Visiting goroutine stacks by pprof can block all goroutines

[lixiaojun629]

What version of Go are you using (go version)?

$ go version
go version go1.13.4 darwin/amd64

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/rilke/Library/Caches/go-build"
GOENV="/Users/rilke/Library/Application Support/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GONOPROXY=""
GONOSUMDB=""
GOOS="darwin"
GOPATH="/Users/rilke/go"
GOPRIVATE=""
GOPROXY="https://goproxy.io,direct"
GOROOT="/usr/local/Cellar/go/1.13.4/libexec"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/Cellar/go/1.13.4/libexec/pkg/tool/darwin_amd64"
GCCGO="gccgo"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/jg/d03tz52x12g_xf_x7cmdtn840000gn/T/go-build179904585=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

I run the code below, and open the url http://localhost:6060/debug/pprof/goroutine?debug=1 in my browser. But the page never show and the string "xx" stop printing, which means goroutine2 stop running.

package main

import (
	"fmt"
	"net/http"
	_ "net/http/pprof"
)

func main() {
        //goroutine1
	go func() {
		for {
		}
	}()
       //goroutine2
	go func() {
		for {
			fmt.Println("xx")
		}
	}()

	http.ListenAndServe("0.0.0.0:6060", nil)
}

What did you expect to see?

I expect the page http://localhost:6060/debug/pprof/goroutine?debug=1 to be loaded normally, and goroutine2 should not stop printing

What did you see instead?

The page http://localhost:6060/debug/pprof/goroutine?debug=1 never load and goroutine2 stop printing when I visit the url http://localhost:6060/debug/pprof/goroutine?debug=1 in my browser.

[hyangah]

Seems like #10958 - for goroutine profile, runtime tries to stop the world.

[ianlancetaylor]

Don't write busy loops in Go.

That said, this should work better in the upcoming Go 1.14 release. Closing as dup of #10958.