1 files changed, 52 insertions, 0 deletions
diff --git a/src/runtime/pprof/runtime.go b/src/runtime/pprof/runtime.go
new file mode 100644
index 0000000..8d37c7d
--- /dev/null
+++ b/src/runtime/pprof/runtime.go
@@ -0,0 +1,52 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pprof
+
+import (
+	"context"
+	"runtime"
+	"unsafe"
+)
+
+// runtime_FrameStartLine is defined in runtime/symtab.go.
+//
+//go:noescape
+func runtime_FrameStartLine(f *runtime.Frame) int
+
+// runtime_FrameSymbolName is defined in runtime/symtab.go.
+//
+//go:noescape
+func runtime_FrameSymbolName(f *runtime.Frame) string
+
+// runtime_expandFinalInlineFrame is defined in runtime/symtab.go.
+func runtime_expandFinalInlineFrame(stk []uintptr) []uintptr
+
+// runtime_setProfLabel is defined in runtime/proflabel.go.
+func runtime_setProfLabel(labels unsafe.Pointer)
+
+// runtime_getProfLabel is defined in runtime/proflabel.go.
+func runtime_getProfLabel() unsafe.Pointer
+
+// SetGoroutineLabels sets the current goroutine's labels to match ctx.
+// A new goroutine inherits the labels of the goroutine that created it.
+// This is a lower-level API than [Do], which should be used instead when possible.
+func SetGoroutineLabels(ctx context.Context) {
+	ctxLabels, _ := ctx.Value(labelContextKey{}).(*labelMap)
+	runtime_setProfLabel(unsafe.Pointer(ctxLabels))
+}
+
+// Do calls f with a copy of the parent context with the
+// given labels added to the parent's label map.
+// Goroutines spawned while executing f will inherit the augmented label-set.
+// Each key/value pair in labels is inserted into the label map in the
+// order provided, overriding any previous value for the same key.
+// The augmented label map will be set for the duration of the call to f
+// and restored once f returns.
+func Do(ctx context.Context, labels LabelSet, f func(context.Context)) {
+	defer SetGoroutineLabels(ctx)
+	ctx = WithLabels(ctx, labels)
+	SetGoroutineLabels(ctx)
+	f(ctx)
+}