| /* |
| * Copyright (c) 2017, 2018, 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 "jfr/recorder/storage/jfrVirtualMemory.hpp" |
| #include "memory/virtualspace.hpp" |
| #include "runtime/globals.hpp" |
| #include "runtime/os.hpp" |
| #include "services/memTracker.hpp" |
| #include "utilities/globalDefinitions.hpp" |
| |
| /* |
| * A memory segment represents a virtual memory reservation. |
| * It provides ways to commit and decommit physical storage |
| * onto its virtual memory reservation. |
| */ |
| |
| class JfrVirtualMemorySegment : public JfrCHeapObj { |
| friend class JfrVirtualMemoryManager; |
| private: |
| JfrVirtualMemorySegment* _next; |
| char* _top; |
| ReservedSpace _rs; |
| VirtualSpace _virtual_memory; |
| |
| // Convenience functions to access the underlying virtual space metadata |
| const u1* committed_low() const { return (const u1*)_virtual_memory.low(); } |
| const u1* committed_high() const { return (const u1*)_virtual_memory.high(); } |
| const u1* reserved_low() const { return (const u1*)_virtual_memory.low_boundary(); } |
| const u1* reserved_high() const { return (const u1*)_virtual_memory.high_boundary(); } |
| size_t reserved_words() const { return _virtual_memory.reserved_size() / BytesPerWord; } |
| size_t committed_words() const { return _virtual_memory.actual_committed_size() / BytesPerWord; } |
| bool is_pre_committed() const { return _virtual_memory.special(); } |
| VirtualSpace& virtual_space() { return _virtual_memory; } |
| |
| JfrVirtualMemorySegment(); |
| ~JfrVirtualMemorySegment(); |
| |
| JfrVirtualMemorySegment* next() const { return _next; } |
| void set_next(JfrVirtualMemorySegment* v) { _next = v; } |
| |
| // Returns true if requested size is available in the committed area |
| bool is_available(size_t block_size_request_words) { |
| return block_size_request_words <= pointer_delta(committed_high(), _top, sizeof(char*)); |
| } |
| |
| // allocation pointer committed memory |
| char* top() const { return _top; } |
| void inc_top(size_t size_in_words) { |
| assert(is_available(size_in_words), "invariant"); |
| _top += size_in_words * BytesPerWord; |
| assert(_top <= _virtual_memory.high(), "invariant"); |
| } |
| |
| // initialization is the virtual memory reservation |
| bool initialize(size_t reservation_size_request_bytes); |
| void* take_from_committed(size_t block_size_request_words); |
| |
| // Returns committed memory |
| void* commit(size_t block_size_request_words) { |
| return take_from_committed(block_size_request_words); |
| } |
| |
| // Commit more memory in a reservation |
| bool expand_by(size_t block_size_request_words); |
| |
| // Decommits all committed memory in this reservation segment. |
| void decommit(); |
| }; |
| |
| JfrVirtualMemorySegment::JfrVirtualMemorySegment() : |
| _next(NULL), |
| _top(NULL), |
| _rs(), |
| _virtual_memory() {} |
| |
| JfrVirtualMemorySegment::~JfrVirtualMemorySegment() { |
| decommit(); |
| _rs.release(); |
| } |
| |
| bool JfrVirtualMemorySegment::initialize(size_t reservation_size_request_bytes) { |
| assert(is_aligned(reservation_size_request_bytes, os::vm_allocation_granularity()), "invariant"); |
| _rs = ReservedSpace(reservation_size_request_bytes, |
| os::vm_allocation_granularity(), |
| UseLargePages && os::can_commit_large_page_memory(), |
| false); |
| if (!_rs.is_reserved()) { |
| return false; |
| } |
| assert(_rs.base() != NULL, "invariant"); |
| assert(_rs.size() != 0, "invariant"); |
| assert(is_aligned(_rs.base(), os::vm_allocation_granularity()), "invariant"); |
| assert(is_aligned(_rs.size(), os::vm_allocation_granularity()), "invariant"); |
| os::trace_page_sizes("Jfr", reservation_size_request_bytes, |
| reservation_size_request_bytes, |
| os::vm_page_size(), |
| _rs.base(), |
| _rs.size()); |
| MemTracker::record_virtual_memory_type((address)_rs.base(), mtTracing); |
| assert(is_aligned(_rs.base(), os::vm_page_size()), "invariant"); |
| assert(is_aligned(_rs.size(), os::vm_page_size()), "invariant"); |
| |
| // ReservedSpaces marked as special will have the entire memory |
| // pre-committed. Setting a committed size will make sure that |
| // committed_size and actual_committed_size agrees. |
