--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/parallelScavengeHeap.hpp Fri May 31 10:04:00 2013 -0700
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/parallelScavengeHeap.hpp Sat Jun 01 10:00:56 2013 +0200
@@ -116,7 +116,7 @@
// The alignment used for eden and survivors within the young gen
// and for boundary between young gen and old gen.
- size_t intra_heap_alignment() const { return 64 * K; }
+ size_t intra_heap_alignment() const { return 64 * K * HeapWordSize; }
size_t capacity() const;
size_t used() const;
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp Fri May 31 10:04:00 2013 -0700
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp Sat Jun 01 10:00:56 2013 +0200
@@ -59,13 +59,25 @@
#include <math.h>
// All sizes are in HeapWords.
-const size_t ParallelCompactData::Log2RegionSize = 9; // 512 words
+const size_t ParallelCompactData::Log2RegionSize = 16; // 64K words
const size_t ParallelCompactData::RegionSize = (size_t)1 << Log2RegionSize;
const size_t ParallelCompactData::RegionSizeBytes =
RegionSize << LogHeapWordSize;
const size_t ParallelCompactData::RegionSizeOffsetMask = RegionSize - 1;
const size_t ParallelCompactData::RegionAddrOffsetMask = RegionSizeBytes - 1;
-const size_t ParallelCompactData::RegionAddrMask = ~RegionAddrOffsetMask;
+const size_t ParallelCompactData::RegionAddrMask = ~RegionAddrOffsetMask;
+
+const size_t ParallelCompactData::Log2BlockSize = 7; // 128 words
+const size_t ParallelCompactData::BlockSize = (size_t)1 << Log2BlockSize;
+const size_t ParallelCompactData::BlockSizeBytes =
+ BlockSize << LogHeapWordSize;
+const size_t ParallelCompactData::BlockSizeOffsetMask = BlockSize - 1;
+const size_t ParallelCompactData::BlockAddrOffsetMask = BlockSizeBytes - 1;
+const size_t ParallelCompactData::BlockAddrMask = ~BlockAddrOffsetMask;
+
+const size_t ParallelCompactData::BlocksPerRegion = RegionSize / BlockSize;
+const size_t ParallelCompactData::Log2BlocksPerRegion =
+ Log2RegionSize - Log2BlockSize;
const ParallelCompactData::RegionData::region_sz_t
ParallelCompactData::RegionData::dc_shift = 27;
@@ -359,6 +371,10 @@
_reserved_byte_size = 0;
_region_data = 0;
_region_count = 0;
+
+ _block_vspace = 0;
+ _block_data = 0;
+ _block_count = 0;
}
bool ParallelCompactData::initialize(MemRegion covered_region)
@@ -372,8 +388,7 @@
assert((region_size & RegionSizeOffsetMask) == 0,
"region size not a multiple of RegionSize");
- bool result = initialize_region_data(region_size);
-
+ bool result = initialize_region_data(region_size) && initialize_block_data();
return result;
}
@@ -418,17 +433,36 @@
return false;
}
+bool ParallelCompactData::initialize_block_data()
+{
+ assert(_region_count != 0, "region data must be initialized first");
+ const size_t count = _region_count << Log2BlocksPerRegion;
+ _block_vspace = create_vspace(count, sizeof(BlockData));
+ if (_block_vspace != 0) {
+ _block_data = (BlockData*)_block_vspace->reserved_low_addr();
+ _block_count = count;
+ return true;
+ }
+ return false;
+}
+
void ParallelCompactData::clear()
{
memset(_region_data, 0, _region_vspace->committed_size());
+ memset(_block_data, 0, _block_vspace->committed_size());
}
void ParallelCompactData::clear_range(size_t beg_region, size_t end_region) {
assert(beg_region <= _region_count, "beg_region out of range");
assert(end_region <= _region_count, "end_region out of range");
+ assert(RegionSize % BlockSize == 0, "RegionSize not a multiple of BlockSize");
const size_t region_cnt = end_region - beg_region;
memset(_region_data + beg_region, 0, region_cnt * sizeof(RegionData));
+
+ const size_t beg_block = beg_region * BlocksPerRegion;
+ const size_t block_cnt = region_cnt * BlocksPerRegion;
+ memset(_block_data + beg_block, 0, block_cnt * sizeof(BlockData));
}
HeapWord* ParallelCompactData::partial_obj_end(size_t region_idx) const
@@ -707,49 +741,48 @@
HeapWord* ParallelCompactData::calc_new_pointer(HeapWord* addr) {
assert(addr != NULL, "Should detect NULL oop earlier");
- assert(PSParallelCompact::gc_heap()->is_in(addr), "addr not in heap");
-#ifdef ASSERT
- if (PSParallelCompact::mark_bitmap()->is_unmarked(addr)) {
- gclog_or_tty->print_cr("calc_new_pointer:: addr " PTR_FORMAT, addr);
- }
-#endif
- assert(PSParallelCompact::mark_bitmap()->is_marked(addr), "obj not marked");
+ assert(PSParallelCompact::gc_heap()->is_in(addr), "not in heap");
+ assert(PSParallelCompact::mark_bitmap()->is_marked(addr), "not marked");
// Region covering the object.
