46ca5f5dc4
[acme@newtoy net-2.6.20]$ pahole net/ipv4/tcp.o xfrm_policy /* /pub/scm/linux/kernel/git/acme/net-2.6.20/include/linux/security.h:67 */ struct xfrm_policy { struct xfrm_policy * next; /* 0 4 */ struct hlist_node bydst; /* 4 8 */ struct hlist_node byidx; /* 12 8 */ rwlock_t lock; /* 20 36 */ atomic_t refcnt; /* 56 4 */ struct timer_list timer; /* 60 24 */ u8 type; /* 84 1 */ /* XXX 3 bytes hole, try to pack */ u32 priority; /* 88 4 */ u32 index; /* 92 4 */ struct xfrm_selector selector; /* 96 56 */ struct xfrm_lifetime_cfg lft; /* 152 64 */ struct xfrm_lifetime_cur curlft; /* 216 32 */ struct dst_entry * bundles; /* 248 4 */ __u16 family; /* 252 2 */ __u8 action; /* 254 1 */ __u8 flags; /* 255 1 */ __u8 dead; /* 256 1 */ __u8 xfrm_nr; /* 257 1 */ /* XXX 2 bytes hole, try to pack */ struct xfrm_sec_ctx * security; /* 260 4 */ struct xfrm_tmpl xfrm_vec[6]; /* 264 360 */ }; /* size: 624, sum members: 619, holes: 2, sum holes: 5 */ So lets have just one hole instead of two, by moving 'type' to just before 'action', end result: [acme@newtoy net-2.6.20]$ codiff -s /tmp/tcp.o.before net/ipv4/tcp.o /pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv4/tcp.c: struct xfrm_policy | -4 1 struct changed [acme@newtoy net-2.6.20]$ [acme@newtoy net-2.6.20]$ pahole -c 64 net/ipv4/tcp.o xfrm_policy /* /pub/scm/linux/kernel/git/acme/net-2.6.20/include/linux/security.h:67 */ struct xfrm_policy { struct xfrm_policy * next; /* 0 4 */ struct hlist_node bydst; /* 4 8 */ struct hlist_node byidx; /* 12 8 */ rwlock_t lock; /* 20 36 */ atomic_t refcnt; /* 56 4 */ struct timer_list timer; /* 60 24 */ u32 priority; /* 84 4 */ u32 index; /* 88 4 */ struct xfrm_selector selector; /* 92 56 */ struct xfrm_lifetime_cfg lft; /* 148 64 */ struct xfrm_lifetime_cur curlft; /* 212 32 */ struct dst_entry * bundles; /* 244 4 */ u16 family; /* 248 2 */ u8 type; /* 250 1 */ u8 action; /* 251 1 */ u8 flags; /* 252 1 */ u8 dead; /* 253 1 */ u8 xfrm_nr; /* 254 1 */ /* XXX 1 byte hole, try to pack */ struct xfrm_sec_ctx * security; /* 256 4 */ struct xfrm_tmpl xfrm_vec[6]; /* 260 360 */ }; /* size: 620, sum members: 619, holes: 1, sum holes: 1 */ Are there any fugly data dependencies here? None that I know. In the process changed the removed the __ prefixed types, that are just for userspace visible headers. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> |
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.. | ||
bluetooth | ||
irda | ||
netfilter | ||
sctp | ||
tc_act | ||
tipc | ||
act_api.h | ||
addrconf.h | ||
af_unix.h | ||
ah.h | ||
arp.h | ||
atmclip.h | ||
ax25.h | ||
checksum.h | ||
cipso_ipv4.h | ||
compat.h | ||
datalink.h | ||
dn_dev.h | ||
dn_fib.h | ||
dn_neigh.h | ||
dn_nsp.h | ||
dn_route.h | ||
dn.h | ||
dsfield.h | ||
dst.h | ||
esp.h | ||
fib_rules.h | ||
flow.h | ||
gen_stats.h | ||
genetlink.h | ||
icmp.h | ||
ieee80211_crypt.h | ||
ieee80211_radiotap.h | ||
ieee80211.h | ||
ieee80211softmac_wx.h | ||
ieee80211softmac.h | ||
if_inet6.h | ||
inet6_connection_sock.h | ||
inet6_hashtables.h | ||
inet_common.h | ||
inet_connection_sock.h | ||
inet_ecn.h | ||
inet_hashtables.h | ||
inet_sock.h | ||
inet_timewait_sock.h | ||
inetpeer.h | ||
ip6_checksum.h | ||
ip6_fib.h | ||
ip6_route.h | ||
ip6_tunnel.h | ||
ip_fib.h | ||
ip_mp_alg.h | ||
ip_vs.h | ||
ip.h | ||
ipcomp.h | ||
ipconfig.h | ||
ipip.h | ||
ipv6.h | ||
ipx.h | ||
iw_handler.h | ||
lapb.h | ||
llc_c_ac.h | ||
llc_c_ev.h | ||
llc_c_st.h | ||
llc_conn.h | ||
llc_if.h | ||
llc_pdu.h | ||
llc_s_ac.h | ||
llc_s_ev.h | ||
llc_s_st.h | ||
llc_sap.h | ||
llc.h | ||
mip6.h | ||
ndisc.h | ||
neighbour.h | ||
netdma.h | ||
netevent.h | ||
netlabel.h | ||
netlink.h | ||
netrom.h | ||
nexthop.h | ||
p8022.h | ||
pkt_cls.h | ||
pkt_sched.h | ||
protocol.h | ||
psnap.h | ||
raw.h | ||
rawv6.h | ||
red.h | ||
request_sock.h | ||
rose.h | ||
route.h | ||
sch_generic.h | ||
scm.h | ||
slhc_vj.h | ||
snmp.h | ||
sock.h | ||
syncppp.h | ||
tcp_ecn.h | ||
tcp_states.h | ||
tcp.h | ||
timewait_sock.h | ||
transp_v6.h | ||
udp.h | ||
udplite.h | ||
x25.h | ||
x25device.h | ||
xfrm.h |