diff -r 496bbf554c5c -r 38176d1c5ec2 src/hotspot/share/runtime/compilationPolicy.cpp --- a/src/hotspot/share/runtime/compilationPolicy.cpp Wed Oct 16 01:16:12 2019 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,506 +0,0 @@ -/* - * Copyright (c) 2000, 2019, 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 "classfile/classLoaderDataGraph.inline.hpp" -#include "code/compiledIC.hpp" -#include "code/nmethod.hpp" -#include "code/scopeDesc.hpp" -#include "interpreter/interpreter.hpp" -#include "memory/resourceArea.hpp" -#include "oops/methodData.hpp" -#include "oops/method.inline.hpp" -#include "oops/oop.inline.hpp" -#include "prims/nativeLookup.hpp" -#include "runtime/compilationPolicy.hpp" -#include "runtime/frame.hpp" -#include "runtime/handles.inline.hpp" -#include "runtime/stubRoutines.hpp" -#include "runtime/thread.hpp" -#include "runtime/tieredThresholdPolicy.hpp" -#include "runtime/vframe.hpp" -#include "runtime/vmOperations.hpp" -#include "utilities/events.hpp" -#include "utilities/globalDefinitions.hpp" - -#ifdef COMPILER1 -#include "c1/c1_Compiler.hpp" -#endif -#ifdef COMPILER2 -#include "opto/c2compiler.hpp" -#endif - -CompilationPolicy* CompilationPolicy::_policy; - -// Determine compilation policy based on command line argument -void compilationPolicy_init() { - #ifdef TIERED - if (TieredCompilation) { - CompilationPolicy::set_policy(new TieredThresholdPolicy()); - } else { - CompilationPolicy::set_policy(new SimpleCompPolicy()); - } - #else - CompilationPolicy::set_policy(new SimpleCompPolicy()); - #endif - - CompilationPolicy::policy()->initialize(); -} - -// Returns true if m must be compiled before executing it -// This is intended to force compiles for methods (usually for -// debugging) that would otherwise be interpreted for some reason. -bool CompilationPolicy::must_be_compiled(const methodHandle& m, int comp_level) { - // Don't allow Xcomp to cause compiles in replay mode - if (ReplayCompiles) return false; - - if (m->has_compiled_code()) return false; // already compiled - if (!can_be_compiled(m, comp_level)) return false; - - return !UseInterpreter || // must compile all methods - (UseCompiler && AlwaysCompileLoopMethods && m->has_loops() && CompileBroker::should_compile_new_jobs()); // eagerly compile loop methods -} - -void CompilationPolicy::compile_if_required(const methodHandle& selected_method, TRAPS) { - if (must_be_compiled(selected_method)) { - // This path is unusual, mostly used by the '-Xcomp' stress test mode. - - // Note: with several active threads, the must_be_compiled may be true - // while can_be_compiled is false; remove assert - // assert(CompilationPolicy::can_be_compiled(selected_method), "cannot compile"); - if (!THREAD->can_call_java() || THREAD->is_Compiler_thread()) { - // don't force compilation, resolve was on behalf of compiler - return; - } - if (selected_method->method_holder()->is_not_initialized()) { - // 'is_not_initialized' means not only '!is_initialized', but also that - // initialization has not been started yet ('!being_initialized') - // Do not force compilation of methods in uninitialized classes. - // Note that doing this would throw an assert later, - // in CompileBroker::compile_method. - // We sometimes use the link resolver to do reflective lookups - // even before classes are initialized. - return; - } - CompileBroker::compile_method(selected_method, InvocationEntryBci, - CompilationPolicy::policy()->initial_compile_level(), - methodHandle(), 0, CompileTask::Reason_MustBeCompiled, CHECK); - } -} - -// Returns true if m is allowed to be compiled -bool CompilationPolicy::can_be_compiled(const methodHandle& m, int comp_level) { - // allow any levels for WhiteBox - assert(WhiteBoxAPI || comp_level == CompLevel_all || is_compile(comp_level), "illegal compilation level"); - - if (m->is_abstract()) return false; - if (DontCompileHugeMethods && m->code_size() > HugeMethodLimit) return false; - - // Math intrinsics should never be compiled as this can lead to - // monotonicity problems because the interpreter will prefer the - // compiled code to the intrinsic version. This can't happen in - // production because the invocation counter can't be incremented - // but we shouldn't expose the system to this problem in testing - // modes. - if (!AbstractInterpreter::can_be_compiled(m)) { - return false; - } - if (comp_level == CompLevel_all) { - if (TieredCompilation) { - // enough to be compilable at any level for tiered - return !m->is_not_compilable(CompLevel_simple) || !m->is_not_compilable(CompLevel_full_optimization); - } else { - // must be compilable at available level for non-tiered - return !m->is_not_compilable(CompLevel_highest_tier); - } - } else if (is_compile(comp_level)) { - return !m->is_not_compilable(comp_level); - } - return false; -} - -// Returns true if m is allowed to be osr compiled -bool CompilationPolicy::can_be_osr_compiled(const methodHandle& m, int comp_level) { - bool result = false; - if (comp_level == CompLevel_all) { - if (TieredCompilation) { - // enough to be osr compilable at any level for tiered - result = !m->is_not_osr_compilable(CompLevel_simple) || !m->is_not_osr_compilable(CompLevel_full_optimization); - } else { - // must be osr compilable at available level for non-tiered - result = !m->is_not_osr_compilable(CompLevel_highest_tier); - } - } else if (is_compile(comp_level)) { - result = !m->is_not_osr_compilable(comp_level); - } - return (result && can_be_compiled(m, comp_level)); -} - -bool CompilationPolicy::is_compilation_enabled() { - // NOTE: CompileBroker::should_compile_new_jobs() checks for UseCompiler - return CompileBroker::should_compile_new_jobs(); -} - -CompileTask* CompilationPolicy::select_task_helper(CompileQueue* compile_queue) { - // Remove unloaded methods from the queue - for (CompileTask* task = compile_queue->first(); task != NULL; ) { - CompileTask* next = task->next(); - if (task->is_unloaded()) { - compile_queue->remove_and_mark_stale(task); - } - task = next; - } -#if INCLUDE_JVMCI - if (UseJVMCICompiler && !BackgroundCompilation) { - /* - * 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. - */ - for (CompileTask* task = compile_queue->first(); task != NULL; task = task->next()) { - if (task->is_blocking()) { - return task; - } - } - } -#endif - return compile_queue->first(); -} - -#ifndef PRODUCT -void SimpleCompPolicy::trace_osr_completion(nmethod* osr_nm) { - if (TraceOnStackReplacement) { - if (osr_nm == NULL) tty->print_cr("compilation failed"); - else tty->print_cr("nmethod " INTPTR_FORMAT, p2i(osr_nm)); - } -} -#endif // !PRODUCT - -void SimpleCompPolicy::initialize() { - // Setup the compiler thread numbers - if (CICompilerCountPerCPU) { - // Example: if CICompilerCountPerCPU is true, then we get - // max(log2(8)-1,1) = 2 compiler threads on an 8-way machine. - // May help big-app startup time. - _compiler_count = MAX2(log2_int(os::active_processor_count())-1,1); - // Make sure there is enough space in the code cache to hold all the compiler buffers - size_t buffer_size = 1; -#ifdef COMPILER1 - buffer_size = is_client_compilation_mode_vm() ? Compiler::code_buffer_size() : buffer_size; -#endif -#ifdef COMPILER2 - buffer_size = is_server_compilation_mode_vm() ? C2Compiler::initial_code_buffer_size() : buffer_size; -#endif - int max_count = (ReservedCodeCacheSize - (CodeCacheMinimumUseSpace DEBUG_ONLY(* 3))) / (int)buffer_size; - if (_compiler_count > max_count) { - // Lower the compiler count such that all buffers fit into the code cache - _compiler_count = MAX2(max_count, 1); - } - FLAG_SET_ERGO(CICompilerCount, _compiler_count); - } else { - _compiler_count = CICompilerCount; - } -} - -// Note: this policy is used ONLY if TieredCompilation is off. -// compiler_count() behaves the following way: -// - with TIERED build (with both COMPILER1 and COMPILER2 defined) it should return -// zero for the c1 compilation levels in server compilation mode runs -// and c2 compilation levels in client compilation mode runs. -// - with COMPILER2 not defined it should return zero for c2 compilation levels. -// - with COMPILER1 not defined it should return zero for c1 compilation levels. -// - if neither is defined - always return zero. -int SimpleCompPolicy::compiler_count(CompLevel comp_level) { - assert(!TieredCompilation, "This policy should not be used with TieredCompilation"); - if (COMPILER2_PRESENT(is_server_compilation_mode_vm() && is_c2_compile(comp_level) ||) - is_client_compilation_mode_vm() && is_c1_compile(comp_level)) { - return _compiler_count; - } - return 0; -} - -void SimpleCompPolicy::reset_counter_for_invocation_event(const methodHandle& m) { - // Make sure invocation and backedge counter doesn't overflow again right away - // as would be the case for native methods. - - // BUT also make sure the method doesn't look like it was never executed. - // Set carry bit and reduce counter's value to min(count, CompileThreshold/2). - MethodCounters* mcs = m->method_counters(); - assert(mcs != NULL, "MethodCounters cannot be NULL for profiling"); - mcs->invocation_counter()->set_carry(); - mcs->backedge_counter()->set_carry(); - - assert(!m->was_never_executed(), "don't reset to 0 -- could be mistaken for never-executed"); -} - -void SimpleCompPolicy::reset_counter_for_back_branch_event(const methodHandle& m) { - // Delay next back-branch event but pump up invocation counter to trigger - // whole method compilation. - MethodCounters* mcs = m->method_counters(); - assert(mcs != NULL, "MethodCounters cannot be NULL for profiling"); - InvocationCounter* i = mcs->invocation_counter(); - InvocationCounter* b = mcs->backedge_counter(); - - // Don't set invocation_counter's value too low otherwise the method will - // look like immature (ic < ~5300) which prevents the inlining based on - // the type profiling. - i->set(i->state(), CompileThreshold); - // Don't reset counter too low - it is used to check if OSR method is ready. - b->set(b->state(), CompileThreshold / 2); -} - -// -// CounterDecay -// -// Iterates through invocation counters and decrements them. This -// is done at each safepoint. -// -class CounterDecay : public AllStatic { - static jlong _last_timestamp; - static void do_method(Method* m) { - MethodCounters* mcs = m->method_counters(); - if (mcs != NULL) { - mcs->invocation_counter()->decay(); - } - } -public: - static void decay(); - static bool is_decay_needed() { - return (os::javaTimeMillis() - _last_timestamp) > CounterDecayMinIntervalLength; - } -}; - -jlong CounterDecay::_last_timestamp = 0; - -void CounterDecay::decay() { - _last_timestamp = os::javaTimeMillis(); - - // This operation is going to be performed only at the end of a safepoint - // and hence GC's will not be going on, all Java mutators are suspended - // at this point and hence SystemDictionary_lock is also not needed. - assert(SafepointSynchronize::is_at_safepoint(), "can only be executed at a safepoint"); - size_t nclasses = ClassLoaderDataGraph::num_instance_classes(); - size_t classes_per_tick = nclasses * (CounterDecayMinIntervalLength * 1e-3 / - CounterHalfLifeTime); - for (size_t i = 0; i < classes_per_tick; i++) { - InstanceKlass* k = ClassLoaderDataGraph::try_get_next_class(); - if (k != NULL) { - k->methods_do(do_method); - } - } -} - -// Called at the end of the safepoint -void SimpleCompPolicy::do_safepoint_work() { - if(UseCounterDecay && CounterDecay::is_decay_needed()) { - CounterDecay::decay(); - } -} - -void SimpleCompPolicy::reprofile(ScopeDesc* trap_scope, bool is_osr) { - ScopeDesc* sd = trap_scope; - MethodCounters* mcs; - InvocationCounter* c; - for (; !sd->is_top(); sd = sd->sender()) { - mcs = sd->method()->method_counters(); - if (mcs != NULL) { - // Reset ICs of inlined methods, since they can trigger compilations also. - mcs->invocation_counter()->reset(); - } - } - mcs = sd->method()->method_counters(); - if (mcs != NULL) { - c = mcs->invocation_counter(); - if (is_osr) { - // It was an OSR method, so bump the count higher. - c->set(c->state(), CompileThreshold); - } else { - c->reset(); - } - mcs->backedge_counter()->reset(); - } -} - -// This method can be called by any component of the runtime to notify the policy -// that it's recommended to delay the compilation of this method. -void SimpleCompPolicy::delay_compilation(Method* method) { - MethodCounters* mcs = method->method_counters(); - if (mcs != NULL) { - mcs->invocation_counter()->decay(); - mcs->backedge_counter()->decay(); - } -} - -void SimpleCompPolicy::disable_compilation(Method* method) { - MethodCounters* mcs = method->method_counters(); - if (mcs != NULL) { - mcs->invocation_counter()->set_state(InvocationCounter::wait_for_nothing); - mcs->backedge_counter()->set_state(InvocationCounter::wait_for_nothing); - } -} - -CompileTask* SimpleCompPolicy::select_task(CompileQueue* compile_queue) { - return select_task_helper(compile_queue); -} - -bool SimpleCompPolicy::is_mature(Method* method) { - MethodData* mdo = method->method_data(); - assert(mdo != NULL, "Should be"); - uint current = mdo->mileage_of(method); - uint initial = mdo->creation_mileage(); - if (current < initial) - return true; // some sort of overflow - uint target; - if (ProfileMaturityPercentage <= 0) - target = (uint) -ProfileMaturityPercentage; // absolute value - else - target = (uint)( (ProfileMaturityPercentage * CompileThreshold) / 100 ); - return (current >= initial + target); -} - -nmethod* SimpleCompPolicy::event(const methodHandle& method, const methodHandle& inlinee, int branch_bci, - int bci, CompLevel comp_level, CompiledMethod* nm, JavaThread* thread) { - assert(comp_level == CompLevel_none, "This should be only called from the interpreter"); - NOT_PRODUCT(trace_frequency_counter_overflow(method, branch_bci, bci)); - if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) { - // If certain JVMTI events (e.g. frame pop event) are requested then the - // thread is forced to remain in interpreted code. This is - // implemented partly by a check in the run_compiled_code - // section of the interpreter whether we should skip running - // compiled code, and partly by skipping OSR compiles for - // interpreted-only threads. - if (bci != InvocationEntryBci) { - reset_counter_for_back_branch_event(method); - return NULL; - } - } - if (ReplayCompiles) { - // Don't trigger other compiles in testing mode - if (bci == InvocationEntryBci) { - reset_counter_for_invocation_event(method); - } else { - reset_counter_for_back_branch_event(method); - } - return NULL; - } - - if (bci == InvocationEntryBci) { - // when code cache is full, compilation gets switched off, UseCompiler - // is set to false - if (!method->has_compiled_code() && UseCompiler) { - method_invocation_event(method, thread); - } else { - // Force counter overflow on method entry, even if no compilation - // happened. (The method_invocation_event call does this also.) - reset_counter_for_invocation_event(method); - } - // compilation at an invocation overflow no longer goes and retries test for - // compiled method. We always run the loser of the race as interpreted. - // so return NULL - return NULL; - } else { - // counter overflow in a loop => try to do on-stack-replacement - nmethod* osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true); - NOT_PRODUCT(trace_osr_request(method, osr_nm, bci)); - // when code cache is full, we should not compile any more... - if (osr_nm == NULL && UseCompiler) { - method_back_branch_event(method, bci, thread); - osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true); - } - if (osr_nm == NULL) { - reset_counter_for_back_branch_event(method); - return NULL; - } - return osr_nm; - } - return NULL; -} - -#ifndef PRODUCT -void SimpleCompPolicy::trace_frequency_counter_overflow(const methodHandle& m, int branch_bci, int bci) { - if (TraceInvocationCounterOverflow) { - MethodCounters* mcs = m->method_counters(); - assert(mcs != NULL, "MethodCounters cannot be NULL for profiling"); - InvocationCounter* ic = mcs->invocation_counter(); - InvocationCounter* bc = mcs->backedge_counter(); - ResourceMark rm; - if (bci == InvocationEntryBci) { - tty->print("comp-policy cntr ovfl @ %d in entry of ", bci); - } else { - tty->print("comp-policy cntr ovfl @ %d in loop of ", bci); - } - m->print_value(); - tty->cr(); - ic->print(); - bc->print(); - if (ProfileInterpreter) { - if (bci != InvocationEntryBci) { - MethodData* mdo = m->method_data(); - if (mdo != NULL) { - ProfileData *pd = mdo->bci_to_data(branch_bci); - if (pd == NULL) { - tty->print_cr("back branch count = N/A (missing ProfileData)"); - } else { - tty->print_cr("back branch count = %d", pd->as_JumpData()->taken()); - } - } - } - } - } -} - -void SimpleCompPolicy::trace_osr_request(const methodHandle& method, nmethod* osr, int bci) { - if (TraceOnStackReplacement) { - ResourceMark rm; - tty->print(osr != NULL ? "Reused OSR entry for " : "Requesting OSR entry for "); - method->print_short_name(tty); - tty->print_cr(" at bci %d", bci); - } -} -#endif // !PRODUCT - -void SimpleCompPolicy::method_invocation_event(const methodHandle& m, JavaThread* thread) { - const int comp_level = CompLevel_highest_tier; - const int hot_count = m->invocation_count(); - reset_counter_for_invocation_event(m); - - if (is_compilation_enabled() && can_be_compiled(m, comp_level)) { - CompiledMethod* nm = m->code(); - if (nm == NULL ) { - CompileBroker::compile_method(m, InvocationEntryBci, comp_level, m, hot_count, CompileTask::Reason_InvocationCount, thread); - } - } -} - -void SimpleCompPolicy::method_back_branch_event(const methodHandle& m, int bci, JavaThread* thread) { - const int comp_level = CompLevel_highest_tier; - const int hot_count = m->backedge_count(); - - if (is_compilation_enabled() && can_be_osr_compiled(m, comp_level)) { - CompileBroker::compile_method(m, bci, comp_level, m, hot_count, CompileTask::Reason_BackedgeCount, thread); - NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, comp_level, true));) - } -}