1 files changed, 216 insertions, 47 deletions

diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index ad3c28578961..011473411642 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -4,52 +4,157 @@
  * Handle the callchains from the stream in an ad-hoc radix tree and then
  * sort them in an rbtree.
  *
+ * Using a radix for code path provides a fast retrieval and factorizes
+ * memory use. Also that lets us use the paths in a hierarchical graph view.
+ *
  */
 
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdbool.h>
 #include <errno.h>
+#include <math.h>
 
 #include "callchain.h"
 
+#define chain_for_each_child(child, parent)     \
+        list_for_each_entry(child, &parent->children, brothers)
 
-static void rb_insert_callchain(struct rb_root *root, struct callchain_node *chain)
+static void
+rb_insert_callchain(struct rb_root *root, struct callchain_node *chain,
+                    enum chain_mode mode)
 {
         struct rb_node **p = &root->rb_node;
         struct rb_node *parent = NULL;
         struct callchain_node *rnode;
+        u64 chain_cumul = cumul_hits(chain);
 
         while (*p) {
+                u64 rnode_cumul;
+
                 parent = *p;
                 rnode = rb_entry(parent, struct callchain_node, rb_node);
-
-                if (rnode->hit < chain->hit)
-                        p = &(*p)->rb_left;
-                else
-                        p = &(*p)->rb_right;
+                rnode_cumul = cumul_hits(rnode);
+
+                switch (mode) {
+                case CHAIN_FLAT:
+                        if (rnode->hit < chain->hit)
+                                p = &(*p)->rb_left;
+                        else
+                                p = &(*p)->rb_right;
+                        break;
+                case CHAIN_GRAPH_ABS: /* Falldown */
+                case CHAIN_GRAPH_REL:
+                        if (rnode_cumul < chain_cumul)
+                                p = &(*p)->rb_left;
+                        else
+                                p = &(*p)->rb_right;
+                        break;
+                default:
+                        break;
+                }
         }
 
         rb_link_node(&chain->rb_node, parent, p);
         rb_insert_color(&chain->rb_node, root);
 }
 
+static void
+__sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node,
+                  u64 min_hit)
+{
+        struct callchain_node *child;
+
+        chain_for_each_child(child, node)
+                __sort_chain_flat(rb_root, child, min_hit);
+
+        if (node->hit && node->hit >= min_hit)
+                rb_insert_callchain(rb_root, node, CHAIN_FLAT);
+}
+
 /*
  * Once we get every callchains from the stream, we can now
  * sort them by hit
  */
-void sort_chain_to_rbtree(struct rb_root *rb_root, struct callchain_node *node)
+static void
+sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node,
+                u64 min_hit, struct callchain_param *param __used)
+{
+        __sort_chain_flat(rb_root, node, min_hit);
+}
+
+static void __sort_chain_graph_abs(struct callchain_node *node,
+                                   u64 min_hit)
+{
+        struct callchain_node *child;
+
+        node->rb_root = RB_ROOT;
+
+        chain_for_each_child(child, node) {
+                __sort_chain_graph_abs(child, min_hit);
+                if (cumul_hits(child) >= min_hit)
+                        rb_insert_callchain(&node->rb_root, child,
+                                            CHAIN_GRAPH_ABS);
+        }
+}
+
+static void
+sort_chain_graph_abs(struct rb_root *rb_root, struct callchain_node *chain_root,
+                     u64 min_hit, struct callchain_param *param __used)
+{
+        __sort_chain_graph_abs(chain_root, min_hit);
+        rb_root->rb_node = chain_root->rb_root.rb_node;
+}
+
+static void __sort_chain_graph_rel(struct callchain_node *node,
+                                   double min_percent)
 {
         struct callchain_node *child;
+        u64 min_hit;
+
+        node->rb_root = RB_ROOT;
+        min_hit = ceil(node->children_hit * min_percent);
+
+        chain_for_each_child(child, node) {
+                __sort_chain_graph_rel(child, min_percent);
+                if (cumul_hits(child) >= min_hit)
+                        rb_insert_callchain(&node->rb_root, child,
+                                            CHAIN_GRAPH_REL);
+        }
+}
 
