1 /*
2  * builtin-buildid-cache.c
3  *
4  * Builtin buildid-cache command: Manages build-id cache
5  *
6  * Copyright (C) 2010, Red Hat Inc.
7  * Copyright (C) 2010, Arnaldo Carvalho de Melo <acme@redhat.com>
8  */
9 #include <sys/types.h>
10 #include <sys/time.h>
11 #include <time.h>
12 #include <dirent.h>
13 #include <unistd.h>
14 #include "builtin.h"
15 #include "perf.h"
16 #include "util/cache.h"
17 #include "util/debug.h"
18 #include "util/header.h"
19 #include "util/parse-options.h"
20 #include "util/strlist.h"
21 #include "util/build-id.h"
22 #include "util/session.h"
23 #include "util/symbol.h"
24 
25 static int build_id_cache__kcore_buildid(const char *proc_dir, char *sbuildid)
26 {
27 	char root_dir[PATH_MAX];
28 	char notes[PATH_MAX];
29 	u8 build_id[BUILD_ID_SIZE];
30 	char *p;
31 
32 	strlcpy(root_dir, proc_dir, sizeof(root_dir));
33 
34 	p = strrchr(root_dir, '/');
35 	if (!p)
36 		return -1;
37 	*p = '\0';
38 
39 	scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
40 
41 	if (sysfs__read_build_id(notes, build_id, sizeof(build_id)))
42 		return -1;
43 
44 	build_id__sprintf(build_id, sizeof(build_id), sbuildid);
45 
46 	return 0;
47 }
48 
49 static int build_id_cache__kcore_dir(char *dir, size_t sz)
50 {
51 	struct timeval tv;
52 	struct tm tm;
53 	char dt[32];
54 
55 	if (gettimeofday(&tv, NULL) || !localtime_r(&tv.tv_sec, &tm))
56 		return -1;
57 
58 	if (!strftime(dt, sizeof(dt), "%Y%m%d%H%M%S", &tm))
59 		return -1;
60 
61 	scnprintf(dir, sz, "%s%02u", dt, (unsigned)tv.tv_usec / 10000);
62 
63 	return 0;
64 }
65 
66 static bool same_kallsyms_reloc(const char *from_dir, char *to_dir)
67 {
68 	char from[PATH_MAX];
69 	char to[PATH_MAX];
70 	const char *name;
71 	u64 addr1 = 0, addr2 = 0;
72 	int i;
73 
74 	scnprintf(from, sizeof(from), "%s/kallsyms", from_dir);
75 	scnprintf(to, sizeof(to), "%s/kallsyms", to_dir);
76 
77 	for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) {
78 		addr1 = kallsyms__get_function_start(from, name);
79 		if (addr1)
80 			break;
81 	}
82 
83 	if (name)
84 		addr2 = kallsyms__get_function_start(to, name);
85 
86 	return addr1 == addr2;
87 }
88 
89 static int build_id_cache__kcore_existing(const char *from_dir, char *to_dir,
90 					  size_t to_dir_sz)
91 {
92 	char from[PATH_MAX];
93 	char to[PATH_MAX];
94 	char to_subdir[PATH_MAX];
95 	struct dirent *dent;
96 	int ret = -1;
97 	DIR *d;
98 
99 	d = opendir(to_dir);
100 	if (!d)
101 		return -1;
102 
103 	scnprintf(from, sizeof(from), "%s/modules", from_dir);
104 
105 	while (1) {
106 		dent = readdir(d);
107 		if (!dent)
108 			break;
109 		if (dent->d_type != DT_DIR)
110 			continue;
111 		scnprintf(to, sizeof(to), "%s/%s/modules", to_dir,
112 			  dent->d_name);
113 		scnprintf(to_subdir, sizeof(to_subdir), "%s/%s",
114 			  to_dir, dent->d_name);
115 		if (!compare_proc_modules(from, to) &&
116 		    same_kallsyms_reloc(from_dir, to_subdir)) {
117 			strlcpy(to_dir, to_subdir, to_dir_sz);
118 			ret = 0;
119 			break;
120 		}
121 	}
122 
123 	closedir(d);
124 
125 	return ret;
126 }
127 
128 static int build_id_cache__add_kcore(const char *filename, const char *debugdir,
129 				     bool force)
130 {
131 	char dir[32], sbuildid[BUILD_ID_SIZE * 2 + 1];
132 	char from_dir[PATH_MAX], to_dir[PATH_MAX];
133 	char *p;
134 
135 	strlcpy(from_dir, filename, sizeof(from_dir));
136 
137 	p = strrchr(from_dir, '/');
138 	if (!p || strcmp(p + 1, "kcore"))
139 		return -1;
140 	*p = '\0';
141 
142 	if (build_id_cache__kcore_buildid(from_dir, sbuildid))
143 		return -1;
144 
145 	scnprintf(to_dir, sizeof(to_dir), "%s/[kernel.kcore]/%s",
146 		  debugdir, sbuildid);
147 
148 	if (!force &&
149 	    !build_id_cache__kcore_existing(from_dir, to_dir, sizeof(to_dir))) {
150 		pr_debug("same kcore found in %s\n", to_dir);
