| /* |
| * Copyright (c) 2010, 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. |
| * |
| * 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. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "compiler/compileBroker.hpp" |
| #include "compiler/compilerOracle.hpp" |
| #include "memory/resourceArea.hpp" |
| #include "runtime/arguments.hpp" |
| #include "runtime/handles.inline.hpp" |
| #include "runtime/safepointVerifiers.hpp" |
| #include "runtime/tieredThresholdPolicy.hpp" |
| #include "code/scopeDesc.hpp" |
| #include "oops/method.inline.hpp" |
| #if INCLUDE_JVMCI |
| #include "jvmci/jvmciRuntime.hpp" |
| #endif |
| |
| #ifdef TIERED |
| |
| #include "c1/c1_Compiler.hpp" |
| #include "opto/c2compiler.hpp" |
| |
| template<CompLevel level> |
| bool TieredThresholdPolicy::call_predicate_helper(int i, int b, double scale, Method* method) { |
| double threshold_scaling; |
| if (CompilerOracle::has_option_value(method, "CompileThresholdScaling", threshold_scaling)) { |
| scale *= threshold_scaling; |
| } |
| switch(level) { |
| case CompLevel_aot: |
| return (i >= Tier3AOTInvocationThreshold * scale) || |
| (i >= Tier3AOTMinInvocationThreshold * scale && i + b >= Tier3AOTCompileThreshold * scale); |
| case CompLevel_none: |
| case CompLevel_limited_profile: |
| return (i >= Tier3InvocationThreshold * scale) || |
| (i >= Tier3MinInvocationThreshold * scale && i + b >= Tier3CompileThreshold * scale); |
| case CompLevel_full_profile: |
| return (i >= Tier4InvocationThreshold * scale) || |
| (i >= Tier4MinInvocationThreshold * scale && i + b >= Tier4CompileThreshold * scale); |
| } |
| return true; |
| } |
| |
| template<CompLevel level> |
| bool TieredThresholdPolicy::loop_predicate_helper(int i, int b, double scale, Method* method) { |
| double threshold_scaling; |
| if (CompilerOracle::has_option_value(method, "CompileThresholdScaling", threshold_scaling)) { |
| scale *= threshold_scaling; |
| } |
| switch(level) { |
| case CompLevel_aot: |
| return b >= Tier3AOTBackEdgeThreshold * scale; |
| case CompLevel_none: |
| case CompLevel_limited_profile: |
| return b >= Tier3BackEdgeThreshold * scale; |
| case CompLevel_full_profile: |
| return b >= Tier4BackEdgeThreshold * scale; |
| } |
| return true; |
| } |
| |
| // Simple methods are as good being compiled with C1 as C2. |
| // Determine if a given method is such a case. |
| bool TieredThresholdPolicy::is_trivial(Method* method) { |
| if (method->is_accessor() || |
| method->is_constant_getter()) { |
| return true; |
| } |
| return false; |
| } |
| |
| inline CompLevel TieredThresholdPolicy::comp_level(Method* method) { |
| CompiledMethod *nm = method->code(); |
| if (nm != NULL && nm->is_in_use()) { |
| return (CompLevel)nm->comp_level(); |
| } |
| return CompLevel_none; |
| } |
| |
| void TieredThresholdPolicy::print_counters(const char* prefix, const methodHandle& mh) { |
| int invocation_count = mh->invocation_count(); |
| int backedge_count = mh->backedge_count(); |
| MethodData* mdh = mh->method_data(); |
| int mdo_invocations = 0, mdo_backedges = 0; |
| int mdo_invocations_start = 0, mdo_backedges_start = 0; |
| if (mdh != NULL) { |
| mdo_invocations = mdh->invocation_count(); |
| mdo_backedges = mdh->backedge_count(); |
| mdo_invocations_start = mdh->invocation_count_start(); |
| mdo_backedges_start = mdh->backedge_count_start(); |
| } |
| tty->print(" %stotal=%d,%d %smdo=%d(%d),%d(%d)", prefix, |
| invocation_count, backedge_count, prefix, |
| mdo_invocations, mdo_invocations_start, |
| mdo_backedges, mdo_backedges_start); |
| tty->print(" %smax levels=%d,%d", prefix, |
| mh->highest_comp_level(), mh->highest_osr_comp_level()); |
| } |
| |
| // Print an event. |
| void TieredThresholdPolicy::print_event(EventType type, const methodHandle& mh, const methodHandle& imh, |
| int bci, CompLevel level) { |
| bool inlinee_event = mh() != imh(); |
| |
| ttyLocker tty_lock; |
| tty->print("%lf: [", os::elapsedTime()); |
| |
| switch(type) { |
| case CALL: |
| tty->print("call"); |
| break; |
| case LOOP: |
| tty->print("loop"); |
| break; |
| case COMPILE: |
| tty->print("compile"); |
| break; |
| case REMOVE_FROM_QUEUE: |
| tty->print("remove-from-queue"); |
| break; |
| case UPDATE_IN_QUEUE: |
| tty->print("update-in-queue"); |
| break; |
| case REPROFILE: |
| tty->print("reprofile"); |
| break; |
| case MAKE_NOT_ENTRANT: |
| tty->print("make-not-entrant"); |
| break; |
| default: |
| tty->print("unknown"); |
| } |
| |
| tty->print(" level=%d ", level); |
| |
| ResourceMark rm; |
| char *method_name = mh->name_and_sig_as_C_string(); |
| tty->print("[%s", method_name); |
| if (inlinee_event) { |
| char *inlinee_name = imh->name_and_sig_as_C_string(); |
