From: Jithu Joseph <jithu.joseph@xxxxxxxxx>
Adds Launchtime support in the XDP Zero copy Tx path.
If launchtime is enabled for the ring handling the
packet and if the launch-time data is present, programs
a context descriptor with the launchtime so that NIC
can transmit the packet at the appropriate time.
As for the non-ZC path, txtime info is copied into
skb->tstamp in the XDP layer and the existing Tx path
in the driver has support for honoring that.
Signed-off-by: Jithu Joseph <jithu.joseph@xxxxxxxxx>
---
drivers/net/ethernet/intel/igc/igc_main.c | 49 +++++++++++++++++++++--
1 file changed, 46 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index b7aab35c1132..336cf6bc0a71 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -2582,6 +2582,35 @@ static void igc_update_tx_stats(struct igc_q_vector *q_vector,
q_vector->tx.total_packets += packets;
}
+static void igc_launchtm_ctxtdesc(struct igc_ring *tx_ring,
+ ktime_t txtime)
+{
+ struct igc_adapter *adapter = netdev_priv(tx_ring->netdev);
+ struct igc_adv_tx_context_desc *context_desc;
+ u16 i = tx_ring->next_to_use;
+ u32 mss_l4len_idx = 0;
+ u32 type_tucmd = 0;
+
+ context_desc = IGC_TX_CTXTDESC(tx_ring, i);
+
+ i++;
+ tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
+
+ /* set bits to identify this as an advanced context descriptor */
+ type_tucmd |= IGC_TXD_CMD_DEXT | IGC_ADVTXD_DTYP_CTXT;
+
+ /* For i225, context index must be unique per ring. */
+ if (test_bit(IGC_RING_FLAG_TX_CTX_IDX, &tx_ring->flags))
+ mss_l4len_idx |= tx_ring->reg_idx << 4;
+
+ context_desc->vlan_macip_lens = 0;
+ context_desc->type_tucmd_mlhl = cpu_to_le32(type_tucmd);
+ context_desc->mss_l4len_idx = cpu_to_le32(mss_l4len_idx);
+
+ context_desc->launch_time = igc_tx_launchtime(adapter,
+ txtime);
+}
+
static void igc_xdp_xmit_zc(struct igc_ring *ring)
{
struct xsk_buff_pool *pool = ring->xsk_pool;
@@ -2599,11 +2628,25 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring)
budget = igc_desc_unused(ring);
- while (xsk_tx_peek_desc(pool, &xdp_desc) && budget--) {
+ while (xsk_tx_peek_desc(pool, &xdp_desc) && budget > 2) {
u32 cmd_type, olinfo_status;
struct igc_tx_buffer *bi;
+ s64 launch_tm = 0;
dma_addr_t dma;
+ bi = &ring->tx_buffer_info[ring->next_to_use];
+
+ if (ring->launchtime_enable && (xdp_desc.options & XDP_DESC_OPTION_SO_TXTIME)) {
+ launch_tm = xsk_buff_get_txtime(pool, &xdp_desc);
+ if (launch_tm != -1) {
+ budget--;
+ igc_launchtm_ctxtdesc(ring, (ktime_t)launch_tm);
+ }
+ }
+
+ /* re-read ntu as igc_launchtm_ctxtdesc() updates it */
+ ntu = ring->next_to_use;
+
cmd_type = IGC_ADVTXD_DTYP_DATA | IGC_ADVTXD_DCMD_DEXT |
IGC_ADVTXD_DCMD_IFCS | IGC_TXD_DCMD |
xdp_desc.len;
@@ -2612,12 +2655,12 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring)
dma = xsk_buff_raw_get_dma(pool, xdp_desc.addr);
xsk_buff_raw_dma_sync_for_device(pool, dma, xdp_desc.len);
+ budget--;
tx_desc = IGC_TX_DESC(ring, ntu);
tx_desc->read.cmd_type_len = cpu_to_le32(cmd_type);
tx_desc->read.olinfo_status = cpu_to_le32(olinfo_status);
tx_desc->read.buffer_addr = cpu_to_le64(dma);
- bi = &ring->tx_buffer_info[ntu];
bi->type = IGC_TX_BUFFER_TYPE_XSK;
bi->protocol = 0;
bi->bytecount = xdp_desc.len;
@@ -2630,9 +2673,9 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring)
ntu++;
if (ntu == ring->count)
ntu = 0;
+ ring->next_to_use = ntu;
}
- ring->next_to_use = ntu;
if (tx_desc) {
igc_flush_tx_descriptors(ring);
xsk_tx_release(pool);
--
2.24.3 (Apple Git-128)
