Re: [PATCH 1/1] net: fec: add initial XDP support

From: Andrew Lunn
Date: Wed Sep 28 2022 - 21:51:31 EST


> +struct fec_enet_xdp_stats {
> + u64 xdp_pass;
> + u64 xdp_drop;
> + u64 xdp_xmit;
> + u64 xdp_redirect;
> + u64 xdp_xmit_err;
> + u64 xdp_tx;
> + u64 xdp_tx_err;
> +};
> +
> + switch (act) {
> + case XDP_PASS:
> + rxq->stats.xdp_pass++;

Since the stats are u64, and most machines using the FEC are 32 bit,
you cannot just do an increment. Took a look at u64_stats_sync.h.

> -#define FEC_STATS_SIZE (ARRAY_SIZE(fec_stats) * sizeof(u64))
> +static struct fec_xdp_stat {
> + char name[ETH_GSTRING_LEN];
> + u32 count;
> +} fec_xdp_stats[] = {
> + { "rx_xdp_redirect", 0 },
> + { "rx_xdp_pass", 0 },
> + { "rx_xdp_drop", 0 },
> + { "rx_xdp_tx", 0 },
> + { "rx_xdp_tx_errors", 0 },
> + { "tx_xdp_xmit", 0 },
> + { "tx_xdp_xmit_errors", 0 },
> +};
> +
> +#define FEC_STATS_SIZE ((ARRAY_SIZE(fec_stats) + \
> + ARRAY_SIZE(fec_xdp_stats)) * sizeof(u64))

The page pool also has some stats. See page_pool_get_stats(),
page_pool_ethtool_stats_get_strings() etc.

Andrew