1 /* 2 * Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP 26 #define SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP 27 28 #include "gc/shared/gcUtil.hpp" 29 #include "oops/typeArrayOop.hpp" 30 #include "runtime/perfData.hpp" 31 #include "runtime/vm_version.hpp" 32 33 class GlobalTLABStats; 34 35 // ThreadLocalAllocBuffer: a descriptor for thread-local storage used by 36 // the threads for allocation. 37 // It is thread-private at any time, but maybe multiplexed over 38 // time across multiple threads. The park()/unpark() pair is 39 // used to make it available for such multiplexing. 40 class ThreadLocalAllocBuffer: public CHeapObj<mtThread> { 41 friend class VMStructs; 42 friend class JVMCIVMStructs; 43 private: 44 HeapWord* _start; // address of TLAB 45 HeapWord* _top; // address after last allocation 46 HeapWord* _pf_top; // allocation prefetch watermark 47 HeapWord* _end; // allocation end (excluding alignment_reserve) 48 size_t _desired_size; // desired size (including alignment_reserve) 49 size_t _refill_waste_limit; // hold onto tlab if free() is larger than this 50 size_t _allocated_before_last_gc; // total bytes allocated up until the last gc 51 52 static size_t _max_size; // maximum size of any TLAB 53 static int _reserve_for_allocation_prefetch; // Reserve at the end of the TLAB 54 static unsigned _target_refills; // expected number of refills between GCs 55 56 unsigned _number_of_refills; 57 unsigned _fast_refill_waste; 58 unsigned _slow_refill_waste; 59 unsigned _gc_waste; 60 unsigned _slow_allocations; 61 size_t _allocated_size; 62 63 AdaptiveWeightedAverage _allocation_fraction; // fraction of eden allocated in tlabs 64 65 void accumulate_statistics(); 66 void initialize_statistics(); 67 68 void set_start(HeapWord* start) { _start = start; } 69 void set_end(HeapWord* end) { _end = end; } 70 void set_top(HeapWord* top) { _top = top; } 71 void set_pf_top(HeapWord* pf_top) { _pf_top = pf_top; } 72 void set_desired_size(size_t desired_size) { _desired_size = desired_size; } 73 void set_refill_waste_limit(size_t waste) { _refill_waste_limit = waste; } 74 75 size_t initial_refill_waste_limit() { return desired_size() / TLABRefillWasteFraction; } 76 77 static int target_refills() { return _target_refills; } 78 size_t initial_desired_size(); 79 80 size_t remaining() const { return end() == NULL ? 0 : pointer_delta(hard_end(), top()); } 81 82 // Make parsable and release it. 83 void reset(); 84 85 // Resize based on amount of allocation, etc. 86 void resize(); 87 88 void invariants() const { assert(top() >= start() && top() <= end(), "invalid tlab"); } 89 90 void initialize(HeapWord* start, HeapWord* top, HeapWord* end); 91 92 void print_stats(const char* tag); 93 94 Thread* myThread(); 95 96 // statistics 97 98 int number_of_refills() const { return _number_of_refills; } 99 int fast_refill_waste() const { return _fast_refill_waste; } 100 int slow_refill_waste() const { return _slow_refill_waste; } 101 int gc_waste() const { return _gc_waste; } 102 int slow_allocations() const { return _slow_allocations; } 103 104 static GlobalTLABStats* _global_stats; 105 static GlobalTLABStats* global_stats() { return _global_stats; } 106 107 public: 108 ThreadLocalAllocBuffer() : _allocation_fraction(TLABAllocationWeight), _allocated_before_last_gc(0) { 109 // do nothing. tlabs must be inited by initialize() calls 110 } 111 112 static size_t min_size() { return align_object_size(MinTLABSize / HeapWordSize) + alignment_reserve(); } 113 static size_t max_size() { assert(_max_size != 0, "max_size not set up"); return _max_size; } 114 static size_t max_size_in_bytes() { return max_size() * BytesPerWord; } 115 static void set_max_size(size_t max_size) { _max_size = max_size; } 116 117 HeapWord* start() const { return _start; } 118 HeapWord* end() const { return _end; } 119 HeapWord* hard_end() const { return _end + alignment_reserve(); } 120 HeapWord* top() const { return _top; } 121 HeapWord* pf_top() const { return _pf_top; } 122 size_t desired_size() const { return _desired_size; } 123 size_t used() const { return pointer_delta(top(), start()); } 124 size_t used_bytes() const { return pointer_delta(top(), start(), 1); } 125 size_t free() const { return pointer_delta(end(), top()); } 126 // Don't discard tlab if remaining space is larger than this. 127 size_t refill_waste_limit() const { return _refill_waste_limit; } 128 129 // Allocate size HeapWords. The memory is NOT initialized to zero. 130 inline HeapWord* allocate(size_t size); 131 132 // Reserve space at the end of TLAB 133 static size_t end_reserve() { 134 int reserve_size = typeArrayOopDesc::header_size(T_INT); 135 return MAX2(reserve_size, _reserve_for_allocation_prefetch); 136 } 137 static size_t alignment_reserve() { return align_object_size(end_reserve()); } 138 static size_t alignment_reserve_in_bytes() { return alignment_reserve() * HeapWordSize; } 139 140 // Return tlab size or remaining space in eden such that the 141 // space is large enough to hold obj_size and necessary fill space. 