| tty->print(" [%s]] ", inlinee_name); |
| } |
| else tty->print("] "); |
| tty->print("@%d queues=%d,%d", bci, CompileBroker::queue_size(CompLevel_full_profile), |
| CompileBroker::queue_size(CompLevel_full_optimization)); |
| |
| print_specific(type, mh, imh, bci, level); |
| |
| if (type != COMPILE) { |
| print_counters("", mh); |
| if (inlinee_event) { |
| print_counters("inlinee ", imh); |
| } |
| tty->print(" compilable="); |
| bool need_comma = false; |
| if (!mh->is_not_compilable(CompLevel_full_profile)) { |
| tty->print("c1"); |
| need_comma = true; |
| } |
| if (!mh->is_not_osr_compilable(CompLevel_full_profile)) { |
| if (need_comma) tty->print(","); |
| tty->print("c1-osr"); |
| need_comma = true; |
| } |
| if (!mh->is_not_compilable(CompLevel_full_optimization)) { |
| if (need_comma) tty->print(","); |
| tty->print("c2"); |
| need_comma = true; |
| } |
| if (!mh->is_not_osr_compilable(CompLevel_full_optimization)) { |
| if (need_comma) tty->print(","); |
| tty->print("c2-osr"); |
| } |
| tty->print(" status="); |
| if (mh->queued_for_compilation()) { |
| tty->print("in-queue"); |
| } else tty->print("idle"); |
| } |
| tty->print_cr("]"); |
| } |
| |
| void TieredThresholdPolicy::initialize() { |
| int count = CICompilerCount; |
| bool c1_only = TieredStopAtLevel < CompLevel_full_optimization; |
| #ifdef _LP64 |
| // Turn on ergonomic compiler count selection |
| if (FLAG_IS_DEFAULT(CICompilerCountPerCPU) && FLAG_IS_DEFAULT(CICompilerCount)) { |
| FLAG_SET_DEFAULT(CICompilerCountPerCPU, true); |
| } |
| if (CICompilerCountPerCPU) { |
| // Simple log n seems to grow too slowly for tiered, try something faster: log n * log log n |
| int log_cpu = log2_int(os::active_processor_count()); |
| int loglog_cpu = log2_int(MAX2(log_cpu, 1)); |
| count = MAX2(log_cpu * loglog_cpu * 3 / 2, 2); |
| // Make sure there is enough space in the code cache to hold all the compiler buffers |
| size_t c1_size = Compiler::code_buffer_size(); |
| size_t c2_size = C2Compiler::initial_code_buffer_size(); |
| size_t buffer_size = c1_only ? c1_size : (c1_size/3 + 2*c2_size/3); |
| int max_count = (ReservedCodeCacheSize - (CodeCacheMinimumUseSpace DEBUG_ONLY(* 3))) / (int)buffer_size; |
| if (count > max_count) { |
| // Lower the compiler count such that all buffers fit into the code cache |
| count = MAX2(max_count, c1_only ? 1 : 2); |
| } |
| FLAG_SET_ERGO(intx, CICompilerCount, count); |
| } |
| #else |
| // On 32-bit systems, the number of compiler threads is limited to 3. |
| // On these systems, the virtual address space available to the JVM |
| // is usually limited to 2-4 GB (the exact value depends on the platform). |
| // As the compilers (especially C2) can consume a large amount of |
| // memory, scaling the number of compiler threads with the number of |
| // available cores can result in the exhaustion of the address space |
| /// available to the VM and thus cause the VM to crash. |
| if (FLAG_IS_DEFAULT(CICompilerCount)) { |
| count = 3; |
| FLAG_SET_ERGO(intx, CICompilerCount, count); |
| } |
| #endif |
| |
| if (c1_only) { |
| // No C2 compiler thread required |
| set_c1_count(count); |
| } else { |
| set_c1_count(MAX2(count / 3, 1)); |
| set_c2_count(MAX2(count - c1_count(), 1)); |
| } |
| assert(count == c1_count() + c2_count(), "inconsistent compiler thread count"); |
| |
| // Some inlining tuning |
| #ifdef X86 |
| if (FLAG_IS_DEFAULT(InlineSmallCode)) { |
| FLAG_SET_DEFAULT(InlineSmallCode, 2000); |
| } |
| #endif |
| |
| #if defined SPARC || defined AARCH64 |
| if (FLAG_IS_DEFAULT(InlineSmallCode)) { |
| FLAG_SET_DEFAULT(InlineSmallCode, 2500); |
| } |
| #endif |
| |
| set_increase_threshold_at_ratio(); |
| set_start_time(os::javaTimeMillis()); |
| } |
| |
| void TieredThresholdPolicy::set_carry_if_necessary(InvocationCounter *counter) { |
| if (!counter->carry() && counter->count() > InvocationCounter::count_limit / 2) { |
| counter->set_carry_flag(); |
| } |
| } |
| |
| // Set carry flags on the counters if necessary |
| void TieredThresholdPolicy::handle_counter_overflow(Method* method) { |
| MethodCounters *mcs = method->method_counters(); |
| if (mcs != NULL) { |
| set_carry_if_necessary(mcs->invocation_counter()); |
| set_carry_if_necessary(mcs->backedge_counter()); |
| } |
| MethodData* mdo = method->method_data(); |
| if (mdo != NULL) { |
| set_carry_if_necessary(mdo->invocation_counter()); |
| set_carry_if_necessary(mdo->backedge_counter()); |
| } |
| } |
| |
| // Called with the queue locked and with at least one element |
| CompileTask* TieredThresholdPolicy::select_task(CompileQueue* compile_queue) { |
| CompileTask *max_blocking_task = NULL; |
