Hi,
> -----Original Message-----
> From: Maxime Coquelin <maxime.coque...@redhat.com>
> Sent: Wednesday, February 3, 2021 5:52 PM
> To: Jiang, Cheng1 <cheng1.ji...@intel.com>; Xia, Chenbo
> <chenbo....@intel.com>
> Cc: dev@dpdk.org; Hu, Jiayu <jiayu...@intel.com>; Yang, YvonneX
> <yvonnex.y...@intel.com>; Wang, Yinan <yinan.w...@intel.com>
> Subject: Re: [PATCH v3] examples/vhost: remove async inflight packet
> counter
>
>
>
> On 2/2/21 7:17 AM, Cheng Jiang wrote:
> > Remove async inflight packet counter since there is no need to keep
> > tracking it. Increase MAX_ENQUEUED_SIZE to prevent packet segment
> > number tracking ring from being exhausted.
>
> Is that an optimization or a fix?
>
> If the former, let's move it to v21.05.
>
I think it's a fix since there is no need to keep the inflight packet counter,
sorry I forget adding the fixes, I can submit a v4 to fix it.
> >
> > Fixes: a68ba8e0a6b6 ("examples/vhost: refactor vhost data path")
> >
> > Signed-off-by: Cheng Jiang <cheng1.ji...@intel.com>
> > ---
> > v3: fixed fixes commit id in git log
> >
> > v2: fixed a typo
> >
> > examples/vhost/ioat.h | 2 +-
> > examples/vhost/main.c | 10 +--------- examples/vhost/main.h | 1 -
> > 3 files changed, 2 insertions(+), 11 deletions(-)
> >
> > diff --git a/examples/vhost/ioat.h b/examples/vhost/ioat.h index
> > 0a1dbb811..1aa28ed6a 100644
> > --- a/examples/vhost/ioat.h
> > +++ b/examples/vhost/ioat.h
> > @@ -11,7 +11,7 @@
> >
> > #define MAX_VHOST_DEVICE 1024
> > #define IOAT_RING_SIZE 4096
> > -#define MAX_ENQUEUED_SIZE 512
> > +#define MAX_ENQUEUED_SIZE 4096
>
> Basically, this the size of the ring size, correct?
> It might be further simplified then.
>
Yes, it's a the size of packet tracking ring, and it should be no less then
IOAT_RING_SIZE for some corner cases.
I'm not sure I understand what you mean by saying It might be further
simplified then.
Thanks,
Cheng
> >
> > struct dma_info {
> > struct rte_pci_addr addr;
> > diff --git a/examples/vhost/main.c b/examples/vhost/main.c index
> > e74fc8750..ca73e7086 100644
> > --- a/examples/vhost/main.c
> > +++ b/examples/vhost/main.c
> > @@ -831,11 +831,8 @@ complete_async_pkts(struct vhost_dev *vdev)
> >
> > complete_count = rte_vhost_poll_enqueue_completed(vdev->vid,
> > VIRTIO_RXQ, p_cpl,
> MAX_PKT_BURST);
> > - if (complete_count) {
> > - __atomic_sub_fetch(&vdev->nr_async_pkts,
> complete_count,
> > - __ATOMIC_SEQ_CST);
> > + if (complete_count)
> > free_pkts(p_cpl, complete_count);
> > - }
> > }
> >
> > static __rte_always_inline void
> > @@ -878,8 +875,6 @@ drain_vhost(struct vhost_dev *vdev)
> > complete_async_pkts(vdev);
> > ret = rte_vhost_submit_enqueue_burst(vdev->vid,
> VIRTIO_RXQ,
> > m, nr_xmit, m_cpu_cpl,
> &cpu_cpl_nr);
> > - __atomic_add_fetch(&vdev->nr_async_pkts, ret -
> cpu_cpl_nr,
> > - __ATOMIC_SEQ_CST);
> >
> > if (cpu_cpl_nr)
> > free_pkts(m_cpu_cpl, cpu_cpl_nr);
> > @@ -1210,9 +1205,6 @@ drain_eth_rx(struct vhost_dev *vdev)
> > enqueue_count = rte_vhost_submit_enqueue_burst(vdev-
> >vid,
> > VIRTIO_RXQ, pkts, rx_count,
> > m_cpu_cpl, &cpu_cpl_nr);
> > - __atomic_add_fetch(&vdev->nr_async_pkts,
> > - enqueue_count - cpu_cpl_nr,
> > - __ATOMIC_SEQ_CST);
> > if (cpu_cpl_nr)
> > free_pkts(m_cpu_cpl, cpu_cpl_nr);
> >
> > diff --git a/examples/vhost/main.h b/examples/vhost/main.h index
> > 2d6c05fd7..0ccdce4b4 100644
> > --- a/examples/vhost/main.h
> > +++ b/examples/vhost/main.h
> > @@ -51,7 +51,6 @@ struct vhost_dev {
> > uint64_t features;
> > size_t hdr_len;
> > uint16_t nr_vrings;
> > - uint64_t nr_async_pkts;
> > struct rte_vhost_memory *mem;
> > struct device_statistics stats;
> > TAILQ_ENTRY(vhost_dev) global_vdev_entry;
> > --
> > 2.29.2
> >
