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src/hotspot/share/memory/metaspace/virtualSpaceNode.cpp
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rev 60538 : imported patch jep387-all.patch
*** 1,7 ****
/*
! * Copyright (c) 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.
--- 1,8 ----
/*
! * Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved.
! * Copyright (c) 2018, 2020 SAP SE. 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.
*** 23,588 ****
*/
#include "precompiled.hpp"
#include "logging/log.hpp"
! #include "logging/logStream.hpp"
#include "memory/metaspace/metachunk.hpp"
- #include "memory/metaspace.hpp"
- #include "memory/metaspace/chunkManager.hpp"
- #include "memory/metaspace/metaDebug.hpp"
#include "memory/metaspace/metaspaceCommon.hpp"
! #include "memory/metaspace/occupancyMap.hpp"
#include "memory/metaspace/virtualSpaceNode.hpp"
! #include "memory/virtualspace.hpp"
! #include "runtime/atomic.hpp"
#include "runtime/os.hpp"
! #include "services/memTracker.hpp"
! #include "utilities/copy.hpp"
#include "utilities/debug.hpp"
#include "utilities/globalDefinitions.hpp"
namespace metaspace {
! // Decide if large pages should be committed when the memory is reserved.
! static bool should_commit_large_pages_when_reserving(size_t bytes) {
! if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) {
! size_t words = bytes / BytesPerWord;
! bool is_class = false; // We never reserve large pages for the class space.
! if (MetaspaceGC::can_expand(words, is_class) &&
! MetaspaceGC::allowed_expansion() >= words) {
! return true;
! }
! }
! return false;
}
! // byte_size is the size of the associated virtualspace.
! VirtualSpaceNode::VirtualSpaceNode(bool is_class, size_t bytes) :
! _next(NULL), _is_class(is_class), _rs(), _top(NULL), _container_count(0), _occupancy_map(NULL) {
! assert_is_aligned(bytes, Metaspace::reserve_alignment());
! bool large_pages = should_commit_large_pages_when_reserving(bytes);
! _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages);
!
! if (_rs.is_reserved()) {
! assert(_rs.base() != NULL, "Catch if we get a NULL address");
! assert(_rs.size() != 0, "Catch if we get a 0 size");
! assert_is_aligned(_rs.base(), Metaspace::reserve_alignment());
! assert_is_aligned(_rs.size(), Metaspace::reserve_alignment());
!
! MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass);
! }
! }
!
! void VirtualSpaceNode::purge(ChunkManager* chunk_manager) {
! // When a node is purged, lets give it a thorough examination.
! DEBUG_ONLY(verify(true);)
! Metachunk* chunk = first_chunk();
! Metachunk* invalid_chunk = (Metachunk*) top();
! while (chunk < invalid_chunk ) {
! assert(chunk->is_tagged_free(), "Should be tagged free");
! MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
! chunk_manager->remove_chunk(chunk);
! chunk->remove_sentinel();
! assert(chunk->next() == NULL &&
! chunk->prev() == NULL,
! "Was not removed from its list");
! chunk = (Metachunk*) next;
! }
! }
!
! void VirtualSpaceNode::print_map(outputStream* st, bool is_class) const {
!
! if (bottom() == top()) {
! return;
! }
!
! const size_t spec_chunk_size = is_class ? ClassSpecializedChunk : SpecializedChunk;
! const size_t small_chunk_size = is_class ? ClassSmallChunk : SmallChunk;
! const size_t med_chunk_size = is_class ? ClassMediumChunk : MediumChunk;
!
! int line_len = 100;
! const size_t section_len = align_up(spec_chunk_size * line_len, med_chunk_size);
! line_len = (int)(section_len / spec_chunk_size);
!
! static const int NUM_LINES = 4;
!
! char* lines[NUM_LINES];
! for (int i = 0; i < NUM_LINES; i ++) {
! lines[i] = (char*)os::malloc(line_len, mtInternal);
! }
! int pos = 0;
! const MetaWord* p = bottom();
! const Metachunk* chunk = (const Metachunk*)p;
! const MetaWord* chunk_end = p + chunk->word_size();
! while (p < top()) {
! if (pos == line_len) {
! pos = 0;
! for (int i = 0; i < NUM_LINES; i ++) {
! st->fill_to(22);
! st->print_raw(lines[i], line_len);
! st->cr();
! }
! }
! if (pos == 0) {
! st->print(PTR_FORMAT ":", p2i(p));
}
! if (p == chunk_end) {
! chunk = (Metachunk*)p;
! chunk_end = p + chunk->word_size();
! }
! // line 1: chunk starting points (a dot if that area is a chunk start).
! lines[0][pos] = p == (const MetaWord*)chunk ? '.' : ' ';
!
! // Line 2: chunk type (x=spec, s=small, m=medium, h=humongous), uppercase if
! // chunk is in use.
! const bool chunk_is_free = ((Metachunk*)chunk)->is_tagged_free();
! if (chunk->word_size() == spec_chunk_size) {
! lines[1][pos] = chunk_is_free ? 'x' : 'X';
! } else if (chunk->word_size() == small_chunk_size) {
! lines[1][pos] = chunk_is_free ? 's' : 'S';
! } else if (chunk->word_size() == med_chunk_size) {
! lines[1][pos] = chunk_is_free ? 'm' : 'M';
! } else if (chunk->word_size() > med_chunk_size) {
! lines[1][pos] = chunk_is_free ? 'h' : 'H';
! } else {
! ShouldNotReachHere();
! }
!
