Loading...
1#include "../perf.h"
2#include "util.h"
3#include <api/fs/fs.h>
4#include <sys/mman.h>
5#ifdef HAVE_BACKTRACE_SUPPORT
6#include <execinfo.h>
7#endif
8#include <stdio.h>
9#include <stdlib.h>
10#include <string.h>
11#include <errno.h>
12#include <limits.h>
13#include <byteswap.h>
14#include <linux/kernel.h>
15
16/*
17 * XXX We need to find a better place for these things...
18 */
19unsigned int page_size;
20
21bool test_attr__enabled;
22
23bool perf_host = true;
24bool perf_guest = false;
25
26char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events";
27
28void event_attr_init(struct perf_event_attr *attr)
29{
30 if (!perf_host)
31 attr->exclude_host = 1;
32 if (!perf_guest)
33 attr->exclude_guest = 1;
34 /* to capture ABI version */
35 attr->size = sizeof(*attr);
36}
37
38int mkdir_p(char *path, mode_t mode)
39{
40 struct stat st;
41 int err;
42 char *d = path;
43
44 if (*d != '/')
45 return -1;
46
47 if (stat(path, &st) == 0)
48 return 0;
49
50 while (*++d == '/');
51
52 while ((d = strchr(d, '/'))) {
53 *d = '\0';
54 err = stat(path, &st) && mkdir(path, mode);
55 *d++ = '/';
56 if (err)
57 return -1;
58 while (*d == '/')
59 ++d;
60 }
61 return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
62}
63
64static int slow_copyfile(const char *from, const char *to, mode_t mode)
65{
66 int err = -1;
67 char *line = NULL;
68 size_t n;
69 FILE *from_fp = fopen(from, "r"), *to_fp;
70 mode_t old_umask;
71
72 if (from_fp == NULL)
73 goto out;
74
75 old_umask = umask(mode ^ 0777);
76 to_fp = fopen(to, "w");
77 umask(old_umask);
78 if (to_fp == NULL)
79 goto out_fclose_from;
80
81 while (getline(&line, &n, from_fp) > 0)
82 if (fputs(line, to_fp) == EOF)
83 goto out_fclose_to;
84 err = 0;
85out_fclose_to:
86 fclose(to_fp);
87 free(line);
88out_fclose_from:
89 fclose(from_fp);
90out:
91 return err;
92}
93
94int copyfile_mode(const char *from, const char *to, mode_t mode)
95{
96 int fromfd, tofd;
97 struct stat st;
98 void *addr;
99 int err = -1;
100
101 if (stat(from, &st))
102 goto out;
103
104 if (st.st_size == 0) /* /proc? do it slowly... */
105 return slow_copyfile(from, to, mode);
106
107 fromfd = open(from, O_RDONLY);
108 if (fromfd < 0)
109 goto out;
110
111 tofd = creat(to, mode);
112 if (tofd < 0)
113 goto out_close_from;
114
115 addr = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fromfd, 0);
116 if (addr == MAP_FAILED)
117 goto out_close_to;
118
119 if (write(tofd, addr, st.st_size) == st.st_size)
120 err = 0;
121
122 munmap(addr, st.st_size);
123out_close_to:
124 close(tofd);
125 if (err)
126 unlink(to);
127out_close_from:
128 close(fromfd);
129out:
130 return err;
131}
132
133int copyfile(const char *from, const char *to)
134{
135 return copyfile_mode(from, to, 0755);
136}
137
138unsigned long convert_unit(unsigned long value, char *unit)
139{
140 *unit = ' ';
141
142 if (value > 1000) {
143 value /= 1000;
144 *unit = 'K';
145 }
146
147 if (value > 1000) {
148 value /= 1000;
149 *unit = 'M';
150 }
151
152 if (value > 1000) {
153 value /= 1000;
154 *unit = 'G';
155 }
156
157 return value;
158}
159
160static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
161{
162 void *buf_start = buf;
163 size_t left = n;
164
165 while (left) {
166 ssize_t ret = is_read ? read(fd, buf, left) :
167 write(fd, buf, left);
168
169 if (ret <= 0)
170 return ret;
171
172 left -= ret;
173 buf += ret;
174 }
175
176 BUG_ON((size_t)(buf - buf_start) != n);
177 return n;
178}
179
180/*
181 * Read exactly 'n' bytes or return an error.
182 */
183ssize_t readn(int fd, void *buf, size_t n)
184{
185 return ion(true, fd, buf, n);
186}
187
188/*
189 * Write exactly 'n' bytes or return an error.
