functions with the user provided augmentation callback when inserting
and erasing nodes.
+C files implementing augmented rbtree manipulation must include
+<linux/rbtree_augmented.h> instead of <linus/rbtree.h>. Note that
+linux/rbtree_augmented.h exposes some rbtree implementations details
+you are not expected to rely on; please stick to the documented APIs
+there and do not include <linux/rbtree_augmented.h> from header files
+either so as to minimize chances of your users accidentally relying on
+such implementation details.
+
On insertion, the user must update the augmented information on the path
leading to the inserted node, then call rb_link_node() as usual and
rb_augment_inserted() instead of the usual rb_insert_color() call.
subtree to a newly assigned subtree root AND recomputes the augmented
information for the former subtree root.
+The compiled code for rb_erase_augmented() may inline the propagation and
+copy callbacks, which results in a large function, so each augmented rbtree
+user should have a single rb_erase_augmented() call site in order to limit
+compiled code size.
+
Sample usage:
#include <linux/debugfs.h>
#include <linux/kernel.h>
#include <linux/module.h>
-#include <linux/rbtree.h>
+#include <linux/rbtree_augmented.h>
#include <linux/sched.h>
#include <linux/gfp.h>
include/linux/interval_tree_tmpl.h
*/
+#include <linux/rbtree_augmented.h>
+
/*
* Template for implementing interval trees
*
return max;
}
-static void IT(augment_propagate)(struct rb_node *rb, struct rb_node *stop)
+static inline void
+IT(augment_propagate)(struct rb_node *rb, struct rb_node *stop)
{
while (rb != stop) {
ITSTRUCT *node = rb_entry(rb, ITSTRUCT, ITRB);
}
}
-static void IT(augment_copy)(struct rb_node *rb_old, struct rb_node *rb_new)
+static inline void
+IT(augment_copy)(struct rb_node *rb_old, struct rb_node *rb_new)
{
ITSTRUCT *old = rb_entry(rb_old, ITSTRUCT, ITRB);
ITSTRUCT *new = rb_entry(rb_new, ITSTRUCT, ITRB);
extern void rb_erase(struct rb_node *, struct rb_root *);
-struct rb_augment_callbacks {
- void (*propagate)(struct rb_node *node, struct rb_node *stop);
- void (*copy)(struct rb_node *old, struct rb_node *new);
- void (*rotate)(struct rb_node *old, struct rb_node *new);
-};
-
-extern void __rb_insert_augmented(struct rb_node *node, struct rb_root *root,
- void (*augment_rotate)(struct rb_node *old, struct rb_node *new));
-extern void rb_erase_augmented(struct rb_node *node, struct rb_root *root,
- const struct rb_augment_callbacks *augment);
-static inline void
-rb_insert_augmented(struct rb_node *node, struct rb_root *root,
- const struct rb_augment_callbacks *augment)
-{
- __rb_insert_augmented(node, root, augment->rotate);
-}
-
-#define RB_DECLARE_CALLBACKS(rbstatic, rbname, rbstruct, rbfield, \
- rbtype, rbaugmented, rbcompute) \
-static void rbname ## _propagate(struct rb_node *rb, struct rb_node *stop) \
-{ \
- while (rb != stop) { \
- rbstruct *node = rb_entry(rb, rbstruct, rbfield); \
- rbtype augmented = rbcompute(node); \
- if (node->rbaugmented == augmented) \
- break; \
- node->rbaugmented = augmented; \
- rb = rb_parent(&node->rbfield); \
- } \
-} \
-static void rbname ## _copy(struct rb_node *rb_old, struct rb_node *rb_new) \
-{ \
- rbstruct *old = rb_entry(rb_old, rbstruct, rbfield); \
- rbstruct *new = rb_entry(rb_new, rbstruct, rbfield); \
