xref: /linux/tools/perf/util/dsos.c (revision 25489a4f556414445d342951615178368ee45cde)
1 // SPDX-License-Identifier: GPL-2.0
2 #include "debug.h"
3 #include "dsos.h"
4 #include "dso.h"
5 #include "util.h"
6 #include "vdso.h"
7 #include "namespaces.h"
8 #include <errno.h>
9 #include <libgen.h>
10 #include <stdlib.h>
11 #include <string.h>
12 #include <symbol.h> // filename__read_build_id
13 #include <unistd.h>
14 
15 void dsos__init(struct dsos *dsos)
16 {
17 	init_rwsem(&dsos->lock);
18 
19 	dsos->cnt = 0;
20 	dsos->allocated = 0;
21 	dsos->dsos = NULL;
22 	dsos->sorted = true;
23 }
24 
25 static void dsos__purge(struct dsos *dsos)
26 {
27 	down_write(&dsos->lock);
28 
29 	for (unsigned int i = 0; i < dsos->cnt; i++) {
30 		struct dso *dso = dsos->dsos[i];
31 
32 		dso__set_dsos(dso, NULL);
33 		dso__put(dso);
34 	}
35 
36 	zfree(&dsos->dsos);
37 	dsos->cnt = 0;
38 	dsos->allocated = 0;
39 	dsos->sorted = true;
40 
41 	up_write(&dsos->lock);
42 }
43 
44 void dsos__exit(struct dsos *dsos)
45 {
46 	dsos__purge(dsos);
47 	exit_rwsem(&dsos->lock);
48 }
49 
50 
51 static int __dsos__for_each_dso(struct dsos *dsos,
52 				int (*cb)(struct dso *dso, void *data),
53 				void *data)
54 {
55 	for (unsigned int i = 0; i < dsos->cnt; i++) {
56 		struct dso *dso = dsos->dsos[i];
57 		int err;
58 
59 		err = cb(dso, data);
60 		if (err)
61 			return err;
62 	}
63 	return 0;
64 }
65 
66 struct dsos__read_build_ids_cb_args {
67 	bool with_hits;
68 	bool have_build_id;
69 };
70 
71 static int dsos__read_build_ids_cb(struct dso *dso, void *data)
72 {
73 	struct dsos__read_build_ids_cb_args *args = data;
74 	struct nscookie nsc;
75 
76 	if (args->with_hits && !dso__hit(dso) && !dso__is_vdso(dso))
77 		return 0;
78 	if (dso__has_build_id(dso)) {
79 		args->have_build_id = true;
80 		return 0;
81 	}
82 	nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);
83 	if (filename__read_build_id(dso__long_name(dso), dso__bid(dso)) > 0) {
84 		args->have_build_id = true;
85 		dso__set_has_build_id(dso);
86 	} else if (errno == ENOENT && dso__nsinfo(dso)) {
87 		char *new_name = dso__filename_with_chroot(dso, dso__long_name(dso));
88 
89 		if (new_name && filename__read_build_id(new_name, dso__bid(dso)) > 0) {
90 			args->have_build_id = true;
91 			dso__set_has_build_id(dso);
92 		}
93 		free(new_name);
94 	}
95 	nsinfo__mountns_exit(&nsc);
96 	return 0;
97 }
98 
99 bool dsos__read_build_ids(struct dsos *dsos, bool with_hits)
100 {
101 	struct dsos__read_build_ids_cb_args args = {
102 		.with_hits = with_hits,
103 		.have_build_id = false,
104 	};
105 
106 	dsos__for_each_dso(dsos, dsos__read_build_ids_cb, &args);
107 	return args.have_build_id;
108 }
109 
110 static int __dso__cmp_long_name(const char *long_name, const struct dso_id *id,
111 				const struct dso *b)
112 {
113 	int rc = strcmp(long_name, dso__long_name(b));
114 	return rc ?: dso_id__cmp(id, dso__id_const(b));
115 }
116 
117 static int __dso__cmp_short_name(const char *short_name, const struct dso_id *id,
118 				 const struct dso *b)
119 {
120 	int rc = strcmp(short_name, dso__short_name(b));
121 	return rc ?: dso_id__cmp(id, dso__id_const(b));
122 }
123 
124 static int dsos__cmp_long_name_id_short_name(const void *va, const void *vb)
125 {
126 	const struct dso *a = *((const struct dso **)va);
127 	const struct dso *b = *((const struct dso **)vb);
128 	int rc = strcmp(dso__long_name(a), dso__long_name(b));
129 
130 	if (!rc) {
131 		rc = dso_id__cmp(dso__id_const(a), dso__id_const(b));
132 		if (!rc)
133 			rc = strcmp(dso__short_name(a), dso__short_name(b));
134 	}
135 	return rc;
136 }
137 
138 struct dsos__key {
139 	const char *long_name;
140 	const struct dso_id *id;
141 };
142 
143 static int dsos__cmp_key_long_name_id(const void *vkey, const void *vdso)
144 {
145 	const struct dsos__key *key = vkey;
146 	const struct dso *dso = *((const struct dso **)vdso);
147 
148 	return __dso__cmp_long_name(key->long_name, key->id, dso);
149 }
150 
151 /*
152  * Find a matching entry and/or link current entry to RB tree.
