timers: refactor timer list processing

Instead of using kOnTimeout index to track a special list
processing function, just pass in a function to C++ at
startup that executes all handles and determines which
function to call.

This change improves the performance of unpooled timeouts
by roughly 20%, as well as makes the unref/ref processing
easier to follow.

PR-URL: https://github.com/nodejs/node/pull/18582
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Vladimir de Turckheim <vlad2t@hotmail.com>
Reviewed-By: Evan Lucas <evanlucas@me.com>

1 files changed, 9 insertions, 8 deletions

diff --git a/src/timer_wrap.cc b/src/timer_wrap.cc
index 441974ae77b..02c0b816698 100644
--- a/src/timer_wrap.cc
+++ b/src/timer_wrap.cc
@@ -41,8 +41,6 @@ using v8::Object;
 using v8::String;
 using v8::Value;
 
-const uint32_t kOnTimeout = 0;
-
 class TimerWrap : public HandleWrap {
  public:
   static void Initialize(Local<Object> target,
@@ -53,8 +51,6 @@ class TimerWrap : public HandleWrap {
     Local<String> timerString = FIXED_ONE_BYTE_STRING(env->isolate(), "Timer");
     constructor->InstanceTemplate()->SetInternalFieldCount(1);
     constructor->SetClassName(timerString);
-    constructor->Set(FIXED_ONE_BYTE_STRING(env->isolate(), "kOnTimeout"),
-                     Integer::New(env->isolate(), kOnTimeout));
 
     env->SetTemplateMethod(constructor, "now", Now);
 
@@ -71,18 +67,22 @@ class TimerWrap : public HandleWrap {
     target->Set(timerString, constructor->GetFunction());
 
     target->Set(env->context(),
-                FIXED_ONE_BYTE_STRING(env->isolate(), "setImmediateCallback"),
-                env->NewFunctionTemplate(SetImmediateCallback)
+                FIXED_ONE_BYTE_STRING(env->isolate(), "setupTimers"),
+                env->NewFunctionTemplate(SetupTimers)
                    ->GetFunction(env->context()).ToLocalChecked()).FromJust();
   }
 
   size_t self_size() const override { return sizeof(*this); }
 
  private:
-  static void SetImmediateCallback(const FunctionCallbackInfo<Value>& args) {
+  static void SetupTimers(const FunctionCallbackInfo<Value>& args) {
     CHECK(args[0]->IsFunction());
+    CHECK(args[1]->IsFunction());
     auto env = Environment::GetCurrent(args);
+
     env->set_immediate_callback_function(args[0].As<Function>());
+    env->set_timers_callback_function(args[1].As<Function>());
+
     auto toggle_ref_cb = [] (const FunctionCallbackInfo<Value>& args) {
       Environment::GetCurrent(args)->ToggleImmediateRef(args[0]->IsTrue());
     };
@@ -142,7 +142,8 @@ class TimerWrap : public HandleWrap {
     Local<Value> args[1];
     do {
       args[0] = env->GetNow();
-      ret = wrap->MakeCallback(kOnTimeout, 1, args).ToLocalChecked();
+      ret = wrap->MakeCallback(env->timers_callback_function(), 1, args)
+                .ToLocalChecked();
     } while (ret->IsUndefined() &&
              !env->tick_info()->has_thrown() &&
              wrap->object()->Get(env->context(),