Bengt Rutisson c88e3def4d 8034079: G1: Refactor the HeapRegionSet hierarchy
Reviewed-by: tschatzl, pliden
2014-03-14 10:15:46 +01:00

275 lines
8.9 KiB
C++

/*
* Copyright (c) 2011, 2012, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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#include "precompiled.hpp"
#include "gc_implementation/g1/heapRegionRemSet.hpp"
#include "gc_implementation/g1/heapRegionSet.inline.hpp"
uint FreeRegionList::_unrealistically_long_length = 0;
void HeapRegionSetBase::fill_in_ext_msg(hrs_ext_msg* msg, const char* message) {
msg->append("[%s] %s ln: %u cy: "SIZE_FORMAT,
name(), message, length(), total_capacity_bytes());
fill_in_ext_msg_extra(msg);
}
#ifndef PRODUCT
void HeapRegionSetBase::verify_region(HeapRegion* hr) {
assert(hr->containing_set() == this, err_msg("Inconsistent containing set for %u", hr->hrs_index()));
assert(!hr->is_young(), err_msg("Adding young region %u", hr->hrs_index())); // currently we don't use these sets for young regions
assert(hr->isHumongous() == regions_humongous(), err_msg("Wrong humongous state for region %u and set %s", hr->hrs_index(), name()));
assert(hr->is_empty() == regions_empty(), err_msg("Wrong empty state for region %u and set %s", hr->hrs_index(), name()));
assert(hr->rem_set()->verify_ready_for_par_iteration(), err_msg("Wrong iteration state %u", hr->hrs_index()));
}
#endif
void HeapRegionSetBase::verify() {
// It's important that we also observe the MT safety protocol even
// for the verification calls. If we do verification without the
// appropriate locks and the set changes underneath our feet
// verification might fail and send us on a wild goose chase.
check_mt_safety();
guarantee(( is_empty() && length() == 0 && total_capacity_bytes() == 0) ||
(!is_empty() && length() >= 0 && total_capacity_bytes() >= 0),
hrs_ext_msg(this, "invariant"));
}
void HeapRegionSetBase::verify_start() {
// See comment in verify() about MT safety and verification.
check_mt_safety();
assert(!_verify_in_progress,
hrs_ext_msg(this, "verification should not be in progress"));
// Do the basic verification first before we do the checks over the regions.
HeapRegionSetBase::verify();
_verify_in_progress = true;
}
void HeapRegionSetBase::verify_end() {
// See comment in verify() about MT safety and verification.
check_mt_safety();
assert(_verify_in_progress,
hrs_ext_msg(this, "verification should be in progress"));
_verify_in_progress = false;
}
void HeapRegionSetBase::print_on(outputStream* out, bool print_contents) {
out->cr();
out->print_cr("Set: %s ("PTR_FORMAT")", name(), this);
out->print_cr(" Region Assumptions");
out->print_cr(" humongous : %s", BOOL_TO_STR(regions_humongous()));
out->print_cr(" empty : %s", BOOL_TO_STR(regions_empty()));
out->print_cr(" Attributes");
out->print_cr(" length : %14u", length());
out->print_cr(" total capacity : "SIZE_FORMAT_W(14)" bytes",
total_capacity_bytes());
}
HeapRegionSetBase::HeapRegionSetBase(const char* name, bool humongous, bool empty, HRSMtSafeChecker* mt_safety_checker)
: _name(name), _verify_in_progress(false),
_is_humongous(humongous), _is_empty(empty), _mt_safety_checker(mt_safety_checker),
_count()
{ }
void FreeRegionList::set_unrealistically_long_length(uint len) {
guarantee(_unrealistically_long_length == 0, "should only be set once");
_unrealistically_long_length = len;
}
void FreeRegionList::fill_in_ext_msg_extra(hrs_ext_msg* msg) {
msg->append(" hd: "PTR_FORMAT" tl: "PTR_FORMAT, head(), tail());
}
void FreeRegionList::add_as_head_or_tail(FreeRegionList* from_list, bool as_head) {
check_mt_safety();
from_list->check_mt_safety();
verify_optional();
from_list->verify_optional();
if (from_list->is_empty()) {
return;
}
#ifdef ASSERT
FreeRegionListIterator iter(from_list);
while (iter.more_available()) {
HeapRegion* hr = iter.get_next();
// In set_containing_set() we check that we either set the value
// from NULL to non-NULL or vice versa to catch bugs. So, we have
// to NULL it first before setting it to the value.
hr->set_containing_set(NULL);
hr->set_containing_set(this);
}
#endif // ASSERT
if (_head == NULL) {
assert(length() == 0 && _tail == NULL, hrs_ext_msg(this, "invariant"));
_head = from_list->_head;
_tail = from_list->_tail;
} else {
assert(length() > 0 && _tail != NULL, hrs_ext_msg(this, "invariant"));
if (as_head) {
from_list->_tail->set_next(_head);
_head = from_list->_head;
} else {
_tail->set_next(from_list->_head);
_tail = from_list->_tail;
}
}
_count.increment(from_list->length(), from_list->total_capacity_bytes());
from_list->clear();
verify_optional();
from_list->verify_optional();
}
void FreeRegionList::add_as_head(FreeRegionList* from_list) {
add_as_head_or_tail(from_list, true /* as_head */);
}
void FreeRegionList::add_as_tail(FreeRegionList* from_list) {
add_as_head_or_tail(from_list, false /* as_head */);
}
void FreeRegionList::remove_all() {
check_mt_safety();
verify_optional();
HeapRegion* curr = _head;
while (curr != NULL) {
verify_region(curr);
HeapRegion* next = curr->next();
curr->set_next(NULL);
curr->set_containing_set(NULL);
curr = next;
}
clear();
verify_optional();
}
void FreeRegionList::remove_all_pending(uint target_count) {
check_mt_safety();
assert(target_count > 1, hrs_ext_msg(this, "pre-condition"));
assert(!is_empty(), hrs_ext_msg(this, "pre-condition"));
verify_optional();
DEBUG_ONLY(uint old_length = length();)
HeapRegion* curr = _head;
HeapRegion* prev = NULL;
uint count = 0;
while (curr != NULL) {
verify_region(curr);
HeapRegion* next = curr->next();
if (curr->pending_removal()) {
assert(count < target_count,
hrs_err_msg("[%s] should not come across more regions "
"pending for removal than target_count: %u",
name(), target_count));
if (prev == NULL) {
assert(_head == curr, hrs_ext_msg(this, "invariant"));
_head = next;
} else {
assert(_head != curr, hrs_ext_msg(this, "invariant"));
prev->set_next(next);
}
if (next == NULL) {
assert(_tail == curr, hrs_ext_msg(this, "invariant"));
_tail = prev;
} else {
assert(_tail != curr, hrs_ext_msg(this, "invariant"));
}
curr->set_next(NULL);
remove(curr);
curr->set_pending_removal(false);
count += 1;
// If we have come across the target number of regions we can
// just bail out. However, for debugging purposes, we can just
// carry on iterating to make sure there are not more regions
// tagged with pending removal.
DEBUG_ONLY(if (count == target_count) break;)
} else {
prev = curr;
}
curr = next;
}
assert(count == target_count,
hrs_err_msg("[%s] count: %u should be == target_count: %u",
name(), count, target_count));
assert(length() + target_count == old_length,
hrs_err_msg("[%s] new length should be consistent "
"new length: %u old length: %u target_count: %u",
name(), length(), old_length, target_count));
verify_optional();
}
void FreeRegionList::verify() {
// See comment in HeapRegionSetBase::verify() about MT safety and
// verification.
check_mt_safety();
// This will also do the basic verification too.
verify_start();
verify_list();
verify_end();
}
void FreeRegionList::clear() {
_count = HeapRegionSetCount();
_head = NULL;
_tail = NULL;
}
void FreeRegionList::print_on(outputStream* out, bool print_contents) {
HeapRegionSetBase::print_on(out, print_contents);
out->print_cr(" Linking");
out->print_cr(" head : "PTR_FORMAT, _head);
out->print_cr(" tail : "PTR_FORMAT, _tail);
if (print_contents) {
out->print_cr(" Contents");
FreeRegionListIterator iter(this);
while (iter.more_available()) {
HeapRegion* hr = iter.get_next();
hr->print_on(out);
}
}
}