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 /net/x25 | |
| parent | 77d76ea310b50a9c8ff15bd290fcb4ed4961adf2 (diff) | |
| download | lwn-90ddc4f0470427df306f308ad03db6b6b21644b8.tar.gz lwn-90ddc4f0470427df306f308ad03db6b6b21644b8.zip | |
[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 'net/x25')
| -rw-r--r-- | net/x25/af_x25.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c index 020d73cc8414..ca8b3b0b920d 100644 --- a/net/x25/af_x25.c +++ b/net/x25/af_x25.c @@ -64,7 +64,7 @@ int sysctl_x25_ack_holdback_timeout = X25_DEFAULT_T2; HLIST_HEAD(x25_list); DEFINE_RWLOCK(x25_list_lock); -static struct proto_ops x25_proto_ops; +static const struct proto_ops x25_proto_ops; static struct x25_address null_x25_address = {" "}; @@ -1391,7 +1391,7 @@ static struct net_proto_family x25_family_ops = { .owner = THIS_MODULE, }; -static struct proto_ops SOCKOPS_WRAPPED(x25_proto_ops) = { +static const struct proto_ops SOCKOPS_WRAPPED(x25_proto_ops) = { .family = AF_X25, .owner = THIS_MODULE, .release = x25_release, |