tools/perf/util/evlist.c

   1 /*
   2  * Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
   3  *
   4  * Parts came from builtin-{top,stat,record}.c, see those files for further
   5  * copyright notes.
   6  *
   7  * Released under the GPL v2. (and only v2, not any later version)
   8  */
   9 #include <poll.h>
  10 #include "cpumap.h"
  11 #include "thread_map.h"
  12 #include "evlist.h"
  13 #include "evsel.h"
  14 #include "util.h"
  15 #include "debug.h"
  16
  17 #include <sys/mman.h>
  18
  19 #include <linux/bitops.h>
  20 #include <linux/hash.h>
  21
  22 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
  23 #define SID(e, x, y) xyarray__entry(e->sample_id, x, y)
  24
  25 void perf_evlist__init(struct perf_evlist *evlist, struct cpu_map *cpus,
  26                        struct thread_map *threads)
  27 {
  28         int i;
  29
  30         for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)
  31                 INIT_HLIST_HEAD(&evlist->heads[i]);
  32         INIT_LIST_HEAD(&evlist->entries);
  33         perf_evlist__set_maps(evlist, cpus, threads);
  34 }
  35
  36 struct perf_evlist *perf_evlist__new(struct cpu_map *cpus,
  37                                      struct thread_map *threads)
  38 {
  39         struct perf_evlist *evlist = zalloc(sizeof(*evlist));
  40
  41         if (evlist != NULL)
  42                 perf_evlist__init(evlist, cpus, threads);
  43
  44         return evlist;
  45 }
  46
  47 static void perf_evlist__purge(struct perf_evlist *evlist)
  48 {
  49         struct perf_evsel *pos, *n;
  50
  51         list_for_each_entry_safe(pos, n, &evlist->entries, node) {
  52                 list_del_init(&pos->node);
  53                 perf_evsel__delete(pos);
  54         }
  55
  56         evlist->nr_entries = 0;
  57 }
  58
  59 void perf_evlist__exit(struct perf_evlist *evlist)
  60 {
  61         free(evlist->mmap);
  62         free(evlist->pollfd);
  63         evlist->mmap = NULL;
  64         evlist->pollfd = NULL;
  65 }
  66
  67 void perf_evlist__delete(struct perf_evlist *evlist)
  68 {
  69         perf_evlist__purge(evlist);
  70         perf_evlist__exit(evlist);
  71         free(evlist);
  72 }
  73
  74 void perf_evlist__add(struct perf_evlist *evlist, struct perf_evsel *entry)
  75 {
  76         list_add_tail(&entry->node, &evlist->entries);
  77         ++evlist->nr_entries;
  78 }
  79
  80 int perf_evlist__add_default(struct perf_evlist *evlist)
  81 {
  82         struct perf_event_attr attr = {
  83                 .type = PERF_TYPE_HARDWARE,
  84                 .config = PERF_COUNT_HW_CPU_CYCLES,
  85         };
  86         struct perf_evsel *evsel = perf_evsel__new(&attr, 0);
  87
  88         if (evsel == NULL)
  89                 return -ENOMEM;
  90
  91         perf_evlist__add(evlist, evsel);
  92         return 0;
  93 }
  94
  95 int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
  96 {
  97         int nfds = evlist->cpus->nr * evlist->threads->nr * evlist->nr_entries;
  98         evlist->pollfd = malloc(sizeof(struct pollfd) * nfds);
  99         return evlist->pollfd != NULL ? 0 : -ENOMEM;
 100 }
 101
 102 void perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd)
 103 {
 104         fcntl(fd, F_SETFL, O_NONBLOCK);
 105         evlist->pollfd[evlist->nr_fds].fd = fd;
 106         evlist->pollfd[evlist->nr_fds].events = POLLIN;
 107         evlist->nr_fds++;
 108 }
 109
 110 static void perf_evlist__id_hash(struct perf_evlist *evlist,
 111                                  struct perf_evsel *evsel,
 112                                  int cpu, int thread, u64 id)
 113 {
 114         int hash;
 115         struct perf_sample_id *sid = SID(evsel, cpu, thread);
