/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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*
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* 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.
*
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#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_BUFFERINGOOPCLOSURE_HPP
#define SHARE_VM_GC_IMPLEMENTATION_G1_BUFFERINGOOPCLOSURE_HPP
#include "memory/genOopClosures.hpp"
#include "memory/generation.hpp"
#include "runtime/os.hpp"
#include "utilities/taskqueue.hpp"
// A BufferingOops closure tries to separate out the cost of finding roots
// from the cost of applying closures to them. It maintains an array of
// ref-containing locations. Until the array is full, applying the closure
// to an oop* merely records that location in the array. Since this
// closure app cost is small, an elapsed timer can approximately attribute
// all of this cost to the cost of finding the roots. When the array fills
// up, the wrapped closure is applied to all elements, keeping track of
// this elapsed time of this process, and leaving the array empty.
// The caller must be sure to call "done" to process any unprocessed
// buffered entriess.
class Generation;
class HeapRegion;
class BufferingOopClosure: public OopClosure {
protected:
enum PrivateConstants {
BufferLength = 1024
};
StarTask _buffer[BufferLength];
StarTask* _buffer_top;
StarTask* _buffer_curr;
OopClosure* _oc;
double _closure_app_seconds;
void process_buffer () {
double start = os::elapsedTime();
for (StarTask* curr = _buffer; curr < _buffer_curr; ++curr) {
if (curr->is_narrow()) {
assert(UseCompressedOops, "Error");
_oc->do_oop((narrowOop*)(*curr));
} else {
_oc->do_oop((oop*)(*curr));
}
}
_buffer_curr = _buffer;
_closure_app_seconds += (os::elapsedTime() - start);
}
template <class T> inline void do_oop_work(T* p) {
if (_buffer_curr == _buffer_top) {
process_buffer();
}
StarTask new_ref(p);
*_buffer_curr = new_ref;
++_buffer_curr;
}
public:
virtual void do_oop(narrowOop* p) { do_oop_work(p); }
virtual void do_oop(oop* p) { do_oop_work(p); }
void done () {
if (_buffer_curr > _buffer) {
process_buffer();
}
}
double closure_app_seconds () {
return _closure_app_seconds;
}
BufferingOopClosure (OopClosure *oc) :
_oc(oc),
_buffer_curr(_buffer), _buffer_top(_buffer + BufferLength),
_closure_app_seconds(0.0) { }
};
class BufferingOopsInGenClosure: public OopsInGenClosure {
BufferingOopClosure _boc;
OopsInGenClosure* _oc;
protected:
template <class T> inline void do_oop_work(T* p) {
assert(generation()->is_in_reserved((void*)p), "Must be in!");
_boc.do_oop(p);
}
public:
BufferingOopsInGenClosure(OopsInGenClosure *oc) :
_boc(oc), _oc(oc) {}
virtual void do_oop(narrowOop* p) { do_oop_work(p); }
virtual void do_oop(oop* p) { do_oop_work(p); }
void done() {
_boc.done();
}
double closure_app_seconds () {
return _boc.closure_app_seconds();
}
void set_generation(Generation* gen) {
OopsInGenClosure::set_generation(gen);
_oc->set_generation(gen);
}
void reset_generation() {
// Make sure we finish the current work with the current generation.
_boc.done();
OopsInGenClosure::reset_generation();
_oc->reset_generation();
}
};
class BufferingOopsInHeapRegionClosure: public OopsInHeapRegionClosure {
private:
enum PrivateConstants {
BufferLength = 1024
};
StarTask _buffer[BufferLength];
StarTask* _buffer_top;
StarTask* _buffer_curr;
HeapRegion* _hr_buffer[BufferLength];
HeapRegion** _hr_curr;
OopsInHeapRegionClosure* _oc;
double _closure_app_seconds;
void process_buffer () {
assert((_hr_curr - _hr_buffer) == (_buffer_curr - _buffer),
"the two lengths should be the same");
double start = os::elapsedTime();
HeapRegion** hr_curr = _hr_buffer;
HeapRegion* hr_prev = NULL;
for (StarTask* curr = _buffer; curr < _buffer_curr; ++curr) {
HeapRegion* region = *hr_curr;
if (region != hr_prev) {
_oc->set_region(region);
hr_prev = region;
}
if (curr->is_narrow()) {
assert(UseCompressedOops, "Error");
_oc->do_oop((narrowOop*)(*curr));
} else {
_oc->do_oop((oop*)(*curr));
}
++hr_curr;
}
_buffer_curr = _buffer;
_hr_curr = _hr_buffer;
_closure_app_seconds += (os::elapsedTime() - start);
}
public:
virtual void do_oop(narrowOop* p) { do_oop_work(p); }
virtual void do_oop( oop* p) { do_oop_work(p); }
template <class T> void do_oop_work(T* p) {
if (_buffer_curr == _buffer_top) {
assert(_hr_curr > _hr_buffer, "_hr_curr should be consistent with _buffer_curr");
process_buffer();
}
StarTask new_ref(p);
*_buffer_curr = new_ref;
++_buffer_curr;
*_hr_curr = _from;
++_hr_curr;
}
void done () {
if (_buffer_curr > _buffer) {
assert(_hr_curr > _hr_buffer, "_hr_curr should be consistent with _buffer_curr");
process_buffer();
}
}
double closure_app_seconds () {
return _closure_app_seconds;
}
BufferingOopsInHeapRegionClosure (OopsInHeapRegionClosure *oc) :
_oc(oc),
_buffer_curr(_buffer), _buffer_top(_buffer + BufferLength),
_hr_curr(_hr_buffer),
_closure_app_seconds(0.0) { }
};
#endif // SHARE_VM_GC_IMPLEMENTATION_G1_BUFFERINGOOPCLOSURE_HPP