[PATCH net-next 03/18] net: move netdev_tstamp_prequeue into net_hotdata

[Eric Dumazet <edumazet@google.com>]

netdev_tstamp_prequeue is used in rx path.

Move it to net_hotdata for better cache locality.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/net/hotdata.h      |  1 +
 net/core/dev.c             | 10 +++++-----
 net/core/dev.h             |  1 -
 net/core/hotdata.c         |  2 ++
 net/core/sysctl_net_core.c |  2 +-
 5 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/include/net/hotdata.h b/include/net/hotdata.h
index 72170223385ebe65cce42f762b3686c072291d36..149e56528537d8ed3365e46d6dc96e39c73a733a 100644
--- a/include/net/hotdata.h
+++ b/include/net/hotdata.h
@@ -10,6 +10,7 @@ struct net_hotdata {
 	int			gro_normal_batch;
 	int			netdev_budget;
 	int			netdev_budget_usecs;
+	int			tstamp_prequeue;
 };
 
 extern struct net_hotdata net_hotdata;
diff --git a/net/core/dev.c b/net/core/dev.c
index 0102a1810e7b148f465b87886b743e3d12c0e578..53ebdb55e8b7c0a6522eb3fdbb7bdd00948eb9a5 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4408,7 +4408,6 @@ EXPORT_SYMBOL(__dev_direct_xmit);
 int netdev_max_backlog __read_mostly = 1000;
 EXPORT_SYMBOL(netdev_max_backlog);
 
-int netdev_tstamp_prequeue __read_mostly = 1;
 unsigned int sysctl_skb_defer_max __read_mostly = 64;
 int weight_p __read_mostly = 64;           /* old backlog weight */
 int dev_weight_rx_bias __read_mostly = 1;  /* bias for backlog weight */
@@ -5052,7 +5051,7 @@ static int netif_rx_internal(struct sk_buff *skb)
 {
 	int ret;
 
-	net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
+	net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), skb);
 
 	trace_netif_rx(skb);
 
@@ -5344,7 +5343,7 @@ static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc,
 	int ret = NET_RX_DROP;
 	__be16 type;
 
-	net_timestamp_check(!READ_ONCE(netdev_tstamp_prequeue), skb);
+	net_timestamp_check(!READ_ONCE(net_hotdata.tstamp_prequeue), skb);
 
 	trace_netif_receive_skb(skb);
 
@@ -5728,7 +5727,7 @@ static int netif_receive_skb_internal(struct sk_buff *skb)
 {
 	int ret;
 
-	net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
+	net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), skb);
 
 	if (skb_defer_rx_timestamp(skb))
 		return NET_RX_SUCCESS;
@@ -5758,7 +5757,8 @@ void netif_receive_skb_list_internal(struct list_head *head)
 
 	INIT_LIST_HEAD(&sublist);
 	list_for_each_entry_safe(skb, next, head, list) {
-		net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
+		net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue),
+				    skb);
 		skb_list_del_init(skb);
 		if (!skb_defer_rx_timestamp(skb))
 			list_add_tail(&skb->list, &sublist);
diff --git a/net/core/dev.h b/net/core/dev.h
index 9a6170530850c78508f9234ec82b174f4bf5a4a3..2bcaf8eee50c179db2ca59880521b9be6ecd45c8 100644
--- a/net/core/dev.h
+++ b/net/core/dev.h
@@ -39,7 +39,6 @@ void dev_addr_check(struct net_device *dev);
 
 /* sysctls not referred to from outside net/core/ */
 extern unsigned int	sysctl_skb_defer_max;
-extern int		netdev_tstamp_prequeue;
 extern int		netdev_unregister_timeout_secs;
 extern int		weight_p;
 extern int		dev_weight_rx_bias;
diff --git a/net/core/hotdata.c b/net/core/hotdata.c
index 907d69120397dfb8d5a901912b72580fe256c762..087c4c84987df07f11a87112a778a5cac608a654 100644
--- a/net/core/hotdata.c
+++ b/net/core/hotdata.c
@@ -12,4 +12,6 @@ struct net_hotdata net_hotdata __cacheline_aligned = {
 	.netdev_budget = 300,
 	/* Must be at least 2 jiffes to guarantee 1 jiffy timeout */
 	.netdev_budget_usecs = 2 * USEC_PER_SEC / HZ,
+
+	.tstamp_prequeue = 1,
 };
diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
index a9c2d798b219506da75a5d0a30d490ff4011d668..bddd07da099886f2747f2ac4ba39a482b0f4231d 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -499,7 +499,7 @@ static struct ctl_table net_core_table[] = {
 #endif
 	{
 		.procname	= "netdev_tstamp_prequeue",
-		.data		= &netdev_tstamp_prequeue,
+		.data		= &net_hotdata.tstamp_prequeue,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec
-- 
2.44.0.278.ge034bb2e1d-goog