git.itanic.dy.fi Git - scan-pagemap/blob - parse.c

   1 #include <sys/types.h>
   2 #include <dirent.h>
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include <string.h>
   6 #include <errno.h>
   7 #include <libgen.h>
   8
   9 #include "parse.h"
  10 #include "pagemap.h"
  11
  12 static struct maps_list *alloc_maplist(void)
  13 {
  14         struct maps_list *map;
  15
  16         map = malloc(sizeof *map);
  17         if (map == NULL)
  18                 goto err;
  19
  20         memset(map, 0, sizeof(*map));
  21         INIT_LIST_HEAD(&map->list);
  22 err:
  23         return map;
  24 }
  25
  26 static struct maps *alloc_map(void)
  27 {
  28         struct maps *map;
  29
  30         map = malloc(sizeof *map);
  31         if (map == NULL)
  32                 goto err;
  33
  34         memset(map, 0, sizeof(*map));
  35         INIT_LIST_HEAD(&map->list);
  36 err:
  37         return map;
  38 }
  39
  40 static struct maps *parse_maps(FILE *file, int pid, int tid)
  41 {
  42         struct maps *the_map = NULL;
  43         char line[1024];
  44         int ret;
  45
  46         while (fgets(line, sizeof(line), file)) {
  47                 struct maps *map = alloc_map();
  48                 unsigned long start, end;
  49                 char name[1024];
  50
  51                 if (map == NULL)
  52                         return 0;
  53
  54                 if (the_map == NULL)
  55                         the_map = map;
  56
  57                 ret = sscanf(line, "%lx-%lx %*s %*s %*s %*s %s",
  58                              &start, &end, name);
  59
  60                 if (ret < 2) {
  61                         printf("Error reading input: %s\n", line);
  62                         break;
  63                 }
  64
  65                 map->start = start;
  66                 map->end = end;
  67                 map->size = end - start;
  68                 map->pid = pid;
  69                 map->tid = tid;
  70
  71                 if (ret >= 3)
  72                         strncpy(map->name, name, sizeof(map->name));
  73
  74                 list_add_tail(&map->list, &the_map->list);
  75         }
  76
  77         return the_map;
  78 }
  79
  80 static void clear_pageframe(struct pageframe *pf)
  81 {
  82         memset(pf, 0, sizeof(*pf));
  83 }
  84
  85 static struct pageframe *alloc_pageframe(void)
  86 {
  87         struct pageframe *pageframe;
  88
  89         pageframe = malloc(sizeof *pageframe);
  90         if (pageframe == NULL)
  91                 goto err;
  92
  93         clear_pageframe(pageframe);
  94 err:
  95         return pageframe;
  96 }
  97
  98 #define BITRANGE(first, last) (((2ll << (last - first)) - 1) << first)
  99
 100 static void pageframe_to_struct(unsigned long long p, struct pageframe *pf)
 101 {
 102         /* Refer Documentation/vm/pagemap.txt for the format */
 103         pf->page_present = !!(BITRANGE(63, 63) & p);
 104         pf->page_swapped = !!(BITRANGE(62, 62) & p);
 105         pf->page_shift   =   (BITRANGE(55, 60) & p) >> 55;
 106         pf->pfn          =   (BITRANGE(0, 54) & p);
 107         pf->swap_type    =   (BITRANGE(0, 4) & p);
 108         pf->swap_offset  =   (BITRANGE(5, 54) & p) >> 5;
 109 #if 0
 110         printf("pfn: %lx shift: %d present: %d swapped %d\n",
 111                 pf->pfn, pf->page_shift, pf->page_present, pf->page_swapped);
 112 #endif
 113 }
 114
 115 static int compare_pageframe(struct bintree *at, struct bintree *bt)
 116 {
 117         struct pageframe *a, *b;
 118         a = tree_to_pageframe(at);
 119         b = tree_to_pageframe(bt);
 120
 121         return a->pfn - b->pfn;
 122 }
 123
 124 struct bintree_ops pageframe_ops = {
 125         .compare = compare_pageframe,
 126 };
 127
 128 static int read_cmdline(int pid, int tid, char *cmdline, size_t len)
 129 {
 130         FILE *file;
 131         char path[512];
 132         int ret;
 133
 134         snprintf(path, sizeof(path), "/proc/%d/task/%d/cmdline", pid, tid);
 135         file = fopen(path, "rb");
 136
 137         if (!file)
 138                 return -1;
 139
 140         ret = fread(cmdline, 1, len, file);
 141         if (ret > 0)
 142                 cmdline[ret - 1] = 0;
 143         fclose(file);
 144
 145         return ret > 0 ? 0 : -1;
 146 }
 147
 148 static char *get_name_by_pid(int pid)
 149 {
 150         static int last_pid;
 151         static char cmdline[128];
 152         static char *bname;
 153
 154         if (last_pid == pid)
 155                 return bname;
 156
 157         if (read_cmdline(pid, pid, cmdline, sizeof(cmdline))) {
 158                 bname = NULL;
 159                 return NULL;
 160         }
 161
 162         bname = basename(cmdline);
 163
 164         last_pid = pid;
 165         return bname;
 166 }
 167
 168 static int check_parse_opts(struct parse_opts *opts, struct pageframe *pf,
 169                 struct maps *map)
 170 {
 171         if (opts->parse_mask & PARSE_PID) {
 172                 if (opts->pid == map->pid)
 173                         return 1;
 174         }
 175
 176         if (opts->parse_mask & PARSE_MAP_NAME) {
 177                 if (!strcmp(opts->name, map->name))
 178                         return 1;
 179         }
 180
 181         if (opts->parse_mask & PARSE_PROCESS_NAME) {
