Fri, 15 Apr 2011 09:36:28 -0400
7032407: Crash in LinkResolver::runtime_resolve_virtual_method()
Summary: Make CDS reorder vtables so that dump time vtables match run time order, so when redefine classes reinitializes them, they aren't in the wrong order.
Reviewed-by: dcubed, acorn
1 /*
2 * Copyright (c) 1999, 2011, 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.
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23 */
25 #include "precompiled.hpp"
26 #include "memory/genCollectedHeap.hpp"
27 #include "memory/resourceArea.hpp"
28 #include "memory/threadLocalAllocBuffer.inline.hpp"
29 #include "memory/universe.inline.hpp"
30 #include "oops/oop.inline.hpp"
31 #include "utilities/copy.hpp"
32 #ifdef TARGET_OS_FAMILY_linux
33 # include "thread_linux.inline.hpp"
34 #endif
35 #ifdef TARGET_OS_FAMILY_solaris
36 # include "thread_solaris.inline.hpp"
37 #endif
38 #ifdef TARGET_OS_FAMILY_windows
39 # include "thread_windows.inline.hpp"
40 #endif
42 // Thread-Local Edens support
44 // static member initialization
45 unsigned ThreadLocalAllocBuffer::_target_refills = 0;
46 GlobalTLABStats* ThreadLocalAllocBuffer::_global_stats = NULL;
48 void ThreadLocalAllocBuffer::clear_before_allocation() {
49 _slow_refill_waste += (unsigned)remaining();
50 make_parsable(true); // also retire the TLAB
51 }
53 void ThreadLocalAllocBuffer::accumulate_statistics_before_gc() {
54 global_stats()->initialize();
56 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
57 thread->tlab().accumulate_statistics();
58 thread->tlab().initialize_statistics();
59 }
61 // Publish new stats if some allocation occurred.
62 if (global_stats()->allocation() != 0) {
63 global_stats()->publish();
64 if (PrintTLAB) {
65 global_stats()->print();
66 }
67 }
68 }
70 void ThreadLocalAllocBuffer::accumulate_statistics() {
71 size_t capacity = Universe::heap()->tlab_capacity(myThread()) / HeapWordSize;
72 size_t unused = Universe::heap()->unsafe_max_tlab_alloc(myThread()) / HeapWordSize;
73 size_t used = capacity - unused;
75 // Update allocation history if a reasonable amount of eden was allocated.
76 bool update_allocation_history = used > 0.5 * capacity;
78 _gc_waste += (unsigned)remaining();
80 if (PrintTLAB && (_number_of_refills > 0 || Verbose)) {
81 print_stats("gc");
82 }
84 if (_number_of_refills > 0) {
86 if (update_allocation_history) {
87 // Average the fraction of eden allocated in a tlab by this
88 // thread for use in the next resize operation.
89 // _gc_waste is not subtracted because it's included in
90 // "used".
91 size_t allocation = _number_of_refills * desired_size();
92 double alloc_frac = allocation / (double) used;
93 _allocation_fraction.sample(alloc_frac);
94 }
95 global_stats()->update_allocating_threads();
96 global_stats()->update_number_of_refills(_number_of_refills);
97 global_stats()->update_allocation(_number_of_refills * desired_size());
98 global_stats()->update_gc_waste(_gc_waste);
99 global_stats()->update_slow_refill_waste(_slow_refill_waste);
100 global_stats()->update_fast_refill_waste(_fast_refill_waste);
102 } else {
103 assert(_number_of_refills == 0 && _fast_refill_waste == 0 &&
104 _slow_refill_waste == 0 && _gc_waste == 0,
105 "tlab stats == 0");
106 }
107 global_stats()->update_slow_allocations(_slow_allocations);
108 }
110 // Fills the current tlab with a dummy filler array to create
111 // an illusion of a contiguous Eden and optionally retires the tlab.
112 // Waste accounting should be done in caller as appropriate; see,
113 // for example, clear_before_allocation().