- size_t region_index = addr_to_region_idx(addr);
- const RegionData* const region_ptr = region(region_index);
- HeapWord* const region_addr = region_align_down(addr);
-
- assert(addr < region_addr + RegionSize, "Region does not cover object");
- assert(addr_to_region_ptr(region_addr) == region_ptr, "sanity check");
-
+ RegionData* const region_ptr = addr_to_region_ptr(addr);
HeapWord* result = region_ptr->destination();
- // If all the data in the region is live, then the new location of the object
- // can be calculated from the destination of the region plus the offset of the
- // object in the region.
+ // If the entire Region is live, the new location is region->destination + the
+ // offset of the object within in the Region.
+
+ // Run some performance tests to determine if this special case pays off. It
+ // is worth it for pointers into the dense prefix. If the optimization to
+ // avoid pointer updates in regions that only point to the dense prefix is
+ // ever implemented, this should be revisited.
if (region_ptr->data_size() == RegionSize) {
- result += pointer_delta(addr, region_addr);
- DEBUG_ONLY(PSParallelCompact::check_new_location(addr, result);)
+ result += region_offset(addr);
return result;
}
- // The new location of the object is
- // region destination +
- // size of the partial object extending onto the region +
- // sizes of the live objects in the Region that are to the left of addr
- const size_t partial_obj_size = region_ptr->partial_obj_size();
- HeapWord* const search_start = region_addr + partial_obj_size;
+ // Otherwise, the new location is region->destination + block offset + the
+ // number of live words in the Block that are (a) to the left of addr and (b)
+ // due to objects that start in the Block.
+
+ // Fill in the block table if necessary. This is unsynchronized, so multiple
+ // threads may fill the block table for a region (harmless, since it is
+ // idempotent).
+ if (!region_ptr->blocks_filled()) {
+ PSParallelCompact::fill_blocks(addr_to_region_idx(addr));
+ region_ptr->set_blocks_filled();
+ }
+
+ HeapWord* const search_start = block_align_down(addr);
+ const size_t block_offset = addr_to_block_ptr(addr)->offset();
const ParMarkBitMap* bitmap = PSParallelCompact::mark_bitmap();
- size_t live_to_left = bitmap->live_words_in_range(search_start, oop(addr));
-
- result += partial_obj_size + live_to_left;
- DEBUG_ONLY(PSParallelCompact::check_new_location(addr, result);)
+ const size_t live = bitmap->live_words_in_range(search_start, oop(addr));
+ result += block_offset + live;
+ DEBUG_ONLY(PSParallelCompact::check_new_location(addr, result));
return result;
}
-#ifdef ASSERT
+#ifdef ASSERT
void ParallelCompactData::verify_clear(const PSVirtualSpace* vspace)
{
const size_t* const beg = (const size_t*)vspace->committed_low_addr();
@@ -762,16 +795,10 @@
void ParallelCompactData::verify_clear()
{
verify_clear(_region_vspace);
+ verify_clear(_block_vspace);
}
#endif // #ifdef ASSERT
-#ifdef NOT_PRODUCT
-ParallelCompactData::RegionData* debug_region(size_t region_index) {
- ParallelCompactData& sd = PSParallelCompact::summary_data();
- return sd.region(region_index);
-}
-#endif
-
elapsedTimer PSParallelCompact::_accumulated_time;
unsigned int PSParallelCompact::_total_invocations = 0;
unsigned int PSParallelCompact::_maximum_compaction_gc_num = 0;
@@ -1961,11 +1988,6 @@
maximum_heap_compaction);
}
-bool ParallelCompactData::region_contains(size_t region_index, HeapWord* addr) {
- size_t addr_region_index = addr_to_region_idx(addr);
- return region_index == addr_region_index;
-}
-
// This method contains no policy. You should probably
// be calling invoke() instead.
bool PSParallelCompact::invoke_no_policy(bool maximum_heap_compaction) {
@@ -2627,6 +2649,41 @@
}
}
+#ifdef ASSERT
+// Write a histogram of the number of times the block table was filled for a
+// region.
+void PSParallelCompact::write_block_fill_histogram(outputStream* const out)
+{
+ if (!TraceParallelOldGCCompactionPhase) return;
+
+ typedef ParallelCompactData::RegionData rd_t;
+ ParallelCompactData& sd = summary_data();
+
+ for (unsigned int id = old_space_id; id < last_space_id; ++id) {
+ MutableSpace* const spc = _space_info[id].space();
+ if (spc->bottom() != spc->top()) {
+ const rd_t* const beg = sd.addr_to_region_ptr(spc->bottom());
+ HeapWord* const top_aligned_up = sd.region_align_up(spc->top());
+ const rd_t* const end = sd.addr_to_region_ptr(top_aligned_up);
+
+ size_t histo[5] = { 0, 0, 0, 0, 0 };
+ const size_t histo_len = sizeof(histo) / sizeof(size_t);
+ const size_t region_cnt = pointer_delta(end, beg, sizeof(rd_t));
+
+ for (const rd_t* cur = beg; cur < end; ++cur) {
+ ++histo[MIN2(cur->blocks_filled_count(), histo_len - 1)];
+ }
+ out->print("%u %-4s" SIZE_FORMAT_W(5), id, space_names[id], region_cnt);
+ for (size_t i = 0; i < histo_len; ++i) {
+ out->print(" " SIZE_FORMAT_W(5) " %5.1f%%",
+ histo[i], 100.0 * histo[i] / region_cnt);
+ }
+ out->cr();
+ }
+ }
+}
+#endif // #ifdef ASSERT
+
void PSParallelCompact::compact() {
// trace("5");
TraceTime tm("compaction phase", print_phases(), true, gclog_or_tty);
@@ -2666,6 +2723,8 @@
update_deferred_objects(cm, SpaceId(id));
}
}
+
+ DEBUG_ONLY(write_block_fill_histogram(gclog_or_tty));
}
#ifdef ASSERT
@@ -3130,6 +3189,57 @@
} while (true);
}
+void PSParallelCompact::fill_blocks(size_t region_idx)
+{
+ // Fill in the block table elements for the specified region. Each block
+ // table element holds the number of live words in the region that are to the
+ // left of the first object that starts in the block. Thus only blocks in
+ // which an object starts need to be filled.
+ //
+ // The algorithm scans the section of the bitmap that corresponds to the
+ // region, keeping a running total of the live words. When an object start is
+ // found, if it's the first to start in the block that contains it, the
+ // current total is written to the block table element.
+ const size_t Log2BlockSize = ParallelCompactData::Log2BlockSize;
+ const size_t Log2RegionSize = ParallelCompactData::Log2RegionSize;
+ const size_t RegionSize = ParallelCompactData::RegionSize;
+
+ ParallelCompactData& sd = summary_data();
+ const size_t partial_obj_size = sd.region(region_idx)->partial_obj_size();
+ if (partial_obj_size >= RegionSize) {
+ return; // No objects start in this region.
+ }
+
+ // Ensure the first loop iteration decides that the block has changed.
+ size_t cur_block = sd.block_count();
+
+ const ParMarkBitMap* const bitmap = mark_bitmap();
+
+ const size_t Log2BitsPerBlock = Log2BlockSize - LogMinObjAlignment;
+ assert((size_t)1 << Log2BitsPerBlock ==
+ bitmap->words_to_bits(ParallelCompactData::BlockSize), "sanity");
+
+ size_t beg_bit = bitmap->words_to_bits(region_idx << Log2RegionSize);
+ const size_t range_end = beg_bit + bitmap->words_to_bits(RegionSize);
+ size_t live_bits = bitmap->words_to_bits(partial_obj_size);
+ beg_bit = bitmap->find_obj_beg(beg_bit + live_bits, range_end);
+ while (beg_bit < range_end) {
+ const size_t new_block = beg_bit >> Log2BitsPerBlock;
+ if (new_block != cur_block) {
+ cur_block = new_block;
+ sd.block(cur_block)->set_offset(bitmap->bits_to_words(live_bits));
+ }
+
+ const size_t end_bit = bitmap->find_obj_end(beg_bit, range_end);
+ if (end_bit < range_end - 1) {
+ live_bits += end_bit - beg_bit + 1;
+ beg_bit = bitmap->find_obj_beg(end_bit + 1, range_end);
+ } else {
+ return;
+ }
+ }
+}
+
void
PSParallelCompact::move_and_update(ParCompactionManager* cm, SpaceId space_id) {
const MutableSpace* sp = space(space_id);
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.hpp Fri May 31 10:04:00 2013 -0700
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.hpp Sat Jun 01 10:00:56 2013 +0200
@@ -220,6 +220,17 @@
// Mask for the bits in a pointer to get the address of the start of a region.
static const size_t RegionAddrMask;
+ static const size_t Log2BlockSize;
+ static const size_t BlockSize;
+ static const size_t BlockSizeBytes;
+
+ static const size_t BlockSizeOffsetMask;
+ static const size_t BlockAddrOffsetMask;
+ static const size_t BlockAddrMask;
+
+ static const size_t BlocksPerRegion;
+ static const size_t Log2BlocksPerRegion;
+
class RegionData
{
public:
@@ -272,6 +283,12 @@
inline uint destination_count() const;
inline uint destination_count_raw() const;
+ // Whether the block table for this region has been filled.
+ inline bool blocks_filled() const;
+
+ // Number of times the block table was filled.
+ DEBUG_ONLY(inline size_t blocks_filled_count() const;)
+
// The location of the java heap data that corresponds to this region.
inline HeapWord* data_location() const;
@@ -296,6 +313,7 @@
void set_partial_obj_size(size_t words) {
_partial_obj_size = (region_sz_t) words;
}
+ inline void set_blocks_filled();
inline void set_destination_count(uint count);
inline void set_live_obj_size(size_t words);
@@ -328,7 +346,11 @@
HeapWord* _partial_obj_addr;
region_sz_t _partial_obj_size;
region_sz_t volatile _dc_and_los;
+ bool _blocks_filled;
+
#ifdef ASSERT
+ size_t _blocks_filled_count; // Number of block table fills.
+
// These enable optimizations that are only partially implemented. Use
// debug builds to prevent the code fragments from breaking.
HeapWord* _data_location;
@@ -337,11 +359,26 @@
#ifdef ASSERT
public:
- uint _pushed; // 0 until region is pushed onto a worker's stack
+ uint _pushed; // 0 until region is pushed onto a stack
private:
#endif
};
+ // "Blocks" allow shorter sections of the bitmap to be searched. Each Block
+ // holds an offset, which is the amount of live data in the Region to the left
+ // of the first live object that starts in the Block.
+ class BlockData
+ {
+ public:
+ typedef unsigned short int blk_ofs_t;
+
+ blk_ofs_t offset() const { return _offset; }
+ void set_offset(size_t val) { _offset = (blk_ofs_t)val; }
+
+ private:
+ blk_ofs_t _offset;
+ };
+
public:
ParallelCompactData();
bool initialize(MemRegion covered_region);
@@ -353,8 +390,9 @@
inline RegionData* region(size_t region_idx) const;
inline size_t region(const RegionData* const region_ptr) const;
- // Returns true if the given address is contained within the region
- bool region_contains(size_t region_index, HeapWord* addr);
+ size_t block_count() const { return _block_count; }
+ inline BlockData* block(size_t block_idx) const;
+ inline size_t block(const BlockData* block_ptr) const;
void add_obj(HeapWord* addr, size_t len);
void add_obj(oop p, size_t len) { add_obj((HeapWord*)p, len); }
@@ -394,11 +432,24 @@
inline HeapWord* region_align_up(HeapWord* addr) const;
inline bool is_region_aligned(HeapWord* addr) const;
+ // Analogous to region_offset() for blocks.
