1 /*
   2  * Copyright (c) 2015, 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 #include "precompiled.hpp"
  25 #include "gc/z/zAddress.inline.hpp"
  26 #include "gc/z/zBarrier.inline.hpp"
  27 #include "gc/z/zHeap.hpp"
  28 #include "gc/z/zOopClosures.inline.hpp"
  29 #include "gc/z/zPage.hpp"
  30 #include "gc/z/zRelocate.hpp"
  31 #include "gc/z/zRelocationSet.inline.hpp"
  32 #include "gc/z/zRootsIterator.hpp"
  33 #include "gc/z/zTask.hpp"
  34 #include "gc/z/zThreadLocalAllocBuffer.hpp"
  35 #include "gc/z/zWorkers.hpp"
  36 
  37 ZRelocate::ZRelocate(ZWorkers* workers) :
  38     _workers(workers) {}
  39 
  40 class ZRelocateRootsIteratorClosure : public ZRootsIteratorClosure {
  41 public:
  42   virtual void do_thread(Thread* thread) {
  43     ZRootsIteratorClosure::do_thread(thread);
  44 
  45     // Update thread local address bad mask
  46     ZThreadLocalData::set_address_bad_mask(thread, ZAddressBadMask);
  47 
  48     // Remap TLAB
  49     ZThreadLocalAllocBuffer::remap(thread);
  50   }
  51 
  52   virtual void do_oop(oop* p) {
  53     ZBarrier::relocate_barrier_on_root_oop_field(p);
  54   }
  55 
  56   virtual void do_oop(narrowOop* p) {
  57     ShouldNotReachHere();
  58   }
  59 };
  60 
  61 class ZRelocateRootsTask : public ZTask {
  62 private:
  63   ZRootsIterator                _roots;
  64   ZRelocateRootsIteratorClosure _cl;
  65 
  66 public:
  67   ZRelocateRootsTask() :
  68       ZTask("ZRelocateRootsTask"),
  69       _roots() {}
  70 
  71   virtual void work() {
  72     // During relocation we need to visit the JVMTI
  73     // export weak roots to rehash the JVMTI tag map
  74     _roots.oops_do(&_cl, true /* visit_jvmti_weak_export */);
  75   }
  76 };
  77 
  78 void ZRelocate::start() {
  79   ZRelocateRootsTask task;
  80   _workers->run_parallel(&task);
  81 }
  82 
  83 class ZRelocateObjectClosure : public ObjectClosure {
  84 private:
  85   ZPage* const _page;
  86 
  87 public:
  88   ZRelocateObjectClosure(ZPage* page) :
  89       _page(page) {}
  90 
  91   virtual void do_object(oop o) {
  92     _page->relocate_object(ZOop::to_address(o));
  93   }
  94 };
  95 
  96 bool ZRelocate::work(ZRelocationSetParallelIterator* iter) {
  97   bool success = true;
  98 
  99   // Relocate pages in the relocation set
 100   for (ZPage* page; iter->next(&page);) {
 101     // Relocate objects in page
 102     ZRelocateObjectClosure cl(page);
 103     page->object_iterate(&cl);
 104 
 105     if (ZVerifyForwarding) {
 106       page->verify_forwarding();
 107     }
 108 
 109     if (page->is_pinned()) {
 110       // Relocation failed, page is now pinned
 111       success = false;
 112     } else {
 113       // Relocation succeeded, release page
 114       ZHeap::heap()->release_page(page, true /* reclaimed */);
 115     }
 116   }
 117 
 118   return success;
 119 }
 120 
 121 class ZRelocateTask : public ZTask {
 122 private:
 123   ZRelocate* const               _relocate;
 124   ZRelocationSetParallelIterator _iter;
 125   bool                           _failed;
 126 
 127 public:
 128   ZRelocateTask(ZRelocate* relocate, ZRelocationSet* relocation_set) :
 129       ZTask("ZRelocateTask"),
 130       _relocate(relocate),
 131       _iter(relocation_set),
 132       _failed(false) {}
 133 
 134   virtual void work() {
 135     if (!_relocate->work(&_iter)) {
 136       _failed = true;
 137     }
 138   }
 139 
 140   bool failed() const {
 141     return _failed;
 142   }
 143 };
 144 
 145 bool ZRelocate::relocate(ZRelocationSet* relocation_set) {
 146   ZRelocateTask task(this, relocation_set);
 147   _workers->run_concurrent(&task);
 148   return !task.failed();
 149 }