[PATCH v6 23/27] net/iavf: avoid rte malloc in irq map config

[Anatoly Burakov <anatoly.burakov@intel.com>]

Currently, when configuring IRQ maps, we are using rte_zmalloc followed
by an immediate rte_free. This memory does not need to be stored in
hugepage memory, so replace it with stack allocation.

The original code did not check maximum IRQ map size, because the design
was built around an anti-pattern of caller having to chunk the IRQ map
calls. This has now been corrected as well.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
 drivers/net/intel/iavf/iavf.h        |   3 +-
 drivers/net/intel/iavf/iavf_ethdev.c |  15 +---
 drivers/net/intel/iavf/iavf_vchnl.c  | 110 +++++++++++++++++----------
 3 files changed, 72 insertions(+), 56 deletions(-)

diff --git a/drivers/net/intel/iavf/iavf.h b/drivers/net/intel/iavf/iavf.h
index 77a2c94290..f9bb398a77 100644
--- a/drivers/net/intel/iavf/iavf.h
+++ b/drivers/net/intel/iavf/iavf.h
@@ -511,8 +511,7 @@ int iavf_add_del_vlan_v2(struct iavf_adapter *adapter, uint16_t vlanid,
 			 bool add);
 int iavf_get_vlan_offload_caps_v2(struct iavf_adapter *adapter);
 int iavf_config_irq_map(struct iavf_adapter *adapter);
-int iavf_config_irq_map_lv(struct iavf_adapter *adapter, uint16_t num,
-			uint16_t index);
+int iavf_config_irq_map_lv(struct iavf_adapter *adapter, uint16_t num);
 void iavf_add_del_all_mac_addr(struct iavf_adapter *adapter, bool add);
 int iavf_dev_link_update(struct rte_eth_dev *dev,
 			__rte_unused int wait_to_complete);
diff --git a/drivers/net/intel/iavf/iavf_ethdev.c b/drivers/net/intel/iavf/iavf_ethdev.c
index f7bfd099ed..89826547f0 100644
--- a/drivers/net/intel/iavf/iavf_ethdev.c
+++ b/drivers/net/intel/iavf/iavf_ethdev.c
@@ -919,20 +919,7 @@ static int iavf_config_rx_queues_irqs(struct rte_eth_dev *dev,
 			goto config_irq_map_err;
 		}
 	} else {
-		uint16_t num_qv_maps = dev->data->nb_rx_queues;
-		uint16_t index = 0;
-
-		while (num_qv_maps > IAVF_IRQ_MAP_NUM_PER_BUF) {
-			if (iavf_config_irq_map_lv(adapter,
-					IAVF_IRQ_MAP_NUM_PER_BUF, index)) {
-				PMD_DRV_LOG(ERR, "config interrupt mapping for large VF failed");
-				goto config_irq_map_err;
-			}
-			num_qv_maps -= IAVF_IRQ_MAP_NUM_PER_BUF;
-			index += IAVF_IRQ_MAP_NUM_PER_BUF;
-		}
-
-		if (iavf_config_irq_map_lv(adapter, num_qv_maps, index)) {
+		if (iavf_config_irq_map_lv(adapter, dev->data->nb_rx_queues)) {
 			PMD_DRV_LOG(ERR, "config interrupt mapping for large VF failed");
 			goto config_irq_map_err;
 		}
diff --git a/drivers/net/intel/iavf/iavf_vchnl.c b/drivers/net/intel/iavf/iavf_vchnl.c
index f0ab3b950b..baadb4b686 100644
--- a/drivers/net/intel/iavf/iavf_vchnl.c
+++ b/drivers/net/intel/iavf/iavf_vchnl.c
@@ -1314,81 +1314,111 @@ int
 iavf_config_irq_map(struct iavf_adapter *adapter)
 {
 	struct iavf_info *vf = IAVF_DEV_PRIVATE_TO_VF(adapter);
-	struct virtchnl_irq_map_info *map_info;
-	struct virtchnl_vector_map *vecmap;
-	struct iavf_cmd_info args;
-	int len, i, err;
+	struct {
+		struct virtchnl_irq_map_info map_info;
+		struct virtchnl_vector_map vecmap[IAVF_MAX_NUM_QUEUES_DFLT];
+	} map_req = {0};
+	struct virtchnl_irq_map_info *map_info = &map_req.map_info;
+	struct iavf_cmd_info args = {0};
+	int i, err, max_vmi = -1;
 
-	len = sizeof(struct virtchnl_irq_map_info) +
-	      sizeof(struct virtchnl_vector_map) * vf->nb_msix;
+	if (adapter->dev_data->nb_rx_queues > IAVF_MAX_NUM_QUEUES_DFLT) {
+		PMD_DRV_LOG(ERR, "number of queues (%u) exceeds the max supported (%u)",
+			    adapter->dev_data->nb_rx_queues, IAVF_MAX_NUM_QUEUES_DFLT);
+		return -EINVAL;
+	}
 
