Re: [PATCH 2.6.25] netns: struct net content re-work

[ebiederm@xmission.com (Eric W. Biederman)]

Kirill Korotaev <dev@sw.ru> writes:

> Daniel Lezcano wrote:
>> Denis V. Lunev wrote:
>> 
>>>Recently David Miller and Herbert Xu pointed out that struct net becomes
>>>overbloated and un-maintainable. There are two solutions:
>>>- provide a pointer to a network subsystem definition from struct net.
>>>  This costs an additional dereferrence
>>>- place sub-system definition into the structure itself. This will speedup
>>>  run-time access at the cost of recompilation time
>>>
>>>The second approach looks better for us. 
>> 
>> 
>> Yes, we do not need/want a pointer in this structure and add more 
>> dereference in the network code.

If it does go that way we just carefully pass around a properly
typed structure in that subsystem to reduce the cost.  Still 
it would be nice not to need to add the extra pointer.

>>>index b62e31f..f60e1ce 100644
>>>--- a/include/net/net_namespace.h
>>>+++ b/include/net/net_namespace.h
>>>@@ -8,6 +8,8 @@
>>> #include <linux/workqueue.h>
>>> #include <linux/list.h>
>>>
>>>+#include <net/netns/unix.h>
>>>+
>>> struct proc_dir_entry;
>>> struct net_device;
>>> struct sock;
>>>@@ -46,8 +48,7 @@ struct net {
>>> 	struct hlist_head	packet_sklist;
>>>
>>> 	/* unix sockets */
>>>-	int			sysctl_unix_max_dgram_qlen;
>>>-	struct ctl_table_header	*unix_ctl;
>>>+	struct netns_unix	unx;
>> 
>> 
>> Can you change this from unx to unix ?
>
> no, it won't compile. Guess why :)

Hmm.  It looks like it is a #define somewhere gcc?
Eric