! // Line 3: chunk origin
! const ChunkOrigin origin = chunk->get_origin();
! lines[2][pos] = origin == origin_normal ? ' ' : '0' + (int) origin;
!
! // Line 4: Virgin chunk? Virgin chunks are chunks created as a byproduct of padding or splitting,
! // but were never used.
! lines[3][pos] = chunk->get_use_count() > 0 ? ' ' : 'v';
!
! p += spec_chunk_size;
! pos ++;
! }
! if (pos > 0) {
! for (int i = 0; i < NUM_LINES; i ++) {
! st->fill_to(22);
! st->print_raw(lines[i], line_len);
! st->cr();
}
}
! for (int i = 0; i < NUM_LINES; i ++) {
! os::free(lines[i]);
}
- }
! #ifdef ASSERT
! // Verify counters, all chunks in this list node and the occupancy map.
! void VirtualSpaceNode::verify(bool slow) {
! log_trace(gc, metaspace, freelist)("verifying %s virtual space node (%s).",
! (is_class() ? "class space" : "metaspace"), (slow ? "slow" : "quick"));
! // Fast mode: just verify chunk counters and basic geometry
! // Slow mode: verify chunks and occupancy map
! uintx num_in_use_chunks = 0;
! Metachunk* chunk = first_chunk();
! Metachunk* invalid_chunk = (Metachunk*) top();
!
! // Iterate the chunks in this node and verify each chunk.
! while (chunk < invalid_chunk ) {
! if (slow) {
! do_verify_chunk(chunk);
! }
! if (!chunk->is_tagged_free()) {
! num_in_use_chunks ++;
! }
! const size_t s = chunk->word_size();
! // Prevent endless loop on invalid chunk size.
! assert(is_valid_chunksize(is_class(), s), "Invalid chunk size: " SIZE_FORMAT ".", s);
! MetaWord* next = ((MetaWord*)chunk) + s;
! chunk = (Metachunk*) next;
! }
! assert(_container_count == num_in_use_chunks, "Container count mismatch (real: " UINTX_FORMAT
! ", counter: " UINTX_FORMAT ".", num_in_use_chunks, _container_count);
! // Also verify the occupancy map.
! if (slow) {
! occupancy_map()->verify(bottom(), top());
! }
! }
!
! // Verify that all free chunks in this node are ideally merged
! // (there not should be multiple small chunks where a large chunk could exist.)
! void VirtualSpaceNode::verify_free_chunks_are_ideally_merged() {
! Metachunk* chunk = first_chunk();
! Metachunk* invalid_chunk = (Metachunk*) top();
! // Shorthands.
! const size_t size_med = (is_class() ? ClassMediumChunk : MediumChunk) * BytesPerWord;
! const size_t size_small = (is_class() ? ClassSmallChunk : SmallChunk) * BytesPerWord;
! int num_free_chunks_since_last_med_boundary = -1;
! int num_free_chunks_since_last_small_boundary = -1;
! bool error = false;
! char err[256];
! while (!error && chunk < invalid_chunk ) {
! // Test for missed chunk merge opportunities: count number of free chunks since last chunk boundary.
! // Reset the counter when encountering a non-free chunk.
! if (chunk->get_chunk_type() != HumongousIndex) {
! if (chunk->is_tagged_free()) {
! // Count successive free, non-humongous chunks.
! if (is_aligned(chunk, size_small)) {
! if (num_free_chunks_since_last_small_boundary > 0) {
! error = true;
! jio_snprintf(err, sizeof(err), "Missed chunk merge opportunity to merge a small chunk preceding " PTR_FORMAT ".", p2i(chunk));
! } else {
! num_free_chunks_since_last_small_boundary = 0;
! }
! } else if (num_free_chunks_since_last_small_boundary != -1) {
! num_free_chunks_since_last_small_boundary ++;
! }
! if (is_aligned(chunk, size_med)) {
! if (num_free_chunks_since_last_med_boundary > 0) {
! error = true;
! jio_snprintf(err, sizeof(err), "Missed chunk merge opportunity to merge a medium chunk preceding " PTR_FORMAT ".", p2i(chunk));
! } else {
! num_free_chunks_since_last_med_boundary = 0;
! }
! } else if (num_free_chunks_since_last_med_boundary != -1) {
! num_free_chunks_since_last_med_boundary ++;
! }
! } else {
! // Encountering a non-free chunk, reset counters.
! num_free_chunks_since_last_med_boundary = -1;
! num_free_chunks_since_last_small_boundary = -1;
! }
! } else {
! // One cannot merge areas with a humongous chunk in the middle. Reset counters.
! num_free_chunks_since_last_med_boundary = -1;
! num_free_chunks_since_last_small_boundary = -1;
! }
!
