6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Roger Quadros <rogerq@xxxxxxxxxx>
[ Upstream commit 5db843258de1e4e6b1ef1cbd1797923c9e3de548 ]
If the XDP program doesn't result in XDP_PASS then we leak the
memory allocated by am65_cpsw_build_skb().
It is pointless to allocate SKB memory before running the XDP
program as we would be wasting CPU cycles for cases other than XDP_PASS.
Move the SKB allocation after evaluating the XDP program result.
This fixes the memleak. A performance boost is seen for XDP_DROP test.
XDP_DROP test:
Before: 460256 rx/s 0 err/s
After: 784130 rx/s 0 err/s
Fixes: 8acacc40f733 ("net: ethernet: ti: am65-cpsw: Add minimal XDP support")
Signed-off-by: Roger Quadros <rogerq@xxxxxxxxxx>
Link: https://patch.msgid.link/20250210-am65-cpsw-xdp-fixes-v1-1-ec6b1f7f1aca@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/ti/am65-cpsw-nuss.c | 26 ++++++++++++------------
1 file changed, 13 insertions(+), 13 deletions(-)
diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index 3c0d067c36099..14df3c0141679 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -599,7 +599,8 @@ static void am65_cpsw_nuss_tx_cleanup(void *data, dma_addr_t desc_dma)
static struct sk_buff *am65_cpsw_build_skb(void *page_addr,
struct net_device *ndev,
- unsigned int len)
+ unsigned int len,
+ unsigned int headroom)
{
struct sk_buff *skb;
@@ -609,7 +610,7 @@ static struct sk_buff *am65_cpsw_build_skb(void *page_addr,
if (unlikely(!skb))
return NULL;
- skb_reserve(skb, AM65_CPSW_HEADROOM);
+ skb_reserve(skb, headroom);
skb->dev = ndev;
return skb;
@@ -1191,16 +1192,8 @@ static int am65_cpsw_nuss_rx_packets(struct am65_cpsw_rx_flow *flow,
dev_dbg(dev, "%s rx csum_info:%#x\n", __func__, csum_info);
dma_unmap_single(rx_chn->dma_dev, buf_dma, buf_dma_len, DMA_FROM_DEVICE);
-
k3_cppi_desc_pool_free(rx_chn->desc_pool, desc_rx);
- skb = am65_cpsw_build_skb(page_addr, ndev,
- AM65_CPSW_MAX_PACKET_SIZE);
- if (unlikely(!skb)) {
- new_page = page;
- goto requeue;
- }
-
if (port->xdp_prog) {
xdp_init_buff(&xdp, PAGE_SIZE, &port->xdp_rxq[flow->id]);
xdp_prepare_buff(&xdp, page_addr, AM65_CPSW_HEADROOM,
@@ -1210,9 +1203,16 @@ static int am65_cpsw_nuss_rx_packets(struct am65_cpsw_rx_flow *flow,
if (*xdp_state != AM65_CPSW_XDP_PASS)
goto allocate;
- /* Compute additional headroom to be reserved */
- headroom = (xdp.data - xdp.data_hard_start) - skb_headroom(skb);
- skb_reserve(skb, headroom);
+ headroom = xdp.data - xdp.data_hard_start;
+ } else {
+ headroom = AM65_CPSW_HEADROOM;
+ }
+
+ skb = am65_cpsw_build_skb(page_addr, ndev,
+ AM65_CPSW_MAX_PACKET_SIZE, headroom);
+ if (unlikely(!skb)) {
+ new_page = page;
+ goto requeue;
}
ndev_priv = netdev_priv(ndev);
--
2.39.5
