src/share/vm/memory/space.inline.hpp

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rev 7084 : [mq]: demacro

*** 23,308 **** */ #ifndef SHARE_VM_MEMORY_SPACE_INLINE_HPP #define SHARE_VM_MEMORY_SPACE_INLINE_HPP #include "gc_interface/collectedHeap.hpp" #include "memory/space.hpp" #include "memory/universe.hpp" #include "runtime/prefetch.inline.hpp" #include "runtime/safepoint.hpp" inline HeapWord* Space::block_start(const void* p) { return block_start_const(p); } - #define SCAN_AND_FORWARD(cp,scan_limit,block_is_obj,block_size) { \ - /* Compute the new addresses for the live objects and store it in the mark \ - * Used by universe::mark_sweep_phase2() \ - */ \ - HeapWord* compact_top; /* This is where we are currently compacting to. */ \ - \ - /* We're sure to be here before any objects are compacted into this \ - * space, so this is a good time to initialize this: \ - */ \ - set_compaction_top(bottom()); \ - \ - if (cp->space == NULL) { \ - assert(cp->gen != NULL, "need a generation"); \ - assert(cp->threshold == NULL, "just checking"); \ - assert(cp->gen->first_compaction_space() == this, "just checking"); \ - cp->space = cp->gen->first_compaction_space(); \ - compact_top = cp->space->bottom(); \ - cp->space->set_compaction_top(compact_top); \ - cp->threshold = cp->space->initialize_threshold(); \ - } else { \ - compact_top = cp->space->compaction_top(); \ - } \ - \ - /* We allow some amount of garbage towards the bottom of the space, so \ - * we don't start compacting before there is a significant gain to be made.\ - * Occasionally, we want to ensure a full compaction, which is determined \ - * by the MarkSweepAlwaysCompactCount parameter. \ - */ \ - uint invocations = MarkSweep::total_invocations(); \ - bool skip_dead = ((invocations % MarkSweepAlwaysCompactCount) != 0); \ - \ - size_t allowed_deadspace = 0; \ - if (skip_dead) { \ - const size_t ratio = allowed_dead_ratio(); \ - allowed_deadspace = (capacity() * ratio / 100) / HeapWordSize; \ - } \ - \ - HeapWord* q = bottom(); \ - HeapWord* t = scan_limit(); \ - \ - HeapWord* end_of_live= q; /* One byte beyond the last byte of the last \ - live object. */ \ - HeapWord* first_dead = end();/* The first dead object. */ \ - LiveRange* liveRange = NULL; /* The current live range, recorded in the \ - first header of preceding free area. */ \ - _first_dead = first_dead; \ - \ - const intx interval = PrefetchScanIntervalInBytes; \ - \ - while (q < t) { \ - assert(!block_is_obj(q) || \ - oop(q)->mark()->is_marked() || oop(q)->mark()->is_unlocked() || \ - oop(q)->mark()->has_bias_pattern(), \ - "these are the only valid states during a mark sweep"); \ - if (block_is_obj(q) && oop(q)->is_gc_marked()) { \ - /* prefetch beyond q */ \ - Prefetch::write(q, interval); \ - size_t size = block_size(q); \ - compact_top = cp->space->forward(oop(q), size, cp, compact_top); \ - q += size; \ - end_of_live = q; \ - } else { \ - /* run over all the contiguous dead objects */ \ - HeapWord* end = q; \ - do { \ - /* prefetch beyond end */ \ - Prefetch::write(end, interval); \ - end += block_size(end); \ - } while (end < t && (!block_is_obj(end) || !oop(end)->is_gc_marked()));\ - \ - /* see if we might want to pretend this object is alive so that \ - * we don't have to compact quite as often. \ - */ \ - if (allowed_deadspace > 0 && q == compact_top) { \ - size_t sz = pointer_delta(end, q); \ - if (insert_deadspace(allowed_deadspace, q, sz)) { \ - compact_top = cp->space->forward(oop(q), sz, cp, compact_top); \ - q = end; \ - end_of_live = end; \ - continue; \ - } \ - } \ - \ - /* otherwise, it really is a free region. */ \ - \ - /* for the previous LiveRange, record the end of the live objects. */ \ - if (liveRange) { \ - liveRange->set_end(q); \ - } \ - \ - /* record the current LiveRange object. \ - * liveRange->start() is overlaid on the mark word. \ - */ \ - liveRange = (LiveRange*)q; \ - liveRange->set_start(end); \ - liveRange->set_end(end); \ - \ - /* see if this is the first dead region. */ \ - if (q < first_dead) { \ - first_dead = q; \ - } \ - \ - /* move on to the next object */ \ - q = end; \ - } \ - } \ - \ - assert(q == t, "just checking"); \ - if (liveRange != NULL) { \ - liveRange->set_end(q); \ - } \ - _end_of_live = end_of_live; \ - if (end_of_live < first_dead) { \ - first_dead = end_of_live; \ - } \ - _first_dead = first_dead; \ - \ - /* save the compaction_top of the compaction space. */ \ - cp->space->set_compaction_top(compact_top); \ - } - - #define SCAN_AND_ADJUST_POINTERS(adjust_obj_size) { \ - /* adjust all the interior pointers to point at the new locations of objects \ - * Used by MarkSweep::mark_sweep_phase3() */ \ - \ - HeapWord* q = bottom(); \ - HeapWord* t = _end_of_live; /* Established by "prepare_for_compaction". */ \ - \ - assert(_first_dead <= _end_of_live, "Stands to reason, no?"); \ - \ - if (q < t && _first_dead > q && \ - !oop(q)->is_gc_marked()) { \ - /* we have a chunk of the space which hasn't moved and we've \ - * reinitialized the mark word during the previous pass, so we can't \ - * use is_gc_marked for the traversal. */ \ - HeapWord* end = _first_dead; \ - \ - while (q < end) { \ - /* I originally tried to conjoin "block_start(q) == q" to the \ - * assertion below, but that doesn't work, because you can't \ - * accurately traverse previous objects to get to the current one \ - * after their pointers have been \ - * updated, until the actual compaction is done. dld, 4/00 */ \ - assert(block_is_obj(q), \ - "should be at block boundaries, and should be looking at objs"); \ - \ - /* point all the oops to the new location */ \ - size_t size = oop(q)->adjust_pointers(); \ - size = adjust_obj_size(size); \ - \ - q += size; \ - } \ - \ - if (_first_dead == t) { \ - q = t; \ - } else { \ - /* $$$ This is funky. Using this to read the previously written \ - * LiveRange. See also use below. */ \ - q = (HeapWord*)oop(_first_dead)->mark()->decode_pointer(); \ - } \ - } \ - \ - const intx interval = PrefetchScanIntervalInBytes; \ - \ - debug_only(HeapWord* prev_q = NULL); \ - while (q < t) { \ - /* prefetch beyond q */ \ - Prefetch::write(q, interval); \ - if (oop(q)->is_gc_marked()) { \ - /* q is alive */ \ - /* point all the oops to the new location */ \ - size_t size = oop(q)->adjust_pointers(); \ - size = adjust_obj_size(size); \ - debug_only(prev_q = q); \ - q += size; \ - } else { \ - /* q is not a live object, so its mark should point at the next \ - * live object */ \ - debug_only(prev_q = q); \ - q = (HeapWord*) oop(q)->mark()->decode_pointer(); \ - assert(q > prev_q, "we should be moving forward through memory"); \ - } \ - } \ - \ - assert(q == t, "just checking"); \ - } - - #define SCAN_AND_COMPACT(obj_size) { \ - /* Copy all live objects to their new location \ - * Used by MarkSweep::mark_sweep_phase4() */ \ - \ - HeapWord* q = bottom(); \ - HeapWord* const t = _end_of_live; \ - debug_only(HeapWord* prev_q = NULL); \ - \ - if (q < t && _first_dead > q && \ - !oop(q)->is_gc_marked()) { \ - debug_only( \ - /* we have a chunk of the space which hasn't moved and we've reinitialized \ - * the mark word during the previous pass, so we can't use is_gc_marked for \ - * the traversal. */ \ - HeapWord* const end = _first_dead; \ - \ - while (q < end) { \ - size_t size = obj_size(q); \ - assert(!oop(q)->is_gc_marked(), \ - "should be unmarked (special dense prefix handling)"); \ - debug_only(prev_q = q); \ - q += size; \ - } \ - ) /* debug_only */ \ - \ - if (_first_dead == t) { \ - q = t; \ - } else { \ - /* $$$ Funky */ \ - q = (HeapWord*) oop(_first_dead)->mark()->decode_pointer(); \ - } \ - } \ - \ - const intx scan_interval = PrefetchScanIntervalInBytes; \ - const intx copy_interval = PrefetchCopyIntervalInBytes; \ - while (q < t) { \ - if (!oop(q)->is_gc_marked()) { \ - /* mark is pointer to next marked oop */ \ - debug_only(prev_q = q); \ - q = (HeapWord*) oop(q)->mark()->decode_pointer(); \ - assert(q > prev_q, "we should be moving forward through memory"); \ - } else { \ - /* prefetch beyond q */ \ - Prefetch::read(q, scan_interval); \ - \ - /* size and destination */ \ - size_t size = obj_size(q); \ - HeapWord* compaction_top = (HeapWord*)oop(q)->forwardee(); \ - \ - /* prefetch beyond compaction_top */ \ - Prefetch::write(compaction_top, copy_interval); \ - \ - /* copy object and reinit its mark */ \ - assert(q != compaction_top, "everything in this pass should be moving"); \ - Copy::aligned_conjoint_words(q, compaction_top, size); \ - oop(compaction_top)->init_mark(); \ - assert(oop(compaction_top)->klass() != NULL, "should have a class"); \ - \ - debug_only(prev_q = q); \ - q += size; \ - } \ - } \ - \ - /* Let's remember if we were empty before we did the compaction. */ \ - bool was_empty = used_region().is_empty(); \ - /* Reset space after compaction is complete */ \ - reset_after_compaction(); \ - /* We do this clear, below, since it has overloaded meanings for some */ \ - /* space subtypes. For example, OffsetTableContigSpace's that were */ \ - /* compacted into will have had their offset table thresholds updated */ \ - /* continuously, but those that weren't need to have their thresholds */ \ - /* re-initialized. Also mangles unused area for debugging. */ \ - if (used_region().is_empty()) { \ - if (!was_empty) clear(SpaceDecorator::Mangle); \ - } else { \ - if (ZapUnusedHeapArea) mangle_unused_area(); \ - } \ - } - inline HeapWord* OffsetTableContigSpace::allocate(size_t size) { HeapWord* res = ContiguousSpace::allocate(size); if (res != NULL) { _offsets.alloc_block(res, size); } --- 23,45 ---- */ #ifndef SHARE_VM_MEMORY_SPACE_INLINE_HPP #define SHARE_VM_MEMORY_SPACE_INLINE_HPP + #include "gc_implementation/shared/liveRange.hpp" + #include "gc_implementation/shared/markSweep.inline.hpp" + #include "gc_implementation/shared/spaceDecorator.hpp" #include "gc_interface/collectedHeap.hpp" #include "memory/space.hpp" #include "memory/universe.hpp" #include "runtime/prefetch.inline.hpp" #include "runtime/safepoint.hpp" inline HeapWord* Space::block_start(const void* p) { return block_start_const(p); } inline HeapWord* OffsetTableContigSpace::allocate(size_t size) { HeapWord* res = ContiguousSpace::allocate(size); if (res != NULL) { _offsets.alloc_block(res, size); }
*** 332,337 **** --- 69,333 ---- inline HeapWord* OffsetTableContigSpace::block_start_const(const void* p) const { return _offsets.block_start(p); } + template <class SpaceType> + inline void CompactibleSpace::scan_and_forward(SpaceType* space, CompactPoint* cp) { + // Compute the new addresses for the live objects and store it in the mark + // Used by universe::mark_sweep_phase2() + HeapWord* compact_top; // This is where we are currently compacting to. + + // We're sure to be here before any objects are compacted into this + // space, so this is a good time to initialize this: + space->set_compaction_top(space->bottom()); + + if (cp->space == NULL) { + assert(cp->gen != NULL, "need a generation"); + assert(cp->threshold == NULL, "just checking"); + assert(cp->gen->first_compaction_space() == space, "just checking"); + cp->space = cp->gen->first_compaction_space(); + compact_top = cp->space->bottom(); + cp->space->set_compaction_top(compact_top); + cp->threshold = cp->space->initialize_threshold(); + } else { + compact_top = cp->space->compaction_top(); + } + + // We allow some amount of garbage towards the bottom of the space, so + // we don't start compacting before there is a significant gain to be made.