diff mbox series

[net-next,4/9] net: avoid dirtying sk->sk_rx_queue_mapping

Message ID 20211021162253.333616-7-eric.dumazet@gmail.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series tcp: receive path optimizations | expand

Checks

Context Check Description
netdev/apply fail Patch does not apply to net-next
netdev/tree_selection success Clearly marked for net-next

Commit Message

Eric Dumazet Oct. 21, 2021, 4:22 p.m. UTC 
From: Eric Dumazet <edumazet@google.com>

sk_rx_queue_mapping is located in a cache line that should be kept read mostly.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/net/sock.h | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/include/net/sock.h b/include/net/sock.h
index 99c4194cb61add848e3a35db0f952c4193f5ea1f..b4d3744b188ad869b4ec55f78e04236b710898de 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1916,10 +1916,8 @@  static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
 	if (skb_rx_queue_recorded(skb)) {
 		u16 rx_queue = skb_get_rx_queue(skb);
 
-		if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
-			return;
-
-		sk->sk_rx_queue_mapping = rx_queue;
+		if (unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
+			WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
 	}
 #endif
 }