1 // SPDX-License-Identifier: GPL-2.0
2 #include "../perf.h"
3 #include "util.h"
4 #include "debug.h"
5 #include <api/fs/fs.h>
6 #include <sys/mman.h>
7 #include <sys/stat.h>
8 #include <sys/utsname.h>
9 #include <dirent.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/kernel.h>
18 #include <linux/log2.h>
19 #include <linux/time64.h>
20 #include <unistd.h>
21 #include "strlist.h"
22
23 /*
24 * XXX We need to find a better place for these things...
25 */
26 unsigned int page_size;
27 int cacheline_size;
28
29 int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
30 int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;
31
32 bool test_attr__enabled;
33
34 bool perf_host = true;
35 bool perf_guest = false;
36
event_attr_init(struct perf_event_attr * attr)37 void event_attr_init(struct perf_event_attr *attr)
38 {
39 if (!perf_host)
40 attr->exclude_host = 1;
41 if (!perf_guest)
42 attr->exclude_guest = 1;
43 /* to capture ABI version */
44 attr->size = sizeof(*attr);
45 }
46
mkdir_p(char * path,mode_t mode)47 int mkdir_p(char *path, mode_t mode)
48 {
49 struct stat st;
50 int err;
51 char *d = path;
52
53 if (*d != '/')
54 return -1;
55
56 if (stat(path, &st) == 0)
57 return 0;
58
59 while (*++d == '/');
60
61 while ((d = strchr(d, '/'))) {
62 *d = '\0';
63 err = stat(path, &st) && mkdir(path, mode);
64 *d++ = '/';
65 if (err)
66 return -1;
67 while (*d == '/')
68 ++d;
69 }
70 return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
71 }
72
rm_rf(const char * path)73 int rm_rf(const char *path)
74 {
75 DIR *dir;
76 int ret = 0;
77 struct dirent *d;
78 char namebuf[PATH_MAX];
79
80 dir = opendir(path);
81 if (dir == NULL)
82 return 0;
83
84 while ((d = readdir(dir)) != NULL && !ret) {
85 struct stat statbuf;
86
87 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
88 continue;
89
90 scnprintf(namebuf, sizeof(namebuf), "%s/%s",
91 path, d->d_name);
92
93 /* We have to check symbolic link itself */
94 ret = lstat(namebuf, &statbuf);
95 if (ret < 0) {
96 pr_debug("stat failed: %s\n", namebuf);
97 break;
98 }
99
100 if (S_ISDIR(statbuf.st_mode))
101 ret = rm_rf(namebuf);
102 else
103 ret = unlink(namebuf);
104 }
105 closedir(dir);
106
107 if (ret < 0)
108 return ret;
109
110 return rmdir(path);
111 }
112
113 /* A filter which removes dot files */
lsdir_no_dot_filter(const char * name __maybe_unused,struct dirent * d)114 bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d)
115 {
116 return d->d_name[0] != '.';
117 }
118
119 /* lsdir reads a directory and store it in strlist */
lsdir(const char * name,bool (* filter)(const char *,struct dirent *))120 struct strlist *lsdir(const char *name,
121 bool (*filter)(const char *, struct dirent *))
122 {
123 struct strlist *list = NULL;
124 DIR *dir;
125 struct dirent *d;
126
127 dir = opendir(name);
128 if (!dir)
129 return NULL;
130
131 list = strlist__new(NULL, NULL);
132 if (!list) {
133 errno = ENOMEM;
134 goto out;
135 }
136
137 while ((d = readdir(dir)) != NULL) {
138 if (!filter || filter(name, d))
139 strlist__add(list, d->d_name);
140 }
141
142 out:
143 closedir(dir);
144 return list;
145 }
146
slow_copyfile(const char * from,const char * to,struct nsinfo * nsi)147 static int slow_copyfile(const char *from, const char *to, struct nsinfo *nsi)
148 {
149 int err = -1;
150 char *line = NULL;
151 size_t n;
152 FILE *from_fp, *to_fp;
153 struct nscookie nsc;
154
155 nsinfo__mountns_enter(nsi, &nsc);
156 from_fp = fopen(from, "r");
157 nsinfo__mountns_exit(&nsc);
158 if (from_fp == NULL)
159 goto out;
160
161 to_fp = fopen(to, "w");
162 if (to_fp == NULL)
163 goto out_fclose_from;