| CompileTask *max_task = NULL; |
| Method* max_method = NULL; |
| jlong t = os::javaTimeMillis(); |
| // Iterate through the queue and find a method with a maximum rate. |
| for (CompileTask* task = compile_queue->first(); task != NULL;) { |
| CompileTask* next_task = task->next(); |
| Method* method = task->method(); |
| update_rate(t, method); |
| if (max_task == NULL) { |
| max_task = task; |
| max_method = method; |
| } else { |
| // If a method has been stale for some time, remove it from the queue. |
| // Blocking tasks and tasks submitted from whitebox API don't become stale |
| if (task->can_become_stale() && is_stale(t, TieredCompileTaskTimeout, method) && !is_old(method)) { |
| if (PrintTieredEvents) { |
| print_event(REMOVE_FROM_QUEUE, method, method, task->osr_bci(), (CompLevel)task->comp_level()); |
| } |
| compile_queue->remove_and_mark_stale(task); |
| method->clear_queued_for_compilation(); |
| task = next_task; |
| continue; |
| } |
| |
| // Select a method with a higher rate |
| if (compare_methods(method, max_method)) { |
| max_task = task; |
| max_method = method; |
| } |
| } |
| |
| if (task->is_blocking()) { |
| if (max_blocking_task == NULL || compare_methods(method, max_blocking_task->method())) { |
| max_blocking_task = task; |
| } |
| } |
| |
| task = next_task; |
| } |
| |
| if (max_blocking_task != NULL) { |
| // In blocking compilation mode, the CompileBroker will make |
| // compilations submitted by a JVMCI compiler thread non-blocking. These |
| // compilations should be scheduled after all blocking compilations |
| // to service non-compiler related compilations sooner and reduce the |
| // chance of such compilations timing out. |
| max_task = max_blocking_task; |
| max_method = max_task->method(); |
| } |
| |
| if (max_task != NULL && max_task->comp_level() == CompLevel_full_profile && |
| TieredStopAtLevel > CompLevel_full_profile && |
| max_method != NULL && is_method_profiled(max_method)) { |
| max_task->set_comp_level(CompLevel_limited_profile); |
| |
| if (CompileBroker::compilation_is_complete(max_method, max_task->osr_bci(), CompLevel_limited_profile)) { |
| if (PrintTieredEvents) { |
| print_event(REMOVE_FROM_QUEUE, max_method, max_method, max_task->osr_bci(), (CompLevel)max_task->comp_level()); |
| } |
| compile_queue->remove_and_mark_stale(max_task); |
| max_method->clear_queued_for_compilation(); |
| return NULL; |
| } |
| |
| if (PrintTieredEvents) { |
| print_event(UPDATE_IN_QUEUE, max_method, max_method, max_task->osr_bci(), (CompLevel)max_task->comp_level()); |
| } |
| } |
| |
| return max_task; |
| } |
| |
| void TieredThresholdPolicy::reprofile(ScopeDesc* trap_scope, bool is_osr) { |
| for (ScopeDesc* sd = trap_scope;; sd = sd->sender()) { |
| if (PrintTieredEvents) { |
| methodHandle mh(sd->method()); |
| print_event(REPROFILE, mh, mh, InvocationEntryBci, CompLevel_none); |
| } |
| MethodData* mdo = sd->method()->method_data(); |
| if (mdo != NULL) { |
| mdo->reset_start_counters(); |
| } |
| if (sd->is_top()) break; |
| } |
| } |
| |
| nmethod* TieredThresholdPolicy::event(const methodHandle& method, const methodHandle& inlinee, |
| int branch_bci, int bci, CompLevel comp_level, CompiledMethod* nm, JavaThread* thread) { |
| if (comp_level == CompLevel_none && |
| JvmtiExport::can_post_interpreter_events() && |
| thread->is_interp_only_mode()) { |
| return NULL; |
| } |
| if (CompileTheWorld || ReplayCompiles) { |
| // Don't trigger other compiles in testing mode |
| return NULL; |
| } |
| |
| handle_counter_overflow(method()); |
| if (method() != inlinee()) { |
| handle_counter_overflow(inlinee()); |
| } |
| |
| if (PrintTieredEvents) { |
| print_event(bci == InvocationEntryBci ? CALL : LOOP, method, inlinee, bci, comp_level); |
| } |
| |
| if (bci == InvocationEntryBci) { |
| method_invocation_event(method, inlinee, comp_level, nm, thread); |
| } else { |
| // method == inlinee if the event originated in the main method |
| method_back_branch_event(method, inlinee, bci, comp_level, nm, thread); |
| // Check if event led to a higher level OSR compilation |
| nmethod* osr_nm = inlinee->lookup_osr_nmethod_for(bci, comp_level, false); |
| if (osr_nm != NULL && osr_nm->comp_level() > comp_level) { |
| // Perform OSR with new nmethod |
| return osr_nm; |
| } |
| } |
| return NULL; |
| } |
| |
| // Check if the method can be compiled, change level if necessary |
| void TieredThresholdPolicy::compile(const methodHandle& mh, int bci, CompLevel level, JavaThread* thread) { |
| assert(level <= TieredStopAtLevel, "Invalid compilation level"); |
| if (level == CompLevel_none) { |
| return; |
| } |
| if (level == CompLevel_aot) { |
