summaryrefslogtreecommitdiff
path: root/include/linux
diff options
context:
space:
mode:
authorEric Dumazet <dada1@cosmosbay.com>2005-12-22 23:49:22 +0300
committerDavid S. Miller <davem@sunset.davemloft.net>2006-01-04 00:11:15 +0300
commit90ddc4f0470427df306f308ad03db6b6b21644b8 (patch)
treef97c1d57b25585394ebbd4b42b8d42a339f98644 /include/linux
parent77d76ea310b50a9c8ff15bd290fcb4ed4961adf2 (diff)
downloadlinux-90ddc4f0470427df306f308ad03db6b6b21644b8.tar.xz
[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>
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/net.h4
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/net.h b/include/linux/net.h
index d6a41e6577f6..28195a2d8ff0 100644
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -107,7 +107,7 @@ enum sock_type {
struct socket {
socket_state state;
unsigned long flags;
- struct proto_ops *ops;
+ const struct proto_ops *ops;
struct fasync_struct *fasync_list;
struct file *file;
struct sock *sk;
@@ -260,7 +260,7 @@ SOCKCALL_WRAP(name, recvmsg, (struct kiocb *iocb, struct socket *sock, struct ms
SOCKCALL_WRAP(name, mmap, (struct file *file, struct socket *sock, struct vm_area_struct *vma), \
(file, sock, vma)) \
\
-static struct proto_ops name##_ops = { \
+static const struct proto_ops name##_ops = { \
.family = fam, \
.owner = THIS_MODULE, \
.release = __lock_##name##_release, \