1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include "util.h" |
3 | #include "debug.h" |
4 | #include "event.h" |
5 | #include <api/fs/fs.h> |
6 | #include <sys/stat.h> |
7 | #include <sys/utsname.h> |
8 | #include <dirent.h> |
9 | #include <fcntl.h> |
10 | #include <inttypes.h> |
11 | #include <signal.h> |
12 | #include <stdio.h> |
13 | #include <stdlib.h> |
14 | #include <string.h> |
15 | #include <errno.h> |
16 | #include <limits.h> |
17 | #include <linux/capability.h> |
18 | #include <linux/kernel.h> |
19 | #include <linux/log2.h> |
20 | #include <linux/time64.h> |
21 | #include <linux/overflow.h> |
22 | #include <unistd.h> |
23 | #include "cap.h" |
24 | #include "strlist.h" |
25 | #include "string2.h" |
26 | |
27 | /* |
28 | * XXX We need to find a better place for these things... |
29 | */ |
30 | |
31 | const char *input_name; |
32 | |
33 | bool perf_singlethreaded = true; |
34 | |
35 | void perf_set_singlethreaded(void) |
36 | { |
37 | perf_singlethreaded = true; |
38 | } |
39 | |
40 | void perf_set_multithreaded(void) |
41 | { |
42 | perf_singlethreaded = false; |
43 | } |
44 | |
45 | int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH; |
46 | int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK; |
47 | |
48 | int sysctl__max_stack(void) |
49 | { |
50 | int value; |
51 | |
52 | if (sysctl__read_int("kernel/perf_event_max_stack" , &value) == 0) |
53 | sysctl_perf_event_max_stack = value; |
54 | |
55 | if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack" , &value) == 0) |
56 | sysctl_perf_event_max_contexts_per_stack = value; |
57 | |
58 | return sysctl_perf_event_max_stack; |
59 | } |
60 | |
61 | bool sysctl__nmi_watchdog_enabled(void) |
62 | { |
63 | static bool cached; |
64 | static bool nmi_watchdog; |
65 | int value; |
66 | |
67 | if (cached) |
68 | return nmi_watchdog; |
69 | |
70 | if (sysctl__read_int("kernel/nmi_watchdog" , &value) < 0) |
71 | return false; |
72 | |
73 | nmi_watchdog = (value > 0) ? true : false; |
74 | cached = true; |
75 | |
76 | return nmi_watchdog; |
77 | } |
78 | |
79 | bool test_attr__enabled; |
80 | |
81 | bool perf_host = true; |
82 | bool perf_guest = false; |
83 | |
84 | void event_attr_init(struct perf_event_attr *attr) |
85 | { |
86 | if (!perf_host) |
87 | attr->exclude_host = 1; |
88 | if (!perf_guest) |
89 | attr->exclude_guest = 1; |
90 | /* to capture ABI version */ |
91 | attr->size = sizeof(*attr); |
92 | } |
93 | |
94 | int mkdir_p(char *path, mode_t mode) |
95 | { |
96 | struct stat st; |
97 | int err; |
98 | char *d = path; |
99 | |
100 | if (*d != '/') |
101 | return -1; |
102 | |
103 | if (stat(path, &st) == 0) |
104 | return 0; |
105 | |
106 | while (*++d == '/'); |
107 | |
108 | while ((d = strchr(d, '/'))) { |
109 | *d = '\0'; |
110 | err = stat(path, &st) && mkdir(path, mode); |
111 | *d++ = '/'; |
112 | if (err) |
113 | return -1; |
114 | while (*d == '/') |
115 | ++d; |
116 | } |
117 | return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0; |
118 | } |
119 | |
120 | static bool match_pat(char *file, const char **pat) |
121 | { |
122 | int i = 0; |
123 | |
124 | if (!pat) |
125 | return true; |
126 | |
127 | while (pat[i]) { |
128 | if (strglobmatch(str: file, pat: pat[i])) |
129 | return true; |
130 | |
131 | i++; |
132 | } |
133 | |
134 | return false; |
135 | } |
136 | |
137 | /* |
138 | * The depth specify how deep the removal will go. |
139 | * 0 - will remove only files under the 'path' directory |
140 | * 1 .. x - will dive in x-level deep under the 'path' directory |
141 | * |
142 | * If specified the pat is array of string patterns ended with NULL, |
143 | * which are checked upon every file/directory found. Only matching |
144 | * ones are removed. |
145 | * |
146 | * The function returns: |
147 | * 0 on success |
148 | * -1 on removal failure with errno set |
149 | * -2 on pattern failure |
150 | */ |
151 | static int rm_rf_depth_pat(const char *path, int depth, const char **pat) |
152 | { |
153 | DIR *dir; |
154 | int ret; |
155 | struct dirent *d; |
156 | char namebuf[PATH_MAX]; |
157 | struct stat statbuf; |
158 | |
159 | /* Do not fail if there's no file. */ |
160 | ret = lstat(path, &statbuf); |
161 | if (ret) |
162 | return 0; |
163 | |
164 | /* Try to remove any file we get. */ |
165 | if (!(statbuf.st_mode & S_IFDIR)) |
166 | return unlink(path); |
167 | |
168 | /* We have directory in path. */ |
169 | dir = opendir(path); |
170 | if (dir == NULL) |
171 | return -1; |
172 | |
173 | while ((d = readdir(dir)) != NULL && !ret) { |
174 | |
175 | if (!strcmp(d->d_name, "." ) || !strcmp(d->d_name, ".." )) |
176 | continue; |
177 | |
178 | if (!match_pat(file: d->d_name, pat)) { |
179 | ret = -2; |
180 | break; |
181 | } |
182 | |
183 | scnprintf(buf: namebuf, size: sizeof(namebuf), fmt: "%s/%s" , |
184 | path, d->d_name); |
185 | |
186 | /* We have to check symbolic link itself */ |
187 | ret = lstat(namebuf, &statbuf); |
188 | if (ret < 0) { |
189 | pr_debug("stat failed: %s\n" , namebuf); |
190 | break; |
191 | } |
192 | |
193 | if (S_ISDIR(statbuf.st_mode)) |
194 | ret = depth ? rm_rf_depth_pat(path: namebuf, depth: depth - 1, pat) : 0; |
195 | else |
196 | ret = unlink(namebuf); |
197 | } |
198 | closedir(dir); |
199 | |
200 | if (ret < 0) |
201 | return ret; |
202 | |
203 | return rmdir(path); |
204 | } |
205 | |
206 | static int rm_rf_a_kcore_dir(const char *path, const char *name) |
207 | { |
208 | char kcore_dir_path[PATH_MAX]; |
209 | const char *pat[] = { |
210 | "kcore" , |
211 | "kallsyms" , |
212 | "modules" , |
213 | NULL, |
214 | }; |
215 | |
216 | snprintf(buf: kcore_dir_path, size: sizeof(kcore_dir_path), fmt: "%s/%s" , path, name); |
217 | |
218 | return rm_rf_depth_pat(path: kcore_dir_path, depth: 0, pat); |
219 | } |
220 | |
221 | static bool kcore_dir_filter(const char *name __maybe_unused, struct dirent *d) |
222 | { |
223 | const char *pat[] = { |
224 | "kcore_dir" , |
225 | "kcore_dir__[1-9]*" , |
226 | NULL, |
227 | }; |
228 | |
229 | return match_pat(file: d->d_name, pat); |
230 | } |
231 | |
232 | static int rm_rf_kcore_dir(const char *path) |
233 | { |
234 | struct strlist *kcore_dirs; |