190 */
191ssize_t writen(int fd, void *buf, size_t n)
192{
193 return ion(false, fd, buf, n);
194}
195
196size_t hex_width(u64 v)
197{
198 size_t n = 1;
199
200 while ((v >>= 4))
201 ++n;
202
203 return n;
204}
205
206static int hex(char ch)
207{
208 if ((ch >= '0') && (ch <= '9'))
209 return ch - '0';
210 if ((ch >= 'a') && (ch <= 'f'))
211 return ch - 'a' + 10;
212 if ((ch >= 'A') && (ch <= 'F'))
213 return ch - 'A' + 10;
214 return -1;
215}
216
217/*
218 * While we find nice hex chars, build a long_val.
219 * Return number of chars processed.
220 */
221int hex2u64(const char *ptr, u64 *long_val)
222{
223 const char *p = ptr;
224 *long_val = 0;
225
226 while (*p) {
227 const int hex_val = hex(*p);
228
229 if (hex_val < 0)
230 break;
231
232 *long_val = (*long_val << 4) | hex_val;
233 p++;
234 }
235
236 return p - ptr;
237}
238
239/* Obtain a backtrace and print it to stdout. */
240#ifdef HAVE_BACKTRACE_SUPPORT
241void dump_stack(void)
242{
243 void *array[16];
244 size_t size = backtrace(array, ARRAY_SIZE(array));
245 char **strings = backtrace_symbols(array, size);
246 size_t i;
247
248 printf("Obtained %zd stack frames.\n", size);
249
250 for (i = 0; i < size; i++)
251 printf("%s\n", strings[i]);
252
253 free(strings);
254}
255#else
256void dump_stack(void) {}
257#endif
258
259void get_term_dimensions(struct winsize *ws)
260{
261 char *s = getenv("LINES");
262
263 if (s != NULL) {
264 ws->ws_row = atoi(s);
265 s = getenv("COLUMNS");
266 if (s != NULL) {
267 ws->ws_col = atoi(s);
268 if (ws->ws_row && ws->ws_col)
269 return;
270 }
271 }
272#ifdef TIOCGWINSZ
273 if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
274 ws->ws_row && ws->ws_col)
275 return;
276#endif
277 ws->ws_row = 25;
278 ws->ws_col = 80;
279}
280
281static void set_tracing_events_path(const char *mountpoint)
282{
283 snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s",
284 mountpoint, "tracing/events");
285}
286
287const char *perf_debugfs_mount(const char *mountpoint)
288{
289 const char *mnt;
290
291 mnt = debugfs_mount(mountpoint);
292 if (!mnt)
293 return NULL;
294
295 set_tracing_events_path(mnt);
296
297 return mnt;
298}
299
300void perf_debugfs_set_path(const char *mntpt)
301{
302 snprintf(debugfs_mountpoint, strlen(debugfs_mountpoint), "%s", mntpt);
303 set_tracing_events_path(mntpt);
304}
305
306static const char *find_debugfs(void)
307{
308 const char *path = perf_debugfs_mount(NULL);
309
310 if (!path)
311 fprintf(stderr, "Your kernel does not support the debugfs filesystem");
312
313 return path;
314}
315
316/*
317 * Finds the path to the debugfs/tracing
318 * Allocates the string and stores it.
319 */
320const char *find_tracing_dir(void)
321{
322 static char *tracing;
323 static int tracing_found;
324 const char *debugfs;
325
326 if (tracing_found)
327 return tracing;
328
329 debugfs = find_debugfs();
330 if (!debugfs)
331 return NULL;
332
333 tracing = malloc(strlen(debugfs) + 9);
334 if (!tracing)
335 return NULL;
336
337 sprintf(tracing, "%s/tracing", debugfs);
338
339 tracing_found = 1;
340 return tracing;
341}
342
343char *get_tracing_file(const char *name)
344{
345 const char *tracing;
346 char *file;
347
348 tracing = find_tracing_dir();
349 if (!tracing)
350 return NULL;
351
352 file = malloc(strlen(tracing) + strlen(name) + 2);
353 if (!file)
354 return NULL;
355
356 sprintf(file, "%s/%s", tracing, name);
357 return file;
358}
359
360void put_tracing_file(char *file)
361{
362 free(file);
