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_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);
72 /* return number of successfully read bytes */
76 static int read_objdump_output(FILE *f, void *buf, size_t *len, u64 start_addr)
79 size_t line_len, off_last = 0;
82 u64 addr, last_addr = start_addr;
84 while (off_last < *len) {
85 size_t off, read_bytes, written_bytes;
86 unsigned char tmp[BUFSZ];
88 ret = getline(&line, &line_len, f);
92 pr_debug("getline failed\n");
97 /* read objdump data into temporary buffer */
98 read_bytes = read_objdump_line(line, ret, tmp, sizeof(tmp));
102 if (sscanf(line, "%"PRIx64, &addr) != 1)
104 if (addr < last_addr) {
105 pr_debug("addr going backwards, read beyond section?\n");
110 /* copy it from temporary buffer to 'buf' according
111 * to address on current objdump line */
112 off = addr - start_addr;
115 written_bytes = MIN(read_bytes, *len - off);
116 memcpy(buf + off, tmp, written_bytes);
117 off_last = off + written_bytes;
120 /* len returns number of bytes that could not be read */
128 static int read_via_objdump(const char *filename, u64 addr, void *buf,
131 char cmd[PATH_MAX * 2];
136 fmt = "%s -z -d --start-address=0x%"PRIx64" --stop-address=0x%"PRIx64" %s";
137 ret = snprintf(cmd, sizeof(cmd), fmt, "objdump", addr, addr + len,
139 if (ret <= 0 || (size_t)ret >= sizeof(cmd))
142 pr_debug("Objdump command is: %s\n", cmd);
144 /* Ignore objdump errors */
145 strcat(cmd, " 2>/dev/null");
149 pr_debug("popen failed\n");
153 ret = read_objdump_output(f, buf, &len, addr);
155 pr_debug("objdump read too few bytes\n");
165 static void dump_buf(unsigned char *buf, size_t len)
169 for (i = 0; i < len; i++) {
170 pr_debug("0x%02x ", buf[i]);
177 static int read_object_code(u64 addr, size_t len, u8 cpumode,
178 struct thread *thread, struct state *state)
180 struct addr_location al;
181 unsigned char buf1[BUFSZ];
182 unsigned char buf2[BUFSZ];
187 pr_debug("Reading object code for memory address: %#"PRIx64"\n", addr);
189 thread__find_addr_map(thread, cpumode, MAP__FUNCTION, addr, &al);
190 if (!al.map || !al.map->dso) {
191 pr_debug("thread__find_addr_map failed\n");
195 pr_debug("File is: %s\n", al.map->dso->long_name);
197 if (al.map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS &&
198 !dso__is_kcore(al.map->dso)) {
199 pr_debug("Unexpected kernel address - skipping\n");
203 pr_debug("On file address is: %#"PRIx64"\n", al.addr);
208 /* Do not go off the map */
209 if (addr + len > al.map->end)
210 len = al.map->end - addr;
212 /* Read the object code using perf */
213 ret_len = dso__data_read_offset(al.map->dso, thread->mg->machine,
215 if (ret_len != len) {
216 pr_debug("dso__data_read_offset failed\n");
221 * Converting addresses for use by objdump requires more information.
222 * map__load() does that. See map__rip_2objdump() for details.
224 if (map__load(al.map, NULL))
227 /* objdump struggles with kcore - try each map only once */
228 if (dso__is_kcore(al.map->dso)) {
231 for (d = 0; d < state->done_cnt; d++) {
232 if (state->done[d] == al.map->start) {
233 pr_debug("kcore map tested already");
234 pr_debug(" - skipping\n");
238 if (state->done_cnt >= ARRAY_SIZE(state->done)) {
239 pr_debug("Too many kcore maps - skipping\n");
242 state->done[state->done_cnt++] = al.map->start;
245 /* Read the object code using objdump */
246 objdump_addr = map__rip_2objdump(al.map, al.addr);
247 ret = read_via_objdump(al.map->dso->long_name, objdump_addr, buf2, len);
250 * The kernel maps are inaccurate - assume objdump is right in
253 if (cpumode == PERF_RECORD_MISC_KERNEL ||
254 cpumode == PERF_RECORD_MISC_GUEST_KERNEL) {
257 pr_debug("Reducing len to %zu\n", len);
258 } else if (dso__is_kcore(al.map->dso)) {
260 * objdump cannot handle very large segments
261 * that may be found in kcore.
263 pr_debug("objdump failed for kcore");
264 pr_debug(" - skipping\n");
272 pr_debug("read_via_objdump failed\n");
276 /* The results should be identical */
277 if (memcmp(buf1, buf2, len)) {
278 pr_debug("Bytes read differ from those read by objdump\n");
279 pr_debug("buf1 (dso):\n");
281 pr_debug("buf2 (objdump):\n");
285 pr_debug("Bytes read match those read by objdump\n");
290 static int process_sample_event(struct machine *machine,
291 struct perf_evlist *evlist,
292 union perf_event *event, struct state *state)
294 struct perf_sample sample;
295 struct thread *thread;
298 if (perf_evlist__parse_sample(evlist, event, &sample)) {
299 pr_debug("perf_evlist__parse_sample failed\n");
303 thread = machine__findnew_thread(machine, sample.pid, sample.tid);
305 pr_debug("machine__findnew_thread failed\n");
309 ret = read_object_code(sample.ip, READLEN, sample.cpumode, thread, state);
314 static int process_event(struct machine *machine, struct perf_evlist *evlist,
315 union perf_event *event, struct state *state)
317 if (event->header.type == PERF_RECORD_SAMPLE)
318 return process_sample_event(machine, evlist, event, state);
320 if (event->header.type == PERF_RECORD_THROTTLE ||
321 event->header.type == PERF_RECORD_UNTHROTTLE)
324 if (event->header.type < PERF_RECORD_MAX) {
327 ret = machine__process_event(machine, event, NULL);
329 pr_debug("machine__process_event failed, event type %u\n",
337 static int process_events(struct machine *machine, struct perf_evlist *evlist,
340 union perf_event *event;
343 for (i = 0; i < evlist->nr_mmaps; i++) {
344 while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
345 ret = process_event(machine, evlist, event, state);
346 perf_evlist__mmap_consume(evlist, i);
354 static int comp(const void *a, const void *b)
356 return *(int *)a - *(int *)b;
359 static void do_sort_something(void)
363 for (i = 0; i < (int)ARRAY_SIZE(buf); i++)
364 buf[i] = ARRAY_SIZE(buf) - i - 1;
366 qsort(buf, ARRAY_SIZE(buf), sizeof(int), comp);
368 for (i = 0; i < (int)ARRAY_SIZE(buf); i++) {
370 pr_debug("qsort failed\n");
376 static void sort_something(void)
380 for (i = 0; i < 10; i++)
384 static void syscall_something(void)
389 for (i = 0; i < 1000; i++) {
390 if (pipe(pipefd) < 0) {
391 pr_debug("pipe failed\n");
399 static void fs_something(void)
401 const char *test_file_name = "temp-perf-code-reading-test-file--";
405 for (i = 0; i < 1000; i++) {
406 f = fopen(test_file_name, "w+");
409 unlink(test_file_name);
414 static void do_something(void)
424 TEST_CODE_READING_OK,
425 TEST_CODE_READING_NO_VMLINUX,
426 TEST_CODE_READING_NO_KCORE,
427 TEST_CODE_READING_NO_ACCESS,
428 TEST_CODE_READING_NO_KERNEL_OBJ,
431 static int do_test_code_reading(bool try_kcore)
433 struct machine *machine;
434 struct thread *thread;
435 struct record_opts opts = {
436 .mmap_pages = UINT_MAX,
437 .user_freq = UINT_MAX,
438 .user_interval = ULLONG_MAX,
444 struct state state = {
447 struct thread_map *threads = NULL;
448 struct cpu_map *cpus = NULL;
449 struct perf_evlist *evlist = NULL;
450 struct perf_evsel *evsel = NULL;
