1 /*
2 * Copyright (c) 2010, 2017, 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 #include "precompiled.hpp"
26 #include "code/codeCache.hpp"
27 #include "runtime/advancedThresholdPolicy.hpp"
28 #include "runtime/handles.inline.hpp"
29 #include "runtime/simpleThresholdPolicy.inline.hpp"
30 #if INCLUDE_JVMCI
31 #include "jvmci/jvmciRuntime.hpp"
32 #endif
33
34 #ifdef TIERED
35 // Print an event.
36 void AdvancedThresholdPolicy::print_specific(EventType type, const methodHandle& mh, const methodHandle& imh,
37 int bci, CompLevel level) {
38 tty->print(" rate=");
39 if (mh->prev_time() == 0) tty->print("n/a");
40 else tty->print("%f", mh->rate());
41
42 tty->print(" k=%.2lf,%.2lf", threshold_scale(CompLevel_full_profile, Tier3LoadFeedback),
43 threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback));
44
45 }
46
47 void AdvancedThresholdPolicy::initialize() {
48 int count = CICompilerCount;
49 #ifdef _LP64
50 // Turn on ergonomic compiler count selection
51 if (FLAG_IS_DEFAULT(CICompilerCountPerCPU) && FLAG_IS_DEFAULT(CICompilerCount)) {
52 FLAG_SET_DEFAULT(CICompilerCountPerCPU, true);
53 }
54 if (CICompilerCountPerCPU) {
55 // Simple log n seems to grow too slowly for tiered, try something faster: log n * log log n
56 int log_cpu = log2_intptr(os::active_processor_count());
57 int loglog_cpu = log2_intptr(MAX2(log_cpu, 1));
58 count = MAX2(log_cpu * loglog_cpu * 3 / 2, 2);
59 FLAG_SET_ERGO(intx, CICompilerCount, count);
60 }
61 #else
62 // On 32-bit systems, the number of compiler threads is limited to 3.
63 // On these systems, the virtual address space available to the JVM
64 // is usually limited to 2-4 GB (the exact value depends on the platform).
65 // As the compilers (especially C2) can consume a large amount of
66 // memory, scaling the number of compiler threads with the number of
67 // available cores can result in the exhaustion of the address space
68 /// available to the VM and thus cause the VM to crash.
69 if (FLAG_IS_DEFAULT(CICompilerCount)) {
70 count = 3;
71 FLAG_SET_ERGO(intx, CICompilerCount, count);
72 }
73 #endif
74
75 if (TieredStopAtLevel < CompLevel_full_optimization) {
76 // No C2 compiler thread required
77 set_c1_count(count);
78 } else {
79 set_c1_count(MAX2(count / 3, 1));
80 set_c2_count(MAX2(count - c1_count(), 1));
81 }
82 assert(count == c1_count() + c2_count(), "inconsistent compiler thread count");
83
84 // Some inlining tuning
85 #ifdef X86
86 if (FLAG_IS_DEFAULT(InlineSmallCode)) {
87 FLAG_SET_DEFAULT(InlineSmallCode, 2000);
88 }
89 #endif
90
91 #if defined SPARC || defined AARCH64
92 if (FLAG_IS_DEFAULT(InlineSmallCode)) {
93 FLAG_SET_DEFAULT(InlineSmallCode, 2500);
94 }
95 #endif
96
97 set_increase_threshold_at_ratio();
98 set_start_time(os::javaTimeMillis());
99 }
100
101 // update_rate() is called from select_task() while holding a compile queue lock.
102 void AdvancedThresholdPolicy::update_rate(jlong t, Method* m) {
103 // Skip update if counters are absent.
104 // Can't allocate them since we are holding compile queue lock.
105 if (m->method_counters() == NULL) return;
106
107 if (is_old(m)) {
108 // We don't remove old methods from the queue,
109 // so we can just zero the rate.
110 m->set_rate(0);
111 return;
112 }
113
114 // We don't update the rate if we've just came out of a safepoint.
115 // delta_s is the time since last safepoint in milliseconds.
116 jlong delta_s = t - SafepointSynchronize::end_of_last_safepoint();
117 jlong delta_t = t - (m->prev_time() != 0 ? m->prev_time() : start_time()); // milliseconds since the last measurement
118 // How many events were there since the last time?
119 int event_count = m->invocation_count() + m->backedge_count();
120 int delta_e = event_count - m->prev_event_count();
121
122 // We should be running for at least 1ms.
123 if (delta_s >= TieredRateUpdateMinTime) {
124 // And we must've taken the previous point at least 1ms before.
125 if (delta_t >= TieredRateUpdateMinTime && delta_e > 0) {
126 m->set_prev_time(t);
127 m->set_prev_event_count(event_count);
128 m->set_rate((float)delta_e / (float)delta_t); // Rate is events per millisecond
129 } else {
130 if (delta_t > TieredRateUpdateMaxTime && delta_e == 0) {
131 // If nothing happened for 25ms, zero the rate. Don't modify prev values.
132 m->set_rate(0);
133 }
134 }
135 }
136 }
137
138 // Check if this method has been stale from a given number of milliseconds.
139 // See select_task().
140 bool AdvancedThresholdPolicy::is_stale(jlong t, jlong timeout, Method* m) {
141 jlong delta_s = t - SafepointSynchronize::end_of_last_safepoint();
142 jlong delta_t = t - m->prev_time();
143 if (delta_t > timeout && delta_s > timeout) {
144 int event_count = m->invocation_count() + m->backedge_count();
145 int delta_e = event_count - m->prev_event_count();
146 // Return true if there were no events.
147 return delta_e == 0;
148 }
149 return false;
150 }
151
152 // We don't remove old methods from the compile queue even if they have
153 // very low activity. See select_task().
154 bool AdvancedThresholdPolicy::is_old(Method* method) {
155 return method->invocation_count() > 50000 || method->backedge_count() > 500000;
156 }
157
158 double AdvancedThresholdPolicy::weight(Method* method) {
159 return (double)(method->rate() + 1) *
160 (method->invocation_count() + 1) * (method->backedge_count() + 1);
161 }
162
163 // Apply heuristics and return true if x should be compiled before y
164 bool AdvancedThresholdPolicy::compare_methods(Method* x, Method* y) {
165 if (x->highest_comp_level() > y->highest_comp_level()) {
166 // recompilation after deopt
167 return true;
168 } else
169 if (x->highest_comp_level() == y->highest_comp_level()) {
170 if (weight(x) > weight(y)) {
171 return true;
172 }
173 }
174 return false;
175 }
176
177 // Is method profiled enough?
178 bool AdvancedThresholdPolicy::is_method_profiled(Method* method) {
179 MethodData* mdo = method->method_data();
180 if (mdo != NULL) {
181 int i = mdo->invocation_count_delta();
182 int b = mdo->backedge_count_delta();
183 return call_predicate_helper<CompLevel_full_profile>(i, b, 1, method);
184 }
185 return false;
186 }
187
188 // Called with the queue locked and with at least one element
189 CompileTask* AdvancedThresholdPolicy::select_task(CompileQueue* compile_queue) {
190 CompileTask *max_blocking_task = NULL;
191 CompileTask *max_task = NULL;
192 Method* max_method = NULL;
193 jlong t = os::javaTimeMillis();
194 // Iterate through the queue and find a method with a maximum rate.
195 for (CompileTask* task = compile_queue->first(); task != NULL;) {
196 CompileTask* next_task = task->next();
197 Method* method = task->method();
198 update_rate(t, method);
199 if (max_task == NULL) {
200 max_task = task;
201 max_method = method;
202 } else {
203 // If a method has been stale for some time, remove it from the queue.
204 // Blocking tasks and tasks submitted from whitebox API don't become stale
205 if (task->can_become_stale() && is_stale(t, TieredCompileTaskTimeout, method) && !is_old(method)) {
206 if (PrintTieredEvents) {
207 print_event(REMOVE_FROM_QUEUE, method, method, task->osr_bci(), (CompLevel)task->comp_level());
208 }
209 compile_queue->remove_and_mark_stale(task);
210 method->clear_queued_for_compilation();
211 task = next_task;
212 continue;
213 }
214
215 // Select a method with a higher rate
216 if (compare_methods(method, max_method)) {
217 max_task = task;
218 max_method = method;
219 }
220 }
221
222 if (task->is_blocking()) {
223 if (max_blocking_task == NULL || compare_methods(method, max_blocking_task->method())) {
224 max_blocking_task = task;
225 }
226 }
227
228 task = next_task;
229 }
230
231 if (max_blocking_task != NULL) {
232 // In blocking compilation mode, the CompileBroker will make
233 // compilations submitted by a JVMCI compiler thread non-blocking. These
234 // compilations should be scheduled after all blocking compilations
235 // to service non-compiler related compilations sooner and reduce the
236 // chance of such compilations timing out.
237 max_task = max_blocking_task;
238 max_method = max_task->method();
239 }
240
241 if (max_task->comp_level() == CompLevel_full_profile && TieredStopAtLevel > CompLevel_full_profile
242 && is_method_profiled(max_method)) {
243 max_task->set_comp_level(CompLevel_limited_profile);
244 if (PrintTieredEvents) {
245 print_event(UPDATE_IN_QUEUE, max_method, max_method, max_task->osr_bci(), (CompLevel)max_task->comp_level());
246 }
247 }
248
249 return max_task;
250 }
251
252 double AdvancedThresholdPolicy::threshold_scale(CompLevel level, int feedback_k) {
253 double queue_size = CompileBroker::queue_size(level);
254 int comp_count = compiler_count(level);
255 double k = queue_size / (feedback_k * comp_count) + 1;
256
257 // Increase C1 compile threshold when the code cache is filled more
258 // than specified by IncreaseFirstTierCompileThresholdAt percentage.
259 // The main intention is to keep enough free space for C2 compiled code
260 // to achieve peak performance if the code cache is under stress.
261 if ((TieredStopAtLevel == CompLevel_full_optimization) && (level != CompLevel_full_optimization)) {
262 double current_reverse_free_ratio = CodeCache::reverse_free_ratio(CodeCache::get_code_blob_type(level));
263 if (current_reverse_free_ratio > _increase_threshold_at_ratio) {
264 k *= exp(current_reverse_free_ratio - _increase_threshold_at_ratio);
265 }
266 }
267 return k;
268 }
269
270 // Call and loop predicates determine whether a transition to a higher
271 // compilation level should be performed (pointers to predicate functions
272 // are passed to common()).
273 // Tier?LoadFeedback is basically a coefficient that determines of
274 // how many methods per compiler thread can be in the queue before
275 // the threshold values double.
276 bool AdvancedThresholdPolicy::loop_predicate(int i, int b, CompLevel cur_level, Method* method) {
277 switch(cur_level) {
278 case CompLevel_aot: {
279 double k = threshold_scale(CompLevel_full_profile, Tier3LoadFeedback);
280 return loop_predicate_helper<CompLevel_aot>(i, b, k, method);
281 }
282 case CompLevel_none:
283 case CompLevel_limited_profile: {
284 double k = threshold_scale(CompLevel_full_profile, Tier3LoadFeedback);
285 return loop_predicate_helper<CompLevel_none>(i, b, k, method);
286 }
287 case CompLevel_full_profile: {
288 double k = threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback);
289 return loop_predicate_helper<CompLevel_full_profile>(i, b, k, method);
290 }
291 default:
292 return true;
293 }
294 }
295
296 bool AdvancedThresholdPolicy::call_predicate(int i, int b, CompLevel cur_level, Method* method) {
297 switch(cur_level) {
298 case CompLevel_aot: {
299 double k = threshold_scale(CompLevel_full_profile, Tier3LoadFeedback);
300 return call_predicate_helper<CompLevel_aot>(i, b, k, method);
301 }
302 case CompLevel_none:
303 case CompLevel_limited_profile: {
304 double k = threshold_scale(CompLevel_full_profile, Tier3LoadFeedback);
305 return call_predicate_helper<CompLevel_none>(i, b, k, method);
306 }
307 case CompLevel_full_profile: {
308 double k = threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback);
309 return call_predicate_helper<CompLevel_full_profile>(i, b, k, method);
310 }
311 default:
312 return true;
313 }
314 }
315
316 // If a method is old enough and is still in the interpreter we would want to
317 // start profiling without waiting for the compiled method to arrive.
