net: Add NAPI IRQ support

Add support to associate the interrupt vector number for a
NAPI instance.
Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Link: https://lore.kernel.org/r/170147334728.5260.13221803396905901904.stgit@anambiarhost.jf.intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/intel/ice/ice_lib.c

@@ -2978,6 +2978,8 @@ void ice_q_vector_set_napi_queues(struct ice_q_vector *q_vector, bool locked)
 		ice_queue_set_napi(q_vector->vsi->netdev, tx_ring->q_index,
 				   NETDEV_QUEUE_TYPE_TX, &q_vector->napi,
 				   locked);
+	/* Also set the interrupt number for the NAPI */
+	netif_napi_set_irq(&q_vector->napi, q_vector->irq.virq);
 }
 
 /**

include/linux/netdevice.h

@@ -382,6 +382,7 @@ struct napi_struct {
 	/* control-path-only fields follow */
 	struct list_head	dev_list;
 	struct hlist_node	napi_hash_node;
+	int			irq;
 };
 
 enum {
@@ -2665,6 +2666,11 @@ void netif_queue_set_napi(struct net_device *dev, unsigned int queue_index,
 			  enum netdev_queue_type type,
 			  struct napi_struct *napi);
 
+static inline void netif_napi_set_irq(struct napi_struct *napi, int irq)
+{
+	napi->irq = irq;
+}
+
 /* Default NAPI poll() weight
  * Device drivers are strongly advised to not use bigger value
  */

net/core/dev.c

@@ -6471,6 +6471,7 @@ void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi,
 	 */
 	if (dev->threaded && napi_kthread_create(napi))
 		dev->threaded = 0;
+	netif_napi_set_irq(napi, -1);
 }
 EXPORT_SYMBOL(netif_napi_add_weight);
 

net/core/netdev-genl.c

@@ -180,7 +180,11 @@ netdev_nl_napi_fill_one(struct sk_buff *rsp, struct napi_struct *napi,
 	if (nla_put_u32(rsp, NETDEV_A_NAPI_IFINDEX, napi->dev->ifindex))
 		goto nla_put_failure;
 
+	if (napi->irq >= 0 && nla_put_u32(rsp, NETDEV_A_NAPI_IRQ, napi->irq))
+		goto nla_put_failure;
+
 	genlmsg_end(rsp, hdr);
+
 	return 0;
 
 nla_put_failure: