xref: /linux/tools/perf/builtin-buildid-cache.c (revision 48dea9a700c8728cc31a1dd44588b97578de86ee)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * builtin-buildid-cache.c
4  *
5  * Builtin buildid-cache command: Manages build-id cache
6  *
7  * Copyright (C) 2010, Red Hat Inc.
8  * Copyright (C) 2010, Arnaldo Carvalho de Melo <acme@redhat.com>
9  */
10 #include <sys/types.h>
11 #include <sys/time.h>
12 #include <time.h>
13 #include <dirent.h>
14 #include <errno.h>
15 #include <unistd.h>
16 #include "builtin.h"
17 #include "namespaces.h"
18 #include "util/debug.h"
19 #include "util/header.h"
20 #include <subcmd/pager.h>
21 #include <subcmd/parse-options.h>
22 #include "util/strlist.h"
23 #include "util/build-id.h"
24 #include "util/session.h"
25 #include "util/dso.h"
26 #include "util/symbol.h"
27 #include "util/time-utils.h"
28 #include "util/util.h"
29 #include "util/probe-file.h"
30 #include <linux/string.h>
31 #include <linux/err.h>
32 
33 static int build_id_cache__kcore_buildid(const char *proc_dir, char *sbuildid)
34 {
35 	char root_dir[PATH_MAX];
36 	char *p;
37 
38 	strlcpy(root_dir, proc_dir, sizeof(root_dir));
39 
40 	p = strrchr(root_dir, '/');
41 	if (!p)
42 		return -1;
43 	*p = '\0';
44 	return sysfs__sprintf_build_id(root_dir, sbuildid);
45 }
46 
47 static int build_id_cache__kcore_dir(char *dir, size_t sz)
48 {
49 	return fetch_current_timestamp(dir, sz);
50 }
51 
52 static bool same_kallsyms_reloc(const char *from_dir, char *to_dir)
53 {
54 	char from[PATH_MAX];
55 	char to[PATH_MAX];
56 	const char *name;
57 	u64 addr1 = 0, addr2 = 0;
58 	int i, err = -1;
59 
60 	scnprintf(from, sizeof(from), "%s/kallsyms", from_dir);
61 	scnprintf(to, sizeof(to), "%s/kallsyms", to_dir);
62 
63 	for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) {
64 		err = kallsyms__get_function_start(from, name, &addr1);
65 		if (!err)
66 			break;
67 	}
68 
69 	if (err)
70 		return false;
71 
72 	if (kallsyms__get_function_start(to, name, &addr2))
73 		return false;
74 
75 	return addr1 == addr2;
76 }
77 
78 static int build_id_cache__kcore_existing(const char *from_dir, char *to_dir,
79 					  size_t to_dir_sz)
80 {
81 	char from[PATH_MAX];
82 	char to[PATH_MAX];
83 	char to_subdir[PATH_MAX];
84 	struct dirent *dent;
85 	int ret = -1;
86 	DIR *d;
87 
88 	d = opendir(to_dir);
89 	if (!d)
90 		return -1;
91 
92 	scnprintf(from, sizeof(from), "%s/modules", from_dir);
93 
94 	while (1) {
95 		dent = readdir(d);
96 		if (!dent)
97 			break;
98 		if (dent->d_type != DT_DIR)
99 			continue;
100 		scnprintf(to, sizeof(to), "%s/%s/modules", to_dir,
101 			  dent->d_name);
102 		scnprintf(to_subdir, sizeof(to_subdir), "%s/%s",
103 			  to_dir, dent->d_name);
104 		if (!compare_proc_modules(from, to) &&
105 		    same_kallsyms_reloc(from_dir, to_subdir)) {
106 			strlcpy(to_dir, to_subdir, to_dir_sz);
107 			ret = 0;
108 			break;
109 		}
110 	}
111 
112 	closedir(d);
113 
114 	return ret;
115 }
116 
117 static int build_id_cache__add_kcore(const char *filename, bool force)
118 {
119 	char dir[32], sbuildid[SBUILD_ID_SIZE];
120 	char from_dir[PATH_MAX], to_dir[PATH_MAX];
121 	char *p;
122 
123 	strlcpy(from_dir, filename, sizeof(from_dir));
124 
125 	p = strrchr(from_dir, '/');
126 	if (!p || strcmp(p + 1, "kcore"))
127 		return -1;
128 	*p = '\0';
129 
130 	if (build_id_cache__kcore_buildid(from_dir, sbuildid) < 0)
131 		return -1;
132 
133 	scnprintf(to_dir, sizeof(to_dir), "%s/%s/%s",
134 		  buildid_dir, DSO__NAME_KCORE, sbuildid);
135 
136 	if (!force &&
137 	    !build_id_cache__kcore_existing(from_dir, to_dir, sizeof(to_dir))) {
138 		pr_debug("same kcore found in %s\n", to_dir);
139 		return 0;
140 	}
141 
142 	if (build_id_cache__kcore_dir(dir, sizeof(dir)))
143 		return -1;
