__init(&sample, /*all=*/false);
538 	ret = evlist__parse_sample(evlist, event, &sample);
539 	if (ret) {
540 		pr_debug("evlist__parse_sample failed\n");
541 		ret = -1;
542 		goto out;
543 	}
544 
545 	thread = machine__findnew_thread(machine, sample.pid, sample.tid);
546 	if (!thread) {
547 		pr_debug("machine__findnew_thread failed\n");
548 		ret = -1;
549 		goto out;
550 	}
551 
552 	ret = read_object_code(sample.ip, READLEN, sample.cpumode, thread,
553 			       tested_sections);
554 	thread__put(thread);
555 out:
556 	perf_sample__exit(&sample);
557 	return ret;
558 }
559 
process_event(struct machine * machine,struct evlist * evlist,union perf_event * event,struct rb_root * tested_sections)560 static int process_event(struct machine *machine, struct evlist *evlist,
561 			 union perf_event *event, struct rb_root *tested_sections)
562 {
563 	if (event->header.type == PERF_RECORD_SAMPLE)
564 		return process_sample_event(machine, evlist, event,
565 					    tested_sections);
566 
567 	if (event->header.type == PERF_RECORD_THROTTLE ||
568 	    event->header.type == PERF_RECORD_UNTHROTTLE)
569 		return 0;
570 
571 	if (event->header.type < PERF_RECORD_MAX) {
572 		int ret;
573 
574 		ret = machine__process_event(machine, event, NULL);
575 		if (ret < 0)
576 			pr_debug("machine__process_event failed, event type %u\n",
577 				 event->header.type);
578 		return ret;
579 	}
580 
581 	return 0;
582 }
583 
process_events(struct machine * machine,struct evlist * evlist,struct rb_root * tested_sections)584 static int process_events(struct machine *machine, struct evlist *evlist,
585 			  struct rb_root *tested_sections)
586 {
587 	union perf_event *event;
588 	struct mmap *md;
589 	int i, ret;
590 
591 	for (i = 0; i < evlist->core.nr_mmaps; i++) {
592 		md = &evlist->mmap[i];
593 		if (perf_mmap__read_init(&md->core) < 0)
594 			continue;
595 
596 		while ((event = perf_mmap__read_event(&md->core)) != NULL) {
597 			ret = process_event(machine, evlist, event, tested_sections);
598 			perf_mmap__consume(&md->core);
599 			if (ret < 0)
600 				return ret;
601 		}
602 		perf_mmap__read_done(&md->core);
603 	}
604 	return 0;
605 }
606 
comp(const void * a,const void * b)607 static int comp(const void *a, const void *b)
608 {
609 	return *(int *)a - *(int *)b;
610 }
611 
do_sort_something(void)612 static void do_sort_something(void)
613 {
614 	int buf[40960], i;
615 
616 	for (i = 0; i < (int)ARRAY_SIZE(buf); i++)
617 		buf[i] = ARRAY_SIZE(buf) - i - 1;
618 
619 	qsort(buf, ARRAY_SIZE(buf), sizeof(int), comp);
620 
621 	for (i = 0; i < (int)ARRAY_SIZE(buf); i++) {
622 		if (buf[i] != i) {
623 			pr_debug("qsort failed\n");
624 			break;
625 		}
626 	}
627 }
628 
sort_something(void)629 static void sort_something(void)
630 {
631 	int i;
632 
633 	for (i = 0; i < 10; i++)
634 		do_sort_something();
635 }
636 
syscall_something(void)637 static void syscall_something(void)
638 {
639 	int pipefd[2];
640 	int i;
641 
642 	for (i = 0; i < 1000; i++) {
643 		if (pipe(pipefd) < 0) {
644 			pr_debug("pipe failed\n");
645 			break;
646 		}
647 		close(pipefd[1]);