164
165 while (getline(&line, &n, from_fp) > 0)
166 if (fputs(line, to_fp) == EOF)
167 goto out_fclose_to;
168 err = 0;
169 out_fclose_to:
170 fclose(to_fp);
171 free(line);
172 out_fclose_from:
173 fclose(from_fp);
174 out:
175 return err;
176 }
177
copyfile_offset(int ifd,loff_t off_in,int ofd,loff_t off_out,u64 size)178 int copyfile_offset(int ifd, loff_t off_in, int ofd, loff_t off_out, u64 size)
179 {
180 void *ptr;
181 loff_t pgoff;
182
183 pgoff = off_in & ~(page_size - 1);
184 off_in -= pgoff;
185
186 ptr = mmap(NULL, off_in + size, PROT_READ, MAP_PRIVATE, ifd, pgoff);
187 if (ptr == MAP_FAILED)
188 return -1;
189
190 while (size) {
191 ssize_t ret = pwrite(ofd, ptr + off_in, size, off_out);
192 if (ret < 0 && errno == EINTR)
193 continue;
194 if (ret <= 0)
195 break;
196
197 size -= ret;
198 off_in += ret;
199 off_out += ret;
200 }
201 munmap(ptr, off_in + size);
202
203 return size ? -1 : 0;
204 }
205
copyfile_mode_ns(const char * from,const char * to,mode_t mode,struct nsinfo * nsi)206 static int copyfile_mode_ns(const char *from, const char *to, mode_t mode,
207 struct nsinfo *nsi)
208 {
209 int fromfd, tofd;
210 struct stat st;
211 int err;
212 char *tmp = NULL, *ptr = NULL;
213 struct nscookie nsc;
214
215 nsinfo__mountns_enter(nsi, &nsc);
216 err = stat(from, &st);
217 nsinfo__mountns_exit(&nsc);
218 if (err)
219 goto out;
220 err = -1;
221
222 /* extra 'x' at the end is to reserve space for '.' */
223 if (asprintf(&tmp, "%s.XXXXXXx", to) < 0) {
224 tmp = NULL;
225 goto out;
226 }
227 ptr = strrchr(tmp, '/');
228 if (!ptr)
229 goto out;
230 ptr = memmove(ptr + 1, ptr, strlen(ptr) - 1);
231 *ptr = '.';
232
233 tofd = mkstemp(tmp);
234 if (tofd < 0)
235 goto out;
236
237 if (fchmod(tofd, mode))
238 goto out_close_to;
239
240 if (st.st_size == 0) { /* /proc? do it slowly... */
241 err = slow_copyfile(from, tmp, nsi);
242 goto out_close_to;
243 }
244
245 nsinfo__mountns_enter(nsi, &nsc);
246 fromfd = open(from, O_RDONLY);
247 nsinfo__mountns_exit(&nsc);
248 if (fromfd < 0)
249 goto out_close_to;
250
251 err = copyfile_offset(fromfd, 0, tofd, 0, st.st_size);
252
253 close(fromfd);
254 out_close_to:
255 close(tofd);
256 if (!err)
257 err = link(tmp, to);
258 unlink(tmp);
259 out:
260 free(tmp);
261 return err;
262 }
263
copyfile_ns(const char * from,const char * to,struct nsinfo * nsi)264 int copyfile_ns(const char *from, const char *to, struct nsinfo *nsi)
265 {
266 return copyfile_mode_ns(from, to, 0755, nsi);
267 }
268
copyfile_mode(const char * from,const char * to,mode_t mode)269 int copyfile_mode(const char *from, const char *to, mode_t mode)
270 {
271 return copyfile_mode_ns(from, to, mode, NULL);
272 }
273
copyfile(const char * from,const char * to)274 int copyfile(const char *from, const char *to)
275 {
276 return copyfile_mode(from, to, 0755);
277 }
278
ion(bool is_read,int fd,void * buf,size_t n)279 static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
280 {
281 void *buf_start = buf;
282 size_t left = n;
283
284 while (left) {
285 /* buf must be treated as const if !is_read. */
286 ssize_t ret = is_read ? read(fd, buf, left) :
287 write(fd, buf, left);
288
289 if (ret < 0 && errno == EINTR)
290 continue;
291 if (ret <= 0)
292 return ret;
293
294 left -= ret;
295 buf += ret;
296 }
297
298 BUG_ON((size_t)(buf - buf_start) != n);
299 return n;
300 }
301
302 /*
303 * Read exactly 'n' bytes or return an error.
304 */
readn(int fd,void * buf,size_t n)305 ssize_t readn(int fd, void *buf, size_t n)
306 {
307 return ion(true, fd, buf, n);
308 }
309
310 /*
311 * Write exactly 'n' bytes or return an error.
312 */
writen(int fd,const void * buf,size_t n)313 ssize_t writen(int fd, const void *buf, size_t n)
314 {
315 /* ion does not modify buf. */
316 return ion(false, fd, (void *)buf, n);
317 }
318
hex_width(u64 v)319 size_t hex_width(u64 v)
320 {
321 size_t n = 1;
322
323 while ((v >>= 4))
324 ++n;
325
326 return n;
327 }
328
hex(char ch)329 static int hex(char ch)
330 {
331 if ((ch >= '0') && (ch <= '9'))
332 return ch - '0';
333 if ((ch >= 'a') && (ch <= 'f'))
334 return ch - 'a' + 10;
335 if ((ch >= 'A') && (ch <= 'F'))
336 return ch - 'A' + 10;
337 return -1;
338 }
339
340 /*
341 * While we find nice hex chars, build a long_val.
342 * Return number of chars processed.
343 */
hex2u64(const char * ptr,u64 * long_val)344 int hex2u64(const char *ptr, u64 *long_val)
345 {
346 const char *p = ptr;
347 *long_val = 0;
348
349 while (*p) {
350 const int hex_val = hex(*p);
351
352 if (hex_val < 0)
353 break;
354
355 *long_val = (*long_val << 4) | hex_val;
356 p++;
357 }
358
359 return p - ptr;
360 }
361
perf_event_paranoid(void)362 int perf_event_paranoid(void)
363 {
364 int value;
365
366 if (sysctl__read_int("kernel/perf_event_paranoid", &value))
367 return INT_MAX;
368
369 return value;
370 }
371 static int
fetch_ubuntu_kernel_version(unsigned int * puint)372 fetch_ubuntu_kernel_version(unsigned int *puint)
373 {
374 ssize_t len;
375 size_t line_len = 0;
376 char *ptr, *line = NULL;
377 int version, patchlevel, sublevel, err;
378 FILE *vsig;
379
380 if (!puint)
381 return 0;
382
383 vsig = fopen("/proc/version_signature", "r");
384 if (!vsig) {
385 pr_debug("Open /proc/version_signature failed: %s\n",
386 strerror(errno));
387 return -1;
388 }
389
390 len = getline(&line, &line_len, vsig);
391 fclose(vsig);
392 err = -1;
393 if (len <= 0) {
394 pr_debug("Reading from /proc/version_signature failed: %s\n",
395 strerror(errno));
396 goto errout;
397 }
398
399 ptr = strrchr(line, ' ');
400 if (!ptr) {
401 pr_debug("Parsing /proc/version_signature failed: %s\n", line);
402 goto errout;
403 }
404
405 err = sscanf(ptr + 1, "%d.%d.%d",
406 &version, &patchlevel, &sublevel);
407 if (err != 3) {
408 pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
409 line);
410 goto errout;
411 }
412
413 *puint = (version << 16) + (patchlevel << 8) + sublevel;
414 err = 0;
415 errout:
416 free(line);
417 return err;
418 }
419
420 int
fetch_kernel_version(unsigned int * puint,char * str,size_t str_size)421 fetch_kernel_version(unsigned int *puint, char *str,
422 size_t str_size)
423 {
424 struct utsname utsname;
425 int version, patchlevel, sublevel, err;
426 bool int_ver_ready = false;
427
428 if (access("/proc/version_signature", R_OK) == 0)
429 if (!fetch_ubuntu_kernel_version(puint))
430 int_ver_ready = true;
431
432 if (uname(&utsname))
433 return -1;
434
435 if (str && str_size) {
436 strncpy(str, utsname.release, str_size);
437 str[str_size - 1] = '\0';
438 }
439
440 if (!puint || int_ver_ready)
441 return 0;
442
443 err = sscanf(utsname.release, "%d.%d.%d",
444 &version, &patchlevel, &sublevel);
445
446 if (err != 3) {
447 pr_debug("Unable to get kernel version from uname '%s'\n",
448 utsname.release);
449 return -1;
450 }
451
452 *puint = (version << 16) + (patchlevel << 8) + sublevel;
453 return 0;
454 }
455
perf_tip(const char * dirpath)456 const char *perf_tip(const char *dirpath)
457 {
458 struct strlist *tips;
459 struct str_node *node;
460 char *tip = NULL;
461 struct strlist_config conf = {
462 .dirname = dirpath,
463 .file_only = true,
464 };
465
466 tips = strlist__new("tips.txt", &conf);
467 if (tips == NULL)
468 return errno == ENOENT ? NULL :
469 "Tip: check path of tips.txt or get more memory! ;-p";
470
471 if (strlist__nr_entries(tips) == 0)
472 goto out;
473
474 node = strlist__entry(tips, random() % strlist__nr_entries(tips));
475 if (asprintf(&tip, "Tip: %s", node->s) < 0)
476 tip = (char *)"Tip: get more memory! ;-)";
477
478 out:
479 strlist__delete(tips);
480
481 return tip;
482 }
483