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Diffstat (limited to 'target/linux/generic/pending-3.18/080-16-fib_trie-inflate-halve-nodes-in-a-more-RCU-friendly-.patch')
-rw-r--r--target/linux/generic/pending-3.18/080-16-fib_trie-inflate-halve-nodes-in-a-more-RCU-friendly-.patch345
1 files changed, 0 insertions, 345 deletions
diff --git a/target/linux/generic/pending-3.18/080-16-fib_trie-inflate-halve-nodes-in-a-more-RCU-friendly-.patch b/target/linux/generic/pending-3.18/080-16-fib_trie-inflate-halve-nodes-in-a-more-RCU-friendly-.patch
deleted file mode 100644
index d6b600c5dd..0000000000
--- a/target/linux/generic/pending-3.18/080-16-fib_trie-inflate-halve-nodes-in-a-more-RCU-friendly-.patch
+++ /dev/null
@@ -1,345 +0,0 @@
-From: Alexander Duyck <alexander.h.duyck@redhat.com>
-Date: Wed, 31 Dec 2014 10:56:55 -0800
-Subject: [PATCH] fib_trie: inflate/halve nodes in a more RCU friendly
- way
-
-This change pulls the node_set_parent functionality out of put_child_reorg
-and instead leaves that to the function to take care of as well. By doing
-this we can fully construct the new cluster of tnodes and all of the
-pointers out of it before we start routing pointers into it.
-
-I am suspecting this will likely fix some concurency issues though I don't
-have a good test to show as such.
-
-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
-@@ -391,8 +391,6 @@ static void put_child(struct tnode *tn,
- else if (!wasfull && isfull)
- tn->full_children++;
-
-- node_set_parent(n, tn);
--
- rcu_assign_pointer(tn->child[i], n);
- }
-
-@@ -436,10 +434,8 @@ static void tnode_free(struct tnode *tn)
-
- static int inflate(struct trie *t, struct tnode *oldtnode)
- {
-- unsigned long olen = tnode_child_length(oldtnode);
-- struct tnode *tp = node_parent(oldtnode);
-- struct tnode *tn;
-- unsigned long i;
-+ struct tnode *inode, *node0, *node1, *tn, *tp;
-+ unsigned long i, j, k;
- t_key m;
-
- pr_debug("In inflate\n");
-@@ -448,43 +444,13 @@ static int inflate(struct trie *t, struc
- if (!tn)
- return -ENOMEM;
-
-- /*
-- * Preallocate and store tnodes before the actual work so we
-- * don't get into an inconsistent state if memory allocation
-- * fails. In case of failure we return the oldnode and inflate
-- * of tnode is ignored.
-+ /* Assemble all of the pointers in our cluster, in this case that
-+ * represents all of the pointers out of our allocated nodes that
-+ * point to existing tnodes and the links between our allocated
-+ * nodes.
- */
-- for (i = 0, m = 1u << tn->pos; i < olen; i++) {
-- struct tnode *inode = tnode_get_child(oldtnode, i);
--
-- if (tnode_full(oldtnode, inode) && (inode->bits > 1)) {
-- struct tnode *left, *right;
--
-- left = tnode_new(inode->key & ~m, inode->pos,
-- inode->bits - 1);
-- if (!left)
-- goto nomem;
-- tnode_free_append(tn, left);
--
-- right = tnode_new(inode->key | m, inode->pos,
-- inode->bits - 1);
--
-- if (!right)
-- goto nomem;
-- tnode_free_append(tn, right);
--
-- put_child(tn, 2*i, left);
-- put_child(tn, 2*i+1, right);
-- }
-- }
--
-- /* prepare oldtnode to be freed */
-- tnode_free_init(oldtnode);
--
-- for (i = 0; i < olen; i++) {
-- struct tnode *inode = tnode_get_child(oldtnode, i);
-- struct tnode *left, *right;
-- unsigned long size, j;
-+ for (i = tnode_child_length(oldtnode), m = 1u << tn->pos; i;) {
-+ inode = tnode_get_child(oldtnode, --i);
-
- /* An empty child */
- if (inode == NULL)
-@@ -496,65 +462,99 @@ static int inflate(struct trie *t, struc
- continue;
- }
-
-- /* drop the node in the old tnode free list */
-- tnode_free_append(oldtnode, inode);
--
- /* An internal node with two children */
- if (inode->bits == 1) {
-- put_child(tn, 2*i, rtnl_dereference(inode->child[0]));
-- put_child(tn, 2*i+1, rtnl_dereference(inode->child[1]));
-+ put_child(tn, 2 * i + 1, tnode_get_child(inode, 1));
-+ put_child(tn, 2 * i, tnode_get_child(inode, 0));
- continue;
- }
-
-- /* An internal node with more than two children */
--
- /* We will replace this node 'inode' with two new
-- * ones, 'left' and 'right', each with half of the
-+ * ones, 'node0' and 'node1', each with half of the
- * original children. The two new nodes will have
- * a position one bit further down the key and this
- * means that the "significant" part of their keys
- * (see the discussion near the top of this file)
- * will differ by one bit, which will be "0" in
-- * left's key and "1" in right's key. Since we are
-+ * node0's key and "1" in node1's key. Since we are
- * moving the key position by one step, the bit that
- * we are moving away from - the bit at position
-- * (inode->pos) - is the one that will differ between
-- * left and right. So... we synthesize that bit in the
-- * two new keys.
