From: "Liu, Yong" <yong.liu@intel.com>
To: "Fu, Patrick" <patrick.fu@intel.com>
Cc: "Fu, Patrick" <patrick.fu@intel.com>,
"Jiang, Cheng1" <cheng1.jiang@intel.com>,
"Liang, Cunming" <cunming.liang@intel.com>,
"dev@dpdk.org" <dev@dpdk.org>,
"maxime.coquelin@redhat.com" <maxime.coquelin@redhat.com>,
"Xia, Chenbo" <chenbo.xia@intel.com>,
"Wang, Zhihong" <zhihong.wang@intel.com>,
"Ye, Xiaolong" <xiaolong.ye@intel.com>
Subject: Re: [dpdk-dev] [PATCH v1 1/2] vhost: introduce async data path registration API
Date: Thu, 18 Jun 2020 05:50:51 +0000 [thread overview]
Message-ID: <86228AFD5BCD8E4EBFD2B90117B5E81E635F601B@SHSMSX103.ccr.corp.intel.com> (raw)
In-Reply-To: <1591869725-13331-2-git-send-email-patrick.fu@intel.com>
Thanks, Patrick. So comments are inline.
> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of patrick.fu@intel.com
> Sent: Thursday, June 11, 2020 6:02 PM
> To: dev@dpdk.org; maxime.coquelin@redhat.com; Xia, Chenbo
> <chenbo.xia@intel.com>; Wang, Zhihong <zhihong.wang@intel.com>; Ye,
> Xiaolong <xiaolong.ye@intel.com>
> Cc: Fu, Patrick <patrick.fu@intel.com>; Jiang, Cheng1
> <cheng1.jiang@intel.com>; Liang, Cunming <cunming.liang@intel.com>
> Subject: [dpdk-dev] [PATCH v1 1/2] vhost: introduce async data path
> registration API
>
> From: Patrick <patrick.fu@intel.com>
>
> This patch introduces registration/un-registration APIs
> for async data path together with all required data
> structures and DMA callback function proto-types.
>
> Signed-off-by: Patrick <patrick.fu@intel.com>
> ---
> lib/librte_vhost/Makefile | 3 +-
> lib/librte_vhost/rte_vhost.h | 1 +
> lib/librte_vhost/rte_vhost_async.h | 134
> +++++++++++++++++++++++++++++++++++++
> lib/librte_vhost/socket.c | 20 ++++++
> lib/librte_vhost/vhost.c | 74 +++++++++++++++++++-
> lib/librte_vhost/vhost.h | 30 ++++++++-
> lib/librte_vhost/vhost_user.c | 28 ++++++--
> 7 files changed, 283 insertions(+), 7 deletions(-)
> create mode 100644 lib/librte_vhost/rte_vhost_async.h
>
> diff --git a/lib/librte_vhost/Makefile b/lib/librte_vhost/Makefile
> index e592795..3aed094 100644
> --- a/lib/librte_vhost/Makefile
> +++ b/lib/librte_vhost/Makefile
> @@ -41,7 +41,8 @@ SRCS-$(CONFIG_RTE_LIBRTE_VHOST) := fd_man.c
> iotlb.c socket.c vhost.c \
> vhost_user.c virtio_net.c vdpa.c
>
> # install includes
> -SYMLINK-$(CONFIG_RTE_LIBRTE_VHOST)-include += rte_vhost.h rte_vdpa.h
> +SYMLINK-$(CONFIG_RTE_LIBRTE_VHOST)-include += rte_vhost.h rte_vdpa.h
> \
> + rte_vhost_async.h
>
Hi Patrick,
Please also update meson build for newly added file.
Thanks,
Marvin
> # only compile vhost crypto when cryptodev is enabled
> ifeq ($(CONFIG_RTE_LIBRTE_CRYPTODEV),y)
> diff --git a/lib/librte_vhost/rte_vhost.h b/lib/librte_vhost/rte_vhost.h
> index d43669f..cec4d07 100644
> --- a/lib/librte_vhost/rte_vhost.h
> +++ b/lib/librte_vhost/rte_vhost.h
> @@ -35,6 +35,7 @@
> #define RTE_VHOST_USER_EXTBUF_SUPPORT (1ULL << 5)
> /* support only linear buffers (no chained mbufs) */
> #define RTE_VHOST_USER_LINEARBUF_SUPPORT (1ULL << 6)
> +#define RTE_VHOST_USER_ASYNC_COPY (1ULL << 7)
>
> /** Protocol features. */
> #ifndef VHOST_USER_PROTOCOL_F_MQ
> diff --git a/lib/librte_vhost/rte_vhost_async.h
> b/lib/librte_vhost/rte_vhost_async.h
> new file mode 100644
> index 0000000..82f2ebe
> --- /dev/null
> +++ b/lib/librte_vhost/rte_vhost_async.h
> @@ -0,0 +1,134 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright(c) 2018 Intel Corporation
> + */
s/2018/2020/
> +
> +#ifndef _RTE_VHOST_ASYNC_H_
> +#define _RTE_VHOST_ASYNC_H_
> +
> +#include "rte_vhost.h"
> +
> +/**
> + * iovec iterator
> + */
> +struct iov_it {
> + /** 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;
> +};
Patrick,
I think structure named as "it" is too generic for understanding, please use more meaningful name like "iov_iter".
