Commit 66adaf10 authored by Tim Hostetler's avatar Tim Hostetler Committed by Paolo Abeni
Browse files

gve: Prepare bpf_xdp_metadata_rx_timestamp support 



Support populating XDP RX metadata with hardware RX timestamps. This
patch utilizes the same underlying logic to calculate hardware
timestamps as the regular RX path.

xdp_metadata_ops is registered with the net_device in a future patch.

gve_rx_calculate_hwtstamp was pulled out so as to not duplicate logic
between gve_xdp_rx_timestamp and gve_rx_hwtstamp.

Signed-off-by: default avatarTim Hostetler <thostet@google.com>
Reviewed-by: default avatarWillem de Bruijn <willemb@google.com>
Reviewed-by: default avatarHarshitha Ramamurthy <hramamurthy@google.com>
Signed-off-by: default avatarJoshua Washington <joshwash@google.com>
Link: https://patch.msgid.link/20251114211146.292068-4-joshwash@google.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent f356a66b

drivers/net/ethernet/google/gve/gve.h

+2 −0
Original line number Diff line number Diff line
@@ -208,6 +208,8 @@ struct gve_rx_buf_state_dqo { 
/* Wrapper for XDP Rx metadata */

struct gve_xdp_buff {

	struct xdp_buff xdp;

	struct gve_priv *gve;

	const struct gve_rx_compl_desc_dqo *compl_desc;

};



/* `head` and `tail` are indices into an array, or -1 if empty. */

drivers/net/ethernet/google/gve/gve_dqo.h

+1 −0
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ netdev_tx_t gve_tx_dqo(struct sk_buff *skb, struct net_device *dev); 
netdev_features_t gve_features_check_dqo(struct sk_buff *skb,

					 struct net_device *dev,

					 netdev_features_t features);

int gve_xdp_rx_timestamp(const struct xdp_md *_ctx, u64 *timestamp);

bool gve_tx_poll_dqo(struct gve_notify_block *block, bool do_clean);

bool gve_xdp_poll_dqo(struct gve_notify_block *block);

bool gve_xsk_tx_poll_dqo(struct gve_notify_block *block, int budget);

drivers/net/ethernet/google/gve/gve_rx_dqo.c

+31 −10
Original line number Diff line number Diff line
@@ -456,20 +456,38 @@ static void gve_rx_skb_hash(struct sk_buff *skb, 
 * Note that this means if the time delta between packet reception and the last

 * clock read is greater than ~2 seconds, this will provide invalid results.

 */

static ktime_t gve_rx_get_hwtstamp(struct gve_priv *gve, u32 hwts)

{

	u64 last_read = READ_ONCE(gve->last_sync_nic_counter);

	u32 low = (u32)last_read;

	s32 diff = hwts - low;



	return ns_to_ktime(last_read + diff);

}



static void gve_rx_skb_hwtstamp(struct gve_rx_ring *rx,

				const struct gve_rx_compl_desc_dqo *desc)

{

	u64 last_read = READ_ONCE(rx->gve->last_sync_nic_counter);

	struct sk_buff *skb = rx->ctx.skb_head;

	u32 ts, low;

	s32 diff;



	if (desc->ts_sub_nsecs_low & GVE_DQO_RX_HWTSTAMP_VALID) {

		ts = le32_to_cpu(desc->ts);

		low = (u32)last_read;

		diff = ts - low;

		skb_hwtstamps(skb)->hwtstamp = ns_to_ktime(last_read + diff);

	if (desc->ts_sub_nsecs_low & GVE_DQO_RX_HWTSTAMP_VALID)

		skb_hwtstamps(skb)->hwtstamp =

			gve_rx_get_hwtstamp(rx->gve, le32_to_cpu(desc->ts));

}



int gve_xdp_rx_timestamp(const struct xdp_md *_ctx, u64 *timestamp)

{

	const struct gve_xdp_buff *ctx = (void *)_ctx;



	if (!ctx->gve->nic_ts_report)

		return -ENODATA;



	if (!(ctx->compl_desc->ts_sub_nsecs_low & GVE_DQO_RX_HWTSTAMP_VALID))

		return -ENODATA;



	*timestamp = gve_rx_get_hwtstamp(ctx->gve,

					 le32_to_cpu(ctx->compl_desc->ts));

	return 0;

}



static void gve_rx_free_skb(struct napi_struct *napi, struct gve_rx_ring *rx)
@@ -851,6 +869,9 @@ static int gve_rx_dqo(struct napi_struct *napi, struct gve_rx_ring *rx, 
				 buf_state->page_info.page_offset,

				 buf_state->page_info.pad,

				 buf_len, false);

		gve_xdp.gve = priv;

		gve_xdp.compl_desc = compl_desc;



		old_data = gve_xdp.xdp.data;

		xdp_act = bpf_prog_run_xdp(xprog, &gve_xdp.xdp);

		buf_state->page_info.pad += gve_xdp.xdp.data - old_data;