\ + // Occasionally, we want to ensure a full compaction, which is determined + // by the MarkSweepAlwaysCompactCount parameter. + uint invocations = MarkSweep::total_invocations(); + bool skip_dead = ((invocations % MarkSweepAlwaysCompactCount) != 0); + + size_t allowed_deadspace = 0; + if (skip_dead) { + const size_t ratio = space->allowed_dead_ratio(); + allowed_deadspace = (space->capacity() * ratio / 100) / HeapWordSize; + } + + HeapWord* q = space->bottom(); + HeapWord* t = space->scan_limit(); + + HeapWord* end_of_live= q; // One byte beyond the last byte of the last + // live object. + HeapWord* first_dead = space->end(); // The first dead object. + LiveRange* liveRange = NULL; // The current live range, recorded in the + // first header of preceding free area. + space->_first_dead = first_dead; + + const intx interval = PrefetchScanIntervalInBytes; + + while (q < t) { + assert(!space->scanned_block_is_obj(q) || + oop(q)->mark()->is_marked() || oop(q)->mark()->is_unlocked() || + oop(q)->mark()->has_bias_pattern(), + "these are the only valid states during a mark sweep"); + if (space->scanned_block_is_obj(q) && oop(q)->is_gc_marked()) { + // prefetch beyond q + Prefetch::write(q, interval); + size_t size = space->scanned_block_size(q); + compact_top = cp->space->forward(oop(q), size, cp, compact_top); + q += size; + end_of_live = q; + } else { + // run over all the contiguous dead objects + HeapWord* end = q; + do { + // prefetch beyond end + Prefetch::write(end, interval); + end += space->scanned_block_size(end); + } while (end < t && (!space->scanned_block_is_obj(end) || !oop(end)->is_gc_marked())); + + // see if we might want to pretend this object is alive so that + // we don't have to compact quite as often. + if (allowed_deadspace > 0 && q == compact_top) { + size_t sz = pointer_delta(end, q); + if (space->insert_deadspace(allowed_deadspace, q, sz)) { + compact_top = cp->space->forward(oop(q), sz, cp, compact_top); + q = end; + end_of_live = end; + continue; + } + } + + // otherwise, it really is a free region. + + // for the previous LiveRange, record the end of the live objects. + if (liveRange) { + liveRange->set_end(q); + } + + // record the current LiveRange object. + // liveRange->start() is overlaid on the mark word. + liveRange = (LiveRange*)q; + liveRange->set_start(end); + liveRange->set_end(end); + + // see if this is the first dead region. + if (q < first_dead) { + first_dead = q; + } + + // move on to the next object + q = end; + } + } + + assert(q == t, "just checking"); + if (liveRange != NULL) { + liveRange->set_end(q); + } + space->_end_of_live = end_of_live; + if (end_of_live < first_dead) { + first_dead = end_of_live; + } + space->_first_dead = first_dead; + + // save the compaction_top of the compaction space. + cp->space->set_compaction_top(compact_top); + } + + template <class SpaceType> + inline void CompactibleSpace::scan_and_adjust_pointers(SpaceType* space) { + // adjust all the interior pointers to point at the new locations of objects + // Used by MarkSweep::mark_sweep_phase3() + + HeapWord* q = space->bottom(); + HeapWord* t = space->_end_of_live; // Established by "prepare_for_compaction". + + assert(space->_first_dead <= space->_end_of_live, "Stands to reason, no?"); + + if (q < t && space->_first_dead > q && !oop(q)->is_gc_marked()) { + // we have a chunk of the space which hasn't moved and we've + // reinitialized the mark word during the previous pass, so we can't + // use is_gc_marked for the traversal. + HeapWord* end = space->_first_dead; + + while (q < end) { + // I originally tried to conjoin "block_start(q) == q" to the + // assertion below, but that doesn't work, because you can't + // accurately traverse previous objects to get to the current one + // after their pointers have been + // updated, until the actual compaction is done. dld, 4/00 + assert(space->scanned_block_is_obj(q), "should be at block boundaries, and should be looking at objs"); + + // point all the oops to the new location + size_t size = oop(q)->adjust_pointers(); + size = space->adjust_obj_size(size); + + q += size; + } + + if (space->_first_dead == t) { + q = t; + } else { + // $$$ This is funky. Using this to read the previously written + // LiveRange. See also use below. + q = (HeapWord*)oop(space->_first_dead)->mark()->decode_pointer(); + } + } + + const intx interval = PrefetchScanIntervalInBytes; + + debug_only(HeapWord* prev_q = NULL); + while (q < t) { + // prefetch beyond q + Prefetch::write(q, interval); + if (oop(q)->is_gc_marked()) { + // q is alive + // point all the oops to the new location + size_t size = oop(q)->adjust_pointers(); + size = space->adjust_obj_size(size); + debug_only(prev_q = q); + q += size; + } else { + // q is not a live object, so its mark should point at the next + // live object + debug_only(prev_q = q); + q = (HeapWord*) oop(q)->mark()->decode_pointer(); + assert(q > prev_q, "we should be moving forward through memory"); + } + } + + assert(q == t, "just checking"); + } + + template <class SpaceType> + inline void CompactibleSpace::scan_and_compact(SpaceType* space) { + // Copy all live objects to their new location + // Used by MarkSweep::mark_sweep_phase4() + + HeapWord* q = space->bottom(); + HeapWord* const t = space->_end_of_live; + debug_only(HeapWord* prev_q = NULL); + + if (q < t && space->_first_dead > q && !oop(q)->is_gc_marked()) { + #ifdef ASSERT // Debug only + // we have a chunk of the space which hasn't moved and we've reinitialized + // the mark word during the previous pass, so we can't use is_gc_marked for + // the traversal. + HeapWord* const end = space->_first_dead; + + while (q < end) { + size_t size = space->obj_size(q); + assert(!oop(q)->is_gc_marked(), "should be unmarked (special dense prefix handling)"); + prev_q = q; + q += size; + } + #endif + + if (space->_first_dead == t) { + q = t; + } else { + // $$$ Funky + q = (HeapWord*) oop(space->_first_dead)->mark()->decode_pointer(); + } + } + + const intx scan_interval = PrefetchScanIntervalInBytes; + const intx copy_interval = PrefetchCopyIntervalInBytes; + while (q < t) { + if (!oop(q)->is_gc_marked()) { + // mark is pointer to next marked oop + debug_only(prev_q = q); + q = (HeapWord*) oop(q)->mark()->decode_pointer(); + assert(q > prev_q, "we should be moving forward through memory"); + } else { + // prefetch beyond q + Prefetch::read(q, scan_interval); + + // size and destination + size_t size = space->obj_size(q); + HeapWord* compaction_top = (HeapWord*)oop(q)->forwardee(); + + // prefetch beyond compaction_top + Prefetch::write(compaction_top, copy_interval); + + // copy object and reinit its mark + assert(q != compaction_top, "everything in this pass should be moving"); + Copy::aligned_conjoint_words(q, compaction_top, size); + oop(compaction_top)->init_mark(); + assert(oop(compaction_top)->klass() != NULL, "should have a class"); + + debug_only(prev_q = q); + q += size; + } + } + + // Let's remember if we were empty before we did the compaction. + bool was_empty = space->used_region().is_empty(); + // Reset space after compaction is complete + space->reset_after_compaction(); + // We do this clear, below, since it has overloaded meanings for some + // space subtypes. For example, OffsetTableContigSpace's that were + // compacted into will have had their offset table thresholds updated + // continuously, but those that weren't need to have their thresholds + // re-initialized. Also mangles unused area for debugging. + if (space->used_region().is_empty()) { + if (!was_empty) space->clear(SpaceDecorator::Mangle); + } else { + if (ZapUnusedHeapArea) space->mangle_unused_area(); + } + } #endif // SHARE_VM_MEMORY_SPACE_INLINE_HPP