diff options
| author | Eric Dumazet <dada1@cosmosbay.com> | 2005-12-22 12:49:22 -0800 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2006-01-03 13:11:15 -0800 |
| commit | 90ddc4f0470427df306f308ad03db6b6b21644b8 (patch) | |
| tree | f97c1d57b25585394ebbd4b42b8d42a339f98644 /include/linux/net.h | |
| parent | 77d76ea310b50a9c8ff15bd290fcb4ed4961adf2 (diff) | |
[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/net.h')
| -rw-r--r-- | include/linux/net.h | 4 |
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, \ |