UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

hv_netvsc: Use the xmit_more skb flag to optimize signaling the host 

Based on the information given to this driver (via the xmit_more skb flag),
we can defer signaling the host if more packets are on the way. This will help
make the host more efficient since it can potentially process a larger batch of
packets. Implement this optimization.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
KY Srinivasan 2015-05-11 15:39:46 -07:00 committed by David S. Miller
parent 9eea922264
commit 82fa3c776e
1 changed files with 27 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

43
drivers/net/hyperv/netvsc.c
View File

@ -743,6 +743,7 @@ static inline int netvsc_send_pkt(
u64 req_id; u64 req_id;
int ret; int ret;
struct hv_page_buffer *pgbuf; struct hv_page_buffer *pgbuf;
u32 ring_avail = hv_ringbuf_avail_percent(&out_channel->outbound);
nvmsg.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT; nvmsg.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
if (packet->is_data_pkt) { if (packet->is_data_pkt) {
@ -769,32 +770,42 @@ static inline int netvsc_send_pkt(
if (out_channel->rescind) if (out_channel->rescind)
return -ENODEV; return -ENODEV;
/*
* It is possible that once we successfully place this packet
* on the ringbuffer, we may stop the queue. In that case, we want
* to notify the host independent of the xmit_more flag. We don't
* need to be precise here; in the worst case we may signal the host
* unnecessarily.
*/
if (ring_avail < (RING_AVAIL_PERCENT_LOWATER + 1))
packet->xmit_more = false;
if (packet->page_buf_cnt) { if (packet->page_buf_cnt) {
pgbuf = packet->cp_partial ? packet->page_buf + pgbuf = packet->cp_partial ? packet->page_buf +
packet->rmsg_pgcnt : packet->page_buf; packet->rmsg_pgcnt : packet->page_buf;
ret = vmbus_sendpacket_pagebuffer(out_channel, ret = vmbus_sendpacket_pagebuffer_ctl(out_channel,
pgbuf, pgbuf,
packet->page_buf_cnt, packet->page_buf_cnt,
&nvmsg, &nvmsg,
sizeof(struct nvsp_message), sizeof(struct nvsp_message),
req_id); req_id,
VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED,
!packet->xmit_more);
} else { } else {
ret = vmbus_sendpacket( ret = vmbus_sendpacket_ctl(out_channel, &nvmsg,
out_channel, &nvmsg, sizeof(struct nvsp_message),
sizeof(struct nvsp_message), req_id,
req_id, VM_PKT_DATA_INBAND,
VM_PKT_DATA_INBAND, VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED,
VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); !packet->xmit_more);
} }
if (ret == 0) { if (ret == 0) {
atomic_inc(&net_device->num_outstanding_sends); atomic_inc(&net_device->num_outstanding_sends);
atomic_inc(&net_device->queue_sends[q_idx]); atomic_inc(&net_device->queue_sends[q_idx]);
if (hv_ringbuf_avail_percent(&out_channel->outbound) < if (ring_avail < RING_AVAIL_PERCENT_LOWATER) {
RING_AVAIL_PERCENT_LOWATER) { netif_tx_stop_queue(netdev_get_tx_queue(ndev, q_idx));
netif_tx_stop_queue(netdev_get_tx_queue(
ndev, q_idx));
if (atomic_read(&net_device-> if (atomic_read(&net_device->
queue_sends[q_idx]) < 1) queue_sends[q_idx]) < 1)