[PATCH v2] virtio_net: simplify tx queue wake condition check

[PATCH v2] virtio_net: simplify tx queue wake condition check

[liming.wu]

From: Liming Wu <liming.wu@jaguarmicro.com>

Consolidate the two nested if conditions for checking tx queue wake
conditions into a single combined condition. This improves code
readability without changing functionality. And move netif_tx_wake_queue
into if condition to reduce unnecessary checks for queue stops.

Signed-off-by: Liming Wu <liming.wu@jaguarmicro.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
---
 drivers/net/virtio_net.c | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 5d674eb9a0f2..07a378220643 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -3021,12 +3021,11 @@ static void virtnet_poll_cleantx(struct receive_queue *rq, int budget)
 			free_old_xmit(sq, txq, !!budget);
 		} while (unlikely(!virtqueue_enable_cb_delayed(sq->vq)));
 
-		if (sq->vq->num_free >= MAX_SKB_FRAGS + 2) {
-			if (netif_tx_queue_stopped(txq)) {
-				u64_stats_update_begin(&sq->stats.syncp);
-				u64_stats_inc(&sq->stats.wake);
-				u64_stats_update_end(&sq->stats.syncp);
-			}
+		if (sq->vq->num_free >= MAX_SKB_FRAGS + 2 &&
+		    netif_tx_queue_stopped(txq)) {
+			u64_stats_update_begin(&sq->stats.syncp);
+			u64_stats_inc(&sq->stats.wake);
+			u64_stats_update_end(&sq->stats.syncp);
 			netif_tx_wake_queue(txq);
 		}
 
@@ -3218,12 +3217,11 @@ static int virtnet_poll_tx(struct napi_struct *napi, int budget)
 	else
 		free_old_xmit(sq, txq, !!budget);
 
-	if (sq->vq->num_free >= MAX_SKB_FRAGS + 2) {
-		if (netif_tx_queue_stopped(txq)) {
-			u64_stats_update_begin(&sq->stats.syncp);
-			u64_stats_inc(&sq->stats.wake);
-			u64_stats_update_end(&sq->stats.syncp);
-		}
+	if (sq->vq->num_free >= MAX_SKB_FRAGS + 2 &&
+	    netif_tx_queue_stopped(txq)) {
+		u64_stats_update_begin(&sq->stats.syncp);
+		u64_stats_inc(&sq->stats.wake);
+		u64_stats_update_end(&sq->stats.syncp);
 		netif_tx_wake_queue(txq);
 	}
 
-- 
2.34.1

Re: [PATCH v2] virtio_net: simplify tx queue wake condition check

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Thu, 10 Jul 2025 10:32:08 +0800 you wrote:
> From: Liming Wu <liming.wu@jaguarmicro.com>
> 
> Consolidate the two nested if conditions for checking tx queue wake
> conditions into a single combined condition. This improves code
> readability without changing functionality. And move netif_tx_wake_queue
> into if condition to reduce unnecessary checks for queue stops.
> 
> [...]

Here is the summary with links:
  - [v2] virtio_net: simplify tx queue wake condition check
    https://git.kernel.org/netdev/net-next/c/2f82e9954662

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

Re: [PATCH v2] virtio_net: simplify tx queue wake condition check

[Lei Yang]

Tested this series of patches v2 with virtio-net regression tests,
everything works fine.

Tested-by: Lei Yang <leiyang@redhat.com>

On Thu, Jul 10, 2025 at 10:32 AM <liming.wu@jaguarmicro.com> wrote:
>
> From: Liming Wu <liming.wu@jaguarmicro.com>
>
> Consolidate the two nested if conditions for checking tx queue wake
> conditions into a single combined condition. This improves code
> readability without changing functionality. And move netif_tx_wake_queue
> into if condition to reduce unnecessary checks for queue stops.
>
> Signed-off-by: Liming Wu <liming.wu@jaguarmicro.com>
> Tested-by: Lei Yang <leiyang@redhat.com>
> Acked-by: Jason Wang <jasowang@redhat.com>
> ---
>  drivers/net/virtio_net.c | 22 ++++++++++------------
>  1 file changed, 10 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 5d674eb9a0f2..07a378220643 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -3021,12 +3021,11 @@ static void virtnet_poll_cleantx(struct receive_queue *rq, int budget)
>                         free_old_xmit(sq, txq, !!budget);
>                 } while (unlikely(!virtqueue_enable_cb_delayed(sq->vq)));
>
> -               if (sq->vq->num_free >= MAX_SKB_FRAGS + 2) {
> -                       if (netif_tx_queue_stopped(txq)) {
> -                               u64_stats_update_begin(&sq->stats.syncp);
> -                               u64_stats_inc(&sq->stats.wake);
> -                               u64_stats_update_end(&sq->stats.syncp);
> -                       }
> +               if (sq->vq->num_free >= MAX_SKB_FRAGS + 2 &&
> +                   netif_tx_queue_stopped(txq)) {
> +                       u64_stats_update_begin(&sq->stats.syncp);
> +                       u64_stats_inc(&sq->stats.wake);
> +                       u64_stats_update_end(&sq->stats.syncp);
>                         netif_tx_wake_queue(txq);
>                 }
>
> @@ -3218,12 +3217,11 @@ static int virtnet_poll_tx(struct napi_struct *napi, int budget)
>         else
>                 free_old_xmit(sq, txq, !!budget);
>
> -       if (sq->vq->num_free >= MAX_SKB_FRAGS + 2) {
> -               if (netif_tx_queue_stopped(txq)) {
> -                       u64_stats_update_begin(&sq->stats.syncp);
> -                       u64_stats_inc(&sq->stats.wake);
> -                       u64_stats_update_end(&sq->stats.syncp);
> -               }
> +       if (sq->vq->num_free >= MAX_SKB_FRAGS + 2 &&
> +           netif_tx_queue_stopped(txq)) {
> +               u64_stats_update_begin(&sq->stats.syncp);
> +               u64_stats_inc(&sq->stats.wake);
> +               u64_stats_update_end(&sq->stats.syncp);
>                 netif_tx_wake_queue(txq);
>         }
>
> --
> 2.34.1
>