napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order
to save some cycles on freeing/allocating skbuff_heads on every
new Rx or completed Tx.
iavf driver runs Tx completion polling cycle right before the Rx
one and uses napi_consume_skb() to feed the cache with skbuff_heads
of completed entries, so it's never empty and always warm at that
moment. Switch to the napi_build_skb() to relax mm pressure on
heavy Rx.
Signed-off-by: Alexander Lobakin <[email protected]>
Reviewed-by: Michal Swiatkowski <[email protected]>
---
drivers/net/ethernet/intel/iavf/iavf_txrx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.c b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
index 3525eab8e9f9..90fdd828e5d8 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_txrx.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
@@ -1363,7 +1363,7 @@ static struct sk_buff *iavf_build_skb(struct iavf_ring *rx_ring,
net_prefetch(va);
/* build an skb around the page buffer */
- skb = build_skb(va - IAVF_SKB_PAD, truesize);
+ skb = napi_build_skb(va - IAVF_SKB_PAD, truesize);
if (unlikely(!skb))
return NULL;
--
2.33.1
> -----Original Message-----
> From: Intel-wired-lan <[email protected]> On Behalf Of
> Alexander Lobakin
> Sent: wtorek, 23 listopada 2021 18:19
> To: [email protected]
> Cc: [email protected]; [email protected]; Jakub Kicinski
> <[email protected]>; David S. Miller <[email protected]>
> Subject: [Intel-wired-lan] [PATCH net-next 4/9] iavf: switch to
> napi_build_skb()
>
> napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order to save
> some cycles on freeing/allocating skbuff_heads on every new Rx or
> completed Tx.
> iavf driver runs Tx completion polling cycle right before the Rx one and uses
> napi_consume_skb() to feed the cache with skbuff_heads of completed
> entries, so it's never empty and always warm at that moment. Switch to the
> napi_build_skb() to relax mm pressure on heavy Rx.
>
> Signed-off-by: Alexander Lobakin <[email protected]>
> Reviewed-by: Michal Swiatkowski <[email protected]>
> ---
> drivers/net/ethernet/intel/iavf/iavf_txrx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> index 3525eab8e9f9..90fdd828e5d8 100644
> --- a/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> +++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> @@ -1363,7 +1363,7 @@ static struct sk_buff *iavf_build_skb(struct
Tested-by: Konrad Jankowski <[email protected]>