similar to: [PATCH RFC net-next] virtio_net: refill buffer right after being used

The following series applies to net-next. The following series changes the low memory paths in virtio_net to not disable NAPI while waiting in the allocator in the slow path. It attempts to rectify some performance problems we've seen where the network performance drops significantly when memory is low. The working theory is that the disabling of NAPI while allocations are occuring in the

The following series applies to net-next. The following series changes the low memory paths in virtio_net to not disable NAPI while waiting in the allocator in the slow path. It attempts to rectify some performance problems we've seen where the network performance drops significantly when memory is low. The working theory is that the disabling of NAPI while allocations are occuring in the

Too many places poke at [rs]q->vq->vdev->priv just to get the the vi structure. Let's just pass the pointer around: seems cleaner, and might even be faster. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 36 +++++++++++++++++++----------------- 1 file changed, 19 insertions(+), 17 deletions(-) diff --git a/drivers/net/virtio_net.c

Too many places poke at [rs]q->vq->vdev->priv just to get the the vi structure. Let's just pass the pointer around: seems cleaner, and might even be faster. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 36 +++++++++++++++++++----------------- 1 file changed, 19 insertions(+), 17 deletions(-) diff --git a/drivers/net/virtio_net.c

The following series applies to net-next. The following series changes the low memory paths in virtio_net to allow the driver to contribute to reclaim when memory is tight. It attempts to rectify some performance problems we've seen where the network performance drops significantly when memory is low. The working theory is that while the driver contributes to memory pressure when throughput

The following series applies to net-next. The following series changes the low memory paths in virtio_net to allow the driver to contribute to reclaim when memory is tight. It attempts to rectify some performance problems we've seen where the network performance drops significantly when memory is low. The working theory is that while the driver contributes to memory pressure when throughput

virtio 1.0 doesn't use virtio_net_hdr anymore, and in fact, it's not really useful since virtio_net_hdr_mrg_rxbuf includes that as the first field anyway. Let's drop it, precalculate header len and store within vi instead. This way we can also remove struct skb_vnet_hdr. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck at

virtio 1.0 doesn't use virtio_net_hdr anymore, and in fact, it's not really useful since virtio_net_hdr_mrg_rxbuf includes that as the first field anyway. Let's drop it, precalculate header len and store within vi instead. This way we can also remove struct skb_vnet_hdr. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck at

We currently fill all of RX ring, then add_buf returns ENOSPC, which gets mis-detected as an out of memory condition and causes us to reschedule the work, and so on forever. Fix this by oom = err == -ENOMEM; Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- Rusty, please review the following patch for 2.6.35. drivers/net/virtio_net.c | 7 +++---- 1 files changed, 3

We currently fill all of RX ring, then add_buf returns ENOSPC, which gets mis-detected as an out of memory condition and causes us to reschedule the work, and so on forever. Fix this by oom = err == -ENOMEM; Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- Rusty, please review the following patch for 2.6.35. drivers/net/virtio_net.c | 7 +++---- 1 files changed, 3

For small packets data copy was observed to take up about 15% CPU time. Switch to build_skb and avoid the copy when using mergeable rx buffers. As a bonus, medium-size skbs that fit in a page will be completely linear. Of course, we now need to lower the lower bound on packet size, to make sure a sane number of skbs fits in rx socket buffer. By how much? I don't know yet. It might also be

For small packets data copy was observed to take up about 15% CPU time. Switch to build_skb and avoid the copy when using mergeable rx buffers. As a bonus, medium-size skbs that fit in a page will be completely linear. Of course, we now need to lower the lower bound on packet size, to make sure a sane number of skbs fits in rx socket buffer. By how much? I don't know yet. It might also be

virtio 1.0 doesn't use virtio_net_hdr anymore, and in fact, it's not really useful since virtio_net_hdr_mrg_rxbuf includes that as the first field anyway. Let's drop it, precalculate header len and store within vi instead. This way we can also remove struct skb_vnet_hdr. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 88

virtio 1.0 doesn't use virtio_net_hdr anymore, and in fact, it's not really useful since virtio_net_hdr_mrg_rxbuf includes that as the first field anyway. Let's drop it, precalculate header len and store within vi instead. This way we can also remove struct skb_vnet_hdr. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 88

virtio 1.0 doesn't use virtio_net_hdr anymore, and in fact, it's not really useful since virtio_net_hdr_mrg_rxbuf includes that as the first field anyway. Let's drop it, precalculate header len and store within vi instead. This way we can also remove struct skb_vnet_hdr. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 90

virtio 1.0 doesn't use virtio_net_hdr anymore, and in fact, it's not really useful since virtio_net_hdr_mrg_rxbuf includes that as the first field anyway. Let's drop it, precalculate header len and store within vi instead. This way we can also remove struct skb_vnet_hdr. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 90

virtio 1.0 doesn't use virtio_net_hdr anymore, and in fact, it's not really useful since virtio_net_hdr_mrg_rxbuf includes that as the first field anyway. Let's drop it, precalculate header len and store within vi instead. This way we can also remove struct skb_vnet_hdr. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck at

virtio 1.0 doesn't use virtio_net_hdr anymore, and in fact, it's not really useful since virtio_net_hdr_mrg_rxbuf includes that as the first field anyway. Let's drop it, precalculate header len and store within vi instead. This way we can also remove struct skb_vnet_hdr. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck at

virtio 1.0 doesn't use virtio_net_hdr anymore, and in fact, it's not really useful since virtio_net_hdr_mrg_rxbuf includes that as the first field anyway. Let's drop it, precalculate header len and store within vi instead. This way we can also remove struct skb_vnet_hdr. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck at

virtio 1.0 doesn't use virtio_net_hdr anymore, and in fact, it's not really useful since virtio_net_hdr_mrg_rxbuf includes that as the first field anyway. Let's drop it, precalculate header len and store within vi instead. This way we can also remove struct skb_vnet_hdr. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck at