runtime/trace: convert tracing.enabled to atomic type

Updates #53821

Change-Id: I8a063ae94568cd2ea65c2e891618069a96139891
Reviewed-on: https://go-review.googlesource.com/c/go/+/423884
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>

diff --git a/src/runtime/trace/annotation.go b/src/runtime/trace/annotation.go
index 9171633b07e52649085c1dc706bfd80bbc0b659c..d47cb8573c61f5f869fd94c5401462eecacabc0c 100644 (file)
--- a/src/runtime/trace/annotation.go
+++ b/src/runtime/trace/annotation.go
@@ -178,8 +178,7 @@ func (r *Region) End() {
 // The information is advisory only. The tracing status
 // may have changed by the time this function returns.
 func IsEnabled() bool {
-       enabled := atomic.LoadInt32(&tracing.enabled)
-       return enabled == 1
+       return tracing.enabled.Load()
 }
 
 //

diff --git a/src/runtime/trace/trace.go b/src/runtime/trace/trace.go
index cf2b6440b2d294a33836b18797abf0a53bac2025..86c97e2a11d8e9e8e435f2ea7f277fcd31abef38 100644 (file)
--- a/src/runtime/trace/trace.go
+++ b/src/runtime/trace/trace.go
@@ -134,7 +134,7 @@ func Start(w io.Writer) error {
                        w.Write(data)
                }
        }()
-       atomic.StoreInt32(&tracing.enabled, 1)
+       tracing.enabled.Store(true)
        return nil
 }
 
@@ -143,12 +143,12 @@ func Start(w io.Writer) error {
 func Stop() {
        tracing.Lock()
        defer tracing.Unlock()
-       atomic.StoreInt32(&tracing.enabled, 0)
+       tracing.enabled.Store(false)
 
        runtime.StopTrace()
 }
 
 var tracing struct {
-       sync.Mutex       // gate mutators (Start, Stop)
-       enabled    int32 // accessed via atomic
+       sync.Mutex // gate mutators (Start, Stop)
+       enabled    atomic.Bool
 }