tools/perf/util/thread_map.c

   1 #include <dirent.h>
   2 #include <limits.h>
   3 #include <stdbool.h>
   4 #include <stdlib.h>
   5 #include <stdio.h>
   6 #include <sys/types.h>
   7 #include <sys/stat.h>
   8 #include <unistd.h>
   9 #include "strlist.h"
  10 #include <string.h>
  11 #include "thread_map.h"
  12 #include "util.h"
  13
  14 /* Skip "." and ".." directories */
  15 static int filter(const struct dirent *dir)
  16 {
  17         if (dir->d_name[0] == '.')
  18                 return 0;
  19         else
  20                 return 1;
  21 }
  22
  23 static struct thread_map *thread_map__realloc(struct thread_map *map, int nr)
  24 {
  25         size_t size = sizeof(*map) + sizeof(pid_t) * nr;
  26
  27         return realloc(map, size);
  28 }
  29
  30 #define thread_map__alloc(__nr) thread_map__realloc(NULL, __nr)
  31
  32 struct thread_map *thread_map__new_by_pid(pid_t pid)
  33 {
  34         struct thread_map *threads;
  35         char name[256];
  36         int items;
  37         struct dirent **namelist = NULL;
  38         int i;
  39
  40         sprintf(name, "/proc/%d/task", pid);
  41         items = scandir(name, &namelist, filter, NULL);
  42         if (items <= 0)
  43                 return NULL;
  44
  45         threads = thread_map__alloc(items);
  46         if (threads != NULL) {
  47                 for (i = 0; i < items; i++)
  48                         threads->map[i] = atoi(namelist[i]->d_name);
  49                 threads->nr = items;
  50         }
  51
  52         for (i=0; i<items; i++)
  53                 zfree(&namelist[i]);
  54         free(namelist);
  55
  56         return threads;
  57 }
  58
  59 struct thread_map *thread_map__new_by_tid(pid_t tid)
  60 {
  61         struct thread_map *threads = thread_map__alloc(1);
  62
  63         if (threads != NULL) {
  64                 threads->map[0] = tid;
  65                 threads->nr     = 1;
  66         }
  67
  68         return threads;
  69 }
  70
  71 struct thread_map *thread_map__new_by_uid(uid_t uid)
  72 {
  73         DIR *proc;
  74         int max_threads = 32, items, i;
  75         char path[256];
  76         struct dirent dirent, *next, **namelist = NULL;
  77         struct thread_map *threads = thread_map__alloc(max_threads);
  78
  79         if (threads == NULL)
  80                 goto out;
  81
  82         proc = opendir("/proc");
  83         if (proc == NULL)
  84                 goto out_free_threads;
  85
  86         threads->nr = 0;
  87
  88         while (!readdir_r(proc, &dirent, &next) && next) {
  89                 char *end;
  90                 bool grow = false;
  91                 struct stat st;
  92                 pid_t pid = strtol(dirent.d_name, &end, 10);
  93
  94                 if (*end) /* only interested in proper numerical dirents */
  95                         continue;
  96
  97                 snprintf(path, sizeof(path), "/proc/%s", dirent.d_name);
  98
  99                 if (stat(path, &st) != 0)
 100                         continue;
 101
 102                 if (st.st_uid != uid)
 103                         continue;
 104
 105                 snprintf(path, sizeof(path), "/proc/%d/task", pid);
 106                 items = scandir(path, &namelist, filter, NULL);
 107                 if (items <= 0)
 108                         goto out_free_closedir;
 109
 110                 while (threads->nr + items >= max_threads) {
 111                         max_threads *= 2;
 112                         grow = true;
 113                 }
 114
 115                 if (grow) {
 116                         struct thread_map *tmp;
 117
 118                         tmp = realloc(threads, (sizeof(*threads) +
 119                                                 max_threads * sizeof(pid_t)));
 120                         if (tmp == NULL)
 121                                 goto out_free_namelist;
 122
 123                         threads = tmp;
 124                 }
 125
 126                 for (i = 0; i < items; i++)
 127                         threads->map[threads->nr + i] = atoi(namelist[i]->d_name);
 128
 129                 for (i = 0; i < items; i++)
 130                         zfree(&namelist[i]);
 131                 free(namelist);
 132
 133                 threads->nr += items;
 134         }
 135
 136 out_closedir:
 137         closedir(proc);
 138 out:
 139         return threads;
 140
 141 out_free_threads:
 142         free(threads);
 143         return NULL;
 144
 145 out_free_namelist:
 146         for (i = 0; i < items; i++)
 147                 zfree(&namelist[i]);
 148         free(namelist);
 149
 150 out_free_closedir:
 151         zfree(&threads);
 152         goto out_closedir;
 153 }
 154
 155 struct thread_map *thread_map__new(pid_t pid, pid_t tid, uid_t uid)
 156 {
 157         if (pid != -1)
