Re: [PATCH net-next v1] idpf: export RX hardware timestamping information to XDP

[Alexander Lobakin <aleksander.lobakin@intel.com>]

From: Alexander Lobakin <aleksander.lobakin@intel.com>
Date: Wed, 17 Dec 2025 15:33:40 +0100

> From: Mina Almasry <almasrymina@google.com>
> Date: Sat, 22 Nov 2025 14:08:36 +0000
> 
>> From: YiFei Zhu <zhuyifei@google.com>
>>
>> The logic is similar to idpf_rx_hwtstamp, but the data is exported
>> as a BPF kfunc instead of appended to an skb.
>>
>> A idpf_queue_has(PTP, rxq) condition is added to check the queue
>> supports PTP similar to idpf_rx_process_skb_fields.
>>
>> Cc: intel-wired-lan@lists.osuosl.org
>>
>> Signed-off-by: YiFei Zhu <zhuyifei@google.com>
>> Signed-off-by: Mina Almasry <almasrymina@google.com>
>> ---
>>  drivers/net/ethernet/intel/idpf/xdp.c | 27 +++++++++++++++++++++++++++
>>  1 file changed, 27 insertions(+)
>>
>> diff --git a/drivers/net/ethernet/intel/idpf/xdp.c b/drivers/net/ethernet/intel/idpf/xdp.c
>> index 21ce25b0567f..850389ca66b6 100644
>> --- a/drivers/net/ethernet/intel/idpf/xdp.c
>> +++ b/drivers/net/ethernet/intel/idpf/xdp.c
>> @@ -2,6 +2,7 @@
>>  /* Copyright (C) 2025 Intel Corporation */
>>  
>>  #include "idpf.h"
>> +#include "idpf_ptp.h"
>>  #include "idpf_virtchnl.h"
>>  #include "xdp.h"
>>  #include "xsk.h"
>> @@ -369,6 +370,31 @@ int idpf_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
>>  				       idpf_xdp_tx_finalize);
>>  }
>>  
>> +static int idpf_xdpmo_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp)

Also please put this function *after* rx_hash() to...

>> +{
>> +	const struct virtchnl2_rx_flex_desc_adv_nic_3 *rx_desc;
> 
> Sorry I know it's a late comment...
> 
> Could you please you the optimized descriptor structure from idpf/xdp.h
> instead of the regular one? To be consistent with the Rx hash timestamp
> function and give more room for optimization.
> 
>> +	const struct libeth_xdp_buff *xdp = (typeof(xdp))ctx;
>> +	const struct idpf_rx_queue *rxq;
>> +	u64 cached_time, ts_ns;
>> +	u32 ts_high;
>> +
>> +	rx_desc = xdp->desc;
>> +	rxq = libeth_xdp_buff_to_rq(xdp, typeof(*rxq), xdp_rxq);
>> +
>> +	if (!idpf_queue_has(PTP, rxq))
>> +		return -ENODATA;
>> +	if (!(rx_desc->ts_low & VIRTCHNL2_RX_FLEX_TSTAMP_VALID))
>> +		return -ENODATA;
>> +
>> +	cached_time = READ_ONCE(rxq->cached_phc_time);
>> +
>> +	ts_high = le32_to_cpu(rx_desc->ts_high);
>> +	ts_ns = idpf_ptp_tstamp_extend_32b_to_64b(cached_time, ts_high);
>> +
>> +	*timestamp = ts_ns;
>> +	return 0;
>> +}
>> +
>>  static int idpf_xdpmo_rx_hash(const struct xdp_md *ctx, u32 *hash,
>>  			      enum xdp_rss_hash_type *rss_type)
>>  {
>> @@ -392,6 +418,7 @@ static int idpf_xdpmo_rx_hash(const struct xdp_md *ctx, u32 *hash,
>>  }
>>  
>>  static const struct xdp_metadata_ops idpf_xdpmo = {
>> +	.xmo_rx_timestamp	= idpf_xdpmo_rx_timestamp,
>>  	.xmo_rx_hash		= idpf_xdpmo_rx_hash,

...keep the alphabetic sorting here.

>>  };
>>  
>>
>> base-commit: e05021a829b834fecbd42b173e55382416571b2c

Thanks,
Olek