-        list_for_each_entry(child, &node->children, brothers)
-                sort_chain_to_rbtree(rb_root, child);
+static void
+sort_chain_graph_rel(struct rb_root *rb_root, struct callchain_node *chain_root,
+                     u64 min_hit __used, struct callchain_param *param)
+{
+        __sort_chain_graph_rel(chain_root, param->min_percent / 100.0);
+        rb_root->rb_node = chain_root->rb_root.rb_node;
+}
 
-        if (node->hit)
-                rb_insert_callchain(rb_root, node);
+int register_callchain_param(struct callchain_param *param)
+{
+        switch (param->mode) {
+        case CHAIN_GRAPH_ABS:
+                param->sort = sort_chain_graph_abs;
+                break;
+        case CHAIN_GRAPH_REL:
+                param->sort = sort_chain_graph_rel;
+                break;
+        case CHAIN_FLAT:
+                param->sort = sort_chain_flat;
+                break;
+        default:
+                return -1;
+        }
+        return 0;
 }
 
-static struct callchain_node *create_child(struct callchain_node *parent)
+/*
+ * Create a child for a parent. If inherit_children, then the new child
+ * will become the new parent of it's parent children
+ */
+static struct callchain_node *
+create_child(struct callchain_node *parent, bool inherit_children)
 {
         struct callchain_node *new;
 
@@ -61,91 +166,150 @@ static struct callchain_node *create_child(struct callchain_node *parent)
         new->parent = parent;
         INIT_LIST_HEAD(&new->children);
         INIT_LIST_HEAD(&new->val);
+
+        if (inherit_children) {
+                struct callchain_node *next;
+
+                list_splice(&parent->children, &new->children);
+                INIT_LIST_HEAD(&parent->children);
+
+                chain_for_each_child(next, new)
+                        next->parent = new;
+        }
         list_add_tail(&new->brothers, &parent->children);
 
         return new;
 }
 
+/*
+ * Fill the node with callchain values
+ */
 static void
-fill_node(struct callchain_node *node, struct ip_callchain *chain, int start)
+fill_node(struct callchain_node *node, struct ip_callchain *chain,
+          int start, struct symbol **syms)
 {
-        int i;
+        unsigned int i;
 
         for (i = start; i < chain->nr; i++) {
                 struct callchain_list *call;
 
-                call = malloc(sizeof(*chain));
+                call = malloc(sizeof(*call));
                 if (!call) {
                         perror("not enough memory for the code path tree");
                         return;
                 }
                 call->ip = chain->ips[i];
+                call->sym = syms[i];
                 list_add_tail(&call->list, &node->val);
         }
-        node->val_nr = i - start;
+        node->val_nr = chain->nr - start;
+        if (!node->val_nr)
+                printf("Warning: empty node in callchain tree\n");
 }
 
-static void add_child(struct callchain_node *parent, struct ip_callchain *chain)
+static void
+add_child(struct callchain_node *parent, struct ip_callchain *chain,
+          int start, struct symbol **syms)
 {
         struct callchain_node *new;
 
-        new = create_child(parent);
-        fill_node(new, chain, parent->val_nr);
+        new = create_child(parent, false);
+        fill_node(new, chain, start, syms);
 
+        new->children_hit = 0;
         new->hit = 1;
 }
 
+/*
+ * Split the parent in two parts (a new child is created) and
+ * give a part of its callchain to the created child.
+ * Then create another child to host the given callchain of new branch
+ */
 static void
 split_add_child(struct callchain_node *parent, struct ip_callchain *chain,
-                struct callchain_list *to_split, int idx)
+                struct callchain_list *to_split, int idx_parents, int idx_local,
+                struct symbol **syms)
 {
         struct callchain_node *new;
+        struct list_head *old_tail;
+        unsigned int idx_total = idx_parents + idx_local;
 
         /* split */
-        new = create_child(parent);
-        list_move_tail(&to_split->list, &new->val);
-        new->hit = parent->hit;
-        parent->hit = 0;
-        parent->val_nr = idx;
+        new = create_child(parent, true);
 
-        /* create the new one */
-        add_child(parent, chain);
+        /* split the callchain and move a part to the new child */
+        old_tail = parent->val.prev;
+        list_del_range(&to_split->list, old_tail);
+        new->val.next = &to_split->list;
+        new->val.prev = old_tail;
+        to_split->list.prev = &new->val;
+        old_tail->next = &new->val;
+
+        /* split the hits */
+        new->hit = parent->hit;
+        new->children_hit = parent->children_hit;
+        parent->children_hit = cumul_hits(new);
+        new->val_nr = parent->val_nr - idx_local;
+        parent->val_nr = idx_local;
+
+        /* create a new child for the new branch if any */
+        if (idx_total < chain->nr) {
+                parent->hit = 0;
+                add_child(parent, chain, idx_total, syms);
+                parent->children_hit++;
+        } else {
+                parent->hit = 1;
+        }
 }
 
 static int
 __append_chain(struct callchain_node *root, struct ip_callchain *chain,
-                int start);
+               unsigned int start, struct symbol **syms);
 
-static int
-__append_chain_children(struct callchain_node *root, struct ip_callchain *chain)
+static void
+__append_chain_children(struct callchain_node *root, struct ip_callchain *chain,
+                        struct symbol **syms, unsigned int start)
 {
         struct callchain_node *rnode;
 
         /* lookup in childrens */
-        list_for_each_entry(rnode, &root->children, brothers) {
-                int ret = __append_chain(rnode, chain, root->val_nr);
+        chain_for_each_child(rnode, root) {
+                unsigned int ret = __append_chain(rnode, chain, start, syms);
+
                 if (!ret)
-                        return 0;
+                        goto inc_children_hit;
         }
-        return -1;
+        /* nothing in children, add to the current node */
+        add_child(root, chain, start, syms);
+
+inc_children_hit:
+        root->children_hit++;
 }
 
 static int
 __append_chain(struct callchain_node *root, struct ip_callchain *chain,
-                int start)
+               unsigned int start, struct symbol **syms)
 {
         struct callchain_list *cnode;
-        int i = start;
+        unsigned int i = start;
         bool found = false;
 
-        /* lookup in the current node */
+        /*
+         * Lookup in the current node
+         * If we have a symbol, then compare the start to match
+         * anywhere inside a function.
+         */
         list_for_each_entry(cnode, &root->val, list) {
-                if (cnode->ip != chain->ips[i++])
+                if (i == chain->nr)
+                        break;
+                if (cnode->sym && syms[i]) {
+                        if (cnode->sym->start != syms[i]->start)
+                                break;
+                } else if (cnode->ip != chain->ips[i])
                         break;
                 if (!found)
                         found = true;
-                if (i == chain->nr)
-                        break;
+                i++;
         }
 
         /* matches not, relay on the parent */
@@ -153,22 +317,27 @@ __append_chain(struct callchain_node *root, struct ip_callchain *chain,
                 return -1;
 
         /* we match only a part of the node. Split it and add the new chain */
-        if (i < root->val_nr) {
-                split_add_child(root, chain, cnode, i);
+        if (i - start < root->val_nr) {
+                split_add_child(root, chain, cnode, start, i - start, syms);
                 return 0;
         }
 
         /* we match 100% of the path, increment the hit */
-        if (i == root->val_nr) {
+        if (i - start == root->val_nr && i == chain->nr) {
                 root->hit++;
                 return 0;
         }
 
-        return __append_chain_children(root, chain);
+        /* We match the node and still have a part remaining */
+        __append_chain_children(root, chain, syms, i);
+
+        return 0;
 }
 
-void append_chain(struct callchain_node *root, struct ip_callchain *chain)
+void append_chain(struct callchain_node *root, struct ip_callchain *chain,
+                  struct symbol **syms)
 {
-        if (__append_chain_children(root, chain) == -1)
-                add_child(root, chain);
+        if (!chain->nr)
+                return;
+        __append_chain_children(root, chain, syms, 0);
 }