8025852: Remove unnecessary setters in collector policy classes
Summary: Use instance variables directly within the collector policy classes and remove unused setters.
Reviewed-by: tschatzl, jcoomes
/*
* 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.
*
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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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*/
#include "precompiled.hpp"
#include "gc_implementation/g1/g1AllocRegion.inline.hpp"
#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
G1CollectedHeap* G1AllocRegion::_g1h = NULL;
HeapRegion* G1AllocRegion::_dummy_region = NULL;
void G1AllocRegion::setup(G1CollectedHeap* g1h, HeapRegion* dummy_region) {
assert(_dummy_region == NULL, "should be set once");
assert(dummy_region != NULL, "pre-condition");
assert(dummy_region->free() == 0, "pre-condition");
// Make sure that any allocation attempt on this region will fail
// and will not trigger any asserts.
assert(allocate(dummy_region, 1, false) == NULL, "should fail");
assert(par_allocate(dummy_region, 1, false) == NULL, "should fail");
assert(allocate(dummy_region, 1, true) == NULL, "should fail");
assert(par_allocate(dummy_region, 1, true) == NULL, "should fail");
_g1h = g1h;
_dummy_region = dummy_region;
}
void G1AllocRegion::fill_up_remaining_space(HeapRegion* alloc_region,
bool bot_updates) {
assert(alloc_region != NULL && alloc_region != _dummy_region,
"pre-condition");
// Other threads might still be trying to allocate using a CAS out
// of the region we are trying to retire, as they can do so without
// holding the lock. So, we first have to make sure that noone else
// can allocate out of it by doing a maximal allocation. Even if our
// CAS attempt fails a few times, we'll succeed sooner or later
// given that failed CAS attempts mean that the region is getting
// closed to being full.
size_t free_word_size = alloc_region->free() / HeapWordSize;
// This is the minimum free chunk we can turn into a dummy
// object. If the free space falls below this, then noone can
// allocate in this region anyway (all allocation requests will be
// of a size larger than this) so we won't have to perform the dummy
// allocation.
size_t min_word_size_to_fill = CollectedHeap::min_fill_size();
while (free_word_size >= min_word_size_to_fill) {
HeapWord* dummy = par_allocate(alloc_region, free_word_size, bot_updates);
if (dummy != NULL) {
// If the allocation was successful we should fill in the space.
CollectedHeap::fill_with_object(dummy, free_word_size);
alloc_region->set_pre_dummy_top(dummy);
break;
}
free_word_size = alloc_region->free() / HeapWordSize;
// It's also possible that someone else beats us to the
// allocation and they fill up the region. In that case, we can
// just get out of the loop.
}
assert(alloc_region->free() / HeapWordSize < min_word_size_to_fill,
"post-condition");
}
void G1AllocRegion::retire(bool fill_up) {
assert(_alloc_region != NULL, ar_ext_msg(this, "not initialized properly"));
trace("retiring");
HeapRegion* alloc_region = _alloc_region;
if (alloc_region != _dummy_region) {
// We never have to check whether the active region is empty or not,
// and potentially free it if it is, given that it's guaranteed that
// it will never be empty.
assert(!alloc_region->is_empty(),
ar_ext_msg(this, "the alloc region should never be empty"));
if (fill_up) {
fill_up_remaining_space(alloc_region, _bot_updates);
}
assert(alloc_region->used() >= _used_bytes_before,
ar_ext_msg(this, "invariant"));
size_t allocated_bytes = alloc_region->used() - _used_bytes_before;
retire_region(alloc_region, allocated_bytes);
_used_bytes_before = 0;
_alloc_region = _dummy_region;
}
trace("retired");
}
HeapWord* G1AllocRegion::new_alloc_region_and_allocate(size_t word_size,
bool force) {
assert(_alloc_region == _dummy_region, ar_ext_msg(this, "pre-condition"));
assert(_used_bytes_before == 0, ar_ext_msg(this, "pre-condition"));
trace("attempting region allocation");
HeapRegion* new_alloc_region = allocate_new_region(word_size, force);
if (new_alloc_region != NULL) {
new_alloc_region->reset_pre_dummy_top();
// Need to do this before the allocation
_used_bytes_before = new_alloc_region->used();
HeapWord* result = allocate(new_alloc_region, word_size, _bot_updates);
assert(result != NULL, ar_ext_msg(this, "the allocation should succeeded"));
OrderAccess::storestore();
// Note that we first perform the allocation and then we store the
// region in _alloc_region. This is the reason why an active region
// can never be empty.
