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 void read_objdump_line(const char *line, size_t line_len, void **buf,
43 p = strchr(line, ':');
53 for (; i < line_len; i++) {
54 if (!isspace(line[i]))
57 /* Get 2 hex digits */
58 if (i >= line_len || !isxdigit(line[i]))
61 if (i >= line_len || !isxdigit(line[i]))
64 /* Followed by a space */
65 if (i < line_len && line[i] && !isspace(line[i]))
68 *(unsigned char *)*buf = (hex(c1) << 4) | hex(c2);
74 static int read_objdump_output(FILE *f, void **buf, size_t *len)
82 ret = getline(&line, &line_len, f);
86 pr_debug("getline failed\n");
90 read_objdump_line(line, ret, buf, len);
98 static int read_via_objdump(const char *filename, u64 addr, void *buf,
101 char cmd[PATH_MAX * 2];
106 fmt = "%s -d --start-address=0x%"PRIx64" --stop-address=0x%"PRIx64" %s";
107 ret = snprintf(cmd, sizeof(cmd), fmt, "objdump", addr, addr + len,
109 if (ret <= 0 || (size_t)ret >= sizeof(cmd))
112 pr_debug("Objdump command is: %s\n", cmd);
114 /* Ignore objdump errors */
115 strcat(cmd, " 2>/dev/null");
119 pr_debug("popen failed\n");
123 ret = read_objdump_output(f, &buf, &len);
125 pr_debug("objdump read too few bytes\n");
135 static int read_object_code(u64 addr, size_t len, u8 cpumode,
136 struct thread *thread, struct state *state)
138 struct addr_location al;
139 unsigned char buf1[BUFSZ];
140 unsigned char buf2[BUFSZ];
145 pr_debug("Reading object code for memory address: %#"PRIx64"\n", addr);
147 thread__find_addr_map(thread, cpumode, MAP__FUNCTION, addr, &al);
148 if (!al.map || !al.map->dso) {
149 pr_debug("thread__find_addr_map failed\n");
153 pr_debug("File is: %s\n", al.map->dso->long_name);
155 if (al.map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS &&
156 !dso__is_kcore(al.map->dso)) {
157 pr_debug("Unexpected kernel address - skipping\n");
161 pr_debug("On file address is: %#"PRIx64"\n", al.addr);
166 /* Do not go off the map */
167 if (addr + len > al.map->end)
168 len = al.map->end - addr;
170 /* Read the object code using perf */
171 ret_len = dso__data_read_offset(al.map->dso, thread->mg->machine,
173 if (ret_len != len) {
174 pr_debug("dso__data_read_offset failed\n");
179 * Converting addresses for use by objdump requires more information.
180 * map__load() does that. See map__rip_2objdump() for details.
182 if (map__load(al.map, NULL))
185 /* objdump struggles with kcore - try each map only once */
186 if (dso__is_kcore(al.map->dso)) {
189 for (d = 0; d < state->done_cnt; d++) {
190 if (state->done[d] == al.map->start) {
191 pr_debug("kcore map tested already");
192 pr_debug(" - skipping\n");
196 if (state->done_cnt >= ARRAY_SIZE(state->done)) {
197 pr_debug("Too many kcore maps - skipping\n");
200 state->done[state->done_cnt++] = al.map->start;
203 /* Read the object code using objdump */
204 objdump_addr = map__rip_2objdump(al.map, al.addr);
205 ret = read_via_objdump(al.map->dso->long_name, objdump_addr, buf2, len);
208 * The kernel maps are inaccurate - assume objdump is right in
211 if (cpumode == PERF_RECORD_MISC_KERNEL ||
212 cpumode == PERF_RECORD_MISC_GUEST_KERNEL) {
215 pr_debug("Reducing len to %zu\n", len);
216 } else if (dso__is_kcore(al.map->dso)) {
218 * objdump cannot handle very large segments
219 * that may be found in kcore.
221 pr_debug("objdump failed for kcore");
222 pr_debug(" - skipping\n");
230 pr_debug("read_via_objdump failed\n");
234 /* The results should be identical */
235 if (memcmp(buf1, buf2, len)) {
236 pr_debug("Bytes read differ from those read by objdump\n");
239 pr_debug("Bytes read match those read by objdump\n");
244 static int process_sample_event(struct machine *machine,
245 struct perf_evlist *evlist,
246 union perf_event *event, struct state *state)
248 struct perf_sample sample;
249 struct thread *thread;
252 if (perf_evlist__parse_sample(evlist, event, &sample)) {
253 pr_debug("perf_evlist__parse_sample failed\n");
257 thread = machine__findnew_thread(machine, sample.pid, sample.tid);
259 pr_debug("machine__findnew_thread failed\n");
263 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
265 return read_object_code(sample.ip, READLEN, cpumode, thread, state);
268 static int process_event(struct machine *machine, struct perf_evlist *evlist,
269 union perf_event *event, struct state *state)
271 if (event->header.type == PERF_RECORD_SAMPLE)
272 return process_sample_event(machine, evlist, event, state);
274 if (event->header.type == PERF_RECORD_THROTTLE ||
275 event->header.type == PERF_RECORD_UNTHROTTLE)
278 if (event->header.type < PERF_RECORD_MAX) {
281 ret = machine__process_event(machine, event, NULL);
283 pr_debug("machine__process_event failed, event type %u\n",
