Mercurial > hg > graal-compiler
changeset 1523:8bfe9058ca46 hs19-b01
Merge
| author | jcoomes |
|---|---|
| date | Thu, 13 May 2010 13:05:47 -0700 |
| parents | 67d74f7a15d9 (diff) ef1a1d051971 (current diff) |
| children | 093432aa7573 cc387008223e |
| files | src/share/vm/runtime/globals.hpp |
| diffstat | 13 files changed, 598 insertions(+), 477 deletions(-) [+] |
line wrap: on
line diff
--- a/src/cpu/sparc/vm/vm_version_sparc.cpp Wed May 12 22:06:02 2010 -0700 +++ b/src/cpu/sparc/vm/vm_version_sparc.cpp Thu May 13 13:05:47 2010 -0700 @@ -104,6 +104,12 @@ if (FLAG_IS_DEFAULT(OptoLoopAlignment)) { FLAG_SET_DEFAULT(OptoLoopAlignment, 4); } + // When using CMS, we cannot use memset() in BOT updates because + // the sun4v/CMT version in libc_psr uses BIS which exposes + // "phantom zeros" to concurrent readers. See 6948537. + if (FLAG_IS_DEFAULT(UseMemSetInBOT) && UseConcMarkSweepGC) { + FLAG_SET_DEFAULT(UseMemSetInBOT, false); + } } // Use hardware population count instruction if available.
--- a/src/os_cpu/linux_zero/vm/os_linux_zero.cpp Wed May 12 22:06:02 2010 -0700 +++ b/src/os_cpu/linux_zero/vm/os_linux_zero.cpp Thu May 13 13:05:47 2010 -0700 @@ -288,7 +288,7 @@ vm_exit_out_of_memory(0, "pthread_getattr_np"); } else { - fatal1("pthread_getattr_np failed with errno = %d", res); + fatal(err_msg("pthread_getattr_np failed with errno = %d", res)); } } @@ -296,7 +296,7 @@ size_t stack_bytes; res = pthread_attr_getstack(&attr, (void **) &stack_bottom, &stack_bytes); if (res != 0) { - fatal1("pthread_attr_getstack failed with errno = %d", res); + fatal(err_msg("pthread_attr_getstack failed with errno = %d", res)); } address stack_top = stack_bottom + stack_bytes; @@ -308,7 +308,7 @@ size_t guard_bytes; res = pthread_attr_getguardsize(&attr, &guard_bytes); if (res != 0) { - fatal1("pthread_attr_getguardsize failed with errno = %d", res); + fatal(err_msg("pthread_attr_getguardsize failed with errno = %d", res)); } int guard_pages = align_size_up(guard_bytes, page_bytes) / page_bytes; assert(guard_bytes == guard_pages * page_bytes, "unaligned guard");
--- a/src/share/vm/gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.cpp Wed May 12 22:06:02 2010 -0700 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.cpp Thu May 13 13:05:47 2010 -0700 @@ -1926,59 +1926,6 @@ ALL_SINCE_SAVE_MARKS_CLOSURES(CFLS_OOP_SINCE_SAVE_MARKS_DEFN) -////////////////////////////////////////////////////////////////////////////// -// We go over the list of promoted objects, removing each from the list, -// and applying the closure (this may, in turn, add more elements to -// the tail of the promoted list, and these newly added objects will -// also be processed) until the list is empty. -// To aid verification and debugging, in the non-product builds -// we actually forward _promoHead each time we process a promoted oop. -// Note that this is not necessary in general (i.e. when we don't need to -// call PromotionInfo::verify()) because oop_iterate can only add to the -// end of _promoTail, and never needs to look at _promoHead. - -#define PROMOTED_OOPS_ITERATE_DEFN(OopClosureType, nv_suffix) \ - \ -void PromotionInfo::promoted_oops_iterate##nv_suffix(OopClosureType* cl) { \ - NOT_PRODUCT(verify()); \ - PromotedObject *curObj, *nextObj; \ - for (curObj = _promoHead; curObj != NULL; curObj = nextObj) { \ - if ((nextObj = curObj->next()) == NULL) { \ - /* protect ourselves against additions due to closure application \ - below by resetting the list. */ \ - assert(_promoTail == curObj, "Should have been the tail"); \ - _promoHead = _promoTail = NULL; \ - } \ - if (curObj->hasDisplacedMark()) { \ - /* restore displaced header */ \ - oop(curObj)->set_mark(nextDisplacedHeader()); \ - } else { \ - /* restore prototypical header */ \ - oop(curObj)->init_mark(); \ - } \ - /* The "promoted_mark" should now not be set */ \ - assert(!curObj->hasPromotedMark(), \ - "Should have been cleared by restoring displaced mark-word"); \ - NOT_PRODUCT(_promoHead = nextObj); \ - if (cl != NULL) oop(curObj)->oop_iterate(cl); \ - if (nextObj == NULL) { /* start at head of list reset above */ \ - nextObj = _promoHead; \ - } \ - } \ - assert(noPromotions(), "post-condition violation"); \ - assert(_promoHead == NULL && _promoTail == NULL, "emptied promoted list");\ - assert(_spoolHead == _spoolTail, "emptied spooling buffers"); \ - assert(_firstIndex == _nextIndex, "empty buffer"); \ -} - -// This should have been ALL_SINCE_...() just like the others, -// but, because the body of the method above is somehwat longer, -// the MSVC compiler cannot cope; as a workaround, we split the -// macro into its 3 constituent parts below (see original macro -// definition in specializedOopClosures.hpp). -SPECIALIZED_SINCE_SAVE_MARKS_CLOSURES_YOUNG(PROMOTED_OOPS_ITERATE_DEFN) -PROMOTED_OOPS_ITERATE_DEFN(OopsInGenClosure,_v) - void CompactibleFreeListSpace::object_iterate_since_last_GC(ObjectClosure* cl) { // ugghh... how would one do this efficiently for a non-contiguous space? @@ -2506,281 +2453,6 @@ _dictionary->printDictCensus(); } -// Return the next displaced header, incrementing the pointer and -// recycling spool area as necessary. -markOop PromotionInfo::nextDisplacedHeader() { - assert(_spoolHead != NULL, "promotionInfo inconsistency"); - assert(_spoolHead != _spoolTail || _firstIndex < _nextIndex, - "Empty spool space: no displaced header can be fetched"); - assert(_spoolHead->bufferSize > _firstIndex, "Off by one error at head?"); - markOop hdr = _spoolHead->displacedHdr[_firstIndex]; - // Spool forward - if (++_firstIndex == _spoolHead->bufferSize) { // last location in this block - // forward to next block, recycling this block into spare spool buffer - SpoolBlock* tmp = _spoolHead->nextSpoolBlock; - assert(_spoolHead != _spoolTail, "Spooling storage mix-up"); - _spoolHead->nextSpoolBlock = _spareSpool; - _spareSpool = _spoolHead; - _spoolHead = tmp; - _firstIndex = 1; - NOT_PRODUCT( - if (_spoolHead == NULL) { // all buffers fully consumed - assert(_spoolTail == NULL && _nextIndex == 1, - "spool buffers processing inconsistency"); - } - ) - } - return hdr; -} - -void PromotionInfo::track(PromotedObject* trackOop) { - track(trackOop, oop(trackOop)->klass()); -} - -void PromotionInfo::track(PromotedObject* trackOop, klassOop klassOfOop) { - // make a copy of header as it may need to be spooled - markOop mark = oop(trackOop)->mark(); - trackOop->clearNext(); - if (mark->must_be_preserved_for_cms_scavenge(klassOfOop)) { - // save non-prototypical header, and mark oop - saveDisplacedHeader(mark); - trackOop->setDisplacedMark(); - } else { - // we'd like to assert something like the following: - // assert(mark == markOopDesc::prototype(), "consistency check"); - // ... but the above won't work because the age bits have not (yet) been - // cleared. The remainder of the check would be identical to the - // condition checked in must_be_preserved() above, so we don't really - // have anything useful to check here! - } - if (_promoTail != NULL) { - assert(_promoHead != NULL, "List consistency"); - _promoTail->setNext(trackOop); - _promoTail = trackOop; - } else { - assert(_promoHead == NULL, "List consistency"); - _promoHead = _promoTail = trackOop; - } - // Mask as newly promoted, so we can skip over such objects - // when scanning dirty cards - assert(!trackOop->hasPromotedMark(), "Should not have been marked"); - trackOop->setPromotedMark(); -} - -// Save the given displaced header, incrementing the pointer and -// obtaining more spool area as necessary. -void PromotionInfo::saveDisplacedHeader(markOop hdr) { - assert(_spoolHead != NULL && _spoolTail != NULL, - "promotionInfo inconsistency"); - assert(_spoolTail->bufferSize > _nextIndex, "Off by one error at tail?"); - _spoolTail->displacedHdr[_nextIndex] = hdr; - // Spool forward - if (++_nextIndex == _spoolTail->bufferSize) { // last location in this block - // get a new spooling block - assert(_spoolTail->nextSpoolBlock == NULL, "tail should terminate spool list"); - _splice_point = _spoolTail; // save for splicing - _spoolTail->nextSpoolBlock = getSpoolBlock(); // might fail - _spoolTail = _spoolTail->nextSpoolBlock; // might become NULL ... - // ... but will attempt filling before next promotion attempt - _nextIndex = 1; - } -} - -// Ensure that spooling space exists. Return false if spooling space -// could not be obtained. -bool PromotionInfo::ensure_spooling_space_work() { - assert(!has_spooling_space(), "Only call when there is no spooling space"); - // Try and obtain more spooling space - SpoolBlock* newSpool = getSpoolBlock(); - assert(newSpool == NULL || - (newSpool->bufferSize != 0 && newSpool->nextSpoolBlock == NULL), - "getSpoolBlock() sanity check"); - if (newSpool == NULL) { - return false; - } - _nextIndex = 1; - if (_spoolTail == NULL) { - _spoolTail = newSpool; - if (_spoolHead == NULL) { - _spoolHead = newSpool; - _firstIndex = 1; - } else { - assert(_splice_point != NULL && _splice_point->nextSpoolBlock == NULL, - "Splice point invariant"); - // Extra check that _splice_point is connected to list - #ifdef ASSERT - { - SpoolBlock* blk = _spoolHead; - for (; blk->nextSpoolBlock != NULL; - blk = blk->nextSpoolBlock); - assert(blk != NULL && blk == _splice_point, - "Splice point incorrect"); - } - #endif // ASSERT - _splice_point->nextSpoolBlock = newSpool; - } - } else { - assert(_spoolHead != NULL, "spool list consistency"); - _spoolTail->nextSpoolBlock = newSpool; - _spoolTail = newSpool; - } - return true; -} - -// Get a free spool buffer from the free pool, getting a new block -// from the heap if necessary. -SpoolBlock* PromotionInfo::getSpoolBlock() { - SpoolBlock* res; - if ((res = _spareSpool) != NULL) { - _spareSpool = _spareSpool->nextSpoolBlock; - res->nextSpoolBlock = NULL; - } else { // spare spool exhausted, get some from heap - res = (SpoolBlock*)(space()->allocateScratch(refillSize())); - if (res != NULL) { - res->init(); - } - } - assert(res == NULL || res->nextSpoolBlock == NULL, "postcondition"); - return res; -} - -void PromotionInfo::startTrackingPromotions() { - assert(_spoolHead == _spoolTail && _firstIndex == _nextIndex, - "spooling inconsistency?"); - _firstIndex = _nextIndex = 1; - _tracking = true; -} - -#define CMSPrintPromoBlockInfo 1 - -void PromotionInfo::stopTrackingPromotions(uint worker_id) { - assert(_spoolHead == _spoolTail && _firstIndex == _nextIndex, - "spooling inconsistency?"); - _firstIndex = _nextIndex = 1; - _tracking = false; - if (CMSPrintPromoBlockInfo > 1) { - print_statistics(worker_id); - } -} - -void PromotionInfo::print_statistics(uint worker_id) const { - assert(_spoolHead == _spoolTail && _firstIndex == _nextIndex, - "Else will undercount"); - assert(CMSPrintPromoBlockInfo > 0, "Else unnecessary call"); - // Count the number of blocks and slots in the free pool - size_t slots = 0; - size_t blocks = 0; - for (SpoolBlock* cur_spool = _spareSpool; - cur_spool != NULL; - cur_spool = cur_spool->nextSpoolBlock) { - // the first entry is just a self-pointer; indices 1 through - // bufferSize - 1 are occupied (thus, bufferSize - 1 slots). - guarantee((void*)cur_spool->displacedHdr == (void*)&cur_spool->displacedHdr, - "first entry of displacedHdr should be self-referential"); - slots += cur_spool->bufferSize - 1; - blocks++; - } - if (_spoolHead != NULL) { - slots += _spoolHead->bufferSize - 1; - blocks++; - } - gclog_or_tty->print_cr(" [worker %d] promo_blocks = %d, promo_slots = %d ", - worker_id, blocks, slots); -} - -// When _spoolTail is not NULL, then the slot <_spoolTail, _nextIndex> -// points to the next slot available for filling. -// The set of slots holding displaced headers are then all those in the -// right-open interval denoted by: -// -// [ <_spoolHead, _firstIndex>, <_spoolTail, _nextIndex> ) -// -// When _spoolTail is NULL, then the set of slots with displaced headers -// is all those starting at the slot <_spoolHead, _firstIndex> and -// going up to the last slot of last block in the linked list. -// In this lartter case, _splice_point points to the tail block of -// this linked list of blocks holding displaced headers. -void PromotionInfo::verify() const { - // Verify the following: - // 1. the number of displaced headers matches the number of promoted - // objects that have displaced headers - // 2. each promoted object lies in this space - debug_only( - PromotedObject* junk = NULL; - assert(junk->next_addr() == (void*)(oop(junk)->mark_addr()), - "Offset of PromotedObject::_next is expected to align with " - " the OopDesc::_mark within OopDesc"); - ) - // FIXME: guarantee???? - guarantee(_spoolHead == NULL || _spoolTail != NULL || - _splice_point != NULL, "list consistency"); - guarantee(_promoHead == NULL || _promoTail != NULL, "list consistency"); - // count the number of objects with displaced headers - size_t numObjsWithDisplacedHdrs = 0; - for (PromotedObject* curObj = _promoHead; curObj != NULL; curObj = curObj->next()) { - guarantee(space()->is_in_reserved((HeapWord*)curObj), "Containment"); - // the last promoted object may fail the mark() != NULL test of is_oop(). - guarantee(curObj->next() == NULL || oop(curObj)->is_oop(), "must be an oop"); - if (curObj->hasDisplacedMark()) { - numObjsWithDisplacedHdrs++; - } - } - // Count the number of displaced headers - size_t numDisplacedHdrs = 0; - for (SpoolBlock* curSpool = _spoolHead; - curSpool != _spoolTail && curSpool != NULL; - curSpool = curSpool->nextSpoolBlock) { - // the first entry is just a self-pointer; indices 1 through - // bufferSize - 1 are occupied (thus, bufferSize - 1 slots). - guarantee((void*)curSpool->displacedHdr == (void*)&curSpool->displacedHdr, - "first entry of displacedHdr should be self-referential"); - numDisplacedHdrs += curSpool->bufferSize - 1; - } - guarantee((_spoolHead == _spoolTail) == (numDisplacedHdrs == 0), - "internal consistency"); - guarantee(_spoolTail != NULL || _nextIndex == 1, - "Inconsistency between _spoolTail and _nextIndex"); - // We overcounted (_firstIndex-1) worth of slots in block - // _spoolHead and we undercounted (_nextIndex-1) worth of - // slots in block _spoolTail. We make an appropriate - // adjustment by subtracting the first and adding the - // second: - (_firstIndex - 1) + (_nextIndex - 1) - numDisplacedHdrs += (_nextIndex - _firstIndex); - guarantee(numDisplacedHdrs == numObjsWithDisplacedHdrs, "Displaced hdr count"); -} - -void PromotionInfo::print_on(outputStream* st) const { - SpoolBlock* curSpool = NULL; - size_t i = 0; - st->print_cr("start & end indices: [" SIZE_FORMAT ", " SIZE_FORMAT ")", - _firstIndex, _nextIndex); - for (curSpool = _spoolHead; curSpool != _spoolTail && curSpool != NULL; - curSpool = curSpool->nextSpoolBlock) { - curSpool->print_on(st); - st->print_cr(" active "); - i++; - } - for (curSpool = _spoolTail; curSpool != NULL; - curSpool = curSpool->nextSpoolBlock) { - curSpool->print_on(st); - st->print_cr(" inactive "); - i++; - } - for (curSpool = _spareSpool; curSpool != NULL; - curSpool = curSpool->nextSpoolBlock) { - curSpool->print_on(st); - st->print_cr(" free "); - i++; - } - st->print_cr(SIZE_FORMAT " header spooling blocks", i); -} - -void SpoolBlock::print_on(outputStream* st) const { - st->print("[" PTR_FORMAT "," PTR_FORMAT "), " SIZE_FORMAT " HeapWords -> " PTR_FORMAT, - this, (HeapWord*)displacedHdr + bufferSize, - bufferSize, nextSpoolBlock); -} - /////////////////////////////////////////////////////////////////////////// // CFLS_LAB ///////////////////////////////////////////////////////////////////////////
--- a/src/share/vm/gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.hpp Wed May 12 22:06:02 2010 -0700 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.hpp Thu May 13 13:05:47 2010 -0700 @@ -33,140 +33,6 @@ class ObjectClosureCareful; class Klass; -class PromotedObject VALUE_OBJ_CLASS_SPEC { - private: - enum { - promoted_mask = right_n_bits(2), // i.e. 0x3 - displaced_mark = nth_bit(2), // i.e. 0x4 - next_mask = ~(right_n_bits(3)) // i.e. ~(0x7) - }; - intptr_t _next; - public: - inline PromotedObject* next() const { - return (PromotedObject*)(_next & next_mask); - } - inline void setNext(PromotedObject* x) { - assert(((intptr_t)x & ~next_mask) == 0, - "Conflict in bit usage, " - " or insufficient alignment of objects"); - _next |= (intptr_t)x; - } - inline void setPromotedMark() { - _next |= promoted_mask; - } - inline bool hasPromotedMark() const { - return (_next & promoted_mask) == promoted_mask; - } - inline void setDisplacedMark() { - _next |= displaced_mark; - } - inline bool hasDisplacedMark() const { - return (_next & displaced_mark) != 0; - } - inline void clearNext() { _next = 0; } - debug_only(void *next_addr() { return (void *) &_next; }) -}; - -class SpoolBlock: public FreeChunk { - friend class PromotionInfo; - protected: - SpoolBlock* nextSpoolBlock; - size_t bufferSize; // number of usable words in this block - markOop* displacedHdr; // the displaced headers start here - - // Note about bufferSize: it denotes the number of entries available plus 1; - // legal indices range from 1 through BufferSize - 1. See the verification - // code verify() that counts the number of displaced headers spooled. - size_t computeBufferSize() { - return (size() * sizeof(HeapWord) - sizeof(*this)) / sizeof(markOop); - } - - public: - void init() { - bufferSize = computeBufferSize(); - displacedHdr = (markOop*)&displacedHdr; - nextSpoolBlock = NULL; - } - - void print_on(outputStream* st) const; - void print() const { print_on(gclog_or_tty); } -}; - -class PromotionInfo VALUE_OBJ_CLASS_SPEC { - bool _tracking; // set if tracking - CompactibleFreeListSpace* _space; // the space to which this belongs - PromotedObject* _promoHead; // head of list of promoted objects - PromotedObject* _promoTail; // tail of list of promoted objects - SpoolBlock* _spoolHead; // first spooling block - SpoolBlock* _spoolTail; // last non-full spooling block or null - SpoolBlock* _splice_point; // when _spoolTail is null, holds list tail - SpoolBlock* _spareSpool; // free spool buffer - size_t _firstIndex; // first active index in - // first spooling block (_spoolHead) - size_t _nextIndex; // last active index + 1 in last - // spooling block (_spoolTail) - private: - // ensure that spooling space exists; return true if there is spooling space - bool ensure_spooling_space_work(); - - public: - PromotionInfo() : - _tracking(0), _space(NULL), - _promoHead(NULL), _promoTail(NULL), - _spoolHead(NULL), _spoolTail(NULL), - _spareSpool(NULL), _firstIndex(1), - _nextIndex(1) {} - - bool noPromotions() const { - assert(_promoHead != NULL || _promoTail == NULL, "list inconsistency"); - return _promoHead == NULL; - } - void startTrackingPromotions(); - void stopTrackingPromotions(uint worker_id = 0); - bool tracking() const { return _tracking; } - void track(PromotedObject* trackOop); // keep track of a promoted oop - // The following variant must be used when trackOop is not fully - // initialized and has a NULL klass: - void track(PromotedObject* trackOop, klassOop klassOfOop); // keep track of a promoted oop - void setSpace(CompactibleFreeListSpace* sp) { _space = sp; } - CompactibleFreeListSpace* space() const { return _space; } - markOop nextDisplacedHeader(); // get next header & forward spool pointer - void saveDisplacedHeader(markOop hdr); - // save header and forward spool - - inline size_t refillSize() const; - - SpoolBlock* getSpoolBlock(); // return a free spooling block - inline bool has_spooling_space() { - return _spoolTail != NULL && _spoolTail->bufferSize > _nextIndex; - } - // ensure that spooling space exists - bool ensure_spooling_space() { - return has_spooling_space() || ensure_spooling_space_work(); - } - #define PROMOTED_OOPS_ITERATE_DECL(OopClosureType, nv_suffix) \ - void promoted_oops_iterate##nv_suffix(OopClosureType* cl); - ALL_SINCE_SAVE_MARKS_CLOSURES(PROMOTED_OOPS_ITERATE_DECL) - #undef PROMOTED_OOPS_ITERATE_DECL - void promoted_oops_iterate(OopsInGenClosure* cl) { - promoted_oops_iterate_v(cl); - } - void verify() const; - void reset() { - _promoHead = NULL; - _promoTail = NULL; - _spoolHead = NULL; - _spoolTail = NULL; - _spareSpool = NULL; - _firstIndex = 0; - _nextIndex = 0; - - } - - void print_on(outputStream* st) const; - void print_statistics(uint worker_id) const; -}; - class LinearAllocBlock VALUE_OBJ_CLASS_SPEC { public: LinearAllocBlock() : _ptr(0), _word_size(0), _refillSize(0), @@ -557,6 +423,12 @@ // promoted since the most recent call to save_marks() on // this generation and has not subsequently been iterated // over (using oop_since_save_marks_iterate() above). + // This property holds only for single-threaded collections, + // and is typically used for Cheney scans; for MT scavenges, + // the property holds for all objects promoted during that + // scavenge for the duration of the scavenge and is used + // by card-scanning to avoid scanning objects (being) promoted + // during that scavenge. bool obj_allocated_since_save_marks(const oop obj) const { assert(is_in_reserved(obj), "Wrong space?"); return ((PromotedObject*)obj)->hasPromotedMark();
--- a/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp Wed May 12 22:06:02 2010 -0700 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp Thu May 13 13:05:47 2010 -0700 @@ -789,6 +789,14 @@ _gc_counters = new CollectorCounters("CMS", 1); _completed_initialization = true; _inter_sweep_timer.start(); // start of time +#ifdef SPARC + // Issue a stern warning, but allow use for experimentation and debugging. + if (VM_Version::is_sun4v() && UseMemSetInBOT) { + assert(!FLAG_IS_DEFAULT(UseMemSetInBOT), "Error"); + warning("Experimental flag -XX:+UseMemSetInBOT is known to cause instability" + " on sun4v; please understand that you are using at your own risk!"); + } +#endif } const char* ConcurrentMarkSweepGeneration::name() const { @@ -1356,7 +1364,7 @@ obj->set_mark(m); // Now we can track the promoted object, if necessary. We take care - // To delay the transition from uninitialized to full object + // to delay the transition from uninitialized to full object // (i.e., insertion of klass pointer) until after, so that it // atomically becomes a promoted object. if (promoInfo->tracking()) { @@ -1416,10 +1424,9 @@ bool CMSCollector::shouldConcurrentCollect() { if (_full_gc_requested) { - assert(ExplicitGCInvokesConcurrent, "Unexpected state"); if (Verbose && PrintGCDetails) { gclog_or_tty->print_cr("CMSCollector: collect because of explicit " - " gc request"); + " gc request (or gc_locker)"); } return true; }
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/promotionInfo.cpp Thu May 13 13:05:47 2010 -0700 @@ -0,0 +1,360 @@ +/* + * Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + */ + +# include "incls/_precompiled.incl" +# include "incls/_promotionInfo.cpp.incl" + +///////////////////////////////////////////////////////////////////////// +//// PromotionInfo +///////////////////////////////////////////////////////////////////////// + + +////////////////////////////////////////////////////////////////////////////// +// We go over the list of promoted objects, removing each from the list, +// and applying the closure (this may, in turn, add more elements to +// the tail of the promoted list, and these newly added objects will +// also be processed) until the list is empty. +// To aid verification and debugging, in the non-product builds +// we actually forward _promoHead each time we process a promoted oop. +// Note that this is not necessary in general (i.e. when we don't need to +// call PromotionInfo::verify()) because oop_iterate can only add to the +// end of _promoTail, and never needs to look at _promoHead. + +#define PROMOTED_OOPS_ITERATE_DEFN(OopClosureType, nv_suffix) \ + \ +void PromotionInfo::promoted_oops_iterate##nv_suffix(OopClosureType* cl) { \ + NOT_PRODUCT(verify()); \ + PromotedObject *curObj, *nextObj; \ + for (curObj = _promoHead; curObj != NULL; curObj = nextObj) { \ + if ((nextObj = curObj->next()) == NULL) { \ + /* protect ourselves against additions due to closure application \ + below by resetting the list. */ \ + assert(_promoTail == curObj, "Should have been the tail"); \ + _promoHead = _promoTail = NULL; \ + } \ + if (curObj->hasDisplacedMark()) { \ + /* restore displaced header */ \ + oop(curObj)->set_mark(nextDisplacedHeader()); \ + } else { \ + /* restore prototypical header */ \ + oop(curObj)->init_mark(); \ + } \ + /* The "promoted_mark" should now not be set */ \ + assert(!curObj->hasPromotedMark(), \ + "Should have been cleared by restoring displaced mark-word"); \ + NOT_PRODUCT(_promoHead = nextObj); \ + if (cl != NULL) oop(curObj)->oop_iterate(cl); \ + if (nextObj == NULL) { /* start at head of list reset above */ \ + nextObj = _promoHead; \ + } \ + } \ + assert(noPromotions(), "post-condition violation"); \ + assert(_promoHead == NULL && _promoTail == NULL, "emptied promoted list");\ + assert(_spoolHead == _spoolTail, "emptied spooling buffers"); \ + assert(_firstIndex == _nextIndex, "empty buffer"); \ +} + +// This should have been ALL_SINCE_...() just like the others, +// but, because the body of the method above is somehwat longer, +// the MSVC compiler cannot cope; as a workaround, we split the +// macro into its 3 constituent parts below (see original macro +// definition in specializedOopClosures.hpp). +SPECIALIZED_SINCE_SAVE_MARKS_CLOSURES_YOUNG(PROMOTED_OOPS_ITERATE_DEFN) +PROMOTED_OOPS_ITERATE_DEFN(OopsInGenClosure,_v) + + +// Return the next displaced header, incrementing the pointer and +// recycling spool area as necessary. +markOop PromotionInfo::nextDisplacedHeader() { + assert(_spoolHead != NULL, "promotionInfo inconsistency"); + assert(_spoolHead != _spoolTail || _firstIndex < _nextIndex, + "Empty spool space: no displaced header can be fetched"); + assert(_spoolHead->bufferSize > _firstIndex, "Off by one error at head?"); + markOop hdr = _spoolHead->displacedHdr[_firstIndex]; + // Spool forward + if (++_firstIndex == _spoolHead->bufferSize) { // last location in this block + // forward to next block, recycling this block into spare spool buffer + SpoolBlock* tmp = _spoolHead->nextSpoolBlock; + assert(_spoolHead != _spoolTail, "Spooling storage mix-up"); + _spoolHead->nextSpoolBlock = _spareSpool; + _spareSpool = _spoolHead; + _spoolHead = tmp; + _firstIndex = 1; + NOT_PRODUCT( + if (_spoolHead == NULL) { // all buffers fully consumed + assert(_spoolTail == NULL && _nextIndex == 1, + "spool buffers processing inconsistency"); + } + ) + } + return hdr; +} + +void PromotionInfo::track(PromotedObject* trackOop) { + track(trackOop, oop(trackOop)->klass()); +} + +void PromotionInfo::track(PromotedObject* trackOop, klassOop klassOfOop) { + // make a copy of header as it may need to be spooled + markOop mark = oop(trackOop)->mark(); + trackOop->clearNext(); + if (mark->must_be_preserved_for_cms_scavenge(klassOfOop)) { + // save non-prototypical header, and mark oop + saveDisplacedHeader(mark); + trackOop->setDisplacedMark(); + } else { + // we'd like to assert something like the following: + // assert(mark == markOopDesc::prototype(), "consistency check"); + // ... but the above won't work because the age bits have not (yet) been + // cleared. The remainder of the check would be identical to the + // condition checked in must_be_preserved() above, so we don't really + // have anything useful to check here! + } + if (_promoTail != NULL) { + assert(_promoHead != NULL, "List consistency"); + _promoTail->setNext(trackOop); + _promoTail = trackOop; + } else { + assert(_promoHead == NULL, "List consistency"); + _promoHead = _promoTail = trackOop; + } + // Mask as newly promoted, so we can skip over such objects + // when scanning dirty cards + assert(!trackOop->hasPromotedMark(), "Should not have been marked"); + trackOop->setPromotedMark(); +} + +// Save the given displaced header, incrementing the pointer and +// obtaining more spool area as necessary. +void PromotionInfo::saveDisplacedHeader(markOop hdr) { + assert(_spoolHead != NULL && _spoolTail != NULL, + "promotionInfo inconsistency"); + assert(_spoolTail->bufferSize > _nextIndex, "Off by one error at tail?"); + _spoolTail->displacedHdr[_nextIndex] = hdr; + // Spool forward + if (++_nextIndex == _spoolTail->bufferSize) { // last location in this block + // get a new spooling block + assert(_spoolTail->nextSpoolBlock == NULL, "tail should terminate spool list"); + _splice_point = _spoolTail; // save for splicing + _spoolTail->nextSpoolBlock = getSpoolBlock(); // might fail + _spoolTail = _spoolTail->nextSpoolBlock; // might become NULL ... + // ... but will attempt filling before next promotion attempt + _nextIndex = 1; + } +} + +// Ensure that spooling space exists. Return false if spooling space +// could not be obtained. +bool PromotionInfo::ensure_spooling_space_work() { + assert(!has_spooling_space(), "Only call when there is no spooling space"); + // Try and obtain more spooling space + SpoolBlock* newSpool = getSpoolBlock(); + assert(newSpool == NULL || + (newSpool->bufferSize != 0 && newSpool->nextSpoolBlock == NULL), + "getSpoolBlock() sanity check"); + if (newSpool == NULL) { + return false; + } + _nextIndex = 1; + if (_spoolTail == NULL) { + _spoolTail = newSpool; + if (_spoolHead == NULL) { + _spoolHead = newSpool; + _firstIndex = 1; + } else { + assert(_splice_point != NULL && _splice_point->nextSpoolBlock == NULL, + "Splice point invariant"); + // Extra check that _splice_point is connected to list + #ifdef ASSERT + { + SpoolBlock* blk = _spoolHead; + for (; blk->nextSpoolBlock != NULL; + blk = blk->nextSpoolBlock); + assert(blk != NULL && blk == _splice_point, + "Splice point incorrect"); + } + #endif // ASSERT + _splice_point->nextSpoolBlock = newSpool; + } + } else { + assert(_spoolHead != NULL, "spool list consistency"); + _spoolTail->nextSpoolBlock = newSpool; + _spoolTail = newSpool; + } + return true; +} + +// Get a free spool buffer from the free pool, getting a new block +// from the heap if necessary. +SpoolBlock* PromotionInfo::getSpoolBlock() { + SpoolBlock* res; + if ((res = _spareSpool) != NULL) { + _spareSpool = _spareSpool->nextSpoolBlock; + res->nextSpoolBlock = NULL; + } else { // spare spool exhausted, get some from heap + res = (SpoolBlock*)(space()->allocateScratch(refillSize())); + if (res != NULL) { + res->init(); + } + } + assert(res == NULL || res->nextSpoolBlock == NULL, "postcondition"); + return res; +} + +void PromotionInfo::startTrackingPromotions() { + assert(_spoolHead == _spoolTail && _firstIndex == _nextIndex, + "spooling inconsistency?"); + _firstIndex = _nextIndex = 1; + _tracking = true; +} + +#define CMSPrintPromoBlockInfo 1 + +void PromotionInfo::stopTrackingPromotions(uint worker_id) { + assert(_spoolHead == _spoolTail && _firstIndex == _nextIndex, + "spooling inconsistency?"); + _firstIndex = _nextIndex = 1; + _tracking = false; + if (CMSPrintPromoBlockInfo > 1) { + print_statistics(worker_id); + } +} + +void PromotionInfo::print_statistics(uint worker_id) const { + assert(_spoolHead == _spoolTail && _firstIndex == _nextIndex, + "Else will undercount"); + assert(CMSPrintPromoBlockInfo > 0, "Else unnecessary call"); + // Count the number of blocks and slots in the free pool + size_t slots = 0; + size_t blocks = 0; + for (SpoolBlock* cur_spool = _spareSpool; + cur_spool != NULL; + cur_spool = cur_spool->nextSpoolBlock) { + // the first entry is just a self-pointer; indices 1 through + // bufferSize - 1 are occupied (thus, bufferSize - 1 slots). + guarantee((void*)cur_spool->displacedHdr == (void*)&cur_spool->displacedHdr, + "first entry of displacedHdr should be self-referential"); + slots += cur_spool->bufferSize - 1; + blocks++; + } + if (_spoolHead != NULL) { + slots += _spoolHead->bufferSize - 1; + blocks++; + } + gclog_or_tty->print_cr(" [worker %d] promo_blocks = %d, promo_slots = %d ", + worker_id, blocks, slots); +} + +// When _spoolTail is not NULL, then the slot <_spoolTail, _nextIndex> +// points to the next slot available for filling. +// The set of slots holding displaced headers are then all those in the +// right-open interval denoted by: +// +// [ <_spoolHead, _firstIndex>, <_spoolTail, _nextIndex> ) +// +// When _spoolTail is NULL, then the set of slots with displaced headers +// is all those starting at the slot <_spoolHead, _firstIndex> and +// going up to the last slot of last block in the linked list. +// In this lartter case, _splice_point points to the tail block of +// this linked list of blocks holding displaced headers. +void PromotionInfo::verify() const { + // Verify the following: + // 1. the number of displaced headers matches the number of promoted + // objects that have displaced headers + // 2. each promoted object lies in this space + debug_only( + PromotedObject* junk = NULL; + assert(junk->next_addr() == (void*)(oop(junk)->mark_addr()), + "Offset of PromotedObject::_next is expected to align with " + " the OopDesc::_mark within OopDesc"); + ) + // FIXME: guarantee???? + guarantee(_spoolHead == NULL || _spoolTail != NULL || + _splice_point != NULL, "list consistency"); + guarantee(_promoHead == NULL || _promoTail != NULL, "list consistency"); + // count the number of objects with displaced headers + size_t numObjsWithDisplacedHdrs = 0; + for (PromotedObject* curObj = _promoHead; curObj != NULL; curObj = curObj->next()) { + guarantee(space()->is_in_reserved((HeapWord*)curObj), "Containment"); + // the last promoted object may fail the mark() != NULL test of is_oop(). + guarantee(curObj->next() == NULL || oop(curObj)->is_oop(), "must be an oop"); + if (curObj->hasDisplacedMark()) { + numObjsWithDisplacedHdrs++; + } + } + // Count the number of displaced headers + size_t numDisplacedHdrs = 0; + for (SpoolBlock* curSpool = _spoolHead; + curSpool != _spoolTail && curSpool != NULL; + curSpool = curSpool->nextSpoolBlock) { + // the first entry is just a self-pointer; indices 1 through + // bufferSize - 1 are occupied (thus, bufferSize - 1 slots). + guarantee((void*)curSpool->displacedHdr == (void*)&curSpool->displacedHdr, + "first entry of displacedHdr should be self-referential"); + numDisplacedHdrs += curSpool->bufferSize - 1; + } + guarantee((_spoolHead == _spoolTail) == (numDisplacedHdrs == 0), + "internal consistency"); + guarantee(_spoolTail != NULL || _nextIndex == 1, + "Inconsistency between _spoolTail and _nextIndex"); + // We overcounted (_firstIndex-1) worth of slots in block + // _spoolHead and we undercounted (_nextIndex-1) worth of + // slots in block _spoolTail. We make an appropriate + // adjustment by subtracting the first and adding the + // second: - (_firstIndex - 1) + (_nextIndex - 1) + numDisplacedHdrs += (_nextIndex - _firstIndex); + guarantee(numDisplacedHdrs == numObjsWithDisplacedHdrs, "Displaced hdr count"); +} + +void PromotionInfo::print_on(outputStream* st) const { + SpoolBlock* curSpool = NULL; + size_t i = 0; + st->print_cr("start & end indices: [" SIZE_FORMAT ", " SIZE_FORMAT ")", + _firstIndex, _nextIndex); + for (curSpool = _spoolHead; curSpool != _spoolTail && curSpool != NULL; + curSpool = curSpool->nextSpoolBlock) { + curSpool->print_on(st); + st->print_cr(" active "); + i++; + } + for (curSpool = _spoolTail; curSpool != NULL; + curSpool = curSpool->nextSpoolBlock) { + curSpool->print_on(st); + st->print_cr(" inactive "); + i++; + } + for (curSpool = _spareSpool; curSpool != NULL; + curSpool = curSpool->nextSpoolBlock) { + curSpool->print_on(st); + st->print_cr(" free "); + i++; + } + st->print_cr(SIZE_FORMAT " header spooling blocks", i); +} + +void SpoolBlock::print_on(outputStream* st) const { + st->print("[" PTR_FORMAT "," PTR_FORMAT "), " SIZE_FORMAT " HeapWords -> " PTR_FORMAT, + this, (HeapWord*)displacedHdr + bufferSize, + bufferSize, nextSpoolBlock); +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/promotionInfo.hpp Thu May 13 13:05:47 2010 -0700 @@ -0,0 +1,161 @@ +/* + * Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + */ + +// Forward declarations +class CompactibleFreeListSpace; + +class PromotedObject VALUE_OBJ_CLASS_SPEC { + private: + enum { + promoted_mask = right_n_bits(2), // i.e. 0x3 + displaced_mark = nth_bit(2), // i.e. 0x4 + next_mask = ~(right_n_bits(3)) // i.e. ~(0x7) + }; + intptr_t _next; + public: + inline PromotedObject* next() const { + return (PromotedObject*)(_next & next_mask); + } + inline void setNext(PromotedObject* x) { + assert(((intptr_t)x & ~next_mask) == 0, + "Conflict in bit usage, " + " or insufficient alignment of objects"); + _next |= (intptr_t)x; + } + inline void setPromotedMark() { + _next |= promoted_mask; + } + inline bool hasPromotedMark() const { + return (_next & promoted_mask) == promoted_mask; + } + inline void setDisplacedMark() { + _next |= displaced_mark; + } + inline bool hasDisplacedMark() const { + return (_next & displaced_mark) != 0; + } + inline void clearNext() { _next = 0; } + debug_only(void *next_addr() { return (void *) &_next; }) +}; + +class SpoolBlock: public FreeChunk { + friend class PromotionInfo; + protected: + SpoolBlock* nextSpoolBlock; + size_t bufferSize; // number of usable words in this block + markOop* displacedHdr; // the displaced headers start here + + // Note about bufferSize: it denotes the number of entries available plus 1; + // legal indices range from 1 through BufferSize - 1. See the verification + // code verify() that counts the number of displaced headers spooled. + size_t computeBufferSize() { + return (size() * sizeof(HeapWord) - sizeof(*this)) / sizeof(markOop); + } + + public: + void init() { + bufferSize = computeBufferSize(); + displacedHdr = (markOop*)&displacedHdr; + nextSpoolBlock = NULL; + } + + void print_on(outputStream* st) const; + void print() const { print_on(gclog_or_tty); } +}; + +class PromotionInfo VALUE_OBJ_CLASS_SPEC { + bool _tracking; // set if tracking + CompactibleFreeListSpace* _space; // the space to which this belongs + PromotedObject* _promoHead; // head of list of promoted objects + PromotedObject* _promoTail; // tail of list of promoted objects + SpoolBlock* _spoolHead; // first spooling block + SpoolBlock* _spoolTail; // last non-full spooling block or null + SpoolBlock* _splice_point; // when _spoolTail is null, holds list tail + SpoolBlock* _spareSpool; // free spool buffer + size_t _firstIndex; // first active index in + // first spooling block (_spoolHead) + size_t _nextIndex; // last active index + 1 in last + // spooling block (_spoolTail) + private: + // ensure that spooling space exists; return true if there is spooling space + bool ensure_spooling_space_work(); + + public: + PromotionInfo() : + _tracking(0), _space(NULL), + _promoHead(NULL), _promoTail(NULL), + _spoolHead(NULL), _spoolTail(NULL), + _spareSpool(NULL), _firstIndex(1), + _nextIndex(1) {} + + bool noPromotions() const { + assert(_promoHead != NULL || _promoTail == NULL, "list inconsistency"); + return _promoHead == NULL; + } + void startTrackingPromotions(); + void stopTrackingPromotions(uint worker_id = 0); + bool tracking() const { return _tracking; } + void track(PromotedObject* trackOop); // keep track of a promoted oop + // The following variant must be used when trackOop is not fully + // initialized and has a NULL klass: + void track(PromotedObject* trackOop, klassOop klassOfOop); // keep track of a promoted oop + void setSpace(CompactibleFreeListSpace* sp) { _space = sp; } + CompactibleFreeListSpace* space() const { return _space; } + markOop nextDisplacedHeader(); // get next header & forward spool pointer + void saveDisplacedHeader(markOop hdr); + // save header and forward spool + + inline size_t refillSize() const; + + SpoolBlock* getSpoolBlock(); // return a free spooling block + inline bool has_spooling_space() { + return _spoolTail != NULL && _spoolTail->bufferSize > _nextIndex; + } + // ensure that spooling space exists + bool ensure_spooling_space() { + return has_spooling_space() || ensure_spooling_space_work(); + } + #define PROMOTED_OOPS_ITERATE_DECL(OopClosureType, nv_suffix) \ + void promoted_oops_iterate##nv_suffix(OopClosureType* cl); + ALL_SINCE_SAVE_MARKS_CLOSURES(PROMOTED_OOPS_ITERATE_DECL) + #undef PROMOTED_OOPS_ITERATE_DECL + void promoted_oops_iterate(OopsInGenClosure* cl) { + promoted_oops_iterate_v(cl); + } + void verify() const; + void reset() { + _promoHead = NULL; + _promoTail = NULL; + _spoolHead = NULL; + _spoolTail = NULL; + _spareSpool = NULL; + _firstIndex = 0; + _nextIndex = 0; + + } + + void print_on(outputStream* st) const; + void print_statistics(uint worker_id) const; +}; +
