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
  22 static 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
  34 struct 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
  46 void 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
  57 static 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
  85 struct 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 }