tools/perf/util/data_map.c

   1 #include "data_map.h"
   2 #include "symbol.h"
   3 #include "util.h"
   4 #include "debug.h"
   5
   6
   7 static struct perf_file_handler *curr_handler;
   8 static unsigned long    mmap_window = 32;
   9 static char             __cwd[PATH_MAX];
  10
  11 static int
  12 process_event_stub(event_t *event __used,
  13                    unsigned long offset __used,
  14                    unsigned long head __used)
  15 {
  16         return 0;
  17 }
  18
  19 void register_perf_file_handler(struct perf_file_handler *handler)
  20 {
  21         if (!handler->process_sample_event)
  22                 handler->process_sample_event = process_event_stub;
  23         if (!handler->process_mmap_event)
  24                 handler->process_mmap_event = process_event_stub;
  25         if (!handler->process_comm_event)
  26                 handler->process_comm_event = process_event_stub;
  27         if (!handler->process_fork_event)
  28                 handler->process_fork_event = process_event_stub;
  29         if (!handler->process_exit_event)
  30                 handler->process_exit_event = process_event_stub;
  31         if (!handler->process_lost_event)
  32                 handler->process_lost_event = process_event_stub;
  33         if (!handler->process_read_event)
  34                 handler->process_read_event = process_event_stub;
  35         if (!handler->process_throttle_event)
  36                 handler->process_throttle_event = process_event_stub;
  37         if (!handler->process_unthrottle_event)
  38                 handler->process_unthrottle_event = process_event_stub;
  39
  40         curr_handler = handler;
  41 }
  42
  43 static int
  44 process_event(event_t *event, unsigned long offset, unsigned long head)
  45 {
  46         trace_event(event);
  47
  48         switch (event->header.type) {
  49         case PERF_RECORD_SAMPLE:
  50                 return curr_handler->process_sample_event(event, offset, head);
  51         case PERF_RECORD_MMAP:
  52                 return curr_handler->process_mmap_event(event, offset, head);
  53         case PERF_RECORD_COMM:
  54                 return curr_handler->process_comm_event(event, offset, head);
  55         case PERF_RECORD_FORK:
  56                 return curr_handler->process_fork_event(event, offset, head);
  57         case PERF_RECORD_EXIT:
  58                 return curr_handler->process_exit_event(event, offset, head);
  59         case PERF_RECORD_LOST:
  60                 return curr_handler->process_lost_event(event, offset, head);
  61         case PERF_RECORD_READ:
  62                 return curr_handler->process_read_event(event, offset, head);
  63         case PERF_RECORD_THROTTLE:
  64                 return curr_handler->process_throttle_event(event, offset, head);
  65         case PERF_RECORD_UNTHROTTLE:
  66                 return curr_handler->process_unthrottle_event(event, offset, head);
  67         default:
  68                 curr_handler->total_unknown++;
  69                 return -1;
  70         }
  71 }
  72
  73 static int perf_header__read_build_ids(const struct perf_header *self,
  74                                        int input, off_t file_size)
  75 {
  76         off_t offset = self->data_offset + self->data_size;
  77         struct build_id_event bev;
  78         char filename[PATH_MAX];
  79         int err = -1;
  80
  81         if (lseek(input, offset, SEEK_SET) < 0)
  82                 return -1;
  83
  84         while (offset < file_size) {
  85                 struct dso *dso;
  86                 ssize_t len;
  87
  88                 if (read(input, &bev, sizeof(bev)) != sizeof(bev))
  89                         goto out;
  90
  91                 len = bev.header.size - sizeof(bev);
  92                 if (read(input, filename, len) != len)
  93                         goto out;
  94
  95                 dso = dsos__findnew(filename);
  96                 if (dso != NULL)
  97                         dso__set_build_id(dso, &bev.build_id);
  98
  99                 offset += bev.header.size;
 100         }
 101         err = 0;
 102 out:
 103         return err;
 104 }
 105
 106 int mmap_dispatch_perf_file(struct perf_header **pheader,
 107                             const char *input_name,
 108                             int force,
 109                             int full_paths,
 110                             int *cwdlen,
 111                             char **cwd)
 112 {
 113         int ret, rc = EXIT_FAILURE;
 114         struct perf_header *header;
 115         unsigned long head, shift;
 116         unsigned long offset = 0;
 117         struct stat input_stat;
 118         size_t  page_size;
