net: move ptype_all into net_hotdata

ptype_all is used in rx/tx fast paths.

Move it to net_hotdata for better cache locality.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240306160031.874438-5-edumazet@google.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

include/linux/netdevice.h

@@ -5306,7 +5306,6 @@ static inline const char *netdev_reg_state(const struct net_device *dev)
 #define PTYPE_HASH_SIZE	(16)
 #define PTYPE_HASH_MASK	(PTYPE_HASH_SIZE - 1)
 
-extern struct list_head ptype_all __read_mostly;
 extern struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
 
 extern struct net_device *blackhole_netdev;

include/net/hotdata.h

@@ -7,6 +7,7 @@
 /* Read mostly data used in network fast paths. */
 struct net_hotdata {
 	struct list_head	offload_base;
+	struct list_head	ptype_all;
 	int			gro_normal_batch;
 	int			netdev_budget;
 	int			netdev_budget_usecs;

net/core/dev.c

@@ -161,7 +161,6 @@
 
 static DEFINE_SPINLOCK(ptype_lock);
 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
-struct list_head ptype_all __read_mostly;	/* Taps */
 
 static int netif_rx_internal(struct sk_buff *skb);
 static int call_netdevice_notifiers_extack(unsigned long val,
@@ -540,7 +539,7 @@ static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
 static inline struct list_head *ptype_head(const struct packet_type *pt)
 {
 	if (pt->type == htons(ETH_P_ALL))
-		return pt->dev ? &pt->dev->ptype_all : &ptype_all;
+		return pt->dev ? &pt->dev->ptype_all : &net_hotdata.ptype_all;
 	else
 		return pt->dev ? &pt->dev->ptype_specific :
 				 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
@@ -2226,7 +2225,8 @@ static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
  */
 bool dev_nit_active(struct net_device *dev)
 {
-	return !list_empty(&ptype_all) || !list_empty(&dev->ptype_all);
+	return !list_empty(&net_hotdata.ptype_all) ||
+	       !list_empty(&dev->ptype_all);
 }
 EXPORT_SYMBOL_GPL(dev_nit_active);
 
@@ -2237,10 +2237,9 @@ EXPORT_SYMBOL_GPL(dev_nit_active);
 
 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
 {
-	struct packet_type *ptype;
+	struct list_head *ptype_list = &net_hotdata.ptype_all;
+	struct packet_type *ptype, *pt_prev = NULL;
 	struct sk_buff *skb2 = NULL;
-	struct packet_type *pt_prev = NULL;
-	struct list_head *ptype_list = &ptype_all;
 
 	rcu_read_lock();
 again:
@@ -2286,7 +2285,7 @@ void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
 		pt_prev = ptype;
 	}
 
-	if (ptype_list == &ptype_all) {
+	if (ptype_list == &net_hotdata.ptype_all) {
 		ptype_list = &dev->ptype_all;
 		goto again;
 	}
@@ -5387,7 +5386,7 @@ static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc,
 	if (pfmemalloc)
 		goto skip_taps;
 
-	list_for_each_entry_rcu(ptype, &ptype_all, list) {
+	list_for_each_entry_rcu(ptype, &net_hotdata.ptype_all, list) {
 		if (pt_prev)
 			ret = deliver_skb(skb, pt_prev, orig_dev);
 		pt_prev = ptype;
@@ -11749,7 +11748,6 @@ static int __init net_dev_init(void)
 	if (netdev_kobject_init())
 		goto out;
 
-	INIT_LIST_HEAD(&ptype_all);
 	for (i = 0; i < PTYPE_HASH_SIZE; i++)
 		INIT_LIST_HEAD(&ptype_base[i]);
 

net/core/hotdata.c

@@ -7,6 +7,7 @@
 
 struct net_hotdata net_hotdata __cacheline_aligned = {
 	.offload_base = LIST_HEAD_INIT(net_hotdata.offload_base),
+	.ptype_all = LIST_HEAD_INIT(net_hotdata.ptype_all),
 	.gro_normal_batch = 8,
 
 	.netdev_budget = 300,

net/core/net-procfs.c

@@ -3,6 +3,7 @@
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <net/wext.h>
+#include <net/hotdata.h>
 
 #include "dev.h"
 
@@ -183,7 +184,7 @@ static void *ptype_get_idx(struct seq_file *seq, loff_t pos)
 		}
 	}
 
-	list_for_each_entry_rcu(pt, &ptype_all, list) {
+	list_for_each_entry_rcu(pt, &net_hotdata.ptype_all, list) {
 		if (i == pos)
 			return pt;
 		++i;
@@ -231,13 +232,13 @@ static void *ptype_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 			}
 		}
 
-		nxt = ptype_all.next;
+		nxt = net_hotdata.ptype_all.next;
 		goto ptype_all;
 	}
 
 	if (pt->type == htons(ETH_P_ALL)) {
 ptype_all:
-		if (nxt != &ptype_all)
+		if (nxt != &net_hotdata.ptype_all)
 			goto found;
 		hash = 0;
 		nxt = ptype_base[0].next;