_alloc_region = new_alloc_region;
_count += 1;
trace("region allocation successful");
return result;
} else {
trace("region allocation failed");
return NULL;
}
ShouldNotReachHere();
}
void G1AllocRegion::fill_in_ext_msg(ar_ext_msg* msg, const char* message) {
msg->append("[%s] %s c: %u b: %s r: "PTR_FORMAT" u: "SIZE_FORMAT,
_name, message, _count, BOOL_TO_STR(_bot_updates),
_alloc_region, _used_bytes_before);
}
void G1AllocRegion::init() {
trace("initializing");
assert(_alloc_region == NULL && _used_bytes_before == 0,
ar_ext_msg(this, "pre-condition"));
assert(_dummy_region != NULL, ar_ext_msg(this, "should have been set"));
_alloc_region = _dummy_region;
_count = 0;
trace("initialized");
}
void G1AllocRegion::set(HeapRegion* alloc_region) {
trace("setting");
// We explicitly check that the region is not empty to make sure we
// maintain the "the alloc region cannot be empty" invariant.
assert(alloc_region != NULL && !alloc_region->is_empty(),
ar_ext_msg(this, "pre-condition"));
assert(_alloc_region == _dummy_region &&
_used_bytes_before == 0 && _count == 0,
ar_ext_msg(this, "pre-condition"));
_used_bytes_before = alloc_region->used();
_alloc_region = alloc_region;
_count += 1;
trace("set");
}
HeapRegion* G1AllocRegion::release() {
trace("releasing");
HeapRegion* alloc_region = _alloc_region;
retire(false /* fill_up */);
assert(_alloc_region == _dummy_region,
ar_ext_msg(this, "post-condition of retire()"));
_alloc_region = NULL;
trace("released");
return (alloc_region == _dummy_region) ? NULL : alloc_region;
}
#if G1_ALLOC_REGION_TRACING
void G1AllocRegion::trace(const char* str, size_t word_size, HeapWord* result) {
// All the calls to trace that set either just the size or the size
// and the result are considered part of level 2 tracing and are
// skipped during level 1 tracing.
if ((word_size == 0 && result == NULL) || (G1_ALLOC_REGION_TRACING > 1)) {
const size_t buffer_length = 128;
char hr_buffer[buffer_length];
char rest_buffer[buffer_length];
HeapRegion* alloc_region = _alloc_region;
if (alloc_region == NULL) {
jio_snprintf(hr_buffer, buffer_length, "NULL");
} else if (alloc_region == _dummy_region) {
jio_snprintf(hr_buffer, buffer_length, "DUMMY");
} else {
jio_snprintf(hr_buffer, buffer_length,
HR_FORMAT, HR_FORMAT_PARAMS(alloc_region));
}
if (G1_ALLOC_REGION_TRACING > 1) {
if (result != NULL) {
jio_snprintf(rest_buffer, buffer_length, SIZE_FORMAT" "PTR_FORMAT,
word_size, result);
} else if (word_size != 0) {
jio_snprintf(rest_buffer, buffer_length, SIZE_FORMAT, word_size);
} else {
jio_snprintf(rest_buffer, buffer_length, "");
}
} else {
jio_snprintf(rest_buffer, buffer_length, "");
}
tty->print_cr("[%s] %u %s : %s %s",
_name, _count, hr_buffer, str, rest_buffer);
}
}
#endif // G1_ALLOC_REGION_TRACING
G1AllocRegion::G1AllocRegion(const char* name,
bool bot_updates)
: _name(name), _bot_updates(bot_updates),
_alloc_region(NULL), _count(0), _used_bytes_before(0) { }