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src/hotspot/share/memory/metaspace/metachunk.cpp

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rev 57625 : [mq]: metaspace-improvement


   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 #include "precompiled.hpp"
  26 #include "memory/allocation.hpp"



  27 #include "memory/metaspace/metachunk.hpp"
  28 #include "memory/metaspace/occupancyMap.hpp"
  29 #include "memory/metaspace/virtualSpaceNode.hpp"

  30 #include "utilities/align.hpp"
  31 #include "utilities/copy.hpp"
  32 #include "utilities/debug.hpp"
  33 
  34 namespace metaspace {
  35 
  36 size_t Metachunk::object_alignment() {
  37   // Must align pointers and sizes to 8,
  38   // so that 64 bit types get correctly aligned.
  39   const size_t alignment = 8;
  40 
  41   // Make sure that the Klass alignment also agree.
  42   STATIC_ASSERT(alignment == (size_t)KlassAlignmentInBytes);
  43 
  44   return alignment;
  45 }
  46 
  47 size_t Metachunk::overhead() {
  48   return align_up(sizeof(Metachunk), object_alignment()) / BytesPerWord;
  49 }
  50 
  51 // Metachunk methods
  52 
  53 Metachunk::Metachunk(ChunkIndex chunktype, bool is_class, size_t word_size,
  54                      VirtualSpaceNode* container)
  55     : Metabase<Metachunk>(word_size),
  56     _container(container),
  57     _top(NULL),
  58     _sentinel(CHUNK_SENTINEL),
  59     _chunk_type(chunktype),
  60     _is_class(is_class),
  61     _origin(origin_normal),
  62     _use_count(0)
  63 {
  64   _top = initial_top();
  65   set_is_tagged_free(false);
  66 #ifdef ASSERT
  67   mangle(uninitMetaWordVal);
  68   verify();
  69 #endif
  70 }
  71 
  72 MetaWord* Metachunk::allocate(size_t word_size) {
  73   MetaWord* result = NULL;
  74   // If available, bump the pointer to allocate.
  75   if (free_word_size() >= word_size) {
  76     result = _top;
  77     _top = _top + word_size;
















  78   }
  79   return result;








  80 }
  81 
  82 // _bottom points to the start of the chunk including the overhead.
  83 size_t Metachunk::used_word_size() const {
  84   return pointer_delta(_top, bottom(), sizeof(MetaWord));











  85 }
  86 
  87 size_t Metachunk::free_word_size() const {
  88   return pointer_delta(end(), _top, sizeof(MetaWord));











  89 }
  90 
  91 void Metachunk::print_on(outputStream* st) const {
  92   st->print_cr("Metachunk:"
  93                " bottom " PTR_FORMAT " top " PTR_FORMAT
  94                " end " PTR_FORMAT " size " SIZE_FORMAT " (%s)",
  95                p2i(bottom()), p2i(_top), p2i(end()), word_size(),
  96                chunk_size_name(get_chunk_type()));
  97   if (Verbose) {
  98     st->print_cr("    used " SIZE_FORMAT " free " SIZE_FORMAT,
  99                  used_word_size(), free_word_size());










 100   }














 101 }
 102 
 103 #ifdef ASSERT
 104 void Metachunk::mangle(juint word_value) {
 105   // Overwrite the payload of the chunk and not the links that
 106   // maintain list of chunks.
 107   HeapWord* start = (HeapWord*)initial_top();
 108   size_t size = word_size() - overhead();
 109   Copy::fill_to_words(start, size, word_value);
 110 }
 111 
 112 void Metachunk::verify() const {
 113   assert(is_valid_sentinel(), "Chunk " PTR_FORMAT ": sentinel invalid", p2i(this));
 114   const ChunkIndex chunk_type = get_chunk_type();
 115   assert(is_valid_chunktype(chunk_type), "Chunk " PTR_FORMAT ": Invalid chunk type.", p2i(this));
 116   if (chunk_type != HumongousIndex) {
 117     assert(word_size() == get_size_for_nonhumongous_chunktype(chunk_type, is_class()),
 118            "Chunk " PTR_FORMAT ": wordsize " SIZE_FORMAT " does not fit chunk type %s.",
 119            p2i(this), word_size(), chunk_size_name(chunk_type));
 120   }
 121   assert(is_valid_chunkorigin(get_origin()), "Chunk " PTR_FORMAT ": Invalid chunk origin.", p2i(this));
 122   assert(bottom() <= _top && _top <= (MetaWord*)end(),
 123          "Chunk " PTR_FORMAT ": Chunk top out of chunk bounds.", p2i(this));
 124 
 125   // For non-humongous chunks, starting address shall be aligned
 126   // to its chunk size. Humongous chunks start address is
 127   // aligned to specialized chunk size.
 128   const size_t required_alignment =
 129     (chunk_type != HumongousIndex ? word_size() : get_size_for_nonhumongous_chunktype(SpecializedIndex, is_class())) * sizeof(MetaWord);
 130   assert(is_aligned((address)this, required_alignment),
 131          "Chunk " PTR_FORMAT ": (size " SIZE_FORMAT ") not aligned to " SIZE_FORMAT ".",
 132          p2i(this), word_size() * sizeof(MetaWord), required_alignment);
 133 }
 134 

























 135 #endif // ASSERT
 136 
 137 // Helper, returns a descriptive name for the given index.
 138 const char* chunk_size_name(ChunkIndex index) {
 139   switch (index) {
 140     case SpecializedIndex:
 141       return "specialized";
 142     case SmallIndex:
 143       return "small";
 144     case MediumIndex:
 145       return "medium";
 146     case HumongousIndex:
 147       return "humongous";
 148     default:
 149       return "Invalid index";
 150   }

 151 }
 152 
 153 #ifdef ASSERT
 154 void do_verify_chunk(Metachunk* chunk) {
 155   guarantee(chunk != NULL, "Sanity");
 156   // Verify chunk itself; then verify that it is consistent with the
 157   // occupany map of its containing node.
 158   chunk->verify();
 159   VirtualSpaceNode* const vsn = chunk->container();
 160   OccupancyMap* const ocmap = vsn->occupancy_map();
 161   ocmap->verify_for_chunk(chunk);
 162 }
 163 #endif
 164 
 165 void do_update_in_use_info_for_chunk(Metachunk* chunk, bool inuse) {
 166   chunk->set_is_tagged_free(!inuse);
 167   OccupancyMap* const ocmap = chunk->container()->occupancy_map();
 168   ocmap->set_region_in_use((MetaWord*)chunk, chunk->word_size(), inuse);
 169 }


 170 
 171 } // namespace metaspace
 172 


   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 
  26 #include "precompiled.hpp"
  27 
  28 #include "logging/log.hpp"
  29 #include "memory/metaspace/chunkLevel.hpp"
  30 #include "memory/metaspace/constants.hpp"
  31 #include "memory/metaspace/metachunk.hpp"
  32 #include "memory/metaspace/metaspaceCommon.hpp"
  33 #include "memory/metaspace/virtualSpaceNode.hpp"
  34 
  35 #include "utilities/align.hpp"
  36 #include "utilities/copy.hpp"
  37 #include "utilities/debug.hpp"
  38 
  39 namespace metaspace {
  40 
  41 // Make sure that the Klass alignment also agree.
  42 STATIC_ASSERT(Metachunk::allocation_alignment_bytes == (size_t)KlassAlignmentInBytes);
  43 
  44 void Metachunk::remove_from_list() {
  45   if (_prev != NULL) {
  46     _prev->set_next(_next);
  47   }
  48   if (_next != NULL) {
  49     _next->set_prev(_prev);
  50   }
  51   _prev = _next = NULL;























