Rename RuntimeProfiler to TieringManager

.. to resolve the overloaded 'runtime' term and overall pick a more
meaningful name for this class. It's neither very related to runtime
(instead it's called periodically when the bytecode interrupt budget is
exhausted); nor is profiling its main purpose.

This class is responsible for controlling tiering decisions, hence the
new name 'TieringManager'.

Bug: v8:7700
Change-Id: Id6f1edf4ebe016d0d81903d0a13e0e1fe6e02142
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3463716Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79101}

BUILD.bazel

@@ -1243,8 +1243,6 @@ filegroup(
         "src/execution/protectors-inl.h",
         "src/execution/protectors.cc",
         "src/execution/protectors.h",
-        "src/execution/runtime-profiler.cc",
-        "src/execution/runtime-profiler.h",
         "src/execution/shared-mutex-guard-if-off-thread.h",
         "src/execution/simulator-base.cc",
         "src/execution/simulator-base.h",
@@ -1255,6 +1253,8 @@ filegroup(
         "src/execution/thread-id.h",
         "src/execution/thread-local-top.cc",
         "src/execution/thread-local-top.h",
+        "src/execution/tiering-manager.cc",
+        "src/execution/tiering-manager.h",
         "src/execution/v8threads.cc",
         "src/execution/v8threads.h",
         "src/execution/vm-state-inl.h",

BUILD.gn

@@ -2921,13 +2921,13 @@ v8_header_set("v8_internal_headers") {
     "src/execution/pointer-authentication.h",
     "src/execution/protectors-inl.h",
     "src/execution/protectors.h",
-    "src/execution/runtime-profiler.h",
     "src/execution/shared-mutex-guard-if-off-thread.h",
     "src/execution/simulator-base.h",
     "src/execution/simulator.h",
     "src/execution/stack-guard.h",
     "src/execution/thread-id.h",
     "src/execution/thread-local-top.h",
+    "src/execution/tiering-manager.h",
     "src/execution/v8threads.h",
     "src/execution/vm-state-inl.h",
     "src/execution/vm-state.h",
@@ -4142,11 +4142,11 @@ v8_source_set("v8_base_without_compiler") {
     "src/execution/messages.cc",
     "src/execution/microtask-queue.cc",
     "src/execution/protectors.cc",
-    "src/execution/runtime-profiler.cc",
     "src/execution/simulator-base.cc",
     "src/execution/stack-guard.cc",
     "src/execution/thread-id.cc",
     "src/execution/thread-local-top.cc",
+    "src/execution/tiering-manager.cc",
     "src/execution/v8threads.cc",
     "src/extensions/cputracemark-extension.cc",
     "src/extensions/externalize-string-extension.cc",

src/api/api.cc

@@ -57,7 +57,6 @@
 #include "src/execution/isolate-inl.h"
 #include "src/execution/messages.h"
 #include "src/execution/microtask-queue.h"
-#include "src/execution/runtime-profiler.h"
 #include "src/execution/simulator.h"
 #include "src/execution/v8threads.h"
 #include "src/execution/vm-state-inl.h"

src/codegen/compiler.cc

@@ -34,7 +34,6 @@
 #include "src/execution/isolate-inl.h"
 #include "src/execution/isolate.h"
 #include "src/execution/local-isolate.h"
-#include "src/execution/runtime-profiler.h"
 #include "src/execution/vm-state-inl.h"
 #include "src/handles/handles.h"
 #include "src/handles/maybe-handles.h"

src/execution/isolate.cc

@@ -53,8 +53,8 @@
 #include "src/execution/messages.h"
 #include "src/execution/microtask-queue.h"
 #include "src/execution/protectors-inl.h"
-#include "src/execution/runtime-profiler.h"
 #include "src/execution/simulator.h"
+#include "src/execution/tiering-manager.h"
 #include "src/execution/v8threads.h"
 #include "src/execution/vm-state-inl.h"
 #include "src/handles/global-handles-inl.h"
@@ -3387,9 +3387,9 @@ void Isolate::Deinit() {
   builtins_.TearDown();
   bootstrapper_->TearDown();
 