153  * Either one of the dso or name parameter must be non-NULL or the
154  * function will not work.
155  */
156 static struct dso *__dsos__find_by_longname_id(struct dsos *dsos,
157 					       const char *name,
158 					       const struct dso_id *id,
159 					       bool write_locked)
160 	SHARED_LOCKS_REQUIRED(dsos->lock)
161 {
162 	struct dsos__key key = {
163 		.long_name = name,
164 		.id = id,
165 	};
166 	struct dso **res;
167 
168 	if (dsos->dsos == NULL)
169 		return NULL;
170 
171 	if (!dsos->sorted) {
172 		if (!write_locked) {
173 			struct dso *dso;
174 
175 			up_read(&dsos->lock);
176 			down_write(&dsos->lock);
177 			dso = __dsos__find_by_longname_id(dsos, name, id,
178 							  /*write_locked=*/true);
179 			up_write(&dsos->lock);
180 			down_read(&dsos->lock);
181 			return dso;
182 		}
183 		qsort(dsos->dsos, dsos->cnt, sizeof(struct dso *),
184 		      dsos__cmp_long_name_id_short_name);
185 		dsos->sorted = true;
186 	}
187 
188 	res = bsearch(&key, dsos->dsos, dsos->cnt, sizeof(struct dso *),
189 		      dsos__cmp_key_long_name_id);
190 	if (!res)
191 		return NULL;
192 
193 	return dso__get(*res);
194 }
195 
196 int __dsos__add(struct dsos *dsos, struct dso *dso)
197 {
198 	if (dsos->cnt == dsos->allocated) {
199 		unsigned int to_allocate = 2;
200 		struct dso **temp;
201 
202 		if (dsos->allocated > 0)
203 			to_allocate = dsos->allocated * 2;
204 		temp = realloc(dsos->dsos, sizeof(struct dso *) * to_allocate);
205 		if (!temp)
206 			return -ENOMEM;
207 		dsos->dsos = temp;
208 		dsos->allocated = to_allocate;
209 	}
210 	if (!dsos->sorted) {
211 		dsos->dsos[dsos->cnt++] = dso__get(dso);
212 	} else {
213 		int low = 0, high = dsos->cnt - 1;
214 		int insert = dsos->cnt; /* Default to inserting at the end. */
215 
216 		while (low <= high) {
217 			int mid = low + (high - low) / 2;
218 			int cmp = dsos__cmp_long_name_id_short_name(&dsos->dsos[mid], &dso);
219 
220 			if (cmp < 0) {
221 				low = mid + 1;
222 			} else {
223 				high = mid - 1;
224 				insert = mid;
225 			}
226 		}
227 		memmove(&dsos->dsos[insert + 1], &dsos->dsos[insert],
228 			(dsos->cnt - insert) * sizeof(struct dso *));
229 		dsos->cnt++;
230 		dsos->dsos[insert] = dso__get(dso);
231 	}
232 	dso__set_dsos(dso, dsos);
233 	return 0;
234 }
235 
236 int dsos__add(struct dsos *dsos, struct dso *dso)
237 {
238 	int ret;
239 
240 	down_write(&dsos->lock);
241 	ret = __dsos__add(dsos, dso);
242 	up_write(&dsos->lock);
243 	return ret;
244 }
245 
246 struct dsos__find_id_cb_args {
247 	const char *name;
248 	const struct dso_id *id;
249 	struct dso *res;
250 };
251 
252 static int dsos__find_id_cb(struct dso *dso, void *data)
253 {
254 	struct dsos__find_id_cb_args *args = data;
255 
256 	if (__dso__cmp_short_name(args->name, args->id, dso) == 0) {
257 		args->res = dso__get(dso);
258 		return 1;
259 	}
260 	return 0;
261 
262 }
263 
264 static struct dso *__dsos__find_id(struct dsos *dsos, const char *name, const struct dso_id *id,
265 				   bool cmp_short, bool write_locked)
266 	SHARED_LOCKS_REQUIRED(dsos->lock)
267 {
268 	struct dso *res;
269 
270 	if (cmp_short) {
271 		struct dsos__find_id_cb_args args = {
272 			.name = name,
