gettime.c

   1 /*
   2  * Clock functions
   3  */
   4
   5 #include <unistd.h>
   6 #include <sys/time.h>
   7
   8 #include "fio.h"
   9
  10 #include "hash.h"
  11
  12 static int clock_gettime_works;
  13
  14 #ifdef FIO_DEBUG_TIME
  15
  16 #define HASH_BITS       8
  17 #define HASH_SIZE       (1 << HASH_BITS)
  18
  19 static struct flist_head hash[HASH_SIZE];
  20 static int gtod_inited;
  21
  22 struct gtod_log {
  23         struct flist_head list;
  24         void *caller;
  25         unsigned long calls;
  26 };
  27
  28 static struct gtod_log *find_hash(void *caller)
  29 {
  30         unsigned long h = hash_ptr(caller, HASH_BITS);
  31         struct flist_head *entry;
  32
  33         flist_for_each(entry, &hash[h]) {
  34                 struct gtod_log *log = flist_entry(entry, struct gtod_log,
  35                                                                         list);
  36
  37                 if (log->caller == caller)
  38                         return log;
  39         }
  40
  41         return NULL;
  42 }
  43
  44 static struct gtod_log *find_log(void *caller)
  45 {
  46         struct gtod_log *log = find_hash(caller);
  47
  48         if (!log) {
  49                 unsigned long h;
  50
  51                 log = malloc(sizeof(*log));
  52                 INIT_FLIST_HEAD(&log->list);
  53                 log->caller = caller;
  54                 log->calls = 0;
  55
  56                 h = hash_ptr(caller, HASH_BITS);
  57                 flist_add_tail(&log->list, &hash[h]);
  58         }
  59
  60         return log;
  61 }
  62
  63 static void gtod_log_caller(void *caller)
  64 {
  65         if (gtod_inited) {
  66                 struct gtod_log *log = find_log(caller);
  67
  68                 log->calls++;
  69         }
  70 }
  71
  72 static void fio_exit fio_dump_gtod(void)
  73 {
  74         unsigned long total_calls = 0;
  75         int i;
  76
  77         for (i = 0; i < HASH_SIZE; i++) {
  78                 struct flist_head *entry;
  79                 struct gtod_log *log;
  80
  81                 flist_for_each(entry, &hash[i]) {
  82                         log = flist_entry(entry, struct gtod_log, list);
  83
  84                         printf("function %p, calls %lu\n", log->caller,
  85                                                                 log->calls);
  86                         total_calls += log->calls;
  87                 }
  88         }
  89
  90         printf("Total %lu gettimeofday\n", total_calls);
  91 }
  92
  93 static void fio_init gtod_init(void)
  94 {
  95         int i;
  96
  97         for (i = 0; i < HASH_SIZE; i++)
  98                 INIT_FLIST_HEAD(&hash[i]);
  99
 100         gtod_inited = 1;
 101 }
 102
 103 #endif /* FIO_DEBUG_TIME */
 104
 105 #ifdef FIO_DEBUG_TIME
 106 void fio_gettime(struct timeval *tp, void *caller)
 107 #else
 108 void fio_gettime(struct timeval *tp, void fio_unused *caller)
 109 #endif
 110 {
 111 #ifdef FIO_DEBUG_TIME
 112         if (!caller)
 113                 caller = __builtin_return_address(0);
 114
 115         gtod_log_caller(caller);
 116 #endif
 117         if (!clock_gettime_works) {
 118 gtod:
 119                 gettimeofday(tp, NULL);
 120         } else {
 121                 struct timespec ts;
 122
 123                 if (clock_gettime(CLOCK_MONOTONIC, &ts) < 0) {
 124                         clock_gettime_works = 0;
 125                         goto gtod;
 126                 }
 127
 128                 tp->tv_sec = ts.tv_sec;
 129                 tp->tv_usec = ts.tv_nsec / 1000;
 130         }
 131 }