 116
 117         sid->id = id;
 118         sid->evsel = evsel;
 119         hash = hash_64(sid->id, PERF_EVLIST__HLIST_BITS);
 120         hlist_add_head(&sid->node, &evlist->heads[hash]);
 121 }
 122
 123 void perf_evlist__id_add(struct perf_evlist *evlist, struct perf_evsel *evsel,
 124                          int cpu, int thread, u64 id)
 125 {
 126         perf_evlist__id_hash(evlist, evsel, cpu, thread, id);
 127         evsel->id[evsel->ids++] = id;
 128 }
 129
 130 static int perf_evlist__id_add_fd(struct perf_evlist *evlist,
 131                                   struct perf_evsel *evsel,
 132                                   int cpu, int thread, int fd)
 133 {
 134         u64 read_data[4] = { 0, };
 135         int id_idx = 1; /* The first entry is the counter value */
 136
 137         if (!(evsel->attr.read_format & PERF_FORMAT_ID) ||
 138             read(fd, &read_data, sizeof(read_data)) == -1)
 139                 return -1;
 140
 141         if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
 142                 ++id_idx;
 143         if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
 144                 ++id_idx;
 145
 146         perf_evlist__id_add(evlist, evsel, cpu, thread, read_data[id_idx]);
 147         return 0;
 148 }
 149
 150 struct perf_evsel *perf_evlist__id2evsel(struct perf_evlist *evlist, u64 id)
 151 {
 152         struct hlist_head *head;
 153         struct hlist_node *pos;
 154         struct perf_sample_id *sid;
 155         int hash;
 156
 157         if (evlist->nr_entries == 1)
 158                 return list_entry(evlist->entries.next, struct perf_evsel, node);
 159
 160         hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
 161         head = &evlist->heads[hash];
 162
 163         hlist_for_each_entry(sid, pos, head, node)
 164                 if (sid->id == id)
 165                         return sid->evsel;
 166         return NULL;
 167 }
 168
 169 union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx)
 170 {
 171         /* XXX Move this to perf.c, making it generally available */
 172         unsigned int page_size = sysconf(_SC_PAGE_SIZE);
 173         struct perf_mmap *md = &evlist->mmap[idx];
 174         unsigned int head = perf_mmap__read_head(md);
 175         unsigned int old = md->prev;
 176         unsigned char *data = md->base + page_size;
 177         union perf_event *event = NULL;
 178
 179         if (evlist->overwrite) {
 180                 /*
 181                  * If we're further behind than half the buffer, there's a chance
 182                  * the writer will bite our tail and mess up the samples under us.
 183                  *
 184                  * If we somehow ended up ahead of the head, we got messed up.
 185                  *
 186                  * In either case, truncate and restart at head.
 187                  */
 188                 int diff = head - old;
 189                 if (diff > md->mask / 2 || diff < 0) {
 190                         fprintf(stderr, "WARNING: failed to keep up with mmap data.\n");
 191
 192                         /*
 193                          * head points to a known good entry, start there.
 194                          */
 195                         old = head;
 196                 }
 197         }
 198
 199         if (old != head) {
 200                 size_t size;
 201
 202                 event = (union perf_event *)&data[old & md->mask];
 203                 size = event->header.size;
 204
 205                 /*
 206                  * Event straddles the mmap boundary -- header should always
 207                  * be inside due to u64 alignment of output.
 208                  */
 209                 if ((old & md->mask) + size != ((old + size) & md->mask)) {
 210                         unsigned int offset = old;
 211                         unsigned int len = min(sizeof(*event), size), cpy;
 212                         void *dst = &evlist->event_copy;
 213
 214                         do {
 215                                 cpy = min(md->mask + 1 - (offset & md->mask), len);
 216                                 memcpy(dst, &data[offset & md->mask], cpy);
 217                                 offset += cpy;
 218                                 dst += cpy;
 219                                 len -= cpy;
 220                         } while (len);
 221
 222                         event = &evlist->event_copy;
 223                 }
 224
 225                 old += size;
 226         }
 227
 228         md->prev = old;
 229
 230         if (!evlist->overwrite)
 231                 perf_mmap__write_tail(md, old);
 232
 233         return event;
 234 }
 235
 236 void perf_evlist__munmap(struct perf_evlist *evlist)
 237 {
 238         int i;
 239
 240         for (i = 0; i < evlist->nr_mmaps; i++) {
 241                 if (evlist->mmap[i].base != NULL) {
 242                         munmap(evlist->mmap[i].base, evlist->mmap_len);
 243                         evlist->mmap[i].base = NULL;
 244                 }
 245         }
 246
 247         free(evlist->mmap);
 248         evlist->mmap = NULL;
 249 }
 250
 251 int perf_evlist__alloc_mmap(struct perf_evlist *evlist)
 252 {
 253         evlist->nr_mmaps = evlist->cpus->nr;
 254         if (evlist->cpus->map[0] == -1)
 255                 evlist->nr_mmaps = evlist->threads->nr;
 256         evlist->mmap = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap));
 257         return evlist->mmap != NULL ? 0 : -ENOMEM;
 258 }
 259
 260 static int __perf_evlist__mmap(struct perf_evlist *evlist, struct perf_evsel *evsel,
 261                                int idx, int prot, int mask, int fd)
 262 {
 263         evlist->mmap[idx].prev = 0;
 264         evlist->mmap[idx].mask = mask;
 265         evlist->mmap[idx].base = mmap(NULL, evlist->mmap_len, prot,
 266                                       MAP_SHARED, fd, 0);
 267         if (evlist->mmap[idx].base == MAP_FAILED) {
 268                 if (evlist->cpus->map[idx] == -1 && evsel->attr.inherit)
 269                         ui__warning("Inherit is not allowed on per-task "
 270                                     "events using mmap.\n");
 271                 return -1;
 272         }
 273
 274         perf_evlist__add_pollfd(evlist, fd);
 275         return 0;
 276 }
 277
 278 static int perf_evlist__mmap_per_cpu(struct perf_evlist *evlist, int prot, int mask)
 279 {
 280         struct perf_evsel *evsel;
 281         int cpu, thread;
 282
 283         for (cpu = 0; cpu < evlist->cpus->nr; cpu++) {
 284                 int output = -1;
 285
 286                 for (thread = 0; thread < evlist->threads->nr; thread++) {
 287                         list_for_each_entry(evsel, &evlist->entries, node) {
 288                                 int fd = FD(evsel, cpu, thread);
 289
 290                                 if (output == -1) {
 291                                         output = fd;
 292                                         if (__perf_evlist__mmap(evlist, evsel, cpu,
 293                                                                 prot, mask, output) < 0)
 294                                                 goto out_unmap;
 295                                 } else {
 296                                         if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, output) != 0)
 297                                                 goto out_unmap;
 298                                 }
 299
 300                                 if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
 301                                     perf_evlist__id_add_fd(evlist, evsel, cpu, thread, fd) < 0)
 302                                         goto out_unmap;
 303                         }
 304                 }
 305         }
 306
 307         return 0;
 308
 309 out_unmap:
 310         for (cpu = 0; cpu < evlist->cpus->nr; cpu++) {
 311                 if (evlist->mmap[cpu].base != NULL) {
 312                         munmap(evlist->mmap[cpu].base, evlist->mmap_len);
 313                         evlist->mmap[cpu].base = NULL;
 314                 }
 315         }
 316         return -1;
 317 }
 318
 319 static int perf_evlist__mmap_per_thread(struct perf_evlist *evlist, int prot, int mask)
 320 {
 321         struct perf_evsel *evsel;
 322         int thread;
 323
 324         for (thread = 0; thread < evlist->threads->nr; thread++) {
 325                 int output = -1;
 326
 327                 list_for_each_entry(evsel, &evlist->entries, node) {
 328                         int fd = FD(evsel, 0, thread);
 329
 330                         if (output == -1) {
 331                                 output = fd;
 332                                 if (__perf_evlist__mmap(evlist, evsel, thread,
 333                                                         prot, mask, output) < 0)
 334                                         goto out_unmap;
 335                         } else {
 336                                 if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, output) != 0)
 337                                         goto out_unmap;
 338                         }
 339
 340                         if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
 341                             perf_evlist__id_add_fd(evlist, evsel, 0, thread, fd) < 0)
 342                                 goto out_unmap;
 343                 }
 344         }
 345
 346         return 0;
 347
 348 out_unmap:
 349         for (thread = 0; thread < evlist->threads->nr; thread++) {
 350                 if (evlist->mmap[thread].base != NULL) {
 351                         munmap(evlist->mmap[thread].base, evlist->mmap_len);
 352                         evlist->mmap[thread].base = NULL;
 353                 }
 354         }
 355         return -1;
 356 }
 357
 358 /** perf_evlist__mmap - Create per cpu maps to receive events
 359  *
 360  * @evlist - list of events
 361  * @pages - map length in pages
 362  * @overwrite - overwrite older events?
