1 // Copyright 2018, OpenCensus Authors 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 //go:build go1.11 16 // +build go1.11 17 18 package trace 19 20 import ( 21 "context" 22 t "runtime/trace" 23 ) 24 25 func startExecutionTracerTask(ctx context.Context, name string) (context.Context, func()) { 26 if !t.IsEnabled() { 27 // Avoid additional overhead if 28 // runtime/trace is not enabled. 29 return ctx, func() {} 30 } 31 nctx, task := t.NewTask(ctx, name) 32 return nctx, task.End 33 } 34