-- * The mask 'm' below will be a single "one" bit at
-- * the position (inode->pos)
-+ * (tn->pos) - is the one that will differ between
-+ * node0 and node1. So... we synthesize that bit in the
-+ * two new keys.
- */
-+ node1 = tnode_new(inode->key | m, inode->pos, inode->bits - 1);
-+ if (!node1)
-+ goto nomem;
-+ tnode_free_append(tn, node1);
-+
-+ node0 = tnode_new(inode->key & ~m, inode->pos, inode->bits - 1);
-+ if (!node0)
-+ goto nomem;
-+ tnode_free_append(tn, node0);
-+
-+ /* populate child pointers in new nodes */
-+ for (k = tnode_child_length(inode), j = k / 2; j;) {
-+ put_child(node1, --j, tnode_get_child(inode, --k));
-+ put_child(node0, j, tnode_get_child(inode, j));
-+ put_child(node1, --j, tnode_get_child(inode, --k));
-+ put_child(node0, j, tnode_get_child(inode, j));
-+ }
-+
-+ /* link new nodes to parent */
-+ NODE_INIT_PARENT(node1, tn);
-+ NODE_INIT_PARENT(node0, tn);
-+
-+ /* link parent to nodes */
-+ put_child(tn, 2 * i + 1, node1);
-+ put_child(tn, 2 * i, node0);
-+ }
-+
-+ /* setup the parent pointer into and out of this node */
-+ tp = node_parent(oldtnode);
-+ NODE_INIT_PARENT(tn, tp);
-+ put_child_root(tp, t, tn->key, tn);
-
-- /* Use the old key, but set the new significant
-- * bit to zero.
-- */
-+ /* prepare oldtnode to be freed */
-+ tnode_free_init(oldtnode);
-
-- left = tnode_get_child(tn, 2*i);
-- put_child(tn, 2*i, NULL);
-+ /* update all child nodes parent pointers to route to us */
-+ for (i = tnode_child_length(oldtnode); i;) {
-+ inode = tnode_get_child(oldtnode, --i);
-
-- BUG_ON(!left);
-+ /* A leaf or an internal node with skipped bits */
-+ if (!tnode_full(oldtnode, inode)) {
-+ node_set_parent(inode, tn);
-+ continue;
-+ }
-
-- right = tnode_get_child(tn, 2*i+1);
-- put_child(tn, 2*i+1, NULL);
-+ /* drop the node in the old tnode free list */
-+ tnode_free_append(oldtnode, inode);
-
-- BUG_ON(!right);
-+ /* fetch new nodes */
-+ node1 = tnode_get_child(tn, 2 * i + 1);
-+ node0 = tnode_get_child(tn, 2 * i);
-
-- size = tnode_child_length(left);
-- for (j = 0; j < size; j++) {
-- put_child(left, j, rtnl_dereference(inode->child[j]));
-- put_child(right, j, rtnl_dereference(inode->child[j + size]));
-+ /* bits == 1 then node0 and node1 represent inode's children */
-+ if (inode->bits == 1) {
-+ node_set_parent(node1, tn);
-+ node_set_parent(node0, tn);
-+ continue;
- }
-
-- put_child(tn, 2 * i, left);
-- put_child(tn, 2 * i + 1, right);
-+ /* update parent pointers in child node's children */
-+ for (k = tnode_child_length(inode), j = k / 2; j;) {
-+ node_set_parent(tnode_get_child(inode, --k), node1);
-+ node_set_parent(tnode_get_child(inode, --j), node0);
-+ node_set_parent(tnode_get_child(inode, --k), node1);
-+ node_set_parent(tnode_get_child(inode, --j), node0);
-+ }
-
- /* resize child nodes */
-- resize(t, left);
-- resize(t, right);
-+ resize(t, node1);
-+ resize(t, node0);
- }
-
-- put_child_root(tp, t, tn->key, tn);
--
- /* we completed without error, prepare to free old node */
- tnode_free(oldtnode);
- return 0;
-@@ -566,10 +566,8 @@ nomem:
-
- static int halve(struct trie *t, struct tnode *oldtnode)
- {
-- unsigned long olen = tnode_child_length(oldtnode);
-- struct tnode *tp = node_parent(oldtnode);
-- struct tnode *tn, *left, *right;
-- int i;
-+ struct tnode *tn, *tp, *inode, *node0, *node1;
-+ unsigned long i;
-
- pr_debug("In halve\n");
-
-@@ -577,68 +575,64 @@ static int halve(struct trie *t, struct
- if (!tn)
- return -ENOMEM;
-
-- /*
-- * Preallocate and store tnodes before the actual work so we
-- * don't get into an inconsistent state if memory allocation
-- * fails. In case of failure we return the oldnode and halve
-- * of tnode is ignored.
-+ /* Assemble all of the pointers in our cluster, in this case that
-+ * represents all of the pointers out of our allocated nodes that
-+ * point to existing tnodes and the links between our allocated
-+ * nodes.
- */
-+ for (i = tnode_child_length(oldtnode); i;) {
-+ node1 = tnode_get_child(oldtnode, --i);
-+ node0 = tnode_get_child(oldtnode, --i);
-
-- for (i = 0; i < olen; i += 2) {
-- left = tnode_get_child(oldtnode, i);
-- right = tnode_get_child(oldtnode, i+1);
-+ /* At least one of the children is empty */
-+ if (!node1 || !node0) {
-+ put_child(tn, i / 2, node1 ? : node0);
-+ continue;
-+ }
-
- /* Two nonempty children */
-- if (left && right) {
-- struct tnode *newn;
--
-- newn = tnode_new(left->key, oldtnode->pos, 1);
-- if (!newn) {
-- tnode_free(tn);
-- return -ENOMEM;
-- }
-- tnode_free_append(tn, newn);
--
-- put_child(tn, i/2, newn);
-+ inode = tnode_new(node0->key, oldtnode->pos, 1);
-+ if (!inode) {
-+ tnode_free(tn);
-+ return -ENOMEM;
- }
-+ tnode_free_append(tn, inode);
-
-+ /* initialize pointers out of node */
-+ put_child(inode, 1, node1);
-+ put_child(inode, 0, node0);
-+ NODE_INIT_PARENT(inode, tn);
-+
-+ /* link parent to node */
-+ put_child(tn, i / 2, inode);
- }
-
-+ /* setup the parent pointer out of and back into this node */
-+ tp = node_parent(oldtnode);
-+ NODE_INIT_PARENT(tn, tp);
-+ put_child_root(tp, t, tn->key, tn);
-+
- /* prepare oldtnode to be freed */
- tnode_free_init(oldtnode);
-
-- for (i = 0; i < olen; i += 2) {
-- struct tnode *newBinNode;
--
-- left = tnode_get_child(oldtnode, i);
-- right = tnode_get_child(oldtnode, i+1);
--
-- /* At least one of the children is empty */
-- if (left == NULL) {
-- if (right == NULL) /* Both are empty */
-- continue;
-- put_child(tn, i/2, right);
-- continue;
-- }
--
-- if (right == NULL) {
-- put_child(tn, i/2, left);
-+ /* update all of the child parent pointers */
-+ for (i = tnode_child_length(tn); i;) {
-+ inode = tnode_get_child(tn, --i);
-+
-+ /* only new tnodes will be considered "full" nodes */
-+ if (!tnode_full(tn, inode)) {
-+ node_set_parent(inode, tn);
- continue;
- }
-
- /* Two nonempty children */
-- newBinNode = tnode_get_child(tn, i/2);
-- put_child(newBinNode, 0, left);
-- put_child(newBinNode, 1, right);
--
-- put_child(tn, i / 2, newBinNode);
-+ node_set_parent(tnode_get_child(inode, 1), inode);
-+ node_set_parent(tnode_get_child(inode, 0), inode);
-
- /* resize child node */
-- resize(t, newBinNode);
-+ resize(t, inode);
- }
-
-- put_child_root(tp, t, tn->key, tn);
--
- /* all pointers should be clean so we are done */
- tnode_free(oldtnode);
-
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