1 #include <linux/types.h>
8 #include "parse-events.h"
11 #include "thread_map.h"
27 static unsigned int hex(char c)
29 if (c >= '0' && c <= '9')
31 if (c >= 'a' && c <= 'f')
36 static size_t read_objdump_chunk(const char **line, unsigned char **buf,
39 size_t bytes_read = 0;
40 unsigned char *chunk_start = *buf;
43 while (*buf_len > 0) {
46 /* Get 2 hex digits */
54 /* Store byte and advance buf */
55 **buf = (hex(c1) << 4) | hex(c2);
66 * objdump will display raw insn as LE if code endian
67 * is LE and bytes_per_chunk > 1. In that case reverse
68 * the chunk we just read.
70 * see disassemble_bytes() at binutils/objdump.c for details
71 * how objdump chooses display endian)
73 if (bytes_read > 1 && !bigendian()) {
74 unsigned char *chunk_end = chunk_start + bytes_read - 1;
77 while (chunk_start < chunk_end) {
79 *chunk_start = *chunk_end;
89 static size_t read_objdump_line(const char *line, unsigned char *buf,
93 size_t ret, bytes_read = 0;
96 p = strchr(line, ':');
101 /* Skip initial spaces */
109 ret = read_objdump_chunk(&p, &buf, &buf_len);
114 /* return number of successfully read bytes */
118 static int read_objdump_output(FILE *f, void *buf, size_t *len, u64 start_addr)
121 size_t line_len, off_last = 0;
124 u64 addr, last_addr = start_addr;
126 while (off_last < *len) {
127 size_t off, read_bytes, written_bytes;
128 unsigned char tmp[BUFSZ];
130 ret = getline(&line, &line_len, f);
134 pr_debug("getline failed\n");
139 /* read objdump data into temporary buffer */
140 read_bytes = read_objdump_line(line, tmp, sizeof(tmp));
144 if (sscanf(line, "%"PRIx64, &addr) != 1)
146 if (addr < last_addr) {
147 pr_debug("addr going backwards, read beyond section?\n");
152 /* copy it from temporary buffer to 'buf' according
153 * to address on current objdump line */
154 off = addr - start_addr;
157 written_bytes = MIN(read_bytes, *len - off);
158 memcpy(buf + off, tmp, written_bytes);
159 off_last = off + written_bytes;
162 /* len returns number of bytes that could not be read */
170 static int read_via_objdump(const char *filename, u64 addr, void *buf,
173 char cmd[PATH_MAX * 2];
178 fmt = "%s -z -d --start-address=0x%"PRIx64" --stop-address=0x%"PRIx64" %s";
179 ret = snprintf(cmd, sizeof(cmd), fmt, "objdump", addr, addr + len,
181 if (ret <= 0 || (size_t)ret >= sizeof(cmd))
184 pr_debug("Objdump command is: %s\n", cmd);
186 /* Ignore objdump errors */
187 strcat(cmd, " 2>/dev/null");
191 pr_debug("popen failed\n");
195 ret = read_objdump_output(f, buf, &len, addr);
197 pr_debug("objdump read too few bytes: %zd\n", len);
207 static void dump_buf(unsigned char *buf, size_t len)
211 for (i = 0; i < len; i++) {
212 pr_debug("0x%02x ", buf[i]);
219 static int read_object_code(u64 addr, size_t len, u8 cpumode,
220 struct thread *thread, struct state *state)
222 struct addr_location al;
223 unsigned char buf1[BUFSZ];
224 unsigned char buf2[BUFSZ];
229 pr_debug("Reading object code for memory address: %#"PRIx64"\n", addr);
231 thread__find_addr_map(thread, cpumode, MAP__FUNCTION, addr, &al);
232 if (!al.map || !al.map->dso) {
233 pr_debug("thread__find_addr_map failed\n");
237 pr_debug("File is: %s\n", al.map->dso->long_name);
239 if (al.map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS &&
240 !dso__is_kcore(al.map->dso)) {
241 pr_debug("Unexpected kernel address - skipping\n");
245 pr_debug("On file address is: %#"PRIx64"\n", al.addr);
250 /* Do not go off the map */
251 if (addr + len > al.map->end)
252 len = al.map->end - addr;
254 /* Read the object code using perf */
255 ret_len = dso__data_read_offset(al.map->dso, thread->mg->machine,
257 if (ret_len != len) {
258 pr_debug("dso__data_read_offset failed\n");
263 * Converting addresses for use by objdump requires more information.
