Merge branch 'net-napi-add-cpu-affinity-to-napi-config'

Ahmed Zaki says:

====================
net: napi: add CPU affinity to napi->config

Drivers usually need to re-apply the user-set IRQ affinity to their IRQs
after reset. However, since there can be only one IRQ affinity notifier
for each IRQ, registering IRQ notifiers conflicts with the ARFS rmap
management in the core (which also registers separate IRQ affinity
notifiers).

Move the IRQ affinity management to the napi struct. This way we can have
a unified IRQ notifier to re-apply the user-set affinity and also manage
the ARFS rmaps.

The first patch moves the aRFS rmap management to core. It also adds the
IRQ affinity mask to napi_config and re-applies the mask after reset.
Patches 2, 4 and 5 use the new API for ena, ice and idpf drivers.

ICE does not always delete the NAPIs before releasing the IRQs. The third
patch makes sure the driver removes the IRQ number along with the queue
when the NAPIs are disabled. Without this, the next patches in this series
would free the IRQ before releasing the IRQ notifier (which generates
warnings).

Tested on ice and idpf.

v8: https://lore.kernel.org/20250211210657.428439-1-ahmed.zaki@intel.com
v7: https://lore.kernel.org/20250204220622.156061-1-ahmed.zaki@intel.com
v6: https://lore.kernel.org/20250118003335.155379-1-ahmed.zaki@intel.com
v5: https://lore.kernel.org/20250113171042.158123-1-ahmed.zaki@intel.com
v4: https://lore.kernel.org/20250109233107.17519-1-ahmed.zaki@intel.com
v3: https://lore.kernel.org/20250104004314.208259-1-ahmed.zaki@intel.com
v2: https://lore.kernel.org/202412190454.nwvp3hU2-lkp@intel.com
v1: https://lore.kernel.org/20241210002626.366878-1-ahmed.zaki@intel.com
====================

Link: https://patch.msgid.link/20250224232228.990783-1-ahmed.zaki@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

19 files changed, 343 insertions, 163 deletions

diff --git a/Documentation/networking/scaling.rst b/Documentation/networking/scaling.rst
index 6984700cec6a..99b6a61e5e31 100644
--- a/Documentation/networking/scaling.rst
+++ b/Documentation/networking/scaling.rst
@@ -434,8 +434,10 @@ rps_dev_flow_table. The stack consults a CPU to hardware queue map which
 is maintained by the NIC driver. This is an auto-generated reverse map of
 the IRQ affinity table shown by /proc/interrupts. Drivers can use
 functions in the cpu_rmap (“CPU affinity reverse map”) kernel library
-to populate the map. For each CPU, the corresponding queue in the map is
-set to be one whose processing CPU is closest in cache locality.
+to populate the map. Alternatively, drivers can delegate the cpu_rmap
+management to the Kernel by calling netif_enable_cpu_rmap(). For each CPU,
+the corresponding queue in the map is set to be one whose processing CPU is
+closest in cache locality.
 
 
 Accelerated RFS Configuration
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c
index c1295dfad0d0..6aab85a7c60a 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -5,9 +5,6 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
-#ifdef CONFIG_RFS_ACCEL
-#include <linux/cpu_rmap.h>
-#endif /* CONFIG_RFS_ACCEL */
 #include <linux/ethtool.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -162,30 +159,6 @@ int ena_xmit_common(struct ena_adapter *adapter,
 	return 0;
 }
 
-static int ena_init_rx_cpu_rmap(struct ena_adapter *adapter)
-{
-#ifdef CONFIG_RFS_ACCEL
-	u32 i;
-	int rc;
-
-	adapter->netdev->rx_cpu_rmap = alloc_irq_cpu_rmap(adapter->num_io_queues);
-	if (!adapter->netdev->rx_cpu_rmap)
-		return -ENOMEM;
-	for (i = 0; i < adapter->num_io_queues; i++) {
-		int irq_idx = ENA_IO_IRQ_IDX(i);
-
-		rc = irq_cpu_rmap_add(adapter->netdev->rx_cpu_rmap,
-				      pci_irq_vector(adapter->pdev, irq_idx));
-		if (rc) {
-			free_irq_cpu_rmap(adapter->netdev->rx_cpu_rmap);
-			adapter->netdev->rx_cpu_rmap = NULL;
-			return rc;
-		}
-	}
-#endif /* CONFIG_RFS_ACCEL */
-	return 0;
-}
-
 static void ena_init_io_rings_common(struct ena_adapter *adapter,
 				     struct ena_ring *ring, u16 qid)
 {
@@ -1596,7 +1569,7 @@ static int ena_enable_msix(struct ena_adapter *adapter)
 		adapter->num_io_queues = irq_cnt - ENA_ADMIN_MSIX_VEC;
 	}
 
-	if (ena_init_rx_cpu_rmap(adapter))
+	if (netif_enable_cpu_rmap(adapter->netdev, adapter->num_io_queues))
 		netif_warn(adapter, probe, adapter->netdev,
 			   "Failed to map IRQs to CPUs\n");
 
@@ -1742,13 +1715,6 @@ static void ena_free_io_irq(struct ena_adapter *adapter)
 	struct ena_irq *irq;
 	int i;
 
-#ifdef CONFIG_RFS_ACCEL
-	if (adapter->msix_vecs >= 1) {
-		free_irq_cpu_rmap(adapter->netdev->rx_cpu_rmap);
-		adapter->netdev->rx_cpu_rmap = NULL;
-	}
-#endif /* CONFIG_RFS_ACCEL */
-
 	for (i = ENA_IO_IRQ_FIRST_IDX; i < ENA_MAX_MSIX_VEC(io_queue_count); i++) {
 		irq = &adapter->irq_tbl[i];
 		irq_set_affinity_hint(irq->vector, NULL);
@@ -4131,13 +4097,6 @@ static void __ena_shutoff(struct pci_dev *pdev, bool shutdown)
 	ena_dev = adapter->ena_dev;
 	netdev = adapter->netdev;
 
-#ifdef CONFIG_RFS_ACCEL
-	if ((adapter->msix_vecs >= 1) && (netdev->rx_cpu_rmap)) {
-		free_irq_cpu_rmap(netdev->rx_cpu_rmap);
-		netdev->rx_cpu_rmap = NULL;
-	}
-
-#endif /* CONFIG_RFS_ACCEL */
 	/* Make sure timer and reset routine won't be called after
 	 * freeing device resources.
 	 */
diff --git a/drivers/net/ethernet/intel/ice/ice.h b/drivers/net/ethernet/intel/ice/ice.h
index c9104b13e1d2..5ceeae664598 100644
--- a/drivers/net/ethernet/intel/ice/ice.h
+++ b/drivers/net/ethernet/intel/ice/ice.h
@@ -475,9 +475,6 @@ struct ice_q_vector {
 	struct ice_ring_container rx;
 	struct ice_ring_container tx;
 
-	cpumask_t affinity_mask;
-	struct irq_affinity_notify affinity_notify;
-
 	struct ice_channel *ch;
 
 	char name[ICE_INT_NAME_STR_LEN];
diff --git a/drivers/net/ethernet/intel/ice/ice_arfs.c b/drivers/net/ethernet/intel/ice/ice_arfs.c
index 7cee365cc7d1..171cdec741c2 100644
--- a/drivers/net/ethernet/intel/ice/ice_arfs.c
+++ b/drivers/net/ethernet/intel/ice/ice_arfs.c
@@ -571,25 +571,6 @@ void ice_clear_arfs(struct ice_vsi *vsi)
 }
 
 /**
- * ice_free_cpu_rx_rmap - free setup CPU reverse map
- * @vsi: the VSI to be forwarded to
- */
-void ice_free_cpu_rx_rmap(struct ice_vsi *vsi)
-{
-	struct net_device *netdev;
-
-	if (!vsi || vsi->type != ICE_VSI_PF)
-		return;
-
-	netdev = vsi->netdev;
-	if (!netdev || !netdev->rx_cpu_rmap)
-		return;
-
-	free_irq_cpu_rmap(netdev->rx_cpu_rmap);
-	netdev->rx_cpu_rmap = NULL;
-}
-
-/**
  * ice_set_cpu_rx_rmap - setup CPU reverse map for each queue
  * @vsi: the VSI to be forwarded to
  */
@@ -597,7 +578,6 @@ int ice_set_cpu_rx_rmap(struct ice_vsi *vsi)
 {
 	struct net_device *netdev;
 	struct ice_pf *pf;
-	int i;
 
 	if (!vsi || vsi->type != ICE_VSI_PF)
 		return 0;
@@ -610,18 +590,7 @@ int ice_set_cpu_rx_rmap(struct ice_vsi *vsi)
 	netdev_dbg(netdev, "Setup CPU RMAP: vsi type 0x%x, ifname %s, q_vectors %d\n",
 		   vsi->type, netdev->name, vsi->num_q_vectors);
 
-	netdev->rx_cpu_rmap = alloc_irq_cpu_rmap(vsi->num_q_vectors);
-	if (unlikely(!netdev->rx_cpu_rmap))
-		return -EINVAL;
-
-	ice_for_each_q_vector(vsi, i)
-		if (irq_cpu_rmap_add(netdev->rx_cpu_rmap,
-				     vsi->q_vectors[i]->irq.virq)) {
-			ice_free_cpu_rx_rmap(vsi);
-			return -EINVAL;
-		}
-
-	return 0;
+	return netif_enable_cpu_rmap(netdev, vsi->num_q_vectors);
 }
 
 /**
diff --git a/drivers/net/ethernet/intel/ice/ice_arfs.h b/drivers/net/ethernet/intel/ice/ice_arfs.h
index 9669ad9bf7b5..9706293128c3 100644
--- a/drivers/net/ethernet/intel/ice/ice_arfs.h
+++ b/drivers/net/ethernet/intel/ice/ice_arfs.h
@@ -45,7 +45,6 @@ int
 ice_rx_flow_steer(struct net_device *netdev, const struct sk_buff *skb,
 		  u16 rxq_idx, u32 flow_id);
 void ice_clear_arfs(struct ice_vsi *vsi);
-void ice_free_cpu_rx_rmap(struct ice_vsi *vsi);
 void ice_init_arfs(struct ice_vsi *vsi);
 void ice_sync_arfs_fltrs(struct ice_pf *pf);
 int ice_set_cpu_rx_rmap(struct ice_vsi *vsi);
@@ -56,7 +55,6 @@ ice_is_arfs_using_perfect_flow(struct ice_hw *hw,
 			       enum ice_fltr_ptype flow_type);
 #else
 static inline void ice_clear_arfs(struct ice_vsi *vsi) { }
-static inline void ice_free_cpu_rx_rmap(struct ice_vsi *vsi) { }
 static inline void ice_init_arfs(struct ice_vsi *vsi) { }
 static inline void ice_sync_arfs_fltrs(struct ice_pf *pf) { }
 static inline void ice_remove_arfs(struct ice_pf *pf) { }
diff --git a/drivers/net/ethernet/intel/ice/ice_base.c b/drivers/net/ethernet/intel/ice/ice_base.c
index b3234a55a253..6db4ad8fc70b 100644
--- a/drivers/net/ethernet/intel/ice/ice_base.c
+++ b/drivers/net/ethernet/intel/ice/ice_base.c
@@ -147,10 +147,6 @@ skip_alloc:
 	q_vector->reg_idx = q_vector->irq.index;
 	q_vector->vf_reg_idx = q_vector->irq.index;
 
