diff options
author | Varun Wadekar <vwadekar@nvidia.com> | 2012-04-07 01:52:57 +0530 |
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committer | Varun Wadekar <vwadekar@nvidia.com> | 2012-04-07 01:52:57 +0530 |
commit | 97caf63d0c837f9b5c9f6f469979e68c0378e83f (patch) | |
tree | c6fc834bcfb66268f474324eca619db419010532 /lib/prio_tree.c | |
parent | 6a1a6f4f69adf0febfd923795b45edeff63e75ed (diff) |
Merge branch '3.4-rc1' into android-tegra-nv-3.3-rebased
Change-Id: Ib3b69ffc5ac3e07c9cc44cc49e9142088eec477e
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Diffstat (limited to 'lib/prio_tree.c')
-rw-r--r-- | lib/prio_tree.c | 156 |
1 files changed, 69 insertions, 87 deletions
diff --git a/lib/prio_tree.c b/lib/prio_tree.c index ccfd850b0dec..8d443af03b4c 100644 --- a/lib/prio_tree.c +++ b/lib/prio_tree.c @@ -85,6 +85,17 @@ static inline unsigned long prio_tree_maxindex(unsigned int bits) return index_bits_to_maxindex[bits - 1]; } +static void prio_set_parent(struct prio_tree_node *parent, + struct prio_tree_node *child, bool left) +{ + if (left) + parent->left = child; + else + parent->right = child; + + child->parent = parent; +} + /* * Extend a priority search tree so that it can store a node with heap_index * max_heap_index. In the worst case, this algorithm takes O((log n)^2). @@ -94,45 +105,32 @@ static inline unsigned long prio_tree_maxindex(unsigned int bits) static struct prio_tree_node *prio_tree_expand(struct prio_tree_root *root, struct prio_tree_node *node, unsigned long max_heap_index) { - struct prio_tree_node *first = NULL, *prev, *last = NULL; + struct prio_tree_node *prev; if (max_heap_index > prio_tree_maxindex(root->index_bits)) root->index_bits++; + prev = node; + INIT_PRIO_TREE_NODE(node); + while (max_heap_index > prio_tree_maxindex(root->index_bits)) { + struct prio_tree_node *tmp = root->prio_tree_node; + root->index_bits++; if (prio_tree_empty(root)) continue; - if (first == NULL) { - first = root->prio_tree_node; - prio_tree_remove(root, root->prio_tree_node); - INIT_PRIO_TREE_NODE(first); - last = first; - } else { - prev = last; - last = root->prio_tree_node; - prio_tree_remove(root, root->prio_tree_node); - INIT_PRIO_TREE_NODE(last); - prev->left = last; - last->parent = prev; - } - } - - INIT_PRIO_TREE_NODE(node); - - if (first) { - node->left = first; - first->parent = node; - } else - last = node; + prio_tree_remove(root, root->prio_tree_node); + INIT_PRIO_TREE_NODE(tmp); - if (!prio_tree_empty(root)) { - last->left = root->prio_tree_node; - last->left->parent = last; + prio_set_parent(prev, tmp, true); + prev = tmp; } + if (!prio_tree_empty(root)) + prio_set_parent(prev, root->prio_tree_node, true); + root->prio_tree_node = node; return node; } @@ -151,25 +149,15 @@ struct prio_tree_node *prio_tree_replace(struct prio_tree_root *root, * We can reduce root->index_bits here. However, it is complex * and does not help much to improve performance (IMO). */ - node->parent = node; root->prio_tree_node = node; - } else { - node->parent = old->parent; - if (old->parent->left == old) - old->parent->left = node; - else - old->parent->right = node; - } + } else + prio_set_parent(old->parent, node, old->parent->left == old); - if (!prio_tree_left_empty(old)) { - node->left = old->left; - old->left->parent = node; - } + if (!prio_tree_left_empty(old)) + prio_set_parent(node, old->left, true); - if (!prio_tree_right_empty(old)) { - node->right = old->right; - old->right->parent = node; - } + if (!prio_tree_right_empty(old)) + prio_set_parent(node, old->right, false); return old; } @@ -229,16 +217,14 @@ struct prio_tree_node *prio_tree_insert(struct prio_tree_root *root, if (index & mask) { if (prio_tree_right_empty(cur)) { INIT_PRIO_TREE_NODE(node); - cur->right = node; - node->parent = cur; + prio_set_parent(cur, node, false); return res; } else cur = cur->right; } else { if (prio_tree_left_empty(cur)) { INIT_PRIO_TREE_NODE(node); - cur->left = node; - node->parent = cur; + prio_set_parent(cur, node, true); return res; } else cur = cur->left; @@ -305,6 +291,40 @@ void prio_tree_remove(struct prio_tree_root *root, struct prio_tree_node *node) cur = prio_tree_replace(root, cur->parent, cur); } +static void iter_walk_down(struct prio_tree_iter *iter) +{ + iter->mask >>= 1; + if (iter->mask) { + if (iter->size_level) + iter->size_level++; + return; + } + + if (iter->size_level) { + BUG_ON(!prio_tree_left_empty(iter->cur)); + BUG_ON(!prio_tree_right_empty(iter->cur)); + iter->size_level++; + iter->mask = ULONG_MAX; + } else { + iter->size_level = 1; + iter->mask = 1UL << (BITS_PER_LONG - 1); + } +} + +static void iter_walk_up(struct prio_tree_iter *iter) +{ + if (iter->mask == ULONG_MAX) + iter->mask = 1UL; + else if (iter->size_level == 1) + iter->mask = 1UL; + else + iter->mask <<= 1; + if (iter->size_level) + iter->size_level--; + if (!iter->size_level && (iter->value & iter->mask)) + iter->value ^= iter->mask; +} + /* * Following functions help to enumerate all prio_tree_nodes in the tree that * overlap with the input interval X [radix_index, heap_index]. The enumeration @@ -323,21 +343,7 @@ static struct prio_tree_node *prio_tree_left(struct prio_tree_iter *iter, if (iter->r_index <= *h_index) { iter->cur = iter->cur->left; - iter->mask >>= 1; - if (iter->mask) { - if (iter->size_level) - iter->size_level++; - } else { - if (iter->size_level) { - BUG_ON(!prio_tree_left_empty(iter->cur)); - BUG_ON(!prio_tree_right_empty(iter->cur)); - iter->size_level++; - iter->mask = ULONG_MAX; - } else { - iter->size_level = 1; - iter->mask = 1UL << (BITS_PER_LONG - 1); - } - } + iter_walk_down(iter); return iter->cur; } @@ -364,22 +370,7 @@ static struct prio_tree_node *prio_tree_right(struct prio_tree_iter *iter, if (iter->r_index <= *h_index) { iter->cur = iter->cur->right; - iter->mask >>= 1; - iter->value = value; - if (iter->mask) { - if (iter->size_level) - iter->size_level++; - } else { - if (iter->size_level) { - BUG_ON(!prio_tree_left_empty(iter->cur)); - BUG_ON(!prio_tree_right_empty(iter->cur)); - iter->size_level++; - iter->mask = ULONG_MAX; - } else { - iter->size_level = 1; - iter->mask = 1UL << (BITS_PER_LONG - 1); - } - } + iter_walk_down(iter); return iter->cur; } @@ -389,16 +380,7 @@ static struct prio_tree_node *prio_tree_right(struct prio_tree_iter *iter, static struct prio_tree_node *prio_tree_parent(struct prio_tree_iter *iter) { iter->cur = iter->cur->parent; - if (iter->mask == ULONG_MAX) - iter->mask = 1UL; - else if (iter->size_level == 1) - iter->mask = 1UL; - else - iter->mask <<= 1; - if (iter->size_level) - iter->size_level--; - if (!iter->size_level && (iter->value & iter->mask)) - iter->value ^= iter->mask; + iter_walk_up(iter); return iter->cur; } |