]> nv-tegra.nvidia Code Review - linux-2.6.git/commit
[NET]: move struct proto_ops to const
authorEric Dumazet <dada1@cosmosbay.com>
Thu, 22 Dec 2005 20:49:22 +0000 (12:49 -0800)
committerDavid S. Miller <davem@sunset.davemloft.net>
Tue, 3 Jan 2006 21:11:15 +0000 (13:11 -0800)
commit90ddc4f0470427df306f308ad03db6b6b21644b8
treef97c1d57b25585394ebbd4b42b8d42a339f98644
parent77d76ea310b50a9c8ff15bd290fcb4ed4961adf2
[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 <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
33 files changed:
include/linux/net.h
include/net/inet_common.h
include/net/ipv6.h
include/net/protocol.h
net/appletalk/ddp.c
net/atm/pvc.c
net/atm/svc.c
net/ax25/af_ax25.c
net/bluetooth/bnep/sock.c
net/bluetooth/cmtp/sock.c
net/bluetooth/hci_sock.c
net/bluetooth/hidp/sock.c
net/bluetooth/l2cap.c
net/bluetooth/rfcomm/sock.c
net/bluetooth/sco.c
net/dccp/proto.c
net/decnet/af_decnet.c
net/econet/af_econet.c
net/ipv4/af_inet.c
net/ipv6/af_inet6.c
net/ipx/af_ipx.c
net/irda/af_irda.c
net/key/af_key.c
net/llc/af_llc.c
net/netlink/af_netlink.c
net/netrom/af_netrom.c
net/packet/af_packet.c
net/sctp/ipv6.c
net/sctp/protocol.c
net/sunrpc/svcsock.c
net/unix/af_unix.c
net/wanrouter/af_wanpipe.c
net/x25/af_x25.c