--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/parallel/mutableNUMASpace.cpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,1000 @@
+/*
+ * Copyright (c) 2006, 2016, 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
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc/parallel/mutableNUMASpace.hpp"
+#include "gc/shared/collectedHeap.hpp"
+#include "gc/shared/spaceDecorator.hpp"
+#include "oops/oop.inline.hpp"
+#include "runtime/atomic.hpp"
+#include "runtime/thread.inline.hpp"
+#include "utilities/align.hpp"
+
+MutableNUMASpace::MutableNUMASpace(size_t alignment) : MutableSpace(alignment), _must_use_large_pages(false) {
+ _lgrp_spaces = new (ResourceObj::C_HEAP, mtGC) GrowableArray<LGRPSpace*>(0, true);
+ _page_size = os::vm_page_size();
+ _adaptation_cycles = 0;
+ _samples_count = 0;
+
+#ifdef LINUX
+ // Changing the page size can lead to freeing of memory. When using large pages
+ // and the memory has been both reserved and committed, Linux does not support
+ // freeing parts of it.
+ if (UseLargePages && !os::can_commit_large_page_memory()) {
+ _must_use_large_pages = true;
+ }
+#endif // LINUX
+
+ update_layout(true);
+}
+
+MutableNUMASpace::~MutableNUMASpace() {
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ delete lgrp_spaces()->at(i);
+ }
+ delete lgrp_spaces();
+}
+
+#ifndef PRODUCT
+void MutableNUMASpace::mangle_unused_area() {
+ // This method should do nothing.
+ // It can be called on a numa space during a full compaction.
+}
+void MutableNUMASpace::mangle_unused_area_complete() {
+ // This method should do nothing.
+ // It can be called on a numa space during a full compaction.
+}
+void MutableNUMASpace::mangle_region(MemRegion mr) {
+ // This method should do nothing because numa spaces are not mangled.
+}
+void MutableNUMASpace::set_top_for_allocations(HeapWord* v) {
+ assert(false, "Do not mangle MutableNUMASpace's");
+}
+void MutableNUMASpace::set_top_for_allocations() {
+ // This method should do nothing.
+}
+void MutableNUMASpace::check_mangled_unused_area(HeapWord* limit) {
+ // This method should do nothing.
+}
+void MutableNUMASpace::check_mangled_unused_area_complete() {
+ // This method should do nothing.
+}
+#endif // NOT_PRODUCT
+
+// There may be unallocated holes in the middle chunks
+// that should be filled with dead objects to ensure parsability.
+void MutableNUMASpace::ensure_parsability() {
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ LGRPSpace *ls = lgrp_spaces()->at(i);
+ MutableSpace *s = ls->space();
+ if (s->top() < top()) { // For all spaces preceding the one containing top()
+ if (s->free_in_words() > 0) {
+ intptr_t cur_top = (intptr_t)s->top();
+ size_t words_left_to_fill = pointer_delta(s->end(), s->top());;
+ while (words_left_to_fill > 0) {
+ size_t words_to_fill = MIN2(words_left_to_fill, CollectedHeap::filler_array_max_size());
+ assert(words_to_fill >= CollectedHeap::min_fill_size(),
+ "Remaining size (" SIZE_FORMAT ") is too small to fill (based on " SIZE_FORMAT " and " SIZE_FORMAT ")",
+ words_to_fill, words_left_to_fill, CollectedHeap::filler_array_max_size());
+ CollectedHeap::fill_with_object((HeapWord*)cur_top, words_to_fill);
+ if (!os::numa_has_static_binding()) {
+ size_t touched_words = words_to_fill;
+#ifndef ASSERT
+ if (!ZapUnusedHeapArea) {
+ touched_words = MIN2((size_t)align_object_size(typeArrayOopDesc::header_size(T_INT)),
+ touched_words);
+ }
+#endif
+ MemRegion invalid;
+ HeapWord *crossing_start = align_up((HeapWord*)cur_top, os::vm_page_size());
+ HeapWord *crossing_end = align_down((HeapWord*)(cur_top + touched_words), os::vm_page_size());
+ if (crossing_start != crossing_end) {
+ // If object header crossed a small page boundary we mark the area
+ // as invalid rounding it to a page_size().
