Re: [PATCH] net/af_xdp: parse numa node id from sysfs

[Ferruh Yigit <ferruh.yigit@amd.com>]

On 12/12/2022 12:48 AM, Frank Du wrote:
> Get from /sys/class/net/{if}/device/numa_node.
> 
> Signed-off-by: Frank Du <frank.du@intel.com>
> ---
>  drivers/net/af_xdp/rte_eth_af_xdp.c | 17 ++++++++++++++---
>  1 file changed, 14 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/af_xdp/rte_eth_af_xdp.c b/drivers/net/af_xdp/rte_eth_af_xdp.c
> index b6ec9bf490..38b9d36ab5 100644
> --- a/drivers/net/af_xdp/rte_eth_af_xdp.c
> +++ b/drivers/net/af_xdp/rte_eth_af_xdp.c
> @@ -39,6 +39,7 @@
>  #include <rte_power_intrinsics.h>
>  
>  #include "compat.h"
> +#include "eal_filesystem.h"
>  
>  #ifndef SO_PREFER_BUSY_POLL
>  #define SO_PREFER_BUSY_POLL 69
> @@ -2038,9 +2039,6 @@ rte_pmd_af_xdp_probe(struct rte_vdev_device *dev)
>  		return -EINVAL;
>  	}
>  
> -	if (dev->device.numa_node == SOCKET_ID_ANY)
> -		dev->device.numa_node = rte_socket_id();
> -
>  	if (parse_parameters(kvlist, if_name, &xsk_start_queue_idx,
>  			     &xsk_queue_cnt, &shared_umem, prog_path,
>  			     &busy_budget, &force_copy) < 0) {
> @@ -2053,6 +2051,19 @@ rte_pmd_af_xdp_probe(struct rte_vdev_device *dev)
>  		return -EINVAL;
>  	}
>  
> +	/* get numa node id from net sysfs */
> +	if (dev->device.numa_node == SOCKET_ID_ANY) {
> +		unsigned long numa = 0;
> +		char numa_path[PATH_MAX];
> +
> +		snprintf(numa_path, sizeof(numa_path), "/sys/class/net/%s/device/numa_node",
> +			 if_name);
> +		if (eal_parse_sysfs_value(numa_path, &numa) != 0)
> +			dev->device.numa_node = rte_socket_id();
> +		else
> +			dev->device.numa_node = numa;
> +	}
> +
>  	busy_budget = busy_budget == -1 ? ETH_AF_XDP_DFLT_BUSY_BUDGET :
>  					busy_budget;
>  

Hi Frank,

It looks reasonable to set virtual DPDK af_xdp device socket to actual
underlying device socket. And as I checked quickly, it works as expected.

But what is the impact and motivation of the patch? In other words why
you are doing this patch and what output you are expecting as a result?
Did you able to do any performance testing, and are you observing any
difference before and after this test?


Thanks,
ferruh