From 90ddc4f0470427df306f308ad03db6b6b21644b8 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 22 Dec 2005 12:49:22 -0800 Subject: [NET]: move struct proto_ops to const I noticed that some of 'struct proto_ops' used in the kernel may share a cache line used by locks or other heavily modified data. (default linker alignement is 32 bytes, and L1_CACHE_LINE is 64 or 128 at least) This patch makes sure a 'struct proto_ops' can be declared as const, so that all cpus can share all parts of it without false sharing. This is not mandatory : a driver can still use a read/write structure if it needs to (and eventually a __read_mostly) I made a global stubstitute to change all existing occurences to make them const. This should reduce the possibility of false sharing on SMP, and speedup some socket system calls. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/sctp/ipv6.c | 2 +- net/sctp/protocol.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'net/sctp') diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c index fa3be2b8fb5f..15c05165c905 100644 --- a/net/sctp/ipv6.c +++ b/net/sctp/ipv6.c @@ -866,7 +866,7 @@ static int sctp_inet6_supported_addrs(const struct sctp_sock *opt, return 2; } -static struct proto_ops inet6_seqpacket_ops = { +static const struct proto_ops inet6_seqpacket_ops = { .family = PF_INET6, .owner = THIS_MODULE, .release = inet6_release, diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c index f775d78aa59d..d1b0747a5b9d 100644 --- a/net/sctp/protocol.c +++ b/net/sctp/protocol.c @@ -829,7 +829,7 @@ static struct notifier_block sctp_inetaddr_notifier = { }; /* Socket operations. */ -static struct proto_ops inet_seqpacket_ops = { +static const struct proto_ops inet_seqpacket_ops = { .family = PF_INET, .owner = THIS_MODULE, .release = inet_release, /* Needs to be wrapped... */ -- cgit v1.2.3