On Wed, 19 Feb 2020 10:57:37 +0100
Lorenzo Bianconi <lorenzo@xxxxxxxxxx> wrote:
> Introduce "rx" prefix in the name scheme for xdp counters
> on rx path.
> Differentiate between XDP_TX and ndo_xdp_xmit counters
>
> Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
Acked-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx>
> ---
> Changes since RFC:
> - rename rx_xdp_tx_xmit in rx_xdp_tx
> - move tx stats accounting in mvneta_xdp_xmit_back/mvneta_xdp_xmit
I like how you managed to bulk update the ndo_xdp_xmit counters.
> ---
> drivers/net/ethernet/marvell/mvneta.c | 52 ++++++++++++++++++---------
> 1 file changed, 36 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
> index b7045b6a15c2..8e1feb678cea 100644
> --- a/drivers/net/ethernet/marvell/mvneta.c
> +++ b/drivers/net/ethernet/marvell/mvneta.c
> @@ -344,6 +344,7 @@ enum {
> ETHTOOL_XDP_REDIRECT,
> ETHTOOL_XDP_PASS,
> ETHTOOL_XDP_DROP,
> + ETHTOOL_XDP_XMIT,
> ETHTOOL_XDP_TX,
> ETHTOOL_MAX_STATS,
> };
> @@ -399,10 +400,11 @@ static const struct mvneta_statistic mvneta_statistics[] = {
> { ETHTOOL_STAT_EEE_WAKEUP, T_SW, "eee_wakeup_errors", },
> { ETHTOOL_STAT_SKB_ALLOC_ERR, T_SW, "skb_alloc_errors", },
> { ETHTOOL_STAT_REFILL_ERR, T_SW, "refill_errors", },
> - { ETHTOOL_XDP_REDIRECT, T_SW, "xdp_redirect", },
> - { ETHTOOL_XDP_PASS, T_SW, "xdp_pass", },
> - { ETHTOOL_XDP_DROP, T_SW, "xdp_drop", },
> - { ETHTOOL_XDP_TX, T_SW, "xdp_tx", },
> + { ETHTOOL_XDP_REDIRECT, T_SW, "rx_xdp_redirect", },
> + { ETHTOOL_XDP_PASS, T_SW, "rx_xdp_pass", },
> + { ETHTOOL_XDP_DROP, T_SW, "rx_xdp_drop", },
> + { ETHTOOL_XDP_TX, T_SW, "rx_xdp_tx", },
> + { ETHTOOL_XDP_XMIT, T_SW, "tx_xdp_xmit", },
> };
I'm fine with these names.
Based on the code, the "rx_xdp_tx" counter is counting the successful
XDP_TX operations, which I actually like. I could use this to debug,
if my XDP_TX operations are drop packets (due to TX-queue full), by
using fexit or XDP-prog counter to deduct this. I think it would be
valuable to provide a "rx_xdp_tx_err" counter, that would detect this,
it makes it easier to detect this for end-users (as a followup patch).
> struct mvneta_stats {
> @@ -414,6 +416,7 @@ struct mvneta_stats {
> u64 xdp_redirect;
> u64 xdp_pass;
> u64 xdp_drop;
> + u64 xdp_xmit;
> u64 xdp_tx;
> };
>
> @@ -2012,7 +2015,6 @@ static int
> mvneta_xdp_submit_frame(struct mvneta_port *pp, struct mvneta_tx_queue *txq,
> struct xdp_frame *xdpf, bool dma_map)
> {
> - struct mvneta_pcpu_stats *stats = this_cpu_ptr(pp->stats);
> struct mvneta_tx_desc *tx_desc;
> struct mvneta_tx_buf *buf;
> dma_addr_t dma_addr;
> @@ -2047,12 +2049,6 @@ mvneta_xdp_submit_frame(struct mvneta_port *pp, struct mvneta_tx_queue *txq,
> tx_desc->buf_phys_addr = dma_addr;
> tx_desc->data_size = xdpf->len;
>
> - u64_stats_update_begin(&stats->syncp);
> - stats->es.ps.tx_bytes += xdpf->len;
> - stats->es.ps.tx_packets++;
> - stats->es.ps.xdp_tx++;
> - u64_stats_update_end(&stats->syncp);
> -
> mvneta_txq_inc_put(txq);
> txq->pending++;
> txq->count++;
> @@ -2079,8 +2075,17 @@ mvneta_xdp_xmit_back(struct mvneta_port *pp, struct xdp_buff *xdp)
>
> __netif_tx_lock(nq, cpu);
> ret = mvneta_xdp_submit_frame(pp, txq, xdpf, false);
> - if (ret == MVNETA_XDP_TX)
> + if (ret == MVNETA_XDP_TX) {
> + struct mvneta_pcpu_stats *stats = this_cpu_ptr(pp->stats);
> +
> + u64_stats_update_begin(&stats->syncp);
> + stats->es.ps.tx_bytes += xdpf->len;
> + stats->es.ps.tx_packets++;
> + stats->es.ps.xdp_tx++;
> + u64_stats_update_end(&stats->syncp);
> +
> mvneta_txq_pend_desc_add(pp, txq, 0);
> + }
> __netif_tx_unlock(nq);
>
> return ret;
> @@ -2091,10 +2096,11 @@ mvneta_xdp_xmit(struct net_device *dev, int num_frame,
> struct xdp_frame **frames, u32 flags)
> {
> struct mvneta_port *pp = netdev_priv(dev);
> + struct mvneta_pcpu_stats *stats = this_cpu_ptr(pp->stats);
> + int i, nxmit_byte = 0, nxmit = num_frame;
> int cpu = smp_processor_id();
> struct mvneta_tx_queue *txq;
> struct netdev_queue *nq;
> - int i, drops = 0;
> u32 ret;
>
> if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
> @@ -2106,9 +2112,11 @@ mvneta_xdp_xmit(struct net_device *dev, int num_frame,
> __netif_tx_lock(nq, cpu);
> for (i = 0; i < num_frame; i++) {
> ret = mvneta_xdp_submit_frame(pp, txq, frames[i], true);
> - if (ret != MVNETA_XDP_TX) {
> + if (ret == MVNETA_XDP_TX) {
> + nxmit_byte += frames[i]->len;
> + } else {
> xdp_return_frame_rx_napi(frames[i]);
> - drops++;
> + nxmit--;
> }
> }
>
> @@ -2116,7 +2124,13 @@ mvneta_xdp_xmit(struct net_device *dev, int num_frame,
> mvneta_txq_pend_desc_add(pp, txq, 0);
> __netif_tx_unlock(nq);
>
> - return num_frame - drops;
> + u64_stats_update_begin(&stats->syncp);
> + stats->es.ps.tx_bytes += nxmit_byte;
> + stats->es.ps.tx_packets += nxmit;
> + stats->es.ps.xdp_xmit += nxmit;
> + u64_stats_update_end(&stats->syncp);
> +
> + return nxmit;
> }
Updating xmit counter per bulk, nice.
>
[...]
--
Best regards,
Jesper Dangaard Brouer
MSc.CS, Principal Kernel Engineer at Red Hat
LinkedIn: http://www.linkedin.com/in/brouer
