diff options
| -rw-r--r-- | Documentation/rbtree.txt | 13 | ||||
| -rw-r--r-- | arch/x86/mm/pat_rbtree.c | 2 | ||||
| -rw-r--r-- | include/linux/interval_tree_tmpl.h | 8 | ||||
| -rw-r--r-- | include/linux/rbtree.h | 48 | ||||
| -rw-r--r-- | include/linux/rbtree_augmented.h | 223 | ||||
| -rw-r--r-- | lib/rbtree.c | 162 | ||||
| -rw-r--r-- | lib/rbtree_test.c | 2 |
7 files changed, 255 insertions, 203 deletions
diff --git a/Documentation/rbtree.txt b/Documentation/rbtree.txt index 0a0b6dce3e0..61b6c48871a 100644 --- a/Documentation/rbtree.txt +++ b/Documentation/rbtree.txt @@ -202,6 +202,14 @@ An rbtree user who wants this feature will have to call the augmentation 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. @@ -227,6 +235,11 @@ In both cases, the callbacks are provided through struct rb_augment_callbacks. 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: diff --git a/arch/x86/mm/pat_rbtree.c b/arch/x86/mm/pat_rbtree.c index 4d116959075..415f6c4ced3 100644 --- a/arch/x86/mm/pat_rbtree.c +++ b/arch/x86/mm/pat_rbtree.c @@ -12,7 +12,7 @@ #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> diff --git a/include/linux/interval_tree_tmpl.h b/include/linux/interval_tree_tmpl.h index c65deda3141..c1aeb922d65 100644 --- a/include/linux/interval_tree_tmpl.h +++ b/include/linux/interval_tree_tmpl.h @@ -19,6 +19,8 @@ include/linux/interval_tree_tmpl.h */ +#include <linux/rbtree_augmented.h> + /* * Template for implementing interval trees * @@ -57,7 +59,8 @@ static inline ITTYPE IT(compute_subtree_last)(ITSTRUCT *node) 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); @@ -69,7 +72,8 @@ static void IT(augment_propagate)(struct rb_node *rb, struct rb_node *stop) } } -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); diff --git a/include/linux/rbtree.h b/include/linux/rbtree.h index 8d1e83b1c87..0022c1bb1e2 100644 --- a/include/linux/rbtree.h +++ b/include/linux/rbtree.h @@ -62,54 +62,6 @@ extern void rb_insert_color(struct rb_node *, struct rb_root *); 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 *); diff --git a/include/linux/rbtree_augmented.h b/include/linux/rbtree_augmented.h new file mode 100644 index 00000000000..214caa33433 --- /dev/null +++ b/include/linux/rbtree_augmented.h @@ -0,0 +1,223 @@ +/* + 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 */ diff --git a/lib/rbtree.c b/lib/rbtree.c index c0088ca345f..4f56a11d67f 100644 --- a/lib/rbtree.c +++ b/lib/rbtree.c @@ -21,7 +21,7 @@ linux/lib/rbtree.c */ -#include <linux/rbtree.h> +#include <linux/rbtree_augmented.h> #include <linux/export.h> /* @@ -44,52 +44,16 @@ * 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 @@ -230,9 +194,9 @@ __rb_insert(struct rb_node *node, struct rb_root *root, } } -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; @@ -261,7 +225,7 @@ __rb_erase_color(struct rb_node *parent, struct rb_root *root, 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; @@ -313,7 +277,7 @@ __rb_erase_color(struct rb_node *parent, struct rb_root *root, if (tmp1) rb_set_parent_color(tmp1, sibling, RB_BLACK); - augment->rotate(sibling, tmp2); + augment_rotate(sibling, tmp2); tmp1 = sibling; sibling = tmp2; } @@ -336,7 +300,7 @@ __rb_erase_color(struct rb_node *parent, struct rb_root *root, 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; @@ -347,7 +311,7 @@ __rb_erase_color(struct rb_node *parent, struct rb_root *root, 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; @@ -374,7 +338,7 @@ __rb_erase_color(struct rb_node *parent, struct rb_root *root, if (tmp1) rb_set_parent_color(tmp1, sibling, RB_BLACK); - augment->rotate(sibling, tmp2); + augment_rotate(sibling, tmp2); tmp1 = sibling; sibling = tmp2; } @@ -386,109 +350,12 @@ __rb_erase_color(struct rb_node *parent, struct rb_root *root, 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. @@ -513,7 +380,7 @@ EXPORT_SYMBOL(rb_insert_color); 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); @@ -531,13 +398,6 @@ void __rb_insert_augmented(struct rb_node *node, struct rb_root *root, } 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. */ diff --git a/lib/rbtree_test.c b/lib/rbtree_test.c index b20e99969b0..268b23951fe 100644 --- a/lib/rbtree_test.c +++ b/lib/rbtree_test.c @@ -1,5 +1,5 @@ #include <linux/module.h> -#include <linux/rbtree.h> +#include <linux/rbtree_augmented.h> #include <linux/random.h> #include <asm/timex.h> |