Subject: Re: [PATCH 09/10 net-next] net/mlx5: Add page_pool stats to the Mellanox driver

From: Jesper Dangaard Brouer <[email-masked]>
Date: Thu, 17 Oct 2019 13:09:35 +0200

On Wed, 16 Oct 2019 15:50:27 -0700
Jonathan Lemon <[email-masked]> wrote:

> Replace the now deprecated inernal cache stats with the page pool stats.

I can see that the stats you introduced are useful, but they have to be
implemented in way that does not hurt performance.

> # ethtool -S eth0 | grep rx_pool
>      rx_pool_cache_hit: 1646798
>      rx_pool_cache_full: 0
>      rx_pool_cache_empty: 15723566
>      rx_pool_ring_produce: 474958
>      rx_pool_ring_consume: 0
>      rx_pool_ring_return: 474958
>      rx_pool_flush: 144
>      rx_pool_node_change: 0
> 
> Showing about a 10% hit rate for the page pool.

What is the workload from above stats?

> Signed-off-by: Jonathan Lemon <[email-masked]>
> ---
>  drivers/net/ethernet/mellanox/mlx5/core/en.h  |  1 +
>  .../net/ethernet/mellanox/mlx5/core/en_main.c |  1 +
>  .../ethernet/mellanox/mlx5/core/en_stats.c    | 39 ++++++++++++-------
>  .../ethernet/mellanox/mlx5/core/en_stats.h    | 19 +++++----
>  4 files changed, 35 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
> index 2e281c755b65..b34519061d12 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
> @@ -50,6 +50,7 @@
>  #include <net/xdp.h>
>  #include <linux/dim.h>
>  #include <linux/bits.h>
> +#include <net/page_pool.h>
>  #include "wq.h"
>  #include "mlx5_core.h"
>  #include "en_stats.h"
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> index 2b828de1adf0..f10b5838fb17 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> @@ -551,6 +551,7 @@ static int mlx5e_alloc_rq(struct mlx5e_channel *c,
>  		pp_params.nid       = cpu_to_node(c->cpu);
>  		pp_params.dev       = c->pdev;
>  		pp_params.dma_dir   = rq->buff.map_dir;
> +		pp_params.stats     = &rq->stats->pool;
>  
>  		/* page_pool can be used even when there is no rq->xdp_prog,
>  		 * given page_pool does not handle DMA mapping there is no
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.c b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.c
> index ac6fdcda7019..ad42d965d786 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.c
> @@ -102,11 +102,14 @@ static const struct counter_desc sw_stats_desc[] = {
>  	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_buff_alloc_err) },
>  	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cqe_compress_blks) },
>  	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cqe_compress_pkts) },
> -	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cache_reuse) },
> -	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cache_full) },
> -	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cache_empty) },
> -	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cache_busy) },
> -	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cache_waive) },
> +	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_pool_cache_hit) },
> +	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_pool_cache_full) },
> +	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_pool_cache_empty) },
> +	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_pool_ring_produce) },
> +	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_pool_ring_consume) },
> +	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_pool_ring_return) },
> +	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_pool_flush) },
> +	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_pool_node_change) },
>  	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_congst_umr) },
>  	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_arfs_err) },
>  	{ MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_recover) },
> @@ -214,11 +217,14 @@ static void mlx5e_grp_sw_update_stats(struct mlx5e_priv *priv)
>  		s->rx_buff_alloc_err += rq_stats->buff_alloc_err;
>  		s->rx_cqe_compress_blks += rq_stats->cqe_compress_blks;
>  		s->rx_cqe_compress_pkts += rq_stats->cqe_compress_pkts;
> -		s->rx_cache_reuse += rq_stats->cache_reuse;
> -		s->rx_cache_full  += rq_stats->cache_full;
> -		s->rx_cache_empty += rq_stats->cache_empty;
> -		s->rx_cache_busy  += rq_stats->cache_busy;
> -		s->rx_cache_waive += rq_stats->cache_waive;
> +		s->rx_pool_cache_hit += rq_stats->pool.cache_hit;
> +		s->rx_pool_cache_full += rq_stats->pool.cache_full;
> +		s->rx_pool_cache_empty += rq_stats->pool.cache_empty;
> +		s->rx_pool_ring_produce += rq_stats->pool.ring_produce;
> +		s->rx_pool_ring_consume += rq_stats->pool.ring_consume;
> +		s->rx_pool_ring_return += rq_stats->pool.ring_return;
> +		s->rx_pool_flush += rq_stats->pool.flush;
> +		s->rx_pool_node_change += rq_stats->pool.node_change;
>  		s->rx_congst_umr  += rq_stats->congst_umr;
>  		s->rx_arfs_err    += rq_stats->arfs_err;
>  		s->rx_recover     += rq_stats->recover;
> @@ -1446,11 +1452,14 @@ static const struct counter_desc rq_stats_desc[] = {
>  	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, buff_alloc_err) },
>  	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cqe_compress_blks) },
>  	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cqe_compress_pkts) },
> -	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cache_reuse) },
> -	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cache_full) },
> -	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cache_empty) },
> -	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cache_busy) },
> -	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cache_waive) },
> +	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, pool.cache_hit) },
> +	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, pool.cache_full) },
> +	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, pool.cache_empty) },
> +	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, pool.ring_produce) },
> +	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, pool.ring_consume) },
> +	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, pool.ring_return) },
> +	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, pool.flush) },
> +	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, pool.node_change) },
>  	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, congst_umr) },
>  	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, arfs_err) },
>  	{ MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, recover) },
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h
> index 79f261bf86ac..7d6001969400 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h
> @@ -109,11 +109,14 @@ struct mlx5e_sw_stats {
>  	u64 rx_buff_alloc_err;
>  	u64 rx_cqe_compress_blks;
>  	u64 rx_cqe_compress_pkts;
> -	u64 rx_cache_reuse;
> -	u64 rx_cache_full;
> -	u64 rx_cache_empty;
> -	u64 rx_cache_busy;
> -	u64 rx_cache_waive;
> +	u64 rx_pool_cache_hit;
> +	u64 rx_pool_cache_full;
> +	u64 rx_pool_cache_empty;
> +	u64 rx_pool_ring_produce;
> +	u64 rx_pool_ring_consume;
> +	u64 rx_pool_ring_return;
> +	u64 rx_pool_flush;
> +	u64 rx_pool_node_change;
>  	u64 rx_congst_umr;
>  	u64 rx_arfs_err;
>  	u64 rx_recover;
> @@ -245,14 +248,10 @@ struct mlx5e_rq_stats {
>  	u64 buff_alloc_err;
>  	u64 cqe_compress_blks;
>  	u64 cqe_compress_pkts;
> -	u64 cache_reuse;
> -	u64 cache_full;
> -	u64 cache_empty;
> -	u64 cache_busy;
> -	u64 cache_waive;
>  	u64 congst_umr;
>  	u64 arfs_err;
>  	u64 recover;
> +	struct page_pool_stats pool;
>  };
>  
>  struct mlx5e_sq_stats {

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer