From c7d4f7eeb6da9408e9ba7475fe2624bdb4d837d0 Mon Sep 17 00:00:00 2001
From: Michel Lespinasse <walken@google.com>
Date: Wed, 25 Sep 2019 16:46:02 -0700
Subject: [PATCH] rbtree: avoid generating code twice for the cached versions (tools copy)
Git-commit: c7d4f7eeb6da9408e9ba7475fe2624bdb4d837d0
Patch-mainline: v5.4-rc1
References: bsc#1159864
As was already noted in rbtree.h, the logic to cache rb_first (or
rb_last) can easily be implemented externally to the core rbtree api.
This commit takes the changes applied to the include/linux/ and lib/
rbtree files in 9f973cb38088 ("lib/rbtree: avoid generating code twice
for the cached versions"), and applies these to the
tools/include/linux/ and tools/lib/ files as well to keep them
synchronized.
Link: http://lkml.kernel.org/r/20190703034812.53002-1-walken@google.com
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
tools/include/linux/rbtree.h | 71 ++++++++++++++++++++++------------
tools/include/linux/rbtree_augmented.h | 31 ++++++---------
tools/lib/rbtree.c | 37 ++----------------
3 files changed, 62 insertions(+), 77 deletions(-)
diff --git a/tools/include/linux/rbtree.h b/tools/include/linux/rbtree.h
index d83763a5327c..e03b1ea23e0e 100644
--- a/tools/include/linux/rbtree.h
+++ b/tools/include/linux/rbtree.h
@@ -31,25 +31,9 @@ struct rb_root {
struct rb_node *rb_node;
};
-/*
- * Leftmost-cached rbtrees.
- *
- * We do not cache the rightmost node based on footprint
- * size vs number of potential users that could benefit
- * from O(1) rb_last(). Just not worth it, users that want
- * this feature can always implement the logic explicitly.
- * Furthermore, users that want to cache both pointers may
- * find it a bit asymmetric, but that's ok.
- */
-struct rb_root_cached {
- struct rb_root rb_root;
- struct rb_node *rb_leftmost;
-};
-
#define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3))
#define RB_ROOT (struct rb_root) { NULL, }
-#define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL }
#define rb_entry(ptr, type, member) container_of(ptr, type, member)
#define RB_EMPTY_ROOT(root) (READ_ONCE((root)->rb_node) == NULL)
@@ -71,12 +55,6 @@ extern struct rb_node *rb_prev(const struct rb_node *);
extern struct rb_node *rb_first(const struct rb_root *);
extern struct rb_node *rb_last(const struct rb_root *);
-extern void rb_insert_color_cached(struct rb_node *,
- struct rb_root_cached *, bool);
-extern void rb_erase_cached(struct rb_node *node, struct rb_root_cached *);
-/* Same as rb_first(), but O(1) */
-#define rb_first_cached(root) (root)->rb_leftmost
-
/* Postorder iteration - always visit the parent after its children */
extern struct rb_node *rb_first_postorder(const struct rb_root *);
extern struct rb_node *rb_next_postorder(const struct rb_node *);
@@ -84,8 +62,6 @@ extern struct rb_node *rb_next_postorder(const struct rb_node *);
/* Fast replacement of a single node without remove/rebalance/add/rebalance */
extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
struct rb_root *root);
-extern void rb_replace_node_cached(struct rb_node *victim, struct rb_node *new,
- struct rb_root_cached *root);
static inline void rb_link_node(struct rb_node *node, struct rb_node *parent,
struct rb_node **rb_link)
@@ -129,4 +105,51 @@ static inline void rb_erase_init(struct rb_node *n, struct rb_root *root)
rb_erase(n, root);
RB_CLEAR_NODE(n);
}
+
+/*
+ * Leftmost-cached rbtrees.
+ *
+ * We do not cache the rightmost node based on footprint
+ * size vs number of potential users that could benefit
+ * from O(1) rb_last(). Just not worth it, users that want
+ * this feature can always implement the logic explicitly.