| if (mh->has_aot_code()) { |
| if (PrintTieredEvents) { |
| print_event(COMPILE, mh, mh, bci, level); |
| } |
| MutexLocker ml(Compile_lock); |
| NoSafepointVerifier nsv; |
| if (mh->has_aot_code() && mh->code() != mh->aot_code()) { |
| mh->aot_code()->make_entrant(); |
| if (mh->has_compiled_code()) { |
| mh->code()->make_not_entrant(); |
| } |
| Method::set_code(mh, mh->aot_code()); |
| } |
| } |
| return; |
| } |
| |
| // Check if the method can be compiled. If it cannot be compiled with C1, continue profiling |
| // in the interpreter and then compile with C2 (the transition function will request that, |
| // see common() ). If the method cannot be compiled with C2 but still can with C1, compile it with |
| // pure C1. |
| if (!can_be_compiled(mh, level)) { |
| if (level == CompLevel_full_optimization && can_be_compiled(mh, CompLevel_simple)) { |
| compile(mh, bci, CompLevel_simple, thread); |
| } |
| return; |
| } |
| if (bci != InvocationEntryBci && mh->is_not_osr_compilable(level)) { |
| return; |
| } |
| if (!CompileBroker::compilation_is_in_queue(mh)) { |
| if (PrintTieredEvents) { |
| print_event(COMPILE, mh, mh, bci, level); |
| } |
| submit_compile(mh, bci, level, thread); |
| } |
| } |
| |
| // Update the rate and submit compile |
| void TieredThresholdPolicy::submit_compile(const methodHandle& mh, int bci, CompLevel level, JavaThread* thread) { |
| int hot_count = (bci == InvocationEntryBci) ? mh->invocation_count() : mh->backedge_count(); |
| update_rate(os::javaTimeMillis(), mh()); |
| CompileBroker::compile_method(mh, bci, level, mh, hot_count, CompileTask::Reason_Tiered, thread); |
| } |
| |
| // Print an event. |
| void TieredThresholdPolicy::print_specific(EventType type, const methodHandle& mh, const methodHandle& imh, |
| int bci, CompLevel level) { |
| tty->print(" rate="); |
| if (mh->prev_time() == 0) tty->print("n/a"); |
| else tty->print("%f", mh->rate()); |
| |
| tty->print(" k=%.2lf,%.2lf", threshold_scale(CompLevel_full_profile, Tier3LoadFeedback), |
| threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback)); |
| |
| } |
| |
| // update_rate() is called from select_task() while holding a compile queue lock. |
| void TieredThresholdPolicy::update_rate(jlong t, Method* m) { |
| // Skip update if counters are absent. |
| // Can't allocate them since we are holding compile queue lock. |
| if (m->method_counters() == NULL) return; |
| |
| if (is_old(m)) { |
| // We don't remove old methods from the queue, |
| // so we can just zero the rate. |
| m->set_rate(0); |
| return; |
| } |
| |
| // We don't update the rate if we've just came out of a safepoint. |
| // delta_s is the time since last safepoint in milliseconds. |
| jlong delta_s = t - SafepointSynchronize::end_of_last_safepoint(); |
| jlong delta_t = t - (m->prev_time() != 0 ? m->prev_time() : start_time()); // milliseconds since the last measurement |
| // How many events were there since the last time? |
| int event_count = m->invocation_count() + m->backedge_count(); |
| int delta_e = event_count - m->prev_event_count(); |
| |
| // We should be running for at least 1ms. |
| if (delta_s >= TieredRateUpdateMinTime) { |
| // And we must've taken the previous point at least 1ms before. |
| if (delta_t >= TieredRateUpdateMinTime && delta_e > 0) { |
| m->set_prev_time(t); |
| m->set_prev_event_count(event_count); |
| m->set_rate((float)delta_e / (float)delta_t); // Rate is events per millisecond |
| } else { |
| if (delta_t > TieredRateUpdateMaxTime && delta_e == 0) { |
| // If nothing happened for 25ms, zero the rate. Don't modify prev values. |
| m->set_rate(0); |
| } |
| } |
| } |
| } |
| |
| // Check if this method has been stale from a given number of milliseconds. |
| // See select_task(). |
| bool TieredThresholdPolicy::is_stale(jlong t, jlong timeout, Method* m) { |
| jlong delta_s = t - SafepointSynchronize::end_of_last_safepoint(); |
| jlong delta_t = t - m->prev_time(); |
| if (delta_t > timeout && delta_s > timeout) { |
| int event_count = m->invocation_count() + m->backedge_count(); |
| int delta_e = event_count - m->prev_event_count(); |
| // Return true if there were no events. |
| return delta_e == 0; |
| } |
| return false; |
| } |
| |
| // We don't remove old methods from the compile queue even if they have |
| // very low activity. See select_task(). |
| bool TieredThresholdPolicy::is_old(Method* method) { |
| return method->invocation_count() > 50000 || method->backedge_count() > 500000; |
| } |
| |
| double TieredThresholdPolicy::weight(Method* method) { |
| return (double)(method->rate() + 1) * |
| (method->invocation_count() + 1) * (method->backedge_count() + 1); |
| } |