- new->rbaugmented = old->rbaugmented; \
-} \
-static void rbname ## _rotate(struct rb_node *rb_old, struct rb_node *rb_new) \
-{ \
- rbstruct *old = rb_entry(rb_old, rbstruct, rbfield); \
- rbstruct *new = rb_entry(rb_new, rbstruct, rbfield); \
- new->rbaugmented = old->rbaugmented; \
- old->rbaugmented = rbcompute(old); \
-} \
-rbstatic const struct rb_augment_callbacks rbname = { \
- rbname ## _propagate, rbname ## _copy, rbname ## _rotate \
-};
-
-
/* Find logical next and previous nodes in a tree */
extern struct rb_node *rb_next(const struct rb_node *);
extern struct rb_node *rb_prev(const struct rb_node *);
--- /dev/null
+/*
+ Red Black Trees
+ (C) 1999 Andrea Arcangeli <andrea@suse.de>
+ (C) 2002 David Woodhouse <dwmw2@infradead.org>
+ (C) 2012 Michel Lespinasse <walken@google.com>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ linux/include/linux/rbtree_augmented.h
+*/
+
+#ifndef _LINUX_RBTREE_AUGMENTED_H
+#define _LINUX_RBTREE_AUGMENTED_H
+
+#include <linux/rbtree.h>
+
+/*
+ * Please note - only struct rb_augment_callbacks and the prototypes for
+ * rb_insert_augmented() and rb_erase_augmented() are intended to be public.
+ * The rest are implementation details you are not expected to depend on.
+ *
+ * See Documentation/rbtree.txt for documentation and samples.
+ */
+
+struct rb_augment_callbacks {
+ void (*propagate)(struct rb_node *node, struct rb_node *stop);
+ void (*copy)(struct rb_node *old, struct rb_node *new);
+ void (*rotate)(struct rb_node *old, struct rb_node *new);
+};
+
+extern void __rb_insert_augmented(struct rb_node *node, struct rb_root *root,
+ void (*augment_rotate)(struct rb_node *old, struct rb_node *new));
+static inline void
+rb_insert_augmented(struct rb_node *node, struct rb_root *root,
+ const struct rb_augment_callbacks *augment)
+{
+ __rb_insert_augmented(node, root, augment->rotate);
+}
+
+#define RB_DECLARE_CALLBACKS(rbstatic, rbname, rbstruct, rbfield, \
+ rbtype, rbaugmented, rbcompute) \
+static inline void \
+rbname ## _propagate(struct rb_node *rb, struct rb_node *stop) \
+{ \
+ while (rb != stop) { \
+ rbstruct *node = rb_entry(rb, rbstruct, rbfield); \
+ rbtype augmented = rbcompute(node); \
+ if (node->rbaugmented == augmented) \
+ break; \
+ node->rbaugmented = augmented; \
+ rb = rb_parent(&node->rbfield); \
+ } \
+} \
+static inline void \
+rbname ## _copy(struct rb_node *rb_old, struct rb_node *rb_new) \
+{ \
+ rbstruct *old = rb_entry(rb_old, rbstruct, rbfield); \
+ rbstruct *new = rb_entry(rb_new, rbstruct, rbfield); \
+ new->rbaugmented = old->rbaugmented; \
+} \
+static void \
+rbname ## _rotate(struct rb_node *rb_old, struct rb_node *rb_new) \
+{ \
+ rbstruct *old = rb_entry(rb_old, rbstruct, rbfield); \
+ rbstruct *new = rb_entry(rb_new, rbstruct, rbfield); \
+ new->rbaugmented = old->rbaugmented; \
+ old->rbaugmented = rbcompute(old); \
+} \
+rbstatic const struct rb_augment_callbacks rbname = { \
+ rbname ## _propagate, rbname ## _copy, rbname ## _rotate \
+};
+
+
+#define RB_RED 0
+#define RB_BLACK 1
+
+#define __rb_parent(pc) ((struct rb_node *)(pc & ~3))
+
+#define __rb_color(pc) ((pc) & 1)
+#define __rb_is_black(pc) __rb_color(pc)
+#define __rb_is_red(pc) (!__rb_color(pc))
+#define rb_color(rb) __rb_color((rb)->__rb_parent_color)
+#define rb_is_red(rb) __rb_is_red((rb)->__rb_parent_color)
+#define rb_is_black(rb) __rb_is_black((rb)->__rb_parent_color)
+
+static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
+{
+ rb->__rb_parent_color = rb_color(rb) | (unsigned long)p;
+}
+
+static inline void rb_set_parent_color(struct rb_node *rb,
+ struct rb_node *p, int color)
+{
+ rb->__rb_parent_color = (unsigned long)p | color;
+}
+
+static inline void
+__rb_change_child(struct rb_node *old, struct rb_node *new,
+ struct rb_node *parent, struct rb_root *root)
+{
+ if (parent) {
+ if (parent->rb_left == old)
+ parent->rb_left = new;
+ else
+ parent->rb_right = new;
+ } else
+ root->rb_node = new;
+}
+
+extern void __rb_erase_color(struct rb_node *parent, struct rb_root *root,
+ void (*augment_rotate)(struct rb_node *old, struct rb_node *new));
+
+static __always_inline void
+rb_erase_augmented(struct rb_node *node, struct rb_root *root,
+ const struct rb_augment_callbacks *augment)
+{
+ struct rb_node *child = node->rb_right, *tmp = node->rb_left;
+ struct rb_node *parent, *rebalance;
+ unsigned long pc;
+
+ if (!tmp) {
+ /*
+ * Case 1: node to erase has no more than 1 child (easy!)
+ *
+ * Note that if there is one child it must be red due to 5)
+ * and node must be black due to 4). We adjust colors locally
+ * so as to bypass __rb_erase_color() later on.
+ */
+ pc = node->__rb_parent_color;
+ parent = __rb_parent(pc);
+ __rb_change_child(node, child, parent, root);
+ if (child) {
+ child->__rb_parent_color = pc;
+ rebalance = NULL;
+ } else
+ rebalance = __rb_is_black(pc) ? parent : NULL;
+ tmp = parent;
+ } else if (!child) {
+ /* Still case 1, but this time the child is node->rb_left */
+ tmp->__rb_parent_color = pc = node->__rb_parent_color;
+ parent = __rb_parent(pc);
+ __rb_change_child(node, tmp, parent, root);
+ rebalance = NULL;
+ tmp = parent;
+ } else {
+ struct rb_node *successor = child, *child2;
+ tmp = child->rb_left;
+ if (!tmp) {
+ /*
+ * Case 2: node's successor is its right child
+ *
+ * (n) (s)
+ * / \ / \
+ * (x) (s) -> (x) (c)
+ * \
+ * (c)
+ */
+ parent = successor;
+ child2 = successor->rb_right;
+ augment->copy(node, successor);
+ } else {
+ /*
+ * Case 3: node's successor is leftmost under
+ * node's right child subtree
+ *
+ * (n) (s)
+ * / \ / \
+ * (x) (y) -> (x) (y)
+ * / /
+ * (p) (p)
+ * / /
+ * (s) (c)
+ * \
+ * (c)
+ */
+ do {
+ parent = successor;
+ successor = tmp;
+ tmp = tmp->rb_left;
+ } while (tmp);
+ parent->rb_left = child2 = successor->rb_right;
+ successor->rb_right = child;
+ rb_set_parent(child, successor);
+ augment->copy(node, successor);
+ augment->propagate(parent, successor);
+ }
+
+ successor->rb_left = tmp = node->rb_left;
+ rb_set_parent(tmp, successor);
+
+ pc = node->__rb_parent_color;
+ tmp = __rb_parent(pc);
+ __rb_change_child(node, successor, tmp, root);
+ if (child2) {
+ successor->__rb_parent_color = pc;
+ rb_set_parent_color(child2, parent, RB_BLACK);
+ rebalance = NULL;
+ } else {
+ unsigned long pc2 = successor->__rb_parent_color;
+ successor->__rb_parent_color = pc;
+ rebalance = __rb_is_black(pc2) ? parent : NULL;
+ }
+ tmp = successor;
+ }
+
+ augment->propagate(tmp, NULL);
+ if (rebalance)
+ __rb_erase_color(rebalance, root, augment->rotate);
+}
+
+#endif /* _LINUX_RBTREE_AUGMENTED_H */
linux/lib/rbtree.c
*/
-#include <linux/rbtree.h>
+#include <linux/rbtree_augmented.h>
#include <linux/export.h>
/*
* parentheses and have some accompanying text comment.
