1 /*
   2  * Copyright (c) 2012, 2017, 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_TRACE_TRACEEVENT_HPP
  26 #define SHARE_VM_TRACE_TRACEEVENT_HPP
  27 
  28 #include "trace/traceTime.hpp"
  29 #include "utilities/macros.hpp"
  30 
  31 enum EventStartTime {
  32   UNTIMED,
  33   TIMED
  34 };
  35 
  36 #if INCLUDE_TRACE
  37 #include "trace/traceBackend.hpp"
  38 #include "tracefiles/traceEventIds.hpp"
  39 #include "utilities/ticks.hpp"
  40 
  41 template<typename T>
  42 class TraceEvent {
  43  private:
  44   bool _started;
  45 
  46  protected:
  47   jlong _startTime;
  48   jlong _endTime;
  49   DEBUG_ONLY(bool _committed;)
  50 
  51   void set_starttime(const TracingTime& time) {
  52     _startTime = time;
  53   }
  54 
  55   void set_endtime(const TracingTime& time) {
  56     _endTime = time;
  57   }
  58 
  59   TraceEvent(EventStartTime timing=TIMED) :
  60     _startTime(0),
  61     _endTime(0),
  62     _started(false)
  63 #ifdef ASSERT
  64     , _committed(false)
  65 #endif
  66   {
  67     if (T::is_enabled()) {
  68       _started = true;
  69       if (TIMED == timing && !T::isInstant) {
  70         static_cast<T*>(this)->set_starttime(Tracing::time());
  71       }
  72     }
  73   }
  74 
  75  public:
  76   void set_starttime(const Ticks& time) {
  77     _startTime = time.value();
  78   }
  79 
  80   void set_endtime(const Ticks& time) {
  81     _endTime = time.value();
  82   }
  83 
  84   static bool is_enabled() {
  85     return Tracing::is_event_enabled(T::eventId);
  86   }
  87 
  88   bool should_commit() {
  89     return _started;
  90   }
  91 
  92   void commit() {
  93     if (!should_commit()) {
  94       return;
  95     }
  96     assert(!_committed, "event already committed");
  97     if (_startTime == 0) {
  98       static_cast<T*>(this)->set_starttime(Tracing::time());
  99     } else if (_endTime == 0) {
 100       static_cast<T*>(this)->set_endtime(Tracing::time());
 101     }
 102     if (static_cast<T*>(this)->should_write()) {
 103       static_cast<T*>(this)->writeEvent();
 104       DEBUG_ONLY(_committed = true;)
 105     }
 106   }
 107 
 108   static TraceEventId id() {
 109     return T::eventId;
 110   }
 111 
 112   static bool is_instant() {
 113     return T::isInstant;
 114   }
 115 
 116   static bool is_requestable() {
 117     return T::isRequestable;
 118   }
 119 
 120   static bool has_thread() {
 121     return T::hasThread;
 122   }
 123 
 124   static bool has_stacktrace() {
 125     return T::hasStackTrace;
 126   }
 127 };
 128 
 129 #endif // INCLUDE_TRACE
 130 #endif // SHARE_VM_TRACE_TRACEEVENT_HPP