114 void ThreadLocalAllocBuffer::make_parsable(bool retire) {
115 if (end() != NULL) {
116 invariants();
118 if (retire) {
119 myThread()->incr_allocated_bytes(used_bytes());
120 }
122 CollectedHeap::fill_with_object(top(), hard_end(), retire);
124 if (retire || ZeroTLAB) { // "Reset" the TLAB
125 set_start(NULL);
126 set_top(NULL);
127 set_pf_top(NULL);
128 set_end(NULL);
129 }
130 }
131 assert(!(retire || ZeroTLAB) ||
132 (start() == NULL && end() == NULL && top() == NULL),
133 "TLAB must be reset");
134 }
136 void ThreadLocalAllocBuffer::resize_all_tlabs() {
137 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
138 thread->tlab().resize();
139 }
140 }
142 void ThreadLocalAllocBuffer::resize() {
144 if (ResizeTLAB) {
145 // Compute the next tlab size using expected allocation amount
146 size_t alloc = (size_t)(_allocation_fraction.average() *
147 (Universe::heap()->tlab_capacity(myThread()) / HeapWordSize));
148 size_t new_size = alloc / _target_refills;
150 new_size = MIN2(MAX2(new_size, min_size()), max_size());
152 size_t aligned_new_size = align_object_size(new_size);
154 if (PrintTLAB && Verbose) {
155 gclog_or_tty->print("TLAB new size: thread: " INTPTR_FORMAT " [id: %2d]"
156 " refills %d alloc: %8.6f desired_size: " SIZE_FORMAT " -> " SIZE_FORMAT "\n",
157 myThread(), myThread()->osthread()->thread_id(),
158 _target_refills, _allocation_fraction.average(), desired_size(), aligned_new_size);
159 }
160 set_desired_size(aligned_new_size);
162 set_refill_waste_limit(initial_refill_waste_limit());
163 }
164 }
166 void ThreadLocalAllocBuffer::initialize_statistics() {
167 _number_of_refills = 0;
168 _fast_refill_waste = 0;
169 _slow_refill_waste = 0;
170 _gc_waste = 0;
171 _slow_allocations = 0;
172 }
174 void ThreadLocalAllocBuffer::fill(HeapWord* start,
175 HeapWord* top,
176 size_t new_size) {
177 _number_of_refills++;
178 if (PrintTLAB && Verbose) {
179 print_stats("fill");
180 }
181 assert(top <= start + new_size - alignment_reserve(), "size too small");
182 initialize(start, top, start + new_size - alignment_reserve());
184 // Reset amount of internal fragmentation
185 set_refill_waste_limit(initial_refill_waste_limit());
186 }
188 void ThreadLocalAllocBuffer::initialize(HeapWord* start,
189 HeapWord* top,
190 HeapWord* end) {
191 set_start(start);
192 set_top(top);
193 set_pf_top(top);
194 set_end(end);
195 invariants();
196 }
198 void ThreadLocalAllocBuffer::initialize() {
199 initialize(NULL, // start
200 NULL, // top
201 NULL); // end
203 set_desired_size(initial_desired_size());
205 // Following check is needed because at startup the main (primordial)
206 // thread is initialized before the heap is. The initialization for
207 // this thread is redone in startup_initialization below.
208 if (Universe::heap() != NULL) {
209 size_t capacity = Universe::heap()->tlab_capacity(myThread()) / HeapWordSize;
210 double alloc_frac = desired_size() * target_refills() / (double) capacity;
211 _allocation_fraction.sample(alloc_frac);
212 }
214 set_refill_waste_limit(initial_refill_waste_limit());
216 initialize_statistics();
217 }
219 void ThreadLocalAllocBuffer::startup_initialization() {
221 // Assuming each thread's active tlab is, on average,
222 // 1/2 full at a GC
223 _target_refills = 100 / (2 * TLABWasteTargetPercent);
224 _target_refills = MAX2(_target_refills, (unsigned)1U);
226 _global_stats = new GlobalTLABStats();
228 // During jvm startup, the main (primordial) thread is initialized
229 // before the heap is initialized. So reinitialize it now.
230 guarantee(Thread::current()->is_Java_thread(), "tlab initialization thread not Java thread");
231 Thread::current()->tlab().initialize();
233 if (PrintTLAB && Verbose) {
234 gclog_or_tty->print("TLAB min: " SIZE_FORMAT " initial: " SIZE_FORMAT " max: " SIZE_FORMAT "\n",
235 min_size(), Thread::current()->tlab().initial_desired_size(), max_size());
236 }
237 }
239 size_t ThreadLocalAllocBuffer::initial_desired_size() {
240 size_t init_sz;
242 if (TLABSize > 0) {
243 init_sz = MIN2(TLABSize / HeapWordSize, max_size());
244 } else if (global_stats() == NULL) {
245 // Startup issue - main thread initialized before heap initialized.
246 init_sz = min_size();
247 } else {
248 // Initial size is a function of the average number of allocating threads.
249 unsigned nof_threads = global_stats()->allocating_threads_avg();
251 init_sz = (Universe::heap()->tlab_capacity(myThread()) / HeapWordSize) /
252 (nof_threads * target_refills());
253 init_sz = align_object_size(init_sz);
254 init_sz = MIN2(MAX2(init_sz, min_size()), max_size());
255 }
256 return init_sz;
257 }
259 const size_t ThreadLocalAllocBuffer::max_size() {
261 // TLABs can't be bigger than we can fill with a int[Integer.MAX_VALUE].
262 // This restriction could be removed by enabling filling with multiple arrays.
263 // If we compute that the reasonable way as
264 // header_size + ((sizeof(jint) * max_jint) / HeapWordSize)
265 // we'll overflow on the multiply, so we do the divide first.
266 // We actually lose a little by dividing first,
267 // but that just makes the TLAB somewhat smaller than the biggest array,
268 // which is fine, since we'll be able to fill that.
270 size_t unaligned_max_size = typeArrayOopDesc::header_size(T_INT) +
271 sizeof(jint) *
272 ((juint) max_jint / (size_t) HeapWordSize);
273 return align_size_down(unaligned_max_size, MinObjAlignment);
274 }
276 void ThreadLocalAllocBuffer::print_stats(const char* tag) {
277 Thread* thrd = myThread();
278 size_t waste = _gc_waste + _slow_refill_waste + _fast_refill_waste;
279 size_t alloc = _number_of_refills * _desired_size;
280 double waste_percent = alloc == 0 ? 0.0 :
281 100.0 * waste / alloc;
282 size_t tlab_used = Universe::heap()->tlab_capacity(thrd) -
283 Universe::heap()->unsafe_max_tlab_alloc(thrd);
284 gclog_or_tty->print("TLAB: %s thread: " INTPTR_FORMAT " [id: %2d]"
285 " desired_size: " SIZE_FORMAT "KB"
286 " slow allocs: %d refill waste: " SIZE_FORMAT "B"
287 " alloc:%8.5f %8.0fKB refills: %d waste %4.1f%% gc: %dB"
288 " slow: %dB fast: %dB\n",
289 tag, thrd, thrd->osthread()->thread_id(),
290 _desired_size / (K / HeapWordSize),
291 _slow_allocations, _refill_waste_limit * HeapWordSize,
292 _allocation_fraction.average(),
293 _allocation_fraction.average() * tlab_used / K,
294 _number_of_refills, waste_percent,
295 _gc_waste * HeapWordSize,
296 _slow_refill_waste * HeapWordSize,
297 _fast_refill_waste * HeapWordSize);
298 }
300 void ThreadLocalAllocBuffer::verify() {
301 HeapWord* p = start();
302 HeapWord* t = top();
303 HeapWord* prev_p = NULL;
304 while (p < t) {
305 oop(p)->verify();
306 prev_p = p;
307 p += oop(p)->size();
308 }
309 guarantee(p == top(), "end of last object must match end of space");
310 }
312 Thread* ThreadLocalAllocBuffer::myThread() {
313 return (Thread*)(((char *)this) +
314 in_bytes(start_offset()) -
315 in_bytes(Thread::tlab_start_offset()));
316 }
319 GlobalTLABStats::GlobalTLABStats() :
320 _allocating_threads_avg(TLABAllocationWeight) {
322 initialize();
324 _allocating_threads_avg.sample(1); // One allocating thread at startup
326 if (UsePerfData) {
328 EXCEPTION_MARK;
329 ResourceMark rm;
331 char* cname = PerfDataManager::counter_name("tlab", "allocThreads");
332 _perf_allocating_threads =
333 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_None, CHECK);
335 cname = PerfDataManager::counter_name("tlab", "fills");
336 _perf_total_refills =
337 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_None, CHECK);
339 cname = PerfDataManager::counter_name("tlab", "maxFills");
340 _perf_max_refills =
341 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_None, CHECK);
343 cname = PerfDataManager::counter_name("tlab", "alloc");
