1 // SPDX-License-Identifier: GPL-2.0
2 #include <dirent.h>
3 #include <errno.h>
4 #include <limits.h>
5 #include <stdbool.h>
6 #include <stdlib.h>
7 #include <stdio.h>
8 #include <sys/types.h>
9 #include <sys/stat.h>
10 #include <unistd.h>
11 #include "string2.h"
12 #include "strlist.h"
13 #include <string.h>
14 #include <api/fs/fs.h>
15 #include <linux/string.h>
16 #include <linux/zalloc.h>
17 #include "asm/bug.h"
18 #include "thread_map.h"
19 #include "debug.h"
20 #include "event.h"
21 #include <internal/threadmap.h>
22
23 /* Skip "." and ".." directories */
24 static int filter(const struct dirent *dir)
25 {
26 if (dir->d_name[0] == '.')
27 return 0;
28 else
29 return 1;
30 }
31
32 #define thread_map__alloc(__nr) perf_thread_map__realloc(NULL, __nr)
33
34 struct perf_thread_map *thread_map__new_by_pid(pid_t pid)
35 {
36 struct perf_thread_map *threads;
37 char name[256];
38 int items;
39 struct dirent **namelist = NULL;
40 int i;
41
42 sprintf(name, "/proc/%d/task", pid);
43 items = scandir(name, &namelist, filter, NULL);
44 if (items <= 0)
45 return NULL;
46
47 threads = thread_map__alloc(items);
48 if (threads != NULL) {
49 for (i = 0; i < items; i++)
50 perf_thread_map__set_pid(threads, i, atoi(namelist[i]->d_name));
51 threads->nr = items;
52 refcount_set(&threads->refcnt, 1);
53 }
54
55 for (i=0; i<items; i++)
56 zfree(&namelist[i]);
57 free(namelist);
58
59 return threads;
60 }
61
62 struct perf_thread_map *thread_map__new_by_tid(pid_t tid)
63 {
64 struct perf_thread_map *threads = thread_map__alloc(1);
65
66 if (threads != NULL) {
67 perf_thread_map__set_pid(threads, 0, tid);
68 threads->nr = 1;
69 refcount_set(&threads->refcnt, 1);
70 }
71
72 return threads;
73 }
74
75 static struct perf_thread_map *__thread_map__new_all_cpus(uid_t uid)
76 {
77 DIR *proc;
78 int max_threads = 32, items, i;
79 char path[NAME_MAX + 1 + 6];
80 struct dirent *dirent, **namelist = NULL;
81 struct perf_thread_map *threads = thread_map__alloc(max_threads);
82
83 if (threads == NULL)
84 goto out;
85
86 proc = opendir("/proc");
87 if (proc == NULL)
88 goto out_free_threads;
89
90 threads->nr = 0;
91 refcount_set(&threads->refcnt, 1);
92
93 while ((dirent = readdir(proc)) != NULL) {
94 char *end;
95 bool grow = false;
96 pid_t pid = strtol(dirent->d_name, &end, 10);
97
98 if (*end) /* only interested in proper numerical dirents */
99 continue;
100
101 snprintf(path, sizeof(path), "/proc/%s", dirent->d_name);
102
103 if (uid != UINT_MAX) {
104 struct stat st;
105
106 if (stat(path, &st) != 0 || st.st_uid != uid)
107 continue;
108 }
109
110 snprintf(path, sizeof(path), "/proc/%d/task", pid);
111 items = scandir(path, &namelist, filter, NULL);
112 if (items <= 0) {
113 pr_debug("scandir for %d returned empty, skipping\n", pid);
114 continue;
115 }
116 while (threads->nr + items >= max_threads) {
117 max_threads *= 2;
118 grow = true;
119 }
120
121 if (grow) {
122 struct perf_thread_map *tmp;
123
124 tmp = perf_thread_map__realloc(threads, max_threads);
125 if (tmp == NULL)
126 goto out_free_namelist;
127
128 threads = tmp;
129 }
130
131 for (i = 0; i < items; i++) {
132 perf_thread_map__set_pid(threads, threads->nr + i,
133 atoi(namelist[i]->d_name));
134 }
135
136 for (i = 0; i < items; i++)
137 zfree(&namelist[i]);
138 free(namelist);
139
140 threads->nr += items;
141 }
142
143 out_closedir:
144 closedir(proc);
145 out:
146 return threads;
147
