mlx4: Changing interrupt scheme

Adding a pool of MSI-X vectors and EQs that can be used explicitly by mlx4_core
customers (mlx4_ib, mlx4_en). The consumers will assign their own names to the
interrupt vectors. Those vectors are not opened at mlx4 device initialization,
opened by demand.
Changed the max number of possible EQs according to the new scheme, no longer relies on
on number of cores.
The new functionality is exposed through mlx4_assign_eq() and mlx4_release_eq().
Customers that do not use the new API will get completion vectors as before.

Signed-off-by: Markuze Alex <markuze@mellanox.co.il>
Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 101 insertions, 6 deletions

diff --git a/drivers/net/mlx4/eq.c b/drivers/net/mlx4/eq.c
index 552d0fce6f67..506cfd0372ec 100644
--- a/drivers/net/mlx4/eq.c
+++ b/drivers/net/mlx4/eq.c
@@ -42,7 +42,7 @@
 #include "fw.h"
 
 enum {
-	MLX4_IRQNAME_SIZE	= 64
+	MLX4_IRQNAME_SIZE	= 32
 };
 
 enum {
@@ -317,8 +317,8 @@ static int mlx4_num_eq_uar(struct mlx4_dev *dev)
 	 * we need to map, take the difference of highest index and
 	 * the lowest index we'll use and add 1.
 	 */
-	return (dev->caps.num_comp_vectors + 1 + dev->caps.reserved_eqs) / 4 -
-		dev->caps.reserved_eqs / 4 + 1;
+	return (dev->caps.num_comp_vectors + 1 + dev->caps.reserved_eqs +
+		 dev->caps.comp_pool)/4 - dev->caps.reserved_eqs/4 + 1;
 }
 
 static void __iomem *mlx4_get_eq_uar(struct mlx4_dev *dev, struct mlx4_eq *eq)
@@ -496,16 +496,32 @@ static void mlx4_free_eq(struct mlx4_dev *dev,
 static void mlx4_free_irqs(struct mlx4_dev *dev)
 {
 	struct mlx4_eq_table *eq_table = &mlx4_priv(dev)->eq_table;
-	int i;
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	int	i, vec;
 
 	if (eq_table->have_irq)
 		free_irq(dev->pdev->irq, dev);
+
 	for (i = 0; i < dev->caps.num_comp_vectors + 1; ++i)
 		if (eq_table->eq[i].have_irq) {
 			free_irq(eq_table->eq[i].irq, eq_table->eq + i);
 			eq_table->eq[i].have_irq = 0;
 		}
 
+	for (i = 0; i < dev->caps.comp_pool; i++) {
+		/*
+		 * Freeing the assigned irq's
+		 * all bits should be 0, but we need to validate
+		 */
+		if (priv->msix_ctl.pool_bm & 1ULL << i) {
+			/* NO need protecting*/
+			vec = dev->caps.num_comp_vectors + 1 + i;
+			free_irq(priv->eq_table.eq[vec].irq,
+				 &priv->eq_table.eq[vec]);
+		}
+	}
+
+
 	kfree(eq_table->irq_names);
 }
 
@@ -578,7 +594,8 @@ int mlx4_init_eq_table(struct mlx4_dev *dev)
 		(priv->eq_table.inta_pin < 32 ? 4 : 0);
 
 	priv->eq_table.irq_names =
-		kmalloc(MLX4_IRQNAME_SIZE * (dev->caps.num_comp_vectors + 1),
+		kmalloc(MLX4_IRQNAME_SIZE * (dev->caps.num_comp_vectors + 1 +
+					     dev->caps.comp_pool),
 			GFP_KERNEL);
 	if (!priv->eq_table.irq_names) {
 		err = -ENOMEM;
@@ -601,6 +618,22 @@ int mlx4_init_eq_table(struct mlx4_dev *dev)
 	if (err)
 		goto err_out_comp;
 
+	/*if additional completion vectors poolsize is 0 this loop will not run*/
+	for (i = dev->caps.num_comp_vectors + 1;
+	      i < dev->caps.num_comp_vectors + dev->caps.comp_pool + 1; ++i) {
+
+		err = mlx4_create_eq(dev, dev->caps.num_cqs -
+					  dev->caps.reserved_cqs +
+					  MLX4_NUM_SPARE_EQE,
+				     (dev->flags & MLX4_FLAG_MSI_X) ? i : 0,
+				     &priv->eq_table.eq[i]);
+		if (err) {
+			--i;
+			goto err_out_unmap;
+		}
+	}
+
+
 	if (dev->flags & MLX4_FLAG_MSI_X) {
 		const char *eq_name;
 
@@ -686,7 +719,7 @@ void mlx4_cleanup_eq_table(struct mlx4_dev *dev)
 
 	mlx4_free_irqs(dev);
 
-	for (i = 0; i < dev->caps.num_comp_vectors + 1; ++i)
+	for (i = 0; i < dev->caps.num_comp_vectors + dev->caps.comp_pool + 1; ++i)
 		mlx4_free_eq(dev, &priv->eq_table.eq[i]);
 
 	mlx4_unmap_clr_int(dev);
@@ -743,3 +776,65 @@ int mlx4_test_interrupts(struct mlx4_dev *dev)
 	return err;
 }
 EXPORT_SYMBOL(mlx4_test_interrupts);
+
+int mlx4_assign_eq(struct mlx4_dev *dev, char* name, int * vector)
+{
+
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	int vec = 0, err = 0, i;
+
+	spin_lock(&priv->msix_ctl.pool_lock);
+	for (i = 0; !vec && i < dev->caps.comp_pool; i++) {
+		if (~priv->msix_ctl.pool_bm & 1ULL << i) {
+			priv->msix_ctl.pool_bm |= 1ULL << i;
+			vec = dev->caps.num_comp_vectors + 1 + i;
+			snprintf(priv->eq_table.irq_names +
+					vec * MLX4_IRQNAME_SIZE,
+					MLX4_IRQNAME_SIZE, "%s", name);
+			err = request_irq(priv->eq_table.eq[vec].irq,
+					  mlx4_msi_x_interrupt, 0,
+					  &priv->eq_table.irq_names[vec<<5],
+					  priv->eq_table.eq + vec);
+			if (err) {
+				/*zero out bit by fliping it*/
+				priv->msix_ctl.pool_bm ^= 1 << i;
+				vec = 0;
+				continue;
+				/*we dont want to break here*/
+			}
+			eq_set_ci(&priv->eq_table.eq[vec], 1);
+		}
+	}
+	spin_unlock(&priv->msix_ctl.pool_lock);
+
+	if (vec) {
+		*vector = vec;
+	} else {
+		*vector = 0;
+		err = (i == dev->caps.comp_pool) ? -ENOSPC : err;
+	}
+	return err;
+}
+EXPORT_SYMBOL(mlx4_assign_eq);
+
+void mlx4_release_eq(struct mlx4_dev *dev, int vec)
+{
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	/*bm index*/
+	int i = vec - dev->caps.num_comp_vectors - 1;
+
+	if (likely(i >= 0)) {
+		/*sanity check , making sure were not trying to free irq's
+		  Belonging to a legacy EQ*/
+		spin_lock(&priv->msix_ctl.pool_lock);
+		if (priv->msix_ctl.pool_bm & 1ULL << i) {
+			free_irq(priv->eq_table.eq[vec].irq,
+				 &priv->eq_table.eq[vec]);
+			priv->msix_ctl.pool_bm &= ~(1ULL << i);
+		}
+		spin_unlock(&priv->msix_ctl.pool_lock);
+	}
+
+}
+EXPORT_SYMBOL(mlx4_release_eq);
+