1 /*

     2  * Copyright (c) 2018, 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 

    26 #include "logging/log.hpp"

    27 #include "memory/metaspace.hpp"

    28 #include "memory/metaspace/chunkAllocSequence.hpp"

    29 #include "memory/metaspace/classLoaderMetaspace.hpp"

    30 #include "memory/metaspace/metaspaceCommon.hpp"

    31 #include "runtime/atomic.hpp"

    32 #include "utilities/debug.hpp"

    33 

    34 namespace metaspace {

    35 

    36 ClassLoaderMetaspace::ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType space_type)

    37   : _lock(lock)

    38   , _space_type(space_type)

    39   , _non_class_space_manager(NULL)

    40   , _class_space_manager(NULL)

    41 {

    42   DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_metaspace_births));

    43 

    44   // Initialize non-class spacemanager

    45   _non_class_space_manager = new SpaceManager(

    46       Metaspace::chunk_manager_metadata(),

    47       ChunkAllocSequence::alloc_sequence_by_space_type(space_type, false),

    48       lock);

    49 

    50   // If needed, initialize class spacemanager

    51   if (Metaspace::using_class_space()) {

    52     _class_space_manager = new SpaceManager(

    53         Metaspace::chunk_manager_class(),

    54         ChunkAllocSequence::alloc_sequence_by_space_type(space_type, true),

    55         lock);

    56   }

    57 

    58 }

    59 

    60 ClassLoaderMetaspace::~ClassLoaderMetaspace() {

    61   Metaspace::assert_not_frozen();

    62   DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_metaspace_deaths));

    63   delete _non_class_space_manager;

    64   delete _class_space_manager;

    65 }

    66 

    67 // Allocate word_size words from Metaspace.

    68 MetaWord* ClassLoaderMetaspace::allocate(size_t word_size, bool is_class) {

    69   Metaspace::assert_not_frozen();

    70   DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_allocs));

    71   if (is_class && Metaspace::using_class_space()) {

    72     return class_space_manager()->allocate(word_size);

    73   } else {

    74     return non_class_space_manager()->allocate(word_size);

    75   }

    76 }

    77 

    78 // Attempt to expand the GC threshold to be good for at least another word_size words

    79 // and allocate. Returns NULL if failure. Used during Metaspace GC.

    80 MetaWord* ClassLoaderMetaspace::expand_GC_threshold_and_allocate(size_t word_size, bool is_class) {

    81   Metaspace::assert_not_frozen();

    82   size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);

    83   assert(delta_bytes > 0, "Must be");

    84 

    85   size_t before = 0;

    86   size_t after = 0;

    87   bool can_retry = true;

    88   MetaWord* res;

    89   bool incremented;

    90 

    91   // Each thread increments the HWM at most once. Even if the thread fails to increment

    92   // the HWM, an allocation is still attempted. This is because another thread must then

    93   // have incremented the HWM and therefore the allocation might still succeed.

    94   do {

    95     incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before, &can_retry);

    96     res = allocate(word_size, is_class);

    97   } while (!incremented && res == NULL && can_retry);

    98 

    99   if (incremented) {

   100     Metaspace::tracer()->report_gc_threshold(before, after,

   101                                   MetaspaceGCThresholdUpdater::ExpandAndAllocate);

   102     log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after);

   103   }

   104 

   105   return res;

   106 }

   107 

   108 // Prematurely returns a metaspace allocation to the _block_freelists

   109 // because it is not needed anymore.

   110 void ClassLoaderMetaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {

   111 

   112   Metaspace::assert_not_frozen();

   113   DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_external_deallocs));

   114 

   115   if (is_class && Metaspace::using_class_space()) {

   116     class_space_manager()->deallocate(ptr, word_size);

   117   } else {

   118     non_class_space_manager()->deallocate(ptr, word_size);

   119   }

   120 

   121 }

   122 

   123 

   124 

   125 

   126 

   127 

   128