1 /*
   2  * Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that 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
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "runtime/os.hpp"
  27 #include "utilities/globalDefinitions.hpp"
  28 #include "utilities/nativeCallStack.hpp"
  29 
  30 const NativeCallStack NativeCallStack::EMPTY_STACK(0, false);
  31 
  32 NativeCallStack::NativeCallStack(int toSkip, bool fillStack) :
  33   _hash_value(0) {
  34 
  35   if (fillStack) {
  36     os::get_native_stack(_stack, NMT_TrackingStackDepth, toSkip);
  37   } else {
  38     for (int index = 0; index < NMT_TrackingStackDepth; index ++) {
  39       _stack[index] = NULL;
  40     }
  41   }
  42 }
  43 
  44 NativeCallStack::NativeCallStack(address* pc, int frameCount) {
  45   int frameToCopy = (frameCount < NMT_TrackingStackDepth) ?
  46     frameCount : NMT_TrackingStackDepth;
  47   int index;
  48   for (index = 0; index < frameToCopy; index ++) {
  49     _stack[index] = pc[index];
  50   }
  51   for (; index < NMT_TrackingStackDepth; index ++) {
  52     _stack[index] = NULL;
  53   }
  54   _hash_value = 0;
  55 }
  56 
  57 // number of stack frames captured
  58 int NativeCallStack::frames() const {
  59   int index;
  60   for (index = 0; index < NMT_TrackingStackDepth; index ++) {
  61     if (_stack[index] == NULL) {
  62       break;
  63     }
  64   }
  65   return index;
  66 }
  67 
  68 // Hash code. Any better algorithm?
  69 unsigned int NativeCallStack::hash() const {
  70   uintptr_t hash_val = _hash_value;
  71   if (hash_val == 0) {
  72     for (int index = 0; index < NMT_TrackingStackDepth; index++) {
  73       if (_stack[index] == NULL) break;
  74       hash_val += (uintptr_t)_stack[index];
  75     }
  76 
  77     NativeCallStack* p = const_cast<NativeCallStack*>(this);
  78     p->_hash_value = (unsigned int)(hash_val & 0xFFFFFFFF);
  79   }
  80   return _hash_value;
  81 }
  82 
  83 void NativeCallStack::print_on(outputStream* out) const {
  84   print_on(out, 0);
  85 }
  86 
  87 // Decode and print this call path
  88 void NativeCallStack::print_on(outputStream* out, int indent) const {
  89   address pc;
  90   char    buf[1024];
  91   int     offset;
  92   if (is_empty()) {
  93     for (int index = 0; index < indent; index ++) out->print(" ");
  94     out->print("[BOOTSTRAP]");
  95   } else {
  96     for (int frame = 0; frame < NMT_TrackingStackDepth; frame ++) {
  97       pc = get_frame(frame);
  98       if (pc == NULL) break;
  99       // Print indent
 100       for (int index = 0; index < indent; index ++) out->print(" ");
 101       if (os::dll_address_to_function_name(pc, buf, sizeof(buf), &offset)) {
 102         out->print_cr("[" PTR_FORMAT "] %s+0x%x", p2i(pc), buf, offset);
 103       } else {
 104         out->print_cr("[" PTR_FORMAT "]", p2i(pc));
 105       }
 106     }
 107   }
 108 }
 109