151 		return 0;
152 	}
153 
154 	if (build_id_cache__kcore_dir(dir, sizeof(dir)))
155 		return -1;
156 
157 	scnprintf(to_dir, sizeof(to_dir), "%s/[kernel.kcore]/%s/%s",
158 		  debugdir, sbuildid, dir);
159 
160 	if (mkdir_p(to_dir, 0755))
161 		return -1;
162 
163 	if (kcore_copy(from_dir, to_dir)) {
164 		/* Remove YYYYmmddHHMMSShh directory */
165 		if (!rmdir(to_dir)) {
166 			p = strrchr(to_dir, '/');
167 			if (p)
168 				*p = '\0';
169 			/* Try to remove buildid directory */
170 			if (!rmdir(to_dir)) {
171 				p = strrchr(to_dir, '/');
172 				if (p)
173 					*p = '\0';
174 				/* Try to remove [kernel.kcore] directory */
175 				rmdir(to_dir);
176 			}
177 		}
178 		return -1;
179 	}
180 
181 	pr_debug("kcore added to build-id cache directory %s\n", to_dir);
182 
183 	return 0;
184 }
185 
186 static int build_id_cache__add_file(const char *filename, const char *debugdir)
187 {
188 	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
189 	u8 build_id[BUILD_ID_SIZE];
190 	int err;
191 
192 	if (filename__read_build_id(filename, &build_id, sizeof(build_id)) < 0) {
193 		pr_debug("Couldn't read a build-id in %s\n", filename);
194 		return -1;
195 	}
196 
197 	build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
198 	err = build_id_cache__add_s(sbuild_id, debugdir, filename,
199 				    false, false);
200 	if (verbose)
201 		pr_info("Adding %s %s: %s\n", sbuild_id, filename,
202 			err ? "FAIL" : "Ok");
203 	return err;
204 }
205 
206 static int build_id_cache__remove_file(const char *filename,
207 				       const char *debugdir)
208 {
209 	u8 build_id[BUILD_ID_SIZE];
210 	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
211 
212 	int err;
213 
214 	if (filename__read_build_id(filename, &build_id, sizeof(build_id)) < 0) {
215 		pr_debug("Couldn't read a build-id in %s\n", filename);
216 		return -1;
217 	}
218 
219 	build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
220 	err = build_id_cache__remove_s(sbuild_id, debugdir);
221 	if (verbose)
222 		pr_info("Removing %s %s: %s\n", sbuild_id, filename,
223 			err ? "FAIL" : "Ok");
224 
225 	return err;
226 }
227 
228 static bool dso__missing_buildid_cache(struct dso *dso, int parm __maybe_unused)
229 {
230 	char filename[PATH_MAX];
231 	u8 build_id[BUILD_ID_SIZE];
232 
233 	if (dso__build_id_filename(dso, filename, sizeof(filename)) &&
234 	    filename__read_build_id(filename, build_id,
235 				    sizeof(build_id)) != sizeof(build_id)) {
236 		if (errno == ENOENT)
237 			return false;
238 
239 		pr_warning("Problems with %s file, consider removing it from the cache\n",
240 			   filename);
241 	} else if (memcmp(dso->build_id, build_id, sizeof(dso->build_id))) {
242 		pr_warning("Problems with %s file, consider removing it from the cache\n",
243 			   filename);
244 	}
245 
246 	return true;
247 }
248 
249 static int build_id_cache__fprintf_missing(struct perf_session *session, FILE *fp)
250 {
251 	perf_session__fprintf_dsos_buildid(session, fp, dso__missing_buildid_cache, 0);
252 	return 0;
253 }
254 
255 static int build_id_cache__update_file(const char *filename,
256 				       const char *debugdir)
257 {
258 	u8 build_id[BUILD_ID_SIZE];
259 	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
260 
261 	int err;
262 
263 	if (filename__read_build_id(filename, &build_id, sizeof(build_id)) < 0) {
264 		pr_debug("Couldn't read a build-id in %s\n", filename);
265 		return -1;
266 	}
267 
268 	build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
269 	err = build_id_cache__remove_s(sbuild_id, debugdir);
270 	if (!err) {
271 		err = build_id_cache__add_s(sbuild_id, debugdir, filename,
272 					    false, false);
273 	}
274 	if (verbose)
275 		pr_info("Updating %s %s: %s\n", sbuild_id, filename,
276 			err ? "FAIL" : "Ok");