--- a/src/share/vm/gc_implementation/concurrentMarkSweep/vmCMSOperations.cpp Wed May 12 22:06:02 2010 -0700 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/vmCMSOperations.cpp Thu May 13 13:05:47 2010 -0700 @@ -163,6 +163,7 @@ // GenCollectedHeap heap. void VM_GenCollectFullConcurrent::doit() { assert(Thread::current()->is_VM_thread(), "Should be VM thread"); + assert(GCLockerInvokesConcurrent || ExplicitGCInvokesConcurrent, "Unexpected"); GenCollectedHeap* gch = GenCollectedHeap::heap(); if (_gc_count_before == gch->total_collections()) { @@ -190,7 +191,7 @@ CMSCollector::disable_icms(); // In case CMS thread was in icms_wait(), wake it up. CMSCollector::start_icms(); - // Nudge the CMS thread to start a concurrent collection + // Nudge the CMS thread to start a concurrent collection. CMSCollector::request_full_gc(_full_gc_count_before); } else { FullGCCount_lock->notify_all(); // Inform the Java thread its work is done @@ -231,7 +232,9 @@ // e.g. at the rate of 1 full gc per ms, this could // overflow in about 1000 years. GenCollectedHeap* gch = GenCollectedHeap::heap(); - if (gch->total_full_collections_completed() <= _full_gc_count_before) { + if (_gc_cause != GCCause::_gc_locker && + gch->total_full_collections_completed() <= _full_gc_count_before) { + assert(ExplicitGCInvokesConcurrent, "Error"); // Now, wait for witnessing concurrent gc cycle to complete, // but do so in native mode, because we want to lock the // FullGCEvent_lock, which may be needed by the VM thread
--- a/src/share/vm/gc_implementation/concurrentMarkSweep/vmCMSOperations.hpp Wed May 12 22:06:02 2010 -0700 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/vmCMSOperations.hpp Thu May 13 13:05:47 2010 -0700 @@ -126,8 +126,7 @@ GCCause::Cause gc_cause) : VM_GC_Operation(gc_count_before, full_gc_count_before, true /* full */) { _gc_cause = gc_cause; - assert(FullGCCount_lock != NULL && UseConcMarkSweepGC && - ExplicitGCInvokesConcurrent, "Otherwise shouldn't be here"); + assert(FullGCCount_lock != NULL, "Error"); assert(UseAsyncConcMarkSweepGC, "Else will hang caller"); } ~VM_GenCollectFullConcurrent() {}
--- a/src/share/vm/gc_implementation/includeDB_gc_concurrentMarkSweep Wed May 12 22:06:02 2010 -0700 +++ b/src/share/vm/gc_implementation/includeDB_gc_concurrentMarkSweep Thu May 13 13:05:47 2010 -0700 @@ -122,6 +122,7 @@ compactibleFreeListSpace.hpp binaryTreeDictionary.hpp compactibleFreeListSpace.hpp freeList.hpp +compactibleFreeListSpace.hpp promotionInfo.hpp compactibleFreeListSpace.hpp space.hpp compactingPermGenGen.cpp concurrentMarkSweepGeneration.inline.hpp @@ -225,6 +226,14 @@ freeList.hpp allocationStats.hpp +promotionInfo.cpp compactibleFreeListSpace.hpp +promotionInfo.cpp markOop.inline.hpp +promotionInfo.cpp oop.inline.hpp +promotionInfo.cpp promotionInfo.hpp + +promotionInfo.hpp allocation.hpp +promotionInfo.hpp freeChunk.hpp + vmCMSOperations.cpp concurrentMarkSweepGeneration.inline.hpp vmCMSOperations.cpp concurrentMarkSweepThread.hpp vmCMSOperations.cpp dtrace.hpp
--- a/src/share/vm/memory/blockOffsetTable.hpp Wed May 12 22:06:02 2010 -0700 +++ b/src/share/vm/memory/blockOffsetTable.hpp Thu May 13 13:05:47 2010 -0700 @@ -140,14 +140,38 @@ "right address out of range"); assert(left < right, "Heap addresses out of order"); size_t num_cards = pointer_delta(right, left) >> LogN_words; - memset(&_offset_array[index_for(left)], offset, num_cards); + + // Below, we may use an explicit loop instead of memset() + // because on certain platforms memset() can give concurrent + // readers "out-of-thin-air," phantom zeros; see 6948537. + if (UseMemSetInBOT) { + memset(&_offset_array[index_for(left)], offset, num_cards); + } else { + size_t i = index_for(left); + const size_t end = i + num_cards; + for (; i < end; i++) { + _offset_array[i] = offset; + } + } } void set_offset_array(size_t left, size_t right, u_char offset) { assert(right < _vs.committed_size(), "right address out of range"); assert(left <= right, "indexes out of order"); size_t num_cards = right - left + 1; - memset(&_offset_array[left], offset, num_cards); + + // Below, we may use an explicit loop instead of memset + // because on certain platforms memset() can give concurrent + // readers "out-of-thin-air," phantom zeros; see 6948537. + if (UseMemSetInBOT) { + memset(&_offset_array[left], offset, num_cards); + } else { + size_t i = left; + const size_t end = i + num_cards; + for (; i < end; i++) { + _offset_array[i] = offset; + } + } } void check_offset_array(size_t index, HeapWord* high, HeapWord* low) const {
--- a/src/share/vm/memory/genCollectedHeap.cpp Wed May 12 22:06:02 2010 -0700 +++ b/src/share/vm/memory/genCollectedHeap.cpp Thu May 13 13:05:47 2010 -0700 @@ -410,9 +410,9 @@ } bool GenCollectedHeap::should_do_concurrent_full_gc(GCCause::Cause cause) { - return (cause == GCCause::_java_lang_system_gc || - cause == GCCause::_gc_locker) && - UseConcMarkSweepGC && ExplicitGCInvokesConcurrent; + return UseConcMarkSweepGC && + ((cause == GCCause::_gc_locker && GCLockerInvokesConcurrent) || + (cause == GCCause::_java_lang_system_gc && ExplicitGCInvokesConcurrent)); } void GenCollectedHeap::do_collection(bool full,
--- a/src/share/vm/runtime/globals.hpp Wed May 12 22:06:02 2010 -0700 +++ b/src/share/vm/runtime/globals.hpp Thu May 13 13:05:47 2010 -0700 @@ -327,6 +327,10 @@ product(bool, UseMembar, false, \ "(Unstable) Issues membars on thread state transitions") \ \ + /* Temporary: See 6948537 */ \ + experimental(bool, UseMemSetInBOT, true, \ + "(Unstable) uses memset in BOT updates in GC code") \ + \ diagnostic(bool, UnlockDiagnosticVMOptions, trueInDebug, \ "Enable normal processing of flags relating to field diagnostics")\ \ @@ -1299,6 +1303,10 @@ "also unloads classes during such a concurrent gc cycle " \ "(effective only when UseConcMarkSweepGC)") \ \ + product(bool, GCLockerInvokesConcurrent, false, \ + "The exit of a JNI CS necessitating a scavenge also" \ + " kicks off a bkgrd concurrent collection") \ + \ develop(bool, UseCMSAdaptiveFreeLists, true, \ "Use Adaptive Free Lists in the CMS generation") \ \