 158                 return thread_map__new_by_pid(pid);
 159
 160         if (tid == -1 && uid != UINT_MAX)
 161                 return thread_map__new_by_uid(uid);
 162
 163         return thread_map__new_by_tid(tid);
 164 }
 165
 166 static struct thread_map *thread_map__new_by_pid_str(const char *pid_str)
 167 {
 168         struct thread_map *threads = NULL, *nt;
 169         char name[256];
 170         int items, total_tasks = 0;
 171         struct dirent **namelist = NULL;
 172         int i, j = 0;
 173         pid_t pid, prev_pid = INT_MAX;
 174         char *end_ptr;
 175         struct str_node *pos;
 176         struct strlist *slist = strlist__new(false, pid_str);
 177
 178         if (!slist)
 179                 return NULL;
 180
 181         strlist__for_each(pos, slist) {
 182                 pid = strtol(pos->s, &end_ptr, 10);
 183
 184                 if (pid == INT_MIN || pid == INT_MAX ||
 185                     (*end_ptr != '\0' && *end_ptr != ','))
 186                         goto out_free_threads;
 187
 188                 if (pid == prev_pid)
 189                         continue;
 190
 191                 sprintf(name, "/proc/%d/task", pid);
 192                 items = scandir(name, &namelist, filter, NULL);
 193                 if (items <= 0)
 194                         goto out_free_threads;
 195
 196                 total_tasks += items;
 197                 nt = thread_map__realloc(threads, total_tasks);
 198                 if (nt == NULL)
 199                         goto out_free_namelist;
 200
 201                 threads = nt;
 202
 203                 for (i = 0; i < items; i++) {
 204                         threads->map[j++] = atoi(namelist[i]->d_name);
 205                         zfree(&namelist[i]);
 206                 }
 207                 threads->nr = total_tasks;
 208                 free(namelist);
 209         }
 210
 211 out:
 212         strlist__delete(slist);
 213         return threads;
 214
 215 out_free_namelist:
 216         for (i = 0; i < items; i++)
 217                 zfree(&namelist[i]);
 218         free(namelist);
 219
 220 out_free_threads:
 221         zfree(&threads);
 222         goto out;
 223 }
 224
 225 struct thread_map *thread_map__new_dummy(void)
 226 {
 227         struct thread_map *threads = thread_map__alloc(1);
 228
 229         if (threads != NULL) {
 230                 threads->map[0] = -1;
 231                 threads->nr     = 1;
 232         }
 233         return threads;
 234 }
 235
 236 static struct thread_map *thread_map__new_by_tid_str(const char *tid_str)
 237 {
 238         struct thread_map *threads = NULL, *nt;
 239         int ntasks = 0;
 240         pid_t tid, prev_tid = INT_MAX;
 241         char *end_ptr;
 242         struct str_node *pos;
 243         struct strlist *slist;
 244
 245         /* perf-stat expects threads to be generated even if tid not given */
 246         if (!tid_str)
 247                 return thread_map__new_dummy();
 248
 249         slist = strlist__new(false, tid_str);
 250         if (!slist)
 251                 return NULL;
 252
 253         strlist__for_each(pos, slist) {
 254                 tid = strtol(pos->s, &end_ptr, 10);
 255
 256                 if (tid == INT_MIN || tid == INT_MAX ||
 257                     (*end_ptr != '\0' && *end_ptr != ','))
 258                         goto out_free_threads;
 259
 260                 if (tid == prev_tid)
 261                         continue;
 262
 263                 ntasks++;
 264                 nt = thread_map__realloc(threads, ntasks);
 265
 266                 if (nt == NULL)
 267                         goto out_free_threads;
 268
 269                 threads = nt;
 270                 threads->map[ntasks - 1] = tid;
 271                 threads->nr              = ntasks;
 272         }
 273 out:
 274         return threads;
 275
 276 out_free_threads:
 277         zfree(&threads);
 278         goto out;
 279 }
 280
 281 struct thread_map *thread_map__new_str(const char *pid, const char *tid,
 282                                        uid_t uid)
 283 {
 284         if (pid)
 285                 return thread_map__new_by_pid_str(pid);
 286
 287         if (!tid && uid != UINT_MAX)
 288                 return thread_map__new_by_uid(uid);
 289
 290         return thread_map__new_by_tid_str(tid);
 291 }
 292
 293 void thread_map__delete(struct thread_map *threads)
 294 {
 295         free(threads);
 296 }
 297
 298 size_t thread_map__fprintf(struct thread_map *threads, FILE *fp)
 299 {
 300         int i;
 301         size_t printed = fprintf(fp, "%d thread%s: ",
 302                                  threads->nr, threads->nr > 1 ? "s" : "");
 303         for (i = 0; i < threads->nr; ++i)
 304                 printed += fprintf(fp, "%s%d", i ? ", " : "", threads->map[i]);
 305
 306         return printed + fprintf(fp, "\n");
 307 }