 119         u64 sample_type;
 120         event_t *event;
 121         uint32_t size;
 122         int input;
 123         char *buf;
 124
 125         if (!curr_handler)
 126                 die("Forgot to register perf file handler");
 127
 128         page_size = getpagesize();
 129
 130         input = open(input_name, O_RDONLY);
 131         if (input < 0) {
 132                 fprintf(stderr, " failed to open file: %s", input_name);
 133                 if (!strcmp(input_name, "perf.data"))
 134                         fprintf(stderr, "  (try 'perf record' first)");
 135                 fprintf(stderr, "\n");
 136                 exit(-1);
 137         }
 138
 139         ret = fstat(input, &input_stat);
 140         if (ret < 0) {
 141                 perror("failed to stat file");
 142                 exit(-1);
 143         }
 144
 145         if (!force && input_stat.st_uid && (input_stat.st_uid != geteuid())) {
 146                 fprintf(stderr, "file: %s not owned by current user or root\n",
 147                         input_name);
 148                 exit(-1);
 149         }
 150
 151         if (!input_stat.st_size) {
 152                 fprintf(stderr, "zero-sized file, nothing to do!\n");
 153                 exit(0);
 154         }
 155
 156         *pheader = perf_header__read(input);
 157         header = *pheader;
 158         head = header->data_offset;
 159
 160         sample_type = perf_header__sample_type(header);
 161
 162         if (curr_handler->sample_type_check)
 163                 if (curr_handler->sample_type_check(sample_type) < 0)
 164                         exit(-1);
 165
 166         if (perf_header__has_feat(header, HEADER_BUILD_ID) &&
 167             perf_header__read_build_ids(header, input, input_stat.st_size))
 168                 pr_debug("failed to read buildids, continuing...\n");
 169
 170         if (load_kernel(NULL) < 0) {
 171                 perror("failed to load kernel symbols");
 172                 return EXIT_FAILURE;
 173         }
 174
 175         if (!full_paths) {
 176                 if (getcwd(__cwd, sizeof(__cwd)) == NULL) {
 177                         perror("failed to get the current directory");
 178                         return EXIT_FAILURE;
 179                 }
 180                 *cwd = __cwd;
 181                 *cwdlen = strlen(*cwd);
 182         } else {
 183                 *cwd = NULL;
 184                 *cwdlen = 0;
 185         }
 186
 187         shift = page_size * (head / page_size);
 188         offset += shift;
 189         head -= shift;
 190
 191 remap:
 192         buf = (char *)mmap(NULL, page_size * mmap_window, PROT_READ,
 193                            MAP_SHARED, input, offset);
 194         if (buf == MAP_FAILED) {
 195                 perror("failed to mmap file");
 196                 exit(-1);
 197         }
 198
 199 more:
 200         event = (event_t *)(buf + head);
 201
 202         size = event->header.size;
 203         if (!size)
 204                 size = 8;
 205
 206         if (head + event->header.size >= page_size * mmap_window) {
 207                 int munmap_ret;
 208
 209                 shift = page_size * (head / page_size);
 210
 211                 munmap_ret = munmap(buf, page_size * mmap_window);
 212                 assert(munmap_ret == 0);
 213
 214                 offset += shift;
 215                 head -= shift;
 216                 goto remap;
 217         }
 218
 219         size = event->header.size;
 220
 221         dump_printf("\n%p [%p]: event: %d\n",
 222                         (void *)(offset + head),
 223                         (void *)(long)event->header.size,
 224                         event->header.type);
 225
 226         if (!size || process_event(event, offset, head) < 0) {
 227
 228                 dump_printf("%p [%p]: skipping unknown header type: %d\n",
 229                         (void *)(offset + head),
 230                         (void *)(long)(event->header.size),
 231                         event->header.type);
 232
 233                 /*
 234                  * assume we lost track of the stream, check alignment, and
 235                  * increment a single u64 in the hope to catch on again 'soon'.
 236                  */
 237
 238                 if (unlikely(head & 7))
 239                         head &= ~7ULL;
 240
 241                 size = 8;
 242         }
 243
 244         head += size;
 245
 246         if (offset + head >= header->data_offset + header->data_size)
 247                 goto done;
 248
 249         if (offset + head < (unsigned long)input_stat.st_size)
 250                 goto more;
 251
 252 done:
 253         rc = EXIT_SUCCESS;
 254         close(input);
 255
 256         return rc;
 257 }
 258
 259