tools/perf/util/event.c

   1 #include <linux/types.h>
   2 #include "event.h"
   3 #include "debug.h"
   4 #include "string.h"
   5 #include "thread.h"
   6
   7 static pid_t event__synthesize_comm(pid_t pid, int full,
   8                                     int (*process)(event_t *event))
   9 {
  10         event_t ev;
  11         char filename[PATH_MAX];
  12         char bf[BUFSIZ];
  13         FILE *fp;
  14         size_t size = 0;
  15         DIR *tasks;
  16         struct dirent dirent, *next;
  17         pid_t tgid = 0;
  18
  19         snprintf(filename, sizeof(filename), "/proc/%d/status", pid);
  20
  21         fp = fopen(filename, "r");
  22         if (fp == NULL) {
  23 out_race:
  24                 /*
  25                  * We raced with a task exiting - just return:
  26                  */
  27                 pr_debug("couldn't open %s\n", filename);
  28                 return 0;
  29         }
  30
  31         memset(&ev.comm, 0, sizeof(ev.comm));
  32         while (!ev.comm.comm[0] || !ev.comm.pid) {
  33                 if (fgets(bf, sizeof(bf), fp) == NULL)
  34                         goto out_failure;
  35
  36                 if (memcmp(bf, "Name:", 5) == 0) {
  37                         char *name = bf + 5;
  38                         while (*name && isspace(*name))
  39                                 ++name;
  40                         size = strlen(name) - 1;
  41                         memcpy(ev.comm.comm, name, size++);
  42                 } else if (memcmp(bf, "Tgid:", 5) == 0) {
  43                         char *tgids = bf + 5;
  44                         while (*tgids && isspace(*tgids))
  45                                 ++tgids;
  46                         tgid = ev.comm.pid = atoi(tgids);
  47                 }
  48         }
  49
  50         ev.comm.header.type = PERF_RECORD_COMM;
  51         size = ALIGN(size, sizeof(u64));
  52         ev.comm.header.size = sizeof(ev.comm) - (sizeof(ev.comm.comm) - size);
  53
  54         if (!full) {
  55                 ev.comm.tid = pid;
  56
  57                 process(&ev);
  58                 goto out_fclose;
  59         }
  60
  61         snprintf(filename, sizeof(filename), "/proc/%d/task", pid);
  62
  63         tasks = opendir(filename);
  64         if (tasks == NULL)
  65                 goto out_race;
  66
  67         while (!readdir_r(tasks, &dirent, &next) && next) {
  68                 char *end;
  69                 pid = strtol(dirent.d_name, &end, 10);
  70                 if (*end)
  71                         continue;
  72
  73                 ev.comm.tid = pid;
  74
  75                 process(&ev);
  76         }
  77         closedir(tasks);
  78
  79 out_fclose:
  80         fclose(fp);
  81         return tgid;
  82
  83 out_failure:
  84         pr_warning("couldn't get COMM and pgid, malformed %s\n", filename);
  85         return -1;
  86 }
  87
  88 static int event__synthesize_mmap_events(pid_t pid, pid_t tgid,
  89                                          int (*process)(event_t *event))
  90 {
  91         char filename[PATH_MAX];
  92         FILE *fp;
  93
  94         snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);
  95
  96         fp = fopen(filename, "r");
  97         if (fp == NULL) {
  98                 /*
  99                  * We raced with a task exiting - just return:
 100                  */
 101                 pr_debug("couldn't open %s\n", filename);
 102                 return -1;
 103         }
 104
 105         while (1) {
 106                 char bf[BUFSIZ], *pbf = bf;
 107                 event_t ev = {
 108                         .header = { .type = PERF_RECORD_MMAP },
 109                 };
 110                 int n;
 111                 size_t size;
 112                 if (fgets(bf, sizeof(bf), fp) == NULL)
 113                         break;
 114
 115                 /* 00400000-0040c000 r-xp 00000000 fd:01 41038  /bin/cat */
 116                 n = hex2u64(pbf, &ev.mmap.start);
 117                 if (n < 0)
 118                         continue;
 119                 pbf += n + 1;
 120                 n = hex2u64(pbf, &ev.mmap.len);
 121                 if (n < 0)
 122                         continue;
 123                 pbf += n + 3;
 124                 if (*pbf == 'x') { /* vm_exec */
 125                         char *execname = strchr(bf, '/');
 126
 127                         /* Catch VDSO */
 128                         if (execname == NULL)
 129                                 execname = strstr(bf, "[vdso]");
 130
 131                         if (execname == NULL)
 132                                 continue;
 133
 134                         size = strlen(execname);
 135                         execname[size - 1] = '\0'; /* Remove \n */
 136                         memcpy(ev.mmap.filename, execname, size);
 137                         size = ALIGN(size, sizeof(u64));
 138                         ev.mmap.len -= ev.mmap.start;
 139                         ev.mmap.header.size = (sizeof(ev.mmap) -
 140                                                (sizeof(ev.mmap.filename) - size));
 141                         ev.mmap.pid = tgid;
 142                         ev.mmap.tid = pid;
 143
 144                         process(&ev);
 145                 }
 146         }
 147
 148         fclose(fp);
 149         return 0;
 150 }
 151
 152 int event__synthesize_thread(pid_t pid, int (*process)(event_t *event))
 153 {
 154         pid_t tgid = event__synthesize_comm(pid, 1, process);
 155         if (tgid == -1)
 156                 return -1;
 157         return event__synthesize_mmap_events(pid, tgid, process);
 158 }
 159
 160 void event__synthesize_threads(int (*process)(event_t *event))
 161 {
 162         DIR *proc;
 163         struct dirent dirent, *next;
 164
 165         proc = opendir("/proc");
 166
 167         while (!readdir_r(proc, &dirent, &next) && next) {
 168                 char *end;
 169                 pid_t pid = strtol(dirent.d_name, &end, 10);
 170
 171                 if (*end) /* only interested in proper numerical dirents */
 172                         continue;
 173
 174                 event__synthesize_thread(pid, process);
 175         }
 176
 177         closedir(proc);
 178 }
 179
 180 char *event__cwd;
 181 int  event__cwdlen;
 182
 183 struct events_stats event__stats;
 184
 185 int event__process_comm(event_t *self)
 186 {
 187         struct thread *thread = threads__findnew(self->comm.pid);
 188
 189         dump_printf(": %s:%d\n", self->comm.comm, self->comm.pid);
 190
 191         if (thread == NULL || thread__set_comm(thread, self->comm.comm)) {
 192                 dump_printf("problem processing PERF_RECORD_COMM, skipping event.\n");
 193                 return -1;
 194         }
 195
 196         return 0;
 197 }
 198
 199 int event__process_lost(event_t *self)
 200 {
 201         dump_printf(": id:%Ld: lost:%Ld\n", self->lost.id, self->lost.lost);
 202         event__stats.lost += self->lost.lost;
 203         return 0;
 204 }
 205
 206 int event__process_mmap(event_t *self)
 207 {
 208         struct thread *thread = threads__findnew(self->mmap.pid);
 209         struct map *map = map__new(&self->mmap, MAP__FUNCTION,
 210                                    event__cwd, event__cwdlen);
 211
 212         dump_printf(" %d/%d: [%p(%p) @ %p]: %s\n",
 213                     self->mmap.pid, self->mmap.tid,
 214                     (void *)(long)self->mmap.start,
 215                     (void *)(long)self->mmap.len,
 216                     (void *)(long)self->mmap.pgoff,
 217                     self->mmap.filename);
 218
 219         if (thread == NULL || map == NULL)
 220                 dump_printf("problem processing PERF_RECORD_MMAP, skipping event.\n");
 221         else
 222                 thread__insert_map(thread, map);
 223
 224         return 0;
 225 }
 226
 227 int event__process_task(event_t *self)
 228 {
 229         struct thread *thread = threads__findnew(self->fork.pid);
 230         struct thread *parent = threads__findnew(self->fork.ppid);
 231
 232         dump_printf("(%d:%d):(%d:%d)\n", self->fork.pid, self->fork.tid,
 233                     self->fork.ppid, self->fork.ptid);
 234         /*
 235          * A thread clone will have the same PID for both parent and child.
 236          */
 237         if (thread == parent)
 238                 return 0;
 239
 240         if (self->header.type == PERF_RECORD_EXIT)
 241                 return 0;
 242
 243         if (thread == NULL || parent == NULL ||
 244             thread__fork(thread, parent) < 0) {
 245                 dump_printf("problem processing PERF_RECORD_FORK, skipping event.\n");
 246                 return -1;
 247         }
 248
 249         return 0;
 250 }
 251
 252 void thread__find_addr_location(struct thread *self, u8 cpumode,
 253                                 enum map_type type, u64 addr,
 254                                 struct addr_location *al,
 255                                 symbol_filter_t filter)
 256 {
 257         struct thread *thread = al->thread = self;
 258
 259         al->addr = addr;
 260
 261         if (cpumode & PERF_RECORD_MISC_KERNEL) {
 262                 al->level = 'k';
 263                 thread = kthread;
 264         } else if (cpumode & PERF_RECORD_MISC_USER)
 265                 al->level = '.';
 266         else {
 267                 al->level = 'H';
 268                 al->map = NULL;
 269                 al->sym = NULL;
 270                 return;
 271         }
 272 try_again:
 273         al->map = thread__find_map(thread, type, al->addr);
 274         if (al->map == NULL) {
 275                 /*
 276                  * If this is outside of all known maps, and is a negative
 277                  * address, try to look it up in the kernel dso, as it might be
 278                  * a vsyscall or vdso (which executes in user-mode).
 279                  *
 280                  * XXX This is nasty, we should have a symbol list in the
 281                  * "[vdso]" dso, but for now lets use the old trick of looking
 282                  * in the whole kernel symbol list.
 283                  */
 284                 if ((long long)al->addr < 0 && thread != kthread) {
 285                         thread = kthread;
 286                         goto try_again;
 287                 }
 288                 al->sym = NULL;
 289         } else {
 290                 al->addr = al->map->map_ip(al->map, al->addr);
 291                 al->sym = map__find_symbol(al->map, al->addr, filter);
 292         }
 293 }
 294
 295 int event__preprocess_sample(const event_t *self, struct addr_location *al,
 296                              symbol_filter_t filter)
 297 {
 298         u8 cpumode = self->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
 299         struct thread *thread = threads__findnew(self->ip.pid);
 300
 301         if (thread == NULL)
 302                 return -1;
 303
 304         dump_printf(" ... thread: %s:%d\n", thread->comm, thread->pid);
 305
 306         thread__find_addr_location(thread, cpumode, MAP__FUNCTION,
 307                                    self->ip.ip, al, filter);
 308         dump_printf(" ...... dso: %s\n",
 309                     al->map ? al->map->dso->long_name :
 310                         al->level == 'H' ? "[hypervisor]" : "<not found>");
 311         return 0;
 312 }