318 // We also take the load on compilers into the account.
319 bool AdvancedThresholdPolicy::should_create_mdo(Method* method, CompLevel cur_level) {
320 if (cur_level == CompLevel_none &&
321 CompileBroker::queue_size(CompLevel_full_optimization) <=
322 Tier3DelayOn * compiler_count(CompLevel_full_optimization)) {
323 int i = method->invocation_count();
324 int b = method->backedge_count();
325 double k = Tier0ProfilingStartPercentage / 100.0;
326 return call_predicate_helper<CompLevel_none>(i, b, k, method) || loop_predicate_helper<CompLevel_none>(i, b, k, method);
327 }
328 return false;
329 }
330
331 // Inlining control: if we're compiling a profiled method with C1 and the callee
332 // is known to have OSRed in a C2 version, don't inline it.
333 bool AdvancedThresholdPolicy::should_not_inline(ciEnv* env, ciMethod* callee) {
334 CompLevel comp_level = (CompLevel)env->comp_level();
335 if (comp_level == CompLevel_full_profile ||
336 comp_level == CompLevel_limited_profile) {
337 return callee->highest_osr_comp_level() == CompLevel_full_optimization;
338 }
339 return false;
340 }
341
342 // Create MDO if necessary.
343 void AdvancedThresholdPolicy::create_mdo(const methodHandle& mh, JavaThread* THREAD) {
344 if (mh->is_native() ||
345 mh->is_abstract() ||
346 mh->is_accessor() ||
347 mh->is_constant_getter()) {
348 return;
349 }
350 if (mh->method_data() == NULL) {
351 Method::build_interpreter_method_data(mh, CHECK_AND_CLEAR);
352 }
353 }
354
355
356 /*
357 * Method states:
358 * 0 - interpreter (CompLevel_none)
359 * 1 - pure C1 (CompLevel_simple)
360 * 2 - C1 with invocation and backedge counting (CompLevel_limited_profile)
361 * 3 - C1 with full profiling (CompLevel_full_profile)
362 * 4 - C2 (CompLevel_full_optimization)
363 *
364 * Common state transition patterns:
365 * a. 0 -> 3 -> 4.
366 * The most common path. But note that even in this straightforward case
367 * profiling can start at level 0 and finish at level 3.
368 *
369 * b. 0 -> 2 -> 3 -> 4.
370 * This case occurs when the load on C2 is deemed too high. So, instead of transitioning
371 * into state 3 directly and over-profiling while a method is in the C2 queue we transition to
372 * level 2 and wait until the load on C2 decreases. This path is disabled for OSRs.
373 *
374 * c. 0 -> (3->2) -> 4.
375 * In this case we enqueue a method for compilation at level 3, but the C1 queue is long enough
376 * to enable the profiling to fully occur at level 0. In this case we change the compilation level
377 * of the method to 2 while the request is still in-queue, because it'll allow it to run much faster
378 * without full profiling while c2 is compiling.
379 *
380 * d. 0 -> 3 -> 1 or 0 -> 2 -> 1.
381 * After a method was once compiled with C1 it can be identified as trivial and be compiled to
382 * level 1. These transition can also occur if a method can't be compiled with C2 but can with C1.
383 *
384 * e. 0 -> 4.
385 * This can happen if a method fails C1 compilation (it will still be profiled in the interpreter)
386 * or because of a deopt that didn't require reprofiling (compilation won't happen in this case because
387 * the compiled version already exists).
388 *
389 * Note that since state 0 can be reached from any other state via deoptimization different loops
390 * are possible.
391 *
392 */
393
394 // Common transition function. Given a predicate determines if a method should transition to another level.
395 CompLevel AdvancedThresholdPolicy::common(Predicate p, Method* method, CompLevel cur_level, bool disable_feedback) {
396 CompLevel next_level = cur_level;
397 int i = method->invocation_count();
398 int b = method->backedge_count();
399
400 if (is_trivial(method)) {
401 next_level = CompLevel_simple;
402 } else {
403 switch(cur_level) {
404 default: break;
405 case CompLevel_aot: {
406 // If we were at full profile level, would we switch to full opt?
407 if (common(p, method, CompLevel_full_profile, disable_feedback) == CompLevel_full_optimization) {
408 next_level = CompLevel_full_optimization;
409 } else if (disable_feedback || (CompileBroker::queue_size(CompLevel_full_optimization) <=
410 Tier3DelayOff * compiler_count(CompLevel_full_optimization) &&
411 (this->*p)(i, b, cur_level, method))) {
412 next_level = CompLevel_full_profile;
413 }
414 }
415 break;
416 case CompLevel_none:
417 // If we were at full profile level, would we switch to full opt?
418 if (common(p, method, CompLevel_full_profile, disable_feedback) == CompLevel_full_optimization) {
419 next_level = CompLevel_full_optimization;
420 } else if ((this->*p)(i, b, cur_level, method)) {
421 #if INCLUDE_JVMCI
422 if (EnableJVMCI && UseJVMCICompiler) {
423 // Since JVMCI takes a while to warm up, its queue inevitably backs up during
424 // early VM execution. As of 2014-06-13, JVMCI's inliner assumes that the root
425 // compilation method and all potential inlinees have mature profiles (which
426 // includes type profiling). If it sees immature profiles, JVMCI's inliner
427 // can perform pathologically bad (e.g., causing OutOfMemoryErrors due to
428 // exploring/inlining too many graphs). Since a rewrite of the inliner is
429 // in progress, we simply disable the dialing back heuristic for now and will
430 // revisit this decision once the new inliner is completed.
431 next_level = CompLevel_full_profile;
432 } else
433 #endif
434 {
435 // C1-generated fully profiled code is about 30% slower than the limited profile
436 // code that has only invocation and backedge counters. The observation is that
437 // if C2 queue is large enough we can spend too much time in the fully profiled code
438 // while waiting for C2 to pick the method from the queue. To alleviate this problem
439 // we introduce a feedback on the C2 queue size. If the C2 queue is sufficiently long
440 // we choose to compile a limited profiled version and then recompile with full profiling
441 // when the load on C2 goes down.
442 if (!disable_feedback && CompileBroker::queue_size(CompLevel_full_optimization) >
443 Tier3DelayOn * compiler_count(CompLevel_full_optimization)) {
444 next_level = CompLevel_limited_profile;
445 } else {
446 next_level = CompLevel_full_profile;
447 }
448 }
449 }
450 break;
451 case CompLevel_limited_profile:
452 if (is_method_profiled(method)) {
453 // Special case: we got here because this method was fully profiled in the interpreter.
454 next_level = CompLevel_full_optimization;
455 } else {
456 MethodData* mdo = method->method_data();
457 if (mdo != NULL) {
458 if (mdo->would_profile()) {
459 if (disable_feedback || (CompileBroker::queue_size(CompLevel_full_optimization) <=
460 Tier3DelayOff * compiler_count(CompLevel_full_optimization) &&
461 (this->*p)(i, b, cur_level, method))) {
462 next_level = CompLevel_full_profile;
463 }
464 } else {
465 next_level = CompLevel_full_optimization;
466 }
467 } else {
468 // If there is no MDO we need to profile
469 if (disable_feedback || (CompileBroker::queue_size(CompLevel_full_optimization) <=
470 Tier3DelayOff * compiler_count(CompLevel_full_optimization) &&
471 (this->*p)(i, b, cur_level, method))) {
472 next_level = CompLevel_full_profile;
473 }
474 }
475 }
476 break;
477 case CompLevel_full_profile:
478 {
479 MethodData* mdo = method->method_data();
480 if (mdo != NULL) {
481 if (mdo->would_profile()) {
482 int mdo_i = mdo->invocation_count_delta();
483 int mdo_b = mdo->backedge_count_delta();
484 if ((this->*p)(mdo_i, mdo_b, cur_level, method)) {
485 next_level = CompLevel_full_optimization;
486 }
487 } else {
488 next_level = CompLevel_full_optimization;
489 }
490 }
491 }
492 break;
493 }
494 }
495 return MIN2(next_level, (CompLevel)TieredStopAtLevel);
496 }
497
498 // Determine if a method should be compiled with a normal entry point at a different level.
499 CompLevel AdvancedThresholdPolicy::call_event(Method* method, CompLevel cur_level, JavaThread * thread) {
500 CompLevel osr_level = MIN2((CompLevel) method->highest_osr_comp_level(),
501 common(&AdvancedThresholdPolicy::loop_predicate, method, cur_level, true));
502 CompLevel next_level = common(&AdvancedThresholdPolicy::call_predicate, method, cur_level);
503
504 // If OSR method level is greater than the regular method level, the levels should be
505 // equalized by raising the regular method level in order to avoid OSRs during each
506 // invocation of the method.
507 if (osr_level == CompLevel_full_optimization && cur_level == CompLevel_full_profile) {
508 MethodData* mdo = method->method_data();
509 guarantee(mdo != NULL, "MDO should not be NULL");
510 if (mdo->invocation_count() >= 1) {
511 next_level = CompLevel_full_optimization;
512 }
513 } else {
514 next_level = MAX2(osr_level, next_level);
515 }
516 #if INCLUDE_JVMCI
517 if (UseJVMCICompiler) {
518 next_level = JVMCIRuntime::adjust_comp_level(method, false, next_level, thread);
519 }
520 #endif
521 return next_level;
522 }
523
524 // Determine if we should do an OSR compilation of a given method.
525 CompLevel AdvancedThresholdPolicy::loop_event(Method* method, CompLevel cur_level, JavaThread * thread) {
526 CompLevel next_level = common(&AdvancedThresholdPolicy::loop_predicate, method, cur_level, true);
527 if (cur_level == CompLevel_none) {
528 // If there is a live OSR method that means that we deopted to the interpreter
529 // for the transition.
530 CompLevel osr_level = MIN2((CompLevel)method->highest_osr_comp_level(), next_level);
531 if (osr_level > CompLevel_none) {
532 return osr_level;
533 }
534 }
535 #if INCLUDE_JVMCI
536 if (UseJVMCICompiler) {
537 next_level = JVMCIRuntime::adjust_comp_level(method, true, next_level, thread);
538 }
539 #endif
540 return next_level;
541 }
542
543 // Update the rate and submit compile
544 void AdvancedThresholdPolicy::submit_compile(const methodHandle& mh, int bci, CompLevel level, JavaThread* thread) {
545 int hot_count = (bci == InvocationEntryBci) ? mh->invocation_count() : mh->backedge_count();
546 update_rate(os::javaTimeMillis(), mh());
547 CompileBroker::compile_method(mh, bci, level, mh, hot_count, CompileTask::Reason_Tiered, thread);
548 }
549
550 bool AdvancedThresholdPolicy::maybe_switch_to_aot(const methodHandle& mh, CompLevel cur_level, CompLevel next_level, JavaThread* thread) {
551 if (UseAOT && !delay_compilation_during_startup()) {
552 if (cur_level == CompLevel_full_profile || cur_level == CompLevel_none) {
553 // If the current level is full profile or interpreter and we're switching to any other level,
554 // activate the AOT code back first so that we won't waste time overprofiling.
555 compile(mh, InvocationEntryBci, CompLevel_aot, thread);
556 // Fall through for JIT compilation.
557 }
558 if (next_level == CompLevel_limited_profile && cur_level != CompLevel_aot && mh->has_aot_code()) {
559 // If the next level is limited profile, use the aot code (if there is any),
560 // since it's essentially the same thing.
561 compile(mh, InvocationEntryBci, CompLevel_aot, thread);
562 // Not need to JIT, we're done.
563 return true;
564 }
565 }
566 return false;
567 }
568
569
570 // Handle the invocation event.
