From 5c4fcaa5c17baf8e768fb6840dbd0626f20656ba Mon Sep 17 00:00:00 2001
From: Ziheng Liu <lzhfromustc@gmail.com>
Date: Sat, 3 Aug 2019 22:01:51 -0700
Subject: [PATCH] Change Unlock to defer Unlock, to avoid data race

---
 internal/transport/flowcontrol.go | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/internal/transport/flowcontrol.go b/internal/transport/flowcontrol.go
index 5ea997a7e45b..f262edd8ecda 100644
--- a/internal/transport/flowcontrol.go
+++ b/internal/transport/flowcontrol.go
@@ -149,6 +149,7 @@ func (f *inFlow) maybeAdjust(n uint32) uint32 {
 		n = uint32(math.MaxInt32)
 	}
 	f.mu.Lock()
+	defer f.mu.Unlock()
 	// estSenderQuota is the receiver's view of the maximum number of bytes the sender
 	// can send without a window update.
 	estSenderQuota := int32(f.limit - (f.pendingData + f.pendingUpdate))
@@ -169,10 +170,8 @@ func (f *inFlow) maybeAdjust(n uint32) uint32 {
 			// is padded; We will fallback on the current available window(at least a 1/4th of the limit).
 			f.delta = n
 		}
-		f.mu.Unlock()
 		return f.delta
 	}
-	f.mu.Unlock()
 	return 0
 }