From db3459d1a71d885334831cdca6646a48f5ea0483 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 3 May 2007 17:39:04 -0700 Subject: [PATCH] [IPV6]: Some cleanups in include/net/ipv6.h 1) struct ip6_flowlabel : moves 'users' field to avoid two 32bits holes for 64bit arches. Shrinks by 8 bytes sizeof(struct ip6_flowlabel) 2) ipv6_addr_cmp() and ipv6_addr_copy() dont need (void *) casts : Compiler might take into account natural alignement of in6_addr structs to emit better code for memcpy()/memcmp() Casts to (void *) force byte accesses. 3) ipv6_addr_prefix() optimization : Better to clear whole struct, as compiler can emit better code for memset(addr, 0, 16) (2 stores on x86_64), and avoid some conditional branches. # size vmlinux.after vmlinux.before text data bss dec hex filename 5262262 647612 557432 6467306 62aeea vmlinux.after 5262550 647612 557432 6467594 62b00a vmlinux.before thats 288 bytes saved. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/ipv6.h | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 2ce3941d8993..4fa5dfe886c4 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -204,9 +204,9 @@ struct ip6_flowlabel { struct ip6_flowlabel *next; __be32 label; + atomic_t users; struct in6_addr dst; struct ipv6_txoptions *opt; - atomic_t users; unsigned long linger; u8 share; u32 owner; @@ -291,7 +291,7 @@ static inline int ipv6_addr_src_scope(const struct in6_addr *addr) static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2) { - return memcmp((const void *) a1, (const void *) a2, sizeof(struct in6_addr)); + return memcmp(a1, a2, sizeof(struct in6_addr)); } static inline int @@ -308,7 +308,7 @@ ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m, static inline void ipv6_addr_copy(struct in6_addr *a1, const struct in6_addr *a2) { - memcpy((void *) a1, (const void *) a2, sizeof(struct in6_addr)); + memcpy(a1, a2, sizeof(struct in6_addr)); } static inline void ipv6_addr_prefix(struct in6_addr *pfx, @@ -319,13 +319,10 @@ static inline void ipv6_addr_prefix(struct in6_addr *pfx, int o = plen >> 3, b = plen & 0x7; + memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr)); memcpy(pfx->s6_addr, addr, o); - if (b != 0) { + if (b != 0) pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b); - o++; - } - if (o < 16) - memset(pfx->s6_addr + o, 0, 16 - o); } static inline void ipv6_addr_set(struct in6_addr *addr, -- 2.30.2