235 | struct str_node *nd; |
236 | int ret; |
237 | |
238 | kcore_dirs = lsdir(name: path, filter: kcore_dir_filter); |
239 | |
240 | if (!kcore_dirs) |
241 | return 0; |
242 | |
243 | strlist__for_each_entry(nd, kcore_dirs) { |
244 | ret = rm_rf_a_kcore_dir(path, name: nd->s); |
245 | if (ret) |
246 | return ret; |
247 | } |
248 | |
249 | strlist__delete(slist: kcore_dirs); |
250 | |
251 | return 0; |
252 | } |
253 | |
254 | int rm_rf_perf_data(const char *path) |
255 | { |
256 | const char *pat[] = { |
257 | "data" , |
258 | "data.*" , |
259 | NULL, |
260 | }; |
261 | |
262 | rm_rf_kcore_dir(path); |
263 | |
264 | return rm_rf_depth_pat(path, depth: 0, pat); |
265 | } |
266 | |
267 | int rm_rf(const char *path) |
268 | { |
269 | return rm_rf_depth_pat(path, INT_MAX, NULL); |
270 | } |
271 | |
272 | /* A filter which removes dot files */ |
273 | bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d) |
274 | { |
275 | return d->d_name[0] != '.'; |
276 | } |
277 | |
278 | /* lsdir reads a directory and store it in strlist */ |
279 | struct strlist *lsdir(const char *name, |
280 | bool (*filter)(const char *, struct dirent *)) |
281 | { |
282 | struct strlist *list = NULL; |
283 | DIR *dir; |
284 | struct dirent *d; |
285 | |
286 | dir = opendir(name); |
287 | if (!dir) |
288 | return NULL; |
289 | |
290 | list = strlist__new(NULL, NULL); |
291 | if (!list) { |
292 | errno = ENOMEM; |
293 | goto out; |
294 | } |
295 | |
296 | while ((d = readdir(dir)) != NULL) { |
297 | if (!filter || filter(name, d)) |
298 | strlist__add(slist: list, str: d->d_name); |
299 | } |
300 | |
301 | out: |
302 | closedir(dir); |
303 | return list; |
304 | } |
305 | |
306 | size_t hex_width(u64 v) |
307 | { |
308 | size_t n = 1; |
309 | |
310 | while ((v >>= 4)) |
311 | ++n; |
312 | |
313 | return n; |
314 | } |
315 | |
316 | int perf_event_paranoid(void) |
317 | { |
318 | int value; |
319 | |
320 | if (sysctl__read_int("kernel/perf_event_paranoid" , &value)) |
321 | return INT_MAX; |
322 | |
323 | return value; |
324 | } |
325 | |
326 | bool perf_event_paranoid_check(int max_level) |
327 | { |
328 | return perf_cap__capable(CAP_SYS_ADMIN) || |
329 | perf_cap__capable(CAP_PERFMON) || |
330 | perf_event_paranoid() <= max_level; |
331 | } |
332 | |
333 | static int |
334 | fetch_ubuntu_kernel_version(unsigned int *puint) |
335 | { |
336 | ssize_t len; |
337 | size_t line_len = 0; |
338 | char *ptr, *line = NULL; |
339 | int version, patchlevel, sublevel, err; |
340 | FILE *vsig; |
341 | |
342 | if (!puint) |
343 | return 0; |
344 | |
345 | vsig = fopen("/proc/version_signature" , "r" ); |
346 | if (!vsig) { |
347 | pr_debug("Open /proc/version_signature failed: %s\n" , |
348 | strerror(errno)); |
349 | return -1; |
350 | } |
351 | |
352 | len = getline(&line, &line_len, vsig); |
353 | fclose(vsig); |
354 | err = -1; |
355 | if (len <= 0) { |
356 | pr_debug("Reading from /proc/version_signature failed: %s\n" , |
357 | strerror(errno)); |
358 | goto errout; |
359 | } |
360 | |
361 | ptr = strrchr(line, ' '); |
362 | if (!ptr) { |