| const size_t pre_committed_size = _rs.special() ? _rs.size() : 0; |
| const bool result = virtual_space().initialize_with_granularity(_rs, pre_committed_size, os::vm_page_size()); |
| |
| if (result) { |
| assert(virtual_space().committed_size() == virtual_space().actual_committed_size(), |
| "Checking that the pre-committed memory was registered by the VirtualSpace"); |
| _top = virtual_space().low(); |
| } |
| return result; |
| } |
| |
| bool JfrVirtualMemorySegment::expand_by(size_t block_size_request_words) { |
| size_t block_size_request_bytes = block_size_request_words * BytesPerWord; |
| const size_t uncommitted = virtual_space().reserved_size() - virtual_space().actual_committed_size(); |
| if (uncommitted < block_size_request_bytes) { |
| // commit whatever is left in the reservation |
| block_size_request_bytes = uncommitted; |
| } |
| assert(is_aligned(block_size_request_bytes, os::vm_allocation_granularity()), "invariant"); |
| // commit block in reserved memory |
| bool result = virtual_space().expand_by(block_size_request_bytes, false); |
| assert(result, "Failed to commit memory"); |
| return result; |
| } |
| |
| void JfrVirtualMemorySegment::decommit() { |
| assert(_virtual_memory.committed_size() == _virtual_memory.actual_committed_size(), |
| "The committed memory doesn't match the expanded memory."); |
| |
| const size_t committed_size = virtual_space().actual_committed_size(); |
| if (committed_size > 0) { |
| virtual_space().shrink_by(committed_size); |
| } |
| |
| assert(_virtual_memory.actual_committed_size() == 0, "invariant"); |
| } |
| |
| // Attempt to get a committed block |
| void* JfrVirtualMemorySegment::take_from_committed(size_t block_size_request_words) { |
| // The virtual spaces are always expanded by the |
| // commit granularity to enforce the following condition. |
| // Without this the is_available check will not work correctly. |
| assert(_virtual_memory.committed_size() == _virtual_memory.actual_committed_size(), |
| "The committed memory doesn't match the expanded memory."); |
| if (!is_available(block_size_request_words)) { |
| return NULL; |
| } |
| void* const block = top(); |
| assert(block != NULL, "invariant"); |
| inc_top(block_size_request_words); |
| return block; |
| } |
| |
| class JfrVirtualMemoryManager : public JfrCHeapObj { |
| typedef JfrVirtualMemorySegment Segment; |
| private: |
| Segment* _segments; |
| Segment* _current_segment; |
| size_t _reservation_size_request_words; |
| size_t _reservation_size_request_limit_words; // total reservation limit |
| |
| // Sum of reserved and committed memory in the segments |
| size_t _current_reserved_words; |
| size_t _current_committed_words; |
| |
| void link(Segment* segment); |
| Segment* current(); |
| |
| void inc_reserved_words(size_t words); |
| void inc_committed_words(size_t words); |
| |
| bool new_segment(size_t reservation_size_request_words); |
| |
| bool expand_segment_by(Segment* segment, size_t block_size_request_words); |
| |
| bool expand_by(size_t block_size_request_words, size_t reservation_size_request_words); |
| bool can_reserve() const; |
| |
| public: |
| JfrVirtualMemoryManager(); |
| ~JfrVirtualMemoryManager(); |
| |
| bool initialize(size_t reservation_size_request_words, size_t segment_count = 1); |
| void* commit(size_t requested_block_size_words); |
| |
| bool is_full() const { |
| return reserved_high() == committed_high(); |
| } |
| |
| const u1* committed_low() const { return _current_segment->committed_low(); } |
| const u1* committed_high() const { return _current_segment->committed_high(); } |
| const u1* reserved_low() const { return _current_segment->reserved_low(); } |
| const u1* reserved_high() const { return _current_segment->reserved_high(); } |
| }; |
| |
| JfrVirtualMemoryManager::JfrVirtualMemoryManager() : |
| _segments(NULL), |
| _current_segment(NULL), |
| _reservation_size_request_words(0), |
| _reservation_size_request_limit_words(0), |
| _current_reserved_words(0), |
| _current_committed_words(0) {} |
| |
| JfrVirtualMemoryManager::~JfrVirtualMemoryManager() { |
| JfrVirtualMemorySegment* segment = _segments; |
| while (segment != NULL) { |
| JfrVirtualMemorySegment* next_segment = segment->next(); |
| delete segment; |
| segment = next_segment; |
| } |
| } |
| |
| // for now only allow a singleton segment per virtual memory client |
| bool JfrVirtualMemoryManager::initialize(size_t reservation_size_request_words, size_t segment_count /* 1 */) { |
| assert(is_aligned(reservation_size_request_words * BytesPerWord, os::vm_allocation_granularity()), "invariant"); |
| _reservation_size_request_words = reservation_size_request_words; |
| assert(segment_count > 0, "invariant"); |
| _reservation_size_request_limit_words = reservation_size_request_words * segment_count; |
| assert(is_aligned(_reservation_size_request_limit_words * BytesPerWord, os::vm_allocation_granularity()), "invariant"); |
| return new_segment(_reservation_size_request_words); |
| } |
| |
| bool JfrVirtualMemoryManager::can_reserve() const { |
| return _reservation_size_request_limit_words == 0 ? true : _current_reserved_words < _reservation_size_request_limit_words; |
| } |
| |
| // Allocate another segment and add it to the list. |
| bool JfrVirtualMemoryManager::new_segment(size_t reservation_size_request_words) { |
| assert(reservation_size_request_words > 0, "invariant"); |
| assert(is_aligned(reservation_size_request_words * BytesPerWord, os::vm_allocation_granularity()), "invariant"); |
| Segment* segment = new Segment(); |
| if (NULL == segment) { |
| return false; |
| } |
| if (!segment->initialize(reservation_size_request_words * BytesPerWord)) { |
| delete segment; |
| return false; |
| } |
| assert(segment->reserved_words() == reservation_size_request_words, |
| "Actual reserved memory size differs from requested reservation memory size"); |
| link(segment); |
| return true; |
| } |
| |
| bool JfrVirtualMemoryManager::expand_segment_by(JfrVirtualMemorySegment* segment, size_t block_size_request_words) { |
| assert(segment != NULL, "invariant"); |
| const size_t before = segment->committed_words(); |
| const bool result = segment->expand_by(block_size_request_words); |
| const size_t after = segment->committed_words(); |
| // after and before can be the same if the memory was pre-committed. |
| assert(after >= before, "Inconsistency"); |
| inc_committed_words(after - before); |
| return result; |
| } |
| |
| void JfrVirtualMemoryManager::inc_reserved_words(size_t words) { |
| _current_reserved_words += words; |
| } |
| |
| JfrVirtualMemorySegment* JfrVirtualMemoryManager::current() { |
| return _current_segment; |
| } |
| |
| void JfrVirtualMemoryManager::inc_committed_words(size_t words) { |
| _current_committed_words += words; |
| } |
| |
| bool JfrVirtualMemoryManager::expand_by(size_t block_size_request_words, size_t reservation_size_request_words) { |
| assert(is_aligned(block_size_request_words * BytesPerWord, os::vm_page_size()), "invariant"); |
| assert(is_aligned(block_size_request_words * BytesPerWord, os::vm_allocation_granularity()), "invariant"); |
| assert(is_aligned(reservation_size_request_words * BytesPerWord, os::vm_page_size()), "invariant"); |
| assert(is_aligned(reservation_size_request_words * BytesPerWord, os::vm_allocation_granularity()), "invariant"); |
| assert(block_size_request_words <= reservation_size_request_words, "invariant"); |
| // Attempt to commit more memory from the the current virtual space reservation. |
| if (expand_segment_by(current(), block_size_request_words)) { |
| return true; |
| } |
| |
| // reached limit of what is allowed to be reserved? |
| if (!can_reserve()) { |
| return false; |
| } |
| |
| // Get another segment. |
| if (!new_segment(reservation_size_request_words)) { |
| return false; |
| } |
| |
| if (current()->is_pre_committed()) { |
| // The memory was pre-committed, so we are done here. |
| assert(block_size_request_words <= current()->committed_words(), |
| "The new VirtualSpace was pre-committed, so it" |
| "should be large enough to fit the alloc request."); |
| return true; |
| } |
| return expand_segment_by(current(), block_size_request_words); |
| } |
| |
| void JfrVirtualMemoryManager::link(JfrVirtualMemorySegment* segment) { |
| assert(segment != NULL, "invariant"); |
| if (_segments == NULL) { |
| _segments = segment; |
| } else { |
| assert(_current_segment != NULL, "invariant"); |
| assert(_segments == _current_segment, "invariant"); |
| _current_segment->set_next(segment); |
| } |
| _current_segment = segment; |
| inc_reserved_words(segment->reserved_words()); |
| inc_committed_words(segment->committed_words()); |
| } |
| |
| void* JfrVirtualMemoryManager::commit(size_t block_size_request_words) { |
| assert(is_aligned(block_size_request_words * BytesPerWord, os::vm_allocation_granularity()), "invariant"); |
| void* block = current()->commit(block_size_request_words); |
| if (block != NULL) { |
| return block; |
| } |
| assert(block == NULL, "invariant"); |
| if (is_full()) { |
| return NULL; |
| } |
| assert(block_size_request_words <= _reservation_size_request_words, "invariant"); |
| if (expand_by(block_size_request_words, _reservation_size_request_words)) { |
| block = current()->commit(block_size_request_words); |
| assert(block != NULL, "The allocation was expected to succeed after the expansion"); |
| } |
| return block; |
| } |
| |
| JfrVirtualMemory::JfrVirtualMemory() : |
| _vmm(NULL), |
| _reserved_low(), |
| _reserved_high(), |
| _top(NULL), |
| _commit_point(NULL), |
| _physical_commit_size_request_words(0), |
| _aligned_datum_size_bytes(0) {} |
| |
| JfrVirtualMemory::~JfrVirtualMemory() { |
| assert(_vmm != NULL, "invariant"); |
| delete _vmm; |
| } |
| |
| size_t JfrVirtualMemory::aligned_datum_size_bytes() const { |
| return _aligned_datum_size_bytes; |
| } |
| |
| static void adjust_allocation_ratio(size_t* const reservation_size_bytes, size_t* const commit_size_bytes) { |
| assert(reservation_size_bytes != NULL, "invariant"); |
| assert(*reservation_size_bytes > 0, "invariant"); |
| assert(commit_size_bytes != NULL, "invariant"); |
| assert(*commit_size_bytes > 0, "invariant"); |
| assert(*reservation_size_bytes >= *commit_size_bytes, "invariant"); |
| assert(is_aligned(*reservation_size_bytes, os::vm_allocation_granularity()), "invariant"); |
| assert(is_aligned(*commit_size_bytes, os::vm_allocation_granularity()), "invariant"); |
| |
| size_t reservation_size_units = *reservation_size_bytes / os::vm_allocation_granularity(); |
| size_t commit_size_units = *commit_size_bytes / os::vm_allocation_granularity(); |
| assert(reservation_size_units > 0, "invariant"); |
| assert(commit_size_units > 0, "invariant"); |
| |
| size_t original_ratio_units = reservation_size_units / commit_size_units; |
| size_t rem = reservation_size_units % commit_size_units; |
| assert(original_ratio_units > 0, "invariant"); |
| |
| if (rem > 0) { |
| reservation_size_units -= rem % original_ratio_units; |
| commit_size_units += rem / original_ratio_units; |
| } |
| |
| assert(commit_size_units > 0, "invariant"); |
| assert(reservation_size_units % original_ratio_units == 0, "invariant"); |
| assert(original_ratio_units * commit_size_units == reservation_size_units , "invariant"); |
| assert(original_ratio_units == reservation_size_units / commit_size_units, "invariant"); |
| *reservation_size_bytes = reservation_size_units * os::vm_allocation_granularity(); |
| *commit_size_bytes = commit_size_units * os::vm_allocation_granularity(); |
| assert((*reservation_size_bytes % *commit_size_bytes) == 0, "invariant"); |
| } |
| |
| |
| void* JfrVirtualMemory::initialize(size_t reservation_size_request_bytes, |
| size_t block_size_request_bytes, |
| size_t datum_size_bytes /* 1 */) { |
| assert(_vmm == NULL, "invariant"); |
| _vmm = new JfrVirtualMemoryManager(); |
| |
| if (_vmm == NULL) { |
| return NULL; |
| } |
| |
| assert(reservation_size_request_bytes > 0, "invariant"); |
| _aligned_datum_size_bytes = align_up(datum_size_bytes, BytesPerWord); |
| assert(is_aligned(_aligned_datum_size_bytes, BytesPerWord), "invariant"); |
| |
| reservation_size_request_bytes = ReservedSpace::allocation_align_size_up(reservation_size_request_bytes); |
| assert(is_aligned(reservation_size_request_bytes, os::vm_allocation_granularity()), "invariant"); |
| assert(is_aligned(reservation_size_request_bytes, _aligned_datum_size_bytes), "invariant"); |
| block_size_request_bytes = MAX2(block_size_request_bytes, (size_t)os::vm_allocation_granularity()); |
| block_size_request_bytes = ReservedSpace::allocation_align_size_up(block_size_request_bytes); |