291 static int process_events(struct machine *machine, struct perf_evlist *evlist,
294 union perf_event *event;
297 for (i = 0; i < evlist->nr_mmaps; i++) {
298 while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
299 ret = process_event(machine, evlist, event, state);
300 perf_evlist__mmap_consume(evlist, i);
308 static int comp(const void *a, const void *b)
310 return *(int *)a - *(int *)b;
313 static void do_sort_something(void)
317 for (i = 0; i < (int)ARRAY_SIZE(buf); i++)
318 buf[i] = ARRAY_SIZE(buf) - i - 1;
320 qsort(buf, ARRAY_SIZE(buf), sizeof(int), comp);
322 for (i = 0; i < (int)ARRAY_SIZE(buf); i++) {
324 pr_debug("qsort failed\n");
330 static void sort_something(void)
334 for (i = 0; i < 10; i++)
338 static void syscall_something(void)
343 for (i = 0; i < 1000; i++) {
344 if (pipe(pipefd) < 0) {
345 pr_debug("pipe failed\n");
353 static void fs_something(void)
355 const char *test_file_name = "temp-perf-code-reading-test-file--";
359 for (i = 0; i < 1000; i++) {
360 f = fopen(test_file_name, "w+");
363 unlink(test_file_name);
368 static void do_something(void)
378 TEST_CODE_READING_OK,
379 TEST_CODE_READING_NO_VMLINUX,
380 TEST_CODE_READING_NO_KCORE,
381 TEST_CODE_READING_NO_ACCESS,
382 TEST_CODE_READING_NO_KERNEL_OBJ,
385 static int do_test_code_reading(bool try_kcore)
387 struct machines machines;
388 struct machine *machine;
389 struct thread *thread;
390 struct record_opts opts = {
391 .mmap_pages = UINT_MAX,
392 .user_freq = UINT_MAX,
393 .user_interval = ULLONG_MAX,
399 struct state state = {
402 struct thread_map *threads = NULL;
403 struct cpu_map *cpus = NULL;
404 struct perf_evlist *evlist = NULL;
405 struct perf_evsel *evsel = NULL;
409 bool have_vmlinux, have_kcore, excl_kernel = false;
413 machines__init(&machines);
414 machine = &machines.host;
416 ret = machine__create_kernel_maps(machine);
418 pr_debug("machine__create_kernel_maps failed\n");
422 /* Force the use of kallsyms instead of vmlinux to try kcore */
424 symbol_conf.kallsyms_name = "/proc/kallsyms";
426 /* Load kernel map */
427 map = machine->vmlinux_maps[MAP__FUNCTION];
428 ret = map__load(map, NULL);
430 pr_debug("map__load failed\n");
433 have_vmlinux = dso__is_vmlinux(map->dso);
434 have_kcore = dso__is_kcore(map->dso);
436 /* 2nd time through we just try kcore */
437 if (try_kcore && !have_kcore)
438 return TEST_CODE_READING_NO_KCORE;
440 /* No point getting kernel events if there is no kernel object */
441 if (!have_vmlinux && !have_kcore)
444 threads = thread_map__new_by_tid(pid);
446 pr_debug("thread_map__new_by_tid failed\n");
450 ret = perf_event__synthesize_thread_map(NULL, threads,
451 perf_event__process, machine, false);
453 pr_debug("perf_event__synthesize_thread_map failed\n");
457 thread = machine__findnew_thread(machine, pid, pid);
459 pr_debug("machine__findnew_thread failed\n");
463 cpus = cpu_map__new(NULL);
465 pr_debug("cpu_map__new failed\n");
472 evlist = perf_evlist__new();
474 pr_debug("perf_evlist__new failed\n");
478 perf_evlist__set_maps(evlist, cpus, threads);
484 pr_debug("Parsing event '%s'\n", str);
485 ret = parse_events(evlist, str);
487 pr_debug("parse_events failed\n");
491 perf_evlist__config(evlist, &opts);
493 evsel = perf_evlist__first(evlist);
495 evsel->attr.comm = 1;
496 evsel->attr.disabled = 1;
497 evsel->attr.enable_on_exec = 0;
499 ret = perf_evlist__open(evlist);
503 perf_evlist__set_maps(evlist, NULL, NULL);
504 perf_evlist__delete(evlist);
508 pr_debug("perf_evlist__open failed\n");
514 ret = perf_evlist__mmap(evlist, UINT_MAX, false);
516 pr_debug("perf_evlist__mmap failed\n");
520 perf_evlist__enable(evlist);
524 perf_evlist__disable(evlist);
526 ret = process_events(machine, evlist, &state);
530 if (!have_vmlinux && !have_kcore && !try_kcore)
531 err = TEST_CODE_READING_NO_KERNEL_OBJ;
532 else if (!have_vmlinux && !try_kcore)
533 err = TEST_CODE_READING_NO_VMLINUX;
534 else if (excl_kernel)
535 err = TEST_CODE_READING_NO_ACCESS;
537 err = TEST_CODE_READING_OK;
540 perf_evlist__delete(evlist);
542 cpu_map__delete(cpus);
543 thread_map__delete(threads);
545 machines__destroy_kernel_maps(&machines);
546 machine__delete_threads(machine);
547 machines__exit(&machines);
552 int test__code_reading(void)
556 ret = do_test_code_reading(false);
558 ret = do_test_code_reading(true);
561 case TEST_CODE_READING_OK:
563 case TEST_CODE_READING_NO_VMLINUX:
564 fprintf(stderr, " (no vmlinux)");
566 case TEST_CODE_READING_NO_KCORE:
567 fprintf(stderr, " (no kcore)");
569 case TEST_CODE_READING_NO_ACCESS:
570 fprintf(stderr, " (no access)");
572 case TEST_CODE_READING_NO_KERNEL_OBJ:
573 fprintf(stderr, " (no kernel obj)");