diff options
Diffstat (limited to 'target/linux/generic/patches-3.18/080-08-fib_trie-Optimize-fib_table_insert.patch')
-rw-r--r-- | target/linux/generic/patches-3.18/080-08-fib_trie-Optimize-fib_table_insert.patch | 276 |
1 files changed, 0 insertions, 276 deletions
diff --git a/target/linux/generic/patches-3.18/080-08-fib_trie-Optimize-fib_table_insert.patch b/target/linux/generic/patches-3.18/080-08-fib_trie-Optimize-fib_table_insert.patch deleted file mode 100644 index b328d2c5d2..0000000000 --- a/target/linux/generic/patches-3.18/080-08-fib_trie-Optimize-fib_table_insert.patch +++ /dev/null @@ -1,276 +0,0 @@ -From: Alexander Duyck <alexander.h.duyck@redhat.com> -Date: Wed, 31 Dec 2014 10:56:06 -0800 -Subject: [PATCH] fib_trie: Optimize fib_table_insert - -This patch updates the fib_table_insert function to take advantage of the -changes made to improve the performance of fib_table_lookup. As a result -the code should be smaller and run faster then 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 -@@ -222,31 +222,6 @@ static inline t_key tkey_extract_bits(t_ - return 0; - } - --static inline int tkey_equals(t_key a, t_key b) --{ -- return a == b; --} -- --static inline int tkey_sub_equals(t_key a, int offset, int bits, t_key b) --{ -- if (bits == 0 || offset >= KEYLENGTH) -- return 1; -- bits = bits > KEYLENGTH ? KEYLENGTH : bits; -- return ((a ^ b) << offset) >> (KEYLENGTH - bits) == 0; --} -- --static inline int tkey_mismatch(t_key a, int offset, t_key b) --{ -- t_key diff = a ^ b; -- int i = offset; -- -- if (!diff) -- return 0; -- while ((diff << i) >> (KEYLENGTH-1) == 0) -- i++; -- return i; --} -- - /* - To understand this stuff, an understanding of keys and all their bits is - necessary. Every node in the trie has a key associated with it, but not -@@ -485,6 +460,15 @@ static void tnode_put_child_reorg(struct - rcu_assign_pointer(tn->child[i], n); - } - -+static void put_child_root(struct tnode *tp, struct trie *t, -+ t_key key, struct tnode *n) -+{ -+ if (tp) -+ put_child(tp, get_index(key, tp), n); -+ else -+ rcu_assign_pointer(t->trie, n); -+} -+ - #define MAX_WORK 10 - static struct tnode *resize(struct trie *t, struct tnode *tn) - { -@@ -959,138 +943,100 @@ static void trie_rebalance(struct trie * - - static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen) - { -- int pos, newpos; -- struct tnode *tp = NULL, *tn = NULL; -- struct tnode *n; -- struct tnode *l; -- int missbit; - struct list_head *fa_head = NULL; -+ struct tnode *l, *n, *tp = NULL; - struct leaf_info *li; -- t_key cindex; - -- pos = 0; -+ li = leaf_info_new(plen); -+ if (!li) -+ return NULL; -+ fa_head = &li->falh; -+ - n = rtnl_dereference(t->trie); - - /* If we point to NULL, stop. Either the tree is empty and we should - * just put a new leaf in if, or we have reached an empty child slot, - * and we should just put our new leaf in that. -- * If we point to a T_TNODE, check if it matches our key. Note that -- * a T_TNODE might be skipping any number of bits - its 'pos' need -- * not be the parent's 'pos'+'bits'! -- * -- * If it does match the current key, get pos/bits from it, extract -- * the index from our key, push the T_TNODE and walk the tree. -- * -- * If it doesn't, we have to replace it with a new T_TNODE. - * -- * If we point to a T_LEAF, it might or might not have the same key -- * as we do. If it does, just change the value, update the T_LEAF's -- * value, and return it. -- * If it doesn't, we need to replace it with a T_TNODE. -+ * If we hit a node with a key that does't match then we should stop -+ * and create a new tnode to replace that node and insert ourselves -+ * and the other node into the new tnode. - */ -+ while (n) { -+ unsigned long index = get_index(key, n); - -- while (n && IS_TNODE(n)) { -- if (tkey_sub_equals(n->key, pos, n->pos-pos, key)) { -- tp = n; -- pos = n->pos + n->bits; -- n = tnode_get_child(n, -- tkey_extract_bits(key, -- n->pos, -- n->bits)); -- -- BUG_ON(n && node_parent(n) != tp); -- } else -+ /* 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 prefix. 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 child index -+ * else -+ * we have a mismatch in skip bits and failed -+ */ -+ if (index >> n->bits) - break; -- } -- -- /* -- * n ----> NULL, LEAF or TNODE -- * -- * tp is n's (parent) ----> NULL or TNODE -- */ - -- BUG_ON(tp && IS_LEAF(tp)); -- -- /* Case 1: n is a leaf. Compare prefixes */ -- -- if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) { -- li = leaf_info_new(plen); -- -- if (!li) -- return NULL; -+ /* we have found a leaf. Prefixes have already been compared */ -+ if (IS_LEAF(n)) { -+ /* Case 1: n is a leaf, and prefixes match*/ -+ insert_leaf_info(&n->list, li); -+ return fa_head; -+ } - -- fa_head = &li->falh; -- insert_leaf_info(&n->list, li); -- goto done; -+ tp = n; -+ n = rcu_dereference_rtnl(n->child[index]); - } -- l = leaf_new(key); -- -- if (!l) -- return NULL; - -- li = leaf_info_new(plen); -- -- if (!li) { -- node_free(l); -+ l = leaf_new(key); -+ if (!l) { -+ free_leaf_info(li); - return NULL; - } - -- fa_head = &li->falh; - insert_leaf_info(&l->list, li); - -- if (t->trie && n == NULL) { -- /* Case 2: n is NULL, and will just insert a new leaf */ -- -- node_set_parent(l, tp); -- -- cindex = tkey_extract_bits(key, tp->pos, tp->bits); -- put_child(tp, cindex, l); -- } else { -- /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */ -- /* -- * Add a new tnode here -- * first tnode need some special handling -- */ -+ /* Case 2: n is a LEAF or a TNODE and the key doesn't match. -+ * -+ * Add a new tnode here -+ * first tnode need some special handling -+ * leaves us in position for handling as case 3 -+ */ -+ if (n) { -+ struct tnode *tn; -+ int newpos; - -- if (n) { -- pos = tp ? tp->pos+tp->bits : 0; -- newpos = tkey_mismatch(key, pos, n->key); -- tn = tnode_new(n->key, newpos, 1); -- } else { -- newpos = 0; -- tn = tnode_new(key, newpos, 1); /* First tnode */ -- } -+ newpos = KEYLENGTH - __fls(n->key ^ key) - 1; - -+ tn = tnode_new(key, newpos, 1); - if (!tn) { - free_leaf_info(li); - node_free(l); - return NULL; - } - -- node_set_parent(tn, tp); -- -- missbit = tkey_extract_bits(key, newpos, 1); -- put_child(tn, missbit, l); -- put_child(tn, 1-missbit, n); -- -- if (tp) { -- cindex = tkey_extract_bits(key, tp->pos, tp->bits); -- put_child(tp, cindex, tn); -- } else { -- rcu_assign_pointer(t->trie, tn); -- } -+ /* initialize routes out of node */ -+ NODE_INIT_PARENT(tn, tp); -+ put_child(tn, get_index(key, tn) ^ 1, n); -+ -+ /* start adding routes into the node */ -+ put_child_root(tp, t, key, tn); -+ node_set_parent(n, tn); - -+ /* parent now has a NULL spot where the leaf can go */ - tp = tn; - } - -- if (tp && tp->pos + tp->bits > 32) -- pr_warn("fib_trie tp=%p pos=%d, bits=%d, key=%0x plen=%d\n", -- tp, tp->pos, tp->bits, key, plen); -- -- /* Rebalance the trie */ -+ /* Case 3: n is NULL, and will just insert a new leaf */ -+ if (tp) { -+ NODE_INIT_PARENT(l, tp); -+ put_child(tp, get_index(key, tp), l); -+ trie_rebalance(t, tp); -+ } else { -+ rcu_assign_pointer(t->trie, l); -+ } - -- trie_rebalance(t, tp); --done: - return fa_head; - } - -@@ -1470,11 +1416,11 @@ static void trie_leaf_remove(struct trie - pr_debug("entering trie_leaf_remove(%p)\n", l); - - if (tp) { -- t_key cindex = tkey_extract_bits(l->key, tp->pos, tp->bits); -- put_child(tp, cindex, NULL); -+ put_child(tp, get_index(l->key, tp), NULL); - trie_rebalance(t, tp); -- } else -+ } else { - RCU_INIT_POINTER(t->trie, NULL); -+ } - - node_free(l); - } |