--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/shared/threadLocalAllocBuffer.hpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,266 @@
+/*
+ * Copyright (c) 1999, 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.
+ *
+ */
+
+#ifndef SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP
+#define SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP
+
+#include "gc/shared/gcUtil.hpp"
+#include "oops/typeArrayOop.hpp"
+#include "runtime/perfData.hpp"
+#include "runtime/vm_version.hpp"
+
+class GlobalTLABStats;
+
+// ThreadLocalAllocBuffer: a descriptor for thread-local storage used by
+// the threads for allocation.
+// It is thread-private at any time, but maybe multiplexed over
+// time across multiple threads. The park()/unpark() pair is
+// used to make it available for such multiplexing.
+class ThreadLocalAllocBuffer: public CHeapObj<mtThread> {
+ friend class VMStructs;
+ friend class JVMCIVMStructs;
+private:
+ HeapWord* _start; // address of TLAB
+ HeapWord* _top; // address after last allocation
+ HeapWord* _pf_top; // allocation prefetch watermark
+ HeapWord* _end; // allocation end (excluding alignment_reserve)
+ size_t _desired_size; // desired size (including alignment_reserve)
+ size_t _refill_waste_limit; // hold onto tlab if free() is larger than this
+ size_t _allocated_before_last_gc; // total bytes allocated up until the last gc
+
+ static size_t _max_size; // maximum size of any TLAB
+ static int _reserve_for_allocation_prefetch; // Reserve at the end of the TLAB
+ static unsigned _target_refills; // expected number of refills between GCs
+
+ unsigned _number_of_refills;
+ unsigned _fast_refill_waste;
+ unsigned _slow_refill_waste;
+ unsigned _gc_waste;
+ unsigned _slow_allocations;
+
+ AdaptiveWeightedAverage _allocation_fraction; // fraction of eden allocated in tlabs
+
+ void accumulate_statistics();
+ void initialize_statistics();
+
+ void set_start(HeapWord* start) { _start = start; }
+ void set_end(HeapWord* end) { _end = end; }
+ void set_top(HeapWord* top) { _top = top; }
+ void set_pf_top(HeapWord* pf_top) { _pf_top = pf_top; }
+ void set_desired_size(size_t desired_size) { _desired_size = desired_size; }
+ void set_refill_waste_limit(size_t waste) { _refill_waste_limit = waste; }
+
+ size_t initial_refill_waste_limit() { return desired_size() / TLABRefillWasteFraction; }
+
+ static int target_refills() { return _target_refills; }
+ size_t initial_desired_size();
+
+ size_t remaining() const { return end() == NULL ? 0 : pointer_delta(hard_end(), top()); }
+
+ // Make parsable and release it.
+ void reset();
+
+ // Resize based on amount of allocation, etc.
+ void resize();
+
+ void invariants() const { assert(top() >= start() && top() <= end(), "invalid tlab"); }
+
+ void initialize(HeapWord* start, HeapWord* top, HeapWord* end);
+
+ void print_stats(const char* tag);
+
+ Thread* myThread();
+
+ // statistics
+
+ int number_of_refills() const { return _number_of_refills; }
+ int fast_refill_waste() const { return _fast_refill_waste; }
+ int slow_refill_waste() const { return _slow_refill_waste; }
+ int gc_waste() const { return _gc_waste; }
+ int slow_allocations() const { return _slow_allocations; }
+
+ static GlobalTLABStats* _global_stats;
+ static GlobalTLABStats* global_stats() { return _global_stats; }
+
+public:
+ ThreadLocalAllocBuffer() : _allocation_fraction(TLABAllocationWeight), _allocated_before_last_gc(0) {
+ // do nothing. tlabs must be inited by initialize() calls
+ }
+
+ static size_t min_size() { return align_object_size(MinTLABSize / HeapWordSize) + alignment_reserve(); }
+ static size_t max_size() { assert(_max_size != 0, "max_size not set up"); return _max_size; }
+ static size_t max_size_in_bytes() { return max_size() * BytesPerWord; }
+ static void set_max_size(size_t max_size) { _max_size = max_size; }
+
+ HeapWord* start() const { return _start; }
+ HeapWord* end() const { return _end; }
+ HeapWord* hard_end() const { return _end + alignment_reserve(); }
+ HeapWord* top() const { return _top; }
+ HeapWord* pf_top() const { return _pf_top; }
+ size_t desired_size() const { return _desired_size; }
+ size_t used() const { return pointer_delta(top(), start()); }
+ size_t used_bytes() const { return pointer_delta(top(), start(), 1); }
+ size_t free() const { return pointer_delta(end(), top()); }
+ // Don't discard tlab if remaining space is larger than this.
+ size_t refill_waste_limit() const { return _refill_waste_limit; }
+
+ // Allocate size HeapWords. The memory is NOT initialized to zero.
+ inline HeapWord* allocate(size_t size);
+
+ // Reserve space at the end of TLAB
+ static size_t end_reserve() {
+ int reserve_size = typeArrayOopDesc::header_size(T_INT);
+ return MAX2(reserve_size, _reserve_for_allocation_prefetch);
+ }
+ static size_t alignment_reserve() { return align_object_size(end_reserve()); }
+ static size_t alignment_reserve_in_bytes() { return alignment_reserve() * HeapWordSize; }
+
+ // Return tlab size or remaining space in eden such that the
+ // space is large enough to hold obj_size and necessary fill space.
+ // Otherwise return 0;
+ inline size_t compute_size(size_t obj_size);
+
+ // Record slow allocation
+ inline void record_slow_allocation(size_t obj_size);
+
+ // Initialization at startup
+ static void startup_initialization();
+
+ // Make an in-use tlab parsable, optionally retiring and/or zapping it.
+ void make_parsable(bool retire, bool zap = true);
+
+ // Retire in-use tlab before allocation of a new tlab
+ void clear_before_allocation();
+
+ // Accumulate statistics across all tlabs before gc
+ static void accumulate_statistics_before_gc();
+
+ // Resize tlabs for all threads
+ static void resize_all_tlabs();
+
+ void fill(HeapWord* start, HeapWord* top, size_t new_size);
+ void initialize();
+
+ static size_t refill_waste_limit_increment() { return TLABWasteIncrement; }
+
+ // Code generation support
+ static ByteSize start_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _start); }
+ static ByteSize end_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _end ); }
+ static ByteSize top_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _top ); }
+ static ByteSize pf_top_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _pf_top ); }
+ static ByteSize size_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _desired_size ); }
+ static ByteSize refill_waste_limit_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _refill_waste_limit ); }
+
+ static ByteSize number_of_refills_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _number_of_refills ); }
+ static ByteSize fast_refill_waste_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _fast_refill_waste ); }
+ static ByteSize slow_allocations_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _slow_allocations ); }
+
+ void verify();
+};
+
+class GlobalTLABStats: public CHeapObj<mtThread> {
+private:
+
+ // Accumulate perfdata in private variables because
+ // PerfData should be write-only for security reasons
+ // (see perfData.hpp)
+ unsigned _allocating_threads;
+ unsigned _total_refills;
+ unsigned _max_refills;
+ size_t _total_allocation;
+ size_t _total_gc_waste;
+ size_t _max_gc_waste;
+ size_t _total_slow_refill_waste;
+ size_t _max_slow_refill_waste;
+ size_t _total_fast_refill_waste;
+ size_t _max_fast_refill_waste;
+ unsigned _total_slow_allocations;
+ unsigned _max_slow_allocations;
+
+ PerfVariable* _perf_allocating_threads;
+ PerfVariable* _perf_total_refills;
+ PerfVariable* _perf_max_refills;
+ PerfVariable* _perf_allocation;
+ PerfVariable* _perf_gc_waste;
+ PerfVariable* _perf_max_gc_waste;
+ PerfVariable* _perf_slow_refill_waste;
+ PerfVariable* _perf_max_slow_refill_waste;
+ PerfVariable* _perf_fast_refill_waste;
+ PerfVariable* _perf_max_fast_refill_waste;
+ PerfVariable* _perf_slow_allocations;
+ PerfVariable* _perf_max_slow_allocations;
+
+ AdaptiveWeightedAverage _allocating_threads_avg;
+
+public:
+ GlobalTLABStats();
+
+ // Initialize all counters
+ void initialize();
+
+ // Write all perf counters to the perf_counters
+ void publish();
+
+ void print();
+
+ // Accessors
+ unsigned allocating_threads_avg() {
+ return MAX2((unsigned)(_allocating_threads_avg.average() + 0.5), 1U);
+ }
+
+ size_t allocation() {
+ return _total_allocation;
+ }
+
+ // Update methods
+
+ void update_allocating_threads() {
+ _allocating_threads++;
+ }
+ void update_number_of_refills(unsigned value) {
+ _total_refills += value;
+ _max_refills = MAX2(_max_refills, value);
+ }
+ void update_allocation(size_t value) {
+ _total_allocation += value;
+ }
+ void update_gc_waste(size_t value) {
+ _total_gc_waste += value;
+ _max_gc_waste = MAX2(_max_gc_waste, value);
+ }
+ void update_fast_refill_waste(size_t value) {
+ _total_fast_refill_waste += value;
+ _max_fast_refill_waste = MAX2(_max_fast_refill_waste, value);
+ }
+ void update_slow_refill_waste(size_t value) {
+ _total_slow_refill_waste += value;
+ _max_slow_refill_waste = MAX2(_max_slow_refill_waste, value);
+ }
+ void update_slow_allocations(unsigned value) {
+ _total_slow_allocations += value;
+ _max_slow_allocations = MAX2(_max_slow_allocations, value);
+ }
+};
+
+#endif // SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP