net/mlx5e: RX, Remove internal page_cache

This patch removes the internal rx page_cache and uses the generic
page_pool api only. It used to be that the page_pool couldn't handle all
the mlx5 driver usecases, but with the introduction of skb recycling and
page fragmentaton in the page_pool full switch can now be made. Some
benfits of this transition:
* Better page recycling in the cases when the page_cache was suffering
  from head of queue blocking. The page_pool doesn't have this issue.
* DMA mapping/unmapping can be managed by the page_pool.
* mlx5e_rq size reduced by more than 50% due to the page_cache array
  being deleted.

This patch only removes the page_cache. Downstream patches will enable
the required page_pool features and will add further fine-tuning.

Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

1 files changed, 0 insertions, 13 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 77f81d74ff30..b0322a20b71b 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -900,9 +900,6 @@ static int mlx5e_alloc_rq(struct mlx5e_params *params,
 		rq->dim.mode = DIM_CQ_PERIOD_MODE_START_FROM_EQE;
 	}
 
-	rq->page_cache.head = 0;
-	rq->page_cache.tail = 0;
-
 	return 0;
 
 err_destroy_page_pool:
@@ -933,7 +930,6 @@ err_rq_xdp_prog:
 static void mlx5e_free_rq(struct mlx5e_rq *rq)
 {
 	struct bpf_prog *old_prog;
-	int i;
 
 	if (xdp_rxq_info_is_reg(&rq->xdp_rxq)) {
 		old_prog = rcu_dereference_protected(rq->xdp_prog,
@@ -953,15 +949,6 @@ static void mlx5e_free_rq(struct mlx5e_rq *rq)
 		mlx5e_free_wqe_alloc_info(rq);
 	}
 
-	for (i = rq->page_cache.head; i != rq->page_cache.tail;
-	     i = (i + 1) & (MLX5E_CACHE_SIZE - 1)) {
-		/* With AF_XDP, page_cache is not used, so this loop is not
-		 * entered, and it's safe to call mlx5e_page_release_dynamic
-		 * directly.
-		 */
-		mlx5e_page_release_dynamic(rq, rq->page_cache.page_cache[i], false);
-	}
-
 	xdp_rxq_info_unreg(&rq->xdp_rxq);
 	page_pool_destroy(rq->page_pool);
 	mlx5_wq_destroy(&rq->wq_ctrl);