d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Make the feature negotiation code easier to follow

Browse Source 
MFC after:	1 week
This commit is contained in:
bryanv 2014-06-16 04:29:28 +00:00
parent e5f8bdea96
commit ae22af0ab4
1 changed files with 23 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

45
sys/dev/virtio/network/if_vtnet.c
View File

@ -552,37 +552,38 @@ vtnet_negotiate_features(struct vtnet_softc *sc)
mask |= VTNET_TSO_FEATURES;
if (vtnet_tunable_int(sc, "lro_disable", vtnet_lro_disable))
mask |= VTNET_LRO_FEATURES;
#ifndef VTNET_LEGACY_TX
if (vtnet_tunable_int(sc, "mq_disable", vtnet_mq_disable))
mask |= VIRTIO_NET_F_MQ;
#ifdef VTNET_LEGACY_TX
#else
mask |= VIRTIO_NET_F_MQ;
#endif
features = VTNET_FEATURES & ~mask;
sc->vtnet_features = virtio_negotiate_features(dev, features);
if (virtio_with_feature(dev, VTNET_LRO_FEATURES) == 0)
return;
if (virtio_with_feature(dev, VIRTIO_NET_F_MRG_RXBUF))
return;
if (virtio_with_feature(dev, VTNET_LRO_FEATURES) &&
virtio_with_feature(dev, VIRTIO_NET_F_MRG_RXBUF) == 0) {
/*
* LRO without mergeable buffers requires special care. This
* is not ideal because every receive buffer must be large
* enough to hold the maximum TCP packet, the Ethernet header,
* and the header. This requires up to 34 descriptors with
* MCLBYTES clusters. If we do not have indirect descriptors,
* LRO is disabled since the virtqueue will not contain very
* many receive buffers.
*/
if (!virtio_with_feature(dev, VIRTIO_RING_F_INDIRECT_DESC)) {
device_printf(dev,
"LRO disabled due to both mergeable buffers and "
"indirect descriptors not negotiated\n");
/*
* LRO without mergeable buffers requires special care. This is not
* ideal because every receive buffer must be large enough to hold
* the maximum TCP packet, the Ethernet header, and the header. This
* requires up to 34 descriptors with MCLBYTES clusters. If we do
* not have indirect descriptors, LRO is disabled since the virtqueue
* will not contain very many receive buffers.
*/
if (virtio_with_feature(dev, VIRTIO_RING_F_INDIRECT_DESC) == 0) {
device_printf(dev,
"LRO disabled due to both mergeable buffers and indirect "
"descriptors not negotiated\n");
features &= ~VTNET_LRO_FEATURES;
sc->vtnet_features = virtio_negotiate_features(dev, features);
} else
sc->vtnet_flags |= VTNET_FLAG_LRO_NOMRG;
features &= ~VTNET_LRO_FEATURES;
sc->vtnet_features =
virtio_negotiate_features(dev, features);
} else
sc->vtnet_flags |= VTNET_FLAG_LRO_NOMRG;
}
}
static void