-	map_info = rte_zmalloc("map_info", len, 0);
-	if (!map_info)
-		return -ENOMEM;
-
-	map_info->num_vectors = vf->nb_msix;
 	for (i = 0; i < adapter->dev_data->nb_rx_queues; i++) {
-		vecmap =
-		    &map_info->vecmap[vf->qv_map[i].vector_id - vf->msix_base];
+		struct virtchnl_vector_map *vecmap;
+		/* always 0 for 1 MSIX, never bigger than rxq for multi MSIX */
+		uint16_t vmi = vf->qv_map[i].vector_id - vf->msix_base;
+
+		/* can't happen but avoid static analysis warnings */
+		if (vmi >= IAVF_MAX_NUM_QUEUES_DFLT) {
+			PMD_DRV_LOG(ERR, "vector id (%u) exceeds the max supported (%u)",
+					vf->qv_map[i].vector_id,
+					vf->msix_base + IAVF_MAX_NUM_QUEUES_DFLT - 1);
+			return -EINVAL;
+		}
+
+		vecmap = &map_info->vecmap[vmi];
 		vecmap->vsi_id = vf->vsi_res->vsi_id;
 		vecmap->rxitr_idx = IAVF_ITR_INDEX_DEFAULT;
 		vecmap->vector_id = vf->qv_map[i].vector_id;
 		vecmap->txq_map = 0;
 		vecmap->rxq_map |= 1 << vf->qv_map[i].queue_id;
+
+		/* MSIX vectors round robin so look for max */
+		if (vmi > max_vmi) {
+			map_info->num_vectors++;
+			max_vmi = vmi;
+		}
 	}
 
 	args.ops = VIRTCHNL_OP_CONFIG_IRQ_MAP;
 	args.in_args = (u8 *)map_info;
-	args.in_args_size = len;
+	args.in_args_size = sizeof(map_req);
 	args.out_buffer = vf->aq_resp;
 	args.out_size = IAVF_AQ_BUF_SZ;
 	err = iavf_execute_vf_cmd_safe(adapter, &args, 0);
 	if (err)
 		PMD_DRV_LOG(ERR, "fail to execute command OP_CONFIG_IRQ_MAP");
 
-	rte_free(map_info);
 	return err;
 }
 
-int
-iavf_config_irq_map_lv(struct iavf_adapter *adapter, uint16_t num,
-		uint16_t index)
+static int
+iavf_config_irq_map_lv_chunk(struct iavf_adapter *adapter, uint16_t chunk_sz, uint16_t chunk_start)
 {
+	struct {
+		struct virtchnl_queue_vector_maps map_info;
+		struct virtchnl_queue_vector qv_maps[IAVF_CFG_Q_NUM_PER_BUF];
+	} chunk_req = {0};
 	struct iavf_info *vf = IAVF_DEV_PRIVATE_TO_VF(adapter);
-	struct virtchnl_queue_vector_maps *map_info;
-	struct virtchnl_queue_vector *qv_maps;
-	struct iavf_cmd_info args;
-	int len, i, err;
-	int count = 0;
+	struct iavf_cmd_info args = {0};
+	struct virtchnl_queue_vector_maps *map_info = &chunk_req.map_info;
+	struct virtchnl_queue_vector *qv_maps = chunk_req.qv_maps;
+	uint16_t chunk_end = chunk_start + chunk_sz;
+	uint16_t i;
 
-	len = sizeof(struct virtchnl_queue_vector_maps) +
-	      sizeof(struct virtchnl_queue_vector) * (num - 1);
-
-	map_info = rte_zmalloc("map_info", len, 0);
-	if (!map_info)
-		return -ENOMEM;
+	if (chunk_sz > IAVF_CFG_Q_NUM_PER_BUF)
+		return -EINVAL;
 
 	map_info->vport_id = vf->vsi_res->vsi_id;
-	map_info->num_qv_maps = num;
-	for (i = index; i < index + map_info->num_qv_maps; i++) {
-		qv_maps = &map_info->qv_maps[count++];
+	map_info->num_qv_maps = chunk_sz;
+	for (i = chunk_start; i < chunk_end; i++) {
+		qv_maps = &map_info->qv_maps[i];
 		qv_maps->itr_idx = VIRTCHNL_ITR_IDX_0;
 		qv_maps->queue_type = VIRTCHNL_QUEUE_TYPE_RX;
-		qv_maps->queue_id = vf->qv_map[i].queue_id;
-		qv_maps->vector_id = vf->qv_map[i].vector_id;
+		qv_maps->queue_id = vf->qv_map[chunk_start + i].queue_id;
+		qv_maps->vector_id = vf->qv_map[chunk_start + i].vector_id;
 	}
 
 	args.ops = VIRTCHNL_OP_MAP_QUEUE_VECTOR;
 	args.in_args = (u8 *)map_info;
-	args.in_args_size = len;
+	args.in_args_size = sizeof(chunk_req);
 	args.out_buffer = vf->aq_resp;
 	args.out_size = IAVF_AQ_BUF_SZ;
-	err = iavf_execute_vf_cmd_safe(adapter, &args, 0);
-	if (err)
-		PMD_DRV_LOG(ERR, "fail to execute command OP_MAP_QUEUE_VECTOR");
 
-	rte_free(map_info);
-	return err;
+	return iavf_execute_vf_cmd_safe(adapter, &args, 0);
+}
+
+int
+iavf_config_irq_map_lv(struct iavf_adapter *adapter, uint16_t num)
+{
+	uint16_t c;
+	int err;
+
+	for (c = 0; c < num; c += IAVF_CFG_Q_NUM_PER_BUF) {
+		uint16_t chunk_sz = RTE_MIN(num - c, IAVF_CFG_Q_NUM_PER_BUF);
+		err = iavf_config_irq_map_lv_chunk(adapter, chunk_sz, c);
+		if (err) {
+			PMD_DRV_LOG(ERR, "Failed to configure irq map chunk [%u, %u)",
+					c, c + chunk_sz);
+			return err;
+		}
+	}
+	return 0;
 }
 
 void
-- 
2.47.3