+ HeapWord *start = MAX2(align_down((HeapWord*)cur_top, page_size()), s->bottom());
+ HeapWord *end = MIN2(align_up((HeapWord*)(cur_top + touched_words), page_size()), s->end());
+ invalid = MemRegion(start, end);
+ }
+
+ ls->add_invalid_region(invalid);
+ }
+ cur_top = cur_top + (words_to_fill * HeapWordSize);
+ words_left_to_fill -= words_to_fill;
+ }
+ }
+ } else {
+ if (!os::numa_has_static_binding()) {
+#ifdef ASSERT
+ MemRegion invalid(s->top(), s->end());
+ ls->add_invalid_region(invalid);
+#else
+ if (ZapUnusedHeapArea) {
+ MemRegion invalid(s->top(), s->end());
+ ls->add_invalid_region(invalid);
+ } else {
+ return;
+ }
+#endif
+ } else {
+ return;
+ }
+ }
+ }
+}
+
+size_t MutableNUMASpace::used_in_words() const {
+ size_t s = 0;
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ s += lgrp_spaces()->at(i)->space()->used_in_words();
+ }
+ return s;
+}
+
+size_t MutableNUMASpace::free_in_words() const {
+ size_t s = 0;
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ s += lgrp_spaces()->at(i)->space()->free_in_words();
+ }
+ return s;
+}
+
+
+size_t MutableNUMASpace::tlab_capacity(Thread *thr) const {
+ guarantee(thr != NULL, "No thread");
+ int lgrp_id = thr->lgrp_id();
+ if (lgrp_id == -1) {
+ // This case can occur after the topology of the system has
+ // changed. Thread can change their location, the new home
+ // group will be determined during the first allocation
+ // attempt. For now we can safely assume that all spaces
+ // have equal size because the whole space will be reinitialized.
+ if (lgrp_spaces()->length() > 0) {
+ return capacity_in_bytes() / lgrp_spaces()->length();
+ } else {
+ assert(false, "There should be at least one locality group");
+ return 0;
+ }
+ }
+ // That's the normal case, where we know the locality group of the thread.
+ int i = lgrp_spaces()->find(&lgrp_id, LGRPSpace::equals);
+ if (i == -1) {
+ return 0;
+ }
+ return lgrp_spaces()->at(i)->space()->capacity_in_bytes();
+}
+
+size_t MutableNUMASpace::tlab_used(Thread *thr) const {
+ // Please see the comments for tlab_capacity().
+ guarantee(thr != NULL, "No thread");
+ int lgrp_id = thr->lgrp_id();
+ if (lgrp_id == -1) {
+ if (lgrp_spaces()->length() > 0) {
+ return (used_in_bytes()) / lgrp_spaces()->length();
+ } else {
+ assert(false, "There should be at least one locality group");
+ return 0;
+ }
+ }
+ int i = lgrp_spaces()->find(&lgrp_id, LGRPSpace::equals);
+ if (i == -1) {
+ return 0;
+ }
+ return lgrp_spaces()->at(i)->space()->used_in_bytes();
+}
+
+
+size_t MutableNUMASpace::unsafe_max_tlab_alloc(Thread *thr) const {
+ // Please see the comments for tlab_capacity().
+ guarantee(thr != NULL, "No thread");
+ int lgrp_id = thr->lgrp_id();
+ if (lgrp_id == -1) {
+ if (lgrp_spaces()->length() > 0) {
+ return free_in_bytes() / lgrp_spaces()->length();
+ } else {
+ assert(false, "There should be at least one locality group");
+ return 0;
+ }
+ }
+ int i = lgrp_spaces()->find(&lgrp_id, LGRPSpace::equals);
+ if (i == -1) {
+ return 0;
+ }
+ return lgrp_spaces()->at(i)->space()->free_in_bytes();
+}
+
+
+size_t MutableNUMASpace::capacity_in_words(Thread* thr) const {
+ guarantee(thr != NULL, "No thread");
+ int lgrp_id = thr->lgrp_id();
+ if (lgrp_id == -1) {
+ if (lgrp_spaces()->length() > 0) {
+ return capacity_in_words() / lgrp_spaces()->length();
+ } else {
+ assert(false, "There should be at least one locality group");
+ return 0;
+ }
+ }
+ int i = lgrp_spaces()->find(&lgrp_id, LGRPSpace::equals);
+ if (i == -1) {
+ return 0;
+ }
+ return lgrp_spaces()->at(i)->space()->capacity_in_words();
+}
+
+// Check if the NUMA topology has changed. Add and remove spaces if needed.
+// The update can be forced by setting the force parameter equal to true.
+bool MutableNUMASpace::update_layout(bool force) {
+ // Check if the topology had changed.
+ bool changed = os::numa_topology_changed();
+ if (force || changed) {
+ // Compute lgrp intersection. Add/remove spaces.
+ int lgrp_limit = (int)os::numa_get_groups_num();
+ int *lgrp_ids = NEW_C_HEAP_ARRAY(int, lgrp_limit, mtGC);
+ int lgrp_num = (int)os::numa_get_leaf_groups(lgrp_ids, lgrp_limit);
+ assert(lgrp_num > 0, "There should be at least one locality group");
+ // Add new spaces for the new nodes
+ for (int i = 0; i < lgrp_num; i++) {
+ bool found = false;
+ for (int j = 0; j < lgrp_spaces()->length(); j++) {
+ if (lgrp_spaces()->at(j)->lgrp_id() == lgrp_ids[i]) {
+ found = true;
+ break;
+ }
+ }
+ if (!found) {
+ lgrp_spaces()->append(new LGRPSpace(lgrp_ids[i], alignment()));
+ }
+ }
+
+ // Remove spaces for the removed nodes.
+ for (int i = 0; i < lgrp_spaces()->length();) {
+ bool found = false;
+ for (int j = 0; j < lgrp_num; j++) {
+ if (lgrp_spaces()->at(i)->lgrp_id() == lgrp_ids[j]) {
+ found = true;
+ break;
+ }
+ }
+ if (!found) {
+ delete lgrp_spaces()->at(i);
+ lgrp_spaces()->remove_at(i);
+ } else {
+ i++;
+ }
+ }
+
+ FREE_C_HEAP_ARRAY(int, lgrp_ids);
+
+ if (changed) {
+ for (JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
+ thread->set_lgrp_id(-1);
+ }
+ }
+ return true;
+ }
+ return false;
+}
+
+// Bias region towards the first-touching lgrp. Set the right page sizes.
+void MutableNUMASpace::bias_region(MemRegion mr, int lgrp_id) {
+ HeapWord *start = align_up(mr.start(), page_size());
+ HeapWord *end = align_down(mr.end(), page_size());
+ if (end > start) {
+ MemRegion aligned_region(start, end);
+ assert((intptr_t)aligned_region.start() % page_size() == 0 &&
+ (intptr_t)aligned_region.byte_size() % page_size() == 0, "Bad alignment");
+ assert(region().contains(aligned_region), "Sanity");
+ // First we tell the OS which page size we want in the given range. The underlying
+ // large page can be broken down if we require small pages.
+ os::realign_memory((char*)aligned_region.start(), aligned_region.byte_size(), page_size());
+ // Then we uncommit the pages in the range.
+ os::free_memory((char*)aligned_region.start(), aligned_region.byte_size(), page_size());
+ // And make them local/first-touch biased.
+ os::numa_make_local((char*)aligned_region.start(), aligned_region.byte_size(), lgrp_id);
+ }
+}
+
+// Free all pages in the region.
+void MutableNUMASpace::free_region(MemRegion mr) {
+ HeapWord *start = align_up(mr.start(), page_size());
+ HeapWord *end = align_down(mr.end(), page_size());
+ if (end > start) {
+ MemRegion aligned_region(start, end);
+ assert((intptr_t)aligned_region.start() % page_size() == 0 &&
+ (intptr_t)aligned_region.byte_size() % page_size() == 0, "Bad alignment");
+ assert(region().contains(aligned_region), "Sanity");
+ os::free_memory((char*)aligned_region.start(), aligned_region.byte_size(), page_size());
+ }
+}
+
+// Update space layout. Perform adaptation.
+void MutableNUMASpace::update() {
+ if (update_layout(false)) {
+ // If the topology has changed, make all chunks zero-sized.
+ // And clear the alloc-rate statistics.
+ // In future we may want to handle this more gracefully in order
+ // to avoid the reallocation of the pages as much as possible.
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ LGRPSpace *ls = lgrp_spaces()->at(i);
+ MutableSpace *s = ls->space();
+ s->set_end(s->bottom());
+ s->set_top(s->bottom());
+ ls->clear_alloc_rate();
+ }
+ // A NUMA space is never mangled
+ initialize(region(),
+ SpaceDecorator::Clear,
+ SpaceDecorator::DontMangle);
+ } else {
+ bool should_initialize = false;
+ if (!os::numa_has_static_binding()) {
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ if (!lgrp_spaces()->at(i)->invalid_region().is_empty()) {
+ should_initialize = true;
+ break;
+ }
+ }
+ }
+
+ if (should_initialize ||
+ (UseAdaptiveNUMAChunkSizing && adaptation_cycles() < samples_count())) {
+ // A NUMA space is never mangled
+ initialize(region(),
+ SpaceDecorator::Clear,
+ SpaceDecorator::DontMangle);
+ }
+ }
+
+ if (NUMAStats) {
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ lgrp_spaces()->at(i)->accumulate_statistics(page_size());
+ }
+ }
+
+ scan_pages(NUMAPageScanRate);
+}
+
+// Scan pages. Free pages that have smaller size or wrong placement.
+void MutableNUMASpace::scan_pages(size_t page_count)
+{
+ size_t pages_per_chunk = page_count / lgrp_spaces()->length();
+ if (pages_per_chunk > 0) {
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ LGRPSpace *ls = lgrp_spaces()->at(i);
+ ls->scan_pages(page_size(), pages_per_chunk);
+ }
+ }
+}
+
+// Accumulate statistics about the allocation rate of each lgrp.
+void MutableNUMASpace::accumulate_statistics() {
+ if (UseAdaptiveNUMAChunkSizing) {
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ lgrp_spaces()->at(i)->sample();
+ }
+ increment_samples_count();
+ }
+
+ if (NUMAStats) {
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ lgrp_spaces()->at(i)->accumulate_statistics(page_size());
+ }
+ }
+}
+
+// Get the current size of a chunk.
