1 files changed, 0 insertions, 261 deletions
diff --git a/target/linux/generic/backport-5.4/601-v5.12-net-implement-threaded-able-napi-poll-loop-support.patch b/target/linux/generic/backport-5.4/601-v5.12-net-implement-threaded-able-napi-poll-loop-support.patch
deleted file mode 100644
index 0c548f331a..0000000000
--- a/target/linux/generic/backport-5.4/601-v5.12-net-implement-threaded-able-napi-poll-loop-support.patch
+++ /dev/null
@@ -1,261 +0,0 @@
-From: Wei Wang <weiwan@google.com>
-Date: Mon, 8 Feb 2021 11:34:09 -0800
-Subject: [PATCH] net: implement threaded-able napi poll loop support
-
-This patch allows running each napi poll loop inside its own
-kernel thread.
-The kthread is created during netif_napi_add() if dev->threaded
-is set. And threaded mode is enabled in napi_enable(). We will
-provide a way to set dev->threaded and enable threaded mode
-without a device up/down in the following patch.
-
-Once that threaded mode is enabled and the kthread is
-started, napi_schedule() will wake-up such thread instead
-of scheduling the softirq.
-
-The threaded poll loop behaves quite likely the net_rx_action,
-but it does not have to manipulate local irqs and uses
-an explicit scheduling point based on netdev_budget.
-
-Co-developed-by: Paolo Abeni <pabeni@redhat.com>
-Signed-off-by: Paolo Abeni <pabeni@redhat.com>
-Co-developed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
-Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
-Co-developed-by: Jakub Kicinski <kuba@kernel.org>
-Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-Signed-off-by: Wei Wang <weiwan@google.com>
-Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
-Signed-off-by: David S. Miller <davem@davemloft.net>
----
-
---- a/include/linux/netdevice.h
-+++ b/include/linux/netdevice.h
-@@ -340,6 +340,7 @@ struct napi_struct {
- 	struct list_head	dev_list;
- 	struct hlist_node	napi_hash_node;
- 	unsigned int		napi_id;
-+	struct task_struct	*thread;
- };
- 
- enum {
-@@ -350,6 +351,7 @@ enum {
- 	NAPI_STATE_HASHED,	/* In NAPI hash (busy polling possible) */
- 	NAPI_STATE_NO_BUSY_POLL,/* Do not add in napi_hash, no busy polling */
- 	NAPI_STATE_IN_BUSY_POLL,/* sk_busy_loop() owns this NAPI */
-+	NAPI_STATE_THREADED,		/* The poll is performed inside its own thread*/
- };
- 
- enum {
-@@ -360,6 +362,7 @@ enum {
- 	NAPIF_STATE_HASHED	 = BIT(NAPI_STATE_HASHED),
- 	NAPIF_STATE_NO_BUSY_POLL = BIT(NAPI_STATE_NO_BUSY_POLL),
- 	NAPIF_STATE_IN_BUSY_POLL = BIT(NAPI_STATE_IN_BUSY_POLL),
-+	NAPIF_STATE_THREADED	 = BIT(NAPI_STATE_THREADED),
- };
- 
- enum gro_result {
-@@ -504,20 +507,7 @@ bool napi_hash_del(struct napi_struct *n
-  */
- void napi_disable(struct napi_struct *n);
- 
--/**
-- *	napi_enable - enable NAPI scheduling
-- *	@n: NAPI context
-- *
-- * Resume NAPI from being scheduled on this context.
-- * Must be paired with napi_disable.
-- */
--static inline void napi_enable(struct napi_struct *n)
--{
--	BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
--	smp_mb__before_atomic();
--	clear_bit(NAPI_STATE_SCHED, &n->state);
--	clear_bit(NAPI_STATE_NPSVC, &n->state);
--}
-+void napi_enable(struct napi_struct *n);
- 
- /**
-  *	napi_synchronize - wait until NAPI is not running
-@@ -1783,6 +1773,8 @@ enum netdev_ml_priv_type {
-  *
-  *	@wol_enabled:	Wake-on-LAN is enabled
-  *
-+ *	@threaded:	napi threaded mode is enabled
-+ *
-  *	FIXME: cleanup struct net_device such that network protocol info
-  *	moves out.
-  */
-@@ -2075,6 +2067,7 @@ struct net_device {
- 	struct lock_class_key	addr_list_lock_key;
- 	bool			proto_down;
- 	unsigned		wol_enabled:1;
-+	unsigned		threaded:1;
- };
- #define to_net_dev(d) container_of(d, struct net_device, dev)
- 
---- a/net/core/dev.c
-+++ b/net/core/dev.c
-@@ -91,6 +91,7 @@
- #include <linux/etherdevice.h>
- #include <linux/ethtool.h>
- #include <linux/skbuff.h>
-+#include <linux/kthread.h>
- #include <linux/bpf.h>
- #include <linux/bpf_trace.h>
- #include <net/net_namespace.h>
-@@ -1289,6 +1290,27 @@ void netdev_notify_peers(struct net_devi
- }
- EXPORT_SYMBOL(netdev_notify_peers);
- 
-+static int napi_threaded_poll(void *data);
-+
-+static int napi_kthread_create(struct napi_struct *n)
-+{
-+	int err = 0;
-+
-+	/* Create and wake up the kthread once to put it in
-+	 * TASK_INTERRUPTIBLE mode to avoid the blocked task
-+	 * warning and work with loadavg.