-	/* only set affinity_mask if the CPU is online */
-	if (cpu_online(v_idx))
-		cpumask_set_cpu(v_idx, &q_vector->affinity_mask);
-
 	/* This will not be called in the driver load path because the netdev
 	 * will not be created yet. All other cases with register the NAPI
 	 * handler here (i.e. resume, reset/rebuild, etc.)
@@ -276,7 +272,8 @@ static void ice_cfg_xps_tx_ring(struct ice_tx_ring *ring)
 	if (test_and_set_bit(ICE_TX_XPS_INIT_DONE, ring->xps_state))
 		return;
 
-	netif_set_xps_queue(ring->netdev, &ring->q_vector->affinity_mask,
+	netif_set_xps_queue(ring->netdev,
+			    &ring->q_vector->napi.config->affinity_mask,
 			    ring->q_index);
 }
 
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c b/drivers/net/ethernet/intel/ice/ice_lib.c
index 7f5b229cab05..715efd8a359f 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_lib.c
@@ -2592,7 +2592,6 @@ void ice_vsi_free_irq(struct ice_vsi *vsi)
 		return;
 
 	vsi->irqs_ready = false;
-	ice_free_cpu_rx_rmap(vsi);
 
 	ice_for_each_q_vector(vsi, i) {
 		int irq_num;
@@ -2605,12 +2604,6 @@ void ice_vsi_free_irq(struct ice_vsi *vsi)
 		      vsi->q_vectors[i]->num_ring_rx))
 			continue;
 
-		/* clear the affinity notifier in the IRQ descriptor */
-		if (!IS_ENABLED(CONFIG_RFS_ACCEL))
-			irq_set_affinity_notifier(irq_num, NULL);
-
-		/* clear the affinity_hint in the IRQ descriptor */
-		irq_update_affinity_hint(irq_num, NULL);
 		synchronize_irq(irq_num);
 		devm_free_irq(ice_pf_to_dev(pf), irq_num, vsi->q_vectors[i]);
 	}
@@ -2765,11 +2758,18 @@ void ice_vsi_set_napi_queues(struct ice_vsi *vsi)
 void ice_vsi_clear_napi_queues(struct ice_vsi *vsi)
 {
 	struct net_device *netdev = vsi->netdev;
-	int q_idx;
+	int q_idx, v_idx;
 
 	if (!netdev)
 		return;
 
+	/* Clear the NAPI's interrupt number */
+	ice_for_each_q_vector(vsi, v_idx) {
+		struct ice_q_vector *q_vector = vsi->q_vectors[v_idx];
+
+		netif_napi_set_irq(&q_vector->napi, -1);
+	}
+
 	ice_for_each_txq(vsi, q_idx)
 		netif_queue_set_napi(netdev, q_idx, NETDEV_QUEUE_TYPE_TX, NULL);
 
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index b084839eb811..eff4afabeef6 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -2528,34 +2528,6 @@ int ice_schedule_reset(struct ice_pf *pf, enum ice_reset_req reset)
 }
 
 /**
- * ice_irq_affinity_notify - Callback for affinity changes
- * @notify: context as to what irq was changed
- * @mask: the new affinity mask
- *
- * This is a callback function used by the irq_set_affinity_notifier function
- * so that we may register to receive changes to the irq affinity masks.
- */
-static void
-ice_irq_affinity_notify(struct irq_affinity_notify *notify,
-			const cpumask_t *mask)
-{
-	struct ice_q_vector *q_vector =
-		container_of(notify, struct ice_q_vector, affinity_notify);
-
-	cpumask_copy(&q_vector->affinity_mask, mask);
-}
-
-/**
- * ice_irq_affinity_release - Callback for affinity notifier release
- * @ref: internal core kernel usage
- *
- * This is a callback function used by the irq_set_affinity_notifier function
- * to inform the current notification subscriber that they will no longer
- * receive notifications.
- */
-static void ice_irq_affinity_release(struct kref __always_unused *ref) {}
-
-/**
  * ice_vsi_ena_irq - Enable IRQ for the given VSI
  * @vsi: the VSI being configured
  */
@@ -2618,19 +2590,6 @@ static int ice_vsi_req_irq_msix(struct ice_vsi *vsi, char *basename)
 				   err);
 			goto free_q_irqs;
 		}
-
-		/* register for affinity change notifications */
-		if (!IS_ENABLED(CONFIG_RFS_ACCEL)) {
-			struct irq_affinity_notify *affinity_notify;
-
-			affinity_notify = &q_vector->affinity_notify;
-			affinity_notify->notify = ice_irq_affinity_notify;
-			affinity_notify->release = ice_irq_affinity_release;
-			irq_set_affinity_notifier(irq_num, affinity_notify);
-		}
-
-		/* assign the mask for this irq */
-		irq_update_affinity_hint(irq_num, &q_vector->affinity_mask);
 	}
 
 	err = ice_set_cpu_rx_rmap(vsi);
@@ -2646,9 +2605,6 @@ static int ice_vsi_req_irq_msix(struct ice_vsi *vsi, char *basename)
 free_q_irqs:
 	while (vector--) {
 		irq_num = vsi->q_vectors[vector]->irq.virq;
-		if (!IS_ENABLED(CONFIG_RFS_ACCEL))
-			irq_set_affinity_notifier(irq_num, NULL);
-		irq_update_affinity_hint(irq_num, NULL);
 		devm_free_irq(dev, irq_num, &vsi->q_vectors[vector]);
 	}
 	return err;
@@ -3675,6 +3631,9 @@ void ice_set_netdev_features(struct net_device *netdev)
 	 */
 	netdev->hw_features |= NETIF_F_RXFCS;
 
+	/* Allow core to manage IRQs affinity */
+	netif_set_affinity_auto(netdev);
+
 	netif_set_tso_max_size(netdev, ICE_MAX_TSO_SIZE);
 }
 
diff --git a/drivers/net/ethernet/intel/idpf/idpf_lib.c b/drivers/net/ethernet/intel/idpf/idpf_lib.c
index a3d6b8f198a8..f3aea7bcdaa3 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_lib.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_lib.c
@@ -814,6 +814,7 @@ static int idpf_cfg_netdev(struct idpf_vport *vport)
 	netdev->hw_features |= dflt_features | offloads;
 	netdev->hw_enc_features |= dflt_features | offloads;
 	idpf_set_ethtool_ops(netdev);
+	netif_set_affinity_auto(netdev);
 	SET_NETDEV_DEV(netdev, &adapter->pdev->dev);
 
 	/* carrier off on init to avoid Tx hangs */
diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
index 2747dc69999a..672dfad1fb21 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_txrx.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
@@ -3551,8 +3551,6 @@ void idpf_vport_intr_rel(struct idpf_vport *vport)
 		q_vector->tx = NULL;
 		kfree(q_vector->rx);
 		q_vector->rx = NULL;
-
-		free_cpumask_var(q_vector->affinity_mask);
 	}
 
 	kfree(vport->q_vectors);
@@ -3579,8 +3577,6 @@ static void idpf_vport_intr_rel_irq(struct idpf_vport *vport)
 		vidx = vport->q_vector_idxs[vector];
 		irq_num = adapter->msix_entries[vidx].vector;
 
-		/* clear the affinity_mask in the IRQ descriptor */
-		irq_set_affinity_hint(irq_num, NULL);
 		kfree(free_irq(irq_num, q_vector));
 	}
 }
@@ -3768,8 +3764,6 @@ static int idpf_vport_intr_req_irq(struct idpf_vport *vport)
 				   "Request_irq failed, error: %d\n", err);
 			goto free_q_irqs;
 		}
-		/* assign the mask for this irq */
-		irq_set_affinity_hint(irq_num, q_vector->affinity_mask);
 	}
 
 	return 0;
@@ -4181,7 +4175,8 @@ static int idpf_vport_intr_init_vec_idx(struct idpf_vport *vport)
 static void idpf_vport_intr_napi_add_all(struct idpf_vport *vport)
 {
 	int (*napi_poll)(struct napi_struct *napi, int budget);
-	u16 v_idx;
+	u16 v_idx, qv_idx;
+	int irq_num;
 
 	if (idpf_is_queue_model_split(vport->txq_model))
 		napi_poll = idpf_vport_splitq_napi_poll;
@@ -4190,12 +4185,12 @@ static void idpf_vport_intr_napi_add_all(struct idpf_vport *vport)
 
 	for (v_idx = 0; v_idx < vport->num_q_vectors; v_idx++) {
 		struct idpf_q_vector *q_vector = &vport->q_vectors[v_idx];
+		qv_idx = vport->q_vector_idxs[v_idx];
+		irq_num = vport->adapter->msix_entries[qv_idx].vector;
 
-		netif_napi_add(vport->netdev, &q_vector->napi, napi_poll);
-
-		/* only set affinity_mask if the CPU is online */
-		if (cpu_online(v_idx))
-			cpumask_set_cpu(v_idx, q_vector->affinity_mask);
+		netif_napi_add_config(vport->netdev, &q_vector->napi,
+				      napi_poll, v_idx);
+		netif_napi_set_irq(&q_vector->napi, irq_num);
 	}
 }
 
@@ -4239,9 +4234,6 @@ int idpf_vport_intr_alloc(struct idpf_vport *vport)
 		q_vector->rx_intr_mode = IDPF_ITR_DYNAMIC;
 		q_vector->rx_itr_idx = VIRTCHNL2_ITR_IDX_0;
 
