Commit 03d4f879 authored Mar 27, 2007 by Eric Dumazet Committed by David S. Miller Apr 25, 2007

[IPV4]: align inet_protos[] on SMP



As IPPROTO_TCP is 6, it makes sense to make sure inet_protos[] array
is properly cache line aligned to avoid false sharing on SMP.

c0680540 b peer_total
c0680544 b inet_peer_unused_head
c0680560 B inet_protos

On i386 this example, we can see that inet_protos[IPPROTO_TCP] shares
a potentially hot (and modified) cache line.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 4103f8cd

net/ipv4/protocol.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -45,7 +45,7 @@
		#include <net/ipip.h>
		#include <linux/igmp.h>

		struct net_protocol *inet_protos[MAX_INET_PROTOS];
		struct net_protocol *inet_protos[MAX_INET_PROTOS] ____cacheline_aligned_in_smp;
		static DEFINE_SPINLOCK(inet_proto_lock);

		/*

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