264 * map__load() does that. See map__rip_2objdump() for details.
266 if (map__load(al.map))
269 /* objdump struggles with kcore - try each map only once */
270 if (dso__is_kcore(al.map->dso)) {
273 for (d = 0; d < state->done_cnt; d++) {
274 if (state->done[d] == al.map->start) {
275 pr_debug("kcore map tested already");
276 pr_debug(" - skipping\n");
280 if (state->done_cnt >= ARRAY_SIZE(state->done)) {
281 pr_debug("Too many kcore maps - skipping\n");
284 state->done[state->done_cnt++] = al.map->start;
287 /* Read the object code using objdump */
288 objdump_addr = map__rip_2objdump(al.map, al.addr);
289 ret = read_via_objdump(al.map->dso->long_name, objdump_addr, buf2, len);
292 * The kernel maps are inaccurate - assume objdump is right in
295 if (cpumode == PERF_RECORD_MISC_KERNEL ||
296 cpumode == PERF_RECORD_MISC_GUEST_KERNEL) {
299 pr_debug("Reducing len to %zu\n", len);
300 } else if (dso__is_kcore(al.map->dso)) {
302 * objdump cannot handle very large segments
303 * that may be found in kcore.
305 pr_debug("objdump failed for kcore");
306 pr_debug(" - skipping\n");
314 pr_debug("read_via_objdump failed\n");
318 /* The results should be identical */
319 if (memcmp(buf1, buf2, len)) {
320 pr_debug("Bytes read differ from those read by objdump\n");
321 pr_debug("buf1 (dso):\n");
323 pr_debug("buf2 (objdump):\n");
327 pr_debug("Bytes read match those read by objdump\n");
332 static int process_sample_event(struct machine *machine,
333 struct perf_evlist *evlist,
334 union perf_event *event, struct state *state)
336 struct perf_sample sample;
337 struct thread *thread;
340 if (perf_evlist__parse_sample(evlist, event, &sample)) {
341 pr_debug("perf_evlist__parse_sample failed\n");
345 thread = machine__findnew_thread(machine, sample.pid, sample.tid);
347 pr_debug("machine__findnew_thread failed\n");
351 ret = read_object_code(sample.ip, READLEN, sample.cpumode, thread, state);
356 static int process_event(struct machine *machine, struct perf_evlist *evlist,
357 union perf_event *event, struct state *state)
359 if (event->header.type == PERF_RECORD_SAMPLE)
360 return process_sample_event(machine, evlist, event, state);
362 if (event->header.type == PERF_RECORD_THROTTLE ||
363 event->header.type == PERF_RECORD_UNTHROTTLE)
366 if (event->header.type < PERF_RECORD_MAX) {
369 ret = machine__process_event(machine, event, NULL);
371 pr_debug("machine__process_event failed, event type %u\n",
379 static int process_events(struct machine *machine, struct perf_evlist *evlist,
382 union perf_event *event;
385 for (i = 0; i < evlist->nr_mmaps; i++) {
386 while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
387 ret = process_event(machine, evlist, event, state);
388 perf_evlist__mmap_consume(evlist, i);
396 static int comp(const void *a, const void *b)
398 return *(int *)a - *(int *)b;
401 static void do_sort_something(void)
405 for (i = 0; i < (int)ARRAY_SIZE(buf); i++)
406 buf[i] = ARRAY_SIZE(buf) - i - 1;
408 qsort(buf, ARRAY_SIZE(buf), sizeof(int), comp);
410 for (i = 0; i < (int)ARRAY_SIZE(buf); i++) {
412 pr_debug("qsort failed\n");
418 static void sort_something(void)
422 for (i = 0; i < 10; i++)
426 static void syscall_something(void)
431 for (i = 0; i < 1000; i++) {
432 if (pipe(pipefd) < 0) {
433 pr_debug("pipe failed\n");
441 static void fs_something(void)
443 const char *test_file_name = "temp-perf-code-reading-test-file--";
447 for (i = 0; i < 1000; i++) {
448 f = fopen(test_file_name, "w+");
451 unlink(test_file_name);
456 static void do_something(void)
466 TEST_CODE_READING_OK,
467 TEST_CODE_READING_NO_VMLINUX,