+// This function computes the size of the chunk based on the
+// difference between chunk ends. This allows it to work correctly in
+// case the whole space is resized and during the process of adaptive
+// chunk resizing.
+size_t MutableNUMASpace::current_chunk_size(int i) {
+ HeapWord *cur_end, *prev_end;
+ if (i == 0) {
+ prev_end = bottom();
+ } else {
+ prev_end = lgrp_spaces()->at(i - 1)->space()->end();
+ }
+ if (i == lgrp_spaces()->length() - 1) {
+ cur_end = end();
+ } else {
+ cur_end = lgrp_spaces()->at(i)->space()->end();
+ }
+ if (cur_end > prev_end) {
+ return pointer_delta(cur_end, prev_end, sizeof(char));
+ }
+ return 0;
+}
+
+// Return the default chunk size by equally diving the space.
+// page_size() aligned.
+size_t MutableNUMASpace::default_chunk_size() {
+ return base_space_size() / lgrp_spaces()->length() * page_size();
+}
+
+// Produce a new chunk size. page_size() aligned.
+// This function is expected to be called on sequence of i's from 0 to
+// lgrp_spaces()->length().
+size_t MutableNUMASpace::adaptive_chunk_size(int i, size_t limit) {
+ size_t pages_available = base_space_size();
+ for (int j = 0; j < i; j++) {
+ pages_available -= align_down(current_chunk_size(j), page_size()) / page_size();
+ }
+ pages_available -= lgrp_spaces()->length() - i - 1;
+ assert(pages_available > 0, "No pages left");
+ float alloc_rate = 0;
+ for (int j = i; j < lgrp_spaces()->length(); j++) {
+ alloc_rate += lgrp_spaces()->at(j)->alloc_rate()->average();
+ }
+ size_t chunk_size = 0;
+ if (alloc_rate > 0) {
+ LGRPSpace *ls = lgrp_spaces()->at(i);
+ chunk_size = (size_t)(ls->alloc_rate()->average() / alloc_rate * pages_available) * page_size();
+ }
+ chunk_size = MAX2(chunk_size, page_size());
+
+ if (limit > 0) {
+ limit = align_down(limit, page_size());
+ if (chunk_size > current_chunk_size(i)) {
+ size_t upper_bound = pages_available * page_size();
+ if (upper_bound > limit &&
+ current_chunk_size(i) < upper_bound - limit) {
+ // The resulting upper bound should not exceed the available
+ // amount of memory (pages_available * page_size()).
+ upper_bound = current_chunk_size(i) + limit;
+ }
+ chunk_size = MIN2(chunk_size, upper_bound);
+ } else {
+ size_t lower_bound = page_size();
+ if (current_chunk_size(i) > limit) { // lower_bound shouldn't underflow.
+ lower_bound = current_chunk_size(i) - limit;
+ }
+ chunk_size = MAX2(chunk_size, lower_bound);
+ }
+ }
+ assert(chunk_size <= pages_available * page_size(), "Chunk size out of range");
+ return chunk_size;
+}
+
+
+// Return the bottom_region and the top_region. Align them to page_size() boundary.
+// |------------------new_region---------------------------------|
+// |----bottom_region--|---intersection---|------top_region------|
+void MutableNUMASpace::select_tails(MemRegion new_region, MemRegion intersection,
+ MemRegion* bottom_region, MemRegion *top_region) {
+ // Is there bottom?
+ if (new_region.start() < intersection.start()) { // Yes
+ // Try to coalesce small pages into a large one.
+ if (UseLargePages && page_size() >= alignment()) {
+ HeapWord* p = align_up(intersection.start(), alignment());
+ if (new_region.contains(p)
+ && pointer_delta(p, new_region.start(), sizeof(char)) >= alignment()) {
+ if (intersection.contains(p)) {
+ intersection = MemRegion(p, intersection.end());
+ } else {
+ intersection = MemRegion(p, p);
+ }
+ }
+ }
+ *bottom_region = MemRegion(new_region.start(), intersection.start());
+ } else {
+ *bottom_region = MemRegion();
+ }
+
+ // Is there top?
+ if (intersection.end() < new_region.end()) { // Yes
+ // Try to coalesce small pages into a large one.
+ if (UseLargePages && page_size() >= alignment()) {
+ HeapWord* p = align_down(intersection.end(), alignment());
+ if (new_region.contains(p)
+ && pointer_delta(new_region.end(), p, sizeof(char)) >= alignment()) {
+ if (intersection.contains(p)) {
+ intersection = MemRegion(intersection.start(), p);
+ } else {
+ intersection = MemRegion(p, p);
+ }
+ }
+ }
+ *top_region = MemRegion(intersection.end(), new_region.end());
+ } else {
+ *top_region = MemRegion();
+ }
+}
+
+// Try to merge the invalid region with the bottom or top region by decreasing
+// the intersection area. Return the invalid_region aligned to the page_size()
+// boundary if it's inside the intersection. Return non-empty invalid_region
+// if it lies inside the intersection (also page-aligned).
+// |------------------new_region---------------------------------|
+// |----------------|-------invalid---|--------------------------|
+// |----bottom_region--|---intersection---|------top_region------|
+void MutableNUMASpace::merge_regions(MemRegion new_region, MemRegion* intersection,
+ MemRegion *invalid_region) {
+ if (intersection->start() >= invalid_region->start() && intersection->contains(invalid_region->end())) {
+ *intersection = MemRegion(invalid_region->end(), intersection->end());
+ *invalid_region = MemRegion();
+ } else
+ if (intersection->end() <= invalid_region->end() && intersection->contains(invalid_region->start())) {
+ *intersection = MemRegion(intersection->start(), invalid_region->start());
+ *invalid_region = MemRegion();
+ } else
+ if (intersection->equals(*invalid_region) || invalid_region->contains(*intersection)) {
+ *intersection = MemRegion(new_region.start(), new_region.start());
+ *invalid_region = MemRegion();
+ } else
+ if (intersection->contains(invalid_region)) {
+ // That's the only case we have to make an additional bias_region() call.
+ HeapWord* start = invalid_region->start();
+ HeapWord* end = invalid_region->end();
+ if (UseLargePages && page_size() >= alignment()) {
+ HeapWord *p = align_down(start, alignment());
+ if (new_region.contains(p)) {
+ start = p;
+ }
+ p = align_up(end, alignment());
+ if (new_region.contains(end)) {
+ end = p;
+ }
+ }
+ if (intersection->start() > start) {
+ *intersection = MemRegion(start, intersection->end());
+ }
+ if (intersection->end() < end) {
+ *intersection = MemRegion(intersection->start(), end);
+ }
+ *invalid_region = MemRegion(start, end);
+ }
+}
+
+void MutableNUMASpace::initialize(MemRegion mr,
+ bool clear_space,
+ bool mangle_space,
+ bool setup_pages) {
+ assert(clear_space, "Reallocation will destroy data!");
+ assert(lgrp_spaces()->length() > 0, "There should be at least one space");
+
+ MemRegion old_region = region(), new_region;
+ set_bottom(mr.start());
+ set_end(mr.end());
+ // Must always clear the space
+ clear(SpaceDecorator::DontMangle);
+
+ // Compute chunk sizes
+ size_t prev_page_size = page_size();
+ set_page_size(UseLargePages ? alignment() : os::vm_page_size());
+ HeapWord* rounded_bottom = align_up(bottom(), page_size());
+ HeapWord* rounded_end = align_down(end(), page_size());
+ size_t base_space_size_pages = pointer_delta(rounded_end, rounded_bottom, sizeof(char)) / page_size();
+
+ // Try small pages if the chunk size is too small
+ if (base_space_size_pages / lgrp_spaces()->length() == 0
+ && page_size() > (size_t)os::vm_page_size()) {
+ // Changing the page size below can lead to freeing of memory. So we fail initialization.
+ if (_must_use_large_pages) {
+ vm_exit_during_initialization("Failed initializing NUMA with large pages. Too small heap size");
+ }
+ set_page_size(os::vm_page_size());
+ rounded_bottom = align_up(bottom(), page_size());
+ rounded_end = align_down(end(), page_size());
+ base_space_size_pages = pointer_delta(rounded_end, rounded_bottom, sizeof(char)) / page_size();
+ }
+ guarantee(base_space_size_pages / lgrp_spaces()->length() > 0, "Space too small");
+ set_base_space_size(base_space_size_pages);
+
+ // Handle space resize
+ MemRegion top_region, bottom_region;
+ if (!old_region.equals(region())) {
+ new_region = MemRegion(rounded_bottom, rounded_end);
+ MemRegion intersection = new_region.intersection(old_region);
+ if (intersection.start() == NULL ||
+ intersection.end() == NULL ||
+ prev_page_size > page_size()) { // If the page size got smaller we have to change
+ // the page size preference for the whole space.
+ intersection = MemRegion(new_region.start(), new_region.start());
+ }
+ select_tails(new_region, intersection, &bottom_region, &top_region);
+ bias_region(bottom_region, lgrp_spaces()->at(0)->lgrp_id());
+ bias_region(top_region, lgrp_spaces()->at(lgrp_spaces()->length() - 1)->lgrp_id());
+ }
+
+ // Check if the space layout has changed significantly?
+ // This happens when the space has been resized so that either head or tail
+ // chunk became less than a page.
+ bool layout_valid = UseAdaptiveNUMAChunkSizing &&
+ current_chunk_size(0) > page_size() &&
+ current_chunk_size(lgrp_spaces()->length() - 1) > page_size();
+
+
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ LGRPSpace *ls = lgrp_spaces()->at(i);
+ MutableSpace *s = ls->space();
+ old_region = s->region();
+
+ size_t chunk_byte_size = 0, old_chunk_byte_size = 0;
+ if (i < lgrp_spaces()->length() - 1) {
+ if (!UseAdaptiveNUMAChunkSizing ||
+ (UseAdaptiveNUMAChunkSizing && NUMAChunkResizeWeight == 0) ||
+ samples_count() < AdaptiveSizePolicyReadyThreshold) {
+ // No adaptation. Divide the space equally.