| |
| // Apply heuristics and return true if x should be compiled before y |
| bool TieredThresholdPolicy::compare_methods(Method* x, Method* y) { |
| if (x->highest_comp_level() > y->highest_comp_level()) { |
| // recompilation after deopt |
| return true; |
| } else |
| if (x->highest_comp_level() == y->highest_comp_level()) { |
| if (weight(x) > weight(y)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| // Is method profiled enough? |
| bool TieredThresholdPolicy::is_method_profiled(Method* method) { |
| MethodData* mdo = method->method_data(); |
| if (mdo != NULL) { |
| int i = mdo->invocation_count_delta(); |
| int b = mdo->backedge_count_delta(); |
| return call_predicate_helper<CompLevel_full_profile>(i, b, 1, method); |
| } |
| return false; |
| } |
| |
| double TieredThresholdPolicy::threshold_scale(CompLevel level, int feedback_k) { |
| double queue_size = CompileBroker::queue_size(level); |
| int comp_count = compiler_count(level); |
| double k = queue_size / (feedback_k * comp_count) + 1; |
| |
| // Increase C1 compile threshold when the code cache is filled more |
| // than specified by IncreaseFirstTierCompileThresholdAt percentage. |
| // The main intention is to keep enough free space for C2 compiled code |
| // to achieve peak performance if the code cache is under stress. |
| if ((TieredStopAtLevel == CompLevel_full_optimization) && (level != CompLevel_full_optimization)) { |
| double current_reverse_free_ratio = CodeCache::reverse_free_ratio(CodeCache::get_code_blob_type(level)); |
| if (current_reverse_free_ratio > _increase_threshold_at_ratio) { |
| k *= exp(current_reverse_free_ratio - _increase_threshold_at_ratio); |
| } |
| } |
| return k; |
| } |
| |
| // Call and loop predicates determine whether a transition to a higher |
| // compilation level should be performed (pointers to predicate functions |
| // are passed to common()). |
| // Tier?LoadFeedback is basically a coefficient that determines of |
| // how many methods per compiler thread can be in the queue before |
| // the threshold values double. |
| bool TieredThresholdPolicy::loop_predicate(int i, int b, CompLevel cur_level, Method* method) { |
| switch(cur_level) { |
| case CompLevel_aot: { |
| double k = threshold_scale(CompLevel_full_profile, Tier3LoadFeedback); |
| return loop_predicate_helper<CompLevel_aot>(i, b, k, method); |
| } |
| case CompLevel_none: |
| case CompLevel_limited_profile: { |
| double k = threshold_scale(CompLevel_full_profile, Tier3LoadFeedback); |
| return loop_predicate_helper<CompLevel_none>(i, b, k, method); |
| } |
| case CompLevel_full_profile: { |
| double k = threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback); |
| return loop_predicate_helper<CompLevel_full_profile>(i, b, k, method); |
| } |
| default: |
| return true; |
| } |
| } |
| |
| bool TieredThresholdPolicy::call_predicate(int i, int b, CompLevel cur_level, Method* method) { |
| switch(cur_level) { |
| case CompLevel_aot: { |
| double k = threshold_scale(CompLevel_full_profile, Tier3LoadFeedback); |
| return call_predicate_helper<CompLevel_aot>(i, b, k, method); |
| } |
| case CompLevel_none: |
| case CompLevel_limited_profile: { |
| double k = threshold_scale(CompLevel_full_profile, Tier3LoadFeedback); |
| return call_predicate_helper<CompLevel_none>(i, b, k, method); |
| } |
| case CompLevel_full_profile: { |
| double k = threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback); |
| return call_predicate_helper<CompLevel_full_profile>(i, b, k, method); |
| } |
| default: |
| return true; |
| } |
| } |
| |
| // Determine is a method is mature. |
| bool TieredThresholdPolicy::is_mature(Method* method) { |
| if (is_trivial(method)) return true; |
| MethodData* mdo = method->method_data(); |
| if (mdo != NULL) { |
| int i = mdo->invocation_count(); |
| int b = mdo->backedge_count(); |
| double k = ProfileMaturityPercentage / 100.0; |
| return call_predicate_helper<CompLevel_full_profile>(i, b, k, method) || |
| loop_predicate_helper<CompLevel_full_profile>(i, b, k, method); |
| } |
| return false; |
| } |
| |
| // If a method is old enough and is still in the interpreter we would want to |
| // start profiling without waiting for the compiled method to arrive. |
| // We also take the load on compilers into the account. |
| bool TieredThresholdPolicy::should_create_mdo(Method* method, CompLevel cur_level) { |
| if (cur_level == CompLevel_none && |
| CompileBroker::queue_size(CompLevel_full_optimization) <= |
| Tier3DelayOn * compiler_count(CompLevel_full_optimization)) { |
| int i = method->invocation_count(); |
| int b = method->backedge_count(); |
| double k = Tier0ProfilingStartPercentage / 100.0; |
