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
30 bool perf_singlethreaded = true;
31
perf_set_singlethreaded(void)32 void perf_set_singlethreaded(void)
33 {
34 perf_singlethreaded = true;
35 }
36
perf_set_multithreaded(void)37 void perf_set_multithreaded(void)
38 {
39 perf_singlethreaded = false;
40 }
41
42 int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
43 int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;
44
sysctl__max_stack(void)45 int 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
58 bool test_attr__enabled;
59
60 bool perf_host = true;
61 bool perf_guest = false;
62
event_attr_init(struct perf_event_attr * attr)63 void event_attr_init(struct perf_event_attr *attr)
64 {
65 if (!perf_host)
66 attr->exclude_host = 1;
67 if (!perf_guest)
68 attr->exclude_guest = 1;
69 /* to capture ABI version */
70 attr->size = sizeof(*attr);
71 }
72
mkdir_p(char * path,mode_t mode)73 int mkdir_p(char *path, mode_t mode)
74 {
75 struct stat st;
76 int err;
77 char *d = path;
78
79 if (*d != '/')
80 return -1;
81
82 if (stat(path, &st) == 0)
83 return 0;
84
85 while (*++d == '/');
86
87 while ((d = strchr(d, '/'))) {
88 *d = '\0';
89 err = stat(path, &st) && mkdir(path, mode);
90 *d++ = '/';
91 if (err)
92 return -1;
93 while (*d == '/')
94 ++d;
95 }
96 return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
97 }
98
match_pat(char * file,const char ** pat)99 static bool match_pat(char *file, const char **pat)
100 {
101 int i = 0;
102
103 if (!pat)
104 return true;
105
106 while (pat[i]) {
107 if (strglobmatch(file, pat[i]))
108 return true;
109
110 i++;
111 }
112
113 return false;
114 }
115
116 /*
117 * The depth specify how deep the removal will go.
118 * 0 - will remove only files under the 'path' directory
119 * 1 .. x - will dive in x-level deep under the 'path' directory
120 *
121 * If specified the pat is array of string patterns ended with NULL,
122 * which are checked upon every file/directory found. Only matching
123 * ones are removed.
124 *
125 * The function returns:
126 * 0 on success
127 * -1 on removal failure with errno set
128 * -2 on pattern failure
129 */
rm_rf_depth_pat(const char * path,int depth,const char ** pat)130 static int rm_rf_depth_pat(const char *path, int depth, const char **pat)
131 {
132 DIR *dir;
133 int ret;
134 struct dirent *d;
135 char namebuf[PATH_MAX];
136 struct stat statbuf;
137
138 /* Do not fail if there's no file. */
139 ret = lstat(path, &statbuf);
140 if (ret)
141 return 0;
142
143 /* Try to remove any file we get. */
144 if (!(statbuf.st_mode & S_IFDIR))
145 return unlink(path);
146
147 /* We have directory in path. */
148 dir = opendir(path);
149 if (dir == NULL)
150 return -1;
151
152 while ((d = readdir(dir)) != NULL && !ret) {
153
154 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
155 continue;
156
157 if (!match_pat(d->d_name, pat)) {
158 ret = -2;
159 break;
160 }
161
162 scnprintf(namebuf, sizeof(namebuf), "%s/%s",
163 path, d->d_name);
164
165 /* We have to check symbolic link itself */
166 ret = lstat(namebuf, &statbuf);
167 if (ret < 0) {
168 pr_debug("stat failed: %s\n", namebuf);
169 break;
170 }
171
172 if (S_ISDIR(statbuf.st_mode))
173 ret = depth ? rm_rf_depth_pat(namebuf, depth - 1, pat) : 0;
174 else
175 ret = unlink(namebuf);
176 }
177 closedir(dir);
178
179 if (ret < 0)
180 return ret;
181
182 return rmdir(path);
183 }
184
rm_rf_perf_data(const char * path)185 int rm_rf_perf_data(const char *path)
186 {
187 const char *pat[] = {
188 "header",
189 "data.*",
190 NULL,
191 };
192
193 return rm_rf_depth_pat(path, 0, pat);
194 }
195
rm_rf(const char * path)196 int rm_rf(const char *path)
197 {
198 return rm_rf_depth_pat(path, INT_MAX, NULL);
199 }
200
201 /* A filter which removes dot files */
lsdir_no_dot_filter(const char * name __maybe_unused,struct dirent * d)202 bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d)
203 {
204 return d->d_name[0] != '.';
205 }
206
207 /* lsdir reads a directory and store it in strlist */
lsdir(const char * name,bool (* filter)(const char *,struct dirent *))208 struct strlist *lsdir(const char *name,
209 bool (*filter)(const char *, struct dirent *))
210 {
211 struct strlist *list = NULL;
212 DIR *dir;
213 struct dirent *d;
214
215 dir = opendir(name);
216 if (!dir)
217 return NULL;
218
219 list = strlist__new(NULL, NULL);
220 if (!list) {
221 errno = ENOMEM;
222 goto out;
223 }
224
225 while ((d = readdir(dir)) != NULL) {
226 if (!filter || filter(name, d))
227 strlist__add(list, d->d_name);
228 }
229
230 out:
231 closedir(dir);
232 return list;
233 }
234
hex_width(u64 v)235 size_t hex_width(u64 v)
236 {
237 size_t n = 1;
238
239 while ((v >>= 4))
240 ++n;
241
242 return n;
243 }
244
perf_event_paranoid(void)245 int perf_event_paranoid(void)
246 {
247 int value;
248
249 if (sysctl__read_int("kernel/perf_event_paranoid", &value))
250 return INT_MAX;
251
252 return value;
253 }
254
perf_event_paranoid_check(int max_level)255 bool perf_event_paranoid_check(int max_level)
256 {
257 return perf_cap__capable(CAP_SYS_ADMIN) ||
258 perf_event_paranoid() <= max_level;
259 }
260
261 static int
fetch_ubuntu_kernel_version(unsigned int * puint)262 fetch_ubuntu_kernel_version(unsigned int *puint)
263 {
264 ssize_t len;
265 size_t line_len = 0;
266 char *ptr, *line = NULL;
267 int version, patchlevel, sublevel, err;
268 FILE *vsig;
269
270 if (!puint)
271 return 0;
272
273 vsig = fopen("/proc/version_signature", "r");
274 if (!vsig) {
275 pr_debug("Open /proc/version_signature failed: %s\n",
276 strerror(errno));
277 return -1;
278 }
279
280 len = getline(&line, &line_len, vsig);
281 fclose(vsig);
282 err = -1;
283 if (len <= 0) {
284 pr_debug("Reading from /proc/version_signature failed: %s\n",
285 strerror(errno));
286 goto errout;
287 }
288
289 ptr = strrchr(line, ' ');
290 if (!ptr) {
291 pr_debug("Parsing /proc/version_signature failed: %s\n", line);
292 goto errout;
293 }
294
295 err = sscanf(ptr + 1, "%d.%d.%d",
296 &version, &patchlevel, &sublevel);
297 if (err != 3) {
298 pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
299 line);
300 goto errout;
301 }
302
303 *puint = (version << 16) + (patchlevel << 8) + sublevel;
304 err = 0;
305 errout:
306 free(line);
307 return err;
308 }
309
310 int
fetch_kernel_version(unsigned int * puint,char * str,size_t str_size)311 fetch_kernel_version(unsigned int *puint, char *str,
312 size_t str_size)
313 {
314 struct utsname utsname;
315 int version, patchlevel, sublevel, err;
316 bool int_ver_ready = false;
317
318 if (access("/proc/version_signature", R_OK) == 0)
319 if (!fetch_ubuntu_kernel_version(puint))
320 int_ver_ready = true;
321
322 if (uname(&utsname))
323 return -1;
324
325 if (str && str_size) {
326 strncpy(str, utsname.release, str_size);
327 str[str_size - 1] = '\0';
328 }
329
330 if (!puint || int_ver_ready)
331 return 0;
332
333 err = sscanf(utsname.release, "%d.%d.%d",
334 &version, &patchlevel, &sublevel);
335
336 if (err != 3) {
337 pr_debug("Unable to get kernel version from uname '%s'\n",
338 utsname.release);
339 return -1;
340 }
341
342 *puint = (version << 16) + (patchlevel << 8) + sublevel;
343 return 0;
344 }
345
perf_tip(const char * dirpath)346 const char *perf_tip(const char *dirpath)
347 {
348 struct strlist *tips;
349 struct str_node *node;
350 char *tip = NULL;
351 struct strlist_config conf = {
352 .dirname = dirpath,
353 .file_only = true,
354 };
355
356 tips = strlist__new("tips.txt", &conf);
357 if (tips == NULL)
358 return errno == ENOENT ? NULL :
359 "Tip: check path of tips.txt or get more memory! ;-p";
360
361 if (strlist__nr_entries(tips) == 0)
362 goto out;
363
364 node = strlist__entry(tips, random() % strlist__nr_entries(tips));
365 if (asprintf(&tip, "Tip: %s", node->s) < 0)
366 tip = (char *)"Tip: get more memory! ;-)";
367
368 out:
369 strlist__delete(tips);
370
371 return tip;
372 }
373
perf_exe(char * buf,int len)374 char *perf_exe(char *buf, int len)
375 {
376 int n = readlink("/proc/self/exe", buf, len);
377 if (n > 0) {
378 buf[n] = 0;
379 return buf;
380 }
381 return strcpy(buf, "perf");
382 }
383
