tools/perf/util/dsos.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include "debug.h"
   3 #include "dsos.h"
   4 #include "dso.h"
   5 #include "vdso.h"
   6 #include "namespaces.h"
   7 #include <libgen.h>
   8 #include <stdlib.h>
   9 #include <string.h>
  10 #include <symbol.h> // filename__read_build_id
  11
  12 static int __dso_id__cmp(struct dso_id *a, struct dso_id *b)
  13 {
  14         if (a->maj > b->maj) return -1;
  15         if (a->maj < b->maj) return 1;
  16
  17         if (a->min > b->min) return -1;
  18         if (a->min < b->min) return 1;
  19
  20         if (a->ino > b->ino) return -1;
  21         if (a->ino < b->ino) return 1;
  22
  23         if (a->ino_generation > b->ino_generation) return -1;
  24         if (a->ino_generation < b->ino_generation) return 1;
  25
  26         return 0;
  27 }
  28
  29 static bool dso_id__empty(struct dso_id *id)
  30 {
  31         if (!id)
  32                 return true;
  33
  34         return !id->maj && !id->min && !id->ino && !id->ino_generation;
  35 }
  36
  37 static void dso__inject_id(struct dso *dso, struct dso_id *id)
  38 {
  39         dso->id.maj = id->maj;
  40         dso->id.min = id->min;
  41         dso->id.ino = id->ino;
  42         dso->id.ino_generation = id->ino_generation;
  43 }
  44
  45 static int dso_id__cmp(struct dso_id *a, struct dso_id *b)
  46 {
  47         /*
  48          * The second is always dso->id, so zeroes if not set, assume passing
  49          * NULL for a means a zeroed id
  50          */
  51         if (dso_id__empty(a) || dso_id__empty(b))
  52                 return 0;
  53
  54         return __dso_id__cmp(a, b);
  55 }
  56
  57 int dso__cmp_id(struct dso *a, struct dso *b)
  58 {
  59         return __dso_id__cmp(&a->id, &b->id);
  60 }
  61
  62 bool __dsos__read_build_ids(struct list_head *head, bool with_hits)
  63 {
  64         bool have_build_id = false;
  65         struct dso *pos;
  66         struct nscookie nsc;
  67
  68         list_for_each_entry(pos, head, node) {
  69                 if (with_hits && !pos->hit && !dso__is_vdso(pos))
  70                         continue;
  71                 if (pos->has_build_id) {
  72                         have_build_id = true;
  73                         continue;
  74                 }
  75                 nsinfo__mountns_enter(pos->nsinfo, &nsc);
  76                 if (filename__read_build_id(pos->long_name, pos->build_id,
  77                                             sizeof(pos->build_id)) > 0) {
  78                         have_build_id     = true;
  79                         pos->has_build_id = true;
  80                 }
  81                 nsinfo__mountns_exit(&nsc);
  82         }
  83
  84         return have_build_id;
  85 }
  86
  87 static int __dso__cmp_long_name(const char *long_name, struct dso_id *id, struct dso *b)
  88 {
  89         int rc = strcmp(long_name, b->long_name);
  90         return rc ?: dso_id__cmp(id, &b->id);
  91 }
  92
  93 static int __dso__cmp_short_name(const char *short_name, struct dso_id *id, struct dso *b)
  94 {
  95         int rc = strcmp(short_name, b->short_name);
  96         return rc ?: dso_id__cmp(id, &b->id);
  97 }
  98
  99 static int dso__cmp_short_name(struct dso *a, struct dso *b)
 100 {
 101         return __dso__cmp_short_name(a->short_name, &a->id, b);
 102 }
 103
 104 /*
 105  * Find a matching entry and/or link current entry to RB tree.
 106  * Either one of the dso or name parameter must be non-NULL or the
 107  * function will not work.
 108  */
 109 struct dso *__dsos__findnew_link_by_longname_id(struct rb_root *root, struct dso *dso,
 110                                                 const char *name, struct dso_id *id)
 111 {
 112         struct rb_node **p = &root->rb_node;
 113         struct rb_node  *parent = NULL;
 114
 115         if (!name)
 116                 name = dso->long_name;
 117         /*
 118          * Find node with the matching name
 119          */
 120         while (*p) {
 121                 struct dso *this = rb_entry(*p, struct dso, rb_node);
 122                 int rc = __dso__cmp_long_name(name, id, this);
 123
 124                 parent = *p;
 125                 if (rc == 0) {
 126                         /*
 127                          * In case the new DSO is a duplicate of an existing
 128                          * one, print a one-time warning & put the new entry
 129                          * at the end of the list of duplicates.
 130                          */
 131                         if (!dso || (dso == this))
 132                                 return this;    /* Find matching dso */
 133                         /*
 134                          * The core kernel DSOs may have duplicated long name.
 135                          * In this case, the short name should be different.
 136                          * Comparing the short names to differentiate the DSOs.
 137                          */
 138                         rc = dso__cmp_short_name(dso, this);
 139                         if (rc == 0) {
 140                                 pr_err("Duplicated dso name: %s\n", name);
 141                                 return NULL;
 142                         }
 143                 }
 144                 if (rc < 0)
 145                         p = &parent->rb_left;
 146                 else
 147                         p = &parent->rb_right;
 148         }
 149         if (dso) {
 150                 /* Add new node and rebalance tree */
 151                 rb_link_node(&dso->rb_node, parent, p);
 152                 rb_insert_color(&dso->rb_node, root);
 153                 dso->root = root;
 154         }
 155         return NULL;
 156 }
 157
 158 void __dsos__add(struct dsos *dsos, struct dso *dso)
 159 {
 160         list_add_tail(&dso->node, &dsos->head);
 161         __dsos__findnew_link_by_longname_id(&dsos->root, dso, NULL, &dso->id);
 162         /*
 163          * It is now in the linked list, grab a reference, then garbage collect
 164          * this when needing memory, by looking at LRU dso instances in the
 165          * list with atomic_read(&dso->refcnt) == 1, i.e. no references
 166          * anywhere besides the one for the list, do, under a lock for the
 167          * list: remove it from the list, then a dso__put(), that probably will
 168          * be the last and will then call dso__delete(), end of life.
