LXR linux/tools/perf/util/call-path.c

   1/*
   2 * call-path.h: Manipulate a tree data structure containing function call paths
   3 * Copyright (c) 2014, Intel Corporation.
   4 *
   5 * This program is free software; you can redistribute it and/or modify it
   6 * under the terms and conditions of the GNU General Public License,
   7 * version 2, as published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope it will be useful, but WITHOUT
  10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12 * more details.
  13 *
  14 */
  15
  16#include <linux/rbtree.h>
  17#include <linux/list.h>
  18
  19#include "util.h"
  20#include "call-path.h"
  21
  22static void call_path__init(struct call_path *cp, struct call_path *parent,
  23                            struct symbol *sym, u64 ip, bool in_kernel)
  24{
  25        cp->parent = parent;
  26        cp->sym = sym;
  27        cp->ip = sym ? 0 : ip;
  28        cp->db_id = 0;
  29        cp->in_kernel = in_kernel;
  30        RB_CLEAR_NODE(&cp->rb_node);
  31        cp->children = RB_ROOT;
  32}
  33
  34struct call_path_root *call_path_root__new(void)
  35{
  36        struct call_path_root *cpr;
  37
  38        cpr = zalloc(sizeof(struct call_path_root));
  39        if (!cpr)
  40                return NULL;
  41        call_path__init(&cpr->call_path, NULL, NULL, 0, false);
  42        INIT_LIST_HEAD(&cpr->blocks);
  43        return cpr;
  44}
  45
  46void call_path_root__free(struct call_path_root *cpr)
  47{
  48        struct call_path_block *pos, *n;
  49
  50        list_for_each_entry_safe(pos, n, &cpr->blocks, node) {
  51                list_del(&pos->node);
  52                free(pos);
  53        }
  54        free(cpr);
  55}
  56
  57static struct call_path *call_path__new(struct call_path_root *cpr,
  58                                        struct call_path *parent,
  59                                        struct symbol *sym, u64 ip,
  60                                        bool in_kernel)
  61{
  62        struct call_path_block *cpb;
  63        struct call_path *cp;
  64        size_t n;
  65
  66        if (cpr->next < cpr->sz) {
  67                cpb = list_last_entry(&cpr->blocks, struct call_path_block,
  68                                      node);
  69        } else {
  70                cpb = zalloc(sizeof(struct call_path_block));
  71                if (!cpb)
  72                        return NULL;
  73                list_add_tail(&cpb->node, &cpr->blocks);
  74                cpr->sz += CALL_PATH_BLOCK_SIZE;
  75        }
  76
  77        n = cpr->next++ & CALL_PATH_BLOCK_MASK;
  78        cp = &cpb->cp[n];
  79
  80        call_path__init(cp, parent, sym, ip, in_kernel);
  81
  82        return cp;
  83}
  84
  85struct call_path *call_path__findnew(struct call_path_root *cpr,
  86                                     struct call_path *parent,
  87                                     struct symbol *sym, u64 ip, u64 ks)
  88{
  89        struct rb_node **p;
  90        struct rb_node *node_parent = NULL;
  91        struct call_path *cp;
  92        bool in_kernel = ip >= ks;
  93
  94        if (sym)
  95                ip = 0;
  96
  97        if (!parent)
  98                return call_path__new(cpr, parent, sym, ip, in_kernel);
  99
 100        p = &parent->children.rb_node;
 101        while (*p != NULL) {
 102                node_parent = *p;
 103                cp = rb_entry(node_parent, struct call_path, rb_node);
 104
 105                if (cp->sym == sym && cp->ip == ip)
 106                        return cp;
 107
 108                if (sym < cp->sym || (sym == cp->sym && ip < cp->ip))
 109                        p = &(*p)->rb_left;
 110                else
 111                        p = &(*p)->rb_right;
 112        }
 113
 114        cp = call_path__new(cpr, parent, sym, ip, in_kernel);
 115        if (!cp)
 116                return NULL;
 117
 118        rb_link_node(&cp->rb_node, node_parent, p);
 119        rb_insert_color(&cp->rb_node, &parent->children);
 120
 121        return cp;
 122}
 123