2 * Copyright (C) 2009, Frederic Weisbecker <fweisbec@gmail.com>
4 * Handle the callchains from the stream in an ad-hoc radix tree and then
5 * sort them in an rbtree.
7 * Using a radix for code path provides a fast retrieval and factorizes
8 * memory use. Also that lets us use the paths in a hierarchical graph view.
17 #include "callchain.h"
19 #define chain_for_each_child(child, parent) \
20 list_for_each_entry(child, &parent->children, brothers)
23 rb_insert_callchain(struct rb_root *root, struct callchain_node *chain,
26 struct rb_node **p = &root->rb_node;
27 struct rb_node *parent = NULL;
28 struct callchain_node *rnode;
32 rnode = rb_entry(parent, struct callchain_node, rb_node);
36 if (rnode->hit < chain->hit)
42 if (rnode->cumul_hit < chain->cumul_hit)
52 rb_link_node(&chain->rb_node, parent, p);
53 rb_insert_color(&chain->rb_node, root);
57 * Once we get every callchains from the stream, we can now
60 void sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node,
63 struct callchain_node *child;
65 chain_for_each_child(child, node)
66 sort_chain_flat(rb_root, child, min_hit);
68 if (node->hit && node->hit >= min_hit)
69 rb_insert_callchain(rb_root, node, FLAT);
72 static void __sort_chain_graph(struct callchain_node *node, u64 min_hit)
74 struct callchain_node *child;
76 node->rb_root = RB_ROOT;
77 node->cumul_hit = node->hit;
79 chain_for_each_child(child, node) {
80 __sort_chain_graph(child, min_hit);
81 if (child->cumul_hit >= min_hit)
82 rb_insert_callchain(&node->rb_root, child, GRAPH);
83 node->cumul_hit += child->cumul_hit;
88 sort_chain_graph(struct rb_root *rb_root, struct callchain_node *chain_root,
91 __sort_chain_graph(chain_root, min_hit);
92 rb_root->rb_node = chain_root->rb_root.rb_node;
96 * Create a child for a parent. If inherit_children, then the new child
97 * will become the new parent of it's parent children
99 static struct callchain_node *
100 create_child(struct callchain_node *parent, bool inherit_children)
102 struct callchain_node *new;
104 new = malloc(sizeof(*new));
106 perror("not enough memory to create child for code path tree");
109 new->parent = parent;
110 INIT_LIST_HEAD(&new->children);
111 INIT_LIST_HEAD(&new->val);
113 if (inherit_children) {
114 struct callchain_node *next;
116 list_splice(&parent->children, &new->children);
117 INIT_LIST_HEAD(&parent->children);
119 chain_for_each_child(next, new)
122 list_add_tail(&new->brothers, &parent->children);
128 * Fill the node with callchain values
131 fill_node(struct callchain_node *node, struct ip_callchain *chain,
132 int start, struct symbol **syms)
136 for (i = start; i < chain->nr; i++) {
137 struct callchain_list *call;
139 call = malloc(sizeof(*call));
141 perror("not enough memory for the code path tree");
144 call->ip = chain->ips[i];
146 list_add_tail(&call->list, &node->val);
148 node->val_nr = chain->nr - start;
150 printf("Warning: empty node in callchain tree\n");
154 add_child(struct callchain_node *parent, struct ip_callchain *chain,
155 int start, struct symbol **syms)
157 struct callchain_node *new;
159 new = create_child(parent, false);
160 fill_node(new, chain, start, syms);
166 * Split the parent in two parts (a new child is created) and
167 * give a part of its callchain to the created child.
168 * Then create another child to host the given callchain of new branch
171 split_add_child(struct callchain_node *parent, struct ip_callchain *chain,
172 struct callchain_list *to_split, int idx_parents, int idx_local,
173 struct symbol **syms)
175 struct callchain_node *new;
176 struct list_head *old_tail;
177 unsigned int idx_total = idx_parents + idx_local;
180 new = create_child(parent, true);
182 /* split the callchain and move a part to the new child */
183 old_tail = parent->val.prev;
184 list_del_range(&to_split->list, old_tail);
185 new->val.next = &to_split->list;
186 new->val.prev = old_tail;
187 to_split->list.prev = &new->val;
188 old_tail->next = &new->val;
191 new->hit = parent->hit;
192 new->val_nr = parent->val_nr - idx_local;
193 parent->val_nr = idx_local;
195 /* create a new child for the new branch if any */
196 if (idx_total < chain->nr) {
198 add_child(parent, chain, idx_total, syms);
205 __append_chain(struct callchain_node *root, struct ip_callchain *chain,
206 unsigned int start, struct symbol **syms);
209 __append_chain_children(struct callchain_node *root, struct ip_callchain *chain,
210 struct symbol **syms, unsigned int start)
212 struct callchain_node *rnode;
214 /* lookup in childrens */
215 chain_for_each_child(rnode, root) {
216 unsigned int ret = __append_chain(rnode, chain, start, syms);
221 /* nothing in children, add to the current node */
222 add_child(root, chain, start, syms);
226 __append_chain(struct callchain_node *root, struct ip_callchain *chain,
227 unsigned int start, struct symbol **syms)
229 struct callchain_list *cnode;
230 unsigned int i = start;
234 * Lookup in the current node
235 * If we have a symbol, then compare the start to match
236 * anywhere inside a function.
238 list_for_each_entry(cnode, &root->val, list) {
241 if (cnode->sym && syms[i]) {
242 if (cnode->sym->start != syms[i]->start)
244 } else if (cnode->ip != chain->ips[i])
251 /* matches not, relay on the parent */
255 /* we match only a part of the node. Split it and add the new chain */
256 if (i - start < root->val_nr) {
257 split_add_child(root, chain, cnode, start, i - start, syms);
261 /* we match 100% of the path, increment the hit */
262 if (i - start == root->val_nr && i == chain->nr) {
267 /* We match the node and still have a part remaining */
268 __append_chain_children(root, chain, syms, i);
273 void append_chain(struct callchain_node *root, struct ip_callchain *chain,
274 struct symbol **syms)
276 __append_chain_children(root, chain, syms, 0);