! if (error) {
! print_map(tty, is_class());
! fatal("%s", err);
! }
! MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
! chunk = (Metachunk*) next;
}
}
- #endif // ASSERT
! void VirtualSpaceNode::inc_container_count() {
assert_lock_strong(MetaspaceExpand_lock);
! _container_count++;
}
! void VirtualSpaceNode::dec_container_count() {
assert_lock_strong(MetaspaceExpand_lock);
- _container_count--;
- }
! VirtualSpaceNode::~VirtualSpaceNode() {
! _rs.release();
! if (_occupancy_map != NULL) {
! delete _occupancy_map;
}
#ifdef ASSERT
! size_t word_size = sizeof(*this) / BytesPerWord;
! Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1);
#endif
}
! size_t VirtualSpaceNode::used_words_in_vs() const {
! return pointer_delta(top(), bottom(), sizeof(MetaWord));
}
- // Space committed in the VirtualSpace
- size_t VirtualSpaceNode::capacity_words_in_vs() const {
- return pointer_delta(end(), bottom(), sizeof(MetaWord));
- }
-
- size_t VirtualSpaceNode::free_words_in_vs() const {
- return pointer_delta(end(), top(), sizeof(MetaWord));
- }
-
- // Given an address larger than top(), allocate padding chunks until top is at the given address.
- void VirtualSpaceNode::allocate_padding_chunks_until_top_is_at(MetaWord* target_top) {
-
- assert(target_top > top(), "Sanity");
-
- // Padding chunks are added to the freelist.
- ChunkManager* const chunk_manager = Metaspace::get_chunk_manager(is_class());
-
- // shorthands
- const size_t spec_word_size = chunk_manager->specialized_chunk_word_size();
- const size_t small_word_size = chunk_manager->small_chunk_word_size();
- const size_t med_word_size = chunk_manager->medium_chunk_word_size();
-
- while (top() < target_top) {
-
- // We could make this coding more generic, but right now we only deal with two possible chunk sizes
- // for padding chunks, so it is not worth it.
- size_t padding_chunk_word_size = small_word_size;
- if (is_aligned(top(), small_word_size * sizeof(MetaWord)) == false) {
- assert_is_aligned(top(), spec_word_size * sizeof(MetaWord)); // Should always hold true.
- padding_chunk_word_size = spec_word_size;
- }
- MetaWord* here = top();
- assert_is_aligned(here, padding_chunk_word_size * sizeof(MetaWord));
- inc_top(padding_chunk_word_size);
-
- // Create new padding chunk.
- ChunkIndex padding_chunk_type = get_chunk_type_by_size(padding_chunk_word_size, is_class());
- assert(padding_chunk_type == SpecializedIndex || padding_chunk_type == SmallIndex, "sanity");
-
- Metachunk* const padding_chunk =
- ::new (here) Metachunk(padding_chunk_type, is_class(), padding_chunk_word_size, this);
- assert(padding_chunk == (Metachunk*)here, "Sanity");
- DEBUG_ONLY(padding_chunk->set_origin(origin_pad);)
- log_trace(gc, metaspace, freelist)("Created padding chunk in %s at "
- PTR_FORMAT ", size " SIZE_FORMAT_HEX ".",
- (is_class() ? "class space " : "metaspace"),
- p2i(padding_chunk), padding_chunk->word_size() * sizeof(MetaWord));
-
- // Mark chunk start in occupancy map.
- occupancy_map()->set_chunk_starts_at_address((MetaWord*)padding_chunk, true);
-
- // Chunks are born as in-use (see MetaChunk ctor). So, before returning
- // the padding chunk to its chunk manager, mark it as in use (ChunkManager
- // will assert that).
- do_update_in_use_info_for_chunk(padding_chunk, true);
-
- // Return Chunk to freelist.
- inc_container_count();
- chunk_manager->return_single_chunk(padding_chunk);
- // Please note: at this point, ChunkManager::return_single_chunk()
- // may already have merged the padding chunk with neighboring chunks, so
- // it may have vanished at this point. Do not reference the padding
- // chunk beyond this point.
- }
-
- assert(top() == target_top, "Sanity");
-
- } // allocate_padding_chunks_until_top_is_at()
-
- // Allocates the chunk from the virtual space only.
- // This interface is also used internally for debugging. Not all
- // chunks removed here are necessarily used for allocation.
- Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
- // Non-humongous chunks are to be allocated aligned to their chunk
- // size. So, start addresses of medium chunks are aligned to medium
- // chunk size, those of small chunks to small chunk size and so
- // forth. This facilitates merging of free chunks and reduces
- // fragmentation. Chunk sizes are spec < small < medium, with each
- // larger chunk size being a multiple of the next smaller chunk
- // size.
- // Because of this alignment, me may need to create a number of padding
- // chunks. These chunks are created and added to the freelist.
-
- // The chunk manager to which we will give our padding chunks.
- ChunkManager* const chunk_manager = Metaspace::get_chunk_manager(is_class());
-
- // shorthands
- const size_t spec_word_size = chunk_manager->specialized_chunk_word_size();
- const size_t small_word_size = chunk_manager->small_chunk_word_size();
- const size_t med_word_size = chunk_manager->medium_chunk_word_size();
-
- assert(chunk_word_size == spec_word_size || chunk_word_size == small_word_size ||
- chunk_word_size >= med_word_size, "Invalid chunk size requested.");
-
- // Chunk alignment (in bytes) == chunk size unless humongous.
- // Humongous chunks are aligned to the smallest chunk size (spec).
