diff options
Diffstat (limited to 'target/linux/generic/patches-3.18/080-07-fib_trie-Optimize-fib_find_node.patch')
| -rw-r--r-- | target/linux/generic/patches-3.18/080-07-fib_trie-Optimize-fib_find_node.patch | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/target/linux/generic/patches-3.18/080-07-fib_trie-Optimize-fib_find_node.patch b/target/linux/generic/patches-3.18/080-07-fib_trie-Optimize-fib_find_node.patch new file mode 100644 index 0000000..0193f75 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-07-fib_trie-Optimize-fib_find_node.patch @@ -0,0 +1,64 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:56:00 -0800 +Subject: [PATCH] fib_trie: Optimize fib_find_node + +This patch makes use of the same features I made use of for +fib_table_lookup to streamline fib_find_node. The resultant code should be +smaller and run faster than the original. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -892,28 +892,34 @@ static void insert_leaf_info(struct hlis + } + + /* rcu_read_lock needs to be hold by caller from readside */ +- + static struct tnode *fib_find_node(struct trie *t, u32 key) + { + struct tnode *n = rcu_dereference_rtnl(t->trie); +- int pos = 0; + +- while (n && IS_TNODE(n)) { +- if (tkey_sub_equals(n->key, pos, n->pos-pos, key)) { +- pos = n->pos + n->bits; +- n = tnode_get_child_rcu(n, +- tkey_extract_bits(key, +- n->pos, +- n->bits)); +- } else ++ while (n) { ++ unsigned long index = get_index(key, n); ++ ++ /* This bit of code is a bit tricky but it combines multiple ++ * checks into a single check. The prefix consists of the ++ * prefix plus zeros for the bits in the cindex. The index ++ * is the difference between the key and this value. From ++ * this we can actually derive several pieces of data. ++ * if !(index >> bits) ++ * we know the value is cindex ++ * else ++ * we have a mismatch in skip bits and failed ++ */ ++ if (index >> n->bits) ++ return NULL; ++ ++ /* we have found a leaf. Prefixes have already been compared */ ++ if (IS_LEAF(n)) + break; +- } +- /* Case we have found a leaf. Compare prefixes */ + +- if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) +- return n; ++ n = rcu_dereference_rtnl(n->child[index]); ++ } + +- return NULL; ++ return n; + } + + static void trie_rebalance(struct trie *t, struct tnode *tn) |