jdk8-mips64-public/hotspot: src/share/vm/utilities/nativeCallStack.hpp@eef07cd490d4

     1 /*

     2  * Copyright (c) 2014, 2018, 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  */

    25 #ifndef SHARE_VM_UTILITIES_NATIVE_CALL_STACK_HPP

    26 #define SHARE_VM_UTILITIES_NATIVE_CALL_STACK_HPP

    28 #include "memory/allocation.hpp"

    29 #include "services/nmtCommon.hpp"

    30 #include "utilities/ostream.hpp"

    32 /*

    33  * This class represents a native call path (does not include Java frame)

    34  *

    35  * This class is developed in the context of native memory tracking, it can

    36  * be an useful tool for debugging purpose.

    37  *

    38  * For example, following code should print out native call path:

    39  *

    40  *   ....

    41  *   NativeCallStack here;

    42  *   here.print_on(tty);

    43  *   ....

    44  *

    45  * However, there are a couple of restrictions on this class. If the restrictions are

    46  * not strictly followed, it may break native memory tracking badly.

    47  *

    48  * 1. Number of stack frames to capture, is defined by native memory tracking.

    49  *    This number has impacts on how much memory to be used by native

    50  *    memory tracking.

    51  * 2. The class is strict stack object, no heap or virtual memory can be allocated

    52  *    from it.

    53  */

    54 class MemTracker;

    56 class NativeCallStack : public StackObj {

    57   friend class MemTracker;

    59 private:

    60   address       _stack[NMT_TrackingStackDepth];

    61   unsigned int  _hash_value;

    63   static NativeCallStack EMPTY_STACK;

    64 public:

    65   NativeCallStack(int toSkip = 0, bool fillStack = false);

    66   NativeCallStack(address* pc, int frameCount);

    68   static inline const NativeCallStack& empty_stack() {

    69     return EMPTY_STACK;

    70   }

    72   // if it is an empty stack

    73   inline bool is_empty() const {

    74     return _stack[0] == NULL;

    75   }

    77   // number of stack frames captured

    78   int frames() const;

    80   inline int compare(const NativeCallStack& other) const {

    81     return memcmp(_stack, other._stack, sizeof(_stack));

    82   }

    84   inline bool equals(const NativeCallStack& other) const {

    85     // compare hash values

    86     if (hash() != other.hash()) return false;

    87     // compare each frame

    88     return compare(other) == 0;

    89   }

    91   inline address get_frame(int index) const {

    92     assert(index >= 0 && index < NMT_TrackingStackDepth, "Index out of bound");

    93     return _stack[index];

    94   }

    96   // Hash code. Any better algorithm?

    97   unsigned int hash() const;

    99   void print_on(outputStream* out) const;

   100   void print_on(outputStream* out, int indent) const;

   101 };

   103 #endif

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