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