| return call_predicate_helper<CompLevel_none>(i, b, k, method) || loop_predicate_helper<CompLevel_none>(i, b, k, method); |
| } |
| return false; |
| } |
| |
| // Inlining control: if we're compiling a profiled method with C1 and the callee |
| // is known to have OSRed in a C2 version, don't inline it. |
| bool TieredThresholdPolicy::should_not_inline(ciEnv* env, ciMethod* callee) { |
| CompLevel comp_level = (CompLevel)env->comp_level(); |
| if (comp_level == CompLevel_full_profile || |
| comp_level == CompLevel_limited_profile) { |
| return callee->highest_osr_comp_level() == CompLevel_full_optimization; |
| } |
| return false; |
| } |
| |
| // Create MDO if necessary. |
| void TieredThresholdPolicy::create_mdo(const methodHandle& mh, JavaThread* THREAD) { |
| if (mh->is_native() || |
| mh->is_abstract() || |
| mh->is_accessor() || |
| mh->is_constant_getter()) { |
| return; |
| } |
| if (mh->method_data() == NULL) { |
| Method::build_interpreter_method_data(mh, CHECK_AND_CLEAR); |
| } |
| } |
| |
| |
| /* |
| * Method states: |
| * 0 - interpreter (CompLevel_none) |
| * 1 - pure C1 (CompLevel_simple) |
| * 2 - C1 with invocation and backedge counting (CompLevel_limited_profile) |
| * 3 - C1 with full profiling (CompLevel_full_profile) |
| * 4 - C2 (CompLevel_full_optimization) |
| * |
| * Common state transition patterns: |
| * a. 0 -> 3 -> 4. |
| * The most common path. But note that even in this straightforward case |
| * profiling can start at level 0 and finish at level 3. |
| * |
| * b. 0 -> 2 -> 3 -> 4. |
| * This case occurs when the load on C2 is deemed too high. So, instead of transitioning |
| * into state 3 directly and over-profiling while a method is in the C2 queue we transition to |
| * level 2 and wait until the load on C2 decreases. This path is disabled for OSRs. |
| * |
| * c. 0 -> (3->2) -> 4. |
| * In this case we enqueue a method for compilation at level 3, but the C1 queue is long enough |
| * to enable the profiling to fully occur at level 0. In this case we change the compilation level |
| * of the method to 2 while the request is still in-queue, because it'll allow it to run much faster |
| * without full profiling while c2 is compiling. |
| * |
| * d. 0 -> 3 -> 1 or 0 -> 2 -> 1. |
| * After a method was once compiled with C1 it can be identified as trivial and be compiled to |
| * level 1. These transition can also occur if a method can't be compiled with C2 but can with C1. |
| * |
| * e. 0 -> 4. |
| * This can happen if a method fails C1 compilation (it will still be profiled in the interpreter) |
| * or because of a deopt that didn't require reprofiling (compilation won't happen in this case because |
| * the compiled version already exists). |
| * |
| * Note that since state 0 can be reached from any other state via deoptimization different loops |
| * are possible. |
| * |
| */ |
| |
| // Common transition function. Given a predicate determines if a method should transition to another level. |
| CompLevel TieredThresholdPolicy::common(Predicate p, Method* method, CompLevel cur_level, bool disable_feedback) { |
| CompLevel next_level = cur_level; |
| int i = method->invocation_count(); |
| int b = method->backedge_count(); |
| |
| if (is_trivial(method)) { |
| next_level = CompLevel_simple; |
| } else { |
| switch(cur_level) { |
| default: break; |
| case CompLevel_aot: { |
| // If we were at full profile level, would we switch to full opt? |
| if (common(p, method, CompLevel_full_profile, disable_feedback) == CompLevel_full_optimization) { |
| next_level = CompLevel_full_optimization; |
| } else if (disable_feedback || (CompileBroker::queue_size(CompLevel_full_optimization) <= |
| Tier3DelayOff * compiler_count(CompLevel_full_optimization) && |
| (this->*p)(i, b, cur_level, method))) { |
| next_level = CompLevel_full_profile; |
| } |
| } |
| break; |
| case CompLevel_none: |
| // If we were at full profile level, would we switch to full opt? |
| if (common(p, method, CompLevel_full_profile, disable_feedback) == CompLevel_full_optimization) { |
| next_level = CompLevel_full_optimization; |
| } else if ((this->*p)(i, b, cur_level, method)) { |
| #if INCLUDE_JVMCI |
| if (EnableJVMCI && UseJVMCICompiler) { |
| // Since JVMCI takes a while to warm up, its queue inevitably backs up during |
| // early VM execution. As of 2014-06-13, JVMCI's inliner assumes that the root |
| // compilation method and all potential inlinees have mature profiles (which |
| // includes type profiling). If it sees immature profiles, JVMCI's inliner |
| // can perform pathologically bad (e.g., causing OutOfMemoryErrors due to |