363 | pr_debug("Parsing /proc/version_signature failed: %s\n" , line); |
364 | goto errout; |
365 | } |
366 | |
367 | err = sscanf(ptr + 1, "%d.%d.%d" , |
368 | &version, &patchlevel, &sublevel); |
369 | if (err != 3) { |
370 | pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n" , |
371 | line); |
372 | goto errout; |
373 | } |
374 | |
375 | *puint = (version << 16) + (patchlevel << 8) + sublevel; |
376 | err = 0; |
377 | errout: |
378 | free(line); |
379 | return err; |
380 | } |
381 | |
382 | int |
383 | fetch_kernel_version(unsigned int *puint, char *str, |
384 | size_t str_size) |
385 | { |
386 | struct utsname utsname; |
387 | int version, patchlevel, sublevel, err; |
388 | bool int_ver_ready = false; |
389 | |
390 | if (access("/proc/version_signature" , R_OK) == 0) |
391 | if (!fetch_ubuntu_kernel_version(puint)) |
392 | int_ver_ready = true; |
393 | |
394 | if (uname(&utsname)) |
395 | return -1; |
396 | |
397 | if (str && str_size) { |
398 | strncpy(str, utsname.release, str_size); |
399 | str[str_size - 1] = '\0'; |
400 | } |
401 | |
402 | if (!puint || int_ver_ready) |
403 | return 0; |
404 | |
405 | err = sscanf(utsname.release, "%d.%d.%d" , |
406 | &version, &patchlevel, &sublevel); |
407 | |
408 | if (err != 3) { |
409 | pr_debug("Unable to get kernel version from uname '%s'\n" , |
410 | utsname.release); |
411 | return -1; |
412 | } |
413 | |
414 | *puint = (version << 16) + (patchlevel << 8) + sublevel; |
415 | return 0; |
416 | } |
417 | |
418 | int perf_tip(char **strp, const char *dirpath) |
419 | { |
420 | struct strlist *tips; |
421 | struct str_node *node; |
422 | struct strlist_config conf = { |
423 | .dirname = dirpath, |
424 | .file_only = true, |
425 | }; |
426 | int ret = 0; |
427 | |
428 | *strp = NULL; |
429 | tips = strlist__new(slist: "tips.txt" , config: &conf); |
430 | if (tips == NULL) |
431 | return -errno; |
432 | |
433 | if (strlist__nr_entries(slist: tips) == 0) |
434 | goto out; |
435 | |
436 | node = strlist__entry(slist: tips, idx: random() % strlist__nr_entries(slist: tips)); |
437 | if (asprintf(strp, "Tip: %s" , node->s) < 0) |
438 | ret = -ENOMEM; |
439 | |
440 | out: |
441 | strlist__delete(slist: tips); |
442 | |
443 | return ret; |
444 | } |
445 | |
446 | char *perf_exe(char *buf, int len) |
447 | { |
448 | int n = readlink("/proc/self/exe" , buf, len); |
449 | if (n > 0) { |
450 | buf[n] = 0; |
451 | return buf; |
452 | } |
453 | return strcpy(p: buf, q: "perf" ); |
454 | } |
455 | |
456 | void perf_debuginfod_setup(struct perf_debuginfod *di) |
457 | { |
458 | /* |
459 | * By default '!di->set' we clear DEBUGINFOD_URLS, so debuginfod |
460 | * processing is not triggered, otherwise we set it to 'di->urls' |
461 | * value. If 'di->urls' is "system" we keep DEBUGINFOD_URLS value. |
462 | */ |
463 | if (!di->set) |
464 | setenv("DEBUGINFOD_URLS" , "" , 1); |
465 | else if (di->urls && strcmp(di->urls, "system" )) |
466 | setenv("DEBUGINFOD_URLS" , di->urls, 1); |
467 | |
468 | pr_debug("DEBUGINFOD_URLS=%s\n" , getenv("DEBUGINFOD_URLS" )); |
469 | |
470 | #ifndef HAVE_DEBUGINFOD_SUPPORT |