148 out_free_threads:
149 free(threads);
150 return NULL;
151
152 out_free_namelist:
153 for (i = 0; i < items; i++)
154 zfree(&namelist[i]);
155 free(namelist);
156 zfree(&threads);
157 goto out_closedir;
158 }
159
160 struct perf_thread_map *thread_map__new_all_cpus(void)
161 {
162 return __thread_map__new_all_cpus(UINT_MAX);
163 }
164
165 struct perf_thread_map *thread_map__new_by_uid(uid_t uid)
166 {
167 return __thread_map__new_all_cpus(uid);
168 }
169
170 struct perf_thread_map *thread_map__new(pid_t pid, pid_t tid, uid_t uid)
171 {
172 if (pid != -1)
173 return thread_map__new_by_pid(pid);
174
175 if (tid == -1 && uid != UINT_MAX)
176 return thread_map__new_by_uid(uid);
177
178 return thread_map__new_by_tid(tid);
179 }
180
181 static struct perf_thread_map *thread_map__new_by_pid_str(const char *pid_str)
182 {
183 struct perf_thread_map *threads = NULL, *nt;
184 char name[256];
185 int items, total_tasks = 0;
186 struct dirent **namelist = NULL;
187 int i, j = 0;
188 pid_t pid, prev_pid = INT_MAX;
189 char *end_ptr;
190 struct str_node *pos;
191 struct strlist_config slist_config = { .dont_dupstr = true, };
192 struct strlist *slist = strlist__new(pid_str, &slist_config);
193
194 if (!slist)
195 return NULL;
196
197 strlist__for_each_entry(pos, slist) {
198 pid = strtol(pos->s, &end_ptr, 10);
199
200 if (pid == INT_MIN || pid == INT_MAX ||
201 (*end_ptr != '\0' && *end_ptr != ','))
202 goto out_free_threads;
203
204 if (pid == prev_pid)
205 continue;
206
207 sprintf(name, "/proc/%d/task", pid);
208 items = scandir(name, &namelist, filter, NULL);
209 if (items <= 0)
210 goto out_free_threads;
211
212 total_tasks += items;
213 nt = perf_thread_map__realloc(threads, total_tasks);
214 if (nt == NULL)
215 goto out_free_namelist;
216
217 threads = nt;
218
219 for (i = 0; i < items; i++) {
220 perf_thread_map__set_pid(threads, j++, atoi(namelist[i]->d_name));
221 zfree(&namelist[i]);
222 }
223 threads->nr = total_tasks;
224 free(namelist);
225 }
226
227 out:
228 strlist__delete(slist);
229 if (threads)
230 refcount_set(&threads->refcnt, 1);
231 return threads;
232
233 out_free_namelist:
234 for (i = 0; i < items; i++)
235 zfree(&namelist[i]);
236 free(namelist);
237
238 out_free_threads:
239 zfree(&threads);
240 goto out;
241 }
242
243 struct perf_thread_map *thread_map__new_by_tid_str(const char *tid_str)
244 {
245 struct perf_thread_map *threads = NULL, *nt;
246 int ntasks = 0;
247 pid_t tid, prev_tid = INT_MAX;
248 char *end_ptr;
249 struct str_node *pos;
250 struct strlist_config slist_config = { .dont_dupstr = true, };
251 struct strlist *slist;
252
253 /* perf-stat expects threads to be generated even if tid not given */
254 if (!tid_str)
255 return perf_thread_map__new_dummy();
256
257 slist = strlist__new(tid_str, &slist_config);
258 if (!slist)
259 return NULL;
260
261 strlist__for_each_entry(pos, slist) {
262 tid = strtol(pos->s, &end_ptr, 10);
263
264 if (tid == INT_MIN || tid == INT_MAX ||
265 (*end_ptr != '\0' && *end_ptr != ','))
266 goto out_free_threads;
267
268 if (tid == prev_tid)
269 continue;
270
271 ntasks++;
272 nt = perf_thread_map__realloc(threads, ntasks);
273
274 if (nt == NULL)
275 goto out_free_threads;
276
277 threads = nt;
278 perf_thread_map__set_pid(threads, ntasks - 1, tid);
279 threads->nr = ntasks;
280 }
281 out:
282 strlist__delete(slist);
283 if (threads)
284 refcount_set(&threads->refcnt, 1);
