Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0794935e authored by Patrick McHardy's avatar Patrick McHardy Committed by David S. Miller
Browse files

[NETFILTER]: nf_conntrack: optimize hash_conntrack() 



Avoid calling jhash three times and hash the entire tuple in one go.

  __hash_conntrack | -485 # 760 -> 275, # inlines: 3 -> 1, size inlines: 717 -> 252
 1 function changed, 485 bytes removed

Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 380517de

net/netfilter/nf_conntrack_core.c

+11 −7
Original line number Diff line number Diff line
@@ -73,15 +73,19 @@ static unsigned int nf_conntrack_hash_rnd; 
static u_int32_t __hash_conntrack(const struct nf_conntrack_tuple *tuple,

				  unsigned int size, unsigned int rnd)

{

	unsigned int a, b;

	unsigned int n;

	u_int32_t h;



	a = jhash2(tuple->src.u3.all, ARRAY_SIZE(tuple->src.u3.all),

		   (tuple->src.l3num << 16) | tuple->dst.protonum);

	b = jhash2(tuple->dst.u3.all, ARRAY_SIZE(tuple->dst.u3.all),

		   ((__force __u16)tuple->src.u.all << 16) |

		    (__force __u16)tuple->dst.u.all);

	/* The direction must be ignored, so we hash everything up to the

	 * destination ports (which is a multiple of 4) and treat the last

	 * three bytes manually.

	 */

	n = (sizeof(tuple->src) + sizeof(tuple->dst.u3)) / sizeof(u32);

	h = jhash2((u32 *)tuple, n,

		   rnd ^ (((__force __u16)tuple->dst.u.all << 16) |

			  tuple->dst.protonum));



	return ((u64)jhash_2words(a, b, rnd) * size) >> 32;

	return ((u64)h * size) >> 32;

}



static inline u_int32_t hash_conntrack(const struct nf_conntrack_tuple *tuple)