^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) /* SPDX-License-Identifier: GPL-2.0-or-later */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) Red Black Trees
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) (C) 1999 Andrea Arcangeli <andrea@suse.de>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) linux/include/linux/rbtree.h
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) To use rbtrees you'll have to implement your own insert and search cores.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) This will avoid us to use callbacks and to drop drammatically performances.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) I know it's not the cleaner way, but in C (not in C++) to get
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) performances and genericity...
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) See Documentation/core-api/rbtree.rst for documentation and samples.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #ifndef __TOOLS_LINUX_PERF_RBTREE_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #define __TOOLS_LINUX_PERF_RBTREE_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <linux/stddef.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) struct rb_node {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) unsigned long __rb_parent_color;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) struct rb_node *rb_right;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) struct rb_node *rb_left;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) } __attribute__((aligned(sizeof(long))));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) /* The alignment might seem pointless, but allegedly CRIS needs it */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) struct rb_root {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) struct rb_node *rb_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) #define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) #define RB_ROOT (struct rb_root) { NULL, }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) #define rb_entry(ptr, type, member) container_of(ptr, type, member)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) #define RB_EMPTY_ROOT(root) (READ_ONCE((root)->rb_node) == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) /* 'empty' nodes are nodes that are known not to be inserted in an rbtree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) #define RB_EMPTY_NODE(node) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) ((node)->__rb_parent_color == (unsigned long)(node))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) #define RB_CLEAR_NODE(node) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) ((node)->__rb_parent_color = (unsigned long)(node))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) extern void rb_insert_color(struct rb_node *, struct rb_root *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) extern void rb_erase(struct rb_node *, struct rb_root *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) /* Find logical next and previous nodes in a tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) extern struct rb_node *rb_next(const struct rb_node *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) extern struct rb_node *rb_prev(const struct rb_node *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) extern struct rb_node *rb_first(const struct rb_root *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) extern struct rb_node *rb_last(const struct rb_root *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) /* Postorder iteration - always visit the parent after its children */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) extern struct rb_node *rb_first_postorder(const struct rb_root *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) extern struct rb_node *rb_next_postorder(const struct rb_node *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) /* Fast replacement of a single node without remove/rebalance/add/rebalance */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) struct rb_root *root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) static inline void rb_link_node(struct rb_node *node, struct rb_node *parent,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) struct rb_node **rb_link)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) node->__rb_parent_color = (unsigned long)parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) node->rb_left = node->rb_right = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) *rb_link = node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) #define rb_entry_safe(ptr, type, member) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) ({ typeof(ptr) ____ptr = (ptr); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) ____ptr ? rb_entry(____ptr, type, member) : NULL; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) })
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) * rbtree_postorder_for_each_entry_safe - iterate in post-order over rb_root of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) * given type allowing the backing memory of @pos to be invalidated
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) * @pos: the 'type *' to use as a loop cursor.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) * @n: another 'type *' to use as temporary storage
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) * @root: 'rb_root *' of the rbtree.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) * @field: the name of the rb_node field within 'type'.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) * rbtree_postorder_for_each_entry_safe() provides a similar guarantee as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) * list_for_each_entry_safe() and allows the iteration to continue independent
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) * of changes to @pos by the body of the loop.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) * Note, however, that it cannot handle other modifications that re-order the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) * rbtree it is iterating over. This includes calling rb_erase() on @pos, as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) * rb_erase() may rebalance the tree, causing us to miss some nodes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) #define rbtree_postorder_for_each_entry_safe(pos, n, root, field) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) for (pos = rb_entry_safe(rb_first_postorder(root), typeof(*pos), field); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) pos && ({ n = rb_entry_safe(rb_next_postorder(&pos->field), \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) typeof(*pos), field); 1; }); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) pos = n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) static inline void rb_erase_init(struct rb_node *n, struct rb_root *root)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) rb_erase(n, root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) RB_CLEAR_NODE(n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) * Leftmost-cached rbtrees.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) * We do not cache the rightmost node based on footprint
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) * size vs number of potential users that could benefit
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) * from O(1) rb_last(). Just not worth it, users that want
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) * this feature can always implement the logic explicitly.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) * Furthermore, users that want to cache both pointers may
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) * find it a bit asymmetric, but that's ok.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) struct rb_root_cached {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) struct rb_root rb_root;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) struct rb_node *rb_leftmost;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) #define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) /* Same as rb_first(), but O(1) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) #define rb_first_cached(root) (root)->rb_leftmost
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) static inline void rb_insert_color_cached(struct rb_node *node,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) struct rb_root_cached *root,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) bool leftmost)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) if (leftmost)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) root->rb_leftmost = node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) rb_insert_color(node, &root->rb_root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) static inline void rb_erase_cached(struct rb_node *node,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) struct rb_root_cached *root)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) if (root->rb_leftmost == node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) root->rb_leftmost = rb_next(node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) rb_erase(node, &root->rb_root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) static inline void rb_replace_node_cached(struct rb_node *victim,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) struct rb_node *new,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) struct rb_root_cached *root)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) if (root->rb_leftmost == victim)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) root->rb_leftmost = new;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) rb_replace_node(victim, new, &root->rb_root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) #endif /* __TOOLS_LINUX_PERF_RBTREE_H */
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Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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