perf callchain: Use cached rbtrees

At the cost of an extra pointer, we can avoid the O(logN) cost of
finding the first element in the tree (smallest node), which is
something required for nearly every in/srcline callchain node deletion
(in/srcline__tree_delete()).

Signed-off-by: Davidlohr Bueso <[e-mail]>
Tested-by: Arnaldo Carvalho de Melo <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/dso.c

···
 		dso__set_short_name(dso, dso->name, false);
 		dso->symbols = dso->symbol_names = RB_ROOT;
 		dso->data.cache = RB_ROOT;
-		dso->inlined_nodes = RB_ROOT;
-		dso->srclines = RB_ROOT;
+		dso->inlined_nodes = RB_ROOT_CACHED;
+		dso->srclines = RB_ROOT_CACHED;
 		dso->data.fd = -1;
 		dso->data.status = DSO_DATA_STATUS_UNKNOWN;
 		dso->symtab_type = DSO_BINARY_TYPE__NOT_FOUND;

tools/perf/util/dso.h

···
 	struct rb_root	 *root;		/* root of rbtree that rb_node is in */
 	struct rb_root	 symbols;
 	struct rb_root	 symbol_names;
-	struct rb_root	 inlined_nodes;
-	struct rb_root	 srclines;
+	struct rb_root_cached inlined_nodes;
+	struct rb_root_cached srclines;
 	struct {
 		u64		addr;
 		struct symbol	*symbol;

tools/perf/util/srcline.c

···
 	struct rb_node		rb_node;
 };
 
-void srcline__tree_insert(struct rb_root *tree, u64 addr, char *srcline)
+void srcline__tree_insert(struct rb_root_cached *tree, u64 addr, char *srcline)
 {
-	struct rb_node **p = &tree->rb_node;
+	struct rb_node **p = &tree->rb_root.rb_node;
 	struct rb_node *parent = NULL;
 	struct srcline_node *i, *node;
+	bool leftmost = true;
 
 	node = zalloc(sizeof(struct srcline_node));
 	if (!node) {
···
 		i = rb_entry(parent, struct srcline_node, rb_node);
 		if (addr < i->addr)
 			p = &(*p)->rb_left;
-		else
+		else {
 			p = &(*p)->rb_right;
+			leftmost = false;
+		}
 	}
 	rb_link_node(&node->rb_node, parent, p);
-	rb_insert_color(&node->rb_node, tree);
+	rb_insert_color_cached(&node->rb_node, tree, leftmost);
 }
 
-char *srcline__tree_find(struct rb_root *tree, u64 addr)
+char *srcline__tree_find(struct rb_root_cached *tree, u64 addr)
 {
-	struct rb_node *n = tree->rb_node;
+	struct rb_node *n = tree->rb_root.rb_node;
 
 	while (n) {
 		struct srcline_node *i = rb_entry(n, struct srcline_node,
···
 	return NULL;
 }
 
-void srcline__tree_delete(struct rb_root *tree)
+void srcline__tree_delete(struct rb_root_cached *tree)
 {
 	struct srcline_node *pos;
-	struct rb_node *next = rb_first(tree);
+	struct rb_node *next = rb_first_cached(tree);
 
 	while (next) {
 		pos = rb_entry(next, struct srcline_node, rb_node);
 		next = rb_next(&pos->rb_node);
-		rb_erase(&pos->rb_node, tree);
+		rb_erase_cached(&pos->rb_node, tree);
 		free_srcline(pos->srcline);
 		zfree(&pos);
 	}
···
 	free(node);
 }
 
-void inlines__tree_insert(struct rb_root *tree, struct inline_node *inlines)
+void inlines__tree_insert(struct rb_root_cached *tree,
+			  struct inline_node *inlines)
 {
-	struct rb_node **p = &tree->rb_node;
+	struct rb_node **p = &tree->rb_root.rb_node;
 	struct rb_node *parent = NULL;
 	const u64 addr = inlines->addr;
 	struct inline_node *i;
+	bool leftmost = true;
 
 	while (*p != NULL) {
 		parent = *p;
 		i = rb_entry(parent, struct inline_node, rb_node);
 		if (addr < i->addr)
 			p = &(*p)->rb_left;
-		else
+		else {
 			p = &(*p)->rb_right;
+			leftmost = false;
+		}
 	}
 	rb_link_node(&inlines->rb_node, parent, p);
-	rb_insert_color(&inlines->rb_node, tree);
+	rb_insert_color_cached(&inlines->rb_node, tree, leftmost);
 }
 
-struct inline_node *inlines__tree_find(struct rb_root *tree, u64 addr)
+struct inline_node *inlines__tree_find(struct rb_root_cached *tree, u64 addr)
 {
-	struct rb_node *n = tree->rb_node;
+	struct rb_node *n = tree->rb_root.rb_node;
 
 	while (n) {
 		struct inline_node *i = rb_entry(n, struct inline_node,
···
 	return NULL;
 }
 
-void inlines__tree_delete(struct rb_root *tree)
+void inlines__tree_delete(struct rb_root_cached *tree)
 {
 	struct inline_node *pos;
-	struct rb_node *next = rb_first(tree);
+	struct rb_node *next = rb_first_cached(tree);
 
 	while (next) {
 		pos = rb_entry(next, struct inline_node, rb_node);
 		next = rb_next(&pos->rb_node);
-		rb_erase(&pos->rb_node, tree);
+		rb_erase_cached(&pos->rb_node, tree);
 		inline_node__delete(pos);
 	}
 }

tools/perf/util/srcline.h

···
 char *get_srcline_split(struct dso *dso, u64 addr, unsigned *line);
 
 /* insert the srcline into the DSO, which will take ownership */
-void srcline__tree_insert(struct rb_root *tree, u64 addr, char *srcline);
+void srcline__tree_insert(struct rb_root_cached *tree, u64 addr, char *srcline);
 /* find previously inserted srcline */
-char *srcline__tree_find(struct rb_root *tree, u64 addr);
+char *srcline__tree_find(struct rb_root_cached *tree, u64 addr);
 /* delete all srclines within the tree */
-void srcline__tree_delete(struct rb_root *tree);
+void srcline__tree_delete(struct rb_root_cached *tree);
 
 #define SRCLINE_UNKNOWN  ((char *) "??:0")
 
···
 void inline_node__delete(struct inline_node *node);
 
 /* insert the inline node list into the DSO, which will take ownership */
-void inlines__tree_insert(struct rb_root *tree, struct inline_node *inlines);
+void inlines__tree_insert(struct rb_root_cached *tree,
+			  struct inline_node *inlines);
 /* find previously inserted inline node list */
-struct inline_node *inlines__tree_find(struct rb_root *tree, u64 addr);
+struct inline_node *inlines__tree_find(struct rb_root_cached *tree, u64 addr);
 /* delete all nodes within the tree of inline_node s */
-void inlines__tree_delete(struct rb_root *tree);
+void inlines__tree_delete(struct rb_root_cached *tree);
 
 #endif /* PERF_SRCLINE_H */