285 return threads;
286
287 out_free_threads:
288 zfree(&threads);
289 goto out;
290 }
291
292 struct perf_thread_map *thread_map__new_str(const char *pid, const char *tid,
293 uid_t uid, bool all_threads)
294 {
295 if (pid)
296 return thread_map__new_by_pid_str(pid);
297
298 if (!tid && uid != UINT_MAX)
299 return thread_map__new_by_uid(uid);
300
301 if (all_threads)
302 return thread_map__new_all_cpus();
303
304 return thread_map__new_by_tid_str(tid);
305 }
306
307 size_t thread_map__fprintf(struct perf_thread_map *threads, FILE *fp)
308 {
309 int i;
310 size_t printed = fprintf(fp, "%d thread%s: ",
311 threads->nr, threads->nr > 1 ? "s" : "");
312 for (i = 0; i < threads->nr; ++i)
313 printed += fprintf(fp, "%s%d", i ? ", " : "", perf_thread_map__pid(threads, i));
314
315 return printed + fprintf(fp, "\n");
316 }
317
318 static int get_comm(char **comm, pid_t pid)
319 {
320 char *path;
321 size_t size;
322 int err;
323
324 if (asprintf(&path, "%s/%d/comm", procfs__mountpoint(), pid) == -1)
325 return -ENOMEM;
326
327 err = filename__read_str(path, comm, &size);
328 if (!err) {
329 /*
330 * We're reading 16 bytes, while filename__read_str
331 * allocates data per BUFSIZ bytes, so we can safely
332 * mark the end of the string.
333 */
334 (*comm)[size] = 0;
335 strim(*comm);
336 }
337
338 free(path);
339 return err;
340 }
341
342 static void comm_init(struct perf_thread_map *map, int i)
343 {
344 pid_t pid = perf_thread_map__pid(map, i);
345 char *comm = NULL;
346
347 /* dummy pid comm initialization */
348 if (pid == -1) {
349 map->map[i].comm = strdup("dummy");
350 return;
351 }
352
353 /*
354 * The comm name is like extra bonus ;-),
355 * so just warn if we fail for any reason.
356 */
357 if (get_comm(&comm, pid))
358 pr_warning("Couldn't resolve comm name for pid %d\n", pid);
359
360 map->map[i].comm = comm;
361 }
362
363 void thread_map__read_comms(struct perf_thread_map *threads)
364 {
365 int i;
366
367 for (i = 0; i < threads->nr; ++i)
368 comm_init(threads, i);
369 }
370
371 static void thread_map__copy_event(struct perf_thread_map *threads,
372 struct perf_record_thread_map *event)
373 {
374 unsigned i;
375
376 threads->nr = (int) event->nr;
377
378 for (i = 0; i < event->nr; i++) {
379 perf_thread_map__set_pid(threads, i, (pid_t) event->entries[i].pid);
380 threads->map[i].comm = strndup(event->entries[i].comm, 16);
381 }
382
383 refcount_set(&threads->refcnt, 1);
384 }
385
386 struct perf_thread_map *thread_map__new_event(struct perf_record_thread_map *event)
387 {
388 struct perf_thread_map *threads;
389
390 threads = thread_map__alloc(event->nr);
391 if (threads)
392 thread_map__copy_event(threads, event);
393
394 return threads;
395 }
396
397 bool thread_map__has(struct perf_thread_map *threads, pid_t pid)
398 {
399 int i;
400
401 for (i = 0; i < threads->nr; ++i) {
402 if (threads->map[i].pid == pid)
403 return true;
404 }
405
406 return false;
407 }
408
409 int thread_map__remove(struct perf_thread_map *threads, int idx)
410 {
411 int i;
412
413 if (threads->nr < 1)
414 return -EINVAL;
415
416 if (idx >= threads->nr)
417 return -EINVAL;
418
419 /*
420 * Free the 'idx' item and shift the rest up.
421 */
422 zfree(&threads->map[idx].comm);
423
424 for (i = idx; i < threads->nr - 1; i++)
425 threads->map[i] = threads->map[i + 1];
426
427 threads->nr--;
428 return 0;
429 }
430
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