path: root/net/ipv4/fib_lookup.h
diff options
authorEric Dumazet <dada1@cosmosbay.com>2008-01-18 03:33:26 -0800
committerDavid S. Miller <davem@davemloft.net>2008-01-28 15:02:46 -0800
commita6501e080c318f8d4467679d17807f42b3a33cd5 (patch)
tree02ba4422ec6603b2bfddace52b2fabaaa6725496 /net/ipv4/fib_lookup.h
parent[FIB]: Fix rcu_dereference() abuses in fib_trie.c (diff)
[IPV4] FIB_HASH: Reduce memory needs and speedup lookups
Currently, sizeof(struct fib_alias) is 24 or 48 bytes on 32/64 bits arches. Because of SLAB_HWCACHE_ALIGN requirement, these are rounded to 32 and 64 bytes respectively. This patch moves rcu to the end of fib_alias, and conditionally defines it only for CONFIG_IP_FIB_TRIE. We also remove SLAB_HWCACHE_ALIGN requirement for fib_alias and fib_node objects because it is not necessary. (BTW SLUB currently denies it for objects smaller than cache_line_size() / 2, but not SLAB) Finally, sizeof(fib_alias) go back to 16 and 32 bytes. Then, we can embed one fib_alias on each fib_node, to favor locality. Most of the time access to the fib_alias will be free because one cache line contains both the list head (fn_alias) and (one of) the list element. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/fib_lookup.h')
1 files changed, 3 insertions, 1 deletions
diff --git a/net/ipv4/fib_lookup.h b/net/ipv4/fib_lookup.h
index 26ee66d78c18..2c1623d2768b 100644
--- a/net/ipv4/fib_lookup.h
+++ b/net/ipv4/fib_lookup.h
@@ -7,12 +7,14 @@
struct fib_alias {
struct list_head fa_list;
- struct rcu_head rcu;
struct fib_info *fa_info;
u8 fa_tos;
u8 fa_type;
u8 fa_scope;
u8 fa_state;
+ struct rcu_head rcu;
#define FA_S_ACCESSED 0x01