+ size_t block_offset(const HeapWord* addr) const;
+ size_t addr_to_block_idx(const HeapWord* addr) const;
+ size_t addr_to_block_idx(const oop obj) const {
+ return addr_to_block_idx((HeapWord*) obj);
+ }
+ inline BlockData* addr_to_block_ptr(const HeapWord* addr) const;
+ inline HeapWord* block_to_addr(size_t block) const;
+ inline size_t region_to_block_idx(size_t region) const;
+
+ inline HeapWord* block_align_down(HeapWord* addr) const;
+ inline HeapWord* block_align_up(HeapWord* addr) const;
+ inline bool is_block_aligned(HeapWord* addr) const;
+
// Return the address one past the end of the partial object.
HeapWord* partial_obj_end(size_t region_idx) const;
- // Return the new location of the object p after the
- // the compaction.
+ // Return the location of the object after compaction.
HeapWord* calc_new_pointer(HeapWord* addr);
HeapWord* calc_new_pointer(oop p) {
@@ -411,6 +462,7 @@
#endif // #ifdef ASSERT
private:
+ bool initialize_block_data();
bool initialize_region_data(size_t region_size);
PSVirtualSpace* create_vspace(size_t count, size_t element_size);
@@ -424,6 +476,10 @@
size_t _reserved_byte_size;
RegionData* _region_data;
size_t _region_count;
+
+ PSVirtualSpace* _block_vspace;
+ BlockData* _block_data;
+ size_t _block_count;
};
inline uint
@@ -438,6 +494,28 @@
return destination_count_raw() >> dc_shift;
}
+inline bool
+ParallelCompactData::RegionData::blocks_filled() const
+{
+ return _blocks_filled;
+}
+
+#ifdef ASSERT
+inline size_t
+ParallelCompactData::RegionData::blocks_filled_count() const
+{
+ return _blocks_filled_count;
+}
+#endif // #ifdef ASSERT
+
+inline void
+ParallelCompactData::RegionData::set_blocks_filled()
+{
+ _blocks_filled = true;
+ // Debug builds count the number of times the table was filled.
+ DEBUG_ONLY(Atomic::inc_ptr(&_blocks_filled_count));
+}
+
inline void
ParallelCompactData::RegionData::set_destination_count(uint count)
{
@@ -532,6 +610,12 @@
return pointer_delta(region_ptr, _region_data, sizeof(RegionData));
}
+inline ParallelCompactData::BlockData*
+ParallelCompactData::block(size_t n) const {
+ assert(n < block_count(), "bad arg");
+ return _block_data + n;
+}
+
inline size_t
ParallelCompactData::region_offset(const HeapWord* addr) const
{
@@ -598,6 +682,63 @@
return region_offset(addr) == 0;
}
+inline size_t
+ParallelCompactData::block_offset(const HeapWord* addr) const
+{
+ assert(addr >= _region_start, "bad addr");
+ assert(addr <= _region_end, "bad addr");
+ return (size_t(addr) & BlockAddrOffsetMask) >> LogHeapWordSize;
+}
+
+inline size_t
+ParallelCompactData::addr_to_block_idx(const HeapWord* addr) const
+{
+ assert(addr >= _region_start, "bad addr");
+ assert(addr <= _region_end, "bad addr");
+ return pointer_delta(addr, _region_start) >> Log2BlockSize;
+}
+
+inline ParallelCompactData::BlockData*
+ParallelCompactData::addr_to_block_ptr(const HeapWord* addr) const
+{
+ return block(addr_to_block_idx(addr));
+}
+
+inline HeapWord*
+ParallelCompactData::block_to_addr(size_t block) const
+{
+ assert(block < _block_count, "block out of range");
+ return _region_start + (block << Log2BlockSize);
+}
+
+inline size_t
+ParallelCompactData::region_to_block_idx(size_t region) const
+{
+ return region << Log2BlocksPerRegion;
+}
+
+inline HeapWord*
+ParallelCompactData::block_align_down(HeapWord* addr) const
+{
+ assert(addr >= _region_start, "bad addr");
+ assert(addr < _region_end + RegionSize, "bad addr");
+ return (HeapWord*)(size_t(addr) & BlockAddrMask);
+}
+
+inline HeapWord*
+ParallelCompactData::block_align_up(HeapWord* addr) const
+{
+ assert(addr >= _region_start, "bad addr");
+ assert(addr <= _region_end, "bad addr");
+ return block_align_down(addr + BlockSizeOffsetMask);
+}
+
+inline bool
+ParallelCompactData::is_block_aligned(HeapWord* addr) const
+{
+ return block_offset(addr) == 0;
+}
+
// Abstract closure for use with ParMarkBitMap::iterate(), which will invoke the
// do_addr() method.
//
@@ -775,6 +916,7 @@
// Convenient access to type names.
typedef ParMarkBitMap::idx_t idx_t;
typedef ParallelCompactData::RegionData RegionData;
+ typedef ParallelCompactData::BlockData BlockData;
typedef enum {
old_space_id, eden_space_id,
@@ -962,6 +1104,8 @@
// Adjust addresses in roots. Does not adjust addresses in heap.
static void adjust_roots();
+ DEBUG_ONLY(static void write_block_fill_histogram(outputStream* const out);)
+
// Move objects to new locations.
static void compact_perm(ParCompactionManager* cm);
static void compact();
@@ -1128,6 +1272,9 @@
fill_region(cm, region);
}
+ // Fill in the block table for the specified region.
+ static void fill_blocks(size_t region_idx);
+
// Update the deferred objects in the space.
static void update_deferred_objects(ParCompactionManager* cm, SpaceId id);
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.inline.hpp Fri May 31 10:04:00 2013 -0700
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.inline.hpp Sat Jun 01 10:00:56 2013 +0200
@@ -42,7 +42,7 @@
if (o->is_forwarded()) {
o = o->forwardee();
// Card mark
- if (PSScavenge::is_obj_in_young((HeapWord*) o)) {
+ if (PSScavenge::is_obj_in_young(o)) {
PSScavenge::card_table()->inline_write_ref_field_gc(p, o);
}
oopDesc::encode_store_heap_oop_not_null(p, o);
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.cpp Fri May 31 10:04:00 2013 -0700
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.cpp Sat Jun 01 10:00:56 2013 +0200
@@ -61,6 +61,7 @@
bool PSScavenge::_survivor_overflow = false;
uint PSScavenge::_tenuring_threshold = 0;
HeapWord* PSScavenge::_young_generation_boundary = NULL;
+uintptr_t PSScavenge::_young_generation_boundary_compressed = 0;
elapsedTimer PSScavenge::_accumulated_time;
Stack<markOop, mtGC> PSScavenge::_preserved_mark_stack;
Stack<oop, mtGC> PSScavenge::_preserved_oop_stack;
@@ -71,7 +72,7 @@
class PSIsAliveClosure: public BoolObjectClosure {
public:
bool do_object_b(oop p) {
- return (!PSScavenge::is_obj_in_young((HeapWord*) p)) || p->is_forwarded();
+ return (!PSScavenge::is_obj_in_young(p)) || p->is_forwarded();
}
};
@@ -815,7 +816,7 @@
// Set boundary between young_gen and old_gen
assert(old_gen->reserved().end() <= young_gen->eden_space()->bottom(),
"old above young");
- _young_generation_boundary = young_gen->eden_space()->bottom();
+ set_young_generation_boundary(young_gen->eden_space()->bottom());
// Initialize ref handling object for scavenging.
MemRegion mr = young_gen->reserved();
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.hpp Fri May 31 10:04:00 2013 -0700
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.hpp Sat Jun 01 10:00:56 2013 +0200
@@ -62,19 +62,22 @@
protected:
// Flags/counters
- static ReferenceProcessor* _ref_processor; // Reference processor for scavenging.