-  if (runtime_profiler_ != nullptr) {
-    delete runtime_profiler_;
-    runtime_profiler_ = nullptr;
+  if (tiering_manager_ != nullptr) {
+    delete tiering_manager_;
+    tiering_manager_ = nullptr;
   }
 
   delete heap_profiler_;
@@ -4035,9 +4035,9 @@ bool Isolate::Init(SnapshotData* startup_snapshot_data,
     optimizing_compile_dispatcher_ = new OptimizingCompileDispatcher(this);
   }
 
-  // Initialize runtime profiler before deserialization, because collections may
-  // occur, clearing/updating ICs.
-  runtime_profiler_ = new RuntimeProfiler(this);
+  // Initialize before deserialization since collections may occur,
+  // clearing/updating ICs (and thus affecting tiering decisions).
+  tiering_manager_ = new TieringManager(this);
 
   // If we are deserializing, read the state into the now-empty heap.
   {

src/execution/isolate.h

@@ -121,7 +121,7 @@ class PersistentHandlesList;
 class ReadOnlyArtifacts;
 class RegExpStack;
 class RootVisitor;
-class RuntimeProfiler;
+class TieringManager;
 class SetupIsolateDelegate;
 class Simulator;
 class SnapshotData;
@@ -1095,7 +1095,7 @@ class V8_EXPORT_PRIVATE Isolate final : private HiddenFactory {
   const std::shared_ptr<metrics::Recorder>& metrics_recorder() {
     return metrics_recorder_;
   }
-  RuntimeProfiler* runtime_profiler() { return runtime_profiler_; }
+  TieringManager* tiering_manager() { return tiering_manager_; }
   CompilationCache* compilation_cache() { return compilation_cache_; }
   Logger* logger() {
     // Call InitializeLoggingAndCounters() if logging is needed before
@@ -2071,7 +2071,7 @@ class V8_EXPORT_PRIVATE Isolate final : private HiddenFactory {
   StringStream* incomplete_message_ = nullptr;
   Address isolate_addresses_[kIsolateAddressCount + 1] = {};
   Bootstrapper* bootstrapper_ = nullptr;
-  RuntimeProfiler* runtime_profiler_ = nullptr;
+  TieringManager* tiering_manager_ = nullptr;
   CompilationCache* compilation_cache_ = nullptr;
   std::shared_ptr<Counters> async_counters_;
   base::RecursiveMutex break_access_;

src/execution/stack-guard.cc

@@ -8,7 +8,6 @@
 #include "src/compiler-dispatcher/optimizing-compile-dispatcher.h"
 #include "src/execution/interrupts-scope.h"
 #include "src/execution/isolate.h"
-#include "src/execution/runtime-profiler.h"
 #include "src/execution/simulator.h"
 #include "src/logging/counters.h"
 #include "src/objects/backing-store.h"

src/execution/runtime-profiler.cc → src/execution/tiering-manager.cc

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "src/execution/runtime-profiler.h"
+#include "src/execution/tiering-manager.h"
 
 #include "src/base/platform/platform.h"
 #include "src/codegen/assembler.h"
@@ -22,7 +22,6 @@ namespace internal {
 
 // Maximum size in bytes of generate code for a function to allow OSR.
 static const int kOSRBytecodeSizeAllowanceBase = 119;
-
 static const int kOSRBytecodeSizeAllowancePerTick = 44;
 
 #define OPTIMIZATION_REASON_LIST(V)   \
@@ -85,18 +84,15 @@ void TraceRecompile(JSFunction function, OptimizationReason reason,
 
 }  // namespace
 
-RuntimeProfiler::RuntimeProfiler(Isolate* isolate)
-    : isolate_(isolate), any_ic_changed_(false) {}
-
-void RuntimeProfiler::Optimize(JSFunction function, OptimizationReason reason,
-                               CodeKind code_kind) {
+void TieringManager::Optimize(JSFunction function, OptimizationReason reason,
+                              CodeKind code_kind) {
   DCHECK_NE(reason, OptimizationReason::kDoNotOptimize);
   TraceRecompile(function, reason, code_kind, isolate_);
   function.MarkForOptimization(ConcurrencyMode::kConcurrent);
 }
 
-void RuntimeProfiler::AttemptOnStackReplacement(UnoptimizedFrame* frame,
-                                                int loop_nesting_levels) {
+void TieringManager::AttemptOnStackReplacement(UnoptimizedFrame* frame,
+                                               int loop_nesting_levels) {
   JSFunction function = frame->function();
   SharedFunctionInfo shared = function.shared();
   if (!FLAG_use_osr || !shared.IsUserJavaScript()) {
@@ -122,9 +118,9 @@ void RuntimeProfiler::AttemptOnStackReplacement(UnoptimizedFrame* frame,
       {level + loop_nesting_levels, AbstractCode::kMaxLoopNestingMarker}));
 }
 
-void RuntimeProfiler::MaybeOptimizeFrame(JSFunction function,
-                                         JavaScriptFrame* frame,
-                                         CodeKind code_kind) {
+void TieringManager::MaybeOptimizeFrame(JSFunction function,
+                                        JavaScriptFrame* frame,
+                                        CodeKind code_kind) {
   if (function.IsInOptimizationQueue()) {
     TraceInOptimizationQueue(function);
     return;
@@ -158,7 +154,7 @@ void RuntimeProfiler::MaybeOptimizeFrame(JSFunction function,
   }
 }
 
-bool RuntimeProfiler::MaybeOSR(JSFunction function, UnoptimizedFrame* frame) {
+bool TieringManager::MaybeOSR(JSFunction function, UnoptimizedFrame* frame) {
   int ticks = function.feedback_vector().profiler_ticks();
   if (function.IsMarkedForOptimization() ||
       function.IsMarkedForConcurrentOptimization() ||
@@ -182,9 +178,9 @@ bool ShouldOptimizeAsSmallFunction(int bytecode_size, bool any_ic_changed) {
 
 }  // namespace
 
-OptimizationReason RuntimeProfiler::ShouldOptimize(JSFunction function,
-                                                   BytecodeArray bytecode,
-                                                   JavaScriptFrame* frame) {
+OptimizationReason TieringManager::ShouldOptimize(JSFunction function,
+                                                  BytecodeArray bytecode,
+                                                  JavaScriptFrame* frame) {
   if (function.ActiveTierIsTurbofan()) {
     return OptimizationReason::kDoNotOptimize;
   }
@@ -238,21 +234,22 @@ OptimizationReason RuntimeProfiler::ShouldOptimize(JSFunction function,
   return OptimizationReason::kDoNotOptimize;
 }
 
-RuntimeProfiler::MarkCandidatesForOptimizationScope::
-    MarkCandidatesForOptimizationScope(RuntimeProfiler* profiler)
+TieringManager::OnInterruptTickScope::OnInterruptTickScope(
+    TieringManager* profiler)
     : handle_scope_(profiler->isolate_), profiler_(profiler) {
   TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
                "V8.MarkCandidatesForOptimization");
 }
 
-RuntimeProfiler::MarkCandidatesForOptimizationScope::
-    ~MarkCandidatesForOptimizationScope() {
+TieringManager::OnInterruptTickScope::~OnInterruptTickScope() {
   profiler_->any_ic_changed_ = false;
 }
 
-void RuntimeProfiler::MarkCandidatesForOptimization(JavaScriptFrame* frame) {
+void TieringManager::OnInterruptTick(JavaScriptFrame* frame) {
+  isolate_->counters()->runtime_profiler_ticks()->Increment();
+
   if (!isolate_->use_optimizer()) return;
-  MarkCandidatesForOptimizationScope scope(this);
+  OnInterruptTickScope scope(this);
 
   JSFunction function = frame->function();
   CodeKind code_kind = function.GetActiveTier().value();
@@ -268,16 +265,16 @@ void RuntimeProfiler::MarkCandidatesForOptimization(JavaScriptFrame* frame) {
   MaybeOptimizeFrame(function, frame, code_kind);
 }
 
-void RuntimeProfiler::MarkCandidatesForOptimizationFromBytecode() {
+void TieringManager::OnInterruptTickFromBytecode() {
   JavaScriptFrameIterator it(isolate_);
   DCHECK(it.frame()->is_unoptimized());
-  MarkCandidatesForOptimization(it.frame());
+  OnInterruptTick(it.frame());
 }
 
-void RuntimeProfiler::MarkCandidatesForOptimizationFromCode() {
+void TieringManager::OnInterruptTickFromCode() {
   JavaScriptFrameIterator it(isolate_);
   DCHECK(it.frame()->is_optimized());
-  MarkCandidatesForOptimization(it.frame());
+  OnInterruptTick(it.frame());
 }
 
 }  // namespace internal

src/execution/runtime-profiler.h → src/execution/tiering-manager.h

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef V8_EXECUTION_RUNTIME_PROFILER_H_
-#define V8_EXECUTION_RUNTIME_PROFILER_H_
+#ifndef V8_EXECUTION_TIERING_MANAGER_H_
+#define V8_EXECUTION_TIERING_MANAGER_H_
 
 #include "src/common/assert-scope.h"
 #include "src/handles/handles.h"
@@ -20,14 +20,12 @@ class JSFunction;
 enum class CodeKind;
 enum class OptimizationReason : uint8_t;
 
-class RuntimeProfiler {
+class TieringManager {
  public:
-  explicit RuntimeProfiler(Isolate* isolate);
+  explicit TieringManager(Isolate* isolate) : isolate_(isolate) {}
 
-  // Called from the interpreter when the bytecode interrupt has been exhausted.
-  void MarkCandidatesForOptimizationFromBytecode();
-  // Likewise, from generated code.
-  void MarkCandidatesForOptimizationFromCode();
+  void OnInterruptTickFromBytecode();
+  void OnInterruptTickFromCode();
 
   void NotifyICChanged() { any_ic_changed_ = true; }
 
@@ -35,8 +33,8 @@ class RuntimeProfiler {
                                  int nesting_levels = 1);
 
  private:
-  // Helper function called from MarkCandidatesForOptimization*
-  void MarkCandidatesForOptimization(JavaScriptFrame* frame);
+  // Helper function called from OnInterruptTick*
+  void OnInterruptTick(JavaScriptFrame* frame);
 
   // Make the decision whether to optimize the given function, and mark it for
   // optimization if the decision was 'yes'.
@@ -53,22 +51,22 @@ class RuntimeProfiler {
                 CodeKind code_kind);
   void Baseline(JSFunction function, OptimizationReason reason);
 
-  class V8_NODISCARD MarkCandidatesForOptimizationScope final {
+  class V8_NODISCARD OnInterruptTickScope final {
    public:
-    explicit MarkCandidatesForOptimizationScope(RuntimeProfiler* profiler);
-    ~MarkCandidatesForOptimizationScope();
+    explicit OnInterruptTickScope(TieringManager* profiler);
+    ~OnInterruptTickScope();
 
    private:
     HandleScope handle_scope_;
-    RuntimeProfiler* const profiler_;
+    TieringManager* const profiler_;
     DisallowGarbageCollection no_gc;
   };
 
-  Isolate* isolate_;
-  bool any_ic_changed_;
+  Isolate* const isolate_;
+  bool any_ic_changed_ = false;
 };
 
 }  // namespace internal
 }  // namespace v8
 
-#endif  // V8_EXECUTION_RUNTIME_PROFILER_H_
+#endif  // V8_EXECUTION_TIERING_MANAGER_H_

src/heap/heap.cc

@@ -30,7 +30,6 @@
 #include "src/execution/embedder-state.h"
 #include "src/execution/isolate-utils-inl.h"
 #include "src/execution/microtask-queue.h"
-#include "src/execution/runtime-profiler.h"
 #include "src/execution/v8threads.h"
 #include "src/execution/vm-state-inl.h"
 #include "src/handles/global-handles-inl.h"

src/ic/ic.cc

@@ -17,7 +17,7 @@
 #include "src/execution/frames-inl.h"
 #include "src/execution/isolate-inl.h"
 #include "src/execution/protectors-inl.h"
-#include "src/execution/runtime-profiler.h"
+#include "src/execution/tiering-manager.h"
 #include "src/handles/handles-inl.h"
 #include "src/ic/call-optimization.h"
 #include "src/ic/handler-configuration-inl.h"
@@ -345,7 +345,7 @@ void IC::OnFeedbackChanged(Isolate* isolate, FeedbackVector vector,
   }
 #endif
 
-  isolate->runtime_profiler()->NotifyICChanged();
+  isolate->tiering_manager()->NotifyICChanged();
 }
 
 namespace {

src/init/v8.cc

@@ -17,7 +17,6 @@
 #include "src/deoptimizer/deoptimizer.h"
 #include "src/execution/frames.h"
 #include "src/execution/isolate.h"
-#include "src/execution/runtime-profiler.h"
 #include "src/execution/simulator.h"
 #include "src/init/bootstrapper.h"
 #include "src/libsampler/sampler.h"

src/logging/log.cc

@@ -21,7 +21,6 @@
 #include "src/deoptimizer/deoptimizer.h"
 #include "src/diagnostics/perf-jit.h"
 #include "src/execution/isolate.h"
-#include "src/execution/runtime-profiler.h"
 #include "src/execution/v8threads.h"
 #include "src/execution/vm-state-inl.h"
 #include "src/handles/global-handles.h"

src/runtime/runtime-internal.cc

@@ -17,7 +17,7 @@
 #include "src/execution/frames-inl.h"
 #include "src/execution/isolate-inl.h"
 #include "src/execution/messages.h"
-#include "src/execution/runtime-profiler.h"
+#include "src/execution/tiering-manager.h"
 #include "src/handles/maybe-handles.h"
 #include "src/init/bootstrapper.h"
 #include "src/logging/counters.h"
@@ -372,8 +372,7 @@ void BytecodeBudgetInterruptFromBytecode(Isolate* isolate,
   }
   if (should_mark_for_optimization) {
     SealHandleScope shs(isolate);
-    isolate->counters()->runtime_profiler_ticks()->Increment();
-    isolate->runtime_profiler()->MarkCandidatesForOptimizationFromBytecode();
+    isolate->tiering_manager()->OnInterruptTickFromBytecode();
   }
 }
 }  // namespace
@@ -427,8 +426,7 @@ RUNTIME_FUNCTION(Runtime_BytecodeBudgetInterruptFromCode) {
   FeedbackVector::SetInterruptBudget(*feedback_cell);
 
   SealHandleScope shs(isolate);
-  isolate->counters()->runtime_profiler_ticks()->Increment();
-  isolate->runtime_profiler()->MarkCandidatesForOptimizationFromCode();
+  isolate->tiering_manager()->OnInterruptTickFromCode();
   return ReadOnlyRoots(isolate).undefined_value();
 }
 

src/runtime/runtime-test.cc

@@ -20,7 +20,7 @@
 #include "src/execution/frames-inl.h"
 #include "src/execution/isolate-inl.h"
 #include "src/execution/protectors-inl.h"
-#include "src/execution/runtime-profiler.h"
+#include "src/execution/tiering-manager.h"
 #include "src/heap/heap-inl.h"  // For ToBoolean. TODO(jkummerow): Drop.
 #include "src/heap/heap-write-barrier-inl.h"
 #include "src/ic/stub-cache.h"
@@ -514,7 +514,7 @@ RUNTIME_FUNCTION(Runtime_OptimizeOsr) {
 
   // Make the profiler arm all back edges in unoptimized code.
   if (it.frame()->is_unoptimized()) {
-    isolate->runtime_profiler()->AttemptOnStackReplacement(
+    isolate->tiering_manager()->AttemptOnStackReplacement(
         UnoptimizedFrame::cast(it.frame()),
         AbstractCode::kMaxLoopNestingMarker);
   }