471 | if (di->set) |
472 | pr_warning("WARNING: debuginfod support requested, but perf is not built with it\n" ); |
473 | #endif |
474 | } |
475 | |
476 | /* |
477 | * Return a new filename prepended with task's root directory if it's in |
478 | * a chroot. Callers should free the returned string. |
479 | */ |
480 | char *filename_with_chroot(int pid, const char *filename) |
481 | { |
482 | char buf[PATH_MAX]; |
483 | char proc_root[32]; |
484 | char *new_name = NULL; |
485 | int ret; |
486 | |
487 | scnprintf(buf: proc_root, size: sizeof(proc_root), fmt: "/proc/%d/root" , pid); |
488 | ret = readlink(proc_root, buf, sizeof(buf) - 1); |
489 | if (ret <= 0) |
490 | return NULL; |
491 | |
492 | /* readlink(2) does not append a null byte to buf */ |
493 | buf[ret] = '\0'; |
494 | |
495 | if (!strcmp(buf, "/" )) |
496 | return NULL; |
497 | |
498 | if (strstr(buf, "(deleted)" )) |
499 | return NULL; |
500 | |
501 | if (asprintf(&new_name, "%s/%s" , buf, filename) < 0) |
502 | return NULL; |
503 | |
504 | return new_name; |
505 | } |
506 | |
507 | /* |
508 | * Reallocate an array *arr of size *arr_sz so that it is big enough to contain |
509 | * x elements of size msz, initializing new entries to *init_val or zero if |
510 | * init_val is NULL |
511 | */ |
512 | int do_realloc_array_as_needed(void **arr, size_t *arr_sz, size_t x, size_t msz, const void *init_val) |
513 | { |
514 | size_t new_sz = *arr_sz; |
515 | void *new_arr; |
516 | size_t i; |
517 | |
518 | if (!new_sz) |
519 | new_sz = msz >= 64 ? 1 : roundup(64, msz); /* Start with at least 64 bytes */ |
520 | while (x >= new_sz) { |
521 | if (check_mul_overflow(new_sz, (size_t)2, &new_sz)) |
522 | return -ENOMEM; |
523 | } |
524 | if (new_sz == *arr_sz) |
525 | return 0; |
526 | new_arr = calloc(new_sz, msz); |
527 | if (!new_arr) |
528 | return -ENOMEM; |
529 | if (*arr_sz) |
530 | memcpy(new_arr, *arr, *arr_sz * msz); |
531 | if (init_val) { |
532 | for (i = *arr_sz; i < new_sz; i++) |
533 | memcpy(new_arr + (i * msz), init_val, msz); |
534 | } |
535 | *arr = new_arr; |
536 | *arr_sz = new_sz; |
537 | return 0; |
538 | } |
539 | |
540 | #ifndef HAVE_SCHED_GETCPU_SUPPORT |
541 | int sched_getcpu(void) |
542 | { |
543 | #ifdef __NR_getcpu |
544 | unsigned int cpu; |
545 | int err = syscall(__NR_getcpu, &cpu, NULL, NULL); |
546 | |
547 | if (!err) |
548 | return cpu; |
549 | #else |
550 | errno = ENOSYS; |
551 | #endif |
552 | return -1; |
553 | } |
554 | #endif |
555 | |
556 | #ifndef HAVE_SCANDIRAT_SUPPORT |
557 | int scandirat(int dirfd, const char *dirp, |
558 | struct dirent ***namelist, |
559 | int (*filter)(const struct dirent *), |
560 | int (*compar)(const struct dirent **, const struct dirent **)) |
561 | { |
562 | char path[PATH_MAX]; |
563 | int err, fd = openat(dirfd, dirp, O_PATH); |
564 | |
565 | if (fd < 0) |
566 | return fd; |
567 | |
568 | snprintf(buf: path, size: sizeof(path), fmt: "/proc/%d/fd/%d" , getpid(), fd); |
569 | err = scandir(path, namelist, filter, compar); |
570 | close(fd); |
571 | return err; |
572 | } |
573 | #endif |
574 | |