net/mlx5: Make the command interface cache more flexible

Add more cache command size sets and more entries for each set based on
the current commands set different sizes and commands frequency.

Fixes: e126ba97dba9 ('mlx5: Add driver for Mellanox Connect-IB adapters')
Signed-off-by: Mohamad Haj Yahia <mohamad@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx5/core/cmd.c

@@ -53,14 +53,6 @@ enum {
 	CMD_MODE_EVENTS
 };
 
-enum {
-	NUM_LONG_LISTS	  = 2,
-	NUM_MED_LISTS	  = 64,
-	LONG_LIST_SIZE	  = (2ULL * 1024 * 1024 * 1024 / PAGE_SIZE) * 8 + 16 +
-				MLX5_CMD_DATA_BLOCK_SIZE,
-	MED_LIST_SIZE	  = 16 + MLX5_CMD_DATA_BLOCK_SIZE,
-};
-
 enum {
 	MLX5_CMD_DELIVERY_STAT_OK			= 0x0,
 	MLX5_CMD_DELIVERY_STAT_SIGNAT_ERR		= 0x1,
@@ -1372,10 +1364,10 @@ static void free_msg(struct mlx5_core_dev *dev, struct mlx5_cmd_msg *msg)
 {
 	unsigned long flags;
 
-	if (msg->cache) {
-		spin_lock_irqsave(&msg->cache->lock, flags);
-		list_add_tail(&msg->list, &msg->cache->head);
-		spin_unlock_irqrestore(&msg->cache->lock, flags);
+	if (msg->parent) {
+		spin_lock_irqsave(&msg->parent->lock, flags);
+		list_add_tail(&msg->list, &msg->parent->head);
+		spin_unlock_irqrestore(&msg->parent->lock, flags);
 	} else {
 		mlx5_free_cmd_msg(dev, msg);
 	}
@@ -1472,30 +1464,37 @@ static struct mlx5_cmd_msg *alloc_msg(struct mlx5_core_dev *dev, int in_size,
 				      gfp_t gfp)
 {
 	struct mlx5_cmd_msg *msg = ERR_PTR(-ENOMEM);
+	struct cmd_msg_cache *ch = NULL;
 	struct mlx5_cmd *cmd = &dev->cmd;
-	struct cache_ent *ent = NULL;
-
-	if (in_size > MED_LIST_SIZE && in_size <= LONG_LIST_SIZE)
-		ent = &cmd->cache.large;
-	else if (in_size > 16 && in_size <= MED_LIST_SIZE)
-		ent = &cmd->cache.med;
-
-	if (ent) {
-		spin_lock_irq(&ent->lock);
-		if (!list_empty(&ent->head)) {
-			msg = list_entry(ent->head.next, typeof(*msg), list);
-			/* For cached lists, we must explicitly state what is
-			 * the real size
-			 */
-			msg->len = in_size;
-			list_del(&msg->list);
+	int i;
+
+	if (in_size <= 16)
+		goto cache_miss;
+
+	for (i = 0; i < MLX5_NUM_COMMAND_CACHES; i++) {
+		ch = &cmd->cache[i];
+		if (in_size > ch->max_inbox_size)
+			continue;
+		spin_lock_irq(&ch->lock);
+		if (list_empty(&ch->head)) {
+			spin_unlock_irq(&ch->lock);
+			continue;
 		}
-		spin_unlock_irq(&ent->lock);
+		msg = list_entry(ch->head.next, typeof(*msg), list);
+		/* For cached lists, we must explicitly state what is
+		 * the real size
+		 */
+		msg->len = in_size;
+		list_del(&msg->list);
+		spin_unlock_irq(&ch->lock);
+		break;
 	}
 
-	if (IS_ERR(msg))
-		msg = mlx5_alloc_cmd_msg(dev, gfp, in_size, 0);
+	if (!IS_ERR(msg))
+		return msg;
 
+cache_miss:
+	msg = mlx5_alloc_cmd_msg(dev, gfp, in_size, 0);
 	return msg;
 }
 
@@ -1593,58 +1592,56 @@ EXPORT_SYMBOL(mlx5_cmd_exec_cb);
 
 static void destroy_msg_cache(struct mlx5_core_dev *dev)
 {
-	struct mlx5_cmd *cmd = &dev->cmd;
+	struct cmd_msg_cache *ch;
 	struct mlx5_cmd_msg *msg;
 	struct mlx5_cmd_msg *n;
+	int i;
 
-	list_for_each_entry_safe(msg, n, &cmd->cache.large.head, list) {
-		list_del(&msg->list);
-		mlx5_free_cmd_msg(dev, msg);
-	}
-
-	list_for_each_entry_safe(msg, n, &cmd->cache.med.head, list) {
-		list_del(&msg->list);
-		mlx5_free_cmd_msg(dev, msg);
+	for (i = 0; i < MLX5_NUM_COMMAND_CACHES; i++) {
+		ch = &dev->cmd.cache[i];
+		list_for_each_entry_safe(msg, n, &ch->head, list) {
+			list_del(&msg->list);
+			mlx5_free_cmd_msg(dev, msg);
+		}
 	}
 }
 