468 TEST_CODE_READING_NO_KCORE,
469 TEST_CODE_READING_NO_ACCESS,
470 TEST_CODE_READING_NO_KERNEL_OBJ,
473 static int do_test_code_reading(bool try_kcore)
475 struct machine *machine;
476 struct thread *thread;
477 struct record_opts opts = {
478 .mmap_pages = UINT_MAX,
479 .user_freq = UINT_MAX,
480 .user_interval = ULLONG_MAX,
486 struct state state = {
489 struct thread_map *threads = NULL;
490 struct cpu_map *cpus = NULL;
491 struct perf_evlist *evlist = NULL;
492 struct perf_evsel *evsel = NULL;
496 bool have_vmlinux, have_kcore, excl_kernel = false;
500 machine = machine__new_host();
502 ret = machine__create_kernel_maps(machine);
504 pr_debug("machine__create_kernel_maps failed\n");
508 /* Force the use of kallsyms instead of vmlinux to try kcore */
510 symbol_conf.kallsyms_name = "/proc/kallsyms";
512 /* Load kernel map */
513 map = machine__kernel_map(machine);
514 ret = map__load(map);
516 pr_debug("map__load failed\n");
519 have_vmlinux = dso__is_vmlinux(map->dso);
520 have_kcore = dso__is_kcore(map->dso);
522 /* 2nd time through we just try kcore */
523 if (try_kcore && !have_kcore)
524 return TEST_CODE_READING_NO_KCORE;
526 /* No point getting kernel events if there is no kernel object */
527 if (!have_vmlinux && !have_kcore)
530 threads = thread_map__new_by_tid(pid);
532 pr_debug("thread_map__new_by_tid failed\n");
536 ret = perf_event__synthesize_thread_map(NULL, threads,
537 perf_event__process, machine, false, 500);
539 pr_debug("perf_event__synthesize_thread_map failed\n");
543 thread = machine__findnew_thread(machine, pid, pid);
545 pr_debug("machine__findnew_thread failed\n");
549 cpus = cpu_map__new(NULL);
551 pr_debug("cpu_map__new failed\n");
558 evlist = perf_evlist__new();
560 pr_debug("perf_evlist__new failed\n");
564 perf_evlist__set_maps(evlist, cpus, threads);
570 pr_debug("Parsing event '%s'\n", str);
571 ret = parse_events(evlist, str, NULL);
573 pr_debug("parse_events failed\n");
577 perf_evlist__config(evlist, &opts, NULL);
579 evsel = perf_evlist__first(evlist);
581 evsel->attr.comm = 1;
582 evsel->attr.disabled = 1;
583 evsel->attr.enable_on_exec = 0;
585 ret = perf_evlist__open(evlist);
590 * Both cpus and threads are now owned by evlist
591 * and will be freed by following perf_evlist__set_maps
592 * call. Getting refference to keep them alive.
595 thread_map__get(threads);
596 perf_evlist__set_maps(evlist, NULL, NULL);
597 perf_evlist__delete(evlist);
604 perf_evlist__strerror_open(evlist, errno, errbuf, sizeof(errbuf));
605 pr_debug("perf_evlist__open() failed!\n%s\n", errbuf);
613 ret = perf_evlist__mmap(evlist, UINT_MAX, false);
615 pr_debug("perf_evlist__mmap failed\n");
619 perf_evlist__enable(evlist);
623 perf_evlist__disable(evlist);
625 ret = process_events(machine, evlist, &state);
629 if (!have_vmlinux && !have_kcore && !try_kcore)
630 err = TEST_CODE_READING_NO_KERNEL_OBJ;
631 else if (!have_vmlinux && !try_kcore)
632 err = TEST_CODE_READING_NO_VMLINUX;
633 else if (excl_kernel)
634 err = TEST_CODE_READING_NO_ACCESS;
636 err = TEST_CODE_READING_OK;
642 perf_evlist__delete(evlist);
645 thread_map__put(threads);
647 machine__delete_threads(machine);
648 machine__delete(machine);
653 int test__code_reading(int subtest __maybe_unused)
657 ret = do_test_code_reading(false);
659 ret = do_test_code_reading(true);
662 case TEST_CODE_READING_OK:
664 case TEST_CODE_READING_NO_VMLINUX:
665 pr_debug("no vmlinux\n");
667 case TEST_CODE_READING_NO_KCORE:
668 pr_debug("no kcore\n");
670 case TEST_CODE_READING_NO_ACCESS:
671 pr_debug("no access\n");
673 case TEST_CODE_READING_NO_KERNEL_OBJ:
674 pr_debug("no kernel obj\n");