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 = filename_with_chroot(pos->nsinfo->pid, 95 pos->long_name); 96 97 if (new_name && filename__read_build_id(new_name, 98 &pos->bid) > 0) { 99 have_build_id = true; 100 pos->has_build_id = true; 101 } 102 free(new_name); 103 } 104 nsinfo__mountns_exit(&nsc); 105 } 106 107 return have_build_id; 108 } 109 110 static int __dso__cmp_long_name(const char *long_name, struct dso_id *id, struct dso *b) 111 { 112 int rc = strcmp(long_name, b->long_name); 113 return rc ?: dso_id__cmp(id, &b->id); 114 } 115 116 static int __dso__cmp_short_name(const char *short_name, struct dso_id *id, struct dso *b) 117 { 118 int rc = strcmp(short_name, b->short_name); 119 return rc ?: dso_id__cmp(id, &b->id); 120 } 121 122 static int dso__cmp_short_name(struct dso *a, struct dso *b) 123 { 124 return __dso__cmp_short_name(a->short_name, &a->id, b); 125 } 126 127 /* 128 * Find a matching entry and/or link current entry to RB tree. 129 * Either one of the dso or name parameter must be non-NULL or the 130 * function will not work. 131 */ 132 struct dso *__dsos__findnew_link_by_longname_id(struct rb_root *root, struct dso *dso, 133 const char *name, struct dso_id *id) 134 { 135 struct rb_node **p = &root->rb_node; 136 struct rb_node *parent = NULL; 137 138 if (!name) 139 name = dso->long_name; 140 /* 141 * Find node with the matching name 142 */ 143 while (*p) { 144 struct dso *this = rb_entry(*p, struct dso, rb_node); 145 int rc = __dso__cmp_long_name(name, id, this); 146 147 parent = *p; 148 if (rc == 0) { 149 /* 150 * In case the new DSO is a duplicate of an existing 151 * one, print a one-time warning & put the new entry 152 * at the end of the list of duplicates. 153 */ 154 if (!dso || (dso == this)) 155 return this; /* Find matching dso */ 156 /* 157 * The core kernel DSOs may have duplicated long name. 158 * In this case, the short name should be different. 159 * Comparing the short names to differentiate the DSOs. 160 */ 161 rc = dso__cmp_short_name(dso, this); 162 if (rc == 0) { 163 pr_err("Duplicated dso name: %s\n", name); 164 return NULL; 165 } 166 } 167 if (rc < 0) 168 p = &parent->rb_left; 169 else 170 p = &parent->rb_right; 171 } 172 if (dso) { 173 /* Add new node and rebalance tree */ 174 rb_link_node(&dso->rb_node, parent, p); 175 rb_insert_color(&dso->rb_node, root); 176 dso->root = root; 177 } 178 return NULL; 179 } 180 181 void __dsos__add(struct dsos *dsos, struct dso *dso) 182 { 183 list_add_tail(&dso->node, &dsos->head); 184 __dsos__findnew_link_by_longname_id(&dsos->root, dso, NULL, &dso->id); 185 /* 186 * It is now in the linked list, grab a reference, then garbage collect 187 * this when needing memory, by looking at LRU dso instances in the 188 * list with atomic_read(&dso->refcnt) == 1, i.e. no references 189 * anywhere besides the one for the list, do, under a lock for the 190 * list: remove it from the list, then a dso__put(), that probably will 191 * be the last and will then call dso__delete(), end of life. 192 * 193 * That, or at the end of the 'struct machine' lifetime, when all 194 * 'struct dso' instances will be removed from the list, in 195 * dsos__exit(), if they have no other reference from some other data 196 * structure. 