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.
18 #include "callchain.h"
20 #define chain_for_each_child(child, parent) \
21 list_for_each_entry(child, &parent->children, brothers)
24 rb_insert_callchain(struct rb_root *root, struct callchain_node *chain,
27 struct rb_node **p = &root->rb_node;
28 struct rb_node *parent = NULL;
29 struct callchain_node *rnode;
30 u64 chain_cumul = cumul_hits(chain);
36 rnode = rb_entry(parent, struct callchain_node, rb_node);
37 rnode_cumul = cumul_hits(rnode);
41 if (rnode->hit < chain->hit)
46 case CHAIN_GRAPH_ABS: /* Falldown */
48 if (rnode_cumul < chain_cumul)
59 rb_link_node(&chain->rb_node, parent, p);
60 rb_insert_color(&chain->rb_node, root);
64 __sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node,
67 struct callchain_node *child;
69 chain_for_each_child(child, node)
70 __sort_chain_flat(rb_root, child, min_hit);
72 if (node->hit && node->hit >= min_hit)
73 rb_insert_callchain(rb_root, node, CHAIN_FLAT);
77 * Once we get every callchains from the stream, we can now
81 sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node,
82 u64 min_hit, struct callchain_param *param __used)
84 __sort_chain_flat(rb_root, node, min_hit);
87 static void __sort_chain_graph_abs(struct callchain_node *node,
90 struct callchain_node *child;
92 node->rb_root = RB_ROOT;
94 chain_for_each_child(child, node) {
95 __sort_chain_graph_abs(child, min_hit);
96 if (cumul_hits(child) >= min_hit)
97 rb_insert_callchain(&node->rb_root, child,
103 sort_chain_graph_abs(struct rb_root *rb_root, struct callchain_node *chain_root,
104 u64 min_hit, struct callchain_param *param __used)
106 __sort_chain_graph_abs(chain_root, min_hit);
107 rb_root->rb_node = chain_root->rb_root.rb_node;
110 static void __sort_chain_graph_rel(struct callchain_node *node,
113 struct callchain_node *child;
116 node->rb_root = RB_ROOT;
117 min_hit = ceil(node->children_hit * min_percent);
119 chain_for_each_child(child, node) {
120 __sort_chain_graph_rel(child, min_percent);
121 if (cumul_hits(child) >= min_hit)
122 rb_insert_callchain(&node->rb_root, child,
128 sort_chain_graph_rel(struct rb_root *rb_root, struct callchain_node *chain_root,
129 u64 min_hit __used, struct callchain_param *param)
131 __sort_chain_graph_rel(chain_root, param->min_percent / 100.0);
132 rb_root->rb_node = chain_root->rb_root.rb_node;
135 int register_callchain_param(struct callchain_param *param)
137 switch (param->mode) {
138 case CHAIN_GRAPH_ABS:
139 param->sort = sort_chain_graph_abs;
141 case CHAIN_GRAPH_REL:
142 param->sort = sort_chain_graph_rel;
145 param->sort = sort_chain_flat;
155 * Create a child for a parent. If inherit_children, then the new child
156 * will become the new parent of it's parent children
158 static struct callchain_node *
159 create_child(struct callchain_node *parent, bool inherit_children)
161 struct callchain_node *new;
163 new = malloc(sizeof(*new));
165 perror("not enough memory to create child for code path tree");
168 new->parent = parent;
169 INIT_LIST_HEAD(&new->children);
170 INIT_LIST_HEAD(&new->val);
172 if (inherit_children) {
173 struct callchain_node *next;
175 list_splice(&parent->children, &new->children);
176 INIT_LIST_HEAD(&parent->children);
178 chain_for_each_child(next, new)
181 list_add_tail(&new->brothers, &parent->children);
187 * Fill the node with callchain values
190 fill_node(struct callchain_node *node, struct ip_callchain *chain,
191 int start, struct symbol **syms)
195 for (i = start; i < chain->nr; i++) {
196 struct callchain_list *call;
198 call = malloc(sizeof(*call));
200 perror("not enough memory for the code path tree");
203 call->ip = chain->ips[i];
205 list_add_tail(&call->list, &node->val);
207 node->val_nr = chain->nr - start;
209 printf("Warning: empty node in callchain tree\n");
213 add_child(struct callchain_node *parent, struct ip_callchain *chain,
214 int start, struct symbol **syms)
216 struct callchain_node *new;
218 new = create_child(parent, false);
219 fill_node(new, chain, start, syms);
221 new->children_hit = 0;
226 * Split the parent in two parts (a new child is created) and
227 * give a part of its callchain to the created child.
228 * Then create another child to host the given callchain of new branch
231 split_add_child(struct callchain_node *parent, struct ip_callchain *chain,
232 struct callchain_list *to_split, int idx_parents, int idx_local,
233 struct symbol **syms)
235 struct callchain_node *new;
236 struct list_head *old_tail;
237 unsigned int idx_total = idx_parents + idx_local;
240 new = create_child(parent, true);
242 /* split the callchain and move a part to the new child */
243 old_tail = parent->val.prev;
244 list_del_range(&to_split->list, old_tail);
245 new->val.next = &to_split->list;
246 new->val.prev = old_tail;
247 to_split->list.prev = &new->val;
248 old_tail->next = &new->val;
251 new->hit = parent->hit;
252 new->children_hit = parent->children_hit;
253 parent->children_hit = cumul_hits(new);
254 new->val_nr = parent->val_nr - idx_local;
255 parent->val_nr = idx_local;
257 /* create a new child for the new branch if any */
258 if (idx_total < chain->nr) {
260 add_child(parent, chain, idx_total, syms);
261 parent->children_hit++;
268 __append_chain(struct callchain_node *root, struct ip_callchain *chain,
269 unsigned int start, struct symbol **syms);
272 __append_chain_children(struct callchain_node *root, struct ip_callchain *chain,
273 struct symbol **syms, unsigned int start)
275 struct callchain_node *rnode;
277 /* lookup in childrens */
278 chain_for_each_child(rnode, root) {
279 unsigned int ret = __append_chain(rnode, chain, start, syms);
282 goto inc_children_hit;
284 /* nothing in children, add to the current node */
285 add_child(root, chain, start, syms);
288 root->children_hit++;
292 __append_chain(struct callchain_node *root, struct ip_callchain *chain,
293 unsigned int start, struct symbol **syms)
295 struct callchain_list *cnode;
296 unsigned int i = start;
300 * Lookup in the current node
301 * If we have a symbol, then compare the start to match
302 * anywhere inside a function.
304 list_for_each_entry(cnode, &root->val, list) {
307 if (cnode->sym && syms[i]) {
308 if (cnode->sym->start != syms[i]->start)
310 } else if (cnode->ip != chain->ips[i])
317 /* matches not, relay on the parent */
321 /* we match only a part of the node. Split it and add the new chain */
322 if (i - start < root->val_nr) {
323 split_add_child(root, chain, cnode, start, i - start, syms);
327 /* we match 100% of the path, increment the hit */
328 if (i - start == root->val_nr && i == chain->nr) {
333 /* We match the node and still have a part remaining */
334 __append_chain_children(root, chain, syms, i);
339 void append_chain(struct callchain_node *root, struct ip_callchain *chain,
340 struct symbol **syms)
344 __append_chain_children(root, chain, syms, 0);