[PATCH][RFC 4] cleaning up struct sock

[Arnaldo Carvalho de Melo <acme@conectiva.com.br>]

Em Fri, Dec 21, 2001 at 11:54:38AM -0200, Arnaldo Carvalho de Melo escreveu:
> Em Thu, Dec 20, 2001 at 12:21:26AM -0800, David S. Miller escreveu:
> > I'd rather you pass the "kmem_cache_t" directly into sk_alloc, use
> > NULL for "I don't have any extra private area".
> > 
> > And then, for the IP case lay it out like this:
> > 
> > 	struct sock
> > 	struct ip_opt
> > 	struct {tcp,raw4,...}_opt
> > 
> > And use different kmem_cache_t's for each protocol instead of
> > the same one for tcp, raw4, etc.
> > 
> > RAW/UDP sockets waste a lot of space with your current layout.

Done, patch available at:

http://www.kernel.org/pub/linux/kernel/people/acme/v2.5/2.5.2-pre1/
sock.cleanup-2.5.2-pre1.bz2

Current state of /proc/slabinfo:

[acme@rama2 acme]$ grep sock /proc/slabinfo
unix_sock   7  20  400  1  2  1 :  17  572 2 0  0
raw4_sock   0  10  376  0  1  1 :   1    3 1 0  0
udp_sock    6  10  372  1  1  1 :   7   31 1 0  0
tcp_sock   13  15  800  3  3  1 :  14   47 3 0  0
sock        0   0  336  0  0  1 :   0    0 0 0  0

TODO: do the same for IPv6, that now has only one slabcache for all its
protocols.

- Arnaldo