 363  *
 364  * If overwrite is false the user needs to signal event consuption using:
 365  *
 366  *      struct perf_mmap *m = &evlist->mmap[cpu];
 367  *      unsigned int head = perf_mmap__read_head(m);
 368  *
 369  *      perf_mmap__write_tail(m, head)
 370  *
 371  * Using perf_evlist__read_on_cpu does this automatically.
 372  */
 373 int perf_evlist__mmap(struct perf_evlist *evlist, int pages, bool overwrite)
 374 {
 375         unsigned int page_size = sysconf(_SC_PAGE_SIZE);
 376         int mask = pages * page_size - 1;
 377         struct perf_evsel *evsel;
 378         const struct cpu_map *cpus = evlist->cpus;
 379         const struct thread_map *threads = evlist->threads;
 380         int prot = PROT_READ | (overwrite ? 0 : PROT_WRITE);
 381
 382         if (evlist->mmap == NULL && perf_evlist__alloc_mmap(evlist) < 0)
 383                 return -ENOMEM;
 384
 385         if (evlist->pollfd == NULL && perf_evlist__alloc_pollfd(evlist) < 0)
 386                 return -ENOMEM;
 387
 388         evlist->overwrite = overwrite;
 389         evlist->mmap_len = (pages + 1) * page_size;
 390
 391         list_for_each_entry(evsel, &evlist->entries, node) {
 392                 if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
 393                     evsel->sample_id == NULL &&
 394                     perf_evsel__alloc_id(evsel, cpus->nr, threads->nr) < 0)
 395                         return -ENOMEM;
 396         }
 397
 398         if (evlist->cpus->map[0] == -1)
 399                 return perf_evlist__mmap_per_thread(evlist, prot, mask);
 400
 401         return perf_evlist__mmap_per_cpu(evlist, prot, mask);
 402 }
 403
 404 int perf_evlist__create_maps(struct perf_evlist *evlist, pid_t target_pid,
 405                              pid_t target_tid, const char *cpu_list)
 406 {
 407         evlist->threads = thread_map__new(target_pid, target_tid);
 408
 409         if (evlist->threads == NULL)
 410                 return -1;
 411
 412         if (cpu_list == NULL && target_tid != -1)
 413                 evlist->cpus = cpu_map__dummy_new();
 414         else
 415                 evlist->cpus = cpu_map__new(cpu_list);
 416
 417         if (evlist->cpus == NULL)
 418                 goto out_delete_threads;
 419
 420         return 0;
 421
 422 out_delete_threads:
 423         thread_map__delete(evlist->threads);
 424         return -1;
 425 }
 426
 427 void perf_evlist__delete_maps(struct perf_evlist *evlist)
 428 {
 429         cpu_map__delete(evlist->cpus);
 430         thread_map__delete(evlist->threads);
 431         evlist->cpus    = NULL;
 432         evlist->threads = NULL;
 433 }
 434
 435 int perf_evlist__set_filters(struct perf_evlist *evlist)
 436 {
 437         const struct thread_map *threads = evlist->threads;
 438         const struct cpu_map *cpus = evlist->cpus;
 439         struct perf_evsel *evsel;
 440         char *filter;
 441         int thread;
 442         int cpu;
 443         int err;
 444         int fd;
 445
 446         list_for_each_entry(evsel, &evlist->entries, node) {
 447                 filter = evsel->filter;
 448                 if (!filter)
 449                         continue;
 450                 for (cpu = 0; cpu < cpus->nr; cpu++) {
 451                         for (thread = 0; thread < threads->nr; thread++) {
 452                                 fd = FD(evsel, cpu, thread);
 453                                 err = ioctl(fd, PERF_EVENT_IOC_SET_FILTER, filter);
 454                                 if (err)
 455                                         return err;
 456                         }
 457                 }
 458         }
 459
 460         return 0;
 461 }