+ * Furthermore, users that want to cache both pointers may
+ * find it a bit asymmetric, but that's ok.
+ */
+struct rb_root_cached {
+ struct rb_root rb_root;
+ struct rb_node *rb_leftmost;
+};
+
+#define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL }
+
+/* Same as rb_first(), but O(1) */
+#define rb_first_cached(root) (root)->rb_leftmost
+
+static inline void rb_insert_color_cached(struct rb_node *node,
+ struct rb_root_cached *root,
+ bool leftmost)
+{
+ if (leftmost)
+ root->rb_leftmost = node;
+ rb_insert_color(node, &root->rb_root);
+}
+
+static inline void rb_erase_cached(struct rb_node *node,
+ struct rb_root_cached *root)
+{
+ if (root->rb_leftmost == node)
+ root->rb_leftmost = rb_next(node);
+ rb_erase(node, &root->rb_root);
+}
+
+static inline void rb_replace_node_cached(struct rb_node *victim,
+ struct rb_node *new,
+ struct rb_root_cached *root)
+{
+ if (root->rb_leftmost == victim)
+ root->rb_leftmost = new;
+ rb_replace_node(victim, new, &root->rb_root);
+}
+
#endif /* __TOOLS_LINUX_PERF_RBTREE_H */
diff --git a/tools/include/linux/rbtree_augmented.h b/tools/include/linux/rbtree_augmented.h
index ddd01006ece5..467a3eefe1d2 100644
--- a/tools/include/linux/rbtree_augmented.h
+++ b/tools/include/linux/rbtree_augmented.h
@@ -32,17 +32,16 @@ struct rb_augment_callbacks {
void (*rotate)(struct rb_node *old, struct rb_node *new);
};
-extern void __rb_insert_augmented(struct rb_node *node,
- struct rb_root *root,
- bool newleft, struct rb_node **leftmost,
+extern void __rb_insert_augmented(struct rb_node *node, struct rb_root *root,
void (*augment_rotate)(struct rb_node *old, struct rb_node *new));
+
/*
* Fixup the rbtree and update the augmented information when rebalancing.
*
* 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.
- * If rb_augment_inserted() rebalances the rbtree, it will callback into
+ * rb_insert_augmented() instead of the usual rb_insert_color() call.
+ * If rb_insert_augmented() rebalances the rbtree, it will callback into
* a user provided function to update the augmented information on the
* affected subtrees.
*/
@@ -50,7 +49,7 @@ 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, false, NULL, augment->rotate);
+ __rb_insert_augmented(node, root, augment->rotate);
}
static inline void
@@ -58,8 +57,9 @@ rb_insert_augmented_cached(struct rb_node *node,
struct rb_root_cached *root, bool newleft,
const struct rb_augment_callbacks *augment)
{
- __rb_insert_augmented(node, &root->rb_root,
- newleft, &root->rb_leftmost, augment->rotate);
+ if (newleft)
+ root->rb_leftmost = node;
+ rb_insert_augmented(node, &root->rb_root, augment);
}
#define RB_DECLARE_CALLBACKS(rbstatic, rbname, rbstruct, rbfield, \
@@ -139,7 +139,6 @@ extern void __rb_erase_color(struct rb_node *parent, struct rb_root *root,
static __always_inline struct rb_node *
__rb_erase_augmented(struct rb_node *node, struct rb_root *root,
- struct rb_node **leftmost,
const struct rb_augment_callbacks *augment)
{
struct rb_node *child = node->rb_right;
@@ -147,9 +146,6 @@ __rb_erase_augmented(struct rb_node *node, struct rb_root *root,
struct rb_node *parent, *rebalance;
unsigned long pc;
- if (leftmost && node == *leftmost)
- *leftmost = rb_next(node);
-
if (!tmp) {
/*
* Case 1: node to erase has no more than 1 child (easy!)
@@ -249,8 +245,7 @@ static __always_inline void
rb_erase_augmented(struct rb_node *node, struct rb_root *root,
const struct rb_augment_callbacks *augment)
{
- struct rb_node *rebalance = __rb_erase_augmented(node, root,
- NULL, augment);
+ struct rb_node *rebalance = __rb_erase_augmented(node, root, augment);
if (rebalance)
__rb_erase_color(rebalance, root, augment->rotate);
}
@@ -259,11 +254,9 @@ static __always_inline void
rb_erase_augmented_cached(struct rb_node *node, struct rb_root_cached *root,
const struct rb_augment_callbacks *augment)
{
- struct rb_node *rebalance = __rb_erase_augmented(node, &root->rb_root,
- &root->rb_leftmost,
- augment);
- if (rebalance)
- __rb_erase_color(rebalance, &root->rb_root, augment->rotate);
+ if (root->rb_leftmost == node)
+ root->rb_leftmost = rb_next(node);
+ rb_erase_augmented(node, &root->rb_root, augment);
}
#endif /* _TOOLS_LINUX_RBTREE_AUGMENTED_H */
diff --git a/tools/lib/rbtree.c b/tools/lib/rbtree.c
index 804f145e3113..2548ff8c4d9c 100644
--- a/tools/lib/rbtree.c
+++ b/tools/lib/rbtree.c
@@ -83,14 +83,10 @@ __rb_rotate_set_parents(struct rb_node *old, struct rb_node *new,
static __always_inline void
__rb_insert(struct rb_node *node, struct rb_root *root,
- bool newleft, struct rb_node **leftmost,
void (*augment_rotate)(struct rb_node *old, struct rb_node *new))
{
struct rb_node *parent = rb_red_parent(node), *gparent, *tmp;
- if (newleft)
- *leftmost = node;
-
while (true) {
/*
* Loop invariant: node is red.
@@ -436,34 +432,17 @@ static const struct rb_augment_callbacks dummy_callbacks = {
void rb_insert_color(struct rb_node *node, struct rb_root *root)
{
- __rb_insert(node, root, false, NULL, dummy_rotate);
+ __rb_insert(node, root, dummy_rotate);
}
void rb_erase(struct rb_node *node, struct rb_root *root)
{
struct rb_node *rebalance;
- rebalance = __rb_erase_augmented(node, root,
- NULL, &dummy_callbacks);
+ rebalance = __rb_erase_augmented(node, root, &dummy_callbacks);
if (rebalance)
____rb_erase_color(rebalance, root, dummy_rotate);
}
-void rb_insert_color_cached(struct rb_node *node,
- struct rb_root_cached *root, bool leftmost)
-{
- __rb_insert(node, &root->rb_root, leftmost,
- &root->rb_leftmost, dummy_rotate);
-}
-
-void rb_erase_cached(struct rb_node *node, struct rb_root_cached *root)
-{
- struct rb_node *rebalance;
- rebalance = __rb_erase_augmented(node, &root->rb_root,
- &root->rb_leftmost, &dummy_callbacks);
- if (rebalance)
- ____rb_erase_color(rebalance, &root->rb_root, dummy_rotate);
-}
-
/*
* Augmented rbtree manipulation functions.
*
@@ -472,10 +451,9 @@ void rb_erase_cached(struct rb_node *node, struct rb_root_cached *root)
*/
void __rb_insert_augmented(struct rb_node *node, struct rb_root *root,
- bool newleft, struct rb_node **leftmost,
void (*augment_rotate)(struct rb_node *old, struct rb_node *new))
{
- __rb_insert(node, root, newleft, leftmost, augment_rotate);
+ __rb_insert(node, root, augment_rotate);
}
/*
@@ -580,15 +558,6 @@ void rb_replace_node(struct rb_node *victim, struct rb_node *new,
__rb_change_child(victim, new, parent, root);
}
-void rb_replace_node_cached(struct rb_node *victim, struct rb_node *new,
- struct rb_root_cached *root)
-{
- rb_replace_node(victim, new, &root->rb_root);
-
- if (root->rb_leftmost == victim)
- root->rb_leftmost = new;
-}
-
static struct rb_node *rb_left_deepest_node(const struct rb_node *node)
{
for (;;) {
--
2.16.4