[PATCH net-next 6/9] mlx4: reduce rx ring page_cache size

[Eric Dumazet]

We only need to store the page and dma address.

Signed-off-by: Eric Dumazet <eduma...@google.com>
---
 drivers/net/ethernet/mellanox/mlx4/en_rx.c   | 17 ++++++++++-------
 drivers/net/ethernet/mellanox/mlx4/en_tx.c   |  2 --
 drivers/net/ethernet/mellanox/mlx4/mlx4_en.h |  6 +++++-
 3 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c 
b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 
80bb3c15f7c169f7091eb4a8dc06804f98b6..6c95694f6390aa9fbc5f941a97e305815949 
100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -250,7 +250,10 @@ static int mlx4_en_prepare_rx_desc(struct mlx4_en_priv 
*priv,
                                        (index << priv->log_rx_info);
 
        if (ring->page_cache.index > 0) {
-               frags[0] = ring->page_cache.buf[--ring->page_cache.index];
+               ring->page_cache.index--;
+               frags[0].page = 
ring->page_cache.buf[ring->page_cache.index].page;
+               frags[0].dma  = 
ring->page_cache.buf[ring->page_cache.index].dma;
+               frags[0].page_offset = XDP_PACKET_HEADROOM;
                rx_desc->data[0].addr = cpu_to_be64(frags[0].dma +
                                                    frags[0].page_offset);
                return 0;
@@ -534,7 +537,9 @@ bool mlx4_en_rx_recycle(struct mlx4_en_rx_ring *ring,
        if (cache->index >= MLX4_EN_CACHE_SIZE)
                return false;
 
-       cache->buf[cache->index++] = *frame;
+       cache->buf[cache->index].page = frame->page;
+       cache->buf[cache->index].dma = frame->dma;
+       cache->index++;
        return true;
 }
 
@@ -564,11 +569,9 @@ void mlx4_en_deactivate_rx_ring(struct mlx4_en_priv *priv,
        int i;
 
        for (i = 0; i < ring->page_cache.index; i++) {
-               struct mlx4_en_rx_alloc *frame = &ring->page_cache.buf[i];
-
-               dma_unmap_page(priv->ddev, frame->dma, frame->page_size,
-                              priv->dma_dir);
-               put_page(frame->page);
+               dma_unmap_page(priv->ddev, ring->page_cache.buf[i].dma,
+                              PAGE_SIZE, priv->dma_dir);
+               put_page(ring->page_cache.buf[i].page);
        }
        ring->page_cache.index = 0;
        mlx4_en_free_rx_buf(priv, ring);
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c 
b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
index 
98bc67a7249b14f8857fe1fd6baa40ae3ec5..e0c5ffb3e3a6607456e1f191b0b8c8becfc7 
100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -354,8 +354,6 @@ u32 mlx4_en_recycle_tx_desc(struct mlx4_en_priv *priv,
        struct mlx4_en_rx_alloc frame = {
                .page = tx_info->page,
                .dma = tx_info->map0_dma,
-               .page_offset = XDP_PACKET_HEADROOM,
-               .page_size = PAGE_SIZE,
        };
 
        if (!mlx4_en_rx_recycle(ring->recycle_ring, &frame)) {
diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h 
b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
index 
5d65a60e93b7a2ae84312cd0f2d474a065d9..c9916b75b94bc9364b2cbe6da06a5ea385c6 
100644
--- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
+++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
@@ -267,9 +267,13 @@ struct mlx4_en_rx_alloc {
 };
 
 #define MLX4_EN_CACHE_SIZE (2 * NAPI_POLL_WEIGHT)
+
 struct mlx4_en_page_cache {
        u32 index;
-       struct mlx4_en_rx_alloc buf[MLX4_EN_CACHE_SIZE];
+       struct {
+               struct page     *page;
+               dma_addr_t      dma;
+       } buf[MLX4_EN_CACHE_SIZE];
 };
 
 struct mlx4_en_priv;
-- 
2.11.0.483.g087da7b7c-goog