1 /*

     2  * Copyright 1997-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    20  * CA 95054 USA or visit www.sun.com if you need additional information or

    21  * have any questions.

    22  *

    23  */

    24 

    25 class RegisteredProbes;

    26 typedef jlong OpaqueProbes;

    27 

    28 class DTraceJSDT : AllStatic {

    29  private:

    30 

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

    32       jint providers_count, JVM_DTraceProvider* providers);

    33   static void pd_dispose(int handle);

    34   static jboolean pd_is_supported();

    35 

    36  public:

    37 

    38   static OpaqueProbes activate(

    39       jint version, jstring module_name, jint providers_count,

    40       JVM_DTraceProvider* providers, TRAPS);

    41   static jboolean is_probe_enabled(jmethodID method);

    42   static void dispose(OpaqueProbes handle);

    43   static jboolean is_supported();

    44 };

    45 

    46 class RegisteredProbes : public CHeapObj {

    47  private:

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

    49   size_t    _count;         // number of probe methods

    50   int       _helper_handle; // DTrace-assigned identifier

    51 

    52  public:

    53   RegisteredProbes(size_t count) {

    54     _count = count;

    55     _nmethods = NEW_C_HEAP_ARRAY(nmethod*, count);

    56   }

    57 

    58   ~RegisteredProbes() {

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

    60       // Let the sweeper reclaim it

    61       _nmethods[i]->make_not_entrant();

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

    63     }

    64     FREE_C_HEAP_ARRAY(nmethod*, _nmethods);

    65     _nmethods = NULL;

    66     _count = 0;

    67   }

    68 

    69   static RegisteredProbes* toRegisteredProbes(OpaqueProbes p) {

    70     return (RegisteredProbes*)(intptr_t)p;

    71   }

    72 

    73   static OpaqueProbes toOpaqueProbes(RegisteredProbes* p) {

    74     return (OpaqueProbes)(intptr_t)p;

    75   }

    76 

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

    78   int helper_handle() const { return _helper_handle; }

    79 

    80   nmethod* nmethod_at(size_t i) {

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

    82     return _nmethods[i];

    83   }

    84 

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

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

    87     _nmethods[i] = nm;

    88   }

    89 };