i40e: Move q_vectors from pointer to array to array of pointers

Allocate the q_vectors individually. The advantage to this is that it
allows for easier freeing and allocation.  In addition it makes it so
that we could do node specific allocations at some point in the future.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Author: Alexander Duyck

drivers/net/ethernet/intel/i40e/i40e.h

@@ -366,7 +366,7 @@ struct i40e_vsi {
 	u8  dtype;
 
 	/* List of q_vectors allocated to this VSI */
-	struct i40e_q_vector *q_vectors;
+	struct i40e_q_vector **q_vectors;
 	int num_q_vectors;
 	int base_vector;
 
@@ -422,8 +422,9 @@ struct i40e_q_vector {
 
 	u8 num_ringpairs;	/* total number of ring pairs in vector */
 
-	char name[IFNAMSIZ + 9];
 	cpumask_t affinity_mask;
+	struct rcu_head rcu;	/* to avoid race with update stats on free */
+	char name[IFNAMSIZ + 9];
 } ____cacheline_internodealigned_in_smp;
 
 /* lan device */

drivers/net/ethernet/intel/i40e/i40e_debugfs.c

@@ -586,15 +586,6 @@ static void i40e_dbg_dump_vsi_seid(struct i40e_pf *pf, int seid)
 	dev_info(&pf->pdev->dev,
 		 "    max_frame = %d, rx_hdr_len = %d, rx_buf_len = %d dtype = %d\n",
 		 vsi->max_frame, vsi->rx_hdr_len, vsi->rx_buf_len, vsi->dtype);
-	if (vsi->q_vectors) {
-		for (i = 0; i < vsi->num_q_vectors; i++) {
-			dev_info(&pf->pdev->dev,
-				 "    q_vectors[%i]: base index = %ld\n",
-				 i, ((long int)*vsi->q_vectors[i].rx.ring-
-					(long int)*vsi->q_vectors[0].rx.ring)/
-					sizeof(struct i40e_ring));
-		}
-	}
 	dev_info(&pf->pdev->dev,
 		 "    num_q_vectors = %i, base_vector = %i\n",
 		 vsi->num_q_vectors, vsi->base_vector);
@@ -1995,7 +1986,7 @@ static ssize_t i40e_dbg_netdev_ops_write(struct file *filp,
 			goto netdev_ops_write_done;
 		}
 		for (i = 0; i < vsi->num_q_vectors; i++)
-			napi_schedule(&vsi->q_vectors[i].napi);
+			napi_schedule(&vsi->q_vectors[i]->napi);
 		dev_info(&pf->pdev->dev, "napi called\n");
 	} else {
 		dev_info(&pf->pdev->dev, "unknown command '%s'\n",

drivers/net/ethernet/intel/i40e/i40e_ethtool.c

@@ -906,8 +906,8 @@ static int i40e_set_coalesce(struct net_device *netdev,
 	}
 
 	vector = vsi->base_vector;
-	q_vector = vsi->q_vectors;
-	for (i = 0; i < vsi->num_q_vectors; i++, vector++, q_vector++) {
+	for (i = 0; i < vsi->num_q_vectors; i++, vector++) {
+		q_vector = vsi->q_vectors[i];
 		q_vector->rx.itr = ITR_TO_REG(vsi->rx_itr_setting);
 		wr32(hw, I40E_PFINT_ITRN(0, vector - 1), q_vector->rx.itr);
 		q_vector->tx.itr = ITR_TO_REG(vsi->tx_itr_setting);

drivers/net/ethernet/intel/i40e/i40e_main.c

@@ -2358,8 +2358,8 @@ static void i40e_vsi_configure_msix(struct i40e_vsi *vsi)
 	 */
 	qp = vsi->base_queue;
 	vector = vsi->base_vector;
-	q_vector = vsi->q_vectors;
-	for (i = 0; i < vsi->num_q_vectors; i++, q_vector++, vector++) {
+	for (i = 0; i < vsi->num_q_vectors; i++, vector++) {
+		q_vector = vsi->q_vectors[i];
 		q_vector->rx.itr = ITR_TO_REG(vsi->rx_itr_setting);
 		q_vector->rx.latency_range = I40E_LOW_LATENCY;
 		wr32(hw, I40E_PFINT_ITRN(I40E_RX_ITR, vector - 1),
@@ -2439,7 +2439,7 @@ static void i40e_enable_misc_int_causes(struct i40e_hw *hw)
  **/
 static void i40e_configure_msi_and_legacy(struct i40e_vsi *vsi)
 {
-	struct i40e_q_vector *q_vector = vsi->q_vectors;
+	struct i40e_q_vector *q_vector = vsi->q_vectors[0];
 	struct i40e_pf *pf = vsi->back;
 	struct i40e_hw *hw = &pf->hw;
 	u32 val;
@@ -2558,7 +2558,7 @@ static int i40e_vsi_request_irq_msix(struct i40e_vsi *vsi, char *basename)
 	int vector, err;
 
 	for (vector = 0; vector < q_vectors; vector++) {
-		struct i40e_q_vector *q_vector = &(vsi->q_vectors[vector]);
+		struct i40e_q_vector *q_vector = vsi->q_vectors[vector];
 
 		if (q_vector->tx.ring[0] && q_vector->rx.ring[0]) {
 			snprintf(q_vector->name, sizeof(q_vector->name) - 1,
@@ -2709,7 +2709,7 @@ static irqreturn_t i40e_intr(int irq, void *data)
 		i40e_flush(hw);
 
 		if (!test_bit(__I40E_DOWN, &pf->state))
-			napi_schedule(&pf->vsi[pf->lan_vsi]->q_vectors[0].napi);
+			napi_schedule(&pf->vsi[pf->lan_vsi]->q_vectors[0]->napi);
 	}
 
 	if (icr0 & I40E_PFINT_ICR0_ADMINQ_MASK) {
@@ -2785,7 +2785,7 @@ static irqreturn_t i40e_intr(int irq, void *data)
  **/
 static void map_vector_to_rxq(struct i40e_vsi *vsi, int v_idx, int r_idx)
 {
-	struct i40e_q_vector *q_vector = &(vsi->q_vectors[v_idx]);
+	struct i40e_q_vector *q_vector = vsi->q_vectors[v_idx];
 	struct i40e_ring *rx_ring = &(vsi->rx_rings[r_idx]);
 
 	rx_ring->q_vector = q_vector;
@@ -2803,7 +2803,7 @@ static void map_vector_to_rxq(struct i40e_vsi *vsi, int v_idx, int r_idx)
  **/
 static void map_vector_to_txq(struct i40e_vsi *vsi, int v_idx, int t_idx)
 {
-	struct i40e_q_vector *q_vector = &(vsi->q_vectors[v_idx]);
+	struct i40e_q_vector *q_vector = vsi->q_vectors[v_idx];
 	struct i40e_ring *tx_ring = &(vsi->tx_rings[t_idx]);
 
 	tx_ring->q_vector = q_vector;
@@ -2891,7 +2891,7 @@ static void i40e_netpoll(struct net_device *netdev)
 	pf->flags |= I40E_FLAG_IN_NETPOLL;
 	if (pf->flags & I40E_FLAG_MSIX_ENABLED) {
 		for (i = 0; i < vsi->num_q_vectors; i++)
-			i40e_msix_clean_rings(0, &vsi->q_vectors[i]);
+			i40e_msix_clean_rings(0, vsi->q_vectors[i]);
 	} else {
 		i40e_intr(pf->pdev->irq, netdev);
 	}
@@ -3077,14 +3077,14 @@ static void i40e_vsi_free_irq(struct i40e_vsi *vsi)
 			u16 vector = i + base;
 
 			/* free only the irqs that were actually requested */
-			if (vsi->q_vectors[i].num_ringpairs == 0)
+			if (vsi->q_vectors[i]->num_ringpairs == 0)
 				continue;
 
 			/* clear the affinity_mask in the IRQ descriptor */
 			irq_set_affinity_hint(pf->msix_entries[vector].vector,
 					      NULL);
 			free_irq(pf->msix_entries[vector].vector,
-				 &vsi->q_vectors[i]);
+				 vsi->q_vectors[i]);
 
 			/* Tear down the interrupt queue link list
 			 *
@@ -3167,6 +3167,38 @@ static void i40e_vsi_free_irq(struct i40e_vsi *vsi)
 	}
 }
 
