jdk8-mips64-public/hotspot: src/share/vm/memory/freeList.cpp@8c95980d0b66 (annotated)

src/share/vm/memory/freeList.cpp@8c95980d0b66 (annotated)

src/share/vm/memory/freeList.cpp

Sat, 07 Nov 2020 10:30:02 +0800

author: aoqi
date: Sat, 07 Nov 2020 10:30:02 +0800
changeset 10026: 8c95980d0b66
parent 7535: 7ae4e26cb1e0
permissions: -rw-r--r--

Added tag mips-jdk8u275-b01 for changeset d3b4d62f391f

 /*
  * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #include "precompiled.hpp"
 #include "memory/freeBlockDictionary.hpp"
 #include "memory/freeList.hpp"
 #include "memory/metachunk.hpp"
 #include "memory/sharedHeap.hpp"
 #include "runtime/globals.hpp"
 #include "runtime/mutex.hpp"
 #include "runtime/vmThread.hpp"
 #include "utilities/macros.hpp"
 #if INCLUDE_ALL_GCS
 #include "gc_implementation/concurrentMarkSweep/freeChunk.hpp"
 #endif // INCLUDE_ALL_GCS
 // Free list.  A FreeList is used to access a linked list of chunks
 // of space in the heap.  The head and tail are maintained so that
 // items can be (as in the current implementation) added at the
 // at the tail of the list and removed from the head of the list to
 // maintain a FIFO queue.
 template <class Chunk>
 FreeList<Chunk>::FreeList() :
   _head(NULL), _tail(NULL)
 #ifdef ASSERT
   , _protecting_lock(NULL)
 #endif
 {
   _size         = 0;
   _count        = 0;
 }
 template <class Chunk>
 void FreeList<Chunk>::link_head(Chunk* v) {
   assert_proper_lock_protection();
   set_head(v);
   // If this method is not used (just set the head instead),
   // this check can be avoided.
   if (v != NULL) {
     v->link_prev(NULL);
   }
 }
 template <class Chunk>
 void FreeList<Chunk>::reset() {
   // Don't set the _size to 0 because this method is
   // used with a existing list that has a size but which has
   // been emptied.
   // Don't clear the _protecting_lock of an existing list.
   set_count(0);
   set_head(NULL);
   set_tail(NULL);
 }
 template <class Chunk>
 void FreeList<Chunk>::initialize() {
 #ifdef ASSERT
   // Needed early because it might be checked in other initializing code.
   set_protecting_lock(NULL);
 #endif
   reset();
   set_size(0);
 }
 template <class Chunk_t>
 Chunk_t* FreeList<Chunk_t>::get_chunk_at_head() {
   assert_proper_lock_protection();
   assert(head() == NULL || head()->prev() == NULL, "list invariant");
   assert(tail() == NULL || tail()->next() == NULL, "list invariant");
   Chunk_t* fc = head();
   if (fc != NULL) {
     Chunk_t* nextFC = fc->next();
     if (nextFC != NULL) {
       // The chunk fc being removed has a "next".  Set the "next" to the
       // "prev" of fc.
       nextFC->link_prev(NULL);
     } else { // removed tail of list
       link_tail(NULL);
     }
     link_head(nextFC);
     decrement_count();
   }
   assert(head() == NULL || head()->prev() == NULL, "list invariant");
   assert(tail() == NULL || tail()->next() == NULL, "list invariant");
   return fc;
 }
 template <class Chunk>
 void FreeList<Chunk>::getFirstNChunksFromList(size_t n, FreeList<Chunk>* fl) {
   assert_proper_lock_protection();
   assert(fl->count() == 0, "Precondition");
   if (count() > 0) {
     int k = 1;
     fl->set_head(head()); n--;
     Chunk* tl = head();
     while (tl->next() != NULL && n > 0) {
       tl = tl->next(); n--; k++;
     }
     assert(tl != NULL, "Loop Inv.");
     // First, fix up the list we took from.
     Chunk* new_head = tl->next();
     set_head(new_head);
     set_count(count() - k);
     if (new_head == NULL) {
       set_tail(NULL);
     } else {
       new_head->link_prev(NULL);
     }
     // Now we can fix up the tail.
     tl->link_next(NULL);
     // And return the result.
     fl->set_tail(tl);
