From: Eric Dumazet <edumazet@google.com>
Date: Mon, 30 Apr 2012 16:07:09 +0000 (+0000)
Subject: net: add a prefetch in socket backlog processing
X-Git-Tag: firefly_0821_release~3680^2~2787^2~209
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=e4cbb02a1070ebf0185f67a8887cc05f8a183d71;p=firefly-linux-kernel-4.4.55.git

net: add a prefetch in socket backlog processing

TCP or UDP stacks have big enough latencies that prefetching next
pointer is worth it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/core/sock.c b/net/core/sock.c
index 836bca6485f5..1a8835117fd6 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1700,6 +1700,7 @@ static void __release_sock(struct sock *sk)
 		do {
 			struct sk_buff *next = skb->next;
 
+			prefetch(next);
 			WARN_ON_ONCE(skb_dst_is_noref(skb));
 			skb->next = NULL;
 			sk_backlog_rcv(sk, skb);