7127706: G1: re-enable survivors during the initial-mark pause
Summary: Re-enable survivors during the initial-mark pause. Afterwards, the concurrent marking threads have to scan them and mark everything reachable from them. The next GC will have to wait for the survivors to be scanned.
Reviewed-by: brutisso, johnc
/*
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* 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).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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*/
#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_INLINE_HPP
#define SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_INLINE_HPP
#include "gc_implementation/g1/concurrentMark.inline.hpp"
#include "gc_implementation/g1/g1CollectedHeap.hpp"
#include "gc_implementation/g1/g1OopClosures.hpp"
#include "gc_implementation/g1/g1RemSet.hpp"
/*
* This really ought to be an inline function, but apparently the C++
* compiler sometimes sees fit to ignore inline declarations. Sigh.
*/
// This must a ifdef'ed because the counting it controls is in a
// perf-critical inner loop.
#define FILTERINTOCSCLOSURE_DOHISTOGRAMCOUNT 0
template <class T>
inline void FilterIntoCSClosure::do_oop_nv(T* p) {
T heap_oop = oopDesc::load_heap_oop(p);
if (!oopDesc::is_null(heap_oop) &&
_g1->obj_in_cs(oopDesc::decode_heap_oop_not_null(heap_oop))) {
_oc->do_oop(p);
#if FILTERINTOCSCLOSURE_DOHISTOGRAMCOUNT
if (_dcto_cl != NULL)
_dcto_cl->incr_count();
#endif
}
}
#define FILTEROUTOFREGIONCLOSURE_DOHISTOGRAMCOUNT 0
template <class T>
inline void FilterOutOfRegionClosure::do_oop_nv(T* p) {
T heap_oop = oopDesc::load_heap_oop(p);
if (!oopDesc::is_null(heap_oop)) {
HeapWord* obj_hw = (HeapWord*)oopDesc::decode_heap_oop_not_null(heap_oop);
if (obj_hw < _r_bottom || obj_hw >= _r_end) {
_oc->do_oop(p);
#if FILTEROUTOFREGIONCLOSURE_DOHISTOGRAMCOUNT
_out_of_region++;
#endif
}
}
}
// This closure is applied to the fields of the objects that have just been copied.
template <class T>
inline void G1ParScanClosure::do_oop_nv(T* p) {
T heap_oop = oopDesc::load_heap_oop(p);
if (!oopDesc::is_null(heap_oop)) {
oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
if (_g1->in_cset_fast_test(obj)) {
// We're not going to even bother checking whether the object is
// already forwarded or not, as this usually causes an immediate
// stall. We'll try to prefetch the object (for write, given that
// we might need to install the forwarding reference) and we'll
// get back to it when pop it from the queue
Prefetch::write(obj->mark_addr(), 0);
Prefetch::read(obj->mark_addr(), (HeapWordSize*2));
// slightly paranoid test; I'm trying to catch potential
// problems before we go into push_on_queue to know where the
// problem is coming from
assert((obj == oopDesc::load_decode_heap_oop(p)) ||
(obj->is_forwarded() &&
obj->forwardee() == oopDesc::load_decode_heap_oop(p)),
"p should still be pointing to obj or to its forwardee");
_par_scan_state->push_on_queue(p);
} else {
_par_scan_state->update_rs(_from, p, _par_scan_state->queue_num());
}
}
}
template <class T>
inline void G1ParPushHeapRSClosure::do_oop_nv(T* p) {
T heap_oop = oopDesc::load_heap_oop(p);
if (!oopDesc::is_null(heap_oop)) {
oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
if (_g1->in_cset_fast_test(obj)) {
Prefetch::write(obj->mark_addr(), 0);
Prefetch::read(obj->mark_addr(), (HeapWordSize*2));
// Place on the references queue
_par_scan_state->push_on_queue(p);
}
}
}
template <class T>
inline void G1CMOopClosure::do_oop_nv(T* p) {
assert(_g1h->is_in_g1_reserved((HeapWord*) p), "invariant");
assert(!_g1h->is_on_master_free_list(
_g1h->heap_region_containing((HeapWord*) p)), "invariant");
oop obj = oopDesc::load_decode_heap_oop(p);
if (_cm->verbose_high()) {
gclog_or_tty->print_cr("[%d] we're looking at location "
"*"PTR_FORMAT" = "PTR_FORMAT,
_task->task_id(), p, (void*) obj);
}
_task->deal_with_reference(obj);
}
template <class T>
inline void G1RootRegionScanClosure::do_oop_nv(T* p) {
T heap_oop = oopDesc::load_heap_oop(p);
if (!oopDesc::is_null(heap_oop)) {
oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
HeapRegion* hr = _g1h->heap_region_containing((HeapWord*) obj);
if (hr != NULL) {
_cm->grayRoot(obj, obj->size(), _worker_id, hr);
}
}
}
#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_INLINE_HPP