runtime: convert kqueue netpollWakeSig to atomic type

Updates #53821

Change-Id: I85d7444be36967e1e7e0ff2ce2f19b73581ecdde
Reviewed-on: https://go-review.googlesource.com/c/go/+/423880
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Keith Randall <khr@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/src/runtime/netpoll_kqueue.go b/src/runtime/netpoll_kqueue.go
index 78d1663ad9..5ae77b57f2 100644
--- a/src/runtime/netpoll_kqueue.go
+++ b/src/runtime/netpoll_kqueue.go
@@ -18,7 +18,7 @@ var (
 
 	netpollBreakRd, netpollBreakWr uintptr // for netpollBreak
 
-	netpollWakeSig uint32 // used to avoid duplicate calls of netpollBreak
+	netpollWakeSig atomic.Uint32 // used to avoid duplicate calls of netpollBreak
 )
 
 func netpollinit() {
@@ -84,7 +84,7 @@ func netpollarm(pd *pollDesc, mode int) {
 // netpollBreak interrupts a kevent.
 func netpollBreak() {
 	// Failing to cas indicates there is an in-flight wakeup, so we're done here.
-	if !atomic.Cas(&netpollWakeSig, 0, 1) {
+	if !netpollWakeSig.CompareAndSwap(0, 1) {
 		return
 	}
 
@@ -155,7 +155,7 @@ retry:
 				// if blocking.
 				var tmp [16]byte
 				read(int32(netpollBreakRd), noescape(unsafe.Pointer(&tmp[0])), int32(len(tmp)))
-				atomic.Store(&netpollWakeSig, 0)
+				netpollWakeSig.Store(0)
 			}
 			continue
 		}