144 
145 	scnprintf(to_dir, sizeof(to_dir), "%s/%s/%s/%s",
146 		  buildid_dir, DSO__NAME_KCORE, sbuildid, dir);
147 
148 	if (mkdir_p(to_dir, 0755))
149 		return -1;
150 
151 	if (kcore_copy(from_dir, to_dir)) {
152 		/* Remove YYYYmmddHHMMSShh directory */
153 		if (!rmdir(to_dir)) {
154 			p = strrchr(to_dir, '/');
155 			if (p)
156 				*p = '\0';
157 			/* Try to remove buildid directory */
158 			if (!rmdir(to_dir)) {
159 				p = strrchr(to_dir, '/');
160 				if (p)
161 					*p = '\0';
162 				/* Try to remove [kernel.kcore] directory */
163 				rmdir(to_dir);
164 			}
165 		}
166 		return -1;
167 	}
168 
169 	pr_debug("kcore added to build-id cache directory %s\n", to_dir);
170 
171 	return 0;
172 }
173 
174 static int build_id_cache__add_file(const char *filename, struct nsinfo *nsi)
175 {
176 	char sbuild_id[SBUILD_ID_SIZE];
177 	u8 build_id[BUILD_ID_SIZE];
178 	int err;
179 	struct nscookie nsc;
180 
181 	nsinfo__mountns_enter(nsi, &nsc);
182 	err = filename__read_build_id(filename, &build_id, sizeof(build_id));
183 	nsinfo__mountns_exit(&nsc);
184 	if (err < 0) {
185 		pr_debug("Couldn't read a build-id in %s\n", filename);
186 		return -1;
187 	}
188 
189 	build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
190 	err = build_id_cache__add_s(sbuild_id, filename, nsi,
191 				    false, false);
192 	pr_debug("Adding %s %s: %s\n", sbuild_id, filename,
193 		 err ? "FAIL" : "Ok");
194 	return err;
195 }
196 
197 static int build_id_cache__remove_file(const char *filename, struct nsinfo *nsi)
198 {
199 	u8 build_id[BUILD_ID_SIZE];
200 	char sbuild_id[SBUILD_ID_SIZE];
201 	struct nscookie nsc;
202 
203 	int err;
204 
205 	nsinfo__mountns_enter(nsi, &nsc);
206 	err = filename__read_build_id(filename, &build_id, sizeof(build_id));
207 	nsinfo__mountns_exit(&nsc);
208 	if (err < 0) {
209 		pr_debug("Couldn't read a build-id in %s\n", filename);
210 		return -1;
211 	}
212 
213 	build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
214 	err = build_id_cache__remove_s(sbuild_id);
215 	pr_debug("Removing %s %s: %s\n", sbuild_id, filename,
216 		 err ? "FAIL" : "Ok");
217 
218 	return err;
219 }
220 
221 static int build_id_cache__purge_path(const char *pathname, struct nsinfo *nsi)
222 {
223 	struct strlist *list;
224 	struct str_node *pos;
225 	int err;
226 
227 	err = build_id_cache__list_build_ids(pathname, nsi, &list);
228 	if (err)
229 		goto out;
230 
231 	strlist__for_each_entry(pos, list) {
232 		err = build_id_cache__remove_s(pos->s);
233 		pr_debug("Removing %s %s: %s\n", pos->s, pathname,
234 			 err ? "FAIL" : "Ok");
235 		if (err)
236 			break;
237 	}
238 	strlist__delete(list);
239 
240 out:
241 	pr_debug("Purging %s: %s\n", pathname, err ? "FAIL" : "Ok");
242 
243 	return err;
244 }
245 
246 static int build_id_cache__purge_all(void)
247 {
248 	struct strlist *list;
249 	struct str_node *pos;
250 	int err = 0;
251 	char *buf;
252 
253 	list = build_id_cache__list_all(false);
254 	if (!list) {
255 		pr_debug("Failed to get buildids: -%d\n", errno);
256 		return -EINVAL;
257 	}
258 
259 	strlist__for_each_entry(pos, list) {
260 		buf = build_id_cache__origname(pos->s);
261 		err = build_id_cache__remove_s(pos->s);
262 		pr_debug("Removing %s (%s): %s\n", buf, pos->s,
263 			 err ? "FAIL" : "Ok");
264 		free(buf);
265 		if (err)
266 			break;
267 	}
268 	strlist__delete(list);
269 
270 	pr_debug("Purged all: %s\n", err ? "FAIL" : "Ok");
271 	return err;
272 }
273 
274 static bool dso__missing_buildid_cache(struct dso *dso, int parm __maybe_unused)
275 {
276 	char filename[PATH_MAX];
277 	u8 build_id[BUILD_ID_SIZE];
278 
279 	if (dso__build_id_filename(dso, filename, sizeof(filename), false) &&
280 	    filename__read_build_id(filename, build_id,