571 void AdvancedThresholdPolicy::method_invocation_event(const methodHandle& mh, const methodHandle& imh,
572 CompLevel level, CompiledMethod* nm, JavaThread* thread) {
573 if (should_create_mdo(mh(), level)) {
574 create_mdo(mh, thread);
575 }
576 CompLevel next_level = call_event(mh(), level, thread);
577 if (next_level != level) {
578 if (maybe_switch_to_aot(mh, level, next_level, thread)) {
579 // No JITting necessary
580 return;
581 }
582 if (is_compilation_enabled() && !CompileBroker::compilation_is_in_queue(mh)) {
583 compile(mh, InvocationEntryBci, next_level, thread);
584 }
585 }
586 }
587
588 // Handle the back branch event. Notice that we can compile the method
589 // with a regular entry from here.
590 void AdvancedThresholdPolicy::method_back_branch_event(const methodHandle& mh, const methodHandle& imh,
591 int bci, CompLevel level, CompiledMethod* nm, JavaThread* thread) {
592 if (should_create_mdo(mh(), level)) {
593 create_mdo(mh, thread);
594 }
595 // Check if MDO should be created for the inlined method
596 if (should_create_mdo(imh(), level)) {
597 create_mdo(imh, thread);
598 }
599
600 if (is_compilation_enabled()) {
601 CompLevel next_osr_level = loop_event(imh(), level, thread);
602 CompLevel max_osr_level = (CompLevel)imh->highest_osr_comp_level();
603 // At the very least compile the OSR version
604 if (!CompileBroker::compilation_is_in_queue(imh) && (next_osr_level != level)) {
605 compile(imh, bci, next_osr_level, thread);
606 }
607
608 // Use loop event as an opportunity to also check if there's been
609 // enough calls.
610 CompLevel cur_level, next_level;
611 if (mh() != imh()) { // If there is an enclosing method
612 if (level == CompLevel_aot) {
613 // Recompile the enclosing method to prevent infinite OSRs. Stay at AOT level while it's compiling.
614 if (max_osr_level != CompLevel_none && !CompileBroker::compilation_is_in_queue(mh)) {
615 compile(mh, InvocationEntryBci, MIN2((CompLevel)TieredStopAtLevel, CompLevel_full_profile), thread);
616 }
617 } else {
618 // Current loop event level is not AOT
619 guarantee(nm != NULL, "Should have nmethod here");
620 cur_level = comp_level(mh());
621 next_level = call_event(mh(), cur_level, thread);
622
623 if (max_osr_level == CompLevel_full_optimization) {
624 // The inlinee OSRed to full opt, we need to modify the enclosing method to avoid deopts
625 bool make_not_entrant = false;
626 if (nm->is_osr_method()) {
627 // This is an osr method, just make it not entrant and recompile later if needed
628 make_not_entrant = true;
629 } else {
630 if (next_level != CompLevel_full_optimization) {
631 // next_level is not full opt, so we need to recompile the
632 // enclosing method without the inlinee
633 cur_level = CompLevel_none;
634 make_not_entrant = true;
635 }
636 }
637 if (make_not_entrant) {
638 if (PrintTieredEvents) {
639 int osr_bci = nm->is_osr_method() ? nm->osr_entry_bci() : InvocationEntryBci;
640 print_event(MAKE_NOT_ENTRANT, mh(), mh(), osr_bci, level);
641 }
642 nm->make_not_entrant();
643 }
644 }
645 // Fix up next_level if necessary to avoid deopts
646 if (next_level == CompLevel_limited_profile && max_osr_level == CompLevel_full_profile) {
647 next_level = CompLevel_full_profile;
648 }
649 if (cur_level != next_level) {
650 if (!maybe_switch_to_aot(mh, cur_level, next_level, thread) && !CompileBroker::compilation_is_in_queue(mh)) {
651 compile(mh, InvocationEntryBci, next_level, thread);
652 }
653 }
654 }
655 } else {
656 cur_level = comp_level(mh());
657 next_level = call_event(mh(), cur_level, thread);
658 if (next_level != cur_level) {
659 if (!maybe_switch_to_aot(mh, cur_level, next_level, thread) && !CompileBroker::compilation_is_in_queue(mh)) {
660 compile(mh, InvocationEntryBci, next_level, thread);
661 }
662 }
663 }
664 }
665 }
666
667 #endif // TIERED