Merge branch 'use-enum-to-represent-the-napi-threaded-state'

Samiullah Khawaja says:

====================
Use enum to represent the NAPI threaded state

Instead of using 0/1 to represent the NAPI threaded states use enum
(disabled/enabled) to represent the NAPI threaded states.

This patch series is a subset of patches from the following patch series:
https://lore.kernel.org/20250718232052.1266188-1-skhawaja@google.com

The first 3 patches are being sent separately as per the feedback to
replace the usage of 0/1 as NAPI threaded states with enum. See:
https://lore.kernel.org/20250721164856.1d2208e4@kernel.org
====================

Link: https://patch.msgid.link/20250723013031.2911384-1-skhawaja@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

5 files changed, 40 insertions, 17 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 354d3453b407..1c6e755841ce 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6578,8 +6578,7 @@ bool napi_complete_done(struct napi_struct *n, int work_done)
 	 * it, we need to bound somehow the time packets are kept in
 	 * the GRO layer.
 	 */
-	gro_flush(&n->gro, !!timeout);
-	gro_normal_list(&n->gro);
+	gro_flush_normal(&n->gro, !!timeout);
 
 	if (unlikely(!list_empty(&n->poll_list))) {
 		/* If n->poll_list is not empty, we need to mask irqs */
@@ -6649,8 +6648,7 @@ static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule)
 	}
 
 	/* Flush too old packets. If HZ < 1000, flush all packets */
-	gro_flush(&napi->gro, HZ >= 1000);
-	gro_normal_list(&napi->gro);
+	gro_flush_normal(&napi->gro, HZ >= 1000);
 
 	clear_bit(NAPI_STATE_SCHED, &napi->state);
 }
@@ -6965,7 +6963,8 @@ static void napi_stop_kthread(struct napi_struct *napi)
 	napi->thread = NULL;
 }
 
-int napi_set_threaded(struct napi_struct *napi, bool threaded)
+int napi_set_threaded(struct napi_struct *napi,
+		      enum netdev_napi_threaded threaded)
 {
 	if (threaded) {
 		if (!napi->thread) {
@@ -6990,7 +6989,8 @@ int napi_set_threaded(struct napi_struct *napi, bool threaded)
 	return 0;
 }
 
-int netif_set_threaded(struct net_device *dev, bool threaded)
+int netif_set_threaded(struct net_device *dev,
+		       enum netdev_napi_threaded threaded)
 {
 	struct napi_struct *napi;
 	int err = 0;
@@ -7002,7 +7002,7 @@ int netif_set_threaded(struct net_device *dev, bool threaded)
 			if (!napi->thread) {
 				err = napi_kthread_create(napi);
 				if (err) {
-					threaded = false;
+					threaded = NETDEV_NAPI_THREADED_DISABLED;
 					break;
 				}
 			}
@@ -7031,7 +7031,23 @@ int netif_set_threaded(struct net_device *dev, bool threaded)
 
 	return err;
 }
-EXPORT_SYMBOL(netif_set_threaded);
+
+/**
+ * netif_threaded_enable() - enable threaded NAPIs
+ * @dev: net_device instance
+ *
+ * Enable threaded mode for the NAPI instances of the device. This may be useful
+ * for devices where multiple NAPI instances get scheduled by a single
+ * interrupt. Threaded NAPI allows moving the NAPI processing to cores other
+ * than the core where IRQ is mapped.
+ *
+ * This function should be called before @dev is registered.
+ */
+void netif_threaded_enable(struct net_device *dev)
+{
+	WARN_ON_ONCE(netif_set_threaded(dev, NETDEV_NAPI_THREADED_ENABLED));
+}
+EXPORT_SYMBOL(netif_threaded_enable);
 
 /**
  * netif_queue_set_napi - Associate queue with the napi
@@ -7346,7 +7362,7 @@ void netif_napi_add_weight_locked(struct net_device *dev,
 	 * threaded mode will not be enabled in napi_enable().
 	 */
 	if (dev->threaded && napi_kthread_create(napi))
-		dev->threaded = false;
+		dev->threaded = NETDEV_NAPI_THREADED_DISABLED;
 	netif_napi_set_irq_locked(napi, -1);
 }
 EXPORT_SYMBOL(netif_napi_add_weight_locked);
@@ -7515,8 +7531,7 @@ static int __napi_poll(struct napi_struct *n, bool *repoll)
 	}
 