+/**
+ * i40e_free_q_vector - Free memory allocated for specific interrupt vector
+ * @vsi: the VSI being configured
+ * @v_idx: Index of vector to be freed
+ *
+ * This function frees the memory allocated to the q_vector.  In addition if
+ * NAPI is enabled it will delete any references to the NAPI struct prior
+ * to freeing the q_vector.
+ **/
+static void i40e_free_q_vector(struct i40e_vsi *vsi, int v_idx)
+{
+	struct i40e_q_vector *q_vector = vsi->q_vectors[v_idx];
+	int r_idx;
+
+	if (!q_vector)
+		return;
+
+	/* disassociate q_vector from rings */
+	for (r_idx = 0; r_idx < q_vector->tx.count; r_idx++)
+		q_vector->tx.ring[r_idx]->q_vector = NULL;
+	for (r_idx = 0; r_idx < q_vector->rx.count; r_idx++)
+		q_vector->rx.ring[r_idx]->q_vector = NULL;
+
+	/* only VSI w/ an associated netdev is set up w/ NAPI */
+	if (vsi->netdev)
+		netif_napi_del(&q_vector->napi);
+
+	vsi->q_vectors[v_idx] = NULL;
+
+	kfree_rcu(q_vector, rcu);
+}
+
 /**
  * i40e_vsi_free_q_vectors - Free memory allocated for interrupt vectors
  * @vsi: the VSI being un-configured
@@ -3178,24 +3210,8 @@ static void i40e_vsi_free_q_vectors(struct i40e_vsi *vsi)
 {
 	int v_idx;
 
-	for (v_idx = 0; v_idx < vsi->num_q_vectors; v_idx++) {
-		struct i40e_q_vector *q_vector = &vsi->q_vectors[v_idx];
-		int r_idx;
-
-		if (!q_vector)
-			continue;
-
-		/* disassociate q_vector from rings */
-		for (r_idx = 0; r_idx < q_vector->tx.count; r_idx++)
-			q_vector->tx.ring[r_idx]->q_vector = NULL;
-		for (r_idx = 0; r_idx < q_vector->rx.count; r_idx++)
-			q_vector->rx.ring[r_idx]->q_vector = NULL;
-
-		/* only VSI w/ an associated netdev is set up w/ NAPI */
-		if (vsi->netdev)
-			netif_napi_del(&q_vector->napi);
-	}
-	kfree(vsi->q_vectors);
+	for (v_idx = 0; v_idx < vsi->num_q_vectors; v_idx++)
+		i40e_free_q_vector(vsi, v_idx);
 }
 
 /**
@@ -3245,7 +3261,7 @@ static void i40e_napi_enable_all(struct i40e_vsi *vsi)
 		return;
 
 	for (q_idx = 0; q_idx < vsi->num_q_vectors; q_idx++)
-		napi_enable(&vsi->q_vectors[q_idx].napi);
+		napi_enable(&vsi->q_vectors[q_idx]->napi);
 }
 
 /**
@@ -3260,7 +3276,7 @@ static void i40e_napi_disable_all(struct i40e_vsi *vsi)
 		return;
 
 	for (q_idx = 0; q_idx < vsi->num_q_vectors; q_idx++)
-		napi_disable(&vsi->q_vectors[q_idx].napi);
+		napi_disable(&vsi->q_vectors[q_idx]->napi);
 }
 
 /**
@@ -4945,6 +4961,7 @@ static int i40e_vsi_mem_alloc(struct i40e_pf *pf, enum i40e_vsi_type type)
 {
 	int ret = -ENODEV;
 	struct i40e_vsi *vsi;
+	int sz_vectors;
 	int vsi_idx;
 	int i;
 
@@ -4970,14 +4987,14 @@ static int i40e_vsi_mem_alloc(struct i40e_pf *pf, enum i40e_vsi_type type)
 		vsi_idx = i;             /* Found one! */
 	} else {
 		ret = -ENODEV;
-		goto err_alloc_vsi;  /* out of VSI slots! */
+		goto unlock_pf;  /* out of VSI slots! */
 	}
 	pf->next_vsi = ++i;
 
 	vsi = kzalloc(sizeof(*vsi), GFP_KERNEL);
 	if (!vsi) {
 		ret = -ENOMEM;
-		goto err_alloc_vsi;
+		goto unlock_pf;
 	}
 	vsi->type = type;
 	vsi->back = pf;
@@ -4992,12 +5009,25 @@ static int i40e_vsi_mem_alloc(struct i40e_pf *pf, enum i40e_vsi_type type)
 
 	i40e_set_num_rings_in_vsi(vsi);
 
+	/* allocate memory for q_vector pointers */
+	sz_vectors = sizeof(struct i40e_q_vectors *) * vsi->num_q_vectors;
+	vsi->q_vectors = kzalloc(sz_vectors, GFP_KERNEL);
+	if (!vsi->q_vectors) {
+		ret = -ENOMEM;
+		goto err_vectors;
+	}
+
 	/* Setup default MSIX irq handler for VSI */
 	i40e_vsi_setup_irqhandler(vsi, i40e_msix_clean_rings);
 
 	pf->vsi[vsi_idx] = vsi;
 	ret = vsi_idx;
-err_alloc_vsi:
+	goto unlock_pf;
+
+err_vectors:
+	pf->next_vsi = i - 1;
+	kfree(vsi);
+unlock_pf:
 	mutex_unlock(&pf->switch_mutex);
 	return ret;
 }
@@ -5038,6 +5068,9 @@ static int i40e_vsi_clear(struct i40e_vsi *vsi)
 	i40e_put_lump(pf->qp_pile, vsi->base_queue, vsi->idx);
 	i40e_put_lump(pf->irq_pile, vsi->base_vector, vsi->idx);
 
+	/* free the ring and vector containers */
+	kfree(vsi->q_vectors);
+
 	pf->vsi[vsi->idx] = NULL;
 	if (vsi->idx < pf->next_vsi)
 		pf->next_vsi = vsi->idx;
@@ -5256,6 +5289,35 @@ static int i40e_init_msix(struct i40e_pf *pf)
 	return err;
 }
 
+/**
+ * i40e_alloc_q_vector - Allocate memory for a single interrupt vector
+ * @vsi: the VSI being configured
+ * @v_idx: index of the vector in the vsi struct
+ *
+ * We allocate one q_vector.  If allocation fails we return -ENOMEM.
+ **/
+static int i40e_alloc_q_vector(struct i40e_vsi *vsi, int v_idx)
+{
+	struct i40e_q_vector *q_vector;
+
+	/* allocate q_vector */
+	q_vector = kzalloc(sizeof(struct i40e_q_vector), GFP_KERNEL);
+	if (!q_vector)
+		return -ENOMEM;
+
+	q_vector->vsi = vsi;
+	q_vector->v_idx = v_idx;
+	cpumask_set_cpu(v_idx, &q_vector->affinity_mask);
+	if (vsi->netdev)
+		netif_napi_add(vsi->netdev, &q_vector->napi,
+			       i40e_napi_poll, vsi->work_limit);
+
+	/* tie q_vector and vsi together */
+	vsi->q_vectors[v_idx] = q_vector;
+
+	return 0;
+}
+
 /**
  * i40e_alloc_q_vectors - Allocate memory for interrupt vectors
  * @vsi: the VSI being configured
@@ -5267,6 +5329,7 @@ static int i40e_alloc_q_vectors(struct i40e_vsi *vsi)
 {
 	struct i40e_pf *pf = vsi->back;
 	int v_idx, num_q_vectors;
+	int err;
 
 	/* if not MSIX, give the one vector only to the LAN VSI */
 	if (pf->flags & I40E_FLAG_MSIX_ENABLED)
@@ -5276,22 +5339,19 @@ static int i40e_alloc_q_vectors(struct i40e_vsi *vsi)
 	else
 		return -EINVAL;
 
-	vsi->q_vectors = kcalloc(num_q_vectors,
-				 sizeof(struct i40e_q_vector),
-				 GFP_KERNEL);
-	if (!vsi->q_vectors)
-		return -ENOMEM;
-
 	for (v_idx = 0; v_idx < num_q_vectors; v_idx++) {
-		vsi->q_vectors[v_idx].vsi = vsi;
-		vsi->q_vectors[v_idx].v_idx = v_idx;
-		cpumask_set_cpu(v_idx, &vsi->q_vectors[v_idx].affinity_mask);
-		if (vsi->netdev)
-			netif_napi_add(vsi->netdev, &vsi->q_vectors[v_idx].napi,
-				       i40e_napi_poll, vsi->work_limit);
+		err = i40e_alloc_q_vector(vsi, v_idx);
+		if (err)
+			goto err_out;
 	}
 
 	return 0;
+
+err_out:
+	while (v_idx--)
+		i40e_free_q_vector(vsi, v_idx);
+
+	return err;
 }
 
 /**
@@ -5958,7 +6018,7 @@ static int i40e_vsi_setup_vectors(struct i40e_vsi *vsi)
 	int ret = -ENOENT;
 	struct i40e_pf *pf = vsi->back;
 
-	if (vsi->q_vectors) {
+	if (vsi->q_vectors[0]) {
 		dev_info(&pf->pdev->dev, "VSI %d has existing q_vectors\n",
 			 vsi->seid);
 		return -EEXIST;