This is a note to let you know that I've just added the patch titled
net: ena: Do not waste napi skb cache
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-ena-do-not-waste-napi-skb-cache.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9082b0cad5261964a74a0a18c3e3b3dff4242bb4
Author: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
Date: Sat Jan 29 08:53:36 2022 +0000
net: ena: Do not waste napi skb cache
[ Upstream commit 7354a426e063e108c0a3590f13abc77573172576 ]
By profiling, discovered that ena device driver allocates skb by
build_skb() and frees by napi_skb_cache_put(). Because the driver
does not use napi skb cache in allocation path, napi skb cache is
periodically filled and flushed. This is waste of napi skb cache.
As ena_alloc_skb() is called only in napi, Use napi_build_skb()
and napi_alloc_skb() when allocating skb.
This patch was tested on aws a1.metal instance.
[ jwiedmann.dev@xxxxxxxxx: Use napi_alloc_skb() instead of
netdev_alloc_skb_ip_align() to keep things consistent. ]
Signed-off-by: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
Acked-by: Shay Agroskin <shayagr@xxxxxxxxxx>
Link: https://lore.kernel.org/r/YfUAkA9BhyOJRT4B@xxxxxxxxxxxxxxxxxxx-northeast-1.compute.internal
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Stable-dep-of: 2dc8b1e7177d ("net: ena: Fix redundant device NUMA node override")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c
index cf8148a159ee0..e2b43d0f90784 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -1418,10 +1418,9 @@ static struct sk_buff *ena_alloc_skb(struct ena_ring *rx_ring, void *first_frag)
struct sk_buff *skb;
if (!first_frag)
- skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
- rx_ring->rx_copybreak);
+ skb = napi_alloc_skb(rx_ring->napi, rx_ring->rx_copybreak);
else
- skb = build_skb(first_frag, ENA_PAGE_SIZE);
+ skb = napi_build_skb(first_frag, ENA_PAGE_SIZE);
if (unlikely(!skb)) {
ena_increase_stat(&rx_ring->rx_stats.skb_alloc_fail, 1,
