all: remove config for arm64 linaro builders

They've been decomissioned for some months now. Our arm64 builders are
on packet.net these days.

Change-Id: Iaede189157e0298812b2971cdd63599f6096d73d
Reviewed-on: https://go-review.googlesource.com/c/build/+/165781
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

cmd/buildlet/stage0/stage0.go

@@ -85,7 +85,7 @@ func main() {
 		}
 	case "linux/arm64":
 		switch env := os.Getenv("GO_BUILDER_ENV"); env {
-		case "host-linux-arm64-packet", "host-linux-arm64-linaro":
+		case "host-linux-arm64-packet":
 			// No special setup.
 		default:
 			panic(fmt.Sprintf("unknown/unspecified $GO_BUILDER_ENV value %q", env))
@@ -171,7 +171,7 @@ Download:
 		cmd.Args = append(cmd.Args, reverseHostTypeArgs("host-linux-s390x")...)
 	case "linux/arm64":
 		switch buildEnv {
-		case "host-linux-arm64-packet", "host-linux-arm64-linaro":
+		case "host-linux-arm64-packet":
 			hostname := os.Getenv("HOSTNAME") // if empty, docker container name is used
 			cmd.Args = append(cmd.Args,
 				"--reverse-type="+buildEnv,

dashboard/builders.go

@@ -402,15 +402,6 @@ var Hosts = map[string]*HostConfig{
 		SSHUsername:     "debian",
 		HermeticReverse: false, // TODO: use rundockerbuildlet like arm64
 	},
-	"host-linux-arm64-linaro": &HostConfig{
-		Notes:           "Ubuntu xenial; run by Go team, from linaro",
-		IsReverse:       true,
-		HermeticReverse: true,
-		ExpectNum:       5,
-		env:             []string{"GOROOT_BOOTSTRAP=/usr/local/go-bootstrap"},
-		ReverseAliases:  []string{"linux-arm64-buildlet"},
-		SSHUsername:     "root",
-	},
 	"host-linux-arm64-packet": &HostConfig{
 		Notes:           "On 96 core packet.net host (Xenial) in Docker containers (Jessie); run by Go team. See x/build/env/linux-arm64/packet",
 		IsReverse:       true,
@@ -1875,15 +1866,10 @@ func init() {
 		HostType: "host-linux-ppc64le-power9-osu",
 		FlakyNet: true,
 	})
-	addBuilder(BuildConfig{
-		Name:     "linux-arm64-buildlet",
-		HostType: "host-linux-arm64-linaro",
-		FlakyNet: true,
-	})
 	addBuilder(BuildConfig{
 		Name:     "linux-arm64-packet",
 		HostType: "host-linux-arm64-packet",
-		FlakyNet: true, // unknown; just copied from the linaro one
+		FlakyNet: true, // maybe not flaky, but here conservatively
 	})
 	addBuilder(BuildConfig{
 		Name:         "linux-mips",

env/linux-arm64/linaro/Dockerfile

@@ -1,9 +0,0 @@
-# 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.
-
-FROM golang.org/linux-arm64
-
-ENV GO_BