[dpdk-dev] [PATCH v4 7/7] virtio: pick simple rx/tx func

[Xie, Huawei]

On 10/23/2015 12:59 AM, Stephen Hemminger wrote:
> On Thu, 22 Oct 2015 20:09:51 +0800
> Huawei Xie <huawei.xie at intel.com> wrote:
>
>> +	/* Use simple rx/tx func if single segment and no offloads */
>> +	if ((tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) == VIRTIO_SIMPLE_FLAGS &&
>> +	     !vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF))
> Since with QEMU/KVM the code will negotiate to use MRG_RXBUF, this
> code path will not get used in common case anyway.
>
Yes, the common configuration is merge-able enabled.
We need to add mrg_rxbuf=off(in qemu command line), or disable
merge-able feature(in switch application) through vhost API for
non-mergable.