648 		close(pipefd[0]);
649 	}
650 }
651 
fs_something(void)652 static void fs_something(void)
653 {
654 	const char *test_file_name = "temp-perf-code-reading-test-file--";
655 	FILE *f;
656 	int i;
657 
658 	for (i = 0; i < 1000; i++) {
659 		f = fopen(test_file_name, "w+");
660 		if (f) {
661 			fclose(f);
662 			unlink(test_file_name);
663 		}
664 	}
665 }
666 
do_something(void)667 static void do_something(void)
668 {
669 	fs_something();
670 
671 	sort_something();
672 
673 	syscall_something();
674 }
675 
676 enum {
677 	TEST_CODE_READING_OK,
678 	TEST_CODE_READING_NO_VMLINUX,
679 	TEST_CODE_READING_NO_KCORE,
680 	TEST_CODE_READING_NO_ACCESS,
681 	TEST_CODE_READING_NO_KERNEL_OBJ,
682 };
683 
do_test_code_reading(bool try_kcore)684 static int do_test_code_reading(bool try_kcore)
685 {
686 	struct machine *machine;
687 	struct thread *thread;
688 	struct record_opts opts = {
689 		.mmap_pages	     = UINT_MAX,
690 		.user_freq	     = UINT_MAX,
691 		.user_interval	     = ULLONG_MAX,
692 		.freq		     = 500,
693 		.target		     = {
694 			.uses_mmap   = true,
695 		},
696 	};
697 	struct rb_root tested_sections = RB_ROOT;
698 	struct perf_thread_map *threads = NULL;
699 	struct perf_cpu_map *cpus = NULL;
700 	struct evlist *evlist = NULL;
701 	struct evsel *evsel = NULL;
702 	int err = -1, ret;
703 	pid_t pid;
704 	struct map *map;
705 	bool have_vmlinux, have_kcore;
706 	struct dso *dso;
707 	const char *events[] = { "cpu-cycles", "cpu-cycles:u", "cpu-clock", "cpu-clock:u", NULL };
708 	int evidx = 0;
709 	struct perf_env host_env;
710 
711 	pid = getpid();
712 
713 	perf_env__init(&host_env);
714 	machine = machine__new_host(&host_env);
715 
716 	ret = machine__create_kernel_maps(machine);
717 	if (ret < 0) {
718 		pr_debug("machine__create_kernel_maps failed\n");
719 		goto out_err;
720 	}
721 
722 	/* Force the use of kallsyms instead of vmlinux to try kcore */
723 	if (try_kcore)
724 		symbol_conf.kallsyms_name = "/proc/kallsyms";
725 
726 	/* Load kernel map */
727 	map = machine__kernel_map(machine);
728 	ret = map__load(map);
729 	if (ret < 0) {
730 		pr_debug("map__load failed\n");
731 		goto out_err;
732 	}
733 	dso = map__dso(map);
734 	have_vmlinux = dso__is_vmlinux(dso);
735 	have_kcore = dso__is_kcore(dso);
736 
737 	/* 2nd time through we just try kcore */
738 	if (try_kcore && !have_kcore)
739 		return TEST_CODE_READING_NO_KCORE;
740 
741 	/* No point getting kernel events if there is no kernel object */
742 	if (!have_vmlinux && !have_kcore)
743 		evidx++;
744 
745 	threads = thread_map__new_by_tid(pid);
746 	if (!threads) {
747 		pr_debug("thread_map__new_by_tid failed\n");
748 		goto out_err;
749 	}
750 
751 	ret = perf_event__synthesize_thread_map(NULL, threads,
752 						perf_event__process, machine,
753 						true, false);
754 	if (ret < 0) {
755 		pr_debug("perf_event__synthesize_thread_map failed\n");
756 		goto out_err;
757 	}
758 
759 	thread = machine__findnew_thread(machine, pid, pid);
760 	if (!thread) {
761 		pr_debug("machine__findnew_thread failed\n");
762 		goto out_put;
763 	}
764 
765 	cpus = perf_cpu_map__new_online_cpus();
766 	if (!cpus) {
767 		pr_debug("perf_cpu_map__new failed\n");
768 		goto out_put;
769 	}
770 
771 	while (events[evidx]) {
772 		const char *str;
773 
774 		evlist = evlist__new();
775 		if (!evlist) {
776 			pr_debug("evlist__new failed\n");
777 			goto out_put;
778 		}
779 
780 		perf_evlist__set_maps(&evlist->core, cpus, threads);
781 
782 		str = events[evidx];
783 		pr_debug("Parsing event '%s'\n", str);
784 		ret = parse_event(evlist, str);
785 		if (ret < 0) {
786 			pr_debug("parse_events failed\n");
787 			goto out_put;
788 		}
789 
790 		evlist__config(evlist, &opts, NULL);
791 
792 		evlist__for_each_entry(evlist, evsel) {
793 			evsel->core.attr.comm = 1;
794 			evsel->core.attr.disabled = 1;
795 			evsel->core.attr.enable_on_exec = 0;
796 		}
797 
798 		ret = evlist__open(evlist);
799 		if (ret < 0) {
800 			evidx++;
801 
802 			if (events[evidx] == NULL && verbose > 0) {
803 				char errbuf[512];
804 				evlist__strerror_open(evlist, errno, errbuf, sizeof(errbuf));
805 				pr_debug("perf_evlist__open() failed!\n%s\n", errbuf);
806 			}
807 
808 			perf_evlist__set_maps(&evlist->core, NULL, NULL);
809 			evlist__delete(evlist);
810 			evlist = NULL;
811 			continue;
812 		}
813 		break;
814 	}
815 
816 	if (events[evidx] == NULL)
817 		goto out_put;
818 
819 	ret = evlist__mmap(evlist, UINT_MAX);
820 	if (ret < 0) {
821 		pr_debug("evlist__mmap failed\n");
822 		goto out_put;
823 	}
824 
825 	evlist__enable(evlist);
826 
827 	do_something();
828 
829 	evlist__disable(evlist);
830 
831 	ret = process_events(machine, evlist, &tested_sections);
832 	if (ret < 0)
833 		goto out_put;
834 
835 	if (!have_vmlinux && !have_kcore && !try_kcore)
836 		err = TEST_CODE_READING_NO_KERNEL_OBJ;
837 	else if (!have_vmlinux && !try_kcore)
838 		err = TEST_CODE_READING_NO_VMLINUX;
839 	else if (strstr(events[evidx], ":u"))
840 		err = TEST_CODE_READING_NO_ACCESS;
841 	else
842 		err = TEST_CODE_READING_OK;
843 out_put:
844 	thread__put(thread);
845 out_err:
846 	evlist__delete(evlist);
847 	perf_cpu_map__put(cpus);
848 	perf_thread_map__put(threads);
849 	machine__delete(machine);
850 	perf_env__exit(&host_env);
851 	tested_sections__free(&tested_sections);
852 
853 	return err;
854 }
855 
test__code_reading(struct test_suite * test __maybe_unused,int subtest __maybe_unused)856 static int test__code_reading(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
857 {
858 	int ret;
859 
860 	ret = do_test_code_reading(false);
861 	if (!ret)
862 		ret = do_test_code_reading(true);
863 
864 	switch (ret) {
865 	case TEST_CODE_READING_OK:
866 		return 0;
867 	case TEST_CODE_READING_NO_VMLINUX:
868 		pr_debug("no vmlinux\n");
869 		return 0;
870 	case TEST_CODE_READING_NO_KCORE:
871 		pr_debug("no kcore\n");
872 		return 0;
873 	case TEST_CODE_READING_NO_ACCESS:
874 		pr_debug("no access\n");
875 		return 0;
876 	case TEST_CODE_READING_NO_KERNEL_OBJ:
877 		pr_debug("no kernel obj\n");
878 		return 0;
879 	default:
880 		return -1;
881 	};
882 }
883 
884 DEFINE_SUITE("Object code reading", code_reading);
885