454 bool have_vmlinux, have_kcore, excl_kernel = false;
458 machine = machine__new_host();
460 ret = machine__create_kernel_maps(machine);
462 pr_debug("machine__create_kernel_maps failed\n");
466 /* Force the use of kallsyms instead of vmlinux to try kcore */
468 symbol_conf.kallsyms_name = "/proc/kallsyms";
470 /* Load kernel map */
471 map = machine__kernel_map(machine);
472 ret = map__load(map, NULL);
474 pr_debug("map__load failed\n");
477 have_vmlinux = dso__is_vmlinux(map->dso);
478 have_kcore = dso__is_kcore(map->dso);
480 /* 2nd time through we just try kcore */
481 if (try_kcore && !have_kcore)
482 return TEST_CODE_READING_NO_KCORE;
484 /* No point getting kernel events if there is no kernel object */
485 if (!have_vmlinux && !have_kcore)
488 threads = thread_map__new_by_tid(pid);
490 pr_debug("thread_map__new_by_tid failed\n");
494 ret = perf_event__synthesize_thread_map(NULL, threads,
495 perf_event__process, machine, false, 500);
497 pr_debug("perf_event__synthesize_thread_map failed\n");
501 thread = machine__findnew_thread(machine, pid, pid);
503 pr_debug("machine__findnew_thread failed\n");
507 cpus = cpu_map__new(NULL);
509 pr_debug("cpu_map__new failed\n");
516 evlist = perf_evlist__new();
518 pr_debug("perf_evlist__new failed\n");
522 perf_evlist__set_maps(evlist, cpus, threads);
528 pr_debug("Parsing event '%s'\n", str);
529 ret = parse_events(evlist, str, NULL);
531 pr_debug("parse_events failed\n");
535 perf_evlist__config(evlist, &opts, NULL);
537 evsel = perf_evlist__first(evlist);
539 evsel->attr.comm = 1;
540 evsel->attr.disabled = 1;
541 evsel->attr.enable_on_exec = 0;
543 ret = perf_evlist__open(evlist);
548 * Both cpus and threads are now owned by evlist
549 * and will be freed by following perf_evlist__set_maps
550 * call. Getting refference to keep them alive.
553 thread_map__get(threads);
554 perf_evlist__set_maps(evlist, NULL, NULL);
555 perf_evlist__delete(evlist);
562 perf_evlist__strerror_open(evlist, errno, errbuf, sizeof(errbuf));
563 pr_debug("perf_evlist__open() failed!\n%s\n", errbuf);
571 ret = perf_evlist__mmap(evlist, UINT_MAX, false);
573 pr_debug("perf_evlist__mmap failed\n");
577 perf_evlist__enable(evlist);
581 perf_evlist__disable(evlist);
583 ret = process_events(machine, evlist, &state);
587 if (!have_vmlinux && !have_kcore && !try_kcore)
588 err = TEST_CODE_READING_NO_KERNEL_OBJ;
589 else if (!have_vmlinux && !try_kcore)
590 err = TEST_CODE_READING_NO_VMLINUX;
591 else if (excl_kernel)
592 err = TEST_CODE_READING_NO_ACCESS;
594 err = TEST_CODE_READING_OK;
600 perf_evlist__delete(evlist);
603 thread_map__put(threads);
605 machine__delete_threads(machine);
606 machine__delete(machine);
611 int test__code_reading(int subtest __maybe_unused)
615 ret = do_test_code_reading(false);
617 ret = do_test_code_reading(true);
620 case TEST_CODE_READING_OK:
622 case TEST_CODE_READING_NO_VMLINUX:
623 pr_debug("no vmlinux\n");
625 case TEST_CODE_READING_NO_KCORE:
626 pr_debug("no kcore\n");
628 case TEST_CODE_READING_NO_ACCESS:
629 pr_debug("no access\n");
631 case TEST_CODE_READING_NO_KERNEL_OBJ:
632 pr_debug("no kernel obj\n");