-static int create_msg_cache(struct mlx5_core_dev *dev)
+static unsigned cmd_cache_num_ent[MLX5_NUM_COMMAND_CACHES] = {
+	512, 32, 16, 8, 2
+};
+
+static unsigned cmd_cache_ent_size[MLX5_NUM_COMMAND_CACHES] = {
+	16 + MLX5_CMD_DATA_BLOCK_SIZE,
+	16 + MLX5_CMD_DATA_BLOCK_SIZE * 2,
+	16 + MLX5_CMD_DATA_BLOCK_SIZE * 16,
+	16 + MLX5_CMD_DATA_BLOCK_SIZE * 256,
+	16 + MLX5_CMD_DATA_BLOCK_SIZE * 512,
+};
+
+static void create_msg_cache(struct mlx5_core_dev *dev)
 {
 	struct mlx5_cmd *cmd = &dev->cmd;
+	struct cmd_msg_cache *ch;
 	struct mlx5_cmd_msg *msg;
-	int err;
 	int i;
-
-	spin_lock_init(&cmd->cache.large.lock);
-	INIT_LIST_HEAD(&cmd->cache.large.head);
-	spin_lock_init(&cmd->cache.med.lock);
-	INIT_LIST_HEAD(&cmd->cache.med.head);
-
-	for (i = 0; i < NUM_LONG_LISTS; i++) {
-		msg = mlx5_alloc_cmd_msg(dev, GFP_KERNEL, LONG_LIST_SIZE, 0);
-		if (IS_ERR(msg)) {
-			err = PTR_ERR(msg);
-			goto ex_err;
-		}
-		msg->cache = &cmd->cache.large;
-		list_add_tail(&msg->list, &cmd->cache.large.head);
-	}
-
-	for (i = 0; i < NUM_MED_LISTS; i++) {
-		msg = mlx5_alloc_cmd_msg(dev, GFP_KERNEL, MED_LIST_SIZE, 0);
-		if (IS_ERR(msg)) {
-			err = PTR_ERR(msg);
-			goto ex_err;
+	int k;
+
+	/* Initialize and fill the caches with initial entries */
+	for (k = 0; k < MLX5_NUM_COMMAND_CACHES; k++) {
+		ch = &cmd->cache[k];
+		spin_lock_init(&ch->lock);
+		INIT_LIST_HEAD(&ch->head);
+		ch->num_ent = cmd_cache_num_ent[k];
+		ch->max_inbox_size = cmd_cache_ent_size[k];
+		for (i = 0; i < ch->num_ent; i++) {
+			msg = mlx5_alloc_cmd_msg(dev, GFP_KERNEL | __GFP_NOWARN,
+						 ch->max_inbox_size, 0);
+			if (IS_ERR(msg))
+				break;
+			msg->parent = ch;
+			list_add_tail(&msg->list, &ch->head);
 		}
-		msg->cache = &cmd->cache.med;
-		list_add_tail(&msg->list, &cmd->cache.med.head);
 	}
-
-	return 0;
-
-ex_err:
-	destroy_msg_cache(dev);
-	return err;
 }
 
 static int alloc_cmd_page(struct mlx5_core_dev *dev, struct mlx5_cmd *cmd)
@@ -1767,11 +1764,7 @@ int mlx5_cmd_init(struct mlx5_core_dev *dev)
 
 	cmd->mode = CMD_MODE_POLLING;
 
-	err = create_msg_cache(dev);
-	if (err) {
-		dev_err(&dev->pdev->dev, "failed to create command cache\n");
-		goto err_free_page;
-	}
+	create_msg_cache(dev);
 
 	set_wqname(dev);
 	cmd->wq = create_singlethread_workqueue(cmd->wq_name);

include/linux/mlx5/driver.h

@@ -208,7 +208,7 @@ struct mlx5_cmd_first {
 
 struct mlx5_cmd_msg {
 	struct list_head		list;
-	struct cache_ent	       *cache;
+	struct cmd_msg_cache	       *parent;
 	u32				len;
 	struct mlx5_cmd_first		first;
 	struct mlx5_cmd_mailbox	       *next;
@@ -228,17 +228,17 @@ struct mlx5_cmd_debug {
 	u16			outlen;
 };
 
-struct cache_ent {
+struct cmd_msg_cache {
 	/* protect block chain allocations
 	 */
 	spinlock_t		lock;
 	struct list_head	head;
+	unsigned int		max_inbox_size;
+	unsigned int		num_ent;
 };
 
-struct cmd_msg_cache {
-	struct cache_ent	large;
-	struct cache_ent	med;
-
+enum {
+	MLX5_NUM_COMMAND_CACHES = 5,
 };
 
 struct mlx5_cmd_stats {
@@ -281,7 +281,7 @@ struct mlx5_cmd {
 	struct mlx5_cmd_work_ent *ent_arr[MLX5_MAX_COMMANDS];
 	struct pci_pool *pool;
 	struct mlx5_cmd_debug dbg;
-	struct cmd_msg_cache cache;
+	struct cmd_msg_cache cache[MLX5_NUM_COMMAND_CACHES];
 	int checksum_disabled;
 	struct mlx5_cmd_stats stats[MLX5_CMD_OP_MAX];
 };