From 26d1224862d03d7fae7d63a3b242132343675dfd Mon Sep 17 00:00:00 2001
From: Andy Pan <panjf2000@gmail.com>
Date: Sat, 27 Nov 2021 20:21:45 +0800
Subject: [PATCH] Reduce the maximum times of backoff in spin lock and update
 the tests

---
 internal/spinlock.go      |  2 +-
 internal/spinlock_test.go | 26 +++-----------------------
 2 files changed, 4 insertions(+), 24 deletions(-)

diff --git a/internal/spinlock.go b/internal/spinlock.go
index 5e8572c..6261f74 100644
--- a/internal/spinlock.go
+++ b/internal/spinlock.go
@@ -12,7 +12,7 @@ import (
 
 type spinLock uint32
 
-const maxBackoff = 64
+const maxBackoff = 16
 
 func (sl *spinLock) Lock() {
 	backoff := 1
diff --git a/internal/spinlock_test.go b/internal/spinlock_test.go
index 27d57ab..cabf5e7 100644
--- a/internal/spinlock_test.go
+++ b/internal/spinlock_test.go
@@ -34,30 +34,10 @@ func (sl *originSpinLock) Unlock() {
 	atomic.StoreUint32((*uint32)(sl), 0)
 }
 
-func GetOriginSpinLock() sync.Locker {
+func NewOriginSpinLock() sync.Locker {
 	return new(originSpinLock)
 }
 
-type backOffSpinLock uint32
-
-func (sl *backOffSpinLock) Lock() {
-	wait := 1
-	for !atomic.CompareAndSwapUint32((*uint32)(sl), 0, 1) {
-		for i := 0; i < wait; i++ {
-			runtime.Gosched()
-		}
-		wait <<= 1
-	}
-}
-
-func (sl *backOffSpinLock) Unlock() {
-	atomic.StoreUint32((*uint32)(sl), 0)
-}
-
-func GetBackOffSpinLock() sync.Locker {
-	return new(backOffSpinLock)
-}
-
 func BenchmarkMutex(b *testing.B) {
 	m := sync.Mutex{}
 	b.RunParallel(func(pb *testing.PB) {
@@ -70,7 +50,7 @@ func BenchmarkMutex(b *testing.B) {
 }
 
 func BenchmarkSpinLock(b *testing.B) {
-	spin := GetOriginSpinLock()
+	spin := NewOriginSpinLock()
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
 			spin.Lock()
@@ -81,7 +61,7 @@ func BenchmarkSpinLock(b *testing.B) {
 }
 
 func BenchmarkBackOffSpinLock(b *testing.B) {
-	spin := GetBackOffSpinLock()
+	spin := NewSpinLock()
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
 			spin.Lock()