 169          *
 170          * That, or at the end of the 'struct machine' lifetime, when all
 171          * 'struct dso' instances will be removed from the list, in
 172          * dsos__exit(), if they have no other reference from some other data
 173          * structure.
 174          *
 175          * E.g.: after processing a 'perf.data' file and storing references
 176          * to objects instantiated while processing events, we will have
 177          * references to the 'thread', 'map', 'dso' structs all from 'struct
 178          * hist_entry' instances, but we may not need anything not referenced,
 179          * so we might as well call machines__exit()/machines__delete() and
 180          * garbage collect it.
 181          */
 182         dso__get(dso);
 183 }
 184
 185 void dsos__add(struct dsos *dsos, struct dso *dso)
 186 {
 187         down_write(&dsos->lock);
 188         __dsos__add(dsos, dso);
 189         up_write(&dsos->lock);
 190 }
 191
 192 static struct dso *__dsos__findnew_by_longname_id(struct rb_root *root, const char *name, struct dso_id *id)
 193 {
 194         return __dsos__findnew_link_by_longname_id(root, NULL, name, id);
 195 }
 196
 197 static struct dso *__dsos__find_id(struct dsos *dsos, const char *name, struct dso_id *id, bool cmp_short)
 198 {
 199         struct dso *pos;
 200
 201         if (cmp_short) {
 202                 list_for_each_entry(pos, &dsos->head, node)
 203                         if (__dso__cmp_short_name(name, id, pos) == 0)
 204                                 return pos;
 205                 return NULL;
 206         }
 207         return __dsos__findnew_by_longname_id(&dsos->root, name, id);
 208 }
 209
 210 struct dso *__dsos__find(struct dsos *dsos, const char *name, bool cmp_short)
 211 {
 212         return __dsos__find_id(dsos, name, NULL, cmp_short);
 213 }
 214
 215 static void dso__set_basename(struct dso *dso)
 216 {
 217         char *base, *lname;
 218         int tid;
 219
 220         if (sscanf(dso->long_name, "/tmp/perf-%d.map", &tid) == 1) {
 221                 if (asprintf(&base, "[JIT] tid %d", tid) < 0)
 222                         return;
 223         } else {
 224               /*
 225                * basename() may modify path buffer, so we must pass
 226                * a copy.
 227                */
 228                 lname = strdup(dso->long_name);
 229                 if (!lname)
 230                         return;
 231
 232                 /*
 233                  * basename() may return a pointer to internal
 234                  * storage which is reused in subsequent calls
 235                  * so copy the result.
 236                  */
 237                 base = strdup(basename(lname));
 238
 239                 free(lname);
 240
 241                 if (!base)
 242                         return;
 243         }
 244         dso__set_short_name(dso, base, true);
 245 }
 246
 247 static struct dso *__dsos__addnew_id(struct dsos *dsos, const char *name, struct dso_id *id)
 248 {
 249         struct dso *dso = dso__new_id(name, id);
 250
 251         if (dso != NULL) {
 252                 __dsos__add(dsos, dso);
 253                 dso__set_basename(dso);
 254                 /* Put dso here because __dsos_add already got it */
 255                 dso__put(dso);
 256         }
 257         return dso;
 258 }
 259
 260 struct dso *__dsos__addnew(struct dsos *dsos, const char *name)
 261 {
 262         return __dsos__addnew_id(dsos, name, NULL);
 263 }
 264
 265 static struct dso *__dsos__findnew_id(struct dsos *dsos, const char *name, struct dso_id *id)
 266 {
 267         struct dso *dso = __dsos__find_id(dsos, name, id, false);
 268
 269         if (dso && dso_id__empty(&dso->id) && !dso_id__empty(id))
 270                 dso__inject_id(dso, id);
 271
 272         return dso ? dso : __dsos__addnew_id(dsos, name, id);
 273 }
 274
 275 struct dso *dsos__findnew_id(struct dsos *dsos, const char *name, struct dso_id *id)
 276 {
 277         struct dso *dso;
 278         down_write(&dsos->lock);
 279         dso = dso__get(__dsos__findnew_id(dsos, name, id));
 280         up_write(&dsos->lock);
 281         return dso;
 282 }
 283
 284 size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp,
 285                                bool (skip)(struct dso *dso, int parm), int parm)
 286 {
 287         struct dso *pos;
 288         size_t ret = 0;
 289
 290         list_for_each_entry(pos, head, node) {
 291                 if (skip && skip(pos, parm))
 292                         continue;
 293                 ret += dso__fprintf_buildid(pos, fp);
 294                 ret += fprintf(fp, " %s\n", pos->long_name);
 295         }
 296         return ret;
 297 }
 298
 299 size_t __dsos__fprintf(struct list_head *head, FILE *fp)
 300 {
 301         struct dso *pos;
 302         size_t ret = 0;
 303
 304         list_for_each_entry(pos, head, node) {
 305                 ret += dso__fprintf(pos, fp);
 306         }
 307
 308         return ret;
 309 }