-+	 */
-+	n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d",
-+				n->dev->name, n->napi_id);
-+	if (IS_ERR(n->thread)) {
-+		err = PTR_ERR(n->thread);
-+		pr_err("kthread_run failed with err %d\n", err);
-+		n->thread = NULL;
-+	}
-+
-+	return err;
-+}
-+
- static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack)
- {
- 	const struct net_device_ops *ops = dev->netdev_ops;
-@@ -3888,6 +3910,21 @@ int gro_normal_batch __read_mostly = 8;
- static inline void ____napi_schedule(struct softnet_data *sd,
- 				     struct napi_struct *napi)
- {
-+	struct task_struct *thread;
-+
-+	if (test_bit(NAPI_STATE_THREADED, &napi->state)) {
-+		/* Paired with smp_mb__before_atomic() in
-+		 * napi_enable(). Use READ_ONCE() to guarantee
-+		 * a complete read on napi->thread. Only call
-+		 * wake_up_process() when it's not NULL.
-+		 */
-+		thread = READ_ONCE(napi->thread);
-+		if (thread) {
-+			wake_up_process(thread);
-+			return;
-+		}
-+	}
-+
- 	list_add_tail(&napi->poll_list, &sd->poll_list);
- 	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
- }
-@@ -6279,6 +6316,12 @@ void netif_napi_add(struct net_device *d
- 	set_bit(NAPI_STATE_NPSVC, &napi->state);
- 	list_add_rcu(&napi->dev_list, &dev->napi_list);
- 	napi_hash_add(napi);
-+	/* Create kthread for this napi if dev->threaded is set.
-+	 * Clear dev->threaded if kthread creation failed so that
-+	 * threaded mode will not be enabled in napi_enable().
-+	 */
-+	if (dev->threaded && napi_kthread_create(napi))
-+		dev->threaded = 0;
- }
- EXPORT_SYMBOL(netif_napi_add);
- 
-@@ -6295,9 +6338,28 @@ void napi_disable(struct napi_struct *n)
- 	hrtimer_cancel(&n->timer);
- 
- 	clear_bit(NAPI_STATE_DISABLE, &n->state);
-+	clear_bit(NAPI_STATE_THREADED, &n->state);
- }
- EXPORT_SYMBOL(napi_disable);
- 
-+/**
-+ *	napi_enable - enable NAPI scheduling
-+ *	@n: NAPI context
-+ *
-+ * Resume NAPI from being scheduled on this context.
-+ * Must be paired with napi_disable.
-+ */
-+void napi_enable(struct napi_struct *n)
-+{
-+	BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
-+	smp_mb__before_atomic();
-+	clear_bit(NAPI_STATE_SCHED, &n->state);
-+	clear_bit(NAPI_STATE_NPSVC, &n->state);
-+	if (n->dev->threaded && n->thread)
-+		set_bit(NAPI_STATE_THREADED, &n->state);
-+}
-+EXPORT_SYMBOL(napi_enable);
-+
- static void flush_gro_hash(struct napi_struct *napi)
- {
- 	int i;
-@@ -6322,6 +6384,11 @@ void netif_napi_del(struct napi_struct *
- 
- 	flush_gro_hash(napi);
- 	napi->gro_bitmask = 0;
-+
-+	if (napi->thread) {
-+		kthread_stop(napi->thread);
-+		napi->thread = NULL;
-+	}
- }
- EXPORT_SYMBOL(netif_napi_del);
- 
-@@ -6401,6 +6468,51 @@ static int napi_poll(struct napi_struct
- 	return work;
- }
- 
-+static int napi_thread_wait(struct napi_struct *napi)
-+{
-+	set_current_state(TASK_INTERRUPTIBLE);
-+
-+	while (!kthread_should_stop() && !napi_disable_pending(napi)) {
-+		if (test_bit(NAPI_STATE_SCHED, &napi->state)) {
-+			WARN_ON(!list_empty(&napi->poll_list));
-+			__set_current_state(TASK_RUNNING);
-+			return 0;
-+		}
-+
-+		schedule();
-+		set_current_state(TASK_INTERRUPTIBLE);
-+	}
-+	__set_current_state(TASK_RUNNING);
-+	return -1;
-+}
-+
-+static int napi_threaded_poll(void *data)
-+{
-+	struct napi_struct *napi = data;
-+	void *have;
-+
-+	while (!napi_thread_wait(napi)) {
-+		for (;;) {
-+			bool repoll = false;
-+
-+			local_bh_disable();
-+
-+			have = netpoll_poll_lock(napi);
-+			__napi_poll(napi, &repoll);
-+			netpoll_poll_unlock(have);
-+
-+			__kfree_skb_flush();
-+			local_bh_enable();
-+
-+			if (!repoll)
-+				break;
-+
-+			cond_resched();
-+		}
-+	}
-+	return 0;
-+}
-+
- static __latent_entropy void net_rx_action(struct softirq_action *h)
- {
- 	struct softnet_data *sd = this_cpu_ptr(&softnet_data);