344 _perf_allocation =
345 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK);
347 cname = PerfDataManager::counter_name("tlab", "gcWaste");
348 _perf_gc_waste =
349 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK);
351 cname = PerfDataManager::counter_name("tlab", "maxGcWaste");
352 _perf_max_gc_waste =
353 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK);
355 cname = PerfDataManager::counter_name("tlab", "slowWaste");
356 _perf_slow_refill_waste =
357 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK);
359 cname = PerfDataManager::counter_name("tlab", "maxSlowWaste");
360 _perf_max_slow_refill_waste =
361 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK);
363 cname = PerfDataManager::counter_name("tlab", "fastWaste");
364 _perf_fast_refill_waste =
365 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK);
367 cname = PerfDataManager::counter_name("tlab", "maxFastWaste");
368 _perf_max_fast_refill_waste =
369 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK);
371 cname = PerfDataManager::counter_name("tlab", "slowAlloc");
372 _perf_slow_allocations =
373 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_None, CHECK);
375 cname = PerfDataManager::counter_name("tlab", "maxSlowAlloc");
376 _perf_max_slow_allocations =
377 PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_None, CHECK);
378 }
379 }
381 void GlobalTLABStats::initialize() {
382 // Clear counters summarizing info from all threads
383 _allocating_threads = 0;
384 _total_refills = 0;
385 _max_refills = 0;
386 _total_allocation = 0;
387 _total_gc_waste = 0;
388 _max_gc_waste = 0;
389 _total_slow_refill_waste = 0;
390 _max_slow_refill_waste = 0;
391 _total_fast_refill_waste = 0;
392 _max_fast_refill_waste = 0;
393 _total_slow_allocations = 0;
394 _max_slow_allocations = 0;
395 }
397 void GlobalTLABStats::publish() {
398 _allocating_threads_avg.sample(_allocating_threads);
399 if (UsePerfData) {
400 _perf_allocating_threads ->set_value(_allocating_threads);
401 _perf_total_refills ->set_value(_total_refills);
402 _perf_max_refills ->set_value(_max_refills);
403 _perf_allocation ->set_value(_total_allocation);
404 _perf_gc_waste ->set_value(_total_gc_waste);
405 _perf_max_gc_waste ->set_value(_max_gc_waste);
406 _perf_slow_refill_waste ->set_value(_total_slow_refill_waste);
407 _perf_max_slow_refill_waste->set_value(_max_slow_refill_waste);
408 _perf_fast_refill_waste ->set_value(_total_fast_refill_waste);
409 _perf_max_fast_refill_waste->set_value(_max_fast_refill_waste);
410 _perf_slow_allocations ->set_value(_total_slow_allocations);
411 _perf_max_slow_allocations ->set_value(_max_slow_allocations);
412 }
413 }
415 void GlobalTLABStats::print() {
416 size_t waste = _total_gc_waste + _total_slow_refill_waste + _total_fast_refill_waste;
417 double waste_percent = _total_allocation == 0 ? 0.0 :
418 100.0 * waste / _total_allocation;
419 gclog_or_tty->print("TLAB totals: thrds: %d refills: %d max: %d"
420 " slow allocs: %d max %d waste: %4.1f%%"
421 " gc: " SIZE_FORMAT "B max: " SIZE_FORMAT "B"
422 " slow: " SIZE_FORMAT "B max: " SIZE_FORMAT "B"
423 " fast: " SIZE_FORMAT "B max: " SIZE_FORMAT "B\n",
424 _allocating_threads,
425 _total_refills, _max_refills,
426 _total_slow_allocations, _max_slow_allocations,
427 waste_percent,
428 _total_gc_waste * HeapWordSize,
429 _max_gc_waste * HeapWordSize,
430 _total_slow_refill_waste * HeapWordSize,
431 _max_slow_refill_waste * HeapWordSize,
432 _total_fast_refill_waste * HeapWordSize,
433 _max_fast_refill_waste * HeapWordSize);
434 }