[PATCH bpf-next v7 4/5] igc: Refactor empty packet insertion into a reusable function

From: Song Yoong Siang
Date: Mon Feb 03 2025 - 19:51:45 EST


Refactor the code for inserting an empty packet into a new function
igc_insert_empty_packet(). This change extracts the logic for inserting
an empty packet from igc_xmit_frame_ring() into a separate function,
allowing it to be reused in future implementations, such as the XDP
zero copy transmit function.

This patch introduces no functional changes.

Signed-off-by: Song Yoong Siang <yoong.siang.song@xxxxxxxxx>
---
drivers/net/ethernet/intel/igc/igc_main.c | 42 ++++++++++++-----------
1 file changed, 22 insertions(+), 20 deletions(-)

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 56a35d58e7a6..c3edd8bcf633 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -1566,6 +1566,26 @@ static bool igc_request_tx_tstamp(struct igc_adapter *adapter, struct sk_buff *s
return false;
}

+static void igc_insert_empty_packet(struct igc_ring *tx_ring)
+{
+ struct igc_tx_buffer *empty_info;
+ struct sk_buff *empty;
+ void *data;
+
+ empty_info = &tx_ring->tx_buffer_info[tx_ring->next_to_use];
+ empty = alloc_skb(IGC_EMPTY_FRAME_SIZE, GFP_ATOMIC);
+ if (!empty)
+ return;
+
+ data = skb_put(empty, IGC_EMPTY_FRAME_SIZE);
+ memset(data, 0, IGC_EMPTY_FRAME_SIZE);
+
+ igc_tx_ctxtdesc(tx_ring, 0, false, 0, 0, 0);
+
+ if (igc_init_tx_empty_descriptor(tx_ring, empty, empty_info) < 0)
+ dev_kfree_skb_any(empty);
+}
+
static netdev_tx_t igc_xmit_frame_ring(struct sk_buff *skb,
struct igc_ring *tx_ring)
{
@@ -1603,26 +1623,8 @@ static netdev_tx_t igc_xmit_frame_ring(struct sk_buff *skb,
skb->tstamp = ktime_set(0, 0);
launch_time = igc_tx_launchtime(tx_ring, txtime, &first_flag, &insert_empty);

- if (insert_empty) {
- struct igc_tx_buffer *empty_info;
- struct sk_buff *empty;
- void *data;
-
- empty_info = &tx_ring->tx_buffer_info[tx_ring->next_to_use];
- empty = alloc_skb(IGC_EMPTY_FRAME_SIZE, GFP_ATOMIC);
- if (!empty)
- goto done;
-
- data = skb_put(empty, IGC_EMPTY_FRAME_SIZE);
- memset(data, 0, IGC_EMPTY_FRAME_SIZE);
-
- igc_tx_ctxtdesc(tx_ring, 0, false, 0, 0, 0);
-
- if (igc_init_tx_empty_descriptor(tx_ring,
- empty,
- empty_info) < 0)
- dev_kfree_skb_any(empty);
- }
+ if (insert_empty)
+ igc_insert_empty_packet(tx_ring);

done:
/* record the location of the first descriptor for this packet */
--
2.34.1