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 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_HPP
27
28 #include "gc_implementation/g1/concurrentMark.hpp"
29 #include "gc_implementation/g1/evacuationInfo.hpp"
30 #include "gc_implementation/g1/g1AllocRegion.hpp"
31 #include "gc_implementation/g1/g1BiasedArray.hpp"
32 #include "gc_implementation/g1/g1HRPrinter.hpp"
33 #include "gc_implementation/g1/g1MonitoringSupport.hpp"
34 #include "gc_implementation/g1/g1RemSet.hpp"
35 #include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
36 #include "gc_implementation/g1/g1YCTypes.hpp"
37 #include "gc_implementation/g1/heapRegionSeq.hpp"
38 #include "gc_implementation/g1/heapRegionSet.hpp"
39 #include "gc_implementation/shared/hSpaceCounters.hpp"
40 #include "gc_implementation/shared/parGCAllocBuffer.hpp"
41 #include "memory/barrierSet.hpp"
42 #include "memory/memRegion.hpp"
43 #include "memory/sharedHeap.hpp"
44 #include "utilities/stack.hpp"
45
46 // A "G1CollectedHeap" is an implementation of a java heap for HotSpot.
47 // It uses the "Garbage First" heap organization and algorithm, which
48 // may combine concurrent marking with parallel, incremental compaction of
49 // heap subsets that will yield large amounts of garbage.
50
51 // Forward declarations
52 class HeapRegion;
53 class HRRSCleanupTask;
54 class GenerationSpec;
1692 public:
1693 G1ParGCAllocBuffer(size_t gclab_word_size);
1694 virtual ~G1ParGCAllocBuffer() {
1695 guarantee(_retired, "Allocation buffer has not been retired");
1696 }
1697
1698 virtual void set_buf(HeapWord* buf) {
1699 ParGCAllocBuffer::set_buf(buf);
1700 _retired = false;
1701 }
1702
1703 virtual void retire(bool end_of_gc, bool retain) {
1704 if (_retired) {
1705 return;
1706 }
1707 ParGCAllocBuffer::retire(end_of_gc, retain);
1708 _retired = true;
1709 }
1710 };
1711
1712 class G1ParScanThreadState : public StackObj {
1713 protected:
1714 G1CollectedHeap* _g1h;
1715 RefToScanQueue* _refs;
1716 DirtyCardQueue _dcq;
1717 G1SATBCardTableModRefBS* _ct_bs;
1718 G1RemSet* _g1_rem;
1719
1720 G1ParGCAllocBuffer _surviving_alloc_buffer;
1721 G1ParGCAllocBuffer _tenured_alloc_buffer;
1722 G1ParGCAllocBuffer* _alloc_buffers[GCAllocPurposeCount];
1723 ageTable _age_table;
1724
1725 G1ParScanClosure _scanner;
1726
1727 size_t _alloc_buffer_waste;
1728 size_t _undo_waste;
1729
1730 OopsInHeapRegionClosure* _evac_failure_cl;
1731
1732 int _hash_seed;
1733 uint _queue_num;
1734
1735 size_t _term_attempts;
1736
1737 double _start;
1738 double _start_strong_roots;
1739 double _strong_roots_time;
1740 double _start_term;
1741 double _term_time;
1742
1743 // Map from young-age-index (0 == not young, 1 is youngest) to
1744 // surviving words. base is what we get back from the malloc call
1745 size_t* _surviving_young_words_base;
1746 // this points into the array, as we use the first few entries for padding
1747 size_t* _surviving_young_words;
1748
1749 #define PADDING_ELEM_NUM (DEFAULT_CACHE_LINE_SIZE / sizeof(size_t))
1750
1751 void add_to_alloc_buffer_waste(size_t waste) { _alloc_buffer_waste += waste; }
1752
1753 void add_to_undo_waste(size_t waste) { _undo_waste += waste; }
1754
1755 DirtyCardQueue& dirty_card_queue() { return _dcq; }
1756 G1SATBCardTableModRefBS* ctbs() { return _ct_bs; }
1757
1758 template <class T> inline void immediate_rs_update(HeapRegion* from, T* p, int tid);
1759
1760 template <class T> void deferred_rs_update(HeapRegion* from, T* p, int tid) {
1761 // If the new value of the field points to the same region or
1762 // is the to-space, we don't need to include it in the Rset updates.
1763 if (!from->is_in_reserved(oopDesc::load_decode_heap_oop(p)) && !from->is_survivor()) {
1764 size_t card_index = ctbs()->index_for(p);
1765 // If the card hasn't been added to the buffer, do it.
1766 if (ctbs()->mark_card_deferred(card_index)) {
1767 dirty_card_queue().enqueue((jbyte*)ctbs()->byte_for_index(card_index));
1768 }
1769 }
1770 }
1771
1772 public:
1773 G1ParScanThreadState(G1CollectedHeap* g1h, uint queue_num, ReferenceProcessor* rp);
1774
1775 ~G1ParScanThreadState() {
1776 retire_alloc_buffers();
1777 FREE_C_HEAP_ARRAY(size_t, _surviving_young_words_base, mtGC);
1778 }
1779
1780 RefToScanQueue* refs() { return _refs; }
1781 ageTable* age_table() { return &_age_table; }
1782
1783 G1ParGCAllocBuffer* alloc_buffer(GCAllocPurpose purpose) {
1784 return _alloc_buffers[purpose];
1785 }
1786
1787 size_t alloc_buffer_waste() const { return _alloc_buffer_waste; }
1788 size_t undo_waste() const { return _undo_waste; }
1789
1790 #ifdef ASSERT
1791 bool verify_ref(narrowOop* ref) const;
1792 bool verify_ref(oop* ref) const;
1793 bool verify_task(StarTask ref) const;
1794 #endif // ASSERT
1795
1796 template <class T> void push_on_queue(T* ref) {
1797 assert(verify_ref(ref), "sanity");
1798 refs()->push(ref);
1799 }
1800
1801 template <class T> inline void update_rs(HeapRegion* from, T* p, int tid);
1802
1803 HeapWord* allocate_slow(GCAllocPurpose purpose, size_t word_sz) {
1804 HeapWord* obj = NULL;
1805 size_t gclab_word_size = _g1h->desired_plab_sz(purpose);
1806 if (word_sz * 100 < gclab_word_size * ParallelGCBufferWastePct) {
1807 G1ParGCAllocBuffer* alloc_buf = alloc_buffer(purpose);
1808 add_to_alloc_buffer_waste(alloc_buf->words_remaining());
1809 alloc_buf->retire(false /* end_of_gc */, false /* retain */);
1810
1811 HeapWord* buf = _g1h->par_allocate_during_gc(purpose, gclab_word_size);
1812 if (buf == NULL) return NULL; // Let caller handle allocation failure.
1813 // Otherwise.
1814 alloc_buf->set_word_size(gclab_word_size);
1815 alloc_buf->set_buf(buf);
1816
1817 obj = alloc_buf->allocate(word_sz);
1818 assert(obj != NULL, "buffer was definitely big enough...");
1819 } else {
1820 obj = _g1h->par_allocate_during_gc(purpose, word_sz);
1821 }
1822 return obj;
1823 }
1824
1825 HeapWord* allocate(GCAllocPurpose purpose, size_t word_sz) {
1826 HeapWord* obj = alloc_buffer(purpose)->allocate(word_sz);
1827 if (obj != NULL) return obj;
1828 return allocate_slow(purpose, word_sz);
1829 }
1830
1831 void undo_allocation(GCAllocPurpose purpose, HeapWord* obj, size_t word_sz) {
1832 if (alloc_buffer(purpose)->contains(obj)) {
1833 assert(alloc_buffer(purpose)->contains(obj + word_sz - 1),
1834 "should contain whole object");
1835 alloc_buffer(purpose)->undo_allocation(obj, word_sz);
1836 } else {
1837 CollectedHeap::fill_with_object(obj, word_sz);
1838 add_to_undo_waste(word_sz);
1839 }
1840 }
1841
1842 void set_evac_failure_closure(OopsInHeapRegionClosure* evac_failure_cl) {
1843 _evac_failure_cl = evac_failure_cl;
1844 }
1845 OopsInHeapRegionClosure* evac_failure_closure() {
1846 return _evac_failure_cl;
1847 }
1848
1849 int* hash_seed() { return &_hash_seed; }
1850 uint queue_num() { return _queue_num; }
1851
1852 size_t term_attempts() const { return _term_attempts; }
1853 void note_term_attempt() { _term_attempts++; }
1854
1855 void start_strong_roots() {
1856 _start_strong_roots = os::elapsedTime();
1857 }
1858 void end_strong_roots() {
1859 _strong_roots_time += (os::elapsedTime() - _start_strong_roots);
1860 }
1861 double strong_roots_time() const { return _strong_roots_time; }
1862
1863 void start_term_time() {
1864 note_term_attempt();
1865 _start_term = os::elapsedTime();
1866 }
1867 void end_term_time() {
1868 _term_time += (os::elapsedTime() - _start_term);
1869 }
1870 double term_time() const { return _term_time; }
1871
1872 double elapsed_time() const {
1873 return os::elapsedTime() - _start;
1874 }
1875
1876 static void
1877 print_termination_stats_hdr(outputStream* const st = gclog_or_tty);
1878 void
1879 print_termination_stats(int i, outputStream* const st = gclog_or_tty) const;
1880
1881 size_t* surviving_young_words() {
1882 // We add on to hide entry 0 which accumulates surviving words for
1883 // age -1 regions (i.e. non-young ones)
1884 return _surviving_young_words;
1885 }
1886
1887 private:
1888 void retire_alloc_buffers() {
1889 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) {
1890 size_t waste = _alloc_buffers[ap]->words_remaining();
1891 add_to_alloc_buffer_waste(waste);
1892 _alloc_buffers[ap]->flush_stats_and_retire(_g1h->stats_for_purpose((GCAllocPurpose)ap),
1893 true /* end_of_gc */,
1894 false /* retain */);
1895 }
1896 }
1897
1898 #define G1_PARTIAL_ARRAY_MASK 0x2
1899
1900 inline bool has_partial_array_mask(oop* ref) const {
1901 return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK;
1902 }
1903
1904 // We never encode partial array oops as narrowOop*, so return false immediately.