- const size_t required_chunk_alignment = (chunk_word_size > med_word_size ?
- spec_word_size : chunk_word_size) * sizeof(MetaWord);
-
- // Do we have enough space to create the requested chunk plus
- // any padding chunks needed?
- MetaWord* const next_aligned =
- static_cast<MetaWord*>(align_up(top(), required_chunk_alignment));
- if (!is_available((next_aligned - top()) + chunk_word_size)) {
- return NULL;
- }
-
- // Before allocating the requested chunk, allocate padding chunks if necessary.
- // We only need to do this for small or medium chunks: specialized chunks are the
- // smallest size, hence always aligned. Homungous chunks are allocated unaligned
- // (implicitly, also aligned to smallest chunk size).
- if ((chunk_word_size == med_word_size || chunk_word_size == small_word_size) && next_aligned > top()) {
- log_trace(gc, metaspace, freelist)("Creating padding chunks in %s between %p and %p...",
- (is_class() ? "class space " : "metaspace"),
- top(), next_aligned);
- allocate_padding_chunks_until_top_is_at(next_aligned);
- // Now, top should be aligned correctly.
- assert_is_aligned(top(), required_chunk_alignment);
- }
-
- // Now, top should be aligned correctly.
- assert_is_aligned(top(), required_chunk_alignment);
-
- // Bottom of the new chunk
- MetaWord* chunk_limit = top();
- assert(chunk_limit != NULL, "Not safe to call this method");
-
- // 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_space.committed_size() == _virtual_space.actual_committed_size(),
- "The committed memory doesn't match the expanded memory.");
-
- if (!is_available(chunk_word_size)) {
- LogTarget(Trace, gc, metaspace, freelist) lt;
- if (lt.is_enabled()) {
- LogStream ls(lt);
- ls.print("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size);
- // Dump some information about the virtual space that is nearly full
- print_on(&ls);
- }
- return NULL;
- }
-
- // Take the space (bump top on the current virtual space).
- inc_top(chunk_word_size);
-
- // Initialize the chunk
- ChunkIndex chunk_type = get_chunk_type_by_size(chunk_word_size, is_class());
- Metachunk* result = ::new (chunk_limit) Metachunk(chunk_type, is_class(), chunk_word_size, this);
- assert(result == (Metachunk*)chunk_limit, "Sanity");
- occupancy_map()->set_chunk_starts_at_address((MetaWord*)result, true);
- do_update_in_use_info_for_chunk(result, true);
! inc_container_count();
! #ifdef ASSERT
! EVERY_NTH(VerifyMetaspaceInterval)
! chunk_manager->locked_verify(true);
! verify(true);
! END_EVERY_NTH
! do_verify_chunk(result);
! #endif
! result->inc_use_count();
- return result;
}
! // Expand the virtual space (commit more of the reserved space)
! bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) {
! size_t min_bytes = min_words * BytesPerWord;
! size_t preferred_bytes = preferred_words * BytesPerWord;
! size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size();
! if (uncommitted < min_bytes) {
! return false;
}
! size_t commit = MIN2(preferred_bytes, uncommitted);
! bool result = virtual_space()->expand_by(commit, false);
- if (result) {
- log_trace(gc, metaspace, freelist)("Expanded %s virtual space list node by " SIZE_FORMAT " words.",
- (is_class() ? "class" : "non-class"), commit);
- DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_committed_space_expanded));
- } else {
- log_trace(gc, metaspace, freelist)("Failed to expand %s virtual space list node by " SIZE_FORMAT " words.",
- (is_class() ? "class" : "non-class"), commit);
}
! assert(result, "Failed to commit memory");
- return result;
}
! Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
assert_lock_strong(MetaspaceExpand_lock);
! Metachunk* result = take_from_committed(chunk_word_size);
! return result;
}
! bool VirtualSpaceNode::initialize() {
! if (!_rs.is_reserved()) {
! return false;
}
! // These are necessary restriction to make sure that the virtual space always
! // grows in steps of Metaspace::commit_alignment(). If both base and size are
! // aligned only the middle alignment of the VirtualSpace is used.
! assert_is_aligned(_rs.base(), Metaspace::commit_alignment());
! assert_is_aligned(_rs.size(), Metaspace::commit_alignment());
! // 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.
! size_t pre_committed_size = _rs.special() ? _rs.size() : 0;
! bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size,
! Metaspace::commit_alignment());
! if (result) {
! assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(),
! "Checking that the pre-committed memory was registered by the VirtualSpace");
! set_top((MetaWord*)virtual_space()->low());
}
! // Initialize Occupancy Map.
