Re: [PATCH v2] virtio_net: bulk free tx skbs

[David Miller]

From: "Michael S. Tsirkin" 
Date: Thu, 17 Jan 2019 23:20:07 -0500

> Use napi_consume_skb() to get bulk free.  Note that napi_consume_skb is
> safe to call in a non-napi context as long as the napi_budget flag is
> correct.
> 
> Signed-off-by: Michael S. Tsirkin 

Applied, thanks.

Re: [PATCH v2] virtio_net: bulk free tx skbs

[Jason Wang]

On 2019/1/18 下午12:20, Michael S. Tsirkin wrote:

Use napi_consume_skb() to get bulk free.  Note that napi_consume_skb is
safe to call in a non-napi context as long as the napi_budget flag is
correct.

Signed-off-by: Michael S. Tsirkin 
---

Changes from v1:
rebase on master.

lightly tested on developer's box.

  drivers/net/virtio_net.c | 12 ++--
  1 file changed, 6 insertions(+), 6 deletions(-)



Acked-by: Jason Wang 




diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 023725086046..8fadd8eaf601 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1330,7 +1330,7 @@ static int virtnet_receive(struct receive_queue *rq, int 
budget,
return stats.packets;
  }
  
-static void free_old_xmit_skbs(struct send_queue *sq)

+static void free_old_xmit_skbs(struct send_queue *sq, bool in_napi)
  {
struct sk_buff *skb;
unsigned int len;
@@ -1343,7 +1343,7 @@ static void free_old_xmit_skbs(struct send_queue *sq)
bytes += skb->len;
packets++;
  
-		dev_consume_skb_any(skb);

+   napi_consume_skb(skb, in_napi);
}
  
  	/* Avoid overhead when no packets have been processed

@@ -1369,7 +1369,7 @@ static void virtnet_poll_cleantx(struct receive_queue *rq)
return;
  
  	if (__netif_tx_trylock(txq)) {

-   free_old_xmit_skbs(sq);
+   free_old_xmit_skbs(sq, true);
__netif_tx_unlock(txq);
}
  
@@ -1445,7 +1445,7 @@ static int virtnet_poll_tx(struct napi_struct *napi, int budget)

struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, vq2txq(sq->vq));
  
  	__netif_tx_lock(txq, raw_smp_processor_id());

-   free_old_xmit_skbs(sq);
+   free_old_xmit_skbs(sq, true);
__netif_tx_unlock(txq);
  
  	virtqueue_napi_complete(napi, sq->vq, 0);

@@ -1514,7 +1514,7 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct 
net_device *dev)
bool use_napi = sq->napi.weight;
  
  	/* Free up any pending old buffers before queueing new ones. */

-   free_old_xmit_skbs(sq);
+   free_old_xmit_skbs(sq, false);
  
  	if (use_napi && kick)

virtqueue_enable_cb_delayed(sq->vq);
@@ -1557,7 +1557,7 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct 
net_device *dev)
if (!use_napi &&
unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
/* More just got used, free them then recheck. */
-   free_old_xmit_skbs(sq);
+   free_old_xmit_skbs(sq, false);
if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
netif_start_subqueue(dev, qnum);
virtqueue_disable_cb(sq->vq);

[PATCH v2] virtio_net: bulk free tx skbs

[Michael S. Tsirkin]

Use napi_consume_skb() to get bulk free.  Note that napi_consume_skb is
safe to call in a non-napi context as long as the napi_budget flag is
correct.

Signed-off-by: Michael S. Tsirkin 
---

Changes from v1:
rebase on master.

lightly tested on developer's box.

 drivers/net/virtio_net.c | 12 ++--
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 023725086046..8fadd8eaf601 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1330,7 +1330,7 @@ static int virtnet_receive(struct receive_queue *rq, int 
budget,
return stats.packets;
 }
 
-static void free_old_xmit_skbs(struct send_queue *sq)
+static void free_old_xmit_skbs(struct send_queue *sq, bool in_napi)
 {
struct sk_buff *skb;
unsigned int len;
@@ -1343,7 +1343,7 @@ static void free_old_xmit_skbs(struct send_queue *sq)
bytes += skb->len;
packets++;
 
-   dev_consume_skb_any(skb);
+   napi_consume_skb(skb, in_napi);
}
 
/* Avoid overhead when no packets have been processed
@@ -1369,7 +1369,7 @@ static void virtnet_poll_cleantx(struct receive_queue *rq)
return;
 
if (__netif_tx_trylock(txq)) {
-   free_old_xmit_skbs(sq);
+   free_old_xmit_skbs(sq, true);
__netif_tx_unlock(txq);
}
 
@@ -1445,7 +1445,7 @@ static int virtnet_poll_tx(struct napi_struct *napi, int 
budget)
struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, vq2txq(sq->vq));
 
__netif_tx_lock(txq, raw_smp_processor_id());
-   free_old_xmit_skbs(sq);
+   free_old_xmit_skbs(sq, true);
__netif_tx_unlock(txq);
 
virtqueue_napi_complete(napi, sq->vq, 0);
@@ -1514,7 +1514,7 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct 
net_device *dev)
bool use_napi = sq->napi.weight;
 
/* Free up any pending old buffers before queueing new ones. */
-   free_old_xmit_skbs(sq);
+   free_old_xmit_skbs(sq, false);
 
if (use_napi && kick)
virtqueue_enable_cb_delayed(sq->vq);
@@ -1557,7 +1557,7 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct 
net_device *dev)
if (!use_napi &&
unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
/* More just got used, free them then recheck. */
-   free_old_xmit_skbs(sq);
+   free_old_xmit_skbs(sq, false);
if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
netif_start_subqueue(dev, qnum);
virtqueue_disable_cb(sq->vq);
-- 
MST