Linux 5.1.15
[linux/fpc-iii.git] / tools / perf / tests / code-reading.c
blob4ebd2681e7607c2efda177eb3f9f6956f8082bba
1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <linux/kernel.h>
4 #include <linux/types.h>
5 #include <inttypes.h>
6 #include <stdlib.h>
7 #include <unistd.h>
8 #include <stdio.h>
9 #include <string.h>
10 #include <sys/param.h>
12 #include "parse-events.h"
13 #include "evlist.h"
14 #include "evsel.h"
15 #include "thread_map.h"
16 #include "cpumap.h"
17 #include "machine.h"
18 #include "map.h"
19 #include "symbol.h"
20 #include "event.h"
21 #include "thread.h"
23 #include "tests.h"
25 #include "sane_ctype.h"
27 #define BUFSZ 1024
28 #define READLEN 128
30 struct state {
31 u64 done[1024];
32 size_t done_cnt;
35 static unsigned int hex(char c)
37 if (c >= '0' && c <= '9')
38 return c - '0';
39 if (c >= 'a' && c <= 'f')
40 return c - 'a' + 10;
41 return c - 'A' + 10;
44 static size_t read_objdump_chunk(const char **line, unsigned char **buf,
45 size_t *buf_len)
47 size_t bytes_read = 0;
48 unsigned char *chunk_start = *buf;
50 /* Read bytes */
51 while (*buf_len > 0) {
52 char c1, c2;
54 /* Get 2 hex digits */
55 c1 = *(*line)++;
56 if (!isxdigit(c1))
57 break;
58 c2 = *(*line)++;
59 if (!isxdigit(c2))
60 break;
62 /* Store byte and advance buf */
63 **buf = (hex(c1) << 4) | hex(c2);
64 (*buf)++;
65 (*buf_len)--;
66 bytes_read++;
68 /* End of chunk? */
69 if (isspace(**line))
70 break;
74 * objdump will display raw insn as LE if code endian
75 * is LE and bytes_per_chunk > 1. In that case reverse
76 * the chunk we just read.
78 * see disassemble_bytes() at binutils/objdump.c for details
79 * how objdump chooses display endian)
81 if (bytes_read > 1 && !bigendian()) {
82 unsigned char *chunk_end = chunk_start + bytes_read - 1;
83 unsigned char tmp;
85 while (chunk_start < chunk_end) {
86 tmp = *chunk_start;
87 *chunk_start = *chunk_end;
88 *chunk_end = tmp;
89 chunk_start++;
90 chunk_end--;
94 return bytes_read;
97 static size_t read_objdump_line(const char *line, unsigned char *buf,
98 size_t buf_len)
100 const char *p;
101 size_t ret, bytes_read = 0;
103 /* Skip to a colon */
104 p = strchr(line, ':');
105 if (!p)
106 return 0;
107 p++;
109 /* Skip initial spaces */
110 while (*p) {
111 if (!isspace(*p))
112 break;
113 p++;
116 do {
117 ret = read_objdump_chunk(&p, &buf, &buf_len);
118 bytes_read += ret;
119 p++;
120 } while (ret > 0);
122 /* return number of successfully read bytes */
123 return bytes_read;
126 static int read_objdump_output(FILE *f, void *buf, size_t *len, u64 start_addr)
128 char *line = NULL;
129 size_t line_len, off_last = 0;
130 ssize_t ret;
131 int err = 0;
132 u64 addr, last_addr = start_addr;
134 while (off_last < *len) {
135 size_t off, read_bytes, written_bytes;
136 unsigned char tmp[BUFSZ];
138 ret = getline(&line, &line_len, f);
139 if (feof(f))
140 break;
141 if (ret < 0) {
142 pr_debug("getline failed\n");
143 err = -1;
144 break;
147 /* read objdump data into temporary buffer */
148 read_bytes = read_objdump_line(line, tmp, sizeof(tmp));
149 if (!read_bytes)
150 continue;
152 if (sscanf(line, "%"PRIx64, &addr) != 1)
153 continue;
154 if (addr < last_addr) {
155 pr_debug("addr going backwards, read beyond section?\n");
156 break;
158 last_addr = addr;
160 /* copy it from temporary buffer to 'buf' according
161 * to address on current objdump line */
162 off = addr - start_addr;
163 if (off >= *len)
164 break;
165 written_bytes = MIN(read_bytes, *len - off);
166 memcpy(buf + off, tmp, written_bytes);
167 off_last = off + written_bytes;
170 /* len returns number of bytes that could not be read */
171 *len -= off_last;
173 free(line);
175 return err;
178 static int read_via_objdump(const char *filename, u64 addr, void *buf,
179 size_t len)
181 char cmd[PATH_MAX * 2];
182 const char *fmt;
183 FILE *f;
184 int ret;
186 fmt = "%s -z -d --start-address=0x%"PRIx64" --stop-address=0x%"PRIx64" %s";
187 ret = snprintf(cmd, sizeof(cmd), fmt, "objdump", addr, addr + len,
188 filename);
189 if (ret <= 0 || (size_t)ret >= sizeof(cmd))
190 return -1;
192 pr_debug("Objdump command is: %s\n", cmd);
194 /* Ignore objdump errors */
195 strcat(cmd, " 2>/dev/null");
197 f = popen(cmd, "r");
198 if (!f) {
199 pr_debug("popen failed\n");
200 return -1;
203 ret = read_objdump_output(f, buf, &len, addr);
204 if (len) {
205 pr_debug("objdump read too few bytes: %zd\n", len);
206 if (!ret)
207 ret = len;
210 pclose(f);
212 return ret;
215 static void dump_buf(unsigned char *buf, size_t len)
217 size_t i;
219 for (i = 0; i < len; i++) {
220 pr_debug("0x%02x ", buf[i]);
221 if (i % 16 == 15)
222 pr_debug("\n");
224 pr_debug("\n");
227 static int read_object_code(u64 addr, size_t len, u8 cpumode,
228 struct thread *thread, struct state *state)
230 struct addr_location al;
231 unsigned char buf1[BUFSZ];
232 unsigned char buf2[BUFSZ];
233 size_t ret_len;
234 u64 objdump_addr;
235 const char *objdump_name;
236 char decomp_name[KMOD_DECOMP_LEN];
237 bool decomp = false;
238 int ret;
240 pr_debug("Reading object code for memory address: %#"PRIx64"\n", addr);
242 if (!thread__find_map(thread, cpumode, addr, &al) || !al.map->dso) {
243 if (cpumode == PERF_RECORD_MISC_HYPERVISOR) {
244 pr_debug("Hypervisor address can not be resolved - skipping\n");
245 return 0;
248 pr_debug("thread__find_map failed\n");
249 return -1;
252 pr_debug("File is: %s\n", al.map->dso->long_name);
254 if (al.map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS &&
255 !dso__is_kcore(al.map->dso)) {
256 pr_debug("Unexpected kernel address - skipping\n");
257 return 0;
260 pr_debug("On file address is: %#"PRIx64"\n", al.addr);
262 if (len > BUFSZ)
263 len = BUFSZ;
265 /* Do not go off the map */
266 if (addr + len > al.map->end)
267 len = al.map->end - addr;
269 /* Read the object code using perf */
270 ret_len = dso__data_read_offset(al.map->dso, thread->mg->machine,
271 al.addr, buf1, len);
272 if (ret_len != len) {
273 pr_debug("dso__data_read_offset failed\n");
274 return -1;
278 * Converting addresses for use by objdump requires more information.
279 * map__load() does that. See map__rip_2objdump() for details.
281 if (map__load(al.map))
282 return -1;
284 /* objdump struggles with kcore - try each map only once */
285 if (dso__is_kcore(al.map->dso)) {
286 size_t d;
288 for (d = 0; d < state->done_cnt; d++) {
289 if (state->done[d] == al.map->start) {
290 pr_debug("kcore map tested already");
291 pr_debug(" - skipping\n");
292 return 0;
295 if (state->done_cnt >= ARRAY_SIZE(state->done)) {
296 pr_debug("Too many kcore maps - skipping\n");
297 return 0;
299 state->done[state->done_cnt++] = al.map->start;
302 objdump_name = al.map->dso->long_name;
303 if (dso__needs_decompress(al.map->dso)) {
304 if (dso__decompress_kmodule_path(al.map->dso, objdump_name,
305 decomp_name,
306 sizeof(decomp_name)) < 0) {
307 pr_debug("decompression failed\n");
308 return -1;
311 decomp = true;
312 objdump_name = decomp_name;
315 /* Read the object code using objdump */
316 objdump_addr = map__rip_2objdump(al.map, al.addr);
317 ret = read_via_objdump(objdump_name, objdump_addr, buf2, len);
319 if (decomp)
320 unlink(objdump_name);
322 if (ret > 0) {
324 * The kernel maps are inaccurate - assume objdump is right in
325 * that case.
327 if (cpumode == PERF_RECORD_MISC_KERNEL ||
328 cpumode == PERF_RECORD_MISC_GUEST_KERNEL) {
329 len -= ret;
330 if (len) {
331 pr_debug("Reducing len to %zu\n", len);
332 } else if (dso__is_kcore(al.map->dso)) {
334 * objdump cannot handle very large segments
335 * that may be found in kcore.
337 pr_debug("objdump failed for kcore");
338 pr_debug(" - skipping\n");
339 return 0;
340 } else {
341 return -1;
345 if (ret < 0) {
346 pr_debug("read_via_objdump failed\n");
347 return -1;
350 /* The results should be identical */
351 if (memcmp(buf1, buf2, len)) {
352 pr_debug("Bytes read differ from those read by objdump\n");
353 pr_debug("buf1 (dso):\n");
354 dump_buf(buf1, len);
355 pr_debug("buf2 (objdump):\n");
356 dump_buf(buf2, len);
357 return -1;
359 pr_debug("Bytes read match those read by objdump\n");
361 return 0;
364 static int process_sample_event(struct machine *machine,
365 struct perf_evlist *evlist,
366 union perf_event *event, struct state *state)
368 struct perf_sample sample;
369 struct thread *thread;
370 int ret;
372 if (perf_evlist__parse_sample(evlist, event, &sample)) {
373 pr_debug("perf_evlist__parse_sample failed\n");
374 return -1;
377 thread = machine__findnew_thread(machine, sample.pid, sample.tid);
378 if (!thread) {
379 pr_debug("machine__findnew_thread failed\n");
380 return -1;
383 ret = read_object_code(sample.ip, READLEN, sample.cpumode, thread, state);
384 thread__put(thread);
385 return ret;
388 static int process_event(struct machine *machine, struct perf_evlist *evlist,
389 union perf_event *event, struct state *state)
391 if (event->header.type == PERF_RECORD_SAMPLE)
392 return process_sample_event(machine, evlist, event, state);
394 if (event->header.type == PERF_RECORD_THROTTLE ||
395 event->header.type == PERF_RECORD_UNTHROTTLE)
396 return 0;
398 if (event->header.type < PERF_RECORD_MAX) {
399 int ret;
401 ret = machine__process_event(machine, event, NULL);
402 if (ret < 0)
403 pr_debug("machine__process_event failed, event type %u\n",
404 event->header.type);
405 return ret;
408 return 0;
411 static int process_events(struct machine *machine, struct perf_evlist *evlist,
412 struct state *state)
414 union perf_event *event;
415 struct perf_mmap *md;
416 int i, ret;
418 for (i = 0; i < evlist->nr_mmaps; i++) {
419 md = &evlist->mmap[i];
420 if (perf_mmap__read_init(md) < 0)
421 continue;
423 while ((event = perf_mmap__read_event(md)) != NULL) {
424 ret = process_event(machine, evlist, event, state);
425 perf_mmap__consume(md);
426 if (ret < 0)
427 return ret;
429 perf_mmap__read_done(md);
431 return 0;
434 static int comp(const void *a, const void *b)
436 return *(int *)a - *(int *)b;
439 static void do_sort_something(void)
441 int buf[40960], i;
443 for (i = 0; i < (int)ARRAY_SIZE(buf); i++)
444 buf[i] = ARRAY_SIZE(buf) - i - 1;
446 qsort(buf, ARRAY_SIZE(buf), sizeof(int), comp);
448 for (i = 0; i < (int)ARRAY_SIZE(buf); i++) {
449 if (buf[i] != i) {
450 pr_debug("qsort failed\n");
451 break;
456 static void sort_something(void)
458 int i;
460 for (i = 0; i < 10; i++)
461 do_sort_something();
464 static void syscall_something(void)
466 int pipefd[2];
467 int i;
469 for (i = 0; i < 1000; i++) {
470 if (pipe(pipefd) < 0) {
471 pr_debug("pipe failed\n");
472 break;
474 close(pipefd[1]);
475 close(pipefd[0]);
479 static void fs_something(void)
481 const char *test_file_name = "temp-perf-code-reading-test-file--";
482 FILE *f;
483 int i;
485 for (i = 0; i < 1000; i++) {
486 f = fopen(test_file_name, "w+");
487 if (f) {
488 fclose(f);
489 unlink(test_file_name);
494 static const char *do_determine_event(bool excl_kernel)
496 const char *event = excl_kernel ? "cycles:u" : "cycles";
498 #ifdef __s390x__
499 char cpuid[128], model[16], model_c[16], cpum_cf_v[16];
500 unsigned int family;
501 int ret, cpum_cf_a;
503 if (get_cpuid(cpuid, sizeof(cpuid)))
504 goto out_clocks;
505 ret = sscanf(cpuid, "%*[^,],%u,%[^,],%[^,],%[^,],%x", &family, model_c,
506 model, cpum_cf_v, &cpum_cf_a);
507 if (ret != 5) /* Not available */
508 goto out_clocks;
509 if (excl_kernel && (cpum_cf_a & 4))
510 return event;
511 if (!excl_kernel && (cpum_cf_a & 2))
512 return event;
514 /* Fall through: missing authorization */
515 out_clocks:
516 event = excl_kernel ? "cpu-clock:u" : "cpu-clock";
518 #endif
519 return event;
522 static void do_something(void)
524 fs_something();
526 sort_something();
528 syscall_something();
531 enum {
532 TEST_CODE_READING_OK,
533 TEST_CODE_READING_NO_VMLINUX,
534 TEST_CODE_READING_NO_KCORE,
535 TEST_CODE_READING_NO_ACCESS,
536 TEST_CODE_READING_NO_KERNEL_OBJ,
539 static int do_test_code_reading(bool try_kcore)
541 struct machine *machine;
542 struct thread *thread;
543 struct record_opts opts = {
544 .mmap_pages = UINT_MAX,
545 .user_freq = UINT_MAX,
546 .user_interval = ULLONG_MAX,
547 .freq = 500,
548 .target = {
549 .uses_mmap = true,
552 struct state state = {
553 .done_cnt = 0,
555 struct thread_map *threads = NULL;
556 struct cpu_map *cpus = NULL;
557 struct perf_evlist *evlist = NULL;
558 struct perf_evsel *evsel = NULL;
559 int err = -1, ret;
560 pid_t pid;
561 struct map *map;
562 bool have_vmlinux, have_kcore, excl_kernel = false;
564 pid = getpid();
566 machine = machine__new_host();
567 machine->env = &perf_env;
569 ret = machine__create_kernel_maps(machine);
570 if (ret < 0) {
571 pr_debug("machine__create_kernel_maps failed\n");
572 goto out_err;
575 /* Force the use of kallsyms instead of vmlinux to try kcore */
576 if (try_kcore)
577 symbol_conf.kallsyms_name = "/proc/kallsyms";
579 /* Load kernel map */
580 map = machine__kernel_map(machine);
581 ret = map__load(map);
582 if (ret < 0) {
583 pr_debug("map__load failed\n");
584 goto out_err;
586 have_vmlinux = dso__is_vmlinux(map->dso);
587 have_kcore = dso__is_kcore(map->dso);
589 /* 2nd time through we just try kcore */