1905 // This allows the compiler to create optimized code when popping references from
1906 // the work queue.
1907 inline bool has_partial_array_mask(narrowOop* ref) const {
1908 assert(((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) != G1_PARTIAL_ARRAY_MASK, "Partial array oop reference encoded as narrowOop*");
1909 return false;
1910 }
1911
1912 // Only implement set_partial_array_mask() for regular oops, not for narrowOops.
1913 // We always encode partial arrays as regular oop, to allow the
1914 // specialization for has_partial_array_mask() for narrowOops above.
1915 // This means that unintentional use of this method with narrowOops are caught
1916 // by the compiler.
1917 inline oop* set_partial_array_mask(oop obj) const {
1918 assert(((uintptr_t)(void *)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!");
1919 return (oop*) ((uintptr_t)(void *)obj | G1_PARTIAL_ARRAY_MASK);
1920 }
1921
1922 inline oop clear_partial_array_mask(oop* ref) const {
1923 return cast_to_oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
1924 }
1925
1926 inline void do_oop_partial_array(oop* p);
1927
1928 // This method is applied to the fields of the objects that have just been copied.
1929 template <class T> void do_oop_evac(T* p, HeapRegion* from) {
1930 assert(!oopDesc::is_null(oopDesc::load_decode_heap_oop(p)),
1931 "Reference should not be NULL here as such are never pushed to the task queue.");
1932 oop obj = oopDesc::load_decode_heap_oop_not_null(p);
1933
1934 // Although we never intentionally push references outside of the collection
1935 // set, due to (benign) races in the claim mechanism during RSet scanning more
1936 // than one thread might claim the same card. So the same card may be
1937 // processed multiple times. So redo this check.
1938 if (_g1h->in_cset_fast_test(obj)) {
1939 oop forwardee;
1940 if (obj->is_forwarded()) {
1941 forwardee = obj->forwardee();
1942 } else {
1943 forwardee = copy_to_survivor_space(obj);
1944 }
1945 assert(forwardee != NULL, "forwardee should not be NULL");
1946 oopDesc::encode_store_heap_oop(p, forwardee);
1947 }
1948
1949 assert(obj != NULL, "Must be");
1950 update_rs(from, p, queue_num());
1951 }
1952 public:
1953
1954 oop copy_to_survivor_space(oop const obj);
1955
1956 template <class T> inline void deal_with_reference(T* ref_to_scan);
1957
1958 inline void deal_with_reference(StarTask ref);
1959
1960 public:
1961 void trim_queue();
1962 };
1963
1964 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_HPP
|
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 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_HPP
27
28 #include "gc_implementation/g1/concurrentMark.hpp"
29 #include "gc_implementation/g1/evacuationInfo.hpp"
30 #include "gc_implementation/g1/g1AllocRegion.hpp"
31 #include "gc_implementation/g1/g1BiasedArray.hpp"
32 #include "gc_implementation/g1/g1HRPrinter.hpp"
33 #include "gc_implementation/g1/g1MonitoringSupport.hpp"
34 #include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
35 #include "gc_implementation/g1/g1YCTypes.hpp"
36 #include "gc_implementation/g1/heapRegionSeq.hpp"
37 #include "gc_implementation/g1/heapRegionSet.hpp"
38 #include "gc_implementation/shared/hSpaceCounters.hpp"
39 #include "gc_implementation/shared/parGCAllocBuffer.hpp"
40 #include "memory/barrierSet.hpp"
41 #include "memory/memRegion.hpp"
42 #include "memory/sharedHeap.hpp"
43 #include "utilities/stack.hpp"
44
45 // A "G1CollectedHeap" is an implementation of a java heap for HotSpot.
46 // It uses the "Garbage First" heap organization and algorithm, which
47 // may combine concurrent marking with parallel, incremental compaction of
48 // heap subsets that will yield large amounts of garbage.
49
50 // Forward declarations
51 class HeapRegion;
52 class HRRSCleanupTask;
53 class GenerationSpec;
1691 public:
1692 G1ParGCAllocBuffer(size_t gclab_word_size);
1693 virtual ~G1ParGCAllocBuffer() {
1694 guarantee(_retired, "Allocation buffer has not been retired");
1695 }
1696
1697 virtual void set_buf(HeapWord* buf) {
1698 ParGCAllocBuffer::set_buf(buf);
1699 _retired = false;
1700 }
1701
1702 virtual void retire(bool end_of_gc, bool retain) {
1703 if (_retired) {
1704 return;
1705 }
1706 ParGCAllocBuffer::retire(end_of_gc, retain);
1707 _retired = true;
1708 }
1709 };
1710
1711 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_HPP
|