Commit | Line | Data |
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39ab7da2 JA |
1 | #include <unistd.h> |
2 | #include <math.h> | |
3 | #include <sys/time.h> | |
4 | #include <time.h> | |
5 | ||
6 | #include "fio.h" | |
7 | #include "smalloc.h" | |
8 | ||
5be4c944 | 9 | struct timeval *fio_tv = NULL; |
39ab7da2 | 10 | int fio_gtod_offload = 0; |
39ab7da2 | 11 | static pthread_t gtod_thread; |
8a2b393b | 12 | static os_cpu_mask_t fio_gtod_cpumask; |
39ab7da2 JA |
13 | |
14 | void fio_gtod_init(void) | |
15 | { | |
79c896a1 JA |
16 | if (fio_tv) |
17 | return; | |
18 | ||
39ab7da2 | 19 | fio_tv = smalloc(sizeof(struct timeval)); |
fba5c5ff JA |
20 | if (!fio_tv) |
21 | log_err("fio: smalloc pool exhausted\n"); | |
39ab7da2 JA |
22 | } |
23 | ||
24 | static void fio_gtod_update(void) | |
25 | { | |
27325ed5 JA |
26 | if (fio_tv) { |
27 | struct timeval __tv; | |
28 | ||
29 | gettimeofday(&__tv, NULL); | |
30 | fio_tv->tv_sec = __tv.tv_sec; | |
31 | write_barrier(); | |
32 | fio_tv->tv_usec = __tv.tv_usec; | |
33 | write_barrier(); | |
34 | } | |
39ab7da2 JA |
35 | } |
36 | ||
79c896a1 JA |
37 | struct gtod_cpu_data { |
38 | struct fio_mutex *mutex; | |
39 | unsigned int cpu; | |
40 | }; | |
41 | ||
39ab7da2 JA |
42 | static void *gtod_thread_main(void *data) |
43 | { | |
44 | struct fio_mutex *mutex = data; | |
45 | ||
79c896a1 | 46 | fio_setaffinity(gettid(), fio_gtod_cpumask); |
39ab7da2 JA |
47 | fio_mutex_up(mutex); |
48 | ||
49 | /* | |
50 | * As long as we have jobs around, update the clock. It would be nice | |
51 | * to have some way of NOT hammering that CPU with gettimeofday(), | |
52 | * but I'm not sure what to use outside of a simple CPU nop to relax | |
53 | * it - we don't want to lose precision. | |
54 | */ | |
55 | while (threads) { | |
56 | fio_gtod_update(); | |
57 | nop; | |
58 | } | |
59 | ||
60 | return NULL; | |
61 | } | |
62 | ||
63 | int fio_start_gtod_thread(void) | |
64 | { | |
65 | struct fio_mutex *mutex; | |
66 | pthread_attr_t attr; | |
67 | int ret; | |
68 | ||
69 | mutex = fio_mutex_init(FIO_MUTEX_LOCKED); | |
70 | if (!mutex) | |
71 | return 1; | |
72 | ||
73 | pthread_attr_init(&attr); | |
74 | pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN); | |
80fa0520 | 75 | ret = pthread_create(>od_thread, &attr, gtod_thread_main, mutex); |
39ab7da2 JA |
76 | pthread_attr_destroy(&attr); |
77 | if (ret) { | |
78 | log_err("Can't create gtod thread: %s\n", strerror(ret)); | |
79 | goto err; | |
80 | } | |
81 | ||
82 | ret = pthread_detach(gtod_thread); | |
83 | if (ret) { | |
84 | log_err("Can't detatch gtod thread: %s\n", strerror(ret)); | |
85 | goto err; | |
86 | } | |
87 | ||
88 | dprint(FD_MUTEX, "wait on startup_mutex\n"); | |
89 | fio_mutex_down(mutex); | |
90 | dprint(FD_MUTEX, "done waiting on startup_mutex\n"); | |
91 | err: | |
92 | fio_mutex_remove(mutex); | |
93 | return ret; | |
94 | } | |
95 | ||
79c896a1 JA |
96 | void fio_gtod_set_cpu(unsigned int cpu) |
97 | { | |
2a2f27b8 | 98 | #ifdef FIO_HAVE_CPU_AFFINITY |
79c896a1 | 99 | fio_cpu_set(&fio_gtod_cpumask, cpu); |
2a2f27b8 | 100 | #endif |
79c896a1 | 101 | } |