 	/* Flush too old packets. If HZ < 1000, flush all packets */
-	gro_flush(&n->gro, HZ >= 1000);
-	gro_normal_list(&n->gro);
+	gro_flush_normal(&n->gro, HZ >= 1000);
 
 	/* Some drivers may have called napi_schedule
 	 * prior to exhausting their budget.
diff --git a/net/core/dev.h b/net/core/dev.h
index a603387fb566..ab69edc0c3e3 100644
--- a/net/core/dev.h
+++ b/net/core/dev.h
@@ -315,12 +315,19 @@ static inline void napi_set_irq_suspend_timeout(struct napi_struct *n,
 	WRITE_ONCE(n->irq_suspend_timeout, timeout);
 }
 
-static inline bool napi_get_threaded(struct napi_struct *n)
+static inline enum netdev_napi_threaded napi_get_threaded(struct napi_struct *n)
 {
-	return test_bit(NAPI_STATE_THREADED, &n->state);
+	if (test_bit(NAPI_STATE_THREADED, &n->state))
+		return NETDEV_NAPI_THREADED_ENABLED;
+
+	return NETDEV_NAPI_THREADED_DISABLED;
 }
 
-int napi_set_threaded(struct napi_struct *n, bool threaded);
+int napi_set_threaded(struct napi_struct *n,
+		      enum netdev_napi_threaded threaded);
+
+int netif_set_threaded(struct net_device *dev,
+		       enum netdev_napi_threaded threaded);
 
 int rps_cpumask_housekeeping(struct cpumask *mask);
 
diff --git a/net/core/dev_api.c b/net/core/dev_api.c
index dd7f57013ce5..f28852078aa6 100644
--- a/net/core/dev_api.c
+++ b/net/core/dev_api.c
@@ -368,7 +368,8 @@ void netdev_state_change(struct net_device *dev)
 }
 EXPORT_SYMBOL(netdev_state_change);
 
-int dev_set_threaded(struct net_device *dev, bool threaded)
+int dev_set_threaded(struct net_device *dev,
+		     enum netdev_napi_threaded threaded)
 {
 	int ret;
 
diff --git a/net/core/netdev-genl-gen.c b/net/core/netdev-genl-gen.c
index 0994bd68a7e6..e9a2a6f26cb7 100644
--- a/net/core/netdev-genl-gen.c
+++ b/net/core/netdev-genl-gen.c
@@ -97,7 +97,7 @@ static const struct nla_policy netdev_napi_set_nl_policy[NETDEV_A_NAPI_THREADED
 	[NETDEV_A_NAPI_DEFER_HARD_IRQS] = NLA_POLICY_FULL_RANGE(NLA_U32, &netdev_a_napi_defer_hard_irqs_range),
 	[NETDEV_A_NAPI_GRO_FLUSH_TIMEOUT] = { .type = NLA_UINT, },
 	[NETDEV_A_NAPI_IRQ_SUSPEND_TIMEOUT] = { .type = NLA_UINT, },
-	[NETDEV_A_NAPI_THREADED] = NLA_POLICY_MAX(NLA_UINT, 1),
+	[NETDEV_A_NAPI_THREADED] = NLA_POLICY_MAX(NLA_U32, 1),
 };
 
 /* NETDEV_CMD_BIND_TX - do */
diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index 5875df372415..6314eb7bdf69 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -333,7 +333,7 @@ netdev_nl_napi_set_config(struct napi_struct *napi, struct genl_info *info)
 		int ret;
 
 		threaded = nla_get_uint(info->attrs[NETDEV_A_NAPI_THREADED]);
-		ret = napi_set_threaded(napi, !!threaded);
+		ret = napi_set_threaded(napi, threaded);
 		if (ret)
 			return ret;
 	}