From c6bf1a210b98474e564b7a9534d5be58d6e05814 Mon Sep 17 00:00:00 2001
From: Mikhail Faraponov <11322032+moredure@users.noreply.github.com>
Date: Mon, 11 Apr 2022 13:39:12 +0300
Subject: [PATCH] crypto/tls: avoid creating handshake context on each write

---
 src/crypto/tls/conn.go | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/src/crypto/tls/conn.go b/src/crypto/tls/conn.go
index fba36d30100736..8375052708ce69 100644
--- a/src/crypto/tls/conn.go
+++ b/src/crypto/tls/conn.go
@@ -1403,6 +1403,16 @@ func (c *Conn) HandshakeContext(ctx context.Context) error {
 }
 
 func (c *Conn) handshakeContext(ctx context.Context) (ret error) {
+	c.handshakeMutex.Lock()
+	defer c.handshakeMutex.Unlock()
+
+	if err := c.handshakeErr; err != nil {
+		return err
+	}
+	if c.handshakeComplete() {
+		return nil
+	}
+
 	handshakeCtx, cancel := context.WithCancel(ctx)
 	// Note: defer this before starting the "interrupter" goroutine
 	// so that we can tell the difference between the input being canceled and
@@ -1436,16 +1446,6 @@ func (c *Conn) handshakeContext(ctx context.Context) (ret error) {
 		}()
 	}
 
-	c.handshakeMutex.Lock()
-	defer c.handshakeMutex.Unlock()
-
-	if err := c.handshakeErr; err != nil {
-		return err
-	}
-	if c.handshakeComplete() {
-		return nil
-	}
-
 	c.in.Lock()
 	defer c.in.Unlock()