273 			.id = id,
274 			.res = NULL,
275 		};
276 
277 		__dsos__for_each_dso(dsos, dsos__find_id_cb, &args);
278 		return args.res;
279 	}
280 	res = __dsos__find_by_longname_id(dsos, name, id, write_locked);
281 	return res;
282 }
283 
284 struct dso *dsos__find(struct dsos *dsos, const char *name, bool cmp_short)
285 {
286 	struct dso *res;
287 
288 	down_read(&dsos->lock);
289 	res = __dsos__find_id(dsos, name, NULL, cmp_short, /*write_locked=*/false);
290 	up_read(&dsos->lock);
291 	return res;
292 }
293 
294 static void dso__set_basename(struct dso *dso)
295 {
296 	char *base, *lname;
297 	int tid;
298 
299 	if (perf_pid_map_tid(dso__long_name(dso), &tid)) {
300 		if (asprintf(&base, "[JIT] tid %d", tid) < 0)
301 			return;
302 	} else {
303 	      /*
304 	       * basename() may modify path buffer, so we must pass
305                * a copy.
306                */
307 		lname = strdup(dso__long_name(dso));
308 		if (!lname)
309 			return;
310 
311 		/*
312 		 * basename() may return a pointer to internal
313 		 * storage which is reused in subsequent calls
314 		 * so copy the result.
315 		 */
316 		base = strdup(basename(lname));
317 
318 		free(lname);
319 
320 		if (!base)
321 			return;
322 	}
323 	dso__set_short_name(dso, base, true);
324 }
325 
326 static struct dso *__dsos__addnew_id(struct dsos *dsos, const char *name, const struct dso_id *id)
327 {
328 	struct dso *dso = dso__new_id(name, id);
329 
330 	if (dso != NULL) {
331 		/*
332 		 * The dsos lock is held on entry, so rename the dso before
333 		 * adding it to avoid needing to take the dsos lock again to say
334 		 * the array isn't sorted.
335 		 */
336 		dso__set_basename(dso);
337 		__dsos__add(dsos, dso);
338 	}
339 	return dso;
340 }
341 
342 static struct dso *__dsos__findnew_id(struct dsos *dsos, const char *name, const struct dso_id *id)
343 	SHARED_LOCKS_REQUIRED(dsos->lock)
344 {
345 	struct dso *dso = __dsos__find_id(dsos, name, id, false, /*write_locked=*/true);
346 
347 	if (dso && dso_id__empty(dso__id(dso)) && !dso_id__empty(id))
348 		__dso__inject_id(dso, id);
349 
350 	return dso ? dso : __dsos__addnew_id(dsos, name, id);
351 }
352 
353 struct dso *dsos__findnew_id(struct dsos *dsos, const char *name, const struct dso_id *id)
354 {
355 	struct dso *dso;
356 	down_write(&dsos->lock);
357 	dso = __dsos__findnew_id(dsos, name, id);
358 	up_write(&dsos->lock);
359 	return dso;
360 }
361 
362 struct dsos__fprintf_buildid_cb_args {
363 	FILE *fp;
364 	bool (*skip)(struct dso *dso, int parm);
365 	int parm;
366 	size_t ret;
367 };
368 
369 static int dsos__fprintf_buildid_cb(struct dso *dso, void *data)
370 {
371 	struct dsos__fprintf_buildid_cb_args *args = data;
372 	char sbuild_id[SBUILD_ID_SIZE];
373 
374 	if (args->skip && args->skip(dso, args->parm))
375 		return 0;
376 	build_id__sprintf(dso__bid(dso), sbuild_id);
377 	args->ret += fprintf(args->fp, "%-40s %s\n", sbuild_id, dso__long_name(dso));
378 	return 0;
379 }
380 
381 size_t dsos__fprintf_buildid(struct dsos *dsos, FILE *fp,
382 			       bool (*skip)(struct dso *dso, int parm), int parm)
383 {
384 	struct dsos__fprintf_buildid_cb_args args = {
385 		.fp = fp,
386 		.skip = skip,
