mirror of https://github.com/hak5/openwrt.git
346 lines
10 KiB
Diff
346 lines
10 KiB
Diff
From: Alexander Duyck <alexander.h.duyck@redhat.com>
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Date: Wed, 31 Dec 2014 10:56:31 -0800
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Subject: [PATCH] fib_trie: Move resize to after inflate/halve
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This change consists of a cut/paste of resize to behind inflate and halve
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so that I could remove the two function prototypes.
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Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
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Signed-off-by: David S. Miller <davem@davemloft.net>
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---
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--- a/net/ipv4/fib_trie.c
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+++ b/net/ipv4/fib_trie.c
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@@ -149,8 +149,6 @@ struct trie {
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static void tnode_put_child_reorg(struct tnode *tn, unsigned long i,
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struct tnode *n, int wasfull);
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static struct tnode *resize(struct trie *t, struct tnode *tn);
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-static struct tnode *inflate(struct trie *t, struct tnode *tn);
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-static struct tnode *halve(struct trie *t, struct tnode *tn);
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/* tnodes to free after resize(); protected by RTNL */
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static struct callback_head *tnode_free_head;
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static size_t tnode_free_size;
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@@ -447,161 +445,6 @@ static void put_child_root(struct tnode
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rcu_assign_pointer(t->trie, n);
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}
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-#define MAX_WORK 10
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-static struct tnode *resize(struct trie *t, struct tnode *tn)
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-{
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- struct tnode *old_tn, *n = NULL;
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- int inflate_threshold_use;
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- int halve_threshold_use;
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- int max_work;
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-
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- if (!tn)
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- return NULL;
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-
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- pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
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- tn, inflate_threshold, halve_threshold);
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-
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- /* No children */
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- if (tn->empty_children > (tnode_child_length(tn) - 1))
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- goto no_children;
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-
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- /* One child */
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- if (tn->empty_children == (tnode_child_length(tn) - 1))
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- goto one_child;
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- /*
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- * Double as long as the resulting node has a number of
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- * nonempty nodes that are above the threshold.
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- */
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-
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- /*
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- * From "Implementing a dynamic compressed trie" by Stefan Nilsson of
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- * the Helsinki University of Technology and Matti Tikkanen of Nokia
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- * Telecommunications, page 6:
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- * "A node is doubled if the ratio of non-empty children to all
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- * children in the *doubled* node is at least 'high'."
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- *
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- * 'high' in this instance is the variable 'inflate_threshold'. It
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- * is expressed as a percentage, so we multiply it with
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- * tnode_child_length() and instead of multiplying by 2 (since the
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- * child array will be doubled by inflate()) and multiplying
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- * the left-hand side by 100 (to handle the percentage thing) we
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- * multiply the left-hand side by 50.
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- *
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- * The left-hand side may look a bit weird: tnode_child_length(tn)
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- * - tn->empty_children is of course the number of non-null children
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- * in the current node. tn->full_children is the number of "full"
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- * children, that is non-null tnodes with a skip value of 0.
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- * All of those will be doubled in the resulting inflated tnode, so
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- * we just count them one extra time here.
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- *
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- * A clearer way to write this would be:
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- *
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- * to_be_doubled = tn->full_children;
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- * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children -
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- * tn->full_children;
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- *
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- * new_child_length = tnode_child_length(tn) * 2;
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- *
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- * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
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- * new_child_length;
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- * if (new_fill_factor >= inflate_threshold)
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- *
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- * ...and so on, tho it would mess up the while () loop.
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- *
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- * anyway,
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- * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
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- * inflate_threshold
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- *
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- * avoid a division:
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- * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
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- * inflate_threshold * new_child_length
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- *
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- * expand not_to_be_doubled and to_be_doubled, and shorten:
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- * 100 * (tnode_child_length(tn) - tn->empty_children +
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- * tn->full_children) >= inflate_threshold * new_child_length
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- *
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- * expand new_child_length:
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- * 100 * (tnode_child_length(tn) - tn->empty_children +
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- * tn->full_children) >=
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- * inflate_threshold * tnode_child_length(tn) * 2
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- *
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- * shorten again:
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- * 50 * (tn->full_children + tnode_child_length(tn) -
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- * tn->empty_children) >= inflate_threshold *
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- * tnode_child_length(tn)
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- *
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- */
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-
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- /* Keep root node larger */
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-
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- if (!node_parent(tn)) {
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- inflate_threshold_use = inflate_threshold_root;
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- halve_threshold_use = halve_threshold_root;
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- } else {
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- inflate_threshold_use = inflate_threshold;
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- halve_threshold_use = halve_threshold;
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- }
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-
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- max_work = MAX_WORK;
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- while ((tn->full_children > 0 && max_work-- &&
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- 50 * (tn->full_children + tnode_child_length(tn)
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- - tn->empty_children)
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- >= inflate_threshold_use * tnode_child_length(tn))) {
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-
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- old_tn = tn;
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- tn = inflate(t, tn);
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-
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- if (IS_ERR(tn)) {
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- tn = old_tn;
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-#ifdef CONFIG_IP_FIB_TRIE_STATS
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- this_cpu_inc(t->stats->resize_node_skipped);
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-#endif
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- break;
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- }
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- }
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-
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- /* Return if at least one inflate is run */
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- if (max_work != MAX_WORK)
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- return tn;
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-
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- /*
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- * Halve as long as the number of empty children in this
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- * node is above threshold.
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- */
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-
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- max_work = MAX_WORK;
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- while (tn->bits > 1 && max_work-- &&
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- 100 * (tnode_child_length(tn) - tn->empty_children) <
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- halve_threshold_use * tnode_child_length(tn)) {
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-
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- old_tn = tn;
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- tn = halve(t, tn);
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- if (IS_ERR(tn)) {
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- tn = old_tn;
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-#ifdef CONFIG_IP_FIB_TRIE_STATS
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- this_cpu_inc(t->stats->resize_node_skipped);
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-#endif
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- break;
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- }
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- }
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-
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-
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- /* Only one child remains */
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- if (tn->empty_children == (tnode_child_length(tn) - 1)) {
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- unsigned long i;
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-one_child:
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- for (i = tnode_child_length(tn); !n && i;)
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- n = tnode_get_child(tn, --i);
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-no_children:
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- /* compress one level */
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- node_set_parent(n, NULL);
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- tnode_free_safe(tn);
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- return n;
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- }
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- return tn;
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-}
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-
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-
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static void tnode_clean_free(struct tnode *tn)
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{
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struct tnode *tofree;
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@@ -804,6 +647,160 @@ nomem:
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return ERR_PTR(-ENOMEM);
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}
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+#define MAX_WORK 10
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+static struct tnode *resize(struct trie *t, struct tnode *tn)
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+{
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+ struct tnode *old_tn, *n = NULL;
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+ int inflate_threshold_use;
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+ int halve_threshold_use;
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+ int max_work;
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+
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+ if (!tn)
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+ return NULL;
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+
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+ pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
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+ tn, inflate_threshold, halve_threshold);
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+
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+ /* No children */
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+ if (tn->empty_children > (tnode_child_length(tn) - 1))
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+ goto no_children;
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+
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+ /* One child */
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+ if (tn->empty_children == (tnode_child_length(tn) - 1))
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+ goto one_child;
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+ /*
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+ * Double as long as the resulting node has a number of
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+ * nonempty nodes that are above the threshold.
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+ */
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+
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+ /*
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+ * From "Implementing a dynamic compressed trie" by Stefan Nilsson of
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+ * the Helsinki University of Technology and Matti Tikkanen of Nokia
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+ * Telecommunications, page 6:
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+ * "A node is doubled if the ratio of non-empty children to all
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+ * children in the *doubled* node is at least 'high'."
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+ *
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+ * 'high' in this instance is the variable 'inflate_threshold'. It
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+ * is expressed as a percentage, so we multiply it with
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+ * tnode_child_length() and instead of multiplying by 2 (since the
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+ * child array will be doubled by inflate()) and multiplying
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+ * the left-hand side by 100 (to handle the percentage thing) we
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+ * multiply the left-hand side by 50.
