On Thu, Nov 12, 2020 at 9:48 AM Maxime Coquelin
<maxime.coque...@redhat.com> wrote:
> On 11/11/20 4:40 PM, Marvin Liu wrote:
> > Data prefetch instruction can preload data into cpu’s hierarchical
> > cache before data access. Virtio datapath utilized this feature for
> > data access acceleration. As config RTE_PMD_PACKET_PREFETCH was
> > discarded, now packet data prefetch is enabled based on architecture.
> >
> > Signed-off-by: Marvin Liu <yong....@intel.com>
> >
> > diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
> > index 42c4c9882..0196290a5 100644
> > --- a/drivers/net/virtio/virtqueue.h
> > +++ b/drivers/net/virtio/virtqueue.h
> > @@ -106,7 +106,7 @@ virtqueue_store_flags_packed(struct vring_packed_desc
> > *dp,
> > dp->flags = flags;
> > }
> > }
> > -#ifdef RTE_PMD_PACKET_PREFETCH
> > +#if defined(RTE_ARCH_X86)
> > #define rte_packet_prefetch(p) rte_prefetch1(p)
> > #else
> > #define rte_packet_prefetch(p) do {} while(0)
> >
>
> Thanks for catching this issue.
> I agree it should be re-enabled by default, and not only on X86, not
> only on Virtio PMD.
>
> AFAICS, prefetch was enabled for all platforms before the switch to
> Meson, so I see it as an involuntary change that needs to be reverted.
Yes and this will also solve https://patchwork.dpdk.org/patch/83468/.
Thanks.
--
David Marchand
