Hi Jiayu, > -----Original Message----- > From: Hu, Jiayu <jiayu...@intel.com> > Sent: Monday, May 16, 2022 1:53 PM > To: Ding, Xuan <xuan.d...@intel.com>; maxime.coque...@redhat.com; Xia, > Chenbo <chenbo....@intel.com> > Cc: dev@dpdk.org; Jiang, Cheng1 <cheng1.ji...@intel.com>; Pai G, Sunil > <sunil.pa...@intel.com>; lian...@liangbit.com; Wang, YuanX > <yuanx.w...@intel.com> > Subject: RE: [PATCH v7 4/5] vhost: support async dequeue for split ring > > Hi Xuan, > > > -----Original Message----- > > From: Ding, Xuan <xuan.d...@intel.com> > > Sent: Monday, May 16, 2022 10:43 AM > > To: maxime.coque...@redhat.com; Xia, Chenbo <chenbo....@intel.com> > > Cc: dev@dpdk.org; Hu, Jiayu <jiayu...@intel.com>; Jiang, Cheng1 > > <cheng1.ji...@intel.com>; Pai G, Sunil <sunil.pa...@intel.com>; > > lian...@liangbit.com; Ding, Xuan <xuan.d...@intel.com>; Wang, YuanX > > <yuanx.w...@intel.com> > > Subject: [PATCH v7 4/5] vhost: support async dequeue for split ring > > > > From: Xuan Ding <xuan.d...@intel.com> > > > > This patch implements asynchronous dequeue data path for vhost split > > ring, a new API rte_vhost_async_try_dequeue_burst() is introduced. > > > > Signed-off-by: Xuan Ding <xuan.d...@intel.com> > > Signed-off-by: Yuan Wang <yuanx.w...@intel.com> > > Tested-by: Yvonne Yang <yvonnex.y...@intel.com> > > Reviewed-by: Maxime Coquelin <maxime.coque...@redhat.com> > > --- > > doc/guides/prog_guide/vhost_lib.rst | 7 + > > doc/guides/rel_notes/release_22_07.rst | 5 + > > lib/vhost/rte_vhost_async.h | 37 +++ > > lib/vhost/version.map | 2 +- > > lib/vhost/virtio_net.c | 337 +++++++++++++++++++++++++ > > 5 files changed, 387 insertions(+), 1 deletion(-) > > > > diff --git a/doc/guides/prog_guide/vhost_lib.rst > > b/doc/guides/prog_guide/vhost_lib.rst > > index f287b76ebf..09c1c24b48 100644 > > --- a/doc/guides/prog_guide/vhost_lib.rst > > +++ b/doc/guides/prog_guide/vhost_lib.rst > > @@ -282,6 +282,13 @@ The following is an overview of some key Vhost > > API > > functions: > > Clear inflight packets which are submitted to DMA engine in vhost > > async data > > path. Completed packets are returned to applications through ``pkts``. > > > > +* ``rte_vhost_async_try_dequeue_burst(int vid, uint16_t queue_id, > > + struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t > > +count, int *nr_inflight, uint16_t dma_id, uint16_t vchan_id)`` > > In dmadev library, dma_id is int16_t, rather than uint16_t.
Thanks for the reminder. I will fix it in v8. > > > + > > + Receives (dequeues) ``count`` packets from guest to host in async > > + data path, and stored them at ``pkts``. > > + > > Vhost-user Implementations > > -------------------------- > > > > diff --git a/doc/guides/rel_notes/release_22_07.rst > > b/doc/guides/rel_notes/release_22_07.rst > > index 88b1e478d4..564d88623e 100644 > > --- a/doc/guides/rel_notes/release_22_07.rst > > +++ b/doc/guides/rel_notes/release_22_07.rst > > @@ -70,6 +70,11 @@ New Features > > Added an API which can get the number of inflight packets in > > vhost async data path without using lock. > > > > +* **Added vhost async dequeue API to receive pkts from guest.** > > + > > + Added vhost async dequeue API which can leverage DMA devices to > > + accelerate receiving pkts from guest. > > + > > Removed Items > > ------------- > > > > diff --git a/lib/vhost/rte_vhost_async.h b/lib/vhost/rte_vhost_async.h > > index > > 70234debf9..2789492e38 100644 > > --- a/lib/vhost/rte_vhost_async.h > > +++ b/lib/vhost/rte_vhost_async.h > > @@ -204,6 +204,43 @@ uint16_t > rte_vhost_clear_queue_thread_unsafe(int > > vid, uint16_t queue_id, __rte_experimental int > > rte_vhost_async_dma_configure(int16_t dma_id, uint16_t vchan_id); > > > > +/** > > + * @warning > > + * @b EXPERIMENTAL: this API may change, or be removed, without prior > > +notice > > + * > > + * This function tries to receive packets from the guest with > > +offloading > > + * copies to the async channel. The packets that are transfer > > +completed > > In rte_vhost_async.h, DMA vChannel is referred as async channel or async > copy engine. But I think it's better to replace all with DMA vChannel to be > consistent with DPDK. Thanks for your suggestion, I will refine the API description in next version. > > > + * are returned in "pkts". The other packets that their copies are > > +submitted to > > + * the async channel but not completed are called "in-flight packets". > > + * This function will not return in-flight packets until their copies > > +are > > + * completed by the async channel. > > + * > > + * @param vid > > + * ID of vhost device to dequeue data > > + * @param queue_id > > + * ID of virtqueue to dequeue data > > + * @param mbuf_pool > > + * Mbuf_pool where host mbuf is allocated > > + * @param pkts > > + * Blank array to keep successfully dequeued packets > > + * @param count > > + * Size of the packet array > > + * @param nr_inflight > > + * >= 0: The amount of in-flight packets > > Better to add more descriptions about the meaning of "nr_inflight". Same as above. Regards, Xuan > > Thanks, > Jiayu
