diff options
Diffstat (limited to 'target/linux/generic/patches-3.18/080-22-fib_trie-Add-collapse-and-should_collapse-to-resize.patch')
-rw-r--r-- | target/linux/generic/patches-3.18/080-22-fib_trie-Add-collapse-and-should_collapse-to-resize.patch | 206 |
1 files changed, 0 insertions, 206 deletions
diff --git a/target/linux/generic/patches-3.18/080-22-fib_trie-Add-collapse-and-should_collapse-to-resize.patch b/target/linux/generic/patches-3.18/080-22-fib_trie-Add-collapse-and-should_collapse-to-resize.patch deleted file mode 100644 index 19b7db7f94..0000000000 --- a/target/linux/generic/patches-3.18/080-22-fib_trie-Add-collapse-and-should_collapse-to-resize.patch +++ /dev/null @@ -1,206 +0,0 @@ -From: Alexander Duyck <alexander.h.duyck@redhat.com> -Date: Thu, 22 Jan 2015 15:51:26 -0800 -Subject: [PATCH] fib_trie: Add collapse() and should_collapse() to resize - -This patch really does two things. - -First it pulls the logic for determining if we should collapse one node out -of the tree and the actual code doing the collapse into a separate pair of -functions. This helps to make the changes to these areas more readable. - -Second it encodes the upper 32b of the empty_children value onto the -full_children value in the case of bits == KEYLENGTH. By doing this we are -able to handle the case of a 32b node where empty_children would appear to -be 0 when it was actually 1ul << 32. - -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 -@@ -83,7 +83,8 @@ - - #define MAX_STAT_DEPTH 32 - --#define KEYLENGTH (8*sizeof(t_key)) -+#define KEYLENGTH (8*sizeof(t_key)) -+#define KEY_MAX ((t_key)~0) - - typedef unsigned int t_key; - -@@ -102,8 +103,8 @@ struct tnode { - union { - /* The fields in this struct are valid if bits > 0 (TNODE) */ - struct { -- unsigned int full_children; /* KEYLENGTH bits needed */ -- unsigned int empty_children; /* KEYLENGTH bits needed */ -+ t_key empty_children; /* KEYLENGTH bits needed */ -+ t_key full_children; /* KEYLENGTH bits needed */ - struct tnode __rcu *child[0]; - }; - /* This list pointer if valid if bits == 0 (LEAF) */ -@@ -302,6 +303,16 @@ static struct tnode *tnode_alloc(size_t - return vzalloc(size); - } - -+static inline void empty_child_inc(struct tnode *n) -+{ -+ ++n->empty_children ? : ++n->full_children; -+} -+ -+static inline void empty_child_dec(struct tnode *n) -+{ -+ n->empty_children-- ? : n->full_children--; -+} -+ - static struct tnode *leaf_new(t_key key) - { - struct tnode *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL); -@@ -335,7 +346,7 @@ static struct leaf_info *leaf_info_new(i - - static struct tnode *tnode_new(t_key key, int pos, int bits) - { -- size_t sz = offsetof(struct tnode, child[1 << bits]); -+ size_t sz = offsetof(struct tnode, child[1ul << bits]); - struct tnode *tn = tnode_alloc(sz); - unsigned int shift = pos + bits; - -@@ -348,8 +359,10 @@ static struct tnode *tnode_new(t_key key - tn->pos = pos; - tn->bits = bits; - tn->key = (shift < KEYLENGTH) ? (key >> shift) << shift : 0; -- tn->full_children = 0; -- tn->empty_children = 1<<bits; -+ if (bits == KEYLENGTH) -+ tn->full_children = 1; -+ else -+ tn->empty_children = 1ul << bits; - } - - pr_debug("AT %p s=%zu %zu\n", tn, sizeof(struct tnode), -@@ -375,11 +388,11 @@ static void put_child(struct tnode *tn, - - BUG_ON(i >= tnode_child_length(tn)); - -- /* update emptyChildren */ -+ /* update emptyChildren, overflow into fullChildren */ - if (n == NULL && chi != NULL) -- tn->empty_children++; -- else if (n != NULL && chi == NULL) -- tn->empty_children--; -+ empty_child_inc(tn); -+ if (n != NULL && chi == NULL) -+ empty_child_dec(tn); - - /* update fullChildren */ - wasfull = tnode_full(tn, chi); -@@ -630,6 +643,24 @@ static int halve(struct trie *t, struct - return 0; - } - -+static void collapse(struct trie *t, struct tnode *oldtnode) -+{ -+ struct tnode *n, *tp; -+ unsigned long i; -+ -+ /* scan the tnode looking for that one child that might still exist */ -+ for (n = NULL, i = tnode_child_length(oldtnode); !n && i;) -+ n = tnode_get_child(oldtnode, --i); -+ -+ /* compress one level */ -+ tp = node_parent(oldtnode); -+ put_child_root(tp, t, oldtnode->key, n); -+ node_set_parent(n, tp); -+ -+ /* drop dead node */ -+ node_free(oldtnode); -+} -+ - static unsigned char update_suffix(struct tnode *tn) - { - unsigned char slen = tn->pos; -@@ -729,10 +760,12 @@ static bool should_inflate(const struct - - /* Keep root node larger */ - threshold *= tp ? inflate_threshold : inflate_threshold_root; -- used += tn->full_children; - used -= tn->empty_children; -+ used += tn->full_children; - -- return tn->pos && ((50 * used) >= threshold); -+ /* if bits == KEYLENGTH then pos = 0, and will fail below */ -+ -+ return (used > 1) && tn->pos && ((50 * used) >= threshold); - } - - static bool should_halve(const struct tnode *tp, const struct tnode *tn) -@@ -744,13 +777,29 @@ static bool should_halve(const struct tn - threshold *= tp ? halve_threshold : halve_threshold_root; - used -= tn->empty_children; - -- return (tn->bits > 1) && ((100 * used) < threshold); -+ /* if bits == KEYLENGTH then used = 100% on wrap, and will fail below */ -+ -+ return (used > 1) && (tn->bits > 1) && ((100 * used) < threshold); -+} -+ -+static bool should_collapse(const struct tnode *tn) -+{ -+ unsigned long used = tnode_child_length(tn); -+ -+ used -= tn->empty_children; -+ -+ /* account for bits == KEYLENGTH case */ -+ if ((tn->bits == KEYLENGTH) && tn->full_children) -+ used -= KEY_MAX; -+ -+ /* One child or none, time to drop us from the trie */ -+ return used < 2; - } - - #define MAX_WORK 10 - static void resize(struct trie *t, struct tnode *tn) - { -- struct tnode *tp = node_parent(tn), *n = NULL; -+ struct tnode *tp = node_parent(tn); - struct tnode __rcu **cptr; - int max_work = MAX_WORK; - -@@ -764,14 +813,6 @@ static void resize(struct trie *t, struc - cptr = tp ? &tp->child[get_index(tn->key, tp)] : &t->trie; - BUG_ON(tn != rtnl_dereference(*cptr)); - -- /* No children */ -- if (tn->empty_children > (tnode_child_length(tn) - 1)) -- goto no_children; -- -- /* One child */ -- if (tn->empty_children == (tnode_child_length(tn) - 1)) -- goto one_child; -- - /* Double as long as the resulting node has a number of - * nonempty nodes that are above the threshold. - */ -@@ -807,19 +848,8 @@ static void resize(struct trie *t, struc - } - - /* Only one child remains */ -- if (tn->empty_children == (tnode_child_length(tn) - 1)) { -- unsigned long i; --one_child: -- for (i = tnode_child_length(tn); !n && i;) -- n = tnode_get_child(tn, --i); --no_children: -- /* compress one level */ -- put_child_root(tp, t, tn->key, n); -- node_set_parent(n, tp); -- -- /* drop dead node */ -- tnode_free_init(tn); -- tnode_free(tn); -+ if (should_collapse(tn)) { -+ collapse(t, tn); - return; - } - |