4f6ec955c561cf49b9bfae3740f1c4968d51a0ff
[fio.git] / gettime.c
1 /*
2  * Clock functions
3  */
4
5 #include <unistd.h>
6 #include <sys/time.h>
7
8 #include "fio.h"
9 #include "os.h"
10
11 #include "hash.h"
12
13 static int clock_gettime_works = 0;
14
15 #ifdef FIO_DEBUG_TIME
16
17 #define HASH_BITS       8
18 #define HASH_SIZE       (1 << HASH_BITS)
19
20 static struct list_head hash[HASH_SIZE];
21 static int gtod_inited;
22
23 struct gtod_log {
24         struct list_head list;
25         void *caller;
26         unsigned long calls;
27 };
28
29 static struct gtod_log *find_hash(void *caller)
30 {
31         unsigned long h = hash_ptr(caller, HASH_BITS);
32         struct list_head *entry;
33
34         list_for_each(entry, &hash[h]) {
35                 struct gtod_log *log = list_entry(entry, struct gtod_log, 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_LIST_HEAD(&log->list);
53                 log->caller = caller;
54                 log->calls = 0;
55
56                 h = hash_ptr(caller, HASH_BITS);
57                 list_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 list_head *entry;
79                 struct gtod_log *log;
80
81                 list_for_each(entry, &hash[i]) {
82                         log = list_entry(entry, struct gtod_log, list);
83
84                         printf("function %p, calls %lu\n", log->caller, log->calls);
85                         total_calls += log->calls;
86                 }
87         }
88
89         printf("Total %lu gettimeofday\n", total_calls);
90 }
91
92 static void fio_init gtod_init(void)
93 {
94         int i;
95
96         for (i = 0; i < HASH_SIZE; i++)
97                 INIT_LIST_HEAD(&hash[i]);
98
99         gtod_inited = 1;
100 }
101
102 #endif /* FIO_DEBUG_TIME */
103
104 #ifdef FIO_DEBUG_TIME
105 void fio_gettime(struct timeval *tp, void *caller)
106 #else
107 void fio_gettime(struct timeval *tp, void fio_unused *caller)
108 #endif
109 {
110 #ifdef FIO_DEBUG_TIME
111         if (!caller)
112                 caller = __builtin_return_address(0);
113
114         gtod_log_caller(caller);
115 #endif
116         if (!clock_gettime_works) {
117 gtod:
118                 gettimeofday(tp, NULL);
119         } else {
120                 struct timespec ts;
121
122                 if (clock_gettime(CLOCK_MONOTONIC, &ts) < 0) {
123                         clock_gettime_works = 0;
124                         goto gtod;
125                 }
126
127                 tp->tv_sec = ts.tv_sec;
128                 tp->tv_usec = ts.tv_nsec / 1000;
129         }
130 }