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 static 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 43 static 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 51 static 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 59 static 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(a) || dso_id__empty(b)) 66 return 0; 67 68 return __dso_id__cmp(a, b); 69 } 70 71 int dso__cmp_id(struct dso *a, struct dso *b) 72 { 73 return __dso_id__cmp(&a->id, &b->id); 74 } 75 76 bool __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(pos)) 84 continue; 85 if (pos->has_build_id) { 86 have_build_id = true; 87 continue; 88 } 89 nsinfo__mountns_enter(pos->nsinfo, &nsc); 90 if (filename__read_build_id(pos->long_name, &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(pos, pos->long_name); 95 96 if (new_name && filename__read_build_id(new_name, 97 &pos->bid) > 0) { 98 have_build_id = true; 99 pos->has_build_id = true; 100 } 101 free(new_name); 102 } 103 nsinfo__mountns_exit(&nsc); 104 } 105 106 return have_build_id; 107 } 108 109 static 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(id, &b->id); 113 } 114 115 static 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(id, &b->id); 119 } 120 121 static int dso__cmp_short_name(struct dso *a, struct dso *b) 122 { 123 return __dso__cmp_short_name(a->short_name, &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 */ 131 struct 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(name, id, 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(dso, 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(&dso->rb_node, parent, p); 174 rb_insert_color(&dso->rb_node, root); 175 dso->root = root; 176 } 177 return NULL; 178 } 179 180 void __dsos__add(struct dsos *dsos, struct dso *dso) 181 { 182 list_add_tail(&dso->node, &dsos->head); 183 __dsos__findnew_link_by_longname_id(&dsos->root, dso, NULL, &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 } 206 207 void dsos__add(struct dsos *dsos, struct dso *dso) 208 { 209 down_write(&dsos->lock); 210 __dsos__add(dsos, dso); 211 up_write(&dsos->lock); 212 } 213 214 static 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 } 218 219 static 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(name, id, pos) == 0) 226 return pos; 227 return NULL; 228 } 229 return __dsos__findnew_by_longname_id(&dsos->root, name, id); 230 } 231 232 struct dso *__dsos__find(struct dsos *dsos, const char *name, bool cmp_short) 233 { 234 return __dsos__find_id(dsos, name, NULL, cmp_short); 235 } 236 237 static 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, base, true); 267 } 268 269 static 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 } 281 282 struct dso *__dsos__addnew(struct dsos *dsos, const char *name) 283 { 284 return __dsos__addnew_id(dsos, name, NULL); 285 } 286 287 static 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, false); 290 291 if (dso && dso_id__empty(&dso->id) && !dso_id__empty(id)) 292 dso__inject_id(dso, id); 293 294 return dso ? dso : __dsos__addnew_id(dsos, name, id); 295 } 296 297 struct dso *dsos__findnew_id(struct dsos *dsos, const char *name, struct dso_id *id) 298 { 299 struct dso *dso; 300 down_write(&dsos->lock); 301 dso = dso__get(__dsos__findnew_id(dsos, name, id)); 302 up_write(&dsos->lock); 303 return dso; 304 } 305 306 size_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(&pos->bid, sbuild_id); 318 ret += fprintf(fp, "%-40s %s\n", sbuild_id, pos->long_name); 319 } 320 return ret; 321 } 322 323 size_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