281 				    sizeof(build_id)) != sizeof(build_id)) {
282 		if (errno == ENOENT)
283 			return false;
284 
285 		pr_warning("Problems with %s file, consider removing it from the cache\n",
286 			   filename);
287 	} else if (memcmp(dso->build_id, build_id, sizeof(dso->build_id))) {
288 		pr_warning("Problems with %s file, consider removing it from the cache\n",
289 			   filename);
290 	}
291 
292 	return true;
293 }
294 
295 static int build_id_cache__fprintf_missing(struct perf_session *session, FILE *fp)
296 {
297 	perf_session__fprintf_dsos_buildid(session, fp, dso__missing_buildid_cache, 0);
298 	return 0;
299 }
300 
301 static int build_id_cache__update_file(const char *filename, struct nsinfo *nsi)
302 {
303 	u8 build_id[BUILD_ID_SIZE];
304 	char sbuild_id[SBUILD_ID_SIZE];
305 	struct nscookie nsc;
306 
307 	int err;
308 
309 	nsinfo__mountns_enter(nsi, &nsc);
310 	err = filename__read_build_id(filename, &build_id, sizeof(build_id));
311 	nsinfo__mountns_exit(&nsc);
312 	if (err < 0) {
313 		pr_debug("Couldn't read a build-id in %s\n", filename);
314 		return -1;
315 	}
316 	err = 0;
317 
318 	build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
319 	if (build_id_cache__cached(sbuild_id))
320 		err = build_id_cache__remove_s(sbuild_id);
321 
322 	if (!err)
323 		err = build_id_cache__add_s(sbuild_id, filename, nsi, false,
324 					    false);
325 
326 	pr_debug("Updating %s %s: %s\n", sbuild_id, filename,
327 		 err ? "FAIL" : "Ok");
328 
329 	return err;
330 }
331 
332 static int build_id_cache__show_all(void)
333 {
334 	struct strlist *bidlist;
335 	struct str_node *nd;
336 	char *buf;
337 
338 	bidlist = build_id_cache__list_all(true);
339 	if (!bidlist) {
340 		pr_debug("Failed to get buildids: -%d\n", errno);
341 		return -1;
342 	}
343 	strlist__for_each_entry(nd, bidlist) {
344 		buf = build_id_cache__origname(nd->s);
345 		fprintf(stdout, "%s %s\n", nd->s, buf);
346 		free(buf);
347 	}
348 	strlist__delete(bidlist);
349 	return 0;
350 }
351 
352 int cmd_buildid_cache(int argc, const char **argv)
353 {
354 	struct strlist *list;
355 	struct str_node *pos;
356 	int ret = 0;
357 	int ns_id = -1;
358 	bool force = false;
359 	bool list_files = false;
360 	bool opts_flag = false;
361 	bool purge_all = false;
362 	char const *add_name_list_str = NULL,
363 		   *remove_name_list_str = NULL,
364 		   *purge_name_list_str = NULL,
365 		   *missing_filename = NULL,
366 		   *update_name_list_str = NULL,
367 		   *kcore_filename = NULL;
368 	char sbuf[STRERR_BUFSIZE];
369 
370 	struct perf_data data = {
371 		.mode  = PERF_DATA_MODE_READ,
372 	};
373 	struct perf_session *session = NULL;
374 	struct nsinfo *nsi = NULL;
375 
376 	const struct option buildid_cache_options[] = {
377 	OPT_STRING('a', "add", &add_name_list_str,
378 		   "file list", "file(s) to add"),
379 	OPT_STRING('k', "kcore", &kcore_filename,
380 		   "file", "kcore file to add"),
381 	OPT_STRING('r', "remove", &remove_name_list_str, "file list",
382 		    "file(s) to remove"),
383 	OPT_STRING('p', "purge", &purge_name_list_str, "file list",
384 		    "file(s) to remove (remove old caches too)"),
385 	OPT_BOOLEAN('P', "purge-all", &purge_all, "purge all cached files"),
386 	OPT_BOOLEAN('l', "list", &list_files, "list all cached files"),
387 	OPT_STRING('M', "missing", &missing_filename, "file",
388 		   "to find missing build ids in the cache"),
389 	OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
390 	OPT_STRING('u', "update", &update_name_list_str, "file list",
391 		    "file(s) to update"),
392 	OPT_INCR('v', "verbose", &verbose, "be more verbose"),
393 	OPT_INTEGER(0, "target-ns", &ns_id, "target pid for namespace context"),
394 	OPT_END()
395 	};
396 	const char * const buildid_cache_usage[] = {