+ chunk_byte_size = default_chunk_size();
+ } else
+ if (!layout_valid || NUMASpaceResizeRate == 0) {
+ // Fast adaptation. If no space resize rate is set, resize
+ // the chunks instantly.
+ chunk_byte_size = adaptive_chunk_size(i, 0);
+ } else {
+ // Slow adaptation. Resize the chunks moving no more than
+ // NUMASpaceResizeRate bytes per collection.
+ size_t limit = NUMASpaceResizeRate /
+ (lgrp_spaces()->length() * (lgrp_spaces()->length() + 1) / 2);
+ chunk_byte_size = adaptive_chunk_size(i, MAX2(limit * (i + 1), page_size()));
+ }
+
+ assert(chunk_byte_size >= page_size(), "Chunk size too small");
+ assert(chunk_byte_size <= capacity_in_bytes(), "Sanity check");
+ }
+
+ if (i == 0) { // Bottom chunk
+ if (i != lgrp_spaces()->length() - 1) {
+ new_region = MemRegion(bottom(), rounded_bottom + (chunk_byte_size >> LogHeapWordSize));
+ } else {
+ new_region = MemRegion(bottom(), end());
+ }
+ } else
+ if (i < lgrp_spaces()->length() - 1) { // Middle chunks
+ MutableSpace *ps = lgrp_spaces()->at(i - 1)->space();
+ new_region = MemRegion(ps->end(),
+ ps->end() + (chunk_byte_size >> LogHeapWordSize));
+ } else { // Top chunk
+ MutableSpace *ps = lgrp_spaces()->at(i - 1)->space();
+ new_region = MemRegion(ps->end(), end());
+ }
+ guarantee(region().contains(new_region), "Region invariant");
+
+
+ // The general case:
+ // |---------------------|--invalid---|--------------------------|
+ // |------------------new_region---------------------------------|
+ // |----bottom_region--|---intersection---|------top_region------|
+ // |----old_region----|
+ // The intersection part has all pages in place we don't need to migrate them.
+ // Pages for the top and bottom part should be freed and then reallocated.
+
+ MemRegion intersection = old_region.intersection(new_region);
+
+ if (intersection.start() == NULL || intersection.end() == NULL) {
+ intersection = MemRegion(new_region.start(), new_region.start());
+ }
+
+ if (!os::numa_has_static_binding()) {
+ MemRegion invalid_region = ls->invalid_region().intersection(new_region);
+ // Invalid region is a range of memory that could've possibly
+ // been allocated on the other node. That's relevant only on Solaris where
+ // there is no static memory binding.
+ if (!invalid_region.is_empty()) {
+ merge_regions(new_region, &intersection, &invalid_region);
+ free_region(invalid_region);
+ ls->set_invalid_region(MemRegion());
+ }
+ }
+
+ select_tails(new_region, intersection, &bottom_region, &top_region);
+
+ if (!os::numa_has_static_binding()) {
+ // If that's a system with the first-touch policy then it's enough
+ // to free the pages.
+ free_region(bottom_region);
+ free_region(top_region);
+ } else {
+ // In a system with static binding we have to change the bias whenever
+ // we reshape the heap.
+ bias_region(bottom_region, ls->lgrp_id());
+ bias_region(top_region, ls->lgrp_id());
+ }
+
+ // Clear space (set top = bottom) but never mangle.
+ s->initialize(new_region, SpaceDecorator::Clear, SpaceDecorator::DontMangle, MutableSpace::DontSetupPages);
+
+ set_adaptation_cycles(samples_count());
+ }
+}
+
+// Set the top of the whole space.
+// Mark the the holes in chunks below the top() as invalid.
+void MutableNUMASpace::set_top(HeapWord* value) {
+ bool found_top = false;
+ for (int i = 0; i < lgrp_spaces()->length();) {
+ LGRPSpace *ls = lgrp_spaces()->at(i);
+ MutableSpace *s = ls->space();
+ HeapWord *top = MAX2(align_down(s->top(), page_size()), s->bottom());
+
+ if (s->contains(value)) {
+ // Check if setting the chunk's top to a given value would create a hole less than
+ // a minimal object; assuming that's not the last chunk in which case we don't care.
+ if (i < lgrp_spaces()->length() - 1) {
+ size_t remainder = pointer_delta(s->end(), value);
+ const size_t min_fill_size = CollectedHeap::min_fill_size();
+ if (remainder < min_fill_size && remainder > 0) {
+ // Add a minimum size filler object; it will cross the chunk boundary.
+ CollectedHeap::fill_with_object(value, min_fill_size);
+ value += min_fill_size;
+ assert(!s->contains(value), "Should be in the next chunk");
+ // Restart the loop from the same chunk, since the value has moved
+ // to the next one.
+ continue;
+ }
+ }
+
+ if (!os::numa_has_static_binding() && top < value && top < s->end()) {
+ ls->add_invalid_region(MemRegion(top, value));
+ }
+ s->set_top(value);
+ found_top = true;
+ } else {
+ if (found_top) {
+ s->set_top(s->bottom());
+ } else {
+ if (!os::numa_has_static_binding() && top < s->end()) {
+ ls->add_invalid_region(MemRegion(top, s->end()));
+ }
+ s->set_top(s->end());
+ }
+ }
+ i++;
+ }
+ MutableSpace::set_top(value);
+}
+
+void MutableNUMASpace::clear(bool mangle_space) {
+ MutableSpace::set_top(bottom());
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ // Never mangle NUMA spaces because the mangling will
+ // bind the memory to a possibly unwanted lgroup.
+ lgrp_spaces()->at(i)->space()->clear(SpaceDecorator::DontMangle);
+ }
+}
+
+/*
+ Linux supports static memory binding, therefore the most part of the
+ logic dealing with the possible invalid page allocation is effectively
+ disabled. Besides there is no notion of the home node in Linux. A
+ thread is allowed to migrate freely. Although the scheduler is rather
+ reluctant to move threads between the nodes. We check for the current
+ node every allocation. And with a high probability a thread stays on
+ the same node for some time allowing local access to recently allocated
+ objects.
+ */
+
+HeapWord* MutableNUMASpace::allocate(size_t size) {
+ Thread* thr = Thread::current();
+ int lgrp_id = thr->lgrp_id();
+ if (lgrp_id == -1 || !os::numa_has_group_homing()) {
+ lgrp_id = os::numa_get_group_id();
+ thr->set_lgrp_id(lgrp_id);
+ }
+
+ int i = lgrp_spaces()->find(&lgrp_id, LGRPSpace::equals);
+
+ // It is possible that a new CPU has been hotplugged and
+ // we haven't reshaped the space accordingly.
+ if (i == -1) {
+ i = os::random() % lgrp_spaces()->length();
+ }
+
+ LGRPSpace* ls = lgrp_spaces()->at(i);
+ MutableSpace *s = ls->space();
+ HeapWord *p = s->allocate(size);
+
+ if (p != NULL) {
+ size_t remainder = s->free_in_words();
+ if (remainder < CollectedHeap::min_fill_size() && remainder > 0) {
+ s->set_top(s->top() - size);
+ p = NULL;
+ }
+ }
+ if (p != NULL) {
+ if (top() < s->top()) { // Keep _top updated.
+ MutableSpace::set_top(s->top());
+ }
+ }
+ // Make the page allocation happen here if there is no static binding..
+ if (p != NULL && !os::numa_has_static_binding()) {
+ for (HeapWord *i = p; i < p + size; i += os::vm_page_size() >> LogHeapWordSize) {
+ *(int*)i = 0;
+ }
+ }
+ if (p == NULL) {
+ ls->set_allocation_failed();
+ }
+ return p;
+}
+
+// This version is lock-free.
+HeapWord* MutableNUMASpace::cas_allocate(size_t size) {
+ Thread* thr = Thread::current();
+ int lgrp_id = thr->lgrp_id();
+ if (lgrp_id == -1 || !os::numa_has_group_homing()) {
+ lgrp_id = os::numa_get_group_id();
+ thr->set_lgrp_id(lgrp_id);
+ }
+
+ int i = lgrp_spaces()->find(&lgrp_id, LGRPSpace::equals);
+ // It is possible that a new CPU has been hotplugged and
+ // we haven't reshaped the space accordingly.
+ if (i == -1) {
+ i = os::random() % lgrp_spaces()->length();
+ }
+ LGRPSpace *ls = lgrp_spaces()->at(i);
+ MutableSpace *s = ls->space();
+ HeapWord *p = s->cas_allocate(size);
+ if (p != NULL) {
+ size_t remainder = pointer_delta(s->end(), p + size);
+ if (remainder < CollectedHeap::min_fill_size() && remainder > 0) {
+ if (s->cas_deallocate(p, size)) {
+ // We were the last to allocate and created a fragment less than
+ // a minimal object.
+ p = NULL;
+ } else {
+ guarantee(false, "Deallocation should always succeed");
+ }
+ }
+ }
+ if (p != NULL) {
+ HeapWord* cur_top, *cur_chunk_top = p + size;
+ while ((cur_top = top()) < cur_chunk_top) { // Keep _top updated.
+ if (Atomic::cmpxchg_ptr(cur_chunk_top, top_addr(), cur_top) == cur_top) {
+ break;
+ }
+ }
+ }
+
+ // Make the page allocation happen here if there is no static binding.
+ if (p != NULL && !os::numa_has_static_binding() ) {
+ for (HeapWord *i = p; i < p + size; i += os::vm_page_size() >> LogHeapWordSize) {
+ *(int*)i = 0;
+ }
+ }
+ if (p == NULL) {
+ ls->set_allocation_failed();
+ }
+ return p;
+}
+
+void MutableNUMASpace::print_short_on(outputStream* st) const {
+ MutableSpace::print_short_on(st);
+ st->print(" (");
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ st->print("lgrp %d: ", lgrp_spaces()->at(i)->lgrp_id());
+ lgrp_spaces()->at(i)->space()->print_short_on(st);
+ if (i < lgrp_spaces()->length() - 1) {
+ st->print(", ");
+ }
+ }
+ st->print(")");
+}
+
+void MutableNUMASpace::print_on(outputStream* st) const {
+ MutableSpace::print_on(st);
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ LGRPSpace *ls = lgrp_spaces()->at(i);
+ st->print(" lgrp %d", ls->lgrp_id());
+ ls->space()->print_on(st);
+ if (NUMAStats) {
+ for (int i = 0; i < lgrp_spaces()->length(); i++) {
+ lgrp_spaces()->at(i)->accumulate_statistics(page_size());
+ }
+ st->print(" local/remote/unbiased/uncommitted: " SIZE_FORMAT "K/"
+ SIZE_FORMAT "K/" SIZE_FORMAT "K/" SIZE_FORMAT
+ "K, large/small pages: " SIZE_FORMAT "/" SIZE_FORMAT "\n",
+ ls->space_stats()->_local_space / K,
+ ls->space_stats()->_remote_space / K,
+ ls->space_stats()->_unbiased_space / K,
+ ls->space_stats()->_uncommited_space / K,
+ ls->space_stats()->_large_pages,
+ ls->space_stats()->_small_pages);
+ }
+ }
+}
+
+void MutableNUMASpace::verify() {
+ // This can be called after setting an arbitrary value to the space's top,
+ // so an object can cross the chunk boundary. We ensure the parsability
+ // of the space and just walk the objects in linear fashion.
+ ensure_parsability();
+ MutableSpace::verify();
+}
+
+// Scan pages and gather stats about page placement and size.
+void MutableNUMASpace::LGRPSpace::accumulate_statistics(size_t page_size) {
+ clear_space_stats();
+ char *start = (char*)align_up(space()->bottom(), page_size);
+ char* end = (char*)align_down(space()->end(), page_size);
+ if (start < end) {
+ for (char *p = start; p < end;) {
+ os::page_info info;
+ if (os::get_page_info(p, &info)) {
+ if (info.size > 0) {
+ if (info.size > (size_t)os::vm_page_size()) {
+ space_stats()->_large_pages++;
+ } else {
+ space_stats()->_small_pages++;
+ }
+ if (info.lgrp_id == lgrp_id()) {
+ space_stats()->_local_space += info.size;
+ } else {
+ space_stats()->_remote_space += info.size;
+ }
+ p += info.size;
+ } else {
+ p += os::vm_page_size();
+ space_stats()->_uncommited_space += os::vm_page_size();
+ }
+ } else {
+ return;
+ }
+ }
+ }
+ space_stats()->_unbiased_space = pointer_delta(start, space()->bottom(), sizeof(char)) +
+ pointer_delta(space()->end(), end, sizeof(char));
+
+}
+
+// Scan page_count pages and verify if they have the right size and right placement.
+// If invalid pages are found they are freed in hope that subsequent reallocation
+// will be more successful.
+void MutableNUMASpace::LGRPSpace::scan_pages(size_t page_size, size_t page_count)
+{
+ char* range_start = (char*)align_up(space()->bottom(), page_size);
+ char* range_end = (char*)align_down(space()->end(), page_size);
+
+ if (range_start > last_page_scanned() || last_page_scanned() >= range_end) {
+ set_last_page_scanned(range_start);
+ }
+
+ char *scan_start = last_page_scanned();
+ char* scan_end = MIN2(scan_start + page_size * page_count, range_end);
+
+ os::page_info page_expected, page_found;
+ page_expected.size = page_size;
+ page_expected.lgrp_id = lgrp_id();
+
+ char *s = scan_start;
+ while (s < scan_end) {
+ char *e = os::scan_pages(s, (char*)scan_end, &page_expected, &page_found);
+ if (e == NULL) {
+ break;
+ }
+ if (e != scan_end) {
+ assert(e < scan_end, "e: " PTR_FORMAT " scan_end: " PTR_FORMAT, p2i(e), p2i(scan_end));
+
+ if ((page_expected.size != page_size || page_expected.lgrp_id != lgrp_id())
+ && page_expected.size != 0) {
+ os::free_memory(s, pointer_delta(e, s, sizeof(char)), page_size);
+ }
+ page_expected = page_found;
+ }
+ s = e;
+ }
+
+ set_last_page_scanned(scan_end);
+}