277 
278 	return err;
279 }
280 
281 int cmd_buildid_cache(int argc, const char **argv,
282 		      const char *prefix __maybe_unused)
283 {
284 	struct strlist *list;
285 	struct str_node *pos;
286 	int ret = 0;
287 	bool force = false;
288 	char debugdir[PATH_MAX];
289 	char const *add_name_list_str = NULL,
290 		   *remove_name_list_str = NULL,
291 		   *missing_filename = NULL,
292 		   *update_name_list_str = NULL,
293 		   *kcore_filename;
294 	char sbuf[STRERR_BUFSIZE];
295 
296 	struct perf_data_file file = {
297 		.mode  = PERF_DATA_MODE_READ,
298 	};
299 	struct perf_session *session = NULL;
300 
301 	const struct option buildid_cache_options[] = {
302 	OPT_STRING('a', "add", &add_name_list_str,
303 		   "file list", "file(s) to add"),
304 	OPT_STRING('k', "kcore", &kcore_filename,
305 		   "file", "kcore file to add"),
306 	OPT_STRING('r', "remove", &remove_name_list_str, "file list",
307 		    "file(s) to remove"),
308 	OPT_STRING('M', "missing", &missing_filename, "file",
309 		   "to find missing build ids in the cache"),
310 	OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
311 	OPT_STRING('u', "update", &update_name_list_str, "file list",
312 		    "file(s) to update"),
313 	OPT_INCR('v', "verbose", &verbose, "be more verbose"),
314 	OPT_END()
315 	};
316 	const char * const buildid_cache_usage[] = {
317 		"perf buildid-cache [<options>]",
318 		NULL
319 	};
320 
321 	argc = parse_options(argc, argv, buildid_cache_options,
322 			     buildid_cache_usage, 0);
323 
324 	if (missing_filename) {
325 		file.path = missing_filename;
326 		file.force = force;
327 
328 		session = perf_session__new(&file, false, NULL);
329 		if (session == NULL)
330 			return -1;
331 	}
332 
333 	if (symbol__init(session ? &session->header.env : NULL) < 0)
334 		goto out;
335 
336 	setup_pager();
337 
338 	snprintf(debugdir, sizeof(debugdir), "%s", buildid_dir);
339 
340 	if (add_name_list_str) {
341 		list = strlist__new(true, add_name_list_str);
342 		if (list) {
343 			strlist__for_each(pos, list)
344 				if (build_id_cache__add_file(pos->s, debugdir)) {
345 					if (errno == EEXIST) {
346 						pr_debug("%s already in the cache\n",
347 							 pos->s);
348 						continue;
349 					}
350 					pr_warning("Couldn't add %s: %s\n",
351 						   pos->s, strerror_r(errno, sbuf, sizeof(sbuf)));
352 				}
353 
354 			strlist__delete(list);
355 		}
356 	}
357 
358 	if (remove_name_list_str) {
359 		list = strlist__new(true, remove_name_list_str);
360 		if (list) {
361 			strlist__for_each(pos, list)
362 				if (build_id_cache__remove_file(pos->s, debugdir)) {
363 					if (errno == ENOENT) {
364 						pr_debug("%s wasn't in the cache\n",
365 							 pos->s);
366 						continue;
367 					}
368 					pr_warning("Couldn't remove %s: %s\n",
369 						   pos->s, strerror_r(errno, sbuf, sizeof(sbuf)));
370 				}
371 
372 			strlist__delete(list);
373 		}
374 	}
375 
376 	if (missing_filename)
377 		ret = build_id_cache__fprintf_missing(session, stdout);
378 
379 	if (update_name_list_str) {
380 		list = strlist__new(true, update_name_list_str);
381 		if (list) {
382 			strlist__for_each(pos, list)
383 				if (build_id_cache__update_file(pos->s, debugdir)) {
384 					if (errno == ENOENT) {
385 						pr_debug("%s wasn't in the cache\n",
386 							 pos->s);
387 						continue;
388 					}
389 					pr_warning("Couldn't update %s: %s\n",
390 						   pos->s, strerror_r(errno, sbuf, sizeof(sbuf)));
391 				}
392 
393 			strlist__delete(list);
394 		}
395 	}
396 
397 	if (kcore_filename &&
398 	    build_id_cache__add_kcore(kcore_filename, debugdir, force))
399 		pr_warning("Couldn't add %s\n", kcore_filename);
400 
401 out:
402 	if (session)
403 		perf_session__delete(session);
404 
405 	return ret;
406 }
407