From 429bae715876c69853bb63db1733f580e293c916 Mon Sep 17 00:00:00 2001 From: Michael Anthony Knyszek Date: Thu, 20 Dec 2018 20:21:45 +0000 Subject: runtime: skip TestLockOSThreadAvoidsStatePropagation if one can't unshare This change splits a testprog out of TestLockOSThreadExit and makes it its own test. Then, this change makes the testprog exit prematurely with a special message if unshare fails with EPERM because not all of the builders allow the user to call the unshare syscall. Also, do some minor cleanup on the TestLockOSThread* tests. Fixes #29366. Change-Id: Id8a9f6c4b16e26af92ed2916b90b0249ba226dbe Reviewed-on: https://go-review.googlesource.com/c/155437 Run-TryBot: Michael Knyszek TryBot-Result: Gobot Gobot Reviewed-by: Brad Fitzpatrick --- src/runtime/testdata/testprog/syscalls_linux.go | 59 +++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 src/runtime/testdata/testprog/syscalls_linux.go (limited to 'src/runtime/testdata/testprog/syscalls_linux.go') diff --git a/src/runtime/testdata/testprog/syscalls_linux.go b/src/runtime/testdata/testprog/syscalls_linux.go new file mode 100644 index 0000000000..b8ac087626 --- /dev/null +++ b/src/runtime/testdata/testprog/syscalls_linux.go @@ -0,0 +1,59 @@ +// 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 main + +import ( + "bytes" + "fmt" + "io/ioutil" + "os" + "syscall" +) + +func gettid() int { + return syscall.Gettid() +} + +func tidExists(tid int) (exists, supported bool) { + stat, err := ioutil.ReadFile(fmt.Sprintf("/proc/self/task/%d/stat", tid)) + if os.IsNotExist(err) { + return false, true + } + // Check if it's a zombie thread. + state := bytes.Fields(stat)[2] + return !(len(state) == 1 && state[0] == 'Z'), true +} + +func getcwd() (string, error) { + if !syscall.ImplementsGetwd { + return "", nil + } + // Use the syscall to get the current working directory. + // This is imperative for checking for OS thread state + // after an unshare since os.Getwd might just check the + // environment, or use some other mechanism. + var buf [4096]byte + n, err := syscall.Getcwd(buf[:]) + if err != nil { + return "", err + } + // Subtract one for null terminator. + return string(buf[:n-1]), nil +} + +func unshareFs() error { + err := syscall.Unshare(syscall.CLONE_FS) + if err != nil { + errno, ok := err.(syscall.Errno) + if ok && errno == syscall.EPERM { + return errNotPermitted + } + } + return err +} + +func chdir(path string) error { + return syscall.Chdir(path) +} -- cgit v1.3-5-g9baa