590 if (try_kcore && !have_kcore)
591 return TEST_CODE_READING_NO_KCORE;
593 /* No point getting kernel events if there is no kernel object */
594 if (!have_vmlinux && !have_kcore)
595 excl_kernel = true;
597 threads = thread_map__new_by_tid(pid);
598 if (!threads) {
599 pr_debug("thread_map__new_by_tid failed\n");
600 goto out_err;
603 ret = perf_event__synthesize_thread_map(NULL, threads,
604 perf_event__process, machine, false);
605 if (ret < 0) {
606 pr_debug("perf_event__synthesize_thread_map failed\n");
607 goto out_err;
610 thread = machine__findnew_thread(machine, pid, pid);
611 if (!thread) {
612 pr_debug("machine__findnew_thread failed\n");
613 goto out_put;
616 cpus = cpu_map__new(NULL);
617 if (!cpus) {
618 pr_debug("cpu_map__new failed\n");
619 goto out_put;
622 while (1) {
623 const char *str;
625 evlist = perf_evlist__new();
626 if (!evlist) {
627 pr_debug("perf_evlist__new failed\n");
628 goto out_put;
631 perf_evlist__set_maps(evlist, cpus, threads);
633 str = do_determine_event(excl_kernel);
634 pr_debug("Parsing event '%s'\n", str);
635 ret = parse_events(evlist, str, NULL);
636 if (ret < 0) {
637 pr_debug("parse_events failed\n");
638 goto out_put;
641 perf_evlist__config(evlist, &opts, NULL);
643 evsel = perf_evlist__first(evlist);
645 evsel->attr.comm = 1;
646 evsel->attr.disabled = 1;
647 evsel->attr.enable_on_exec = 0;
649 ret = perf_evlist__open(evlist);
650 if (ret < 0) {
651 if (!excl_kernel) {
652 excl_kernel = true;
654 * Both cpus and threads are now owned by evlist
655 * and will be freed by following perf_evlist__set_maps
656 * call. Getting refference to keep them alive.
658 cpu_map__get(cpus);
659 thread_map__get(threads);
660 perf_evlist__set_maps(evlist, NULL, NULL);
661 perf_evlist__delete(evlist);
662 evlist = NULL;
663 continue;
666 if (verbose > 0) {
667 char errbuf[512];
668 perf_evlist__strerror_open(evlist, errno, errbuf, sizeof(errbuf));
669 pr_debug("perf_evlist__open() failed!\n%s\n", errbuf);
672 goto out_put;
674 break;
677 ret = perf_evlist__mmap(evlist, UINT_MAX);
678 if (ret < 0) {
679 pr_debug("perf_evlist__mmap failed\n");
680 goto out_put;
683 perf_evlist__enable(evlist);
685 do_something();
687 perf_evlist__disable(evlist);
689 ret = process_events(machine, evlist, &state);
690 if (ret < 0)
691 goto out_put;
693 if (!have_vmlinux && !have_kcore && !try_kcore)
694 err = TEST_CODE_READING_NO_KERNEL_OBJ;
695 else if (!have_vmlinux && !try_kcore)
696 err = TEST_CODE_READING_NO_VMLINUX;
697 else if (excl_kernel)
698 err = TEST_CODE_READING_NO_ACCESS;
699 else
700 err = TEST_CODE_READING_OK;
701 out_put:
702 thread__put(thread);
703 out_err:
705 if (evlist) {
706 perf_evlist__delete(evlist);
707 } else {
708 cpu_map__put(cpus);
709 thread_map__put(threads);
711 machine__delete_threads(machine);
712 machine__delete(machine);
714 return err;
717 int test__code_reading(struct test *test __maybe_unused, int subtest __maybe_unused)
719 int ret;
721 ret = do_test_code_reading(false);
722 if (!ret)
723 ret = do_test_code_reading(true);
725 switch (ret) {
726 case TEST_CODE_READING_OK:
727 return 0;
728 case TEST_CODE_READING_NO_VMLINUX:
729 pr_debug("no vmlinux\n");
730 return 0;
731 case TEST_CODE_READING_NO_KCORE:
732 pr_debug("no kcore\n");
733 return 0;
734 case TEST_CODE_READING_NO_ACCESS:
735 pr_debug("no access\n");
736 return 0;
737 case TEST_CODE_READING_NO_KERNEL_OBJ:
738 pr_debug("no kernel obj\n");
739 return 0;
740 default:
741 return -1;