1 
   2 /*
   3  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
  22  * questions.
  23  *
  24  */
  25 
  26 #include "precompiled.hpp"
  27 #include "gc_implementation/parallelScavenge/gcTaskManager.hpp"
  28 #include "gc_implementation/parallelScavenge/gcTaskThread.hpp"
  29 #include "memory/allocation.hpp"
  30 #include "memory/allocation.inline.hpp"
  31 #include "memory/resourceArea.hpp"
  32 #include "runtime/handles.hpp"
  33 #include "runtime/handles.inline.hpp"
  34 #include "runtime/os.hpp"
  35 #include "runtime/thread.hpp"
  36 
  37 GCTaskThread::GCTaskThread(GCTaskManager* manager,
  38                            uint           which,
  39                            uint           processor_id) :
  40   _manager(manager),
  41   _processor_id(processor_id),
  42   _time_stamps(NULL),
  43   _time_stamp_index(0)
  44 {
  45   if (!os::create_thread(this, os::pgc_thread))
  46     vm_exit_out_of_memory(0, "Cannot create GC thread. Out of system resources.");
  47 
  48   if (PrintGCTaskTimeStamps) {
  49     _time_stamps = NEW_C_HEAP_ARRAY(GCTaskTimeStamp, GCTaskTimeStampEntries );
  50 
  51     guarantee(_time_stamps != NULL, "Sanity");
  52   }
  53   set_id(which);
  54   set_name("GC task thread#%d (ParallelGC)", which);
  55 }
  56 
  57 GCTaskThread::~GCTaskThread() {
  58   if (_time_stamps != NULL) {
  59     FREE_C_HEAP_ARRAY(GCTaskTimeStamp, _time_stamps);
  60   }
  61 }
  62 
  63 void GCTaskThread::start() {
  64   os::start_thread(this);
  65 }
  66 
  67 GCTaskTimeStamp* GCTaskThread::time_stamp_at(uint index) {
  68   guarantee(index < GCTaskTimeStampEntries, "increase GCTaskTimeStampEntries");
  69 
  70   return &(_time_stamps[index]);
  71 }
  72 
  73 void GCTaskThread::print_task_time_stamps() {
  74   assert(PrintGCTaskTimeStamps, "Sanity");
  75   assert(_time_stamps != NULL, "Sanity (Probably set PrintGCTaskTimeStamps late)");
  76 
  77   tty->print_cr("GC-Thread %u entries: %d", id(), _time_stamp_index);
  78   for(uint i=0; i<_time_stamp_index; i++) {
  79     GCTaskTimeStamp* time_stamp = time_stamp_at(i);
  80     tty->print_cr("\t[ %s " INT64_FORMAT " " INT64_FORMAT " ]",
  81                   time_stamp->name(),
  82                   time_stamp->entry_time(),
  83                   time_stamp->exit_time());
  84   }
  85 
  86   // Reset after dumping the data
  87   _time_stamp_index = 0;
  88 }
  89 
  90 void GCTaskThread::print_on(outputStream* st) const {
  91   st->print("\"%s\" ", name());
  92   Thread::print_on(st);
  93   st->cr();
  94 }
  95 
  96 void GCTaskThread::run() {
  97   // Set up the thread for stack overflow support
  98   this->record_stack_base_and_size();
  99   this->initialize_thread_local_storage();
 100   // Bind yourself to your processor.
 101   if (processor_id() != GCTaskManager::sentinel_worker()) {
 102     if (TraceGCTaskThread) {
 103       tty->print_cr("GCTaskThread::run: "
 104                     "  binding to processor %u", processor_id());
 105     }
 106     if (!os::bind_to_processor(processor_id())) {
 107       DEBUG_ONLY(
 108         warning("Couldn't bind GCTaskThread %u to processor %u",
 109                       which(), processor_id());
 110       )
 111     }
 112   }
 113   // Part of thread setup.
 114   // ??? Are these set up once here to make subsequent ones fast?
 115   HandleMark   hm_outer;
 116   ResourceMark rm_outer;
 117 
 118   TimeStamp timer;
 119 
 120   for (;/* ever */;) {
 121     // These are so we can flush the resources allocated in the inner loop.
 122     HandleMark   hm_inner;
 123     ResourceMark rm_inner;
 124     for (; /* break */; ) {
 125       // This will block until there is a task to be gotten.
 126       GCTask* task = manager()->get_task(which());
 127 
 128       // In case the update is costly
 129       if (PrintGCTaskTimeStamps) {
 130         timer.update();
 131       }
 132 
 133       jlong entry_time = timer.ticks();
 134       char* name = task->name();
 135 
 136       task->do_it(manager(), which());
 137       manager()->note_completion(which());
 138 
 139       if (PrintGCTaskTimeStamps) {
 140         assert(_time_stamps != NULL, "Sanity (PrintGCTaskTimeStamps set late?)");
 141 
 142         timer.update();
 143 
 144         GCTaskTimeStamp* time_stamp = time_stamp_at(_time_stamp_index++);
 145 
 146         time_stamp->set_name(name);
 147         time_stamp->set_entry_time(entry_time);
 148         time_stamp->set_exit_time(timer.ticks());
 149       }
 150 
 151       // Check if we should release our inner resources.
 152       if (manager()->should_release_resources(which())) {
 153         manager()->note_release(which());
 154         break;
 155       }
 156     }
 157   }
 158 }