> +
> +/**
> + * dma transfer descriptor pair
> + */
> +struct dma_trans_desc {
> + /** source memory iov_it */
> + struct iov_it *src;
> + /** destination memory iov_it */
> + struct iov_it *dst;
> +};
> +
This series patch named as sync copy, and dma is just one async copy method which underneath hardware supplied.
IMHO, structure is better to named as "async_copy_desc" which matched the overall concept.
> +/**
> + * dma transfer status
> + */
> +struct dma_trans_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;
> +};
> +
Same as pervious comment.
> +/**
> + * dma operation callbacks to be implemented by applications
> + */
> +struct rte_vhost_async_channel_ops {
> + /**
> + * instruct a DMA channel 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
> + * -1 on failure, number of descs processed on success
> + */
> + int (*transfer_data)(int vid, uint16_t queue_id,
> + struct dma_trans_desc *descs,
> + struct dma_trans_status *opaque_data,
> + uint16_t count);
> + /**
> + * check copy-completed packets from a DMA channel
> + * @param vid
> + * id of vhost device to check copy completion
> + * @param queue_id
> + * queue id to check copyp 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
> + * -1 on failure, number of iov segments completed on success
> + */
> + int (*check_completed_copies)(int vid, uint16_t queue_id,
> + struct dma_trans_status *opaque_data,
> + uint16_t max_packets);
> +};
> +
> +/**
> + * dma channel feature bit definition
> + */
> +struct dma_channel_features {
> + union {
> + uint32_t intval;
> + struct {
> + uint32_t inorder:1;
> + uint32_t resvd0115:15;
> + uint32_t threshold:12;
> + uint32_t resvd2831:4;
> + };
> + };
> +};
> +
Naming feature bits as "intval" may cause confusion, why not just use its meaning like "engine_features"?
I'm not sure whether format "resvd0115" match dpdk copy style. In my mind, dpdk will use resvd_0 and resvd_1 for two reserved elements.
> +/**
> + * register a dma channel for vhost
> + *
> + * @param vid
> + * vhost device id DMA channel to be attached to
> + * @param queue_id
> + * vhost queue id DMA channel to be attached to
> + * @param features
> + * DMA channel feature bit
> + * b0 : DMA supports inorder data transfer
> + * b1 - b15: reserved
> + * b16 - b27: Packet length threshold for DMA transfer
> + * b28 - b31: reserved
> + * @param ops
> + * DMA operation callbacks
> + * @return
> + * 0 on success, -1 on failures
> + */
> +int rte_vhost_async_channel_register(int vid, uint16_t queue_id,
> + uint32_t features, struct rte_vhost_async_channel_ops *ops);
> +
> +/**
> + * unregister a dma channel for vhost
> + *
> + * @param vid
> + * vhost device id DMA channel to be detached
> + * @param queue_id
> + * vhost queue id DMA channel to be detached
> + * @return
> + * 0 on success, -1 on failures
> + */
> +int rte_vhost_async_channel_unregister(int vid, uint16_t queue_id);
> +
> +#endif /* _RTE_VDPA_H_ */
> diff --git a/lib/librte_vhost/socket.c b/lib/librte_vhost/socket.c
> index 0a66ef9..f817783 100644
> --- a/lib/librte_vhost/socket.c
> +++ b/lib/librte_vhost/socket.c
> @@ -42,6 +42,7 @@ struct vhost_user_socket {
> bool use_builtin_virtio_net;
> bool extbuf;
> bool linearbuf;
> + bool async_copy;
>
> /*
> * The "supported_features" indicates the feature bits the
> @@ -210,6 +211,7 @@ struct vhost_user {
> size_t size;
> struct vhost_user_connection *conn;
> int ret;
> + struct virtio_net *dev;
>
> if (vsocket == NULL)
> return;
> @@ -241,6 +243,13 @@ struct vhost_user {
> if (vsocket->linearbuf)
> vhost_enable_linearbuf(vid);
>
> + if (vsocket->async_copy) {
> + dev = get_device(vid);
> +
> + if (dev)
> + dev->async_copy = 1;
> + }
> +
IMHO, user can chose which queue utilize async copy as backend hardware resource is limited.
So should async_copy enable flag be saved in virtqueue structure?
> VHOST_LOG_CONFIG(INFO, "new device, handle is %d\n", vid);
>
> if (vsocket->notify_ops->new_connection) {
> @@ -891,6 +900,17 @@ struct vhost_user_reconnect_list {
> goto out_mutex;
> }
>
> + vsocket->async_copy = flags & RTE_VHOST_USER_ASYNC_COPY;
> +
> + if (vsocket->async_copy &&
> + (flags & (RTE_VHOST_USER_IOMMU_SUPPORT |
> + RTE_VHOST_USER_POSTCOPY_SUPPORT))) {
> + VHOST_LOG_CONFIG(ERR, "error: enabling async copy and
> IOMMU "
> + "or post-copy feature simultaneously is not "
> + "supported\n");
> + goto out_mutex;
> + }
> +
> /*
> * Set the supported features correctly for the builtin vhost-user
> * net driver.
> diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
> index 0266318..e6b688a 100644
> --- a/lib/librte_vhost/vhost.c
> +++ b/lib/librte_vhost/vhost.c
> @@ -332,8 +332,13 @@
> {
> if (vq_is_packed(dev))
> rte_free(vq->shadow_used_packed);
> - else
> + else {
> rte_free(vq->shadow_used_split);
> + if (vq->async_pkts_pending)
> + rte_free(vq->async_pkts_pending);
> + if (vq->async_pending_info)
> + rte_free(vq->async_pending_info);
> + }
> rte_free(vq->batch_copy_elems);
> rte_mempool_free(vq->iotlb_pool);
> rte_free(vq);
> @@ -1527,3 +1532,70 @@ int rte_vhost_extern_callback_register(int vid,
> if (vhost_data_log_level >= 0)
> rte_log_set_level(vhost_data_log_level,
> RTE_LOG_WARNING);
> }
> +
> +int rte_vhost_async_channel_register(int vid, uint16_t queue_id,
> + uint32_t features,
> + struct rte_vhost_async_channel_ops
> *ops)
> +{
> + struct vhost_virtqueue *vq;
> + struct virtio_net *dev = get_device(vid);
> + struct dma_channel_features f;
> +
> + if (dev == NULL || ops == NULL)
> + return -1;
> +
> + f.intval = features;
> +
> + vq = dev->virtqueue[queue_id];
> +
> + if (vq == NULL)
> + return -1;
> +
> + /** packed queue is not supported */
> + if (vq_is_packed(dev) || !f.inorder)
> + return -1;
> +
Virtio already has in_order concept, these two names are so like and can be easily messed up. Please consider how to distinguish them.
> + if (ops->check_completed_copies == NULL ||
> + ops->transfer_data == NULL)
> + return -1;
> +
Previous error is unlikely to be true, unlikely macro may be helpful for understanding.
> + rte_spinlock_lock(&vq->access_lock);
> +
> + vq->async_ops.check_completed_copies = ops-
> >check_completed_copies;
> + vq->async_ops.transfer_data = ops->transfer_data;
> +
> + vq->async_inorder = f.inorder;
> + vq->async_threshold = f.threshold;
> +
> + vq->async_registered = true;
> +
> + rte_spinlock_unlock(&vq->access_lock);
> +
> + return 0;
> +}
> +
> +int rte_vhost_async_channel_unregister(int vid, uint16_t queue_id)
> +{
> + struct vhost_virtqueue *vq;
> + struct virtio_net *dev = get_device(vid);
> +
> + if (dev == NULL)
> + return -1;
> +
> + vq = dev->virtqueue[queue_id];
> +
> + if (vq == NULL)
> + return -1;
> +
> + rte_spinlock_lock(&vq->access_lock);
> +
> + vq->async_ops.transfer_data = NULL;
> + vq->async_ops.check_completed_copies = NULL;
> +
> + vq->async_registered = false;
> +
> + rte_spinlock_unlock(&vq->access_lock);
> +
> + return 0;
> +}
> +
> diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
> index df98d15..a7fbe23 100644
> --- a/lib/librte_vhost/vhost.h
> +++ b/lib/librte_vhost/vhost.h
> @@ -23,6 +23,8 @@
> #include "rte_vhost.h"
> #include "rte_vdpa.h"
>
> +#include "rte_vhost_async.h"
> +
> /* Used to indicate that the device is running on a data core */
> #define VIRTIO_DEV_RUNNING 1
> /* Used to indicate that the device is ready to operate */
> @@ -39,6 +41,11 @@
>
> #define VHOST_LOG_CACHE_NR 32
>
> +#define MAX_PKT_BURST 32
> +
> +#define VHOST_MAX_ASYNC_IT (MAX_PKT_BURST * 2)
> +#define VHOST_MAX_ASYNC_VEC (BUF_VECTOR_MAX * 2)
> +
> #define PACKED_DESC_ENQUEUE_USED_FLAG(w) \
> ((w) ? (VRING_DESC_F_AVAIL | VRING_DESC_F_USED |
> VRING_DESC_F_WRITE) : \
> VRING_DESC_F_WRITE)
> @@ -200,6 +207,25 @@ struct vhost_virtqueue {
> TAILQ_HEAD(, vhost_iotlb_entry) iotlb_list;
> int iotlb_cache_nr;
> TAILQ_HEAD(, vhost_iotlb_entry) iotlb_pending_list;
> +
> + /* operation callbacks for async dma */
> + struct rte_vhost_async_channel_ops async_ops;
> +
> + struct iov_it it_pool[VHOST_MAX_ASYNC_IT];
> + struct iovec vec_pool[VHOST_MAX_ASYNC_VEC];
> +
> + /* async data transfer status */
> + uintptr_t **async_pkts_pending;
> + #define ASYNC_PENDING_INFO_N_MSK 0xFFFF
> + #define ASYNC_PENDING_INFO_N_SFT 16
> + uint64_t *async_pending_info;
> + uint16_t async_pkts_idx;
> + uint16_t async_pkts_inflight_n;
> +
> + /* vq async features */
> + bool async_inorder;
> + bool async_registered;
> + uint16_t async_threshold;
> } __rte_cache_aligned;
>
> /* Old kernels have no such macros defined */
> @@ -353,6 +379,7 @@ struct virtio_net {
> int16_t broadcast_rarp;
> uint32_t nr_vring;
> int dequeue_zero_copy;
> + int async_copy;
> int extbuf;
> int linearbuf;
> struct vhost_virtqueue *virtqueue[VHOST_MAX_QUEUE_PAIRS * 2];
> @@ -702,7 +729,8 @@ uint64_t translate_log_addr(struct virtio_net *dev,
> struct vhost_virtqueue *vq,
> /* Don't kick guest if we don't reach index specified by guest. */
> if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX)) {
> uint16_t old = vq->signalled_used;
> - uint16_t new = vq->last_used_idx;
> + uint16_t new = vq->async_pkts_inflight_n ?
> + vq->used->idx:vq->last_used_idx;
> bool signalled_used_valid = vq->signalled_used_valid;
>
> vq->signalled_used = new;
> diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
> index 84bebad..d7600bf 100644
> --- a/lib/librte_vhost/vhost_user.c
> +++ b/lib/librte_vhost/vhost_user.c
> @@ -464,12 +464,25 @@
> } else {
> if (vq->shadow_used_split)
> rte_free(vq->shadow_used_split);
> + if (vq->async_pkts_pending)
> + rte_free(vq->async_pkts_pending);
> + if (vq->async_pending_info)
> + rte_free(vq->async_pending_info);
> +
> vq->shadow_used_split = rte_malloc(NULL,
> vq->size * sizeof(struct vring_used_elem),
> RTE_CACHE_LINE_SIZE);
> - if (!vq->shadow_used_split) {
> + vq->async_pkts_pending = rte_malloc(NULL,
> + vq->size * sizeof(uintptr_t),
> + RTE_CACHE_LINE_SIZE);
> + vq->async_pending_info = rte_malloc(NULL,
> + vq->size * sizeof(uint64_t),
> + RTE_CACHE_LINE_SIZE);
> + if (!vq->shadow_used_split ||
> + !vq->async_pkts_pending ||
> + !vq->async_pending_info) {
> VHOST_LOG_CONFIG(ERR,
> - "failed to allocate memory for
> shadow used ring.\n");
> + "failed to allocate memory for vq
> internal data.\n");
If async copy not enabled, there will be no need to allocate related structures.
> return RTE_VHOST_MSG_RESULT_ERR;
> }
> }
> @@ -1147,7 +1160,8 @@
> goto err_mmap;
> }
>
> - populate = (dev->dequeue_zero_copy) ? MAP_POPULATE : 0;
> + populate = (dev->dequeue_zero_copy || dev->async_copy) ?
> + MAP_POPULATE : 0;
> mmap_addr = mmap(NULL, mmap_size, PROT_READ |
> PROT_WRITE,
> MAP_SHARED | populate, fd, 0);
>
> @@ -1162,7 +1176,7 @@
> reg->host_user_addr = (uint64_t)(uintptr_t)mmap_addr +
> mmap_offset;
>
> - if (dev->dequeue_zero_copy)
> + if (dev->dequeue_zero_copy || dev->async_copy)
> if (add_guest_pages(dev, reg, alignment) < 0) {
> VHOST_LOG_CONFIG(ERR,
> "adding guest pages to region %u
> failed.\n",
> @@ -1945,6 +1959,12 @@ static int vhost_user_set_vring_err(struct
> virtio_net **pdev __rte_unused,
> } else {
> rte_free(vq->shadow_used_split);
> vq->shadow_used_split = NULL;
> + if (vq->async_pkts_pending)
> + rte_free(vq->async_pkts_pending);
> + if (vq->async_pending_info)
> + rte_free(vq->async_pending_info);
> + vq->async_pkts_pending = NULL;
> + vq->async_pending_info = NULL;
> }
>
> rte_free(vq->batch_copy_elems);
> --
> 1.8.3.1
next prev parent reply other threads:[~2020-06-18 5:51 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-11 10:02 [dpdk-dev] [PATCH v1 0/2] introduce asynchronous data path for vhost patrick.fu
2020-06-11 10:02 ` [dpdk-dev] [PATCH v1 1/2] vhost: introduce async data path registration API patrick.fu
2020-06-18 5:50 ` Liu, Yong [this message]
2020-06-18 9:08 ` Fu, Patrick
2020-06-19 0:40 ` Liu, Yong
2020-06-25 13:42 ` Maxime Coquelin
2020-06-26 14:28 ` Maxime Coquelin
2020-06-29 1:15 ` Fu, Patrick
2020-06-26 14:44 ` Maxime Coquelin
2020-06-11 10:02 ` [dpdk-dev] [PATCH v1 2/2] vhost: introduce async enqueue for split ring patrick.fu
2020-06-18 6:56 ` Liu, Yong
2020-06-18 11:36 ` Fu, Patrick
2020-06-26 14:39 ` Maxime Coquelin
2020-06-26 14:46 ` Maxime Coquelin
2020-06-29 1:25 ` Fu, Patrick
2020-06-26 14:42 ` [dpdk-dev] [PATCH v1 0/2] introduce asynchronous data path for vhost Maxime Coquelin
2020-07-03 10:27 ` [dpdk-dev] [PATCH v3 " patrick.fu
2020-07-03 10:27 ` [dpdk-dev] [PATCH v3 1/2] vhost: introduce async enqueue registration API patrick.fu
2020-07-03 10:27 ` [dpdk-dev] [PATCH v3 2/2] vhost: introduce async enqueue for split ring patrick.fu
2020-07-03 12:21 ` [dpdk-dev] [PATCH v4 0/2] introduce asynchronous data path for vhost patrick.fu
2020-07-03 12:21 ` [dpdk-dev] [PATCH v4 1/2] vhost: introduce async enqueue registration API patrick.fu
2020-07-06 3:05 ` Liu, Yong
2020-07-06 9:08 ` Fu, Patrick
2020-07-03 12:21 ` [dpdk-dev] [PATCH v4 2/2] vhost: introduce async enqueue for split ring patrick.fu
2020-07-06 11:53 ` [dpdk-dev] [PATCH v5 0/2] introduce asynchronous data path for vhost patrick.fu
2020-07-06 11:53 ` [dpdk-dev] [PATCH v5 1/2] vhost: introduce async enqueue registration API patrick.fu
2020-07-06 11:53 ` [dpdk-dev] [PATCH v5 2/2] vhost: introduce async enqueue for split ring patrick.fu
2020-07-07 5:07 ` [dpdk-dev] [PATCH v6 0/2] introduce asynchronous data path for vhost patrick.fu
2020-07-07 5:07 ` [dpdk-dev] [PATCH v6 1/2] vhost: introduce async enqueue registration API patrick.fu
2020-07-07 8:22 ` Xia, Chenbo
2020-07-07 5:07 ` [dpdk-dev] [PATCH v6 2/2] vhost: introduce async enqueue for split ring patrick.fu
2020-07-07 8:22 ` Xia, Chenbo
2020-07-07 16:45 ` [dpdk-dev] [PATCH v6 0/2] introduce asynchronous data path for vhost Ferruh Yigit
2020-07-20 13:26 ` Maxime Coquelin
2020-07-21 2:28 ` Fu, Patrick
2020-07-21 8:28 ` Maxime Coquelin
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