*/
-#define RB_RED 0
-#define RB_BLACK 1
-
-#define __rb_parent(pc) ((struct rb_node *)(pc & ~3))
-
-#define __rb_color(pc) ((pc) & 1)
-#define __rb_is_black(pc) __rb_color(pc)
-#define __rb_is_red(pc) (!__rb_color(pc))
-#define rb_color(rb) __rb_color((rb)->__rb_parent_color)
-#define rb_is_red(rb) __rb_is_red((rb)->__rb_parent_color)
-#define rb_is_black(rb) __rb_is_black((rb)->__rb_parent_color)
-
static inline void rb_set_black(struct rb_node *rb)
{
rb->__rb_parent_color |= RB_BLACK;
}
-static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
-{
- rb->__rb_parent_color = rb_color(rb) | (unsigned long)p;
-}
-
-static inline void rb_set_parent_color(struct rb_node *rb,
- struct rb_node *p, int color)
-{
- rb->__rb_parent_color = (unsigned long)p | color;
-}
-
static inline struct rb_node *rb_red_parent(struct rb_node *red)
{
return (struct rb_node *)red->__rb_parent_color;
}
-static inline void
-__rb_change_child(struct rb_node *old, struct rb_node *new,
- struct rb_node *parent, struct rb_root *root)
-{
- if (parent) {
- if (parent->rb_left == old)
- parent->rb_left = new;
- else
- parent->rb_right = new;
- } else
- root->rb_node = new;
-}
-
/*
* Helper function for rotations:
* - old's parent and color get assigned to new
}
}
-static __always_inline void
+__always_inline void
__rb_erase_color(struct rb_node *parent, struct rb_root *root,
- const struct rb_augment_callbacks *augment)
+ void (*augment_rotate)(struct rb_node *old, struct rb_node *new))
{
struct rb_node *node = NULL, *sibling, *tmp1, *tmp2;
rb_set_parent_color(tmp1, parent, RB_BLACK);
__rb_rotate_set_parents(parent, sibling, root,
RB_RED);
- augment->rotate(parent, sibling);
+ augment_rotate(parent, sibling);
sibling = tmp1;
}
tmp1 = sibling->rb_right;
if (tmp1)
rb_set_parent_color(tmp1, sibling,
RB_BLACK);
- augment->rotate(sibling, tmp2);
+ augment_rotate(sibling, tmp2);
tmp1 = sibling;
sibling = tmp2;
}
rb_set_parent(tmp2, parent);
__rb_rotate_set_parents(parent, sibling, root,
RB_BLACK);
- augment->rotate(parent, sibling);
+ augment_rotate(parent, sibling);
break;
} else {
sibling = parent->rb_left;
rb_set_parent_color(tmp1, parent, RB_BLACK);
__rb_rotate_set_parents(parent, sibling, root,
RB_RED);
- augment->rotate(parent, sibling);
+ augment_rotate(parent, sibling);
sibling = tmp1;
}
tmp1 = sibling->rb_left;
if (tmp1)
rb_set_parent_color(tmp1, sibling,
RB_BLACK);
- augment->rotate(sibling, tmp2);
+ augment_rotate(sibling, tmp2);
tmp1 = sibling;
sibling = tmp2;
}
rb_set_parent(tmp2, parent);
__rb_rotate_set_parents(parent, sibling, root,
RB_BLACK);
- augment->rotate(parent, sibling);
+ augment_rotate(parent, sibling);
break;
}
}
}
-
-static __always_inline void
-__rb_erase(struct rb_node *node, struct rb_root *root,
- const struct rb_augment_callbacks *augment)
-{
- struct rb_node *child = node->rb_right, *tmp = node->rb_left;
- struct rb_node *parent, *rebalance;
- unsigned long pc;
-
- if (!tmp) {
- /*
- * Case 1: node to erase has no more than 1 child (easy!)
- *
- * Note that if there is one child it must be red due to 5)
- * and node must be black due to 4). We adjust colors locally
- * so as to bypass __rb_erase_color() later on.
- */
- pc = node->__rb_parent_color;
- parent = __rb_parent(pc);
- __rb_change_child(node, child, parent, root);
- if (child) {
- child->__rb_parent_color = pc;
- rebalance = NULL;
- } else
- rebalance = __rb_is_black(pc) ? parent : NULL;
- tmp = parent;
- } else if (!child) {
- /* Still case 1, but this time the child is node->rb_left */
- tmp->__rb_parent_color = pc = node->__rb_parent_color;
- parent = __rb_parent(pc);
- __rb_change_child(node, tmp, parent, root);
- rebalance = NULL;
- tmp = parent;
- } else {
- struct rb_node *successor = child, *child2;
- tmp = child->rb_left;
- if (!tmp) {
- /*
- * Case 2: node's successor is its right child
- *
- * (n) (s)
- * / \ / \
- * (x) (s) -> (x) (c)
- * \
- * (c)
- */
- parent = successor;
- child2 = successor->rb_right;
- augment->copy(node, successor);
- } else {
- /*
- * Case 3: node's successor is leftmost under
- * node's right child subtree
- *
- * (n) (s)
- * / \ / \
- * (x) (y) -> (x) (y)
- * / /
- * (p) (p)
- * / /
- * (s) (c)
- * \
- * (c)
- */
- do {
- parent = successor;
- successor = tmp;
- tmp = tmp->rb_left;
- } while (tmp);
- parent->rb_left = child2 = successor->rb_right;
- successor->rb_right = child;
- rb_set_parent(child, successor);
- augment->copy(node, successor);
- augment->propagate(parent, successor);
- }
-
- successor->rb_left = tmp = node->rb_left;
- rb_set_parent(tmp, successor);
-
- pc = node->__rb_parent_color;
- tmp = __rb_parent(pc);
- __rb_change_child(node, successor, tmp, root);
- if (child2) {
- successor->__rb_parent_color = pc;
- rb_set_parent_color(child2, parent, RB_BLACK);
- rebalance = NULL;
- } else {
- unsigned long pc2 = successor->__rb_parent_color;
- successor->__rb_parent_color = pc;
- rebalance = __rb_is_black(pc2) ? parent : NULL;
- }
- tmp = successor;
- }
-
- augment->propagate(tmp, NULL);
- if (rebalance)
- __rb_erase_color(rebalance, root, augment);
-}
+EXPORT_SYMBOL(__rb_erase_color);
/*
* Non-augmented rbtree manipulation functions.
void rb_erase(struct rb_node *node, struct rb_root *root)
{
- __rb_erase(node, root, &dummy_callbacks);
+ rb_erase_augmented(node, root, &dummy_callbacks);
}
EXPORT_SYMBOL(rb_erase);
}
EXPORT_SYMBOL(__rb_insert_augmented);
-void rb_erase_augmented(struct rb_node *node, struct rb_root *root,
- const struct rb_augment_callbacks *augment)
-{
- __rb_erase(node, root, augment);
-}
-EXPORT_SYMBOL(rb_erase_augmented);
-
/*
* This function returns the first node (in sort order) of the tree.
*/
#include <linux/module.h>
-#include <linux/rbtree.h>
+#include <linux/rbtree_augmented.h>
#include <linux/random.h>
#include <asm/timex.h>
projects / karo-tx-linux.git / commitdiff