 182                 if (!strcmp(opts->name, get_name_by_pid(map->pid)))
 183                         return 1;
 184         }
 185
 186         return 0;
 187 }
 188
 189 /* Read data from the /proc/pid/pagemap file */
 190 static int parse_pageframe(FILE *file, struct pageframe *pf_tree,
 191                         struct maps *maps, struct parse_opts *opts)
 192 {
 193         struct maps *map;
 194         struct maps_list *tmp;
 195         struct pageframe *match, *pageframe = NULL;
 196         long start, len, i;
 197         unsigned long long pf[10240];
 198         int ret, error;
 199
 200         if (maps == NULL)
 201                 return 0;
 202
 203         /* Go through the list of allocated memory areas */
 204         list_for_each_entry(map, &maps->list, list) {
 205                 start = map->start >> (PAGE_SHIFT - 3);
 206                 len = map->size >> (PAGE_SHIFT);
 207
 208                 ret = fseek(file, start, SEEK_SET);
 209                 if (ret) {
 210                         error = errno;
 211                         fprintf(stderr, "Error seeking to %lx: %s\n", start,
 212                                 strerror(error));
 213                         continue;
 214                 }
 215
 216                 for (i = 0; i < len; i++) {
 217                         if (!ret) {
 218                                 ret = fread(&pf, 1,
 219                                         MIN(sizeof(pf), (len - i) * 8), file);
 220                         }
 221                         if (ret < 0) {
 222                                 error = errno;
 223                                 continue;
 224                         }
 225                         if (!pageframe)
 226                                 pageframe = alloc_pageframe();
 227                         ret -= sizeof(pf[0]);
 228
 229                         /* ignore unused pages */
 230                         if (!pf[ret / sizeof(pf[0])])
 231                                 continue;
 232
 233                         pageframe_to_struct(pf[ret / sizeof(pf[0])], pageframe);
 234
 235                         /* ignore unused pages */
 236                         if (!(pageframe->page_swapped ||
 237                                         pageframe->page_present))
 238                                 continue;
 239
 240                         if (check_parse_opts(opts, pageframe, map)) {
 241                                 match = tree_to_pageframe(
 242                                         bintree_add(&pf_tree->tree,
 243                                                 &pageframe->tree,
 244                                                 &pageframe_ops));
 245                         } else {
 246                                 match = tree_to_pageframe(
 247                                         bintree_find(&pf_tree->tree,
 248                                                 &pageframe->tree,
 249                                                 &pageframe_ops));
 250                         }
 251
 252                         if (match == NULL)
 253                                 continue;
 254
 255                         if (match == pageframe)
 256                                 pageframe = NULL;
 257
 258                         match->refcount++;
 259                         /*
 260                          * Add a link from the physical page to this
 261                          * process's page map
 262                          */
 263                         if (!match->ml) {
 264                                 match->ml = alloc_maplist();
 265                                 match->ml->map = map;
 266                         } else {
 267                                 tmp = alloc_maplist();
 268                                 tmp->map = map;
 269                                 list_add(&tmp->list, &match->ml->list);
 270                         }
 271
 272                         if (match->page_present)
 273                                 map->pages_present++;
 274                         else if (match->page_swapped)
 275                                 map->pages_swapped++;
 276                 }
 277         }
 278
 279         return 0;
 280 }
 281
 282 static int read_pageframe(int pid, int tid, struct pageframe *pageframe,
 283                         struct process **process_list, struct parse_opts *opts)
 284 {
 285         struct maps *maps;
 286         struct process *process;
 287         FILE *file;
 288         char path[512];
 289
 290         process = malloc(sizeof(*process));
 291         memset(process, 0, sizeof(*process));
 292         INIT_LIST_HEAD(&process->list);
 293
 294         if (*process_list == NULL)
 295                 *process_list = process;
 296
 297         process->pid = pid;
 298         process->tid = tid;
 299
 300
 301         snprintf(path, sizeof(path), "/proc/%d/task/%d/maps", pid, tid);
 302         file = fopen(path, "rb");
 303
 304         if (!file)
 305                 goto free;
 306
 307         maps = parse_maps(file, pid, tid);
 308         fclose(file);
 309         process->maps = maps;
 310
 311         snprintf(path, sizeof(path), "/proc/%d/task/%d/pagemap", pid, tid);
 312         file = fopen(path, "rb");
 313
 314         if (!file)
 315                 goto free;
 316
 317         parse_pageframe(file, pageframe, maps, opts);
 318         fclose(file);
 319
 320         if (read_cmdline(pid, tid, process->name, sizeof(process->name)))
 321                 goto free;
 322
 323         if (maps != NULL) {
 324                 list_for_each_entry(maps, &process->maps->list, list) {
 325                         process->pages_present += maps->pages_present;
 326                         process->pages_swapped += maps->pages_swapped;
 327                 }
 328         }
 329
 330         list_add_tail(&process->list, &(*process_list)->list);
 331
 332         return 1;
 333 free:
 334         free(process);
 335
 336         return 0;
 337 }
 338
 339 static int parse_pid(DIR **dir)
 340 {
 341         struct dirent *dirent;
 342         int error;
 343
 344 restart:
 345         dirent = readdir(*dir);
 346         if (!dirent) {
 347                 if (errno == 0) {
 348                         closedir(*dir);
 349                         *dir = NULL;
 350                         return 0;
 351                 }
 352                 error = errno;
 353                 printf("Failed to read /proc directory: %s\n", strerror(error));
 354                 return -1;
 355         }
 356
 357         if (dirent->d_name[0] < '0' || dirent->d_name[0] > '9')
 358                 goto restart;
 359
 360         return atoi(dirent->d_name);
 361 }
 362
 363 static int opendir_check(DIR **dir, const char *path)
 364 {
 365         int error;
 366
 367         if (!*dir) {
 368                 *dir = opendir(path);
 369                 if (!dir) {
 370                         error = errno;
 371                         fprintf(stderr, "Failed to open %s directory: %s\n",
 372                                 path, strerror(error));
 373                         return -1;
 374                 }
 375         }
 376
 377         return 0;
 378 }
 379
 380 static int get_next_tid(int pid, DIR **dir)
 381 {
 382         if (*dir == NULL) {
 383                 char path[64];
 384
 385                 snprintf(path, sizeof(path), "/proc/%d/task/", pid);
 386                 if (opendir_check(dir, path))
 387                         return -1;
 388         }
 389
 390         return parse_pid(dir);
 391 }
 392
 393 static int get_next_pid(DIR **dir)
 394 {
 395         if (opendir_check(dir, "/proc"))
 396                 return -1;
 397
 398         return parse_pid(dir);
 399 }
 400
 401 static int get_next_pid_by_name(DIR **dir, char *name)
 402 {
 403         int pid;
 404         char *pname;
 405
 406         if (opendir_check(dir, "/proc"))
 407                 return -1;
 408
 409         while (1) {
 410                 pid = parse_pid(dir);
 411                 if (pid <= 0)
 412                         break;
 413
 414                 pname = get_name_by_pid(pid);
 415                 if (pname == NULL)
 416                         continue;
 417                 if (strcmp(pname, name))
 418                         continue;
 419
 420                 return pid;
 421         }
 422
 423         return 0;
 424 }
 425
 426 static int read_pageframe_with_threads(int pid,
 427                                 struct pageframe *pageframe,
 428                                 struct process **process_list,
 429                                 struct parse_opts *opts)
 430 {
 431         DIR *dir = NULL;
 432         int tid;
 433         int count = 0;
 434
 435         while (1) {
 436                 if (opts->with_threads)
 437                         tid = get_next_tid(pid, &dir);
 438                 else
 439                         tid = pid;
 440
 441                 if (tid <= 0)
 442                         return count;
 443
 444                 count += read_pageframe(pid, tid, pageframe, process_list,
 445                                         opts);
 446
 447                 if (!opts->with_threads)
 448                         break;
 449         }
 450
 451         return count;
 452 }
 453
 454 int scan_all_pids(struct pageframe *pf, struct process **process_list,
 455                 struct parse_opts *opts)
 456 {
 457         DIR *dir = NULL;
 458         int pid;
 459         int count = 0;
 460
 461         if (opts->parse_mask & PARSE_PROCESS_NAME) {
 462                 while ((pid = get_next_pid_by_name(&dir, opts->name))) {
 463                         count += read_pageframe_with_threads(pid, pf,
 464                                                         process_list,
 465                                                         opts);
 466                 }
 467                 dir = NULL;
 468         }
 469
 470         if (opts->parse_mask & PARSE_PID)
 471                 count = read_pageframe_with_threads(opts->pid, pf, process_list,
 472                                                 opts);
 473
 474         if ((count == 0) && !(opts->parse_mask & PARSE_MAP_NAME)) {
 475                 printf("Failed to find any matching processes "
 476                         "with given arguments\n");
 477                 return -1;
 478         }
 479
 480         if (opts->parse_mask & PARSE_DUMP)
 481                 return 0;
 482
 483         while (1) {
 484                 pid = get_next_pid(&dir);
 485                 if (pid <= 0)
 486                         break;
 487                 read_pageframe_with_threads(pid, pf, process_list, opts);
 488         }
 489
 490         return 0;
 491 }