Thread waitpid() error check
[fio.git] / time.c
1 #include <time.h>
2 #include <sys/time.h>
3
4 #include "fio.h"
5
6 static struct timeval genesis;
7 static unsigned long ns_granularity;
8
9 unsigned long utime_since(struct timeval *s, struct timeval *e)
10 {
11         long sec, usec;
12
13         sec = e->tv_sec - s->tv_sec;
14         usec = e->tv_usec - s->tv_usec;
15         if (sec > 0 && usec < 0) {
16                 sec--;
17                 usec += 1000000;
18         }
19
20         sec *= (double) 1000000;
21
22         return sec + usec;
23 }
24
25 unsigned long utime_since_now(struct timeval *s)
26 {
27         struct timeval t;
28
29         fio_gettime(&t, NULL);
30         return utime_since(s, &t);
31 }
32
33 unsigned long mtime_since(struct timeval *s, struct timeval *e)
34 {
35         long sec, usec;
36
37         sec = e->tv_sec - s->tv_sec;
38         usec = e->tv_usec - s->tv_usec;
39         if (sec > 0 && usec < 0) {
40                 sec--;
41                 usec += 1000000;
42         }
43
44         sec *= (double) 1000;
45         usec /= (double) 1000;
46
47         return sec + usec;
48 }
49
50 unsigned long mtime_since_now(struct timeval *s)
51 {
52         struct timeval t;
53         void *p = __builtin_return_address(0);
54
55         fio_gettime(&t, p);
56         return mtime_since(s, &t);
57 }
58
59 unsigned long time_since_now(struct timeval *s)
60 {
61         return mtime_since_now(s) / 1000;
62 }
63
64 /*
65  * busy looping version for the last few usec
66  */
67 void __usec_sleep(unsigned int usec)
68 {
69         struct timeval start;
70
71         fio_gettime(&start, NULL);
72         while (utime_since_now(&start) < usec)
73                 nop;
74 }
75
76 void usec_sleep(struct thread_data *td, unsigned long usec)
77 {
78         struct timespec req;
79         struct timeval tv;
80
81         do {
82                 unsigned long ts = usec;
83
84                 if (usec < ns_granularity) {
85                         __usec_sleep(usec);
86                         break;
87                 }
88
89                 ts = usec - ns_granularity;
90
91                 if (ts >= 1000000) {
92                         req.tv_sec = ts / 1000000;
93                         ts -= 1000000 * req.tv_sec;
94                 } else
95                         req.tv_sec = 0;
96
97                 req.tv_nsec = ts * 1000;
98                 fio_gettime(&tv, NULL);
99
100                 if (nanosleep(&req, NULL) < 0)
101                         break;
102
103                 ts = utime_since_now(&tv);
104                 if (ts >= usec)
105                         break;
106
107                 usec -= ts;
108         } while (!td->terminate);
109 }
110
111 void rate_throttle(struct thread_data *td, unsigned long time_spent,
112                    unsigned int bytes, int ddir)
113 {
114         unsigned long usec_cycle;
115
116         if (!td->rate)
117                 return;
118
119         usec_cycle = td->rate_usec_cycle * (bytes / td->min_bs[ddir]);
120
121         if (time_spent < usec_cycle) {
122                 unsigned long s = usec_cycle - time_spent;
123
124                 td->rate_pending_usleep += s;
125                 if (td->rate_pending_usleep >= 100000) {
126                         usec_sleep(td, td->rate_pending_usleep);
127                         td->rate_pending_usleep = 0;
128                 }
129         } else {
130                 long overtime = time_spent - usec_cycle;
131
132                 td->rate_pending_usleep -= overtime;
133         }
134 }
135
136 unsigned long mtime_since_genesis(void)
137 {
138         return mtime_since_now(&genesis);
139 }
140
141 static void fio_init time_init(void)
142 {
143         int i;
144
145         /*
146          * Check the granularity of the nanosleep function
147          */
148         for (i = 0; i < 10; i++) {
149                 struct timeval tv;
150                 struct timespec ts;
151                 unsigned long elapsed;
152
153                 fio_gettime(&tv, NULL);
154                 ts.tv_sec = 0;
155                 ts.tv_nsec = 1000;
156
157                 nanosleep(&ts, NULL);
158                 elapsed = utime_since_now(&tv);
159
160                 if (elapsed > ns_granularity)
161                         ns_granularity = elapsed;
162         }
163 }
164
165 void set_genesis_time(void)
166 {
167         fio_gettime(&genesis, NULL);
168 }
169
170 void fill_start_time(struct timeval *t)
171 {
172         memcpy(t, &genesis, sizeof(genesis));
173 }