387 		.parm = parm,
388 		.ret = 0,
389 	};
390 
391 	dsos__for_each_dso(dsos, dsos__fprintf_buildid_cb, &args);
392 	return args.ret;
393 }
394 
395 struct dsos__fprintf_cb_args {
396 	FILE *fp;
397 	size_t ret;
398 };
399 
400 static int dsos__fprintf_cb(struct dso *dso, void *data)
401 {
402 	struct dsos__fprintf_cb_args *args = data;
403 
404 	args->ret += dso__fprintf(dso, args->fp);
405 	return 0;
406 }
407 
408 size_t dsos__fprintf(struct dsos *dsos, FILE *fp)
409 {
410 	struct dsos__fprintf_cb_args args = {
411 		.fp = fp,
412 		.ret = 0,
413 	};
414 
415 	dsos__for_each_dso(dsos, dsos__fprintf_cb, &args);
416 	return args.ret;
417 }
418 
419 static int dsos__hit_all_cb(struct dso *dso, void *data __maybe_unused)
420 {
421 	dso__set_hit(dso);
422 	return 0;
423 }
424 
425 int dsos__hit_all(struct dsos *dsos)
426 {
427 	return dsos__for_each_dso(dsos, dsos__hit_all_cb, NULL);
428 }
429 
430 struct dso *dsos__findnew_module_dso(struct dsos *dsos,
431 				     struct machine *machine,
432 				     struct kmod_path *m,
433 				     const char *filename)
434 {
435 	struct dso *dso;
436 
437 	down_write(&dsos->lock);
438 
439 	dso = __dsos__find_id(dsos, m->name, NULL, /*cmp_short=*/true, /*write_locked=*/true);
440 	if (dso) {
441 		up_write(&dsos->lock);
442 		return dso;
443 	}
444 	/*
445 	 * Failed to find the dso so create it. Change the name before adding it
446 	 * to the array, to avoid unnecessary sorts and potential locking
447 	 * issues.
448 	 */
449 	dso = dso__new_id(m->name, /*id=*/NULL);
450 	if (!dso) {
451 		up_write(&dsos->lock);
452 		return NULL;
453 	}
454 	dso__set_basename(dso);
455 	dso__set_module_info(dso, m, machine);
456 	dso__set_long_name(dso,	strdup(filename), true);
457 	dso__set_kernel(dso, DSO_SPACE__KERNEL);
458 	__dsos__add(dsos, dso);
459 
460 	up_write(&dsos->lock);
461 	return dso;
462 }
463 
464 static int dsos__find_kernel_dso_cb(struct dso *dso, void *data)
465 {
466 	struct dso **res = data;
467 	/*
468 	 * The cpumode passed to is_kernel_module is not the cpumode of *this*
469 	 * event. If we insist on passing correct cpumode to is_kernel_module,
470 	 * we should record the cpumode when we adding this dso to the linked
471 	 * list.
472 	 *
473 	 * However we don't really need passing correct cpumode.  We know the
474 	 * correct cpumode must be kernel mode (if not, we should not link it
475 	 * onto kernel_dsos list).
476 	 *
477 	 * Therefore, we pass PERF_RECORD_MISC_CPUMODE_UNKNOWN.
478 	 * is_kernel_module() treats it as a kernel cpumode.
479 	 */
480 	if (!dso__kernel(dso) ||
481 	    is_kernel_module(dso__long_name(dso), PERF_RECORD_MISC_CPUMODE_UNKNOWN))
482 		return 0;
483 
484 	*res = dso__get(dso);
485 	return 1;
486 }
487 
488 struct dso *dsos__find_kernel_dso(struct dsos *dsos)
489 {
490 	struct dso *res = NULL;
491 
492 	dsos__for_each_dso(dsos, dsos__find_kernel_dso_cb, &res);
493 	return res;
494 }
495 
496 int dsos__for_each_dso(struct dsos *dsos, int (*cb)(struct dso *dso, void *data), void *data)
497 {
498 	int err;
499 
500 	down_read(&dsos->lock);
501 	err = __dsos__for_each_dso(dsos, cb, data);
502 	up_read(&dsos->lock);
503 	return err;
504 }
505