| // exploring/inlining too many graphs). Since a rewrite of the inliner is |
| // in progress, we simply disable the dialing back heuristic for now and will |
| // revisit this decision once the new inliner is completed. |
| next_level = CompLevel_full_profile; |
| } else |
| #endif |
| { |
| // C1-generated fully profiled code is about 30% slower than the limited profile |
| // code that has only invocation and backedge counters. The observation is that |
| // if C2 queue is large enough we can spend too much time in the fully profiled code |
| // while waiting for C2 to pick the method from the queue. To alleviate this problem |
| // we introduce a feedback on the C2 queue size. If the C2 queue is sufficiently long |
| // we choose to compile a limited profiled version and then recompile with full profiling |
| // when the load on C2 goes down. |
| if (!disable_feedback && CompileBroker::queue_size(CompLevel_full_optimization) > |
| Tier3DelayOn * compiler_count(CompLevel_full_optimization)) { |
| next_level = CompLevel_limited_profile; |
| } else { |
| next_level = CompLevel_full_profile; |
| } |
| } |
| } |
| break; |
| case CompLevel_limited_profile: |
| if (is_method_profiled(method)) { |
| // Special case: we got here because this method was fully profiled in the interpreter. |
| next_level = CompLevel_full_optimization; |
| } else { |
| MethodData* mdo = method->method_data(); |
| if (mdo != NULL) { |
| if (mdo->would_profile()) { |
| if (disable_feedback || (CompileBroker::queue_size(CompLevel_full_optimization) <= |
| Tier3DelayOff * compiler_count(CompLevel_full_optimization) && |
| (this->*p)(i, b, cur_level, method))) { |
| next_level = CompLevel_full_profile; |
| } |
| } else { |
| next_level = CompLevel_full_optimization; |
| } |
| } else { |
| // If there is no MDO we need to profile |
| if (disable_feedback || (CompileBroker::queue_size(CompLevel_full_optimization) <= |
| Tier3DelayOff * compiler_count(CompLevel_full_optimization) && |
| (this->*p)(i, b, cur_level, method))) { |
| next_level = CompLevel_full_profile; |
| } |
| } |
| } |
| break; |
| case CompLevel_full_profile: |
| { |
| MethodData* mdo = method->method_data(); |
| if (mdo != NULL) { |
| if (mdo->would_profile()) { |
| int mdo_i = mdo->invocation_count_delta(); |
| int mdo_b = mdo->backedge_count_delta(); |
| if ((this->*p)(mdo_i, mdo_b, cur_level, method)) { |
| next_level = CompLevel_full_optimization; |
| } |
| } else { |
| next_level = CompLevel_full_optimization; |
| } |
| } |
| } |
| break; |
| } |
| } |
| return MIN2(next_level, (CompLevel)TieredStopAtLevel); |
| } |
| |
| // Determine if a method should be compiled with a normal entry point at a different level. |
| CompLevel TieredThresholdPolicy::call_event(Method* method, CompLevel cur_level, JavaThread * thread) { |
| CompLevel osr_level = MIN2((CompLevel) method->highest_osr_comp_level(), |
| common(&TieredThresholdPolicy::loop_predicate, method, cur_level, true)); |
| CompLevel next_level = common(&TieredThresholdPolicy::call_predicate, method, cur_level); |
| |
| // If OSR method level is greater than the regular method level, the levels should be |
| // equalized by raising the regular method level in order to avoid OSRs during each |
| // invocation of the method. |
| if (osr_level == CompLevel_full_optimization && cur_level == CompLevel_full_profile) { |
| MethodData* mdo = method->method_data(); |
| guarantee(mdo != NULL, "MDO should not be NULL"); |
| if (mdo->invocation_count() >= 1) { |
| next_level = CompLevel_full_optimization; |
| } |
| } else { |
| next_level = MAX2(osr_level, next_level); |
| } |
| #if INCLUDE_JVMCI |
| if (UseJVMCICompiler) { |
| next_level = JVMCIRuntime::adjust_comp_level(method, false, next_level, thread); |
| } |
| #endif |
| return next_level; |
| } |
| |
| // Determine if we should do an OSR compilation of a given method. |
| CompLevel TieredThresholdPolicy::loop_event(Method* method, CompLevel cur_level, JavaThread* thread) { |
| CompLevel next_level = common(&TieredThresholdPolicy::loop_predicate, method, cur_level, true); |
| if (cur_level == CompLevel_none) { |
| // If there is a live OSR method that means that we deopted to the interpreter |
| // for the transition. |
| CompLevel osr_level = MIN2((CompLevel)method->highest_osr_comp_level(), next_level); |
| if (osr_level > CompLevel_none) { |
| return osr_level; |
| } |
| } |
| #if INCLUDE_JVMCI |
| if (UseJVMCICompiler) { |
| next_level = JVMCIRuntime::adjust_comp_level(method, true, next_level, thread); |
| } |
| #endif |
| return next_level; |
| } |
| |
| bool TieredThresholdPolicy::maybe_switch_to_aot(const methodHandle& mh, CompLevel cur_level, CompLevel next_level, JavaThread* thread) { |
