Commit 15a863bf authored by stephen hemminger's avatar stephen hemminger Committed by David S. Miller
Browse files

netvsc: implement NAPI 



Use NAPI (softirq), to handle receive packets and send completions.
Previously this was handled by tasklet.

Signed-off-by: default avatarStephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f3dd3f47

drivers/net/hyperv/hyperv_net.h

+2 −0
Original line number Diff line number Diff line
@@ -196,6 +196,7 @@ int netvsc_recv_callback(struct net_device *net, 
			 const struct ndis_tcp_ip_checksum_info *csum_info,

			 const struct ndis_pkt_8021q_info *vlan);

void netvsc_channel_cb(void *context);

int netvsc_poll(struct napi_struct *napi, int budget);

int rndis_filter_open(struct netvsc_device *nvdev);

int rndis_filter_close(struct netvsc_device *nvdev);

int rndis_filter_device_add(struct hv_device *dev,
@@ -720,6 +721,7 @@ struct net_device_context { 
/* Per channel data */

struct netvsc_channel {

	struct vmbus_channel *channel;

	struct napi_struct napi;

	struct multi_send_data msd;

	struct multi_recv_comp mrc;

	atomic_t queue_sends;

drivers/net/hyperv/netvsc.c

+98 −42
Original line number Diff line number Diff line
@@ -556,6 +556,7 @@ void netvsc_device_remove(struct hv_device *device) 
	struct net_device *ndev = hv_get_drvdata(device);

	struct net_device_context *net_device_ctx = netdev_priv(ndev);

	struct netvsc_device *net_device = net_device_ctx->nvdev;

	int i;



	netvsc_disconnect_vsp(device);
@@ -570,6 +571,9 @@ void netvsc_device_remove(struct hv_device *device) 
	/* Now, we can close the channel safely */

	vmbus_close(device->channel);



	for (i = 0; i < VRSS_CHANNEL_MAX; i++)

		napi_disable(&net_device->chan_table[0].napi);



	/* Release all resources */

	free_netvsc_device(net_device);

}
@@ -1063,7 +1067,7 @@ static inline struct recv_comp_data *get_recv_comp_slot( 
	return rcd;

}



static void netvsc_receive(struct net_device *ndev,

static int netvsc_receive(struct net_device *ndev,

		   struct netvsc_device *net_device,

		   struct net_device_context *net_device_ctx,

		   struct hv_device *device,
@@ -1073,20 +1077,19 @@ static void netvsc_receive(struct net_device *ndev, 
{

	const struct vmtransfer_page_packet_header *vmxferpage_packet

		= container_of(desc, const struct vmtransfer_page_packet_header, d);

	u16 q_idx = channel->offermsg.offer.sub_channel_index;

	char *recv_buf = net_device->recv_buf;

	u32 status = NVSP_STAT_SUCCESS;

	int i;

	int count = 0;

	int ret;

	struct recv_comp_data *rcd;

	u16 q_idx = channel->offermsg.offer.sub_channel_index;



	/* Make sure this is a valid nvsp packet */

	if (unlikely(nvsp->hdr.msg_type != NVSP_MSG1_TYPE_SEND_RNDIS_PKT)) {

		netif_err(net_device_ctx, rx_err, ndev,

			  "Unknown nvsp packet type received %u\n",

			  nvsp->hdr.msg_type);

		return;

		return 0;

	}



	if (unlikely(vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID)) {
@@ -1094,7 +1097,7 @@ static void netvsc_receive(struct net_device *ndev, 
			  "Invalid xfer page set id - expecting %x got %x\n",

			  NETVSC_RECEIVE_BUFFER_ID,

			  vmxferpage_packet->xfer_pageset_id);

		return;

		return 0;

	}



	count = vmxferpage_packet->range_cnt;
@@ -1110,26 +1113,26 @@ static void netvsc_receive(struct net_device *ndev, 
					      channel, data, buflen);

	}



	if (!net_device->chan_table[q_idx].mrc.buf) {

	if (net_device->chan_table[q_idx].mrc.buf) {

		struct recv_comp_data *rcd;



		rcd = get_recv_comp_slot(net_device, channel, q_idx);

		if (rcd) {

			rcd->tid = vmxferpage_packet->d.trans_id;

			rcd->status = status;

		} else {

			netdev_err(ndev, "Recv_comp full buf q:%hd, tid:%llx\n",

				   q_idx, vmxferpage_packet->d.trans_id);

		}

	} else {

		ret = netvsc_send_recv_completion(channel,

						  vmxferpage_packet->d.trans_id,

						  status);

		if (ret)

			netdev_err(ndev, "Recv_comp q:%hd, tid:%llx, err:%d\n",

				   q_idx, vmxferpage_packet->d.trans_id, ret);

		return;

	}



	rcd = get_recv_comp_slot(net_device, channel, q_idx);



	if (!rcd) {

		netdev_err(ndev, "Recv_comp full buf q:%hd, tid:%llx\n",

			   q_idx, vmxferpage_packet->d.trans_id);

		return;

	}



	rcd->tid = vmxferpage_packet->d.trans_id;

	rcd->status = status;

	return count;

}



static void netvsc_send_table(struct hv_device *hdev,
@@ -1179,7 +1182,7 @@ static inline void netvsc_receive_inband(struct hv_device *hdev, 
	}

}



static void netvsc_process_raw_pkt(struct hv_device *device,

static int netvsc_process_raw_pkt(struct hv_device *device,

				  struct vmbus_channel *channel,

				  struct netvsc_device *net_device,

				  struct net_device *ndev,
@@ -1195,7 +1198,7 @@ static void netvsc_process_raw_pkt(struct hv_device *device, 
		break;



	case VM_PKT_DATA_USING_XFER_PAGES:

		netvsc_receive(ndev, net_device, net_device_ctx,

		return netvsc_receive(ndev, net_device, net_device_ctx,

				      device, channel, desc, nvmsg);

		break;
@@ -1208,22 +1211,64 @@ static void netvsc_process_raw_pkt(struct hv_device *device, 
			   desc->type, request_id);

		break;

	}



	return 0;

}



static struct hv_device *netvsc_channel_to_device(struct vmbus_channel *channel)

{

	struct vmbus_channel *primary = channel->primary_channel;



	return primary ? primary->device_obj : channel->device_obj;

}



int netvsc_poll(struct napi_struct *napi, int budget)

{

	struct netvsc_channel *nvchan

		= container_of(napi, struct netvsc_channel, napi);

	struct vmbus_channel *channel = nvchan->channel;

	struct hv_device *device = netvsc_channel_to_device(channel);

	u16 q_idx = channel->offermsg.offer.sub_channel_index;

	struct net_device *ndev = hv_get_drvdata(device);

	struct netvsc_device *net_device = net_device_to_netvsc_device(ndev);

	const struct vmpacket_descriptor *desc;

	int work_done = 0;



	desc = hv_pkt_iter_first(channel);

	while (desc) {

		int count;



		count = netvsc_process_raw_pkt(device, channel, net_device,

					       ndev, desc->trans_id, desc);

		work_done += count;

		desc = __hv_pkt_iter_next(channel, desc);



		/* If receive packet budget is exhausted, reschedule */

		if (work_done >= budget) {

			work_done = budget;

			break;

		}

	}

	hv_pkt_iter_close(channel);



	/* If ring is empty and NAPI is not doing polling */

	if (work_done < budget &&

	    napi_complete_done(napi, work_done) &&

	    hv_end_read(&channel->inbound) != 0)

		napi_reschedule(napi);



	netvsc_chk_recv_comp(net_device, channel, q_idx);

	return work_done;

}



void netvsc_channel_cb(void *context)

{

	struct vmbus_channel *channel = context;

	struct hv_device *device = netvsc_channel_to_device(channel);

	u16 q_idx = channel->offermsg.offer.sub_channel_index;

	struct hv_device *device;

	struct netvsc_device *net_device;

	struct vmpacket_descriptor *desc;

	struct net_device *ndev;



	if (channel->primary_channel != NULL)

		device = channel->primary_channel->device_obj;

	else

		device = channel->device_obj;



	ndev = hv_get_drvdata(device);

	if (unlikely(!ndev))

		return;
@@ -1233,13 +1278,9 @@ void netvsc_channel_cb(void *context) 
	    netvsc_channel_idle(net_device, q_idx))

		return;



	foreach_vmbus_pkt(desc, channel) {

		netvsc_process_raw_pkt(device, channel, net_device,

				       ndev, desc->trans_id, desc);



	}



	netvsc_chk_recv_comp(net_device, channel, q_idx);

	/* disable interupts from host */

	hv_begin_read(&channel->inbound);

	napi_schedule(&net_device->chan_table[q_idx].napi);

}



/*
@@ -1261,6 +1302,11 @@ int netvsc_device_add(struct hv_device *device, 


	net_device->ring_size = ring_size;



	/* Because the device uses NAPI, all the interrupt batching and

	 * control is done via Net softirq, not the channel handling

	 */

	set_channel_read_mode(device->channel, HV_CALL_ISR);



	/* Open the channel */

	ret = vmbus_open(device->channel, ring_size * PAGE_SIZE,

			 ring_size * PAGE_SIZE, NULL, 0,
@@ -1278,8 +1324,16 @@ int netvsc_device_add(struct hv_device *device, 
	 * chn_table with the default channel to use it before subchannels are

	 * opened.

	 */

	for (i = 0; i < VRSS_CHANNEL_MAX; i++)

		net_device->chan_table[i].channel = device->channel;

	for (i = 0; i < VRSS_CHANNEL_MAX; i++) {

		struct netvsc_channel *nvchan = &net_device->chan_table[i];



		nvchan->channel = device->channel;

		netif_napi_add(ndev, &nvchan->napi,

			       netvsc_poll, NAPI_POLL_WEIGHT);

	}



	/* Enable NAPI handler for init callbacks */

	napi_enable(&net_device->chan_table[0].napi);



	/* Writing nvdev pointer unlocks netvsc_send(), make sure chn_table is

	 * populated.
@@ -1299,6 +1353,8 @@ int netvsc_device_add(struct hv_device *device, 
	return ret;



close:

	napi_disable(&net_device->chan_table[0].napi);



	/* Now, we can close the channel safely */

	vmbus_close(device->channel);

drivers/net/hyperv/netvsc_drv.c

+0 −5
Original line number Diff line number Diff line
@@ -690,11 +690,6 @@ int netvsc_recv_callback(struct net_device *net, 
		++rx_stats->multicast;

	u64_stats_update_end(&rx_stats->syncp);



	/*

	 * Pass the skb back up. Network stack will deallocate the skb when it

	 * is done.

	 * TODO - use NAPI?

	 */

	netif_receive_skb(skb);

	rcu_read_unlock();

drivers/net/hyperv/rndis_filter.c

+2 −0
Original line number Diff line number Diff line
@@ -1012,6 +1012,8 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc) 
	if (ret == 0)

		nvscdev->chan_table[chn_index].channel = new_sc;



	napi_enable(&nvscdev->chan_table[chn_index].napi);



	spin_lock_irqsave(&nvscdev->sc_lock, flags);

	nvscdev->num_sc_offered--;

	spin_unlock_irqrestore(&nvscdev->sc_lock, flags);