! const size_t smallest_chunk_size = is_class() ? ClassSpecializedChunk : SpecializedChunk;
! _occupancy_map = new OccupancyMap(bottom(), reserved_words(), smallest_chunk_size);
- return result;
}
- void VirtualSpaceNode::print_on(outputStream* st, size_t scale) const {
- size_t used_words = used_words_in_vs();
- size_t commit_words = committed_words();
- size_t res_words = reserved_words();
- VirtualSpace* vs = virtual_space();
! st->print("node @" PTR_FORMAT ": ", p2i(this));
st->print("reserved=");
! print_scaled_words(st, res_words, scale);
st->print(", committed=");
! print_scaled_words_and_percentage(st, commit_words, res_words, scale);
st->print(", used=");
! print_scaled_words_and_percentage(st, used_words, res_words, scale);
st->cr();
! st->print(" [" PTR_FORMAT ", " PTR_FORMAT ", "
! PTR_FORMAT ", " PTR_FORMAT ")",
! p2i(bottom()), p2i(top()), p2i(end()),
! p2i(vs->high_boundary()));
}
! #ifdef ASSERT
! void VirtualSpaceNode::mangle() {
! size_t word_size = capacity_words_in_vs();
! Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
}
- #endif // ASSERT
- void VirtualSpaceNode::retire(ChunkManager* chunk_manager) {
- assert(is_class() == chunk_manager->is_class(), "Wrong ChunkManager?");
#ifdef ASSERT
! verify(false);
! EVERY_NTH(VerifyMetaspaceInterval)
! verify(true);
! END_EVERY_NTH
! #endif
! for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) {
! ChunkIndex index = (ChunkIndex)i;
! size_t chunk_size = chunk_manager->size_by_index(index);
!
! while (free_words_in_vs() >= chunk_size) {
! Metachunk* chunk = get_chunk_vs(chunk_size);
! // Chunk will be allocated aligned, so allocation may require
! // additional padding chunks. That may cause above allocation to
! // fail. Just ignore the failed allocation and continue with the
! // next smaller chunk size. As the VirtualSpaceNode comitted
! // size should be a multiple of the smallest chunk size, we
! // should always be able to fill the VirtualSpace completely.
! if (chunk == NULL) {
! break;
! }
! chunk_manager->return_single_chunk(chunk);
! }
! }
! assert(free_words_in_vs() == 0, "should be empty now");
}
} // namespace metaspace
--- 24,520 ----
*/
#include "precompiled.hpp"
#include "logging/log.hpp"
!
! #include "memory/metaspace/chunkLevel.hpp"
! #include "memory/metaspace/chunkHeaderPool.hpp"
! #include "memory/metaspace/commitLimiter.hpp"
! #include "memory/metaspace/counter.hpp"
! #include "memory/metaspace/freeChunkList.hpp"
! #include "memory/metaspace/internStat.hpp"
#include "memory/metaspace/metachunk.hpp"
#include "memory/metaspace/metaspaceCommon.hpp"
! #include "memory/metaspace/rootChunkArea.hpp"
! #include "memory/metaspace/runningCounters.hpp"
! #include "memory/metaspace/settings.hpp"
#include "memory/metaspace/virtualSpaceNode.hpp"
! #include "memory/metaspace.hpp"
!
! #include "runtime/globals.hpp"
! #include "runtime/mutexLocker.hpp"
#include "runtime/os.hpp"
!
! #include "utilities/align.hpp"
#include "utilities/debug.hpp"
#include "utilities/globalDefinitions.hpp"
+ #include "utilities/ostream.hpp"
namespace metaspace {
! #define LOGFMT "VsListNode @" PTR_FORMAT " base " PTR_FORMAT " "
! #define LOGFMT_ARGS p2i(this), p2i(_base)
! #ifdef ASSERT
! void check_pointer_is_aligned_to_commit_granule(const MetaWord* p) {
! assert(is_aligned(p, Settings::commit_granule_bytes()),
! "Pointer not aligned to commit granule size: " PTR_FORMAT ".",
! p2i(p));
! }
! void check_word_size_is_aligned_to_commit_granule(size_t word_size) {
! assert(is_aligned(word_size, Settings::commit_granule_words()),
! "Not aligned to commit granule size: " SIZE_FORMAT ".", word_size);
}
+ #endif
!
! // Given an address range, ensure it is committed.
! //
! // The range has to be aligned to granule size.
! //
! // Function will:
! // - check how many granules in that region are uncommitted; If all are committed, it
! // returns true immediately.
! // - check if committing those uncommitted granules would bring us over the commit limit
! // (GC threshold, MaxMetaspaceSize). If true, it returns false.
! // - commit the memory.
! // - mark the range as committed in the commit mask
! //
! // Returns true if success, false if it did hit a commit limit.
! bool VirtualSpaceNode::commit_range(MetaWord* p, size_t word_size) {
!
! DEBUG_ONLY(check_pointer_is_aligned_to_commit_granule(p);)
! DEBUG_ONLY(check_word_size_is_aligned_to_commit_granule(word_size);)
! assert_lock_strong(MetaspaceExpand_lock);
!
! // First calculate how large the committed regions in this range are
! const size_t committed_words_in_range = _commit_mask.get_committed_size_in_range(p, word_size);
! DEBUG_ONLY(check_word_size_is_aligned_to_commit_granule(committed_words_in_range);)
!
! // By how much words we would increase commit charge
! // were we to commit the given address range completely.
! const size_t commit_increase_words = word_size - committed_words_in_range;
!
! UL2(debug, "committing range " PTR_FORMAT ".." PTR_FORMAT "(" SIZE_FORMAT " words)",
! p2i(p), p2i(p + word_size), word_size);
!
! if (commit_increase_words == 0) {
! UL(debug, "... already fully committed.");
! return true; // Already fully committed, nothing to do.
}
!
! // Before committing any more memory, check limits.
! if (_commit_limiter->possible_expansion_words() < commit_increase_words) {
! UL(debug, "... cannot commit (limit).");
! return false;
}
+
+ // Commit...
+ if (os::commit_memory((char*)p, word_size * BytesPerWord, false) == false) {
+ vm_exit_out_of_memory(word_size * BytesPerWord, OOM_MMAP_ERROR, "Failed to commit metaspace.");
}
!
! if (AlwaysPreTouch) {
! os::pretouch_memory(p, p + word_size);
}
+ UL2(debug, "... committed " SIZE_FORMAT " additional words.", commit_increase_words);
! // ... tell commit limiter...
! _commit_limiter->increase_committed(commit_increase_words);
! // ... update counters in containing vslist ...
! _total_committed_words_counter->increment_by(commit_increase_words);
! // ... and update the commit mask.
! _commit_mask.mark_range_as_committed(p, word_size);
!
! #ifdef ASSERT
! // The commit boundary maintained in the CommitLimiter should be equal the sum of committed words
! // in both class and non-class vslist (outside gtests).
! if (_commit_limiter == CommitLimiter::globalLimiter()) {
! assert(_commit_limiter->committed_words() == RunningCounters::committed_words(), "counter mismatch");
}
+ #endif
+
+ InternalStats::inc_num_space_committed();
+
+ return true;
+
}
! // Given an address range, ensure it is committed.
! //
! // The range does not have to be aligned to granule size. However, the function will always commit
! // whole granules.
! //
! // Function will:
! // - check how many granules in that region are uncommitted; If all are committed, it
! // returns true immediately.
! // - check if committing those uncommitted granules would bring us over the commit limit
! // (GC threshold, MaxMetaspaceSize). If true, it returns false.
! // - commit the memory.
! // - mark the range as committed in the commit mask
! //
! // !! Careful:
! // calling ensure_range_is_committed on a range which contains both committed and uncommitted
! // areas will commit the whole area, thus erase the content in the existing committed parts.
! // Make sure you never call this on an address range containing live data. !!
! //
! // Returns true if success, false if it did hit a commit limit.
! bool VirtualSpaceNode::ensure_range_is_committed(MetaWord* p, size_t word_size) {
!
assert_lock_strong(MetaspaceExpand_lock);
! assert(p != NULL && word_size > 0, "Sanity");
!
! MetaWord* p_start = align_down(p, Settings::commit_granule_bytes());
! MetaWord* p_end = align_up(p + word_size, Settings::commit_granule_bytes());
!
! // Todo: simple for now. Make it more intelligent late
! return commit_range(p_start, p_end - p_start);
!
}
! // Given an address range (which has to be aligned to commit granule size):
! // - uncommit it
! // - mark it as uncommitted in the commit mask
! void VirtualSpaceNode::uncommit_range(MetaWord* p, size_t word_size) {
!
! DEBUG_ONLY(check_pointer_is_aligned_to_commit_granule(p);)
! DEBUG_ONLY(check_word_size_is_aligned_to_commit_granule(word_size);)
assert_lock_strong(MetaspaceExpand_lock);
! // First calculate how large the committed regions in this range are
! const size_t committed_words_in_range = _commit_mask.get_committed_size_in_range(p, word_size);
! DEBUG_ONLY(check_word_size_is_aligned_to_commit_granule(committed_words_in_range);)
!
! UL2(debug, "uncommitting range " PTR_FORMAT ".." PTR_FORMAT "(" SIZE_FORMAT " words)",
! p2i(p), p2i(p + word_size), word_size);
!
! if (committed_words_in_range == 0) {
! UL(debug, "... already fully uncommitted.");
! return; // Already fully uncommitted, nothing to do.
}
+
+ // Uncommit...
+ if (os::uncommit_memory((char*)p, word_size * BytesPerWord) == false) {
+ // Note: this can actually happen, since uncommit may increase the number of mappings.
+ fatal("Failed to uncommit metaspace.");
+ }
+
+ UL2(debug, "... uncommitted " SIZE_FORMAT " words.", committed_words_in_range);
+
+ // ... tell commit limiter...
+ _commit_limiter->decrease_committed(committed_words_in_range);
+
+ // ... and global counters...
+ _total_committed_words_counter->decrement_by(committed_words_in_range);
+
+ // ... and update the commit mask.
+ _commit_mask.mark_range_as_uncommitted(p, word_size);
+
#ifdef ASSERT
! // The commit boundary maintained in the CommitLimiter should be equal the sum of committed words
! // in both class and non-class vslist (outside gtests).
! if (_commit_limiter == CommitLimiter::globalLimiter()) { // We are outside a test scenario
! assert(_commit_limiter->committed_words() == RunningCounters::committed_words(), "counter mismatch");
! }
#endif
+
+ InternalStats::inc_num_space_uncommitted();
+
}
! //// creation, destruction ////
!
! VirtualSpaceNode::VirtualSpaceNode(ReservedSpace rs, bool owns_rs, CommitLimiter* limiter,
! SizeCounter* reserve_counter, SizeCounter* commit_counter)
! : _next(NULL),
! _rs(rs),
! _owns_rs(owns_rs),
! _base((MetaWord*)rs.base()),
! _word_size(rs.size() / BytesPerWord),
! _used_words(0),
! _commit_mask((MetaWord*)rs.base(), rs.size() / BytesPerWord),
! _root_chunk_area_lut((MetaWord*)rs.base(), rs.size() / BytesPerWord),
! _commit_limiter(limiter),
! _total_reserved_words_counter(reserve_counter),
! _total_committed_words_counter(commit_counter)
! {
! UL2(debug, "born (word_size " SIZE_FORMAT ").", _word_size);
!
! // Update reserved counter in vslist
! _total_reserved_words_counter->increment_by(_word_size);
!
! assert_is_aligned(_base, chunklevel::MAX_CHUNK_BYTE_SIZE);
! assert_is_aligned(_word_size, chunklevel::MAX_CHUNK_WORD_SIZE);
!
}
! // Create a node of a given size (it will create its own space).
! VirtualSpaceNode* VirtualSpaceNode::create_node(size_t word_size,
! CommitLimiter* limiter, SizeCounter* reserve_words_counter,
! SizeCounter* commit_words_counter)
! {
! DEBUG_ONLY(assert_is_aligned(word_size, chunklevel::MAX_CHUNK_WORD_SIZE);)
! ReservedSpace rs(word_size * BytesPerWord,
! Settings::virtual_space_node_reserve_alignment_words() * BytesPerWord,
! false // large
! );
!
! if (!rs.is_reserved()) {
! vm_exit_out_of_memory(word_size * BytesPerWord, OOM_MMAP_ERROR, "Failed to reserve memory for metaspace");
! }
!
! assert_is_aligned(rs.base(), chunklevel::MAX_CHUNK_BYTE_SIZE);
!
! InternalStats::inc_num_vsnodes_births();
! return new VirtualSpaceNode(rs, true, limiter, reserve_words_counter, commit_words_counter);
}
+ // Create a node over an existing space
+ VirtualSpaceNode* VirtualSpaceNode::create_node(ReservedSpace rs, CommitLimiter* limiter,
+ SizeCounter* reserve_words_counter, SizeCounter* commit_words_counter)
+ {
+ InternalStats::inc_num_vsnodes_births();
+ return new VirtualSpaceNode(rs, false, limiter, reserve_words_counter, commit_words_counter);
+ }
+
+ VirtualSpaceNode::~VirtualSpaceNode() {
! DEBUG_ONLY(verify_locked(true);)
! UL(debug, ": dies.");
! if (_owns_rs) {
! _rs.release();
}
! // Update counters in vslist
! size_t committed = committed_words();
! _total_committed_words_counter->decrement_by(committed);
! _total_reserved_words_counter->decrement_by(_word_size);
!
! // ... and tell commit limiter
! _commit_limiter->decrease_committed(committed);
!
! InternalStats::inc_num_vsnodes_deaths();
!
! }
!
! //// Chunk allocation, splitting, merging /////
!
! // Allocate a root chunk from this node. Will fail and return NULL if the node is full
! // - if we used up the whole address space of this node's memory region.
! // (in case this node backs compressed class space, this is how we hit
! // CompressedClassSpaceSize).
! // Note that this just returns reserved memory; caller must take care of committing this
! // chunk before using it.
! Metachunk* VirtualSpaceNode::allocate_root_chunk() {
!
! assert_lock_strong(MetaspaceExpand_lock);
!
! assert_is_aligned(free_words(), chunklevel::MAX_CHUNK_WORD_SIZE);
!
! if (free_words() >= chunklevel::MAX_CHUNK_WORD_SIZE) {
!
! MetaWord* loc = _base + _used_words;
! _used_words += chunklevel::MAX_CHUNK_WORD_SIZE;
!
! RootChunkArea* rca = _root_chunk_area_lut.get_area_by_address(loc);
!
! // Create a root chunk header and initialize it;
! Metachunk* c = rca->alloc_root_chunk_header(this);
!
! assert(c->base() == loc && c->vsnode() == this &&
! c->is_free(), "Sanity");
!
! DEBUG_ONLY(c->verify(true);)
!
! UL2(debug, "new root chunk " METACHUNK_FORMAT ".", METACHUNK_FORMAT_ARGS(c));
!
! return c;
}
! return NULL; // Node is full.
}
! // Given a chunk c, split it recursively until you get a chunk of the given target_level.
! //
! // The resulting target chunk resides at the same address as the original chunk.
! // The resulting splinters are added to freelists.
! void VirtualSpaceNode::split(chunklevel_t target_level, Metachunk* c, FreeChunkListVector* freelists) {
!
assert_lock_strong(MetaspaceExpand_lock);
!
! // Get the area associated with this chunk and let it handle the splitting
! RootChunkArea* rca = _root_chunk_area_lut.get_area_by_address(c->base());
!
! DEBUG_ONLY(rca->verify_area_is_ideally_merged();)
!
! rca->split(target_level, c, freelists);
!
}
! // Given a chunk, attempt to merge it recursively with its neighboring chunks.
! //
! // If successful (merged at least once), returns address of
! // the merged chunk; NULL otherwise.
! //
! // The merged chunks are removed from the freelists.
! //
! // !!! Please note that if this method returns a non-NULL value, the
! // original chunk will be invalid and should not be accessed anymore! !!!
! Metachunk* VirtualSpaceNode::merge(Metachunk* c, FreeChunkListVector* freelists) {
! assert(c != NULL && c->is_free(), "Sanity");
! assert_lock_strong(MetaspaceExpand_lock);
!
! // Get the rca associated with this chunk and let it handle the merging
! RootChunkArea* rca = _root_chunk_area_lut.get_area_by_address(c->base());
!
! Metachunk* c2 = rca->merge(c, freelists);
!
! DEBUG_ONLY(rca->verify_area_is_ideally_merged();)
!
! return c2;
!
! }
!
! // Given a chunk c, which must be "in use" and must not be a root chunk, attempt to
! // enlarge it in place by claiming its trailing buddy.
! //
! // This will only work if c is the leader of the buddy pair and the trailing buddy is free.
! //
! // If successful, the follower chunk will be removed from the freelists, the leader chunk c will
! // double in size (level decreased by one).
! //
! // On success, true is returned, false otherwise.
! bool VirtualSpaceNode::attempt_enlarge_chunk(Metachunk* c, FreeChunkListVector* freelists) {
!
! assert(c != NULL && c->is_in_use() && !c->is_root_chunk(), "Sanity");
! assert_lock_strong(MetaspaceExpand_lock);
!
! // Get the rca associated with this chunk and let it handle the merging
! RootChunkArea* rca = _root_chunk_area_lut.get_area_by_address(c->base());
!
! bool rc = rca->attempt_enlarge_chunk(c, freelists);
!
! DEBUG_ONLY(rca->verify_area_is_ideally_merged();)
!
! if (rc) {
! InternalStats::inc_num_chunks_enlarged();
}
! return rc;
! }
! // Attempts to purge the node:
! //
! // If all chunks living in this node are free, they will all be removed from
! // the freelist they currently reside in. Then, the node will be deleted.
! //
! // Returns true if the node has been deleted, false if not.
! // !! If this returns true, do not access the node from this point on. !!
! bool VirtualSpaceNode::attempt_purge(FreeChunkListVector* freelists) {
! assert_lock_strong(MetaspaceExpand_lock);
!
! if (!_owns_rs) {
! // We do not allow purging of nodes if we do not own the
! // underlying ReservedSpace (CompressClassSpace case).
! return false;
}
! // First find out if all areas are empty. Since empty chunks collapse to root chunk
! // size, if all chunks in this node are free root chunks we are good to go.
! if (!_root_chunk_area_lut.is_free()) {
! return false;
! }
!
! UL(debug, ": purging.");
!
! // Okay, we can purge. Before we can do this, we need to remove all chunks from the freelist.
! for (int narea = 0; narea < _root_chunk_area_lut.number_of_areas(); narea ++) {
! RootChunkArea* ra = _root_chunk_area_lut.get_area_by_index(narea);
! Metachunk* c = ra->first_chunk();
! if (c != NULL) {
! UL2(trace, "removing chunk from to-be-purged node: "
! METACHUNK_FULL_FORMAT ".", METACHUNK_FULL_FORMAT_ARGS(c));
! assert(c->is_free() && c->is_root_chunk(), "Sanity");
! freelists->remove(c);
! }
! }
!
! // Now, delete the node, then right away return since this object is invalid.
! delete this;
!
! return true;
}
! void VirtualSpaceNode::print_on(outputStream* st) const {
!
! size_t scale = K;
!
! st->print("base " PTR_FORMAT ": ", p2i(base()));
st->print("reserved=");
! print_scaled_words(st, word_size(), scale);
st->print(", committed=");
! print_scaled_words_and_percentage(st, committed_words(), word_size(), scale);
st->print(", used=");
! print_scaled_words_and_percentage(st, used_words(), word_size(), scale);
!
st->cr();
! _root_chunk_area_lut.print_on(st);
! _commit_mask.print_on(st);
!
}
! // Returns size, in words, of committed space in this node alone.
! // Note: iterates over commit mask and hence may be a tad expensive on large nodes.
! size_t VirtualSpaceNode::committed_words() const {
! return _commit_mask.get_committed_size();
}
#ifdef ASSERT
! void VirtualSpaceNode::verify(bool slow) const {
! MutexLocker fcl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag);
! verify_locked(slow);
}
+ // Verify counters and basic structure. Slow mode: verify all chunks in depth
+ void VirtualSpaceNode::verify_locked(bool slow) const {
+
+ assert_lock_strong(MetaspaceExpand_lock);
+
+ assert(base() != NULL, "Invalid base");
+ assert(base() == (MetaWord*)_rs.base() &&
+ word_size() == _rs.size() / BytesPerWord,
+ "Sanity");
+ assert_is_aligned(base(), chunklevel::MAX_CHUNK_BYTE_SIZE);
+ assert(used_words() <= word_size(), "Sanity");
+
+ // Since we only ever hand out root chunks from a vsnode, top should always be aligned
+ // to root chunk size.
+ assert_is_aligned(used_words(), chunklevel::MAX_CHUNK_WORD_SIZE);
+
+ _commit_mask.verify(slow);
+ assert(committed_words() <= word_size(), "Sanity");
+ assert_is_aligned(committed_words(), Settings::commit_granule_words());
+ _root_chunk_area_lut.verify(slow);
+
+ }
+
+ #endif
+
+
} // namespace metaspace
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