From: Patrick Fu <patrick.fu@intel.com> Vhost async enqueue assumes that all async copies should break at packet boundary. i.e. if a packet is splited into multiple copy segments, the async engine should always report copy completion when entire packet is finished. This patch removes the assumption. Fixes: cd6760da1076 ("vhost: introduce async enqueue for split ring") Signed-off-by: Patrick Fu <patrick.fu@intel.com> --- lib/librte_vhost/vhost.h | 3 +++ lib/librte_vhost/virtio_net.c | 12 ++++++++---- 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h index 8c01cee42..0f7212f88 100644 --- a/lib/librte_vhost/vhost.h +++ b/lib/librte_vhost/vhost.h @@ -46,6 +46,8 @@ #define MAX_PKT_BURST 32 +#define ASYNC_MAX_POLL_SEG 255 + #define VHOST_MAX_ASYNC_IT (MAX_PKT_BURST * 2) #define VHOST_MAX_ASYNC_VEC (BUF_VECTOR_MAX * 2) @@ -225,6 +227,7 @@ struct vhost_virtqueue { uint64_t *async_pending_info; uint16_t async_pkts_idx; uint16_t async_pkts_inflight_n; + uint16_t async_last_seg_n; /* vq async features */ bool async_inorder; diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c index 1d0be3dd4..c6fa33f37 100644 --- a/lib/librte_vhost/virtio_net.c +++ b/lib/librte_vhost/virtio_net.c @@ -1652,12 +1652,14 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id, start_idx = virtio_dev_rx_async_get_info_idx(pkts_idx, vq_size, vq->async_pkts_inflight_n); - n_pkts_cpl = - vq->async_ops.check_completed_copies(vid, queue_id, 0, count); + n_pkts_cpl = vq->async_ops.check_completed_copies(vid, queue_id, + 0, ASYNC_MAX_POLL_SEG - vq->async_last_seg_n) + + vq->async_last_seg_n; rte_smp_wmb(); - while (likely(((start_idx + n_pkts_put) & (vq_size - 1)) != pkts_idx)) { + while (likely((n_pkts_put < count) && + (((start_idx + n_pkts_put) & (vq_size - 1)) != pkts_idx))) { uint64_t info = async_pending_info[ (start_idx + n_pkts_put) & (vq_size - 1)]; uint64_t n_segs; @@ -1666,7 +1668,7 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id, n_segs = info >> ASYNC_PENDING_INFO_N_SFT; if (n_segs) { - if (!n_pkts_cpl || n_pkts_cpl < n_segs) { + if (unlikely(n_pkts_cpl < n_segs)) { n_pkts_put--; n_descs -= info & ASYNC_PENDING_INFO_N_MSK; if (n_pkts_cpl) { @@ -1684,6 +1686,8 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id, } } + vq->async_last_seg_n = n_pkts_cpl; + if (n_pkts_put) { vq->async_pkts_inflight_n -= n_pkts_put; __atomic_add_fetch(&vq->used->idx, n_descs, __ATOMIC_RELEASE); -- 2.18.4
From: Patrick Fu <patrick.fu@intel.com> Vhost async enqueue assumes that all async copies should break at packet boundary. i.e. if a packet is splited into multiple copy segments, the async engine should always report copy completion when entire packet is finished. This patch removes the assumption. Fixes: cd6760da1076 ("vhost: introduce async enqueue for split ring") Signed-off-by: Patrick Fu <patrick.fu@intel.com> --- v2: - fix an issue that can stuck async poll when packets buffer is full - rename a local variable to better reflect its usage lib/librte_vhost/vhost.h | 3 +++ lib/librte_vhost/virtio_net.c | 17 ++++++++++++----- 2 files changed, 15 insertions(+), 5 deletions(-) diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h index 8c01cee42..0f7212f88 100644 --- a/lib/librte_vhost/vhost.h +++ b/lib/librte_vhost/vhost.h @@ -46,6 +46,8 @@ #define MAX_PKT_BURST 32 +#define ASYNC_MAX_POLL_SEG 255 + #define VHOST_MAX_ASYNC_IT (MAX_PKT_BURST * 2) #define VHOST_MAX_ASYNC_VEC (BUF_VECTOR_MAX * 2) @@ -225,6 +227,7 @@ struct vhost_virtqueue { uint64_t *async_pending_info; uint16_t async_pkts_idx; uint16_t async_pkts_inflight_n; + uint16_t async_last_seg_n; /* vq async features */ bool async_inorder; diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c index 1d0be3dd4..17808ab29 100644 --- a/lib/librte_vhost/virtio_net.c +++ b/lib/librte_vhost/virtio_net.c @@ -1633,6 +1633,7 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id, struct vhost_virtqueue *vq; uint16_t n_pkts_cpl, n_pkts_put = 0, n_descs = 0; uint16_t start_idx, pkts_idx, vq_size; + uint16_t n_inflight; uint64_t *async_pending_info; VHOST_LOG_DATA(DEBUG, "(%d) %s\n", dev->vid, __func__); @@ -1646,28 +1647,32 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id, rte_spinlock_lock(&vq->access_lock); + n_inflight = vq->async_pkts_inflight_n; pkts_idx = vq->async_pkts_idx; async_pending_info = vq->async_pending_info; vq_size = vq->size; start_idx = virtio_dev_rx_async_get_info_idx(pkts_idx, vq_size, vq->async_pkts_inflight_n); - n_pkts_cpl = - vq->async_ops.check_completed_copies(vid, queue_id, 0, count); + n_pkts_cpl = vq->async_ops.check_completed_copies(vid, queue_id, + 0, ASYNC_MAX_POLL_SEG - vq->async_last_seg_n) + + vq->async_last_seg_n; rte_smp_wmb(); - while (likely(((start_idx + n_pkts_put) & (vq_size - 1)) != pkts_idx)) { + while (likely((n_pkts_put < count) && n_inflight)) { uint64_t info = async_pending_info[ (start_idx + n_pkts_put) & (vq_size - 1)]; uint64_t n_segs; n_pkts_put++; + n_inflight--; n_descs += info & ASYNC_PENDING_INFO_N_MSK; n_segs = info >> ASYNC_PENDING_INFO_N_SFT; if (n_segs) { - if (!n_pkts_cpl || n_pkts_cpl < n_segs) { + if (unlikely(n_pkts_cpl < n_segs)) { n_pkts_put--; + n_inflight++; n_descs -= info & ASYNC_PENDING_INFO_N_MSK; if (n_pkts_cpl) { async_pending_info[ @@ -1684,8 +1689,10 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id, } } + vq->async_last_seg_n = n_pkts_cpl; + if (n_pkts_put) { - vq->async_pkts_inflight_n -= n_pkts_put; + vq->async_pkts_inflight_n = n_inflight; __atomic_add_fetch(&vq->used->idx, n_descs, __ATOMIC_RELEASE); vhost_vring_call_split(dev, vq); -- 2.18.4
> -----Original Message-----
> From: Fu, Patrick <patrick.fu@intel.com>
> Sent: Wednesday, July 15, 2020 7:15 PM
> To: dev@dpdk.org; maxime.coquelin@redhat.com; Xia, Chenbo
> <chenbo.xia@intel.com>
> Cc: Fu, Patrick <patrick.fu@intel.com>; Wang, Yinan <yinan.wang@intel.com>
> Subject: [PATCH v2] vhost: support async copy free segmentations
>
> From: Patrick Fu <patrick.fu@intel.com>
>
> Vhost async enqueue assumes that all async copies should break at packet
> boundary. i.e. if a packet is splited into multiple copy segments, the async engine
> should always report copy completion when entire packet is finished. This patch
> removes the assumption.
>
> Fixes: cd6760da1076 ("vhost: introduce async enqueue for split ring")
>
> Signed-off-by: Patrick Fu <patrick.fu@intel.com>
> ---
> v2:
> - fix an issue that can stuck async poll when packets buffer is full
> - rename a local variable to better reflect its usage
>
> lib/librte_vhost/vhost.h | 3 +++
> lib/librte_vhost/virtio_net.c | 17 ++++++++++++-----
> 2 files changed, 15 insertions(+), 5 deletions(-)
>
> diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h index
> 8c01cee42..0f7212f88 100644
> --- a/lib/librte_vhost/vhost.h
> +++ b/lib/librte_vhost/vhost.h
> @@ -46,6 +46,8 @@
>
> #define MAX_PKT_BURST 32
>
> +#define ASYNC_MAX_POLL_SEG 255
> +
> #define VHOST_MAX_ASYNC_IT (MAX_PKT_BURST * 2) #define
> VHOST_MAX_ASYNC_VEC (BUF_VECTOR_MAX * 2)
>
> @@ -225,6 +227,7 @@ struct vhost_virtqueue {
> uint64_t *async_pending_info;
> uint16_t async_pkts_idx;
> uint16_t async_pkts_inflight_n;
> + uint16_t async_last_seg_n;
>
> /* vq async features */
> bool async_inorder;
> diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c index
> 1d0be3dd4..17808ab29 100644
> --- a/lib/librte_vhost/virtio_net.c
> +++ b/lib/librte_vhost/virtio_net.c
> @@ -1633,6 +1633,7 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid,
> uint16_t queue_id,
> struct vhost_virtqueue *vq;
> uint16_t n_pkts_cpl, n_pkts_put = 0, n_descs = 0;
> uint16_t start_idx, pkts_idx, vq_size;
> + uint16_t n_inflight;
> uint64_t *async_pending_info;
>
> VHOST_LOG_DATA(DEBUG, "(%d) %s\n", dev->vid, __func__); @@ -
> 1646,28 +1647,32 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid,
> uint16_t queue_id,
>
> rte_spinlock_lock(&vq->access_lock);
>
> + n_inflight = vq->async_pkts_inflight_n;
> pkts_idx = vq->async_pkts_idx;
> async_pending_info = vq->async_pending_info;
> vq_size = vq->size;
> start_idx = virtio_dev_rx_async_get_info_idx(pkts_idx,
> vq_size, vq->async_pkts_inflight_n);
>
> - n_pkts_cpl =
> - vq->async_ops.check_completed_copies(vid, queue_id, 0,
> count);
> + n_pkts_cpl = vq->async_ops.check_completed_copies(vid, queue_id,
> + 0, ASYNC_MAX_POLL_SEG - vq->async_last_seg_n) +
> + vq->async_last_seg_n;
>
> rte_smp_wmb();
>
> - while (likely(((start_idx + n_pkts_put) & (vq_size - 1)) != pkts_idx)) {
> + while (likely((n_pkts_put < count) && n_inflight)) {
> uint64_t info = async_pending_info[
> (start_idx + n_pkts_put) & (vq_size - 1)];
> uint64_t n_segs;
> n_pkts_put++;
> + n_inflight--;
> n_descs += info & ASYNC_PENDING_INFO_N_MSK;
> n_segs = info >> ASYNC_PENDING_INFO_N_SFT;
>
> if (n_segs) {
> - if (!n_pkts_cpl || n_pkts_cpl < n_segs) {
> + if (unlikely(n_pkts_cpl < n_segs)) {
> n_pkts_put--;
> + n_inflight++;
> n_descs -= info &
> ASYNC_PENDING_INFO_N_MSK;
> if (n_pkts_cpl) {
> async_pending_info[
> @@ -1684,8 +1689,10 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid,
> uint16_t queue_id,
> }
> }
>
> + vq->async_last_seg_n = n_pkts_cpl;
> +
> if (n_pkts_put) {
> - vq->async_pkts_inflight_n -= n_pkts_put;
> + vq->async_pkts_inflight_n = n_inflight;
> __atomic_add_fetch(&vq->used->idx, n_descs,
> __ATOMIC_RELEASE);
>
> vhost_vring_call_split(dev, vq);
> --
> 2.18.4
Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>
On 7/17/2020 4:21 AM, Xia, Chenbo wrote:
>
>> -----Original Message-----
>> From: Fu, Patrick <patrick.fu@intel.com>
>> Sent: Wednesday, July 15, 2020 7:15 PM
>> To: dev@dpdk.org; maxime.coquelin@redhat.com; Xia, Chenbo
>> <chenbo.xia@intel.com>
>> Cc: Fu, Patrick <patrick.fu@intel.com>; Wang, Yinan <yinan.wang@intel.com>
>> Subject: [PATCH v2] vhost: support async copy free segmentations
>>
>> From: Patrick Fu <patrick.fu@intel.com>
>>
>> Vhost async enqueue assumes that all async copies should break at packet
>> boundary. i.e. if a packet is splited into multiple copy segments, the async engine
>> should always report copy completion when entire packet is finished. This patch
>> removes the assumption.
>>
>> Fixes: cd6760da1076 ("vhost: introduce async enqueue for split ring")
>>
>> Signed-off-by: Patrick Fu <patrick.fu@intel.com>
>
> Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>
>
Applied to dpdk-next-net/master, thanks.
Hi Patrick, On 7/15/20 1:15 PM, patrick.fu@intel.com wrote: > From: Patrick Fu <patrick.fu@intel.com> > > Vhost async enqueue assumes that all async copies should break at packet > boundary. i.e. if a packet is splited into multiple copy segments, the > async engine should always report copy completion when entire packet is > finished. This patch removes the assumption. Could you please rework the commit message and title? It is hard to understand what the patch is doing and why. Thanks in advance, Maxime > Fixes: cd6760da1076 ("vhost: introduce async enqueue for split ring") > > Signed-off-by: Patrick Fu <patrick.fu@intel.com> > --- > v2: > - fix an issue that can stuck async poll when packets buffer is full > - rename a local variable to better reflect its usage > > lib/librte_vhost/vhost.h | 3 +++ > lib/librte_vhost/virtio_net.c | 17 ++++++++++++----- > 2 files changed, 15 insertions(+), 5 deletions(-) > > diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h > index 8c01cee42..0f7212f88 100644 > --- a/lib/librte_vhost/vhost.h > +++ b/lib/librte_vhost/vhost.h > @@ -46,6 +46,8 @@ > > #define MAX_PKT_BURST 32 > > +#define ASYNC_MAX_POLL_SEG 255 > + > #define VHOST_MAX_ASYNC_IT (MAX_PKT_BURST * 2) > #define VHOST_MAX_ASYNC_VEC (BUF_VECTOR_MAX * 2) > > @@ -225,6 +227,7 @@ struct vhost_virtqueue { > uint64_t *async_pending_info; > uint16_t async_pkts_idx; > uint16_t async_pkts_inflight_n; > + uint16_t async_last_seg_n; > > /* vq async features */ > bool async_inorder; > diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c > index 1d0be3dd4..17808ab29 100644 > --- a/lib/librte_vhost/virtio_net.c > +++ b/lib/librte_vhost/virtio_net.c > @@ -1633,6 +1633,7 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id, > struct vhost_virtqueue *vq; > uint16_t n_pkts_cpl, n_pkts_put = 0, n_descs = 0; > uint16_t start_idx, pkts_idx, vq_size; > + uint16_t n_inflight; > uint64_t *async_pending_info; > > VHOST_LOG_DATA(DEBUG, "(%d) %s\n", dev->vid, __func__); > @@ -1646,28 +1647,32 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id, > > rte_spinlock_lock(&vq->access_lock); > > + n_inflight = vq->async_pkts_inflight_n; > pkts_idx = vq->async_pkts_idx; > async_pending_info = vq->async_pending_info; > vq_size = vq->size; > start_idx = virtio_dev_rx_async_get_info_idx(pkts_idx, > vq_size, vq->async_pkts_inflight_n); > > - n_pkts_cpl = > - vq->async_ops.check_completed_copies(vid, queue_id, 0, count); > + n_pkts_cpl = vq->async_ops.check_completed_copies(vid, queue_id, > + 0, ASYNC_MAX_POLL_SEG - vq->async_last_seg_n) + > + vq->async_last_seg_n; > > rte_smp_wmb(); > > - while (likely(((start_idx + n_pkts_put) & (vq_size - 1)) != pkts_idx)) { > + while (likely((n_pkts_put < count) && n_inflight)) { > uint64_t info = async_pending_info[ > (start_idx + n_pkts_put) & (vq_size - 1)]; > uint64_t n_segs; > n_pkts_put++; > + n_inflight--; > n_descs += info & ASYNC_PENDING_INFO_N_MSK; > n_segs = info >> ASYNC_PENDING_INFO_N_SFT; > > if (n_segs) { > - if (!n_pkts_cpl || n_pkts_cpl < n_segs) { > + if (unlikely(n_pkts_cpl < n_segs)) { > n_pkts_put--; > + n_inflight++; > n_descs -= info & ASYNC_PENDING_INFO_N_MSK; > if (n_pkts_cpl) { > async_pending_info[ > @@ -1684,8 +1689,10 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id, > } > } > > + vq->async_last_seg_n = n_pkts_cpl; > + > if (n_pkts_put) { > - vq->async_pkts_inflight_n -= n_pkts_put; > + vq->async_pkts_inflight_n = n_inflight; > __atomic_add_fetch(&vq->used->idx, n_descs, __ATOMIC_RELEASE); > > vhost_vring_call_split(dev, vq); >
On 7/20/2020 3:58 PM, Maxime Coquelin wrote: > Hi Patrick, > > On 7/15/20 1:15 PM, patrick.fu@intel.com wrote: >> From: Patrick Fu <patrick.fu@intel.com> >> >> Vhost async enqueue assumes that all async copies should break at packet >> boundary. i.e. if a packet is splited into multiple copy segments, the >> async engine should always report copy completion when entire packet is >> finished. This patch removes the assumption. > > Could you please rework the commit message and title? > It is hard to understand what the patch is doing and why. Existing commit dropped from next-net and patchwork status updated. > > Thanks in advance, > Maxime > >> Fixes: cd6760da1076 ("vhost: introduce async enqueue for split ring") >> >> Signed-off-by: Patrick Fu <patrick.fu@intel.com> <...>
From: Patrick Fu <patrick.fu@intel.com> In async enqueue copy, a packet could be split into multiple copy segments. When polling the copy completion status, current async data path assumes the async device callbacks are aware of the packet boundary and return completed segments only if all segments belonging to the same packet are done. Such assumption are not generic to common async devices and may degrees the copy performance if async callbacks have to implement it in software manner. This patch adds tracking of the completed copy segments at vhost side. If async copy device reports partial completion of a packets, only vhost internal record is updated and vring status keeps unchanged until remaining segments of the packet are also finished. The async copy device is no longer necessary to care about the packet boundary. Fixes: cd6760da1076 ("vhost: introduce async enqueue for split ring") Signed-off-by: Patrick Fu <patrick.fu@intel.com> --- v2: - fix an issue that can stuck async poll when packets buffer is full v3: - revise commit message and title - rename a local variable to better reflect its usage lib/librte_vhost/vhost.h | 3 +++ lib/librte_vhost/virtio_net.c | 27 +++++++++++++++++---------- 2 files changed, 20 insertions(+), 10 deletions(-) diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h index 8c01cee42..0f7212f88 100644 --- a/lib/librte_vhost/vhost.h +++ b/lib/librte_vhost/vhost.h @@ -46,6 +46,8 @@ #define MAX_PKT_BURST 32 +#define ASYNC_MAX_POLL_SEG 255 + #define VHOST_MAX_ASYNC_IT (MAX_PKT_BURST * 2) #define VHOST_MAX_ASYNC_VEC (BUF_VECTOR_MAX * 2) @@ -225,6 +227,7 @@ struct vhost_virtqueue { uint64_t *async_pending_info; uint16_t async_pkts_idx; uint16_t async_pkts_inflight_n; + uint16_t async_last_seg_n; /* vq async features */ bool async_inorder; diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c index 1d0be3dd4..635113cb0 100644 --- a/lib/librte_vhost/virtio_net.c +++ b/lib/librte_vhost/virtio_net.c @@ -1631,8 +1631,9 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id, { struct virtio_net *dev = get_device(vid); struct vhost_virtqueue *vq; - uint16_t n_pkts_cpl, n_pkts_put = 0, n_descs = 0; + uint16_t n_segs_cpl, n_pkts_put = 0, n_descs = 0; uint16_t start_idx, pkts_idx, vq_size; + uint16_t n_inflight; uint64_t *async_pending_info; VHOST_LOG_DATA(DEBUG, "(%d) %s\n", dev->vid, __func__); @@ -1646,46 +1647,52 @@ uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id, rte_spinlock_lock(&vq->access_lock); + n_inflight = vq->async_pkts_inflight_n; pkts_idx = vq->async_pkts_idx; async_pending_info = vq->async_pending_info; vq_size = vq->size; start_idx = virtio_dev_rx_async_get_info_idx(pkts_idx, vq_size, vq->async_pkts_inflight_n); - n_pkts_cpl = - vq->async_ops.check_completed_copies(vid, queue_id, 0, count); + n_segs_cpl = vq->async_ops.check_completed_copies(vid, queue_id, + 0, ASYNC_MAX_POLL_SEG - vq->async_last_seg_n) + + vq->async_last_seg_n; rte_smp_wmb(); - while (likely(((start_idx + n_pkts_put) & (vq_size - 1)) != pkts_idx)) { + while (likely((n_pkts_put < count) && n_inflight)) { uint64_t info = async_pending_info[ (start_idx + n_pkts_put) & (vq_size - 1)]; uint64_t n_segs; n_pkts_put++; + n_inflight--; n_descs += info & ASYNC_PENDING_INFO_N_MSK; n_segs = info >> ASYNC_PENDING_INFO_N_SFT; if (n_segs) { - if (!n_pkts_cpl || n_pkts_cpl < n_segs) { + if (unlikely(n_segs_cpl < n_segs)) { n_pkts_put--; + n_inflight++; n_descs -= info & ASYNC_PENDING_INFO_N_MSK; - if (n_pkts_cpl) { + if (n_segs_cpl) { async_pending_info[ (start_idx + n_pkts_put) & (vq_size - 1)] = - ((n_segs - n_pkts_cpl) << + ((n_segs - n_segs_cpl) << ASYNC_PENDING_INFO_N_SFT) | (info & ASYNC_PENDING_INFO_N_MSK); - n_pkts_cpl = 0; + n_segs_cpl = 0; } break; } - n_pkts_cpl -= n_segs; + n_segs_cpl -= n_segs; } } + vq->async_last_seg_n = n_segs_cpl; + if (n_pkts_put) { - vq->async_pkts_inflight_n -= n_pkts_put; + vq->async_pkts_inflight_n = n_inflight; __atomic_add_fetch(&vq->used->idx, n_descs, __ATOMIC_RELEASE); vhost_vring_call_split(dev, vq); -- 2.18.4
Hi Maxime,
> -----Original Message-----
> From: Maxime Coquelin <maxime.coquelin@redhat.com>
> Sent: Monday, July 20, 2020 10:58 PM
> To: Fu, Patrick <patrick.fu@intel.com>; dev@dpdk.org; Xia, Chenbo
> <chenbo.xia@intel.com>
> Cc: Wang, Yinan <yinan.wang@intel.com>
> Subject: Re: [PATCH v2] vhost: support async copy free segmentations
>
> Hi Patrick,
>
> On 7/15/20 1:15 PM, patrick.fu@intel.com wrote:
> > From: Patrick Fu <patrick.fu@intel.com>
> >
> > Vhost async enqueue assumes that all async copies should break at
> > packet boundary. i.e. if a packet is splited into multiple copy
> > segments, the async engine should always report copy completion when
> > entire packet is finished. This patch removes the assumption.
>
> Could you please rework the commit message and title?
> It is hard to understand what the patch is doing and why.
I revise the commit message and title in my v3 patch. Hope that one will be more clear.
Thanks,
Patrick
On 7/21/20 7:47 AM, patrick.fu@intel.com wrote: > From: Patrick Fu <patrick.fu@intel.com> > > In async enqueue copy, a packet could be split into multiple copy > segments. When polling the copy completion status, current async data > path assumes the async device callbacks are aware of the packet > boundary and return completed segments only if all segments belonging > to the same packet are done. Such assumption are not generic to common > async devices and may degrees the copy performance if async callbacks s/degrees/degrades/ > have to implement it in software manner. > > This patch adds tracking of the completed copy segments at vhost side. > If async copy device reports partial completion of a packets, only > vhost internal record is updated and vring status keeps unchanged > until remaining segments of the packet are also finished. The async > copy device is no longer necessary to care about the packet boundary. > > Fixes: cd6760da1076 ("vhost: introduce async enqueue for split ring") > > Signed-off-by: Patrick Fu <patrick.fu@intel.com> > --- > v2: > - fix an issue that can stuck async poll when packets buffer is full > v3: > - revise commit message and title > - rename a local variable to better reflect its usage > > lib/librte_vhost/vhost.h | 3 +++ > lib/librte_vhost/virtio_net.c | 27 +++++++++++++++++---------- > 2 files changed, 20 insertions(+), 10 deletions(-) With above typo fixed (can be done when applying, no need to resend): Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com> Thanks, Maxime
On 7/21/2020 9:40 AM, Maxime Coquelin wrote:
>
>
> On 7/21/20 7:47 AM, patrick.fu@intel.com wrote:
>> From: Patrick Fu <patrick.fu@intel.com>
>>
>> In async enqueue copy, a packet could be split into multiple copy
>> segments. When polling the copy completion status, current async data
>> path assumes the async device callbacks are aware of the packet
>> boundary and return completed segments only if all segments belonging
>> to the same packet are done. Such assumption are not generic to common
>> async devices and may degrees the copy performance if async callbacks
>
> s/degrees/degrades/
>
>> have to implement it in software manner.
>>
>> This patch adds tracking of the completed copy segments at vhost side.
>> If async copy device reports partial completion of a packets, only
>> vhost internal record is updated and vring status keeps unchanged
>> until remaining segments of the packet are also finished. The async
>> copy device is no longer necessary to care about the packet boundary.
>>
>> Fixes: cd6760da1076 ("vhost: introduce async enqueue for split ring")
>>
>> Signed-off-by: Patrick Fu <patrick.fu@intel.com>
>
> With above typo fixed (can be done when applying, no need to resend):
> Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
>
Applied to dpdk-next-net/master, thanks.