363}
364
365int parse_nsec_time(const char *str, u64 *ptime)
366{
367 u64 time_sec, time_nsec;
368 char *end;
369
370 time_sec = strtoul(str, &end, 10);
371 if (*end != '.' && *end != '\0')
372 return -1;
373
374 if (*end == '.') {
375 int i;
376 char nsec_buf[10];
377
378 if (strlen(++end) > 9)
379 return -1;
380
381 strncpy(nsec_buf, end, 9);
382 nsec_buf[9] = '\0';
383
384 /* make it nsec precision */
385 for (i = strlen(nsec_buf); i < 9; i++)
386 nsec_buf[i] = '0';
387
388 time_nsec = strtoul(nsec_buf, &end, 10);
389 if (*end != '\0')
390 return -1;
391 } else
392 time_nsec = 0;
393
394 *ptime = time_sec * NSEC_PER_SEC + time_nsec;
395 return 0;
396}
397
398unsigned long parse_tag_value(const char *str, struct parse_tag *tags)
399{
400 struct parse_tag *i = tags;
401
402 while (i->tag) {
403 char *s;
404
405 s = strchr(str, i->tag);
406 if (s) {
407 unsigned long int value;
408 char *endptr;
409
410 value = strtoul(str, &endptr, 10);
411 if (s != endptr)
412 break;
413
414 if (value > ULONG_MAX / i->mult)
415 break;
416 value *= i->mult;
417 return value;
418 }
419 i++;
420 }
421
422 return (unsigned long) -1;
423}
424
425int filename__read_int(const char *filename, int *value)
426{
427 char line[64];
428 int fd = open(filename, O_RDONLY), err = -1;
429
430 if (fd < 0)
431 return -1;
432
433 if (read(fd, line, sizeof(line)) > 0) {
434 *value = atoi(line);
435 err = 0;
436 }
437
438 close(fd);
439 return err;
440}
441
442int filename__read_str(const char *filename, char **buf, size_t *sizep)
443{
444 size_t size = 0, alloc_size = 0;
445 void *bf = NULL, *nbf;
446 int fd, n, err = 0;
447
448 fd = open(filename, O_RDONLY);
449 if (fd < 0)
450 return -errno;
451
452 do {
453 if (size == alloc_size) {
454 alloc_size += BUFSIZ;
455 nbf = realloc(bf, alloc_size);
456 if (!nbf) {
457 err = -ENOMEM;
458 break;
459 }
460
461 bf = nbf;
462 }
463
464 n = read(fd, bf + size, alloc_size - size);
465 if (n < 0) {
466 if (size) {
467 pr_warning("read failed %d: %s\n",
468 errno, strerror(errno));
469 err = 0;
470 } else
471 err = -errno;
472
473 break;
474 }
475
476 size += n;
477 } while (n > 0);
478
479 if (!err) {
480 *sizep = size;
481 *buf = bf;
482 } else
483 free(bf);
484
485 close(fd);
486 return err;
487}
488
489const char *get_filename_for_perf_kvm(void)
490{
491 const char *filename;
492
493 if (perf_host && !perf_guest)
494 filename = strdup("perf.data.host");
495 else if (!perf_host && perf_guest)
496 filename = strdup("perf.data.guest");
497 else
498 filename = strdup("perf.data.kvm");
499
500 return filename;
501}
502
503int perf_event_paranoid(void)
504{
505 char path[PATH_MAX];
506 const char *procfs = procfs__mountpoint();
507 int value;
508
509 if (!procfs)
510 return INT_MAX;
511
512 scnprintf(path, PATH_MAX, "%s/sys/kernel/perf_event_paranoid", procfs);
513
514 if (filename__read_int(path, &value))
515 return INT_MAX;
516
517 return value;
518}
519
520void mem_bswap_32(void *src, int byte_size)
521{
522 u32 *m = src;
523 while (byte_size > 0) {
524 *m = bswap_32(*m);
525 byte_size -= sizeof(u32);
526 ++m;
527 }
528}
529
530void mem_bswap_64(void *src, int byte_size)
531{
532 u64 *m = src;
533
534 while (byte_size > 0) {
535 *m = bswap_64(*m);
536 byte_size -= sizeof(u64);
537 ++m;
538 }
539}
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 <unistd.h>
22#include "cap.h"
23#include "strlist.h"
24#include "string2.h"
25
26/*
27 * XXX We need to find a better place for these things...
