1 /*

     2  * Copyright (c) 1997, 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  */

    24 

    25 #ifndef SHARE_VM_RUNTIME_DTRACEJSDT_HPP

    26 #define SHARE_VM_RUNTIME_DTRACEJSDT_HPP

    27 

    28 #include "code/nmethod.hpp"

    29 

    30 class RegisteredProbes;

    31 typedef jlong OpaqueProbes;

    32 

    33 class DTraceJSDT : AllStatic {

    34  private:

    35 

    36   static int pd_activate(void* moduleBaseAddress, jstring module,

    37       jint providers_count, JVM_DTraceProvider* providers);

    38   static void pd_dispose(int handle);

    39   static jboolean pd_is_supported();

    40 

    41  public:

    42 

    43   static OpaqueProbes activate(

    44       jint version, jstring module_name, jint providers_count,

    45       JVM_DTraceProvider* providers, TRAPS);

    46   static jboolean is_probe_enabled(jmethodID method);

    47   static void dispose(OpaqueProbes handle);

    48   static jboolean is_supported();

    49 };

    50 

    51 class RegisteredProbes : public CHeapObj<mtInternal> {

    52  private:

    53   nmethod** _nmethods;      // all the probe methods

    54   size_t    _count;         // number of probe methods

    55   int       _helper_handle; // DTrace-assigned identifier

    56 

    57  public:

    58   RegisteredProbes(size_t count) {

    59     _count = count;

    60     _nmethods = NEW_C_HEAP_ARRAY(nmethod*, count, mtInternal);

    61   }

    62 

    63   ~RegisteredProbes() {

    64     for (size_t i = 0; i < _count; ++i) {

    65       // Let the sweeper reclaim it

    66       _nmethods[i]->make_not_entrant();

    67       _nmethods[i]->method()->clear_code();

    68     }

    69     FREE_C_HEAP_ARRAY(nmethod*, _nmethods);

    70     _nmethods = NULL;

    71     _count = 0;

    72   }

    73 

    74   static RegisteredProbes* toRegisteredProbes(OpaqueProbes p) {

    75     return (RegisteredProbes*)(intptr_t)p;

    76   }

    77 

    78   static OpaqueProbes toOpaqueProbes(RegisteredProbes* p) {

    79     return (OpaqueProbes)(intptr_t)p;

    80   }

    81 

    82   void set_helper_handle(int handle) { _helper_handle = handle; }

    83   int helper_handle() const { return _helper_handle; }

    84 

    85   nmethod* nmethod_at(size_t i) {

    86     assert(i >= 0 && i < _count, "bad nmethod index");

    87     return _nmethods[i];

    88   }

    89 

    90   void nmethod_at_put(size_t i, nmethod* nm) {

    91     assert(i >= 0 && i < _count, "bad nmethod index");

    92     _nmethods[i] = nm;

    93   }

    94 };

    95 

    96 #endif // SHARE_VM_RUNTIME_DTRACEJSDT_HPP