197 * 198 * E.g.: after processing a 'perf.data' file and storing references 199 * to objects instantiated while processing events, we will have 200 * references to the 'thread', 'map', 'dso' structs all from 'struct 201 * hist_entry' instances, but we may not need anything not referenced, 202 * so we might as well call machines__exit()/machines__delete() and 203 * garbage collect it. 204 */ 205 dso__get(dso); 206 } 207 208 void dsos__add(struct dsos *dsos, struct dso *dso) 209 { 210 down_write(&dsos->lock); 211 __dsos__add(dsos, dso); 212 up_write(&dsos->lock); 213 } 214 215 static struct dso *__dsos__findnew_by_longname_id(struct rb_root *root, const char *name, struct dso_id *id) 216 { 217 return __dsos__findnew_link_by_longname_id(root, NULL, name, id); 218 } 219 220 static struct dso *__dsos__find_id(struct dsos *dsos, const char *name, struct dso_id *id, bool cmp_short) 221 { 222 struct dso *pos; 223 224 if (cmp_short) { 225 list_for_each_entry(pos, &dsos->head, node) 226 if (__dso__cmp_short_name(name, id, pos) == 0) 227 return pos; 228 return NULL; 229 } 230 return __dsos__findnew_by_longname_id(&dsos->root, name, id); 231 } 232 233 struct dso *__dsos__find(struct dsos *dsos, const char *name, bool cmp_short) 234 { 235 return __dsos__find_id(dsos, name, NULL, cmp_short); 236 } 237 238 static void dso__set_basename(struct dso *dso) 239 { 240 char *base, *lname; 241 int tid; 242 243 if (sscanf(dso->long_name, "/tmp/perf-%d.map", &tid) == 1) { 244 if (asprintf(&base, "[JIT] tid %d", tid) < 0) 245 return; 246 } else { 247 /* 248 * basename() may modify path buffer, so we must pass 249 * a copy. 250 */ 251 lname = strdup(dso->long_name); 252 if (!lname) 253 return; 254 255 /* 256 * basename() may return a pointer to internal 257 * storage which is reused in subsequent calls 258 * so copy the result. 259 */ 260 base = strdup(basename(lname)); 261 262 free(lname); 263 264 if (!base) 265 return; 266 } 267 dso__set_short_name(dso, base, true); 268 } 269 270 static struct dso *__dsos__addnew_id(struct dsos *dsos, const char *name, struct dso_id *id) 271 { 272 struct dso *dso = dso__new_id(name, id); 273 274 if (dso != NULL) { 275 __dsos__add(dsos, dso); 276 dso__set_basename(dso); 277 /* Put dso here because __dsos_add already got it */ 278 dso__put(dso); 279 } 280 return dso; 281 } 282 283 struct dso *__dsos__addnew(struct dsos *dsos, const char *name) 284 { 285 return __dsos__addnew_id(dsos, name, NULL); 286 } 287 288 static struct dso *__dsos__findnew_id(struct dsos *dsos, const char *name, struct dso_id *id) 289 { 290 struct dso *dso = __dsos__find_id(dsos, name, id, false); 291 292 if (dso && dso_id__empty(&dso->id) && !dso_id__empty(id)) 293 dso__inject_id(dso, id); 294 295 return dso ? dso : __dsos__addnew_id(dsos, name, id); 296 } 297 298 struct dso *dsos__findnew_id(struct dsos *dsos, const char *name, struct dso_id *id) 299 { 300 struct dso *dso; 301 down_write(&dsos->lock); 302 dso = dso__get(__dsos__findnew_id(dsos, name, id)); 303 up_write(&dsos->lock); 304 return dso; 305 } 306 307 size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp, 308 bool (skip)(struct dso *dso, int parm), int parm) 309 { 310 struct dso *pos; 311 size_t ret = 0; 312 313 list_for_each_entry(pos, head, node) { 314 char sbuild_id[SBUILD_ID_SIZE]; 315 316 if (skip && skip(pos, parm)) 317 continue; 318 build_id__sprintf(&pos->bid, sbuild_id); 319 ret += fprintf(fp, "%-40s %s\n", sbuild_id, pos->long_name); 320 } 321 return ret; 322 } 323 324 size_t __dsos__fprintf(struct list_head *head, FILE *fp) 325 { 326 struct dso *pos; 327 size_t ret = 0; 328 329 list_for_each_entry(pos, head, node) { 330 ret += dso__fprintf(pos, fp); 331 } 332 333 return ret; 334 } 335