28 */
29
30bool perf_singlethreaded = true;
31
32void perf_set_singlethreaded(void)
33{
34 perf_singlethreaded = true;
35}
36
37void perf_set_multithreaded(void)
38{
39 perf_singlethreaded = false;
40}
41
42int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
43int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;
44
45int sysctl__max_stack(void)
46{
47 int value;
48
49 if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
50 sysctl_perf_event_max_stack = value;
51
52 if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
53 sysctl_perf_event_max_contexts_per_stack = value;
54
55 return sysctl_perf_event_max_stack;
56}
57
58bool sysctl__nmi_watchdog_enabled(void)
59{
60 static bool cached;
61 static bool nmi_watchdog;
62 int value;
63
64 if (cached)
65 return nmi_watchdog;
66
67 if (sysctl__read_int("kernel/nmi_watchdog", &value) < 0)
68 return false;
69
70 nmi_watchdog = (value > 0) ? true : false;
71 cached = true;
72
73 return nmi_watchdog;
74}
75
76bool test_attr__enabled;
77
78bool perf_host = true;
79bool perf_guest = false;
80
81void event_attr_init(struct perf_event_attr *attr)
82{
83 if (!perf_host)
84 attr->exclude_host = 1;
85 if (!perf_guest)
86 attr->exclude_guest = 1;
87 /* to capture ABI version */
88 attr->size = sizeof(*attr);
89}
90
91int mkdir_p(char *path, mode_t mode)
92{
93 struct stat st;
94 int err;
95 char *d = path;
96
97 if (*d != '/')
98 return -1;
99
100 if (stat(path, &st) == 0)
101 return 0;
102
103 while (*++d == '/');
104
105 while ((d = strchr(d, '/'))) {
106 *d = '\0';
107 err = stat(path, &st) && mkdir(path, mode);
108 *d++ = '/';
109 if (err)
110 return -1;
111 while (*d == '/')
112 ++d;
113 }
114 return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
115}
116
117static bool match_pat(char *file, const char **pat)
118{
119 int i = 0;
120
121 if (!pat)
122 return true;
123
124 while (pat[i]) {
125 if (strglobmatch(file, pat[i]))
126 return true;
127
128 i++;
129 }
130
131 return false;
132}
133
134/*
135 * The depth specify how deep the removal will go.
136 * 0 - will remove only files under the 'path' directory
137 * 1 .. x - will dive in x-level deep under the 'path' directory
138 *
139 * If specified the pat is array of string patterns ended with NULL,
140 * which are checked upon every file/directory found. Only matching
141 * ones are removed.
142 *
143 * The function returns:
144 * 0 on success
145 * -1 on removal failure with errno set
146 * -2 on pattern failure
147 */
148static int rm_rf_depth_pat(const char *path, int depth, const char **pat)
149{
150 DIR *dir;
151 int ret;
152 struct dirent *d;
153 char namebuf[PATH_MAX];
154 struct stat statbuf;
155
156 /* Do not fail if there's no file. */
157 ret = lstat(path, &statbuf);
158 if (ret)
159 return 0;
160
161 /* Try to remove any file we get. */
162 if (!(statbuf.st_mode & S_IFDIR))
163 return unlink(path);
164
165 /* We have directory in path. */
166 dir = opendir(path);
167 if (dir == NULL)
168 return -1;
169
170 while ((d = readdir(dir)) != NULL && !ret) {
171
172 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
173 continue;
174
175 if (!match_pat(d->d_name, pat)) {
176 ret = -2;
177 break;
178 }
179
180 scnprintf(namebuf, sizeof(namebuf), "%s/%s",
181 path, d->d_name);
182
183 /* We have to check symbolic link itself */
184 ret = lstat(namebuf, &statbuf);
185 if (ret < 0) {
186 pr_debug("stat failed: %s\n", namebuf);
187 break;
188 }
189
190 if (S_ISDIR(statbuf.st_mode))
191 ret = depth ? rm_rf_depth_pat(namebuf, depth - 1, pat) : 0;
192 else
193 ret = unlink(namebuf);
194 }
195 closedir(dir);
196
197 if (ret < 0)
198 return ret;
199
200 return rmdir(path);
201}
202
203static int rm_rf_kcore_dir(const char *path)
204{
205 char kcore_dir_path[PATH_MAX];
206 const char *pat[] = {
207 "kcore",
208 "kallsyms",
209 "modules",
210 NULL,
211 };
212
213 snprintf(kcore_dir_path, sizeof(kcore_dir_path), "%s/kcore_dir", path);
214
215 return rm_rf_depth_pat(kcore_dir_path, 0, pat);
216}
217
218int rm_rf_perf_data(const char *path)
219{
220 const char *pat[] = {
221 "data",
222 "data.*",
223 NULL,
224 };
225
226 rm_rf_kcore_dir(path);