| assert(is_aligned(block_size_request_bytes, os::vm_allocation_granularity()), "invariant"); |
| assert(is_aligned(block_size_request_bytes, _aligned_datum_size_bytes), "invariant"); |
| // adjustment to valid ratio in units of vm_allocation_granularity |
| adjust_allocation_ratio(&reservation_size_request_bytes, &block_size_request_bytes); |
| assert(is_aligned(reservation_size_request_bytes, os::vm_allocation_granularity()), "invariant"); |
| assert(is_aligned(reservation_size_request_bytes, _aligned_datum_size_bytes), "invariant"); |
| assert(is_aligned(block_size_request_bytes, os::vm_allocation_granularity()), "invariant"); |
| assert(is_aligned(block_size_request_bytes, _aligned_datum_size_bytes), "invariant"); |
| assert((reservation_size_request_bytes % block_size_request_bytes) == 0, "invariant"); |
| const size_t reservation_size_request_words = reservation_size_request_bytes / BytesPerWord; |
| _physical_commit_size_request_words = block_size_request_bytes / BytesPerWord; |
| // virtual memory reservation |
| if (!_vmm->initialize(reservation_size_request_words)) { |
| // is implicitly "full" if reservation fails |
| assert(is_full(), "invariant"); |
| return NULL; |
| } |
| _reserved_low = (const u1*)_vmm->reserved_low(); |
| _reserved_high = (const u1*)_vmm->reserved_high(); |
| // reservation complete |
| _top = (u1*)_vmm->committed_high(); |
| _commit_point = _top; |
| assert(_reserved_low == _top, "invariant"); // initial empty state |
| assert((size_t)(_reserved_high - _reserved_low) == reservation_size_request_bytes, "invariant"); |
| // initial commit |
| commit_memory_block(); |
| return _top; |
| } |
| |
| void* JfrVirtualMemory::commit(size_t block_size_request_words) { |
| assert(_vmm != NULL, "invariant"); |
| assert(is_aligned(block_size_request_words * BytesPerWord, os::vm_allocation_granularity()), "invariant"); |
| return _vmm->commit(block_size_request_words); |
| } |
| |
| bool JfrVirtualMemory::is_full() const { |
| return _top == _reserved_high; |
| } |
| |
| bool JfrVirtualMemory::is_empty() const { |
| return _top == _reserved_low; |
| } |
| |
| bool JfrVirtualMemory::commit_memory_block() { |
| assert(_vmm != NULL, "invariant"); |
| assert(!is_full(), "invariant"); |
| assert(_top == _commit_point, "invariant"); |
| |
| void* const block = _vmm->commit(_physical_commit_size_request_words); |
| if (block != NULL) { |
| _commit_point = _vmm->committed_high(); |
| return true; |
| } |
| // all reserved virtual memory is committed |
| assert(block == NULL, "invariant"); |
| assert(_vmm->reserved_high() == _vmm->committed_high(), "invariant"); |
| return false; |
| } |
| |
| void* JfrVirtualMemory::new_datum() { |
| assert(_vmm != NULL, "invariant"); |
| assert(!is_full(), "invariant"); |
| if (_top == _commit_point) { |
| if (!commit_memory_block()) { |
| assert(is_full(), "invariant"); |
| return NULL; |
| } |
| } |
| assert(_top + _aligned_datum_size_bytes <= _commit_point, "invariant"); |
| u1* allocation = _top; |
| _top += _aligned_datum_size_bytes; |
| assert(is_aligned(allocation, _aligned_datum_size_bytes), "invariant"); |
| return allocation; |
| } |
| |
| void* JfrVirtualMemory::index_ptr(size_t index) { |
| assert((index * _aligned_datum_size_bytes) + _reserved_low < _commit_point, "invariant"); |
| return (void*)((index * _aligned_datum_size_bytes) + _reserved_low); |
| } |
| |
| void* JfrVirtualMemory::get(size_t index) { |
| return index_ptr(index); |
| } |
| |
| size_t JfrVirtualMemory::count() const { |
| return (_top - _reserved_low) / _aligned_datum_size_bytes; |
| } |
| |
| size_t JfrVirtualMemory::live_set() const { |
| return _top - _reserved_low; |
| } |
| |
| size_t JfrVirtualMemory::reserved_size() const { |
| return _reserved_high - _reserved_low; |
| } |
| |
| bool JfrVirtualMemory::compact(size_t index) { |
| assert(index > 0, "invariant"); |
| assert(index <= reserved_size(), "invariant"); |
| const u1* low = static_cast<u1*>(index_ptr(index)); |
| const size_t block_size = _top - low; |
| memcpy(const_cast<u1*>(_reserved_low), low, block_size); |
| _top = const_cast<u1*>(_reserved_low) + block_size; |
| assert(live_set() == block_size, "invariant"); |
| return true; |
| } |