virtio-net: initial rx sysfs support, export mergeable rx buffer size

Add initial support for per-rx queue sysfs attributes to virtio-net. If
mergeable packet buffers are enabled, adds a read-only mergeable packet
buffer size sysfs attribute for each RX queue.

Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael Dalton <mwdalton@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Michael Dalton 2014-01-16 22:23:30 -08:00 committed by David S. Miller
parent 03144b5869
commit fbf28d78f5

View File

@ -600,18 +600,25 @@ static int add_recvbuf_big(struct receive_queue *rq, gfp_t gfp)
return err;
}
static int add_recvbuf_mergeable(struct receive_queue *rq, gfp_t gfp)
static unsigned int get_mergeable_buf_len(struct ewma *avg_pkt_len)
{
const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
unsigned int len;
len = hdr_len + clamp_t(unsigned int, ewma_read(avg_pkt_len),
GOOD_PACKET_LEN, PAGE_SIZE - hdr_len);
return ALIGN(len, MERGEABLE_BUFFER_ALIGN);
}
static int add_recvbuf_mergeable(struct receive_queue *rq, gfp_t gfp)
{
struct page_frag *alloc_frag = &rq->alloc_frag;
char *buf;
unsigned long ctx;
int err;
unsigned int len, hole;
len = hdr_len + clamp_t(unsigned int, ewma_read(&rq->mrg_avg_pkt_len),
GOOD_PACKET_LEN, PAGE_SIZE - hdr_len);
len = ALIGN(len, MERGEABLE_BUFFER_ALIGN);
len = get_mergeable_buf_len(&rq->mrg_avg_pkt_len);
if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
return -ENOMEM;
@ -1584,6 +1591,33 @@ static int init_vqs(struct virtnet_info *vi)
return ret;
}
#ifdef CONFIG_SYSFS
static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
struct rx_queue_attribute *attribute, char *buf)
{
struct virtnet_info *vi = netdev_priv(queue->dev);
unsigned int queue_index = get_netdev_rx_queue_index(queue);
struct ewma *avg;
BUG_ON(queue_index >= vi->max_queue_pairs);
avg = &vi->rq[queue_index].mrg_avg_pkt_len;
return sprintf(buf, "%u\n", get_mergeable_buf_len(avg));
}
static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
__ATTR_RO(mergeable_rx_buffer_size);
static struct attribute *virtio_net_mrg_rx_attrs[] = {
&mergeable_rx_buffer_size_attribute.attr,
NULL
};
static const struct attribute_group virtio_net_mrg_rx_group = {
.name = "virtio_net",
.attrs = virtio_net_mrg_rx_attrs
};
#endif
static int virtnet_probe(struct virtio_device *vdev)
{
int i, err;
@ -1698,6 +1732,10 @@ static int virtnet_probe(struct virtio_device *vdev)
if (err)
goto free_stats;
#ifdef CONFIG_SYSFS
if (vi->mergeable_rx_bufs)
dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
#endif
netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);