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/atm/pvc.c | 2 +- net/atm/svc.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'net/atm') diff --git a/net/atm/pvc.c b/net/atm/pvc.c index 2684a92da22b..f2c541774dcd 100644 --- a/net/atm/pvc.c +++ b/net/atm/pvc.c @@ -102,7 +102,7 @@ static int pvc_getname(struct socket *sock,struct sockaddr *sockaddr, } -static struct proto_ops pvc_proto_ops = { +static const struct proto_ops pvc_proto_ops = { .family = PF_ATMPVC, .owner = THIS_MODULE, diff --git a/net/atm/svc.c b/net/atm/svc.c index d7b266136bf6..3a180cfd7b48 100644 --- a/net/atm/svc.c +++ b/net/atm/svc.c @@ -613,7 +613,7 @@ static int svc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) return error; } -static struct proto_ops svc_proto_ops = { +static const struct proto_ops svc_proto_ops = { .family = PF_ATMSVC, .owner = THIS_MODULE, -- cgit v1.2.1