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
15static int __dso_id__cmp(struct dso_id *a, struct dso_id *b)
16{
17 if (a->maj > b->maj) return -1;
18 if (a->maj < b->maj) return 1;
19
20 if (a->min > b->min) return -1;
21 if (a->min < b->min) return 1;
22
23 if (a->ino > b->ino) return -1;
24 if (a->ino < b->ino) return 1;
25
26 /*
27 * Synthesized MMAP events have zero ino_generation, avoid comparing
28 * them with MMAP events with actual ino_generation.
29 *
30 * I found it harmful because the mismatch resulted in a new
31 * dso that did not have a build ID whereas the original dso did have a
32 * build ID. The build ID was essential because the object was not found
33 * otherwise. - Adrian
34 */
35 if (a->ino_generation && b->ino_generation) {
36 if (a->ino_generation > b->ino_generation) return -1;
37 if (a->ino_generation < b->ino_generation) return 1;
38 }
39
40 return 0;
41}
42
43static bool dso_id__empty(struct dso_id *id)
44{
45 if (!id)
46 return true;
47
48 return !id->maj && !id->min && !id->ino && !id->ino_generation;
49}
50
51static void dso__inject_id(struct dso *dso, struct dso_id *id)
52{
53 dso->id.maj = id->maj;
54 dso->id.min = id->min;
55 dso->id.ino = id->ino;
56 dso->id.ino_generation = id->ino_generation;
57}
58
59static int dso_id__cmp(struct dso_id *a, struct dso_id *b)
60{
61 /*
62 * The second is always dso->id, so zeroes if not set, assume passing
63 * NULL for a means a zeroed id
64 */
65 if (dso_id__empty(id: a) || dso_id__empty(id: b))
66 return 0;
67
68 return __dso_id__cmp(a, b);
69}
70
71int dso__cmp_id(struct dso *a, struct dso *b)
72{
73 return __dso_id__cmp(a: &a->id, b: &b->id);
74}
75
76bool __dsos__read_build_ids(struct list_head *head, bool with_hits)
77{
78 bool have_build_id = false;
79 struct dso *pos;
80 struct nscookie nsc;
81
82 list_for_each_entry(pos, head, node) {
83 if (with_hits && !pos->hit && !dso__is_vdso(dso: pos))
84 continue;
85 if (pos->has_build_id) {
86 have_build_id = true;
87 continue;
88 }
89 nsinfo__mountns_enter(nsi: pos->nsinfo, nc: &nsc);
90 if (filename__read_build_id(filename: pos->long_name, id: &pos->bid) > 0) {
91 have_build_id = true;
92 pos->has_build_id = true;
93 } else if (errno == ENOENT && pos->nsinfo) {
94 char *new_name = dso__filename_with_chroot(dso: pos, filename: pos->long_name);
95
96 if (new_name && filename__read_build_id(filename: new_name,
97 id: &pos->bid) > 0) {
98 have_build_id = true;
99 pos->has_build_id = true;
100 }
101 free(new_name);
102 }
103 nsinfo__mountns_exit(nc: &nsc);
104 }
105
106 return have_build_id;
107}
108
109static int __dso__cmp_long_name(const char *long_name, struct dso_id *id, struct dso *b)
110{
111 int rc = strcmp(long_name, b->long_name);
112 return rc ?: dso_id__cmp(a: id, b: &b->id);
113}
114
115static int __dso__cmp_short_name(const char *short_name, struct dso_id *id, struct dso *b)
116{
117 int rc = strcmp(short_name, b->short_name);
118 return rc ?: dso_id__cmp(a: id, b: &b->id);
119}
120
121static int dso__cmp_short_name(struct dso *a, struct dso *b)
122{
123 return __dso__cmp_short_name(short_name: a->short_name, id: &a->id, b);
124}
125
126/*
127 * Find a matching entry and/or link current entry to RB tree.
128 * Either one of the dso or name parameter must be non-NULL or the
129 * function will not work.
130 */
131struct dso *__dsos__findnew_link_by_longname_id(struct rb_root *root, struct dso *dso,
132 const char *name, struct dso_id *id)
133{
134 struct rb_node **p = &root->rb_node;
135 struct rb_node *parent = NULL;
136
137 if (!name)
138 name = dso->long_name;
139 /*
140 * Find node with the matching name
141 */
142 while (*p) {
143 struct dso *this = rb_entry(*p, struct dso, rb_node);
144 int rc = __dso__cmp_long_name(long_name: name, id, b: this);
145
146 parent = *p;
147 if (rc == 0) {
148 /*
149 * In case the new DSO is a duplicate of an existing
150 * one, print a one-time warning & put the new entry
151 * at the end of the list of duplicates.
152 */
153 if (!dso || (dso == this))
154 return this; /* Find matching dso */
155 /*
156 * The core kernel DSOs may have duplicated long name.
157 * In this case, the short name should be different.
158 * Comparing the short names to differentiate the DSOs.
