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;
253 if (perf_evlist__parse_sample(evlist, event, &sample)) {
254 pr_debug("perf_evlist__parse_sample failed\n");
258 thread = machine__findnew_thread(machine, sample.pid, sample.tid);
260 pr_debug("machine__findnew_thread failed\n");
264 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
266 ret = read_object_code(sample.ip, READLEN, cpumode, thread, state);
271 static int process_event(struct machine *machine, struct perf_evlist *evlist,
272 union perf_event *event, struct state *state)
274 if (event->header.type == PERF_RECORD_SAMPLE)
275 return process_sample_event(machine, evlist, event, state);
277 if (event->header.type == PERF_RECORD_THROTTLE ||
278 event->header.type == PERF_RECORD_UNTHROTTLE)
281 if (event->header.type < PERF_RECORD_MAX) {
284 ret = machine__process_event(machine, event, NULL);
286 pr_debug("machine__process_event failed, event type %u\n",
294 static int process_events(struct machine *machine, struct perf_evlist *evlist,
297 union perf_event *event;
300 for (i = 0; i < evlist->nr_mmaps; i++) {
301 while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
302 ret = process_event(machine, evlist, event, state);
303 perf_evlist__mmap_consume(evlist, i);
311 static int comp(const void *a, const void *b)
313 return *(int *)a - *(int *)b;
316 static void do_sort_something(void)
320 for (i = 0; i < (int)ARRAY_SIZE(buf); i++)
321 buf[i] = ARRAY_SIZE(buf) - i - 1;
323 qsort(buf, ARRAY_SIZE(buf), sizeof(int), comp);
325 for (i = 0; i < (int)ARRAY_SIZE(buf); i++) {
327 pr_debug("qsort failed\n");
333 static void sort_something(void)
337 for (i = 0; i < 10; i++)
341 static void syscall_something(void)
346 for (i = 0; i < 1000; i++) {
347 if (pipe(pipefd) < 0) {
348 pr_debug("pipe failed\n");
356 static void fs_something(void)
358 const char *test_file_name = "temp-perf-code-reading-test-file--";
362 for (i = 0; i < 1000; i++) {
363 f = fopen(test_file_name, "w+");
366 unlink(test_file_name);
371 static void do_something(void)
381 TEST_CODE_READING_OK,
382 TEST_CODE_READING_NO_VMLINUX,
383 TEST_CODE_READING_NO_KCORE,
384 TEST_CODE_READING_NO_ACCESS,
385 TEST_CODE_READING_NO_KERNEL_OBJ,
388 static int do_test_code_reading(bool try_kcore)
390 struct machines machines;
391 struct machine *machine;
392 struct thread *thread;
393 struct record_opts opts = {
394 .mmap_pages = UINT_MAX,
395 .user_freq = UINT_MAX,
396 .user_interval = ULLONG_MAX,
402 struct state state = {
405 struct thread_map *threads = NULL;
406 struct cpu_map *cpus = NULL;
407 struct perf_evlist *evlist = NULL;
408 struct perf_evsel *evsel = NULL;
412 bool have_vmlinux, have_kcore, excl_kernel = false;
416 machines__init(&machines);
417 machine = &machines.host;
419 ret = machine__create_kernel_maps(machine);
421 pr_debug("machine__create_kernel_maps failed\n");
425 /* Force the use of kallsyms instead of vmlinux to try kcore */
427 symbol_conf.kallsyms_name = "/proc/kallsyms";
429 /* Load kernel map */
430 map = machine->vmlinux_maps[MAP__FUNCTION];
431 ret = map__load(map, NULL);
433 pr_debug("map__load failed\n");
436 have_vmlinux = dso__is_vmlinux(map->dso);
437 have_kcore = dso__is_kcore(map->dso);
439 /* 2nd time through we just try kcore */
440 if (try_kcore && !have_kcore)
441 return TEST_CODE_READING_NO_KCORE;
443 /* No point getting kernel events if there is no kernel object */
444 if (!have_vmlinux && !have_kcore)
447 threads = thread_map__new_by_tid(pid);
449 pr_debug("thread_map__new_by_tid failed\n");
453 ret = perf_event__synthesize_thread_map(NULL, threads,
454 perf_event__process, machine, false, 500);
456 pr_debug("perf_event__synthesize_thread_map failed\n");
460 thread = machine__findnew_thread(machine, pid, pid);
462 pr_debug("machine__findnew_thread failed\n");
466 cpus = cpu_map__new(NULL);
468 pr_debug("cpu_map__new failed\n");
475 evlist = perf_evlist__new();
477 pr_debug("perf_evlist__new failed\n");
481 perf_evlist__set_maps(evlist, cpus, threads);
487 pr_debug("Parsing event '%s'\n", str);
488 ret = parse_events(evlist, str, NULL);
490 pr_debug("parse_events failed\n");
494 perf_evlist__config(evlist, &opts);
496 evsel = perf_evlist__first(evlist);
498 evsel->attr.comm = 1;
499 evsel->attr.disabled = 1;
500 evsel->attr.enable_on_exec = 0;
502 ret = perf_evlist__open(evlist);
506 perf_evlist__set_maps(evlist, NULL, NULL);
507 perf_evlist__delete(evlist);
511 pr_debug("perf_evlist__open failed\n");
517 ret = perf_evlist__mmap(evlist, UINT_MAX, false);
519 pr_debug("perf_evlist__mmap failed\n");
523 perf_evlist__enable(evlist);
527 perf_evlist__disable(evlist);
529 ret = process_events(machine, evlist, &state);
533 if (!have_vmlinux && !have_kcore && !try_kcore)
534 err = TEST_CODE_READING_NO_KERNEL_OBJ;
535 else if (!have_vmlinux && !try_kcore)
536 err = TEST_CODE_READING_NO_VMLINUX;
537 else if (excl_kernel)
538 err = TEST_CODE_READING_NO_ACCESS;
540 err = TEST_CODE_READING_OK;
546 perf_evlist__delete(evlist);
549 thread_map__put(threads);
551 machines__destroy_kernel_maps(&machines);
552 machine__delete_threads(machine);
553 machines__exit(&machines);
558 int test__code_reading(void)
562 ret = do_test_code_reading(false);
564 ret = do_test_code_reading(true);
567 case TEST_CODE_READING_OK:
569 case TEST_CODE_READING_NO_VMLINUX:
570 fprintf(stderr, " (no vmlinux)");
572 case TEST_CODE_READING_NO_KCORE:
573 fprintf(stderr, " (no kcore)");
575 case TEST_CODE_READING_NO_ACCESS:
576 fprintf(stderr, " (no access)");
578 case TEST_CODE_READING_NO_KERNEL_OBJ:
579 fprintf(stderr, " (no kernel obj)");