1 /*
   2  * Copyright (c) 2012, 2019, 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 "jfr/utilities/jfrTraceTime.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   void set_starttime(const JfrTraceTime& time) {
  51     _startTime = time;
  52   }
  53 
  54   void set_endtime(const JfrTraceTime& time) {
  55     _endTime = time;
  56   }
  57 
  58   TraceEvent(EventStartTime timing=TIMED) :
  59     _startTime(0),
  60     _endTime(0),
  61     _started(false)
  62 #ifdef ASSERT
  63     , _committed(false)
  64 #endif
  65   {
  66     if (T::is_enabled()) {
  67       _started = true;
  68       if (TIMED == timing && !T::isInstant) {
  69         static_cast<T*>(this)->set_starttime(Tracing::time());
  70       }
  71     }
  72   }
  73  public:
  74   void set_starttime(const Ticks& time) {
  75     _startTime = time.value();
  76   }
  77 
  78   void set_endtime(const Ticks& time) {
  79     _endTime = time.value();
  80   }
  81 
  82   static bool is_enabled() {
  83     return EnableJFR && Tracing::is_event_enabled(T::eventId);
  84   }
  85 
  86   bool should_commit() {
  87     return _started;
  88   }
  89 
  90   void commit() {
  91     if (!should_commit()) {
  92       return;
  93     }
  94     assert(!_committed, "event already committed");
  95     if (_startTime == 0) {
  96       static_cast<T*>(this)->set_starttime(Tracing::time());
  97     } else if (_endTime == 0) {
  98       static_cast<T*>(this)->set_endtime(Tracing::time());
  99     }
 100     if (static_cast<T*>(this)->should_write()) {
 101       static_cast<T*>(this)->writeEvent();
 102       DEBUG_ONLY(_committed = true;)
 103     }
 104   }
 105 
 106   static TraceEventId id() {
 107     return T::eventId;
 108   }
 109 
 110   static bool is_instant() {
 111     return T::isInstant;
 112   }
 113 
 114   static bool is_requestable() {
 115     return T::isRequestable;
 116   }
 117 
 118   static bool has_thread() {
 119     return T::hasThread;
 120   }
 121 
 122   static bool has_stacktrace() {
 123     return T::hasStackTrace;
 124   }
 125 };
 126 
 127 #endif // INCLUDE_TRACE
 128 #endif // SHARE_VM_TRACE_TRACEEVENT_HPP