On 10/15/19 8:59 PM, Flavio Leitner wrote:
> The rte_vhost_dequeue_burst supports two ways of dequeuing data.
> If the data fits into a buffer, then all data is copied and a
> single linear buffer is returned. Otherwise it allocates
> additional mbufs and chains them together to return a multiple
> segments mbuf.
>
> While that covers most use cases, it forces applications that
> need to work with larger data sizes to support multiple segments
> mbufs. The non-linear characteristic brings complexity and
> performance implications to the application.
>
> To resolve the issue, add support to attach external buffer
> to a pktmbuf and let the host provide during registration if
> attaching an external buffer to pktmbuf is supported and if
> only linear buffer are supported.
>
> Signed-off-by: Flavio Leitner <f...@sysclose.org>
> ---
> doc/guides/prog_guide/vhost_lib.rst | 35 +++++++++
> lib/librte_vhost/rte_vhost.h | 4 +
> lib/librte_vhost/socket.c | 22 ++++++
> lib/librte_vhost/vhost.c | 22 ++++++
> lib/librte_vhost/vhost.h | 4 +
> lib/librte_vhost/virtio_net.c | 109 ++++++++++++++++++++++++----
> 6 files changed, 182 insertions(+), 14 deletions(-)
>
> - Changelog:
> v5:
> - fixed to destroy mutex if incompatible flags
> v4:
> - allow to use pktmbuf if there is exact space
> - removed log message if the buffer is too big
> - fixed the length to include align padding
> - free allocated buf if shinfo fails
> v3:
> - prevent the new features to be used with zero copy
> - fixed sizeof() usage
> - fixed log msg indentation
> - removed/replaced asserts
> - used the correct virt2iova function
> - fixed the patch's title
> - OvS PoC code:
> https://github.com/fleitner/ovs/tree/rte_malloc-v3
> v2:
> - Used rte_malloc() instead of another mempool as suggested by Shahaf.
> - Added the documentation section.
> - Using driver registration to negotiate the features.
> - OvS PoC code:
>
> https://github.com/fleitner/ovs/commit/8fc197c40b1d4fda331686a7b919e9e2b670dda7
Applied to dpdk-next-virtio/master.
Thanks,
Maxime
