Engines should not touch nr_open_files anymore
[fio.git] / engines / null.c
CommitLineData
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1/*
2 * null engine - doesn't do any transfers. Used to test fio.
3 *
4 */
5#include <stdio.h>
6#include <stdlib.h>
7#include <unistd.h>
8#include <errno.h>
9#include <assert.h>
10
11#include "../fio.h"
12#include "../os.h"
13
36167d82 14static int fio_null_queue(struct thread_data fio_unused *td, struct io_u *io_u)
a94ea28b 15{
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16 io_u->resid = 0;
17 io_u->error = 0;
36167d82 18 return FIO_Q_COMPLETED;
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19}
20
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21static int fio_null_setup(struct thread_data *td)
22{
23 struct fio_file *f;
24 int i;
25
26 if (!td->total_file_size) {
27 log_err("fio: need size= set\n");
28 return 1;
29 }
30
31 td->io_size = td->total_file_size;
32 td->total_io_size = td->io_size;
33
34 for_each_file(td, f, i) {
35 f->fd = dup(STDOUT_FILENO);
36 f->real_file_size = td->total_io_size / td->nr_files;
37 f->file_size = f->real_file_size;
38 }
39
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40 return 0;
41}
42
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43static int fio_null_open(struct thread_data fio_unused *td,
44 struct fio_file fio_unused *f)
45{
46 return 0;
47}
48
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49static struct ioengine_ops ioengine = {
50 .name = "null",
51 .version = FIO_IOOPS_VERSION,
2fd233b7 52 .setup = fio_null_setup,
a94ea28b 53 .queue = fio_null_queue,
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54 .open_file = fio_null_open,
55 .flags = FIO_SYNCIO | FIO_DISKLESSIO,
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56};
57
58static void fio_init fio_null_register(void)
59{
60 register_ioengine(&ioengine);
61}
62
63static void fio_exit fio_null_unregister(void)
64{
65 unregister_ioengine(&ioengine);
66}