From 808c7b67b3ad3c85b7241bd96134b4844fb2b502 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Mon, 16 Mar 2026 07:35:19 -1000
Subject: [PATCH] [core] Inline WarnIfComponentBlockingGuard::finish() into
 header (#14798)

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 esphome/core/component.cpp | 13 ++++---------
 esphome/core/component.h   | 23 +++++++++++++++++++----
 2 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/esphome/core/component.cpp b/esphome/core/component.cpp
index 761f1bd4858..bfe9beb2723 100644
--- a/esphome/core/component.cpp
+++ b/esphome/core/component.cpp
@@ -510,7 +510,8 @@ void PollingComponent::stop_poller() {
 uint32_t PollingComponent::get_update_interval() const { return this->update_interval_; }
 void PollingComponent::set_update_interval(uint32_t update_interval) { this->update_interval_ = update_interval; }
 
-static void __attribute__((noinline, cold)) warn_blocking(Component *component, uint32_t blocking_time) {
+void __attribute__((noinline, cold))
+WarnIfComponentBlockingGuard::warn_blocking(Component *component, uint32_t blocking_time) {
   bool should_warn;
   if (component != nullptr) {
     should_warn = component->should_warn_of_blocking(blocking_time);
@@ -524,10 +525,8 @@ static void __attribute__((noinline, cold)) warn_blocking(Component *component,
   }
 }
 
-uint32_t WarnIfComponentBlockingGuard::finish() {
-  uint32_t curr_time = millis();
-  uint32_t blocking_time = curr_time - this->started_;
 #ifdef USE_RUNTIME_STATS
+void WarnIfComponentBlockingGuard::record_runtime_stats_() {
   // Use micros() for accurate sub-millisecond timing. millis() has insufficient
   // resolution — most components complete in microseconds but millis() only has
   // 1ms granularity, so results were essentially random noise.
@@ -535,12 +534,8 @@ uint32_t WarnIfComponentBlockingGuard::finish() {
     uint32_t duration_us = micros() - this->started_us_;
     global_runtime_stats->record_component_time(this->component_, duration_us);
   }
-#endif
-  if (blocking_time > WARN_IF_BLOCKING_OVER_MS) {
-    warn_blocking(this->component_, blocking_time);
-  }
-  return curr_time;
 }
+#endif
 
 #ifdef USE_SETUP_PRIORITY_OVERRIDE
 void clear_setup_priority_overrides() {
diff --git a/esphome/core/component.h b/esphome/core/component.h
index 1aac1c72191..5fdf23e128a 100644
--- a/esphome/core/component.h
+++ b/esphome/core/component.h
@@ -6,6 +6,7 @@
 #include <string>
 
 #include "esphome/core/defines.h"
+#include "esphome/core/hal.h"
 #include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
 #include "esphome/core/optional.h"
@@ -575,9 +576,7 @@ class PollingComponent : public Component {
   uint32_t update_interval_;
 };
 
-#ifdef USE_RUNTIME_STATS
-uint32_t micros();  // Forward declare for inline constructor
-#endif
+// millis() and micros() are available via hal.h
 
 class WarnIfComponentBlockingGuard {
  public:
@@ -592,7 +591,18 @@ class WarnIfComponentBlockingGuard {
   }
 
   // Finish the timing operation and return the current time
-  uint32_t finish();
+  // Inlined: the fast path is just millis() + subtract + compare
+  inline uint32_t HOT finish() {
+    uint32_t curr_time = millis();
+    uint32_t blocking_time = curr_time - this->started_;
+#ifdef USE_RUNTIME_STATS
+    this->record_runtime_stats_();
+#endif
+    if (blocking_time > WARN_IF_BLOCKING_OVER_MS) [[unlikely]] {
+      warn_blocking(this->component_, blocking_time);
+    }
+    return curr_time;
+  }
 
   ~WarnIfComponentBlockingGuard() = default;
 
@@ -601,7 +611,12 @@ class WarnIfComponentBlockingGuard {
   Component *component_;
 #ifdef USE_RUNTIME_STATS
   uint32_t started_us_;
+  void record_runtime_stats_();
 #endif
+
+ private:
+  // Cold path for blocking warning - defined in component.cpp
+  static void __attribute__((noinline, cold)) warn_blocking(Component *component, uint32_t blocking_time);
 };
 
 // Function to clear setup priority overrides after all components are set up