-		if (!zalloc_cpumask_var(&q_vector->affinity_mask, GFP_KERNEL))
-			goto error;
-
 		q_vector->tx = kcalloc(txqs_per_vector, sizeof(*q_vector->tx),
 				       GFP_KERNEL);
 		if (!q_vector->tx)
diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.h b/drivers/net/ethernet/intel/idpf/idpf_txrx.h
index cd9a20c9cc7f..b029f566e57c 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_txrx.h
+++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.h
@@ -382,7 +382,6 @@ struct idpf_intr_reg {
  * @rx_intr_mode: Dynamic ITR or not
  * @rx_itr_idx: RX ITR index
  * @v_idx: Vector index
- * @affinity_mask: CPU affinity mask
  */
 struct idpf_q_vector {
 	__cacheline_group_begin_aligned(read_mostly);
@@ -419,13 +418,12 @@ struct idpf_q_vector {
 	__cacheline_group_begin_aligned(cold);
 	u16 v_idx;
 
-	cpumask_var_t affinity_mask;
 	__cacheline_group_end_aligned(cold);
 };
 libeth_cacheline_set_assert(struct idpf_q_vector, 120,
 			    24 + sizeof(struct napi_struct) +
 			    2 * sizeof(struct dim),
-			    8 + sizeof(cpumask_var_t));
+			    8);
 
 struct idpf_rx_queue_stats {
 	u64_stats_t packets;
@@ -921,7 +919,7 @@ static inline int idpf_q_vector_to_mem(const struct idpf_q_vector *q_vector)
 	if (!q_vector)
 		return NUMA_NO_NODE;
 
-	cpu = cpumask_first(q_vector->affinity_mask);
+	cpu = cpumask_first(&q_vector->napi.config->affinity_mask);
 
 	return cpu < nr_cpu_ids ? cpu_to_mem(cpu) : NUMA_NO_NODE;
 }
diff --git a/include/linux/cpu_rmap.h b/include/linux/cpu_rmap.h
index 20b5729903d7..2fd7ba75362a 100644
--- a/include/linux/cpu_rmap.h
+++ b/include/linux/cpu_rmap.h
@@ -32,6 +32,7 @@ struct cpu_rmap {
 #define CPU_RMAP_DIST_INF 0xffff
 
 extern struct cpu_rmap *alloc_cpu_rmap(unsigned int size, gfp_t flags);
+extern void cpu_rmap_get(struct cpu_rmap *rmap);
 extern int cpu_rmap_put(struct cpu_rmap *rmap);
 
 extern int cpu_rmap_add(struct cpu_rmap *rmap, void *obj);
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 9a387d456592..2094d3edda73 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -352,6 +352,7 @@ struct napi_config {
 	u64 gro_flush_timeout;
 	u64 irq_suspend_timeout;
 	u32 defer_hard_irqs;
+	cpumask_t affinity_mask;
 	unsigned int napi_id;
 };
 
@@ -394,6 +395,8 @@ struct napi_struct {
 	struct list_head	dev_list;
 	struct hlist_node	napi_hash_node;
 	int			irq;
+	struct irq_affinity_notify notify;
+	int			napi_rmap_idx;
 	int			index;
 	struct napi_config	*config;
 };
@@ -409,6 +412,7 @@ enum {
 	NAPI_STATE_PREFER_BUSY_POLL,	/* prefer busy-polling over softirq processing*/
 	NAPI_STATE_THREADED,		/* The poll is performed inside its own thread*/
 	NAPI_STATE_SCHED_THREADED,	/* Napi is currently scheduled in threaded mode */
+	NAPI_STATE_HAS_NOTIFIER,	/* Napi has an IRQ notifier */
 };
 
 enum {
@@ -422,6 +426,7 @@ enum {
 	NAPIF_STATE_PREFER_BUSY_POLL	= BIT(NAPI_STATE_PREFER_BUSY_POLL),
 	NAPIF_STATE_THREADED		= BIT(NAPI_STATE_THREADED),
 	NAPIF_STATE_SCHED_THREADED	= BIT(NAPI_STATE_SCHED_THREADED),
+	NAPIF_STATE_HAS_NOTIFIER	= BIT(NAPI_STATE_HAS_NOTIFIER),
 };
 
 enum gro_result {
@@ -1989,6 +1994,15 @@ enum netdev_reg_state {
  *
  *	@threaded:	napi threaded mode is enabled
  *
+ *	@irq_affinity_auto: driver wants the core to store and re-assign the IRQ
+ *			    affinity. Set by netif_enable_irq_affinity(), then
+ *			    the driver must create a persistent napi by
+ *			    netif_napi_add_config() and finally bind the napi to
+ *			    IRQ (via netif_napi_set_irq()).
+ *
+ *	@rx_cpu_rmap_auto: driver wants the core to manage the ARFS rmap.
+ *	                   Set by calling netif_enable_cpu_rmap().
+ *
  *	@see_all_hwtstamp_requests: device wants to see calls to
  *			ndo_hwtstamp_set() for all timestamp requests
  *			regardless of source, even if those aren't
@@ -2396,6 +2410,8 @@ struct net_device {
 	struct lock_class_key	*qdisc_tx_busylock;
 	bool			proto_down;
 	bool			threaded;
+	bool			irq_affinity_auto;
+	bool			rx_cpu_rmap_auto;
 
 	/* priv_flags_slow, ungrouped to save space */
 	unsigned long		see_all_hwtstamp_requests:1;
@@ -2724,10 +2740,7 @@ static inline void netdev_assert_locked_or_invisible(struct net_device *dev)
 		netdev_assert_locked(dev);
 }
 
-static inline void netif_napi_set_irq_locked(struct napi_struct *napi, int irq)
-{
-	napi->irq = irq;
-}
+void netif_napi_set_irq_locked(struct napi_struct *napi, int irq);
 
 static inline void netif_napi_set_irq(struct napi_struct *napi, int irq)
 {
@@ -2865,6 +2878,9 @@ static inline void netif_napi_del(struct napi_struct *napi)
 	synchronize_net();
 }
 
+int netif_enable_cpu_rmap(struct net_device *dev, unsigned int num_irqs);
+void netif_set_affinity_auto(struct net_device *dev);
+
 struct packet_type {
 	__be16			type;	/* This is really htons(ether_type). */
 	bool			ignore_outgoing;
diff --git a/lib/cpu_rmap.c b/lib/cpu_rmap.c
index 4c348670da31..f03d9be3f06b 100644
--- a/lib/cpu_rmap.c
+++ b/lib/cpu_rmap.c
@@ -73,7 +73,7 @@ static void cpu_rmap_release(struct kref *ref)
  * cpu_rmap_get - internal helper to get new ref on a cpu_rmap
  * @rmap: reverse-map allocated with alloc_cpu_rmap()
  */
-static inline void cpu_rmap_get(struct cpu_rmap *rmap)
+void cpu_rmap_get(struct cpu_rmap *rmap)
 {
 	kref_get(&rmap->refcount);
 }
diff --git a/net/core/dev.c b/net/core/dev.c
index 3f525278a871..b0ab0169f507 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6943,11 +6943,175 @@ void netif_queue_set_napi(struct net_device *dev, unsigned int queue_index,
 }
 EXPORT_SYMBOL(netif_queue_set_napi);
 
+static void
+netif_napi_irq_notify(struct irq_affinity_notify *notify,
+		      const cpumask_t *mask)
+{
+	struct napi_struct *napi =
+		container_of(notify, struct napi_struct, notify);
+#ifdef CONFIG_RFS_ACCEL
+	struct cpu_rmap *rmap = napi->dev->rx_cpu_rmap;
+	int err;
+#endif
+
+	if (napi->config && napi->dev->irq_affinity_auto)
+		cpumask_copy(&napi->config->affinity_mask, mask);
+
+#ifdef CONFIG_RFS_ACCEL
+	if (napi->dev->rx_cpu_rmap_auto) {
+		err = cpu_rmap_update(rmap, napi->napi_rmap_idx, mask);
+		if (err)
+			netdev_warn(napi->dev, "RMAP update failed (%d)\n",
+				    err);
+	}
+#endif
+}
+
+#ifdef CONFIG_RFS_ACCEL
+static void netif_napi_affinity_release(struct kref *ref)
+{
+	struct napi_struct *napi =
+		container_of(ref, struct napi_struct, notify.kref);
+	struct cpu_rmap *rmap = napi->dev->rx_cpu_rmap;
+
+	netdev_assert_locked(napi->dev);
+	WARN_ON(test_and_clear_bit(NAPI_STATE_HAS_NOTIFIER,
+				   &napi->state));
+
+	if (!napi->dev->rx_cpu_rmap_auto)
+		return;
+	rmap->obj[napi->napi_rmap_idx] = NULL;
+	napi->napi_rmap_idx = -1;
+	cpu_rmap_put(rmap);
+}
+
+int netif_enable_cpu_rmap(struct net_device *dev, unsigned int num_irqs)
+{
+	if (dev->rx_cpu_rmap_auto)
+		return 0;
+
+	dev->rx_cpu_rmap = alloc_irq_cpu_rmap(num_irqs);
+	if (!dev->rx_cpu_rmap)
+		return -ENOMEM;
+
+	dev->rx_cpu_rmap_auto = true;
+	return 0;
+}
+EXPORT_SYMBOL(netif_enable_cpu_rmap);
+
+static void netif_del_cpu_rmap(struct net_device *dev)
+{
+	struct cpu_rmap *rmap = dev->rx_cpu_rmap;
+
+	if (!dev->rx_cpu_rmap_auto)
+		return;
+
+	/* Free the rmap */
+	cpu_rmap_put(rmap);
+	dev->rx_cpu_rmap = NULL;
+	dev->rx_cpu_rmap_auto = false;
+}
+
+#else
+static void netif_napi_affinity_release(struct kref *ref)
+{
+}
+
+int netif_enable_cpu_rmap(struct net_device *dev, unsigned int num_irqs)
+{
+	return 0;
+}
+EXPORT_SYMBOL(netif_enable_cpu_rmap);
+
+static void netif_del_cpu_rmap(struct net_device *dev)
+{
+}
+#endif
+
+void netif_set_affinity_auto(struct net_device *dev)
+{
+	unsigned int i, maxqs, numa;
+
+	maxqs = max(dev->num_tx_queues, dev->num_rx_queues);
+	numa = dev_to_node(&dev->dev);
+
+	for (i = 0; i < maxqs; i++)
+		cpumask_set_cpu(cpumask_local_spread(i, numa),
+				&dev->napi_config[i].affinity_mask);
+
+	dev->irq_affinity_auto = true;
+}
+EXPORT_SYMBOL(netif_set_affinity_auto);
+
+void netif_napi_set_irq_locked(struct napi_struct *napi, int irq)
+{
+	int rc;
+
+	netdev_assert_locked_or_invisible(napi->dev);
+
+	if (napi->irq == irq)
+		return;
+
+	/* Remove existing resources */
+	if (test_and_clear_bit(NAPI_STATE_HAS_NOTIFIER, &napi->state))
+		irq_set_affinity_notifier(napi->irq, NULL);
+
+	napi->irq = irq;
+	if (irq < 0 ||
+	    (!napi->dev->rx_cpu_rmap_auto && !napi->dev->irq_affinity_auto))
+		return;
+
+	/* Abort for buggy drivers */
+	if (napi->dev->irq_affinity_auto && WARN_ON_ONCE(!napi->config))
+		return;
+
+#ifdef CONFIG_RFS_ACCEL
+	if (napi->dev->rx_cpu_rmap_auto) {
+		rc = cpu_rmap_add(napi->dev->rx_cpu_rmap, napi);
+		if (rc < 0)
+			return;
+
+		cpu_rmap_get(napi->dev->rx_cpu_rmap);
+		napi->napi_rmap_idx = rc;
+	}
+#endif
+
+	/* Use core IRQ notifier */
+	napi->notify.notify = netif_napi_irq_notify;
+	napi->notify.release = netif_napi_affinity_release;
+	rc = irq_set_affinity_notifier(irq, &napi->notify);
+	if (rc) {
+		netdev_warn(napi->dev, "Unable to set IRQ notifier (%d)\n",
+			    rc);
+		goto put_rmap;
+	}
+
+	set_bit(NAPI_STATE_HAS_NOTIFIER, &napi->state);
+	return;
+
+put_rmap:
+#ifdef CONFIG_RFS_ACCEL
+	if (napi->dev->rx_cpu_rmap_auto) {
+		cpu_rmap_put(napi->dev->rx_cpu_rmap);
+		napi->dev->rx_cpu_rmap->obj[napi->napi_rmap_idx] = NULL;
+		napi->napi_rmap_idx = -1;
+	}
+#endif
+	napi->notify.notify = NULL;
+	napi->notify.release = NULL;
+}
+EXPORT_SYMBOL(netif_napi_set_irq_locked);
+
 static void napi_restore_config(struct napi_struct *n)
 {
 	n->defer_hard_irqs = n->config->defer_hard_irqs;
 	n->gro_flush_timeout = n->config->gro_flush_timeout;
 	n->irq_suspend_timeout = n->config->irq_suspend_timeout;
+
+	if (n->dev->irq_affinity_auto &&
+	    test_bit(NAPI_STATE_HAS_NOTIFIER, &n->state))
+		irq_set_affinity(n->irq, &n->config->affinity_mask);
+
 	/* a NAPI ID might be stored in the config, if so use it. if not, use
 	 * napi_hash_add to generate one for us.
 	 */
@@ -7168,6 +7332,9 @@ void __netif_napi_del_locked(struct napi_struct *napi)
 	/* Make sure NAPI is disabled (or was never enabled). */
 	WARN_ON(!test_bit(NAPI_STATE_SCHED, &napi->state));
 
+	if (test_and_clear_bit(NAPI_STATE_HAS_NOTIFIER, &napi->state))
+		irq_set_affinity_notifier(napi->irq, NULL);
+
 	if (napi->config) {
 		napi->index = -1;
 		napi->config = NULL;
@@ -11720,6 +11887,8 @@ void free_netdev(struct net_device *dev)
 
 	netdev_napi_exit(dev);
 
+	netif_del_cpu_rmap(dev);
+
 	ref_tracker_dir_exit(&dev->refcnt_tracker);
 #ifdef CONFIG_PCPU_DEV_REFCNT
 	free_percpu(dev->pcpu_refcnt);
diff --git a/tools/testing/selftests/drivers/net/hw/Makefile b/tools/testing/selftests/drivers/net/hw/Makefile
index b2be14d0cc56..cde5814ff9a7 100644
--- a/tools/testing/selftests/drivers/net/hw/Makefile
+++ b/tools/testing/selftests/drivers/net/hw/Makefile
@@ -10,6 +10,7 @@ TEST_PROGS = \
 	ethtool_rmon.sh \
 	hw_stats_l3.sh \
 	hw_stats_l3_gre.sh \
+	irq.py \
 	loopback.sh \
 	nic_link_layer.py \
 	nic_performance.py \
@@ -34,9 +35,12 @@ TEST_INCLUDES := \
 # YNL files, must be before "include ..lib.mk"
 YNL_GEN_FILES := ncdevmem
 TEST_GEN_FILES += $(YNL_GEN_FILES)
+TEST_GEN_FILES += $(patsubst %.c,%.o,$(wildcard *.bpf.c))
 
