[PATCH net-next V2 3/3] net/mlx5: add debugfs stats for doorbell dma pools

From: Nimrod Oren <[email protected]>

Add a debugfs file exposing per-node DMA pool usage for doorbell
allocations.

  # cat /sys/kernel/debug/mlx5/<dev>/db_dma_pools
  node  block_size  used_blocks  allocated_blocks
     0          64            0                 0
     1          64            0                 0

Signed-off-by: Nimrod Oren <[email protected]>
Signed-off-by: Tariq Toukan <[email protected]>
---
 .../net/ethernet/mellanox/mlx5/core/alloc.c   | 27 +++++++++++++++++++
 include/linux/mlx5/driver.h                   |  1 +
 2 files changed, 28 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/alloc.c b/drivers/net/ethernet/mellanox/mlx5/core/alloc.c
index 3975c726d35c..a92cf545bdaf 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/alloc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/alloc.c
@@ -437,11 +437,34 @@ void mlx5_frag_buf_free(struct mlx5_core_dev *dev, struct mlx5_frag_buf *buf)
 }
 EXPORT_SYMBOL_GPL(mlx5_frag_buf_free);
 
+static int mlx5_db_dma_pools_debugfs_show(struct seq_file *file, void *priv)
+{
+	struct mlx5_core_dev *dev = file->private;
+	int node;
+
+	mlx5_dma_pools_debugfs_print_header(file);
+
+	for_each_node_state(node, N_POSSIBLE) {
+		struct mlx5_dma_pool *pool = dev->priv.db_node_pools[node];
+
+		if (!pool)
+			continue;
+
+		mlx5_dma_pool_debugfs_stats_print(file, pool);
+	}
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(mlx5_db_dma_pools_debugfs);
+
 void mlx5_db_pools_cleanup(struct mlx5_core_dev *dev)
 {
 	struct mlx5_priv *priv = &dev->priv;
 	int node;
 
+	debugfs_remove(priv->dbg.db_dma_pools_debugfs);
+	priv->dbg.db_dma_pools_debugfs = NULL;
+
 	for_each_node_state(node, N_POSSIBLE)
 		if (priv->db_node_pools[node])
 			mlx5_dma_pool_destroy(priv->db_node_pools[node]);
@@ -471,6 +494,10 @@ int mlx5_db_pools_init(struct mlx5_core_dev *dev)
 		priv->db_node_pools[node] = pool;
 	}
 
+	priv->dbg.db_dma_pools_debugfs =
+		debugfs_create_file("db_dma_pools", 0444, priv->dbg.dbg_root,
+				    dev, &mlx5_db_dma_pools_debugfs_fops);
+
 	return 0;
 }
 
diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index 2c56bb1d676d..83d0a83bbfbc 100644
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -548,6 +548,7 @@ struct mlx5_debugfs_entries {
 	struct dentry *cq_debugfs;
 	struct dentry *cmdif_debugfs;
 	struct dentry *frag_buf_dma_pools_debugfs;
+	struct dentry *db_dma_pools_debugfs;
 	struct dentry *pages_debugfs;
 	struct dentry *lag_debugfs;
 };
-- 
2.44.0