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+ *
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+ * The left-hand side may look a bit weird: tnode_child_length(tn)
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+ * - tn->empty_children is of course the number of non-null children
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+ * in the current node. tn->full_children is the number of "full"
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+ * children, that is non-null tnodes with a skip value of 0.
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+ * All of those will be doubled in the resulting inflated tnode, so
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+ * we just count them one extra time here.
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+ *
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+ * A clearer way to write this would be:
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+ *
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+ * to_be_doubled = tn->full_children;
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+ * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children -
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+ * tn->full_children;
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+ *
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+ * new_child_length = tnode_child_length(tn) * 2;
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+ *
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+ * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
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+ * new_child_length;
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+ * if (new_fill_factor >= inflate_threshold)
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+ *
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+ * ...and so on, tho it would mess up the while () loop.
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+ *
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+ * anyway,
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+ * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
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+ * inflate_threshold
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+ *
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+ * avoid a division:
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+ * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
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+ * inflate_threshold * new_child_length
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+ *
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+ * expand not_to_be_doubled and to_be_doubled, and shorten:
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+ * 100 * (tnode_child_length(tn) - tn->empty_children +
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+ * tn->full_children) >= inflate_threshold * new_child_length
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+ *
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+ * expand new_child_length:
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+ * 100 * (tnode_child_length(tn) - tn->empty_children +
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+ * tn->full_children) >=
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+ * inflate_threshold * tnode_child_length(tn) * 2
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+ *
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+ * shorten again:
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+ * 50 * (tn->full_children + tnode_child_length(tn) -
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+ * tn->empty_children) >= inflate_threshold *
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+ * tnode_child_length(tn)
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+ *
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+ */
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+
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+ /* Keep root node larger */
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+
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+ if (!node_parent(tn)) {
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+ inflate_threshold_use = inflate_threshold_root;
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+ halve_threshold_use = halve_threshold_root;
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+ } else {
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+ inflate_threshold_use = inflate_threshold;
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+ halve_threshold_use = halve_threshold;
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+ }
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+
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+ max_work = MAX_WORK;
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+ while ((tn->full_children > 0 && max_work-- &&
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+ 50 * (tn->full_children + tnode_child_length(tn)
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+ - tn->empty_children)
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+ >= inflate_threshold_use * tnode_child_length(tn))) {
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+
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+ old_tn = tn;
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+ tn = inflate(t, tn);
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+
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+ if (IS_ERR(tn)) {
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+ tn = old_tn;
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+#ifdef CONFIG_IP_FIB_TRIE_STATS
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+ this_cpu_inc(t->stats->resize_node_skipped);
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+#endif
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+ break;
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+ }
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+ }
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+
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+ /* Return if at least one inflate is run */
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+ if (max_work != MAX_WORK)
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+ return tn;
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+
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+ /*
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+ * Halve as long as the number of empty children in this
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+ * node is above threshold.
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+ */
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+
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+ max_work = MAX_WORK;
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+ while (tn->bits > 1 && max_work-- &&
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+ 100 * (tnode_child_length(tn) - tn->empty_children) <
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+ halve_threshold_use * tnode_child_length(tn)) {
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+
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+ old_tn = tn;
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+ tn = halve(t, tn);
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+ if (IS_ERR(tn)) {
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+ tn = old_tn;
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+#ifdef CONFIG_IP_FIB_TRIE_STATS
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+ this_cpu_inc(t->stats->resize_node_skipped);
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+#endif
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+ break;
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+ }
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+ }
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+
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+
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+ /* Only one child remains */
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+ if (tn->empty_children == (tnode_child_length(tn) - 1)) {
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+ unsigned long i;
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+one_child:
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+ for (i = tnode_child_length(tn); !n && i;)
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+ n = tnode_get_child(tn, --i);
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+no_children:
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+ /* compress one level */
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+ node_set_parent(n, NULL);
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+ tnode_free_safe(tn);
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+ return n;
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+ }
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+ return tn;
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+}
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+
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/* readside must use rcu_read_lock currently dump routines
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via get_fa_head and dump */
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