     fl->set_count(k);
   }
 }
 // Remove this chunk from the list
 template <class Chunk>
 void FreeList<Chunk>::remove_chunk(Chunk*fc) {
    assert_proper_lock_protection();
    assert(head() != NULL, "Remove from empty list");
    assert(fc != NULL, "Remove a NULL chunk");
    assert(size() == fc->size(), "Wrong list");
    assert(head() == NULL || head()->prev() == NULL, "list invariant");
    assert(tail() == NULL || tail()->next() == NULL, "list invariant");
    Chunk* prevFC = fc->prev();
    Chunk* nextFC = fc->next();
    if (nextFC != NULL) {
      // The chunk fc being removed has a "next".  Set the "next" to the
      // "prev" of fc.
      nextFC->link_prev(prevFC);
    } else { // removed tail of list
      link_tail(prevFC);
    }
    if (prevFC == NULL) { // removed head of list
      link_head(nextFC);
      assert(nextFC == NULL || nextFC->prev() == NULL,
        "Prev of head should be NULL");
    } else {
      prevFC->link_next(nextFC);
      assert(tail() != prevFC || prevFC->next() == NULL,
        "Next of tail should be NULL");
    }
    decrement_count();
    assert(((head() == NULL) + (tail() == NULL) + (count() == 0)) % 3 == 0,
           "H/T/C Inconsistency");
    // clear next and prev fields of fc, debug only
    NOT_PRODUCT(
      fc->link_prev(NULL);
      fc->link_next(NULL);
    )
    assert(fc->is_free(), "Should still be a free chunk");
    assert(head() == NULL || head()->prev() == NULL, "list invariant");
    assert(tail() == NULL || tail()->next() == NULL, "list invariant");
    assert(head() == NULL || head()->size() == size(), "wrong item on list");
    assert(tail() == NULL || tail()->size() == size(), "wrong item on list");
 }
 // Add this chunk at the head of the list.
 template <class Chunk>
 void FreeList<Chunk>::return_chunk_at_head(Chunk* chunk, bool record_return) {
   assert_proper_lock_protection();
   assert(chunk != NULL, "insert a NULL chunk");
   assert(size() == chunk->size(), "Wrong size");
   assert(head() == NULL || head()->prev() == NULL, "list invariant");
   assert(tail() == NULL || tail()->next() == NULL, "list invariant");
   Chunk* oldHead = head();
   assert(chunk != oldHead, "double insertion");
   chunk->link_after(oldHead);
   link_head(chunk);
   if (oldHead == NULL) { // only chunk in list
     assert(tail() == NULL, "inconsistent FreeList");
     link_tail(chunk);
   }
   increment_count(); // of # of chunks in list
   assert(head() == NULL || head()->prev() == NULL, "list invariant");
   assert(tail() == NULL || tail()->next() == NULL, "list invariant");
   assert(head() == NULL || head()->size() == size(), "wrong item on list");
   assert(tail() == NULL || tail()->size() == size(), "wrong item on list");
 }
 template <class Chunk>
 void FreeList<Chunk>::return_chunk_at_head(Chunk* chunk) {
   assert_proper_lock_protection();
   return_chunk_at_head(chunk, true);
 }
 // Add this chunk at the tail of the list.
 template <class Chunk>
 void FreeList<Chunk>::return_chunk_at_tail(Chunk* chunk, bool record_return) {
   assert_proper_lock_protection();
   assert(head() == NULL || head()->prev() == NULL, "list invariant");
   assert(tail() == NULL || tail()->next() == NULL, "list invariant");
   assert(chunk != NULL, "insert a NULL chunk");
   assert(size() == chunk->size(), "wrong size");
   Chunk* oldTail = tail();
   assert(chunk != oldTail, "double insertion");
   if (oldTail != NULL) {
     oldTail->link_after(chunk);
   } else { // only chunk in list
     assert(head() == NULL, "inconsistent FreeList");
     link_head(chunk);
   }
   link_tail(chunk);
   increment_count();  // of # of chunks in list