 include ../../../lib.mk
 
 # YNL build
 YNL_GENS := ethtool netdev
 include ../../../net/ynl.mk
+
+include ../../../net/bpf.mk
diff --git a/tools/testing/selftests/drivers/net/hw/irq.py b/tools/testing/selftests/drivers/net/hw/irq.py
new file mode 100755
index 000000000000..42ab98370245
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/hw/irq.py
@@ -0,0 +1,99 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+from lib.py import ksft_run, ksft_exit
+from lib.py import ksft_ge, ksft_eq
+from lib.py import KsftSkipEx
+from lib.py import ksft_disruptive
+from lib.py import EthtoolFamily, NetdevFamily
+from lib.py import NetDrvEnv
+from lib.py import cmd, ip, defer
+
+
+def read_affinity(irq) -> str:
+    with open(f'/proc/irq/{irq}/smp_affinity', 'r') as fp:
+        return fp.read().lstrip("0,").strip()
+
+
+def write_affinity(irq, what) -> str:
+    if what != read_affinity(irq):
+        with open(f'/proc/irq/{irq}/smp_affinity', 'w') as fp:
+            fp.write(what)
+
+
+def check_irqs_reported(cfg) -> None:
+    """ Check that device reports IRQs for NAPI instances """
+    napis = cfg.netnl.napi_get({"ifindex": cfg.ifindex}, dump=True)
+    irqs = sum(['irq' in x for x in napis])
+
+    ksft_ge(irqs, 1)
+    ksft_eq(irqs, len(napis))
+
+
+def _check_reconfig(cfg, reconfig_cb) -> None:
+    napis = cfg.netnl.napi_get({"ifindex": cfg.ifindex}, dump=True)
+    for n in reversed(napis):
+        if 'irq' in n:
+            break
+    else:
+        raise KsftSkipEx(f"Device has no NAPI with IRQ attribute (#napis: {len(napis)}")
+
+    old = read_affinity(n['irq'])
+    # pick an affinity that's not the current one
+    new = "3" if old != "3" else "5"
+    write_affinity(n['irq'], new)
+    defer(write_affinity, n['irq'], old)
+
+    reconfig_cb(cfg)
+
+    ksft_eq(read_affinity(n['irq']), new, comment="IRQ affinity changed after reconfig")
+
+
+def check_reconfig_queues(cfg) -> None:
+    def reconfig(cfg) -> None:
+        channels = cfg.ethnl.channels_get({'header': {'dev-index': cfg.ifindex}})
+        if channels['combined-count'] == 0:
+            rx_type = 'rx'
+        else:
+            rx_type = 'combined'
+        cur_queue_cnt = channels[f'{rx_type}-count']
+        max_queue_cnt = channels[f'{rx_type}-max']
+
+        cmd(f"ethtool -L {cfg.ifname} {rx_type} 1")
+        cmd(f"ethtool -L {cfg.ifname} {rx_type} {max_queue_cnt}")
+        cmd(f"ethtool -L {cfg.ifname} {rx_type} {cur_queue_cnt}")
+
+    _check_reconfig(cfg, reconfig)
+
+
+def check_reconfig_xdp(cfg) -> None:
+    def reconfig(cfg) -> None:
+        ip(f"link set dev %s xdp obj %s sec xdp" %
+            (cfg.ifname, cfg.rpath("xdp_dummy.bpf.o")))
+        ip(f"link set dev %s xdp off" % cfg.ifname)
+
+    _check_reconfig(cfg, reconfig)
+
+
+@ksft_disruptive
+def check_down(cfg) -> None:
+    def reconfig(cfg) -> None:
+        ip("link set dev %s down" % cfg.ifname)
+        ip("link set dev %s up" % cfg.ifname)
+
+    _check_reconfig(cfg, reconfig)
+
+
+def main() -> None:
+    with NetDrvEnv(__file__, nsim_test=False) as cfg:
+        cfg.ethnl = EthtoolFamily()
+        cfg.netnl = NetdevFamily()
+
+        ksft_run([check_irqs_reported, check_reconfig_queues,
+                  check_reconfig_xdp, check_down],
+                 args=(cfg, ))
+    ksft_exit()
+
+
+if __name__ == "__main__":
+    main()
diff --git a/tools/testing/selftests/drivers/net/hw/xdp_dummy.bpf.c b/tools/testing/selftests/drivers/net/hw/xdp_dummy.bpf.c
new file mode 100644
index 000000000000..d988b2e0cee8
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/hw/xdp_dummy.bpf.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define KBUILD_MODNAME "xdp_dummy"
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+SEC("xdp")
+int xdp_dummy_prog(struct xdp_md *ctx)
+{
+	return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/drivers/net/lib/py/env.py b/tools/testing/selftests/drivers/net/lib/py/env.py
index 96b33b5ef9dd..fd4d674e6c72 100644
--- a/tools/testing/selftests/drivers/net/lib/py/env.py
+++ b/tools/testing/selftests/drivers/net/lib/py/env.py
@@ -58,14 +58,20 @@ class NetDrvEnv(NetDrvEnvBase):
     """
     Class for a single NIC / host env, with no remote end
     """
-    def __init__(self, src_path, **kwargs):
+    def __init__(self, src_path, nsim_test=None, **kwargs):
         super().__init__(src_path)
 
         self._ns = None
 
         if 'NETIF' in self.env:
+            if nsim_test is True:
+                raise KsftXfailEx("Test only works on netdevsim")
+
             self.dev = ip("-d link show dev " + self.env['NETIF'], json=True)[0]
         else:
+            if nsim_test is False:
+                raise KsftXfailEx("Test does not work on netdevsim")
+
             self._ns = NetdevSimDev(**kwargs)
             self.dev = self._ns.nsims[0].dev
         self.ifname = self.dev['ifname']