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 int mmap_dispatch_perf_file(struct perf_header **pheader,
  74                             const char *input_name,
  75                             int force,
  76                             int full_paths,
  77                             int *cwdlen,
  78                             char **cwd)
  79 {
  80         int ret, rc = EXIT_FAILURE;
  81         struct perf_header *header;
  82         unsigned long head, shift;
  83         unsigned long offset = 0;
  84         struct stat input_stat;
  85         size_t  page_size;
  86         u64 sample_type;
  87         event_t *event;
  88         uint32_t size;
  89         int input;
  90         char *buf;
  91
  92         if (!curr_handler)
  93                 die("Forgot to register perf file handler");
  94
  95         page_size = getpagesize();
  96
  97         input = open(input_name, O_RDONLY);
  98         if (input < 0) {
  99                 fprintf(stderr, " failed to open file: %s", input_name);
 100                 if (!strcmp(input_name, "perf.data"))
 101                         fprintf(stderr, "  (try 'perf record' first)");
 102                 fprintf(stderr, "\n");
 103                 exit(-1);
 104         }
 105
 106         ret = fstat(input, &input_stat);
 107         if (ret < 0) {
 108                 perror("failed to stat file");
 109                 exit(-1);
 110         }
 111
 112         if (!force && input_stat.st_uid && (input_stat.st_uid != geteuid())) {
 113                 fprintf(stderr, "file: %s not owned by current user or root\n",
 114                         input_name);
 115                 exit(-1);
 116         }
 117
 118         if (!input_stat.st_size) {
 119                 fprintf(stderr, "zero-sized file, nothing to do!\n");
 120                 exit(0);
 121         }
 122
 123         *pheader = perf_header__read(input);
 124         header = *pheader;
 125         head = header->data_offset;
 126
 127         sample_type = perf_header__sample_type(header);
 128
 129         if (curr_handler->sample_type_check)
 130                 if (curr_handler->sample_type_check(sample_type) < 0)
 131                         exit(-1);
 132
 133         if (load_kernel() < 0) {
 134                 perror("failed to load kernel symbols");
 135                 return EXIT_FAILURE;
 136         }
 137
 138         if (!full_paths) {
 139                 if (getcwd(__cwd, sizeof(__cwd)) == NULL) {
 140                         perror("failed to get the current directory");
 141                         return EXIT_FAILURE;
 142                 }
 143                 *cwd = __cwd;
 144                 *cwdlen = strlen(*cwd);
 145         } else {
 146                 *cwd = NULL;
 147                 *cwdlen = 0;
 148         }
 149
 150         shift = page_size * (head / page_size);
 151         offset += shift;
 152         head -= shift;
 153
 154 remap:
 155         buf = (char *)mmap(NULL, page_size * mmap_window, PROT_READ,
 156                            MAP_SHARED, input, offset);
 157         if (buf == MAP_FAILED) {
 158                 perror("failed to mmap file");
 159                 exit(-1);
 160         }
 161
 162 more:
 163         event = (event_t *)(buf + head);
 164
 165         size = event->header.size;
 166         if (!size)
 167                 size = 8;
 168
 169         if (head + event->header.size >= page_size * mmap_window) {
 170                 int munmap_ret;
 171
 172                 shift = page_size * (head / page_size);
 173
 174                 munmap_ret = munmap(buf, page_size * mmap_window);
 175                 assert(munmap_ret == 0);
 176
 177                 offset += shift;
 178                 head -= shift;
 179                 goto remap;
 180         }
 181
 182         size = event->header.size;
 183
 184         dump_printf("\n%p [%p]: event: %d\n",
 185                         (void *)(offset + head),
 186                         (void *)(long)event->header.size,
 187                         event->header.type);
 188
 189         if (!size || process_event(event, offset, head) < 0) {
 190
 191                 dump_printf("%p [%p]: skipping unknown header type: %d\n",
 192                         (void *)(offset + head),
 193                         (void *)(long)(event->header.size),
 194                         event->header.type);
 195
 196                 /*
 197                  * assume we lost track of the stream, check alignment, and
 198                  * increment a single u64 in the hope to catch on again 'soon'.
 199                  */
 200
 201                 if (unlikely(head & 7))
 202                         head &= ~7ULL;
 203
 204                 size = 8;
 205         }
 206
 207         head += size;
 208
 209         if (offset + head >= header->data_offset + header->data_size)
 210                 goto done;
 211
 212         if (offset + head < (unsigned long)input_stat.st_size)
 213                 goto more;
 214
 215 done:
 216         rc = EXIT_SUCCESS;
 217         close(input);
 218
 219         return rc;
 220 }
 221
 222