| if (UseAOT && !delay_compilation_during_startup()) { |
| if (cur_level == CompLevel_full_profile || cur_level == CompLevel_none) { |
| // If the current level is full profile or interpreter and we're switching to any other level, |
| // activate the AOT code back first so that we won't waste time overprofiling. |
| compile(mh, InvocationEntryBci, CompLevel_aot, thread); |
| // Fall through for JIT compilation. |
| } |
| if (next_level == CompLevel_limited_profile && cur_level != CompLevel_aot && mh->has_aot_code()) { |
| // If the next level is limited profile, use the aot code (if there is any), |
| // since it's essentially the same thing. |
| compile(mh, InvocationEntryBci, CompLevel_aot, thread); |
| // Not need to JIT, we're done. |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| |
| // Handle the invocation event. |
| void TieredThresholdPolicy::method_invocation_event(const methodHandle& mh, const methodHandle& imh, |
| CompLevel level, CompiledMethod* nm, JavaThread* thread) { |
| if (should_create_mdo(mh(), level)) { |
| create_mdo(mh, thread); |
| } |
| CompLevel next_level = call_event(mh(), level, thread); |
| if (next_level != level) { |
| if (maybe_switch_to_aot(mh, level, next_level, thread)) { |
| // No JITting necessary |
| return; |
| } |
| if (is_compilation_enabled() && !CompileBroker::compilation_is_in_queue(mh)) { |
| compile(mh, InvocationEntryBci, next_level, thread); |
| } |
| } |
| } |
| |
| // Handle the back branch event. Notice that we can compile the method |
| // with a regular entry from here. |
| void TieredThresholdPolicy::method_back_branch_event(const methodHandle& mh, const methodHandle& imh, |
| int bci, CompLevel level, CompiledMethod* nm, JavaThread* thread) { |
| if (should_create_mdo(mh(), level)) { |
| create_mdo(mh, thread); |
| } |
| // Check if MDO should be created for the inlined method |
| if (should_create_mdo(imh(), level)) { |
| create_mdo(imh, thread); |
| } |
| |
| if (is_compilation_enabled()) { |
| CompLevel next_osr_level = loop_event(imh(), level, thread); |
| CompLevel max_osr_level = (CompLevel)imh->highest_osr_comp_level(); |
| // At the very least compile the OSR version |
| if (!CompileBroker::compilation_is_in_queue(imh) && (next_osr_level != level)) { |
| compile(imh, bci, next_osr_level, thread); |
| } |
| |
| // Use loop event as an opportunity to also check if there's been |
| // enough calls. |
| CompLevel cur_level, next_level; |
| if (mh() != imh()) { // If there is an enclosing method |
| if (level == CompLevel_aot) { |
| // Recompile the enclosing method to prevent infinite OSRs. Stay at AOT level while it's compiling. |
| if (max_osr_level != CompLevel_none && !CompileBroker::compilation_is_in_queue(mh)) { |
| compile(mh, InvocationEntryBci, MIN2((CompLevel)TieredStopAtLevel, CompLevel_full_profile), thread); |
| } |
| } else { |
| // Current loop event level is not AOT |
| guarantee(nm != NULL, "Should have nmethod here"); |
| cur_level = comp_level(mh()); |
| next_level = call_event(mh(), cur_level, thread); |
| |
| if (max_osr_level == CompLevel_full_optimization) { |
| // The inlinee OSRed to full opt, we need to modify the enclosing method to avoid deopts |
| bool make_not_entrant = false; |
| if (nm->is_osr_method()) { |
| // This is an osr method, just make it not entrant and recompile later if needed |
| make_not_entrant = true; |
| } else { |
| if (next_level != CompLevel_full_optimization) { |
| // next_level is not full opt, so we need to recompile the |
| // enclosing method without the inlinee |
| cur_level = CompLevel_none; |
| make_not_entrant = true; |
| } |
| } |
| if (make_not_entrant) { |
| if (PrintTieredEvents) { |
| int osr_bci = nm->is_osr_method() ? nm->osr_entry_bci() : InvocationEntryBci; |
| print_event(MAKE_NOT_ENTRANT, mh(), mh(), osr_bci, level); |
| } |
| nm->make_not_entrant(); |
| } |
| } |
| // Fix up next_level if necessary to avoid deopts |
| if (next_level == CompLevel_limited_profile && max_osr_level == CompLevel_full_profile) { |
| next_level = CompLevel_full_profile; |
| } |
| if (cur_level != next_level) { |
| if (!maybe_switch_to_aot(mh, cur_level, next_level, thread) && !CompileBroker::compilation_is_in_queue(mh)) { |
| compile(mh, InvocationEntryBci, next_level, thread); |
| } |
| } |
| } |
| } else { |
| cur_level = comp_level(mh()); |
| next_level = call_event(mh(), cur_level, thread); |
| if (next_level != cur_level) { |
| if (!maybe_switch_to_aot(mh, cur_level, next_level, thread) && !CompileBroker::compilation_is_in_queue(mh)) { |
| compile(mh, InvocationEntryBci, next_level, thread); |
| } |
| } |
| } |
| } |
| } |
| |
| #endif |