  52 }
  53 
  54 
  55 // Commit uncommitted section of the chunk.
  56 // Fails if we hit a commit limit.
  57 bool Metachunk::commit_up_to(size_t new_committed_words) {
  58 
  59   // We should hold the expand lock at this point.
  60   assert_lock_strong(MetaspaceExpand_lock);
  61 
  62   assert(new_committed_words <= word_size(), "Sanity.");
  63 
  64   // Note: we may commit more than the area of our own chunk and that is okay.
  65   MetaWord* const commit_top = align_down(base() + committed_words(), constants::commit_granule_words);
  66   MetaWord* const new_commit_top = align_up(base() + new_committed_words, constants::commit_granule_words);
  67 
  68   // Function should only be called if there is someting to commit.
  69   assert(new_commit_top > commit_top, "No need to commit.");
  70 
  71   log_debug(metaspace)("Chunk " PTR_FORMAT ": attempting to move commit line to "
  72                        SIZE_FORMAT " words.", p2i(this), new_committed_words);
  73 
  74   if (!_vsnode->ensure_range_is_committed(commit_top, new_commit_top - commit_top)) {
  75     return false;
  76   }
  77 
  78   // Remember how far we have committed.
  79   _committed_words = new_commit_top - base();
  80   if (_committed_words > word_size()) {
  81     _committed_words = word_size();
  82   }
  83 
  84   return true;
  85 
  86 }
  87 
  88 
  89 // Ensure that chunk is committed up to at least new_committed_words words.
  90 // Fails if we hit a commit limit.
  91 bool Metachunk::ensure_committed(size_t new_committed_words) {
  92 
  93   bool rc = true;
  94 
  95   if (new_committed_words > committed_words()) {
  96     MutexLocker cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag);
  97     rc = commit_up_to(new_committed_words);
  98   }
  99 
 100   return rc;
 101 
 102 }
 103 
 104 bool Metachunk::ensure_committed_locked(size_t new_committed_words) {
 105 
 106   // the .._locked() variant should be called if we own the lock already.
 107   assert_lock_strong(MetaspaceExpand_lock);
 108 
 109   bool rc = true;
 110 
 111   if (new_committed_words > committed_words()) {
 112     rc = commit_up_to(new_committed_words);
 113   }
 114 
 115   return rc;
 116 
 117 }
 118 
 119 // Allocate word_size words from this chunk.
 120 //
 121 // May cause memory to be committed. That may fail if we hit a commit limit. In that case,
 122 //  NULL is returned and p_did_hit_commit_limit will be set to true.
 123 // If the remainder portion of the chunk was too small to hold the allocation,
 124 //  NULL is returned and p_did_hit_commit_limit will be set to false.
 125 MetaWord* Metachunk::allocate(size_t word_size, bool* p_did_hit_commit_limit) {
 126 
 127   size_t request_word_size = align_up(word_size, allocation_alignment_words);
 128 
 129   log_trace(metaspace)("Chunk " PTR_FORMAT ": allocating "
 130                        SIZE_FORMAT " words.", p2i(this), word_size);
 131 
 132   // Space enough left?
 133   if (free_words() < request_word_size) {
 134     *p_did_hit_commit_limit = false;
 135     log_trace(metaspace)("Chunk " PTR_FORMAT ": .. does not fit (remaining space: "
 136                          SIZE_FORMAT " words).", p2i(this), free_words());
 137     return NULL;
 138   }
 139 
 140   // Expand committed region if necessary.
 141   if (ensure_committed(used_words() + request_word_size) == false) {
 142     *p_did_hit_commit_limit = true;
 143     log_trace(metaspace)("Chunk " PTR_FORMAT ": .. failed, we hit a limit.", p2i(this));
 144     return NULL;
 145   }
 146 
 147   MetaWord* const p = top();
 148 
 149   _used_words += request_word_size;
 150 
 151   return p;
 152 
 153 }
 154 
 155 #ifdef ASSERT






























 156 
 157 void Metachunk::verify(bool slow) const {
 158 
 159   // Note: only call this on a life Metachunk.
 160   chklvl::check_valid_level(level());
 161 
 162   assert(base() != NULL, "No base ptr");
 163   assert(committed_words() >= used_words(), "Sanity");
 164   assert(word_size() >= committed_words(), "Sanity");
 165 
 166   // Test base pointer
 167   assert(vsnode() != NULL, "No space");
 168   vsnode()->check_pointer(base());
 169   assert(base() != NULL, "Base pointer NULL");
 170 
 171   // Starting address shall be aligned to chunk size.
 172   const size_t required_alignment = word_size() * sizeof(MetaWord);
 173   assert_is_aligned(base(), required_alignment);
 174 
 175   // Used words
 176   assert(used_words() < word_size(), "oob");
 177 
 178   // If we are not a root chunk, we shall have a reference to a tree node
 179   assert(tree_node_ref() != 0 || level() == chklvl::ROOT_CHUNK_LEVEL, "No parent node.");
 180 
 181 }
 182 #endif // ASSERT
 183 
 184 
 185 #ifdef ASSERT
 186 
 187 bool MetachunkList::contains(const Metachunk* c) const {
 188   for (Metachunk* c2 = first(); c2 != NULL; c2 = c2->next()) {
 189     if (c == c2) {
 190       return true;
 191     }





 192   }
 193   return false;
 194 }
 195 
 196 void MetachunkList::verify(bool slow) const {
 197   int num = 0;
 198   for (Metachunk* c = first(); c != NULL; c = c->next()) {
 199     num ++;
 200     if (slow) {
 201       c->verify(false);
 202     }
 203     _num.check(num);
 204   }







 205 }
 206 
 207 #endif // ASSERT
 208 
 209 } // namespace metaspace
 210 
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