- static PSIsAliveClosure _is_alive_closure; // Closure used for reference processing
- static CardTableExtension* _card_table; // We cache the card table for fast access.
- static bool _survivor_overflow; // Overflow this collection
- static uint _tenuring_threshold; // tenuring threshold for next scavenge
- static elapsedTimer _accumulated_time; // total time spent on scavenge
- static HeapWord* _young_generation_boundary; // The lowest address possible for the young_gen.
- // This is used to decide if an oop should be scavenged,
- // cards should be marked, etc.
+ static ReferenceProcessor* _ref_processor; // Reference processor for scavenging.
+ static PSIsAliveClosure _is_alive_closure; // Closure used for reference processing
+ static CardTableExtension* _card_table; // We cache the card table for fast access.
+ static bool _survivor_overflow; // Overflow this collection
+ static uint _tenuring_threshold; // tenuring threshold for next scavenge
+ static elapsedTimer _accumulated_time; // total time spent on scavenge
+ // The lowest address possible for the young_gen.
+ // This is used to decide if an oop should be scavenged,
+ // cards should be marked, etc.
+ static HeapWord* _young_generation_boundary;
+ // Used to optimize compressed oops young gen boundary checking.
+ static uintptr_t _young_generation_boundary_compressed;
static Stack<markOop, mtGC> _preserved_mark_stack; // List of marks to be restored after failed promotion
static Stack<oop, mtGC> _preserved_oop_stack; // List of oops that need their mark restored.
- static CollectorCounters* _counters; // collector performance counters
- static bool _promotion_failed;
+ static CollectorCounters* _counters; // collector performance counters
+ static bool _promotion_failed;
static void clean_up_failed_promotion();
@@ -112,6 +115,9 @@
// boundary moves, _young_generation_boundary must be reset
static void set_young_generation_boundary(HeapWord* v) {
_young_generation_boundary = v;
+ if (UseCompressedOops) {
+ _young_generation_boundary_compressed = (uintptr_t)oopDesc::encode_heap_oop((oop)v);
+ }
}
// Called by parallelScavengeHeap to init the tenuring threshold
@@ -140,11 +146,19 @@
static void copy_and_push_safe_barrier_from_klass(PSPromotionManager* pm, oop* p);
// Is an object in the young generation
- // This assumes that the HeapWord argument is in the heap,
+ // This assumes that the 'o' is in the heap,
// so it only checks one side of the complete predicate.
+
+ inline static bool is_obj_in_young(oop o) {
+ return (HeapWord*)o >= _young_generation_boundary;
+ }
+
+ inline static bool is_obj_in_young(narrowOop o) {
+ return (uintptr_t)o >= _young_generation_boundary_compressed;
+ }
+
inline static bool is_obj_in_young(HeapWord* o) {
- const bool result = (o >= _young_generation_boundary);
- return result;
+ return o >= _young_generation_boundary;
}
};
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.inline.hpp Fri May 31 10:04:00 2013 -0700
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.inline.hpp Sat Jun 01 10:00:56 2013 +0200
@@ -39,9 +39,7 @@
template <class T> inline bool PSScavenge::should_scavenge(T* p) {
T heap_oop = oopDesc::load_heap_oop(p);
- if (oopDesc::is_null(heap_oop)) return false;
- oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
- return PSScavenge::is_obj_in_young((HeapWord*)obj);
+ return PSScavenge::is_obj_in_young(heap_oop);
}
template <class T>
@@ -94,7 +92,7 @@
// or from metadata.
if ((!PSScavenge::is_obj_in_young((HeapWord*)p)) &&
Universe::heap()->is_in_reserved(p)) {
- if (PSScavenge::is_obj_in_young((HeapWord*)new_obj)) {
+ if (PSScavenge::is_obj_in_young(new_obj)) {
card_table()->inline_write_ref_field_gc(p, new_obj);
}
}
@@ -147,7 +145,7 @@
}
oopDesc::encode_store_heap_oop_not_null(p, new_obj);
- if (PSScavenge::is_obj_in_young((HeapWord*)new_obj)) {
+ if (PSScavenge::is_obj_in_young(new_obj)) {
do_klass_barrier();
}
}