The live XDP frame code in BPF_PROG_RUN suffered from suboptimal cache
line placement due to the forced cache line alignment of struct
xdp_rxq_info. Rearrange things so we don't waste a whole cache line on
padding, and also add explicit alignment to the data_hard_start field in
the start-of-page data structure we use for the data pages.
Signed-off-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
---
net/bpf/test_run.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index c742869a0612..d153a3b3528f 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -108,12 +108,12 @@ struct xdp_page_head {
/* ::data_hard_start starts here */
DECLARE_FLEX_ARRAY(struct xdp_frame, frame);
DECLARE_FLEX_ARRAY(u8, data);
- };
+ } ____cacheline_aligned;
};
struct xdp_test_data {
- struct xdp_buff *orig_ctx;
struct xdp_rxq_info rxq;
+ struct xdp_buff *orig_ctx;
struct net_device *dev;
struct xdp_frame **frames;
struct sk_buff **skbs;
--
2.43.0