159 */
160 rc = dso__cmp_short_name(a: dso, b: this);
161 if (rc == 0) {
162 pr_err("Duplicated dso name: %s\n", name);
163 return NULL;
164 }
165 }
166 if (rc < 0)
167 p = &parent->rb_left;
168 else
169 p = &parent->rb_right;
170 }
171 if (dso) {
172 /* Add new node and rebalance tree */
173 rb_link_node(node: &dso->rb_node, parent, rb_link: p);
174 rb_insert_color(&dso->rb_node, root);
175 dso->root = root;
176 }
177 return NULL;
178}
179
180void __dsos__add(struct dsos *dsos, struct dso *dso)
181{
182 list_add_tail(new: &dso->node, head: &dsos->head);
183 __dsos__findnew_link_by_longname_id(root: &dsos->root, dso, NULL, id: &dso->id);
184 /*
185 * It is now in the linked list, grab a reference, then garbage collect
186 * this when needing memory, by looking at LRU dso instances in the
187 * list with atomic_read(&dso->refcnt) == 1, i.e. no references
188 * anywhere besides the one for the list, do, under a lock for the
189 * list: remove it from the list, then a dso__put(), that probably will
190 * be the last and will then call dso__delete(), end of life.
191 *
192 * That, or at the end of the 'struct machine' lifetime, when all
193 * 'struct dso' instances will be removed from the list, in
194 * dsos__exit(), if they have no other reference from some other data
195 * structure.
196 *
197 * E.g.: after processing a 'perf.data' file and storing references
198 * to objects instantiated while processing events, we will have
199 * references to the 'thread', 'map', 'dso' structs all from 'struct
200 * hist_entry' instances, but we may not need anything not referenced,
201 * so we might as well call machines__exit()/machines__delete() and
202 * garbage collect it.
203 */
204 dso__get(dso);
205}
206
207void dsos__add(struct dsos *dsos, struct dso *dso)
208{
209 down_write(sem: &dsos->lock);
210 __dsos__add(dsos, dso);
211 up_write(sem: &dsos->lock);
212}
213
214static struct dso *__dsos__findnew_by_longname_id(struct rb_root *root, const char *name, struct dso_id *id)
215{
216 return __dsos__findnew_link_by_longname_id(root, NULL, name, id);
217}
218
219static struct dso *__dsos__find_id(struct dsos *dsos, const char *name, struct dso_id *id, bool cmp_short)
220{
221 struct dso *pos;
222
223 if (cmp_short) {
224 list_for_each_entry(pos, &dsos->head, node)
225 if (__dso__cmp_short_name(short_name: name, id, b: pos) == 0)
226 return pos;
227 return NULL;
228 }
229 return __dsos__findnew_by_longname_id(root: &dsos->root, name, id);
230}
231
232struct dso *__dsos__find(struct dsos *dsos, const char *name, bool cmp_short)
233{
234 return __dsos__find_id(dsos, name, NULL, cmp_short);
235}
236
237static void dso__set_basename(struct dso *dso)
238{
239 char *base, *lname;
240 int tid;
241
242 if (sscanf(dso->long_name, "/tmp/perf-%d.map", &tid) == 1) {
243 if (asprintf(&base, "[JIT] tid %d", tid) < 0)
244 return;
245 } else {
246 /*
247 * basename() may modify path buffer, so we must pass
248 * a copy.
249 */
250 lname = strdup(dso->long_name);
251 if (!lname)
252 return;
253
254 /*
255 * basename() may return a pointer to internal
256 * storage which is reused in subsequent calls
257 * so copy the result.
258 */
259 base = strdup(basename(lname));
260
261 free(lname);
262
263 if (!base)
264 return;
265 }
266 dso__set_short_name(dso, name: base, name_allocated: true);
267}
268
269static struct dso *__dsos__addnew_id(struct dsos *dsos, const char *name, struct dso_id *id)
270{
271 struct dso *dso = dso__new_id(name, id);
272
273 if (dso != NULL) {
274 __dsos__add(dsos, dso);
275 dso__set_basename(dso);
276 /* Put dso here because __dsos_add already got it */
277 dso__put(dso);
278 }
279 return dso;
280}
281
282struct dso *__dsos__addnew(struct dsos *dsos, const char *name)
283{
284 return __dsos__addnew_id(dsos, name, NULL);
285}
286
287static struct dso *__dsos__findnew_id(struct dsos *dsos, const char *name, struct dso_id *id)
288{
289 struct dso *dso = __dsos__find_id(dsos, name, id, cmp_short: false);
290
291 if (dso && dso_id__empty(id: &dso->id) && !dso_id__empty(id))
292 dso__inject_id(dso, id);
293
294 return dso ? dso : __dsos__addnew_id(dsos, name, id);
295}
296
297struct dso *dsos__findnew_id(struct dsos *dsos, const char *name, struct dso_id *id)
298{
299 struct dso *dso;
300 down_write(sem: &dsos->lock);
301 dso = dso__get(dso: __dsos__findnew_id(dsos, name, id));
302 up_write(sem: &dsos->lock);
303 return dso;
304}
305
306size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp,
307 bool (skip)(struct dso *dso, int parm), int parm)
308{
309 struct dso *pos;
310 size_t ret = 0;
311
312 list_for_each_entry(pos, head, node) {
313 char sbuild_id[SBUILD_ID_SIZE];
314
315 if (skip && skip(pos, parm))
316 continue;
317 build_id__sprintf(build_id: &pos->bid, bf: sbuild_id);
318 ret += fprintf(fp, "%-40s %s\n", sbuild_id, pos->long_name);
319 }
320 return ret;
321}
322
323size_t __dsos__fprintf(struct list_head *head, FILE *fp)
324{
325 struct dso *pos;
326 size_t ret = 0;
327
328 list_for_each_entry(pos, head, node) {
329 ret += dso__fprintf(pos, fp);
330 }
331
332 return ret;
333}
334

source code of linux/tools/perf/util/dsos.c