227
228 return rm_rf_depth_pat(path, 0, pat);
229}
230
231int rm_rf(const char *path)
232{
233 return rm_rf_depth_pat(path, INT_MAX, NULL);
234}
235
236/* A filter which removes dot files */
237bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d)
238{
239 return d->d_name[0] != '.';
240}
241
242/* lsdir reads a directory and store it in strlist */
243struct strlist *lsdir(const char *name,
244 bool (*filter)(const char *, struct dirent *))
245{
246 struct strlist *list = NULL;
247 DIR *dir;
248 struct dirent *d;
249
250 dir = opendir(name);
251 if (!dir)
252 return NULL;
253
254 list = strlist__new(NULL, NULL);
255 if (!list) {
256 errno = ENOMEM;
257 goto out;
258 }
259
260 while ((d = readdir(dir)) != NULL) {
261 if (!filter || filter(name, d))
262 strlist__add(list, d->d_name);
263 }
264
265out:
266 closedir(dir);
267 return list;
268}
269
270size_t hex_width(u64 v)
271{
272 size_t n = 1;
273
274 while ((v >>= 4))
275 ++n;
276
277 return n;
278}
279
280int perf_event_paranoid(void)
281{
282 int value;
283
284 if (sysctl__read_int("kernel/perf_event_paranoid", &value))
285 return INT_MAX;
286
287 return value;
288}
289
290bool perf_event_paranoid_check(int max_level)
291{
292 return perf_cap__capable(CAP_SYS_ADMIN) ||
293 perf_cap__capable(CAP_PERFMON) ||
294 perf_event_paranoid() <= max_level;
295}
296
297static int
298fetch_ubuntu_kernel_version(unsigned int *puint)
299{
300 ssize_t len;
301 size_t line_len = 0;
302 char *ptr, *line = NULL;
303 int version, patchlevel, sublevel, err;
304 FILE *vsig;
305
306 if (!puint)
307 return 0;
308
309 vsig = fopen("/proc/version_signature", "r");
310 if (!vsig) {
311 pr_debug("Open /proc/version_signature failed: %s\n",
312 strerror(errno));
313 return -1;
314 }
315
316 len = getline(&line, &line_len, vsig);
317 fclose(vsig);
318 err = -1;
319 if (len <= 0) {
320 pr_debug("Reading from /proc/version_signature failed: %s\n",
321 strerror(errno));
322 goto errout;
323 }
324
325 ptr = strrchr(line, ' ');
326 if (!ptr) {
327 pr_debug("Parsing /proc/version_signature failed: %s\n", line);
328 goto errout;
329 }
330
331 err = sscanf(ptr + 1, "%d.%d.%d",
332 &version, &patchlevel, &sublevel);
333 if (err != 3) {
334 pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
335 line);
336 goto errout;
337 }
338
339 *puint = (version << 16) + (patchlevel << 8) + sublevel;
340 err = 0;
341errout:
342 free(line);
343 return err;
344}
345
346int
347fetch_kernel_version(unsigned int *puint, char *str,
348 size_t str_size)
349{
350 struct utsname utsname;
351 int version, patchlevel, sublevel, err;
352 bool int_ver_ready = false;
353
354 if (access("/proc/version_signature", R_OK) == 0)
355 if (!fetch_ubuntu_kernel_version(puint))
356 int_ver_ready = true;
357
358 if (uname(&utsname))
359 return -1;
360
361 if (str && str_size) {
362 strncpy(str, utsname.release, str_size);
363 str[str_size - 1] = '\0';
364 }
365
366 if (!puint || int_ver_ready)
367 return 0;
368
369 err = sscanf(utsname.release, "%d.%d.%d",
370 &version, &patchlevel, &sublevel);
371
372 if (err != 3) {
373 pr_debug("Unable to get kernel version from uname '%s'\n",
374 utsname.release);
375 return -1;
376 }
377
378 *puint = (version << 16) + (patchlevel << 8) + sublevel;
379 return 0;
380}
381
382const char *perf_tip(const char *dirpath)
383{
384 struct strlist *tips;
385 struct str_node *node;
386 char *tip = NULL;
387 struct strlist_config conf = {
388 .dirname = dirpath,
389 .file_only = true,
390 };
391
392 tips = strlist__new("tips.txt", &conf);
393 if (tips == NULL)
394 return errno == ENOENT ? NULL :
395 "Tip: check path of tips.txt or get more memory! ;-p";
396
397 if (strlist__nr_entries(tips) == 0)
398 goto out;
399
400 node = strlist__entry(tips, random() % strlist__nr_entries(tips));
401 if (asprintf(&tip, "Tip: %s", node->s) < 0)
402 tip = (char *)"Tip: get more memory! ;-)";
403
404out:
405 strlist__delete(tips);
406
407 return tip;
408}
409
410char *perf_exe(char *buf, int len)
411{
412 int n = readlink("/proc/self/exe", buf, len);
413 if (n > 0) {
414 buf[n] = 0;
415 return buf;
416 }
417 return strcpy(buf, "perf");
418}