1 /*

     2  * Copyright (c) 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 "classfile/classLoaderData.hpp"

    26 #include "classfile/classLoaderDataGraph.hpp"

    27 #include "gc/z/zAddress.hpp"

    28 #include "gc/z/zHeap.inline.hpp"

    29 #include "gc/z/zOop.hpp"

    30 #include "gc/z/zResurrection.hpp"

    31 #include "gc/z/zRootsIterator.hpp"

    32 #include "gc/z/zStat.hpp"

    33 #include "gc/z/zVerify.hpp"

    34 #include "memory/allocation.hpp"

    35 #include "memory/iterator.inline.hpp"

    36 #include "oops/oop.inline.hpp"

    37 

    38 #define BAD_OOP_REPORT(addr)                                                \

    39     "Bad oop " PTR_FORMAT " found at " PTR_FORMAT ", expected " PTR_FORMAT, \

    40     addr, p2i(p), ZAddress::good(addr)

    41 

    42 class ZVerifyRootsClosure : public ZRootsIteratorClosure {

    43 public:

    44   virtual void do_oop(oop* p) {

    45     uintptr_t value = ZOop::to_address(*p);

    46 

    47     if (value == 0) {

    48       return;

    49     }

    50 

    51     guarantee(!ZAddress::is_finalizable(value), BAD_OOP_REPORT(value));

    52     guarantee(ZAddress::is_good(value), BAD_OOP_REPORT(value));

    53     guarantee(oopDesc::is_oop(ZOop::from_address(value)), BAD_OOP_REPORT(value));

    54   }

    55   virtual void do_oop(narrowOop*) { ShouldNotReachHere(); }

    56 };

    57 

    58 template <bool VisitReferents>

    59 class ZVerifyOopClosure : public ClaimMetadataVisitingOopIterateClosure, public ZRootsIteratorClosure  {

    60 public:

    61   ZVerifyOopClosure() :

    62       ClaimMetadataVisitingOopIterateClosure(ClassLoaderData::_claim_other) {}

    63 

    64   virtual void do_oop(oop* p);

    65   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }

    66 

    67   virtual ReferenceIterationMode reference_iteration_mode() {

    68     return VisitReferents ? DO_FIELDS : DO_FIELDS_EXCEPT_REFERENT;

    69   }

    70 

    71 #ifdef ASSERT

    72   // Verification handled by the closure itself

    73   virtual bool should_verify_oops() {

    74     return false;

    75   }

    76 #endif

    77 };

    78 

    79 class ZVerifyObjectClosure : public ObjectClosure {

    80 private:

    81   bool _visit_referents;

    82 

    83 public:

    84   ZVerifyObjectClosure(bool visit_referents) : _visit_referents(visit_referents) {}

    85   virtual void do_object(oop o);

    86 };

    87 

    88 template <typename RootsIterator>

    89 void ZVerify::roots_impl() {

    90   if (ZVerifyRoots) {

    91     ZVerifyRootsClosure cl;

    92     RootsIterator iter;

    93     iter.oops_do(&cl);

    94   }

    95 }

    96 

    97 void ZVerify::roots_strong() {

    98   roots_impl<ZRootsIterator>();

    99 }

   100 

   101 class ZVerifyConcurrentRootsIterator : public ZConcurrentRootsIterator {

   102 public:

   103   ZVerifyConcurrentRootsIterator()

   104       : ZConcurrentRootsIterator(ClassLoaderData::_claim_none) {}

   105 };

   106 

   107 void ZVerify::roots_concurrent() {

   108   roots_impl<ZVerifyConcurrentRootsIterator>();

   109 }

   110 

   111 void ZVerify::roots_weak() {

   112   assert(!ZResurrection::is_blocked(), "Invalid phase");

   113 

   114   roots_impl<ZWeakRootsIterator>();

   115 }

   116 

   117 void ZVerify::roots(bool verify_weaks) {

   118   roots_strong();

   119   roots_concurrent();

   120   if (verify_weaks) {

   121     roots_weak();

   122     roots_concurrent_weak();

   123   }

   124 }

   125 

   126 void ZVerify::objects(bool verify_weaks) {

   127   if (ZVerifyObjects) {

   128     ZVerifyObjectClosure cl(verify_weaks);

   129     ZHeap::heap()->object_iterate(&cl, verify_weaks);

   130   }

   131 }

   132 

   133 void ZVerify::roots_concurrent_weak() {

   134   assert(!ZResurrection::is_blocked(), "Invalid phase");

   135 

   136   roots_impl<ZConcurrentWeakRootsIterator>();

   137 }

   138 

   139 void ZVerify::roots_and_objects(bool verify_weaks) {

   140   ZStatTimerDisable  _disable;

   141 

   142   roots(verify_weaks);

   143   objects(verify_weaks);

   144 }

   145 

   146 void ZVerify::after_mark() {

   147   // Only verify strong roots and references.

   148   roots_and_objects(false /* verify_weaks */);

   149 }

   150 

   151 void ZVerify::after_weak_processing() {

   152   // Also verify weaks - all should have been processed at this point.

   153   roots_and_objects(true /* verify_weaks */);

   154 }

   155 

   156 template <bool VisitReferents>

   157 void ZVerifyOopClosure<VisitReferents>::do_oop(oop* p) {

   158   guarantee(SafepointSynchronize::is_at_safepoint(), "Must be at a safepoint");

   159   guarantee(ZGlobalPhase == ZPhaseMarkCompleted, "Invalid phase");

   160   guarantee(!ZResurrection::is_blocked(), "Invalid phase");

   161 

   162   const oop o = RawAccess<>::oop_load(p);

   163   if (o == NULL) {

   164     return;

   165   }

   166 

   167   const uintptr_t addr = ZOop::to_address(o);

   168   if (VisitReferents) {

   169     guarantee(ZAddress::is_good(addr) || ZAddress::is_finalizable_good(addr), BAD_OOP_REPORT(addr));

   170   } else {

   171     // Should not encounter finalizable oops through strong-only paths. Assumes only strong roots are visited.

   172     guarantee(ZAddress::is_good(addr), BAD_OOP_REPORT(addr));

   173   }

   174 

   175   const uintptr_t good_addr = ZAddress::good(addr);

   176   guarantee(oopDesc::is_oop(ZOop::from_address(good_addr)), BAD_OOP_REPORT(addr));

   177 }

   178 

   179 void ZVerifyObjectClosure::do_object(oop o) {

   180   if (_visit_referents) {

   181     ZVerifyOopClosure<true /* VisitReferents */> cl;

   182     o->oop_iterate((OopIterateClosure*)&cl);

   183   } else {

   184     ZVerifyOopClosure<false /* VisitReferents */> cl;

   185     o->oop_iterate(&cl);

   186   }

   187 }