1 // SPDX-License-Identifier: GPL-2.0
7 #include <sys/utsname.h>
17 #include <linux/capability.h>
18 #include <linux/kernel.h>
19 #include <linux/log2.h>
20 #include <linux/time64.h>
27 * XXX We need to find a better place for these things...
30 bool perf_singlethreaded = true;
32 void perf_set_singlethreaded(void)
34 perf_singlethreaded = true;
37 void perf_set_multithreaded(void)
39 perf_singlethreaded = false;
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;
45 int sysctl__max_stack(void)
49 if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
50 sysctl_perf_event_max_stack = value;
52 if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
53 sysctl_perf_event_max_contexts_per_stack = value;
55 return sysctl_perf_event_max_stack;
58 bool sysctl__nmi_watchdog_enabled(void)
61 static bool nmi_watchdog;
67 if (sysctl__read_int("kernel/nmi_watchdog", &value) < 0)
70 nmi_watchdog = (value > 0) ? true : false;
76 bool test_attr__enabled;
78 bool perf_host = true;
79 bool perf_guest = false;
81 void event_attr_init(struct perf_event_attr *attr)
84 attr->exclude_host = 1;
86 attr->exclude_guest = 1;
87 /* to capture ABI version */
88 attr->size = sizeof(*attr);
91 int mkdir_p(char *path, mode_t mode)
100 if (stat(path, &st) == 0)
105 while ((d = strchr(d, '/'))) {
107 err = stat(path, &st) && mkdir(path, mode);
114 return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
117 static bool match_pat(char *file, const char **pat)
125 if (strglobmatch(file, pat[i]))
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
139 * If specified the pat is array of string patterns ended with NULL,
140 * which are checked upon every file/directory found. Only matching
143 * The function returns:
145 * -1 on removal failure with errno set
146 * -2 on pattern failure
148 static int rm_rf_depth_pat(const char *path, int depth, const char **pat)
153 char namebuf[PATH_MAX];
156 /* Do not fail if there's no file. */
157 ret = lstat(path, &statbuf);
161 /* Try to remove any file we get. */
162 if (!(statbuf.st_mode & S_IFDIR))
165 /* We have directory in path. */
170 while ((d = readdir(dir)) != NULL && !ret) {
172 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
175 if (!match_pat(d->d_name, pat)) {
180 scnprintf(namebuf, sizeof(namebuf), "%s/%s",
183 /* We have to check symbolic link itself */
184 ret = lstat(namebuf, &statbuf);
186 pr_debug("stat failed: %s\n", namebuf);
190 if (S_ISDIR(statbuf.st_mode))
191 ret = depth ? rm_rf_depth_pat(namebuf, depth - 1, pat) : 0;
193 ret = unlink(namebuf);
203 static int rm_rf_kcore_dir(const char *path)
205 char kcore_dir_path[PATH_MAX];
206 const char *pat[] = {
213 snprintf(kcore_dir_path, sizeof(kcore_dir_path), "%s/kcore_dir", path);
215 return rm_rf_depth_pat(kcore_dir_path, 0, pat);
218 int rm_rf_perf_data(const char *path)
220 const char *pat[] = {
226 rm_rf_kcore_dir(path);
228 return rm_rf_depth_pat(path, 0, pat);
231 int rm_rf(const char *path)
233 return rm_rf_depth_pat(path, INT_MAX, NULL);
236 /* A filter which removes dot files */
237 bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d)
239 return d->d_name[0] != '.';
242 /* lsdir reads a directory and store it in strlist */
243 struct strlist *lsdir(const char *name,
244 bool (*filter)(const char *, struct dirent *))
246 struct strlist *list = NULL;
254 list = strlist__new(NULL, NULL);
260 while ((d = readdir(dir)) != NULL) {
261 if (!filter || filter(name, d))
262 strlist__add(list, d->d_name);
270 size_t hex_width(u64 v)
280 int perf_event_paranoid(void)
284 if (sysctl__read_int("kernel/perf_event_paranoid", &value))
290 bool perf_event_paranoid_check(int max_level)
292 return perf_cap__capable(CAP_SYS_ADMIN) ||
293 perf_cap__capable(CAP_PERFMON) ||
294 perf_event_paranoid() <= max_level;
298 fetch_ubuntu_kernel_version(unsigned int *puint)
302 char *ptr, *line = NULL;
303 int version, patchlevel, sublevel, err;
309 vsig = fopen("/proc/version_signature", "r");
311 pr_debug("Open /proc/version_signature failed: %s\n",
316 len = getline(&line, &line_len, vsig);
320 pr_debug("Reading from /proc/version_signature failed: %s\n",
325 ptr = strrchr(line, ' ');
327 pr_debug("Parsing /proc/version_signature failed: %s\n", line);
331 err = sscanf(ptr + 1, "%d.%d.%d",
332 &version, &patchlevel, &sublevel);
334 pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
339 *puint = (version << 16) + (patchlevel << 8) + sublevel;
347 fetch_kernel_version(unsigned int *puint, char *str,
350 struct utsname utsname;
351 int version, patchlevel, sublevel, err;
352 bool int_ver_ready = false;
354 if (access("/proc/version_signature", R_OK) == 0)
355 if (!fetch_ubuntu_kernel_version(puint))
356 int_ver_ready = true;
361 if (str && str_size) {
362 strncpy(str, utsname.release, str_size);
363 str[str_size - 1] = '\0';
366 if (!puint || int_ver_ready)
369 err = sscanf(utsname.release, "%d.%d.%d",
370 &version, &patchlevel, &sublevel);
373 pr_debug("Unable to get kernel version from uname '%s'\n",
378 *puint = (version << 16) + (patchlevel << 8) + sublevel;
382 int perf_tip(char **strp, const char *dirpath)
384 struct strlist *tips;
385 struct str_node *node;
386 struct strlist_config conf = {
393 tips = strlist__new("tips.txt", &conf);
397 if (strlist__nr_entries(tips) == 0)
400 node = strlist__entry(tips, random() % strlist__nr_entries(tips));
401 if (asprintf(strp, "Tip: %s", node->s) < 0)
405 strlist__delete(tips);
410 char *perf_exe(char *buf, int len)
412 int n = readlink("/proc/self/exe", buf, len);
417 return strcpy(buf, "perf");
420 void perf_debuginfod_setup(struct perf_debuginfod *di)
423 * By default '!di->set' we clear DEBUGINFOD_URLS, so debuginfod
424 * processing is not triggered, otherwise we set it to 'di->urls'
425 * value. If 'di->urls' is "system" we keep DEBUGINFOD_URLS value.
428 setenv("DEBUGINFOD_URLS", "", 1);
429 else if (di->urls && strcmp(di->urls, "system"))
430 setenv("DEBUGINFOD_URLS", di->urls, 1);
432 pr_debug("DEBUGINFOD_URLS=%s\n", getenv("DEBUGINFOD_URLS"));
436 * Return a new filename prepended with task's root directory if it's in
437 * a chroot. Callers should free the returned string.
439 char *filename_with_chroot(int pid, const char *filename)
443 char *new_name = NULL;
446 scnprintf(proc_root, sizeof(proc_root), "/proc/%d/root", pid);
447 ret = readlink(proc_root, buf, sizeof(buf) - 1);
451 /* readlink(2) does not append a null byte to buf */
454 if (!strcmp(buf, "/"))
457 if (strstr(buf, "(deleted)"))
460 if (asprintf(&new_name, "%s/%s", buf, filename) < 0)