numam-dpdk/lib/vhost/rte_vhost_async.h
Jiayu Hu abeb865255 vhost: remove copy threshold for async path
Copy threshold has been introduced in async vhost data
path to select the appropriate copy engine to do copies
for higher efficiency.

However, it may cause packets ordering issues and also
introduces performance unpredictability.

Therefore, this patch removes copy threshold support in
async vhost data path.

Signed-off-by: Jiayu Hu <jiayu.hu@intel.com>
Signed-off-by: Cheng Jiang <cheng1.jiang@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2021-09-14 13:21:55 +02:00

260 lines
6.6 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2020 Intel Corporation
*/
#ifndef _RTE_VHOST_ASYNC_H_
#define _RTE_VHOST_ASYNC_H_
#include "rte_vhost.h"
/**
* iovec iterator
*/
struct rte_vhost_iov_iter {
/** offset to the first byte of interesting data */
size_t offset;
/** total bytes of data in this iterator */
size_t count;
/** pointer to the iovec array */
struct iovec *iov;
/** number of iovec in this iterator */
unsigned long nr_segs;
};
/**
* dma transfer descriptor pair
*/
struct rte_vhost_async_desc {
/** source memory iov_iter */
struct rte_vhost_iov_iter *src;
/** destination memory iov_iter */
struct rte_vhost_iov_iter *dst;
};
/**
* dma transfer status
*/
struct rte_vhost_async_status {
/** An array of application specific data for source memory */
uintptr_t *src_opaque_data;
/** An array of application specific data for destination memory */
uintptr_t *dst_opaque_data;
};
/**
* dma operation callbacks to be implemented by applications
*/
struct rte_vhost_async_channel_ops {
/**
* instruct async engines to perform copies for a batch of packets
*
* @param vid
* id of vhost device to perform data copies
* @param queue_id
* queue id to perform data copies
* @param descs
* an array of DMA transfer memory descriptors
* @param opaque_data
* opaque data pair sending to DMA engine
* @param count
* number of elements in the "descs" array
* @return
* number of descs processed, negative value means error
*/
int32_t (*transfer_data)(int vid, uint16_t queue_id,
struct rte_vhost_async_desc *descs,
struct rte_vhost_async_status *opaque_data,
uint16_t count);
/**
* check copy-completed packets from the async engine
* @param vid
* id of vhost device to check copy completion
* @param queue_id
* queue id to check copy completion
* @param opaque_data
* buffer to receive the opaque data pair from DMA engine
* @param max_packets
* max number of packets could be completed
* @return
* number of async descs completed, negative value means error
*/
int32_t (*check_completed_copies)(int vid, uint16_t queue_id,
struct rte_vhost_async_status *opaque_data,
uint16_t max_packets);
};
/**
* inflight async packet information
*/
struct async_inflight_info {
struct rte_mbuf *mbuf;
uint16_t descs; /* num of descs inflight */
uint16_t nr_buffers; /* num of buffers inflight for packed ring */
};
/**
* async channel features
*/
enum {
RTE_VHOST_ASYNC_INORDER = 1U << 0,
};
/**
* async channel configuration
*/
struct rte_vhost_async_config {
uint32_t features;
uint32_t rsvd[2];
};
/**
* Register an async channel for a vhost queue
*
* @param vid
* vhost device id async channel to be attached to
* @param queue_id
* vhost queue id async channel to be attached to
* @param config
* Async channel configuration structure
* @param ops
* Async channel operation callbacks
* @return
* 0 on success, -1 on failures
*/
__rte_experimental
int rte_vhost_async_channel_register(int vid, uint16_t queue_id,
struct rte_vhost_async_config config,
struct rte_vhost_async_channel_ops *ops);
/**
* Unregister an async channel for a vhost queue
*
* @param vid
* vhost device id async channel to be detached from
* @param queue_id
* vhost queue id async channel to be detached from
* @return
* 0 on success, -1 on failures
*/
__rte_experimental
int rte_vhost_async_channel_unregister(int vid, uint16_t queue_id);
/**
* Register an async channel for a vhost queue without performing any
* locking
*
* @note This function does not perform any locking, and is only safe to
* call in vhost callback functions.
*
* @param vid
* vhost device id async channel to be attached to
* @param queue_id
* vhost queue id async channel to be attached to
* @param config
* Async channel configuration
* @param ops
* Async channel operation callbacks
* @return
* 0 on success, -1 on failures
*/
__rte_experimental
int rte_vhost_async_channel_register_thread_unsafe(int vid, uint16_t queue_id,
struct rte_vhost_async_config config,
struct rte_vhost_async_channel_ops *ops);
/**
* Unregister an async channel for a vhost queue without performing any
* locking
*
* @note This function does not perform any locking, and is only safe to
* call in vhost callback functions.
*
* @param vid
* vhost device id async channel to be detached from
* @param queue_id
* vhost queue id async channel to be detached from
* @return
* 0 on success, -1 on failures
*/
__rte_experimental
int rte_vhost_async_channel_unregister_thread_unsafe(int vid,
uint16_t queue_id);
/**
* This function submits enqueue packets to async copy engine. Users
* need to poll transfer status by rte_vhost_poll_enqueue_completed()
* for successfully enqueued packets.
*
* @param vid
* id of vhost device to enqueue data
* @param queue_id
* queue id to enqueue data
* @param pkts
* array of packets to be enqueued
* @param count
* packets num to be enqueued
* @return
* num of packets enqueued
*/
__rte_experimental
uint16_t rte_vhost_submit_enqueue_burst(int vid, uint16_t queue_id,
struct rte_mbuf **pkts, uint16_t count);
/**
* This function checks async completion status for a specific vhost
* device queue. Packets which finish copying (enqueue) operation
* will be returned in an array.
*
* @param vid
* id of vhost device to enqueue data
* @param queue_id
* queue id to enqueue data
* @param pkts
* blank array to get return packet pointer
* @param count
* size of the packet array
* @return
* num of packets returned
*/
__rte_experimental
uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id,
struct rte_mbuf **pkts, uint16_t count);
/**
* This function returns the amount of in-flight packets for the vhost
* queue which uses async channel acceleration.
*
* @param vid
* id of vhost device to enqueue data
* @param queue_id
* queue id to enqueue data
* @return
* the amount of in-flight packets on success; -1 on failure
*/
__rte_experimental
int rte_vhost_async_get_inflight(int vid, uint16_t queue_id);
/**
* This function checks async completion status and clear packets for
* a specific vhost device queue. Packets which are inflight will be
* returned in an array.
*
* @note This function does not perform any locking
*
* @param vid
* ID of vhost device to clear data
* @param queue_id
* Queue id to clear data
* @param pkts
* Blank array to get return packet pointer
* @param count
* Size of the packet array
* @return
* Number of packets returned
*/
__rte_experimental
uint16_t rte_vhost_clear_queue_thread_unsafe(int vid, uint16_t queue_id,
struct rte_mbuf **pkts, uint16_t count);
#endif /* _RTE_VHOST_ASYNC_H_ */