hv_netvsc: Implement partial copy into send buffer
If remaining space in a send buffer slot is too small for the whole message,
we only copy the RNDIS header and PPI data into send buffer, so we can batch
one more packet each time. It reduces the vmbus per-message overhead.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index f0b8b3e..a10b316 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -132,6 +132,8 @@
bool is_data_pkt;
bool xmit_more; /* from skb */
+ bool cp_partial; /* partial copy into send buffer */
+
u16 vlan_tci;
u16 q_idx;
@@ -146,6 +148,9 @@
/* This points to the memory after page_buf */
struct rndis_message *rndis_msg;
+ u32 rmsg_size; /* RNDIS header and PPI size */
+ u32 rmsg_pgcnt; /* page count of RNDIS header and PPI */
+
u32 total_data_buflen;
/* Points to the send/receive buffer where the ethernet frame is */
void *data;
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 4d4d497..2e8ad06 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -703,15 +703,18 @@
u32 msg_size = 0;
u32 padding = 0;
u32 remain = packet->total_data_buflen % net_device->pkt_align;
+ u32 page_count = packet->cp_partial ? packet->rmsg_pgcnt :
+ packet->page_buf_cnt;
/* Add padding */
- if (packet->is_data_pkt && packet->xmit_more && remain) {
+ if (packet->is_data_pkt && packet->xmit_more && remain &&
+ !packet->cp_partial) {
padding = net_device->pkt_align - remain;
packet->rndis_msg->msg_len += padding;
packet->total_data_buflen += padding;
}
- for (i = 0; i < packet->page_buf_cnt; i++) {
+ for (i = 0; i < page_count; i++) {
char *src = phys_to_virt(packet->page_buf[i].pfn << PAGE_SHIFT);
u32 offset = packet->page_buf[i].offset;
u32 len = packet->page_buf[i].len;
@@ -739,6 +742,7 @@
struct net_device *ndev = net_device->ndev;
u64 req_id;
int ret;
+ struct hv_page_buffer *pgbuf;
nvmsg.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
if (packet->is_data_pkt) {
@@ -766,8 +770,10 @@
return -ENODEV;
if (packet->page_buf_cnt) {
+ pgbuf = packet->cp_partial ? packet->page_buf +
+ packet->rmsg_pgcnt : packet->page_buf;
ret = vmbus_sendpacket_pagebuffer(out_channel,
- packet->page_buf,
+ pgbuf,
packet->page_buf_cnt,
&nvmsg,
sizeof(struct nvsp_message),
@@ -824,6 +830,7 @@
unsigned long flag;
struct multi_send_data *msdp;
struct hv_netvsc_packet *msd_send = NULL, *cur_send = NULL;
+ bool try_batch;
net_device = get_outbound_net_device(device);
if (!net_device)
@@ -837,6 +844,7 @@
}
packet->channel = out_channel;
packet->send_buf_index = NETVSC_INVALID_INDEX;
+ packet->cp_partial = false;
msdp = &net_device->msd[q_idx];
@@ -845,12 +853,18 @@
if (msdp->pkt)
msd_len = msdp->pkt->total_data_buflen;
- if (packet->is_data_pkt && msd_len > 0 &&
- msdp->count < net_device->max_pkt &&
- msd_len + pktlen + net_device->pkt_align <
+ try_batch = packet->is_data_pkt && msd_len > 0 && msdp->count <
+ net_device->max_pkt;
+
+ if (try_batch && msd_len + pktlen + net_device->pkt_align <
net_device->send_section_size) {
section_index = msdp->pkt->send_buf_index;
+ } else if (try_batch && msd_len + packet->rmsg_size <
+ net_device->send_section_size) {
+ section_index = msdp->pkt->send_buf_index;
+ packet->cp_partial = true;
+
} else if (packet->is_data_pkt && pktlen + net_device->pkt_align <
net_device->send_section_size) {
section_index = netvsc_get_next_send_section(net_device);
@@ -866,22 +880,26 @@
netvsc_copy_to_send_buf(net_device,
section_index, msd_len,
packet);
- if (!packet->part_of_skb) {
- skb = (struct sk_buff *)
- (unsigned long)
- packet->send_completion_tid;
- packet->send_completion_tid = 0;
- }
-
- packet->page_buf_cnt = 0;
packet->send_buf_index = section_index;
- packet->total_data_buflen += msd_len;
+
+ if (packet->cp_partial) {
+ packet->page_buf_cnt -= packet->rmsg_pgcnt;
+ packet->total_data_buflen = msd_len + packet->rmsg_size;
+ } else {
+ packet->page_buf_cnt = 0;
+ packet->total_data_buflen += msd_len;
+ if (!packet->part_of_skb) {
+ skb = (struct sk_buff *)(unsigned long)packet->
+ send_completion_tid;
+ packet->send_completion_tid = 0;
+ }
+ }
if (msdp->pkt)
netvsc_xmit_completion(msdp->pkt);
- if (packet->xmit_more) {
+ if (packet->xmit_more && !packet->cp_partial) {
msdp->pkt = packet;
msdp->count++;
} else {
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 4487167..a3a9d38 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -277,15 +277,16 @@
}
static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
- struct hv_page_buffer *pb)
+ struct hv_netvsc_packet *packet)
{
+ struct hv_page_buffer *pb = packet->page_buf;
u32 slots_used = 0;
char *data = skb->data;
int frags = skb_shinfo(skb)->nr_frags;
int i;
/* The packet is laid out thus:
- * 1. hdr
+ * 1. hdr: RNDIS header and PPI
* 2. skb linear data
* 3. skb fragment data
*/
@@ -294,6 +295,9 @@
offset_in_page(hdr),
len, &pb[slots_used]);
+ packet->rmsg_size = len;
+ packet->rmsg_pgcnt = slots_used;
+
slots_used += fill_pg_buf(virt_to_page(data),
offset_in_page(data),
skb_headlen(skb), &pb[slots_used]);
@@ -578,7 +582,7 @@
rndis_msg->msg_len += rndis_msg_size;
packet->total_data_buflen = rndis_msg->msg_len;
packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
- skb, &page_buf[0]);
+ skb, packet);
ret = netvsc_send(net_device_ctx->device_ctx, packet);
