[XFRM] IPV6: Optimize xfrm6_input_addr().

| % size old/net/ipv6/xfrm6_input.o new/net/ipv6/xfrm6_input.o
|    text	   data	    bss	    dec	    hex	filename
|    1026	      0	      0	   1026	    402	old/net/ipv6/xfrm6_input.o
|     947	      0	      0	    947	    3b3	new/net/ipv6/xfrm6_input.o

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

1 files changed, 14 insertions, 41 deletions

diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index a4714d76ae6b..a71c7ddcb41e 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -59,9 +59,6 @@ int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
                      xfrm_address_t *saddr, u8 proto)
 {
         struct xfrm_state *x = NULL;
-        int wildcard = 0;
-        xfrm_address_t *xany;
-        int nh = 0;
         int i = 0;
 
         /* Allocate new secpath or COW existing one. */
@@ -83,10 +80,9 @@ int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
                 goto drop;
         }
 
-        xany = (xfrm_address_t *)&in6addr_any;
-
         for (i = 0; i < 3; i++) {
                 xfrm_address_t *dst, *src;
+
                 switch (i) {
                 case 0:
                         dst = daddr;
@@ -94,16 +90,13 @@ int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
                         break;
                 case 1:
                         /* lookup state with wild-card source address */
-                        wildcard = 1;
                         dst = daddr;
-                        src = xany;
+                        src = (xfrm_address_t *)&in6addr_any;
                         break;
-                case 2:
                 default:
                         /* lookup state with wild-card addresses */
-                        wildcard = 1; /* XXX */
-                        dst = xany;
-                        src = xany;
+                        dst = (xfrm_address_t *)&in6addr_any;
+                        src = (xfrm_address_t *)&in6addr_any;
                         break;
                 }
 
@@ -113,39 +106,19 @@ int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
 
                 spin_lock(&x->lock);
 
-                if (wildcard) {
-                        if ((x->props.flags & XFRM_STATE_WILDRECV) == 0) {
-                                spin_unlock(&x->lock);
-                                xfrm_state_put(x);
-                                x = NULL;
-                                continue;
-                        }
-                }
-
-                if (unlikely(x->km.state != XFRM_STATE_VALID)) {
+                if ((!i || (x->props.flags & XFRM_STATE_WILDRECV)) &&
+                    likely(x->km.state == XFRM_STATE_VALID) &&
+                    !xfrm_state_check_expire(x)) {
                         spin_unlock(&x->lock);
-                        xfrm_state_put(x);
-                        x = NULL;
-                        continue;
-                }
-                if (xfrm_state_check_expire(x)) {
+                        if (x->type->input(x, skb) > 0) {
+                                /* found a valid state */
+                                break;
+                        }
+                } else
                         spin_unlock(&x->lock);
-                        xfrm_state_put(x);
-                        x = NULL;
-                        continue;
-                }
-
-                spin_unlock(&x->lock);
-
-                nh = x->type->input(x, skb);
-                if (nh <= 0) {
-                        xfrm_state_put(x);
-                        x = NULL;
-                        continue;
-                }
 
-                /* Found a state */
-                break;
+                xfrm_state_put(x);
+                x = NULL;
         }
 
         if (!x) {