--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc/g1/g1PageBasedVirtualSpace.cpp Wed May 13 15:16:06 2015 +0200
@@ -0,0 +1,268 @@
+/*
+ * Copyright (c) 2014, 2015, 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/g1/g1PageBasedVirtualSpace.hpp"
+#include "oops/markOop.hpp"
+#include "oops/oop.inline.hpp"
+#include "services/memTracker.hpp"
+#ifdef TARGET_OS_FAMILY_linux
+# include "os_linux.inline.hpp"
+#endif
+#ifdef TARGET_OS_FAMILY_solaris
+# include "os_solaris.inline.hpp"
+#endif
+#ifdef TARGET_OS_FAMILY_windows
+# include "os_windows.inline.hpp"
+#endif
+#ifdef TARGET_OS_FAMILY_aix
+# include "os_aix.inline.hpp"
+#endif
+#ifdef TARGET_OS_FAMILY_bsd
+# include "os_bsd.inline.hpp"
+#endif
+#include "utilities/bitMap.inline.hpp"
+
+G1PageBasedVirtualSpace::G1PageBasedVirtualSpace(ReservedSpace rs, size_t used_size, size_t page_size) :
+ _low_boundary(NULL), _high_boundary(NULL), _committed(), _page_size(0), _special(false),
+ _dirty(), _executable(false) {
+ initialize_with_page_size(rs, used_size, page_size);
+}
+
+void G1PageBasedVirtualSpace::initialize_with_page_size(ReservedSpace rs, size_t used_size, size_t page_size) {
+ guarantee(rs.is_reserved(), "Given reserved space must have been reserved already.");
+
+ vmassert(_low_boundary == NULL, "VirtualSpace already initialized");
+ vmassert(page_size > 0, "Page size must be non-zero.");
+
+ guarantee(is_ptr_aligned(rs.base(), page_size),
+ err_msg("Reserved space base " PTR_FORMAT " is not aligned to requested page size " SIZE_FORMAT, p2i(rs.base()), page_size));
+ guarantee(is_size_aligned(used_size, os::vm_page_size()),
+ err_msg("Given used reserved space size needs to be OS page size aligned (%d bytes) but is " SIZE_FORMAT, os::vm_page_size(), used_size));
+ guarantee(used_size <= rs.size(),
+ err_msg("Used size of reserved space " SIZE_FORMAT " bytes is smaller than reservation at " SIZE_FORMAT " bytes", used_size, rs.size()));
+ guarantee(is_size_aligned(rs.size(), page_size),
+ err_msg("Expected that the virtual space is size aligned, but " SIZE_FORMAT " is not aligned to page size " SIZE_FORMAT, rs.size(), page_size));
+
+ _low_boundary = rs.base();
+ _high_boundary = _low_boundary + used_size;
+
+ _special = rs.special();
+ _executable = rs.executable();
+
+ _page_size = page_size;
+
+ vmassert(_committed.size() == 0, "virtual space initialized more than once");
+ BitMap::idx_t size_in_pages = rs.size() / page_size;
+ _committed.resize(size_in_pages, /* in_resource_area */ false);
+ if (_special) {
+ _dirty.resize(size_in_pages, /* in_resource_area */ false);
+ }
+
+ _tail_size = used_size % _page_size;
+}
+
+G1PageBasedVirtualSpace::~G1PageBasedVirtualSpace() {
+ release();
+}
+
+void G1PageBasedVirtualSpace::release() {
+ // This does not release memory it never reserved.
+ // Caller must release via rs.release();
+ _low_boundary = NULL;
+ _high_boundary = NULL;
+ _special = false;
+ _executable = false;
+ _page_size = 0;
+ _tail_size = 0;
+ _committed.resize(0, false);
+ _dirty.resize(0, false);
+}
+
+size_t G1PageBasedVirtualSpace::committed_size() const {
+ size_t result = _committed.count_one_bits() * _page_size;
+ // The last page might not be in full.
+ if (is_last_page_partial() && _committed.at(_committed.size() - 1)) {
+ result -= _page_size - _tail_size;
+ }
+ return result;
+}
+
+size_t G1PageBasedVirtualSpace::reserved_size() const {
+ return pointer_delta(_high_boundary, _low_boundary, sizeof(char));
+}
+
+size_t G1PageBasedVirtualSpace::uncommitted_size() const {
+ return reserved_size() - committed_size();
+}
+
+size_t G1PageBasedVirtualSpace::addr_to_page_index(char* addr) const {
+ return (addr - _low_boundary) / _page_size;
+}
+
+bool G1PageBasedVirtualSpace::is_area_committed(size_t start_page, size_t size_in_pages) const {
+ size_t end_page = start_page + size_in_pages;
+ return _committed.get_next_zero_offset(start_page, end_page) >= end_page;
+}
+
+bool G1PageBasedVirtualSpace::is_area_uncommitted(size_t start_page, size_t size_in_pages) const {
+ size_t end_page = start_page + size_in_pages;
+ return _committed.get_next_one_offset(start_page, end_page) >= end_page;
+}
+
+char* G1PageBasedVirtualSpace::page_start(size_t index) const {
+ return _low_boundary + index * _page_size;
+}
+
+bool G1PageBasedVirtualSpace::is_after_last_page(size_t index) const {
+ guarantee(index <= _committed.size(),
+ err_msg("Given boundary page " SIZE_FORMAT " is beyond managed page count " SIZE_FORMAT, index, _committed.size()));
+ return index == _committed.size();
+}
+
+void G1PageBasedVirtualSpace::commit_preferred_pages(size_t start, size_t num_pages) {
+ vmassert(num_pages > 0, "No full pages to commit");
+ vmassert(start + num_pages <= _committed.size(),
+ err_msg("Tried to commit area from page " SIZE_FORMAT " to page " SIZE_FORMAT " "
+ "that is outside of managed space of " SIZE_FORMAT " pages",
+ start, start + num_pages, _committed.size()));
+
+ char* start_addr = page_start(start);
+ size_t size = num_pages * _page_size;
+
+ os::commit_memory_or_exit(start_addr, size, _page_size, _executable,
+ err_msg("Failed to commit area from " PTR_FORMAT " to " PTR_FORMAT " of length " SIZE_FORMAT ".",
+ p2i(start_addr), p2i(start_addr + size), size));
+}
+
+void G1PageBasedVirtualSpace::commit_tail() {
+ vmassert(_tail_size > 0, "The size of the tail area must be > 0 when reaching here");
+
+ char* const aligned_end_address = (char*)align_ptr_down(_high_boundary, _page_size);
+ os::commit_memory_or_exit(aligned_end_address, _tail_size, os::vm_page_size(), _executable,
+ err_msg("Failed to commit tail area from " PTR_FORMAT " to " PTR_FORMAT " of length " SIZE_FORMAT ".",
+ p2i(aligned_end_address), p2i(_high_boundary), _tail_size));
+}
+
+void G1PageBasedVirtualSpace::commit_internal(size_t start_page, size_t end_page) {
+ guarantee(start_page < end_page,
+ err_msg("Given start page " SIZE_FORMAT " is larger or equal to end page " SIZE_FORMAT, start_page, end_page));
+ guarantee(end_page <= _committed.size(),
+ err_msg("Given end page " SIZE_FORMAT " is beyond end of managed page amount of " SIZE_FORMAT, end_page, _committed.size()));
+
+ size_t pages = end_page - start_page;
+ bool need_to_commit_tail = is_after_last_page(end_page) && is_last_page_partial();
+
+ // If we have to commit some (partial) tail area, decrease the amount of pages to avoid
+ // committing that in the full-page commit code.
+ if (need_to_commit_tail) {
+ pages--;
+ }
+
+ if (pages > 0) {
+ commit_preferred_pages(start_page, pages);
+ }
+
+ if (need_to_commit_tail) {
+ commit_tail();
+ }
+}
+
+char* G1PageBasedVirtualSpace::bounded_end_addr(size_t end_page) const {
+ return MIN2(_high_boundary, page_start(end_page));
+}
+
+void G1PageBasedVirtualSpace::pretouch_internal(size_t start_page, size_t end_page) {
+ guarantee(start_page < end_page,
+ err_msg("Given start page " SIZE_FORMAT " is larger or equal to end page " SIZE_FORMAT, start_page, end_page));
+
+ os::pretouch_memory(page_start(start_page), bounded_end_addr(end_page));
+}
+
+bool G1PageBasedVirtualSpace::commit(size_t start_page, size_t size_in_pages) {
+ // We need to make sure to commit all pages covered by the given area.
+ guarantee(is_area_uncommitted(start_page, size_in_pages), "Specified area is not uncommitted");
+
+ bool zero_filled = true;
+ size_t end_page = start_page + size_in_pages;
+
+ if (_special) {
+ // Check for dirty pages and update zero_filled if any found.
+ if (_dirty.get_next_one_offset(start_page, end_page) < end_page) {
+ zero_filled = false;
+ _dirty.clear_range(start_page, end_page);
+ }
+ } else {
+ commit_internal(start_page, end_page);
+ }
+ _committed.set_range(start_page, end_page);
+
+ if (AlwaysPreTouch) {
+ pretouch_internal(start_page, end_page);
+ }
+ return zero_filled;
+}
+
+void G1PageBasedVirtualSpace::uncommit_internal(size_t start_page, size_t end_page) {
+ guarantee(start_page < end_page,
+ err_msg("Given start page " SIZE_FORMAT " is larger or equal to end page " SIZE_FORMAT, start_page, end_page));
+
+ char* start_addr = page_start(start_page);
+ os::uncommit_memory(start_addr, pointer_delta(bounded_end_addr(end_page), start_addr, sizeof(char)));
+}
+
+void G1PageBasedVirtualSpace::uncommit(size_t start_page, size_t size_in_pages) {
+ guarantee(is_area_committed(start_page, size_in_pages), "checking");
+
+ size_t end_page = start_page + size_in_pages;
+ if (_special) {
+ // Mark that memory is dirty. If committed again the memory might
+ // need to be cleared explicitly.
+ _dirty.set_range(start_page, end_page);
+ } else {
+ uncommit_internal(start_page, end_page);
+ }
+
+ _committed.clear_range(start_page, end_page);
+}
+
+bool G1PageBasedVirtualSpace::contains(const void* p) const {
+ return _low_boundary <= (const char*) p && (const char*) p < _high_boundary;
+}
+
+#ifndef PRODUCT
+void G1PageBasedVirtualSpace::print_on(outputStream* out) {
+ out->print ("Virtual space:");
+ if (_special) out->print(" (pinned in memory)");
+ out->cr();
+ out->print_cr(" - committed: " SIZE_FORMAT, committed_size());
+ out->print_cr(" - reserved: " SIZE_FORMAT, reserved_size());
+ out->print_cr(" - preferred page size: " SIZE_FORMAT, _page_size);
+ out->print_cr(" - [low_b, high_b]: [" PTR_FORMAT ", " PTR_FORMAT "]", p2i(_low_boundary), p2i(_high_boundary));
+}
+
+void G1PageBasedVirtualSpace::print() {
+ print_on(tty);
+}
+#endif