diff options
Diffstat (limited to 'src/share/vm/gc_implementation/g1/g1PageBasedVirtualSpace.cpp')
| -rw-r--r-- | src/share/vm/gc_implementation/g1/g1PageBasedVirtualSpace.cpp | 165 |
1 files changed, 126 insertions, 39 deletions
diff --git a/src/share/vm/gc_implementation/g1/g1PageBasedVirtualSpace.cpp b/src/share/vm/gc_implementation/g1/g1PageBasedVirtualSpace.cpp index 662d28aee..1a22af82a 100644 --- a/src/share/vm/gc_implementation/g1/g1PageBasedVirtualSpace.cpp +++ b/src/share/vm/gc_implementation/g1/g1PageBasedVirtualSpace.cpp @@ -1,5 +1,5 @@ /* - * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved. + * 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 @@ -44,20 +44,29 @@ #endif #include "utilities/bitMap.inline.hpp" -G1PageBasedVirtualSpace::G1PageBasedVirtualSpace() : _low_boundary(NULL), - _high_boundary(NULL), _committed(), _page_size(0), _special(false), +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); } -bool G1PageBasedVirtualSpace::initialize_with_granularity(ReservedSpace rs, size_t page_size) { - if (!rs.is_reserved()) { - return false; // Allocation failed. - } +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."); + assert(_low_boundary == NULL, "VirtualSpace already initialized"); - assert(page_size > 0, "Granularity must be non-zero."); + assert(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 + rs.size(); + _high_boundary = _low_boundary + used_size; _special = rs.special(); _executable = rs.executable(); @@ -65,16 +74,15 @@ bool G1PageBasedVirtualSpace::initialize_with_granularity(ReservedSpace rs, size _page_size = page_size; assert(_committed.size() == 0, "virtual space initialized more than once"); - uintx size_in_bits = rs.size() / page_size; - _committed.resize(size_in_bits, /* in_resource_area */ false); + 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_bits, /* in_resource_area */ false); + _dirty.resize(size_in_pages, /* in_resource_area */ false); } - return true; + _tail_size = used_size % _page_size; } - G1PageBasedVirtualSpace::~G1PageBasedVirtualSpace() { release(); } @@ -87,12 +95,18 @@ void G1PageBasedVirtualSpace::release() { _special = false; _executable = false; _page_size = 0; + _tail_size = 0; _committed.resize(0, false); _dirty.resize(0, false); } size_t G1PageBasedVirtualSpace::committed_size() const { - return _committed.count_one_bits() * _page_size; + 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 { @@ -103,62 +117,134 @@ size_t G1PageBasedVirtualSpace::uncommitted_size() const { return reserved_size() - committed_size(); } -uintptr_t G1PageBasedVirtualSpace::addr_to_page_index(char* addr) const { +size_t G1PageBasedVirtualSpace::addr_to_page_index(char* addr) const { return (addr - _low_boundary) / _page_size; } -bool G1PageBasedVirtualSpace::is_area_committed(uintptr_t start, size_t size_in_pages) const { - uintptr_t end = start + size_in_pages; - return _committed.get_next_zero_offset(start, end) >= end; +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(uintptr_t start, size_t size_in_pages) const { - uintptr_t end = start + size_in_pages; - return _committed.get_next_one_offset(start, end) >= end; +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(uintptr_t index) { +char* G1PageBasedVirtualSpace::page_start(size_t index) const { return _low_boundary + index * _page_size; } -size_t G1PageBasedVirtualSpace::byte_size_for_pages(size_t num) { - return num * _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) { + assert(num_pages > 0, "No full pages to commit"); + assert(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() { + assert(_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)); } -bool G1PageBasedVirtualSpace::commit(uintptr_t start, size_t size_in_pages) { +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, size_in_pages), "Specified area is not uncommitted"); + guarantee(is_area_uncommitted(start_page, size_in_pages), "Specified area is not uncommitted"); bool zero_filled = true; - uintptr_t end = start + size_in_pages; + 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,end) < end) { + if (_dirty.get_next_one_offset(start_page, end_page) < end_page) { zero_filled = false; - _dirty.clear_range(start, end); + _dirty.clear_range(start_page, end_page); } } else { - os::commit_memory_or_exit(page_start(start), byte_size_for_pages(size_in_pages), _executable, - err_msg("Failed to commit pages from "SIZE_FORMAT" of length "SIZE_FORMAT, start, size_in_pages)); + commit_internal(start_page, end_page); } - _committed.set_range(start, end); + _committed.set_range(start_page, end_page); + if (AlwaysPreTouch) { + pretouch_internal(start_page, end_page); + } return zero_filled; } -void G1PageBasedVirtualSpace::uncommit(uintptr_t start, size_t size_in_pages) { - guarantee(is_area_committed(start, size_in_pages), "checking"); +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, start + size_in_pages); + _dirty.set_range(start_page, end_page); } else { - os::uncommit_memory(page_start(start), byte_size_for_pages(size_in_pages)); + uncommit_internal(start_page, end_page); } - _committed.clear_range(start, start + size_in_pages); + _committed.clear_range(start_page, end_page); } bool G1PageBasedVirtualSpace::contains(const void* p) const { @@ -172,7 +258,8 @@ void G1PageBasedVirtualSpace::print_on(outputStream* out) { out->cr(); out->print_cr(" - committed: " SIZE_FORMAT, committed_size()); out->print_cr(" - reserved: " SIZE_FORMAT, reserved_size()); - out->print_cr(" - [low_b, high_b]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", p2i(_low_boundary), p2i(_high_boundary)); + 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() { |