   assert(head() == NULL || head()->prev() == NULL, "list invariant");
   assert(tail() == NULL || tail()->next() == NULL, "list invariant");
   assert(head() == NULL || head()->size() == size(), "wrong item on list");
   assert(tail() == NULL || tail()->size() == size(), "wrong item on list");
 }
 template <class Chunk>
 void FreeList<Chunk>::return_chunk_at_tail(Chunk* chunk) {
   return_chunk_at_tail(chunk, true);
 }
 template <class Chunk>
 void FreeList<Chunk>::prepend(FreeList<Chunk>* fl) {
   assert_proper_lock_protection();
   if (fl->count() > 0) {
     if (count() == 0) {
       set_head(fl->head());
       set_tail(fl->tail());
       set_count(fl->count());
     } else {
       // Both are non-empty.
       Chunk* fl_tail = fl->tail();
       Chunk* this_head = head();
       assert(fl_tail->next() == NULL, "Well-formedness of fl");
       fl_tail->link_next(this_head);
       this_head->link_prev(fl_tail);
       set_head(fl->head());
       set_count(count() + fl->count());
     }
     fl->set_head(NULL);
     fl->set_tail(NULL);
     fl->set_count(0);
   }
 }
 // verify_chunk_in_free_lists() is used to verify that an item is in this free list.
 // It is used as a debugging aid.
 template <class Chunk>
 bool FreeList<Chunk>::verify_chunk_in_free_list(Chunk* fc) const {
   // This is an internal consistency check, not part of the check that the
   // chunk is in the free lists.
   guarantee(fc->size() == size(), "Wrong list is being searched");
   Chunk* curFC = head();
   while (curFC) {
     // This is an internal consistency check.
     guarantee(size() == curFC->size(), "Chunk is in wrong list.");
     if (fc == curFC) {
       return true;
     }
     curFC = curFC->next();
   }
   return false;
 }
 #ifndef PRODUCT
 template <class Chunk>
 void FreeList<Chunk>::assert_proper_lock_protection_work() const {
   assert(protecting_lock() != NULL, "Don't call this directly");
   assert(ParallelGCThreads > 0, "Don't call this directly");
   Thread* thr = Thread::current();
   if (thr->is_VM_thread() || thr->is_ConcurrentGC_thread()) {
     // assert that we are holding the freelist lock
   } else if (thr->is_GC_task_thread()) {
     assert(protecting_lock()->owned_by_self(), "FreeList RACE DETECTED");
   } else if (thr->is_Java_thread()) {
     assert(!SafepointSynchronize::is_at_safepoint(), "Should not be executing");
   } else {
     ShouldNotReachHere();  // unaccounted thread type?
   }
 }
 #endif
 // Print the "label line" for free list stats.
 template <class Chunk>
 void FreeList<Chunk>::print_labels_on(outputStream* st, const char* c) {
   st->print("%16s\t", c);
   st->print("%14s\t"    "%14s\t"    "%14s\t"    "%14s\t"    "%14s\t"
             "%14s\t"    "%14s\t"    "%14s\t"    "%14s\t"    "%14s\t"    "\n",
             "bfrsurp", "surplus", "desired", "prvSwep", "bfrSwep",
             "count",   "cBirths", "cDeaths", "sBirths", "sDeaths");
 }
 // Print the AllocationStats for the given free list. If the second argument
 // to the call is a non-null string, it is printed in the first column;
 // otherwise, if the argument is null (the default), then the size of the
 // (free list) block is printed in the first column.
 template <class Chunk_t>
 void FreeList<Chunk_t>::print_on(outputStream* st, const char* c) const {
   if (c != NULL) {
     st->print("%16s", c);
   } else {
     st->print(SIZE_FORMAT_W(16), size());
   }
 }
 template class FreeList<Metablock>;
 template class FreeList<Metachunk>;
 #if INCLUDE_ALL_GCS
 template class FreeList<FreeChunk>;
 #endif // INCLUDE_ALL_GCS

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/memory/freeList.cpp@8c95980d0b66 (annotated)

src/share/vm/memory/freeList.cpp