[PATCH v2 net-next 3/3] net: ethernet: enetc: do not always access skb_shared_info in the XDP path
From: Lorenzo Bianconi <lorenzo@kernel.org>
Date: 2023-01-04 13:57:44
Subsystem:
freescale enetc ethernet drivers, networking drivers, the rest · Maintainers:
Claudiu Manoil, Vladimir Oltean, Wei Fang, Clark Wang, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Move XDP skb_shared_info structure initialization in from enetc_map_rx_buff_to_xdp() to enetc_add_rx_buff_to_xdp() and do not always access skb_shared_info in the xdp_buff/xdp_frame since it is located in a different cacheline with respect to hard_start and data xdp pointers. Rely on XDP_FLAGS_HAS_FRAGS flag to check if it really necessary to access non-linear part of the xdp_buff/xdp_frame. Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> --- drivers/net/ethernet/freescale/enetc/enetc.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index 18a01f6282b6..5ad0b259e623 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c@@ -1305,6 +1305,10 @@ static int enetc_xdp_frame_to_xdp_tx_swbd(struct enetc_bdr *tx_ring, xdp_tx_swbd->xdp_frame = NULL; n++; + + if (!xdp_frame_has_frags(xdp_frame)) + goto out; + xdp_tx_swbd = &xdp_tx_arr[n]; shinfo = xdp_get_shared_info_from_frame(xdp_frame);
@@ -1334,7 +1338,7 @@ static int enetc_xdp_frame_to_xdp_tx_swbd(struct enetc_bdr *tx_ring, n++; xdp_tx_swbd = &xdp_tx_arr[n]; } - +out: xdp_tx_arr[n - 1].is_eof = true; xdp_tx_arr[n - 1].xdp_frame = xdp_frame;
@@ -1390,16 +1394,12 @@ static void enetc_map_rx_buff_to_xdp(struct enetc_bdr *rx_ring, int i, { struct enetc_rx_swbd *rx_swbd = enetc_get_rx_buff(rx_ring, i, size); void *hard_start = page_address(rx_swbd->page) + rx_swbd->page_offset; - struct skb_shared_info *shinfo; /* To be used for XDP_TX */ rx_swbd->len = size; xdp_prepare_buff(xdp_buff, hard_start - rx_ring->buffer_offset, rx_ring->buffer_offset, size, false); - - shinfo = xdp_get_shared_info_from_buff(xdp_buff); - shinfo->nr_frags = 0; } static void enetc_add_rx_buff_to_xdp(struct enetc_bdr *rx_ring, int i,
@@ -1407,7 +1407,7 @@ static void enetc_add_rx_buff_to_xdp(struct enetc_bdr *rx_ring, int i, { struct skb_shared_info *shinfo = xdp_get_shared_info_from_buff(xdp_buff); struct enetc_rx_swbd *rx_swbd = enetc_get_rx_buff(rx_ring, i, size); - skb_frag_t *frag = &shinfo->frags[shinfo->nr_frags]; + skb_frag_t *frag; /* To be used for XDP_TX */ rx_swbd->len = size;
@@ -1415,6 +1415,7 @@ static void enetc_add_rx_buff_to_xdp(struct enetc_bdr *rx_ring, int i, if (!xdp_buff_has_frags(xdp_buff)) { xdp_buff_set_frags_flag(xdp_buff); shinfo->xdp_frags_size = size; + shinfo->nr_frags = 0; } else { shinfo->xdp_frags_size += size; }
@@ -1422,6 +1423,7 @@ static void enetc_add_rx_buff_to_xdp(struct enetc_bdr *rx_ring, int i, if (page_is_pfmemalloc(rx_swbd->page)) xdp_buff_set_frag_pfmemalloc(xdp_buff); + frag = &shinfo->frags[shinfo->nr_frags]; skb_frag_off_set(frag, rx_swbd->page_offset); skb_frag_size_set(frag, size); __skb_frag_set_page(frag, rx_swbd->page);
--
2.39.0