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src/share/vm/memory/collectorPolicy.cpp

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rev 7780 : imported patch 8072621
   1 /*
   2  * Copyright (c) 2001, 2014, 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  *


 580 
 581   DEBUG_ONLY(GenCollectorPolicy::assert_size_info();)
 582 }
 583 
 584 HeapWord* GenCollectorPolicy::mem_allocate_work(size_t size,
 585                                         bool is_tlab,
 586                                         bool* gc_overhead_limit_was_exceeded) {
 587   GenCollectedHeap *gch = GenCollectedHeap::heap();
 588 
 589   debug_only(gch->check_for_valid_allocation_state());
 590   assert(gch->no_gc_in_progress(), "Allocation during gc not allowed");
 591 
 592   // In general gc_overhead_limit_was_exceeded should be false so
 593   // set it so here and reset it to true only if the gc time
 594   // limit is being exceeded as checked below.
 595   *gc_overhead_limit_was_exceeded = false;
 596 
 597   HeapWord* result = NULL;
 598 
 599   // Loop until the allocation is satisfied, or unsatisfied after GC.
 600   for (int try_count = 1, gclocker_stalled_count = 0; /* return or throw */; try_count += 1) {
 601     HandleMark hm; // Discard any handles allocated in each iteration.
 602 
 603     // First allocation attempt is lock-free.
 604     Generation *young = gch->get_gen(0);
 605     assert(young->supports_inline_contig_alloc(),
 606       "Otherwise, must do alloc within heap lock");
 607     if (young->should_allocate(size, is_tlab)) {
 608       result = young->par_allocate(size, is_tlab);
 609       if (result != NULL) {
 610         assert(gch->is_in_reserved(result), "result not in heap");
 611         return result;
 612       }
 613     }
 614     unsigned int gc_count_before;  // Read inside the Heap_lock locked region.
 615     {
 616       MutexLocker ml(Heap_lock);
 617       if (PrintGC && Verbose) {
 618         gclog_or_tty->print_cr("TwoGenerationCollectorPolicy::mem_allocate_work:"
 619                       " attempting locked slow path allocation");
 620       }
 621       // Note that only large objects get a shot at being
 622       // allocated in later generations.
 623       bool first_only = ! should_try_older_generation_allocation(size);
 624 
 625       result = gch->attempt_allocation(size, is_tlab, first_only);
 626       if (result != NULL) {
 627         assert(gch->is_in_reserved(result), "result not in heap");
 628         return result;
 629       }
 630 
 631       if (GC_locker::is_active_and_needs_gc()) {
 632         if (is_tlab) {
 633           return NULL;  // Caller will retry allocating individual object.
 634         }


   1 /*
   2  * Copyright (c) 2001, 2015, 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  *


 580 
 581   DEBUG_ONLY(GenCollectorPolicy::assert_size_info();)
 582 }
 583 
 584 HeapWord* GenCollectorPolicy::mem_allocate_work(size_t size,
 585                                         bool is_tlab,
 586                                         bool* gc_overhead_limit_was_exceeded) {
 587   GenCollectedHeap *gch = GenCollectedHeap::heap();
 588 
 589   debug_only(gch->check_for_valid_allocation_state());
 590   assert(gch->no_gc_in_progress(), "Allocation during gc not allowed");
 591 
 592   // In general gc_overhead_limit_was_exceeded should be false so
 593   // set it so here and reset it to true only if the gc time
 594   // limit is being exceeded as checked below.
 595   *gc_overhead_limit_was_exceeded = false;
 596 
 597   HeapWord* result = NULL;
 598 
 599   // Loop until the allocation is satisfied, or unsatisfied after GC.
 600   for (uint try_count = 1, gclocker_stalled_count = 0; /* return or throw */; try_count += 1) {
 601     HandleMark hm; // Discard any handles allocated in each iteration.
 602 
 603     // First allocation attempt is lock-free.
 604     Generation *young = gch->get_gen(0);
 605     assert(young->supports_inline_contig_alloc(),
 606       "Otherwise, must do alloc within heap lock");
 607     if (young->should_allocate(size, is_tlab)) {
 608       result = young->par_allocate(size, is_tlab);
 609       if (result != NULL) {
 610         assert(gch->is_in_reserved(result), "result not in heap");
 611         return result;
 612       }
 613     }
 614     uint gc_count_before;  // Read inside the Heap_lock locked region.
 615     {
 616       MutexLocker ml(Heap_lock);
 617       if (PrintGC && Verbose) {
 618         gclog_or_tty->print_cr("TwoGenerationCollectorPolicy::mem_allocate_work:"
 619                       " attempting locked slow path allocation");
 620       }
 621       // Note that only large objects get a shot at being
 622       // allocated in later generations.
 623       bool first_only = ! should_try_older_generation_allocation(size);
 624 
 625       result = gch->attempt_allocation(size, is_tlab, first_only);
 626       if (result != NULL) {
 627         assert(gch->is_in_reserved(result), "result not in heap");
 628         return result;
 629       }
 630 
 631       if (GC_locker::is_active_and_needs_gc()) {
 632         if (is_tlab) {
 633           return NULL;  // Caller will retry allocating individual object.
 634         }


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