src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp

Thu, 28 Mar 2013 10:27:28 +0100

author
mgerdin
date
Thu, 28 Mar 2013 10:27:28 +0100
changeset 4853
2e093b564241
parent 4016
c9814fadeb38
child 5811
d55c004e1d4d
permissions
-rw-r--r--

7014552: gc/lock/jni/jnilockXXX works too slow on 1-processor machine
Summary: Keep a counter of how many times we were stalled by the GC locker, add a diagnostic flag which sets the limit.
Reviewed-by: brutisso, ehelin, johnc

     1 /*
     2  * Copyright (c) 2001, 2012, 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.
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     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
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    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
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    23  */
    25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP
    26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP
    28 #include "gc_implementation/g1/concurrentMark.hpp"
    29 #include "gc_implementation/g1/g1CollectedHeap.hpp"
    30 #include "gc_implementation/g1/g1AllocRegion.inline.hpp"
    31 #include "gc_implementation/g1/g1CollectorPolicy.hpp"
    32 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
    33 #include "utilities/taskqueue.hpp"
    35 // Inline functions for G1CollectedHeap
    37 template <class T>
    38 inline HeapRegion*
    39 G1CollectedHeap::heap_region_containing(const T addr) const {
    40   HeapRegion* hr = _hrs.addr_to_region((HeapWord*) addr);
    41   // hr can be null if addr in perm_gen
    42   if (hr != NULL && hr->continuesHumongous()) {
    43     hr = hr->humongous_start_region();
    44   }
    45   return hr;
    46 }
    48 template <class T>
    49 inline HeapRegion*
    50 G1CollectedHeap::heap_region_containing_raw(const T addr) const {
    51   assert(_g1_reserved.contains((const void*) addr), "invariant");
    52   HeapRegion* res = _hrs.addr_to_region_unsafe((HeapWord*) addr);
    53   return res;
    54 }
    56 inline bool G1CollectedHeap::obj_in_cs(oop obj) {
    57   HeapRegion* r = _hrs.addr_to_region((HeapWord*) obj);
    58   return r != NULL && r->in_collection_set();
    59 }
    61 inline HeapWord*
    62 G1CollectedHeap::attempt_allocation(size_t word_size,
    63                                     unsigned int* gc_count_before_ret,
    64                                     int* gclocker_retry_count_ret) {
    65   assert_heap_not_locked_and_not_at_safepoint();
    66   assert(!isHumongous(word_size), "attempt_allocation() should not "
    67          "be called for humongous allocation requests");
    69   HeapWord* result = _mutator_alloc_region.attempt_allocation(word_size,
    70                                                       false /* bot_updates */);
    71   if (result == NULL) {
    72     result = attempt_allocation_slow(word_size,
    73                                      gc_count_before_ret,
    74                                      gclocker_retry_count_ret);
    75   }
    76   assert_heap_not_locked();
    77   if (result != NULL) {
    78     dirty_young_block(result, word_size);
    79   }
    80   return result;
    81 }
    83 inline HeapWord* G1CollectedHeap::survivor_attempt_allocation(size_t
    84                                                               word_size) {
    85   assert(!isHumongous(word_size),
    86          "we should not be seeing humongous-size allocations in this path");
    88   HeapWord* result = _survivor_gc_alloc_region.attempt_allocation(word_size,
    89                                                       false /* bot_updates */);
    90   if (result == NULL) {
    91     MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag);
    92     result = _survivor_gc_alloc_region.attempt_allocation_locked(word_size,
    93                                                       false /* bot_updates */);
    94   }
    95   if (result != NULL) {
    96     dirty_young_block(result, word_size);
    97   }
    98   return result;
    99 }
   101 inline HeapWord* G1CollectedHeap::old_attempt_allocation(size_t word_size) {
   102   assert(!isHumongous(word_size),
   103          "we should not be seeing humongous-size allocations in this path");
   105   HeapWord* result = _old_gc_alloc_region.attempt_allocation(word_size,
   106                                                        true /* bot_updates */);
   107   if (result == NULL) {
   108     MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag);
   109     result = _old_gc_alloc_region.attempt_allocation_locked(word_size,
   110                                                        true /* bot_updates */);
   111   }
   112   return result;
   113 }
   115 // It dirties the cards that cover the block so that so that the post
   116 // write barrier never queues anything when updating objects on this
   117 // block. It is assumed (and in fact we assert) that the block
   118 // belongs to a young region.
   119 inline void
   120 G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) {
   121   assert_heap_not_locked();
   123   // Assign the containing region to containing_hr so that we don't
   124   // have to keep calling heap_region_containing_raw() in the
   125   // asserts below.
   126   DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing_raw(start);)
   127   assert(containing_hr != NULL && start != NULL && word_size > 0,
   128          "pre-condition");
   129   assert(containing_hr->is_in(start), "it should contain start");
   130   assert(containing_hr->is_young(), "it should be young");
   131   assert(!containing_hr->isHumongous(), "it should not be humongous");
   133   HeapWord* end = start + word_size;
   134   assert(containing_hr->is_in(end - 1), "it should also contain end - 1");
   136   MemRegion mr(start, end);
   137   ((CardTableModRefBS*)_g1h->barrier_set())->dirty(mr);
   138 }
   140 inline RefToScanQueue* G1CollectedHeap::task_queue(int i) const {
   141   return _task_queues->queue(i);
   142 }
   144 inline bool G1CollectedHeap::isMarkedPrev(oop obj) const {
   145   return _cm->prevMarkBitMap()->isMarked((HeapWord *)obj);
   146 }
   148 inline bool G1CollectedHeap::isMarkedNext(oop obj) const {
   149   return _cm->nextMarkBitMap()->isMarked((HeapWord *)obj);
   150 }
   152 #ifndef PRODUCT
   153 // Support for G1EvacuationFailureALot
   155 inline bool
   156 G1CollectedHeap::evacuation_failure_alot_for_gc_type(bool gcs_are_young,
   157                                                      bool during_initial_mark,
   158                                                      bool during_marking) {
   159   bool res = false;
   160   if (during_marking) {
   161     res |= G1EvacuationFailureALotDuringConcMark;
   162   }
   163   if (during_initial_mark) {
   164     res |= G1EvacuationFailureALotDuringInitialMark;
   165   }
   166   if (gcs_are_young) {
   167     res |= G1EvacuationFailureALotDuringYoungGC;
   168   } else {
   169     // GCs are mixed
   170     res |= G1EvacuationFailureALotDuringMixedGC;
   171   }
   172   return res;
   173 }
   175 inline void
   176 G1CollectedHeap::set_evacuation_failure_alot_for_current_gc() {
   177   if (G1EvacuationFailureALot) {
   178     // Note we can't assert that _evacuation_failure_alot_for_current_gc
   179     // is clear here. It may have been set during a previous GC but that GC
   180     // did not copy enough objects (i.e. G1EvacuationFailureALotCount) to
   181     // trigger an evacuation failure and clear the flags and and counts.
   183     // Check if we have gone over the interval.
   184     const size_t gc_num = total_collections();
   185     const size_t elapsed_gcs = gc_num - _evacuation_failure_alot_gc_number;
   187     _evacuation_failure_alot_for_current_gc = (elapsed_gcs >= G1EvacuationFailureALotInterval);
   189     // Now check if G1EvacuationFailureALot is enabled for the current GC type.
   190     const bool gcs_are_young = g1_policy()->gcs_are_young();
   191     const bool during_im = g1_policy()->during_initial_mark_pause();
   192     const bool during_marking = mark_in_progress();
   194     _evacuation_failure_alot_for_current_gc &=
   195       evacuation_failure_alot_for_gc_type(gcs_are_young,
   196                                           during_im,
   197                                           during_marking);
   198   }
   199 }
   201 inline bool
   202 G1CollectedHeap::evacuation_should_fail() {
   203   if (!G1EvacuationFailureALot || !_evacuation_failure_alot_for_current_gc) {
   204     return false;
   205   }
   206   // G1EvacuationFailureALot is in effect for current GC
   207   // Access to _evacuation_failure_alot_count is not atomic;
   208   // the value does not have to be exact.
   209   if (++_evacuation_failure_alot_count < G1EvacuationFailureALotCount) {
   210     return false;
   211   }
   212   _evacuation_failure_alot_count = 0;
   213   return true;
   214 }
   216 inline void G1CollectedHeap::reset_evacuation_should_fail() {
   217   if (G1EvacuationFailureALot) {
   218     _evacuation_failure_alot_gc_number = total_collections();
   219     _evacuation_failure_alot_count = 0;
   220     _evacuation_failure_alot_for_current_gc = false;
   221   }
   222 }
   223 #endif  // #ifndef PRODUCT
   225 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP

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