Hi,
> -----Original Message-----
> From: Maxime Coquelin <maxime.coque...@redhat.com>
> Sent: Thursday, January 21, 2021 8:35 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 v9 1/2] examples/vhost: add ioat ring space count and
> check
>
>
>
> On 1/12/21 5:38 AM, Cheng Jiang wrote:
> > Add ioat ring space count and check, if ioat ring space is not enough
> > for the next async vhost packet enqueue, then just return to prevent
> > enqueue failure. Add rte_ioat_completed_ops() fail handler.
> >
> > Signed-off-by: Cheng Jiang <cheng1.ji...@intel.com>
> > Reviewed-by: Jiayu Hu <jiayu...@intel.com>
> > Reviewed-by: Maxime Coquelin <maxime.coque...@redhat.com>
> > ---
> > examples/vhost/ioat.c | 24 +++++++++++++-----------
> > 1 file changed, 13 insertions(+), 11 deletions(-)
> >
> > diff --git a/examples/vhost/ioat.c b/examples/vhost/ioat.c index
> > 71d8a1f1f..dbad28d43 100644
> > --- a/examples/vhost/ioat.c
> > +++ b/examples/vhost/ioat.c
> > @@ -17,6 +17,7 @@ struct packet_tracker {
> > unsigned short next_read;
> > unsigned short next_write;
> > unsigned short last_remain;
> > + unsigned short ioat_space;
> > };
> >
> > struct packet_tracker cb_tracker[MAX_VHOST_DEVICE]; @@ -113,7 +114,7
> > @@ open_ioat(const char *value)
> > goto out;
> > }
> > rte_rawdev_start(dev_id);
> > -
> > + cb_tracker[dev_id].ioat_space = IOAT_RING_SIZE;
> > dma_info->nr++;
> > i++;
> > }
> > @@ -140,13 +141,9 @@ ioat_transfer_data_cb(int vid, uint16_t queue_id,
> > src = descs[i_desc].src;
> > dst = descs[i_desc].dst;
> > i_seg = 0;
> > + if (cb_tracker[dev_id].ioat_space < src->nr_segs)
> > + break;
> > while (i_seg < src->nr_segs) {
> > - /*
> > - * TODO: Assuming that the ring space of the
> > - * IOAT device is large enough, so there is no
> > - * error here, and the actual error handling
> > - * will be added later.
> > - */
> > rte_ioat_enqueue_copy(dev_id,
> > (uintptr_t)(src->iov[i_seg].iov_base)
> > + src->offset,
> > @@ -158,7 +155,8 @@ ioat_transfer_data_cb(int vid, uint16_t queue_id,
> > i_seg++;
> > }
> > write &= mask;
> > - cb_tracker[dev_id].size_track[write] = i_seg;
> > + cb_tracker[dev_id].size_track[write] = src->nr_segs;
> > + cb_tracker[dev_id].ioat_space -= src->nr_segs;
> > write++;
> > }
> > } else {
> > @@ -178,17 +176,21 @@ ioat_check_completed_copies_cb(int vid,
> uint16_t
> > queue_id, {
> > if (!opaque_data) {
> > uintptr_t dump[255];
> > - unsigned short n_seg;
> > + int n_seg;
> > unsigned short read, write;
> > unsigned short nb_packet = 0;
> > unsigned short mask = MAX_ENQUEUED_SIZE - 1;
> > unsigned short i;
> > +
> > int dev_id = dma_bind[vid].dmas[queue_id * 2
> > + VIRTIO_RXQ].dev_id;
> > n_seg = rte_ioat_completed_ops(dev_id, 255, dump, dump);
> > - n_seg += cb_tracker[dev_id].last_remain;
> > - if (!n_seg)
> > + if (n_seg <= 0)
> > return 0;
>
> In a separate patch, it might make sense to propagate the error if
> rte_ioat_completed_ops return -1.
Sure, I'll send a patch to fix it when this patch set is merged.
Thanks,
Cheng
>
> Reviewed-by: Maxime Coquelin <maxime.coque...@redhat.com>
>
> Maxime
> > +
> > + cb_tracker[dev_id].ioat_space += n_seg;
> > + n_seg += cb_tracker[dev_id].last_remain;
> > +
> > read = cb_tracker[dev_id].next_read;
> > write = cb_tracker[dev_id].next_write;
> > for (i = 0; i < max_packets; i++) {
> > --
> > 2.29.2
> >