142 // Otherwise return 0; 143 inline size_t compute_size(size_t obj_size); 144 145 // Compute the minimal needed tlab size for the given object size. 146 static inline size_t compute_min_size(size_t obj_size); 147 148 // Record slow allocation 149 inline void record_slow_allocation(size_t obj_size); 150 151 // Initialization at startup 152 static void startup_initialization(); 153 154 // Make an in-use tlab parsable, optionally retiring and/or zapping it. 155 void make_parsable(bool retire, bool zap = true); 156 157 // Retire in-use tlab before allocation of a new tlab 158 void clear_before_allocation(); 159 160 // Accumulate statistics across all tlabs before gc 161 static void accumulate_statistics_before_gc(); 162 163 // Resize tlabs for all threads 164 static void resize_all_tlabs(); 165 166 void fill(HeapWord* start, HeapWord* top, size_t new_size); 167 void initialize(); 168 169 static size_t refill_waste_limit_increment() { return TLABWasteIncrement; } 170 171 template <typename T> void addresses_do(T f) { 172 f(&_start); 173 f(&_top); 174 f(&_pf_top); 175 f(&_end); 176 } 177 178 // Code generation support 179 static ByteSize start_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _start); } 180 static ByteSize end_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _end ); } 181 static ByteSize top_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _top ); } 182 static ByteSize pf_top_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _pf_top ); } 183 static ByteSize size_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _desired_size ); } 184 static ByteSize refill_waste_limit_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _refill_waste_limit ); } 185 186 static ByteSize number_of_refills_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _number_of_refills ); } 187 static ByteSize fast_refill_waste_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _fast_refill_waste ); } 188 static ByteSize slow_allocations_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _slow_allocations ); } 189 190 void verify(); 191 }; 192 193 class GlobalTLABStats: public CHeapObj<mtThread> { 194 private: 195 196 // Accumulate perfdata in private variables because 197 // PerfData should be write-only for security reasons 198 // (see perfData.hpp) 199 unsigned _allocating_threads; 200 unsigned _total_refills; 201 unsigned _max_refills; 202 size_t _total_allocation; 203 size_t _total_gc_waste; 204 size_t _max_gc_waste; 205 size_t _total_slow_refill_waste; 206 size_t _max_slow_refill_waste; 207 size_t _total_fast_refill_waste; 208 size_t _max_fast_refill_waste; 209 unsigned _total_slow_allocations; 210 unsigned _max_slow_allocations; 211 212 PerfVariable* _perf_allocating_threads; 213 PerfVariable* _perf_total_refills; 214 PerfVariable* _perf_max_refills; 215 PerfVariable* _perf_allocation; 216 PerfVariable* _perf_gc_waste; 217 PerfVariable* _perf_max_gc_waste; 218 PerfVariable* _perf_slow_refill_waste; 219 PerfVariable* _perf_max_slow_refill_waste; 220 PerfVariable* _perf_fast_refill_waste; 221 PerfVariable* _perf_max_fast_refill_waste; 222 PerfVariable* _perf_slow_allocations; 223 PerfVariable* _perf_max_slow_allocations; 224 225 AdaptiveWeightedAverage _allocating_threads_avg; 226 227 public: 228 GlobalTLABStats(); 229 230 // Initialize all counters 231 void initialize(); 232 233 // Write all perf counters to the perf_counters 234 void publish(); 235 236 void print(); 237 238 // Accessors 239 unsigned allocating_threads_avg() { 240 return MAX2((unsigned)(_allocating_threads_avg.average() + 0.5), 1U); 241 } 242 243 size_t allocation() { 244 return _total_allocation; 245 } 246 247 // Update methods 248 249 void update_allocating_threads() { 250 _allocating_threads++; 251 } 252 void update_number_of_refills(unsigned value) { 253 _total_refills += value; 254 _max_refills = MAX2(_max_refills, value); 255 } 256 void update_allocation(size_t value) { 257 _total_allocation += value; 258 } 259 void update_gc_waste(size_t value) { 260 _total_gc_waste += value; 261 _max_gc_waste = MAX2(_max_gc_waste, value); 262 } 263 void update_fast_refill_waste(size_t value) { 264 _total_fast_refill_waste += value; 265 _max_fast_refill_waste = MAX2(_max_fast_refill_waste, value); 266 } 267 void update_slow_refill_waste(size_t value) { 268 _total_slow_refill_waste += value; 269 _max_slow_refill_waste = MAX2(_max_slow_refill_waste, value); 270 } 271 void update_slow_allocations(unsigned value) { 272 _total_slow_allocations += value; 273 _max_slow_allocations = MAX2(_max_slow_allocations, value); 274 } 275 }; 276 277 #endif // SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP