From e3915210aa7dfaff49af07821e65b214c80de229 Mon Sep 17 00:00:00 2001
From: yusing <yusing.wys@gmail.com>
Date: Sat, 1 Nov 2025 02:18:24 +0800
Subject: [PATCH] fix(time): data race in DefaultTimeNow

---
 internal/utils/time_now.go      | 12 +++++++-----
 internal/utils/time_now_test.go |  6 ++++--
 2 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/internal/utils/time_now.go b/internal/utils/time_now.go
index 2426f8ff..d33aa91d 100644
--- a/internal/utils/time_now.go
+++ b/internal/utils/time_now.go
@@ -10,7 +10,7 @@ var (
 	TimeNow           = DefaultTimeNow
 	shouldCallTimeNow atomic.Bool
 	timeNowTicker     = time.NewTicker(shouldCallTimeNowInterval)
-	lastTimeNow       = time.Now()
+	lastTimeNow       = atomic.NewTime(time.Now())
 )
 
 const shouldCallTimeNowInterval = 100 * time.Millisecond
@@ -26,11 +26,13 @@ func MockTimeNow(t time.Time) {
 //
 // Returned value may have +-100ms error.
 func DefaultTimeNow() time.Time {
-	if shouldCallTimeNow.Load() {
-		lastTimeNow = time.Now()
-		shouldCallTimeNow.Store(false)
+	swapped := shouldCallTimeNow.CompareAndSwap(false, true)
+	if swapped { // first call
+		now := time.Now()
+		lastTimeNow.Store(now)
+		return now
 	}
-	return lastTimeNow
+	return lastTimeNow.Load()
 }
 
 func init() {
diff --git a/internal/utils/time_now_test.go b/internal/utils/time_now_test.go
index f2ddf549..3607c16f 100644
--- a/internal/utils/time_now_test.go
+++ b/internal/utils/time_now_test.go
@@ -5,16 +5,18 @@ import (
 	"time"
 )
 
+var sink time.Time
+
 func BenchmarkTimeNow(b *testing.B) {
 	b.Run("default", func(b *testing.B) {
 		for b.Loop() {
-			time.Now()
+			sink = time.Now()
 		}
 	})
 
 	b.Run("reduced_call", func(b *testing.B) {
 		for b.Loop() {
-			DefaultTimeNow()
+			sink = DefaultTimeNow()
 		}
 	})
 }