xref: /spdk/module/bdev/delay/vbdev_delay.h (revision b30d57cdad6d2bc75cc1e4e2ebbcebcb0d98dcfa)
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33 
34 #ifndef SPDK_VBDEV_DELAY_H
35 #define SPDK_VBDEV_DELAY_H
36 
37 #include "spdk/stdinc.h"
38 
39 #include "spdk/bdev.h"
40 #include "spdk/bdev_module.h"
41 
42 enum delay_io_type {
43 	DELAY_AVG_READ,
44 	DELAY_P99_READ,
45 	DELAY_AVG_WRITE,
46 	DELAY_P99_WRITE,
47 	DELAY_NONE
48 };
49 
50 /**
51  * Create new delay bdev.
52  *
53  * \param bdev_name Bdev on which delay vbdev will be created.
54  * \param vbdev_name Name of the delay bdev.
55  * \param avg_read_latency Desired typical read latency.
56  * \param p99_read_latency Desired p99 read latency
57  * \param avg_write_latency Desired typical write latency.
58  * \param p99_write_latency Desired p99 write latency
59  * \return 0 on success, other on failure.
60  */
61 int create_delay_disk(const char *bdev_name, const char *vbdev_name, uint64_t avg_read_latency,
62 		      uint64_t p99_read_latency, uint64_t avg_write_latency, uint64_t p99_write_latency);
63 
64 /**
65  * Delete delay bdev.
66  *
67  * \param bdev Pointer to delay bdev.
68  * \param cb_fn Function to call after deletion.
69  * \param cb_arg Argument to pass to cb_fn.
70  */
71 void delete_delay_disk(struct spdk_bdev *bdev, spdk_bdev_unregister_cb cb_fn,
72 		       void *cb_arg);
73 
74 /**
75  * Update one of the latency values for a given delay bdev.
76  *
77  * \param delay_name The name of the delay bdev
78  * \param latency_us The new latency value, in microseconds
79  * \param type a valid value from the delay_io_type enum
80  * \return 0 on success, -ENODEV if the bdev cannot be found, and -EINVAL if the bdev is not a delay device.
81  */
82 int vbdev_delay_update_latency_value(char *delay_name, uint64_t latency_us,
83 				     enum delay_io_type type);
84 
85 #endif /* SPDK_VBDEV_DELAY_H */
86