jdk8-mips64-public/hotspot: src/share/vm/utilities/nativeCallStack.hpp@c6211b707068

8055007: NMT2: emptyStack missing in minimal build
Summary: Refactored emptyStack to a static member of NativeCallStack, which is accessible in minimal build.
Reviewed-by: coleenp, dholmes

     1 /*

     2  * Copyright (c) 2014, 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 NativeCallStack : public StackObj {

    55  public:

    56   static const NativeCallStack EMPTY_STACK;

    58  private:

    59   address   _stack[NMT_TrackingStackDepth];

    60   int       _hash_value;

    62  public:

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

    64   NativeCallStack(address* pc, int frameCount);

    67   // if it is an empty stack

    68   inline bool is_empty() const {

    69     return _stack[0] == NULL;

    70   }

    72   // number of stack frames captured

    73   int frames() const;

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

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

    77   }

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

    80     // compare hash values

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

    82     // compare each frame

    83     return compare(other) == 0;

    84   }

    86   inline address get_frame(int index) const {

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

    88     return _stack[index];

    89   }

    91   // Hash code. Any better algorithm?

    92   int hash() const;

    94   void print_on(outputStream* out) const;

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

    96 };

    98 #endif

Mercurial > jdk8-mips64-public > hotspot / file revision

src/share/vm/utilities/nativeCallStack.hpp@c6211b707068

src/share/vm/utilities/nativeCallStack.hpp