397 		"perf buildid-cache [<options>]",
398 		NULL
399 	};
400 
401 	argc = parse_options(argc, argv, buildid_cache_options,
402 			     buildid_cache_usage, 0);
403 
404 	opts_flag = add_name_list_str || kcore_filename ||
405 		remove_name_list_str || purge_name_list_str ||
406 		missing_filename || update_name_list_str ||
407 		purge_all;
408 
409 	if (argc || !(list_files || opts_flag))
410 		usage_with_options(buildid_cache_usage, buildid_cache_options);
411 
412 	/* -l is exclusive. It can not be used with other options. */
413 	if (list_files && opts_flag) {
414 		usage_with_options_msg(buildid_cache_usage,
415 			buildid_cache_options, "-l is exclusive.\n");
416 	}
417 
418 	if (ns_id > 0)
419 		nsi = nsinfo__new(ns_id);
420 
421 	if (missing_filename) {
422 		data.path  = missing_filename;
423 		data.force = force;
424 
425 		session = perf_session__new(&data, false, NULL);
426 		if (IS_ERR(session))
427 			return PTR_ERR(session);
428 	}
429 
430 	if (symbol__init(session ? &session->header.env : NULL) < 0)
431 		goto out;
432 
433 	setup_pager();
434 
435 	if (list_files) {
436 		ret = build_id_cache__show_all();
437 		goto out;
438 	}
439 
440 	if (add_name_list_str) {
441 		list = strlist__new(add_name_list_str, NULL);
442 		if (list) {
443 			strlist__for_each_entry(pos, list)
444 				if (build_id_cache__add_file(pos->s, nsi)) {
445 					if (errno == EEXIST) {
446 						pr_debug("%s already in the cache\n",
447 							 pos->s);
448 						continue;
449 					}
450 					pr_warning("Couldn't add %s: %s\n",
451 						   pos->s, str_error_r(errno, sbuf, sizeof(sbuf)));
452 				}
453 
454 			strlist__delete(list);
455 		}
456 	}
457 
458 	if (remove_name_list_str) {
459 		list = strlist__new(remove_name_list_str, NULL);
460 		if (list) {
461 			strlist__for_each_entry(pos, list)
462 				if (build_id_cache__remove_file(pos->s, nsi)) {
463 					if (errno == ENOENT) {
464 						pr_debug("%s wasn't in the cache\n",
465 							 pos->s);
466 						continue;
467 					}
468 					pr_warning("Couldn't remove %s: %s\n",
469 						   pos->s, str_error_r(errno, sbuf, sizeof(sbuf)));
470 				}
471 
472 			strlist__delete(list);
473 		}
474 	}
475 
476 	if (purge_name_list_str) {
477 		list = strlist__new(purge_name_list_str, NULL);
478 		if (list) {
479 			strlist__for_each_entry(pos, list)
480 				if (build_id_cache__purge_path(pos->s, nsi)) {
481 					if (errno == ENOENT) {
482 						pr_debug("%s wasn't in the cache\n",
483 							 pos->s);
484 						continue;
485 					}
486 					pr_warning("Couldn't remove %s: %s\n",
487 						   pos->s, str_error_r(errno, sbuf, sizeof(sbuf)));
488 				}
489 
490 			strlist__delete(list);
491 		}
492 	}
493 
494 	if (purge_all) {
495 		if (build_id_cache__purge_all()) {
496 			pr_warning("Couldn't remove some caches. Error: %s.\n",
497 				str_error_r(errno, sbuf, sizeof(sbuf)));
498 		}
499 	}
500 
501 	if (missing_filename)
502 		ret = build_id_cache__fprintf_missing(session, stdout);
503 
504 	if (update_name_list_str) {
505 		list = strlist__new(update_name_list_str, NULL);
506 		if (list) {
507 			strlist__for_each_entry(pos, list)
508 				if (build_id_cache__update_file(pos->s, nsi)) {
509 					if (errno == ENOENT) {
510 						pr_debug("%s wasn't in the cache\n",
511 							 pos->s);
512 						continue;
513 					}
514 					pr_warning("Couldn't update %s: %s\n",
515 						   pos->s, str_error_r(errno, sbuf, sizeof(sbuf)));
516 				}
517 
518 			strlist__delete(list);
519 		}
520 	}
521 
522 	if (kcore_filename && build_id_cache__add_kcore(kcore_filename, force))
523 		pr_warning("Couldn't add %s\n", kcore_filename);
524 
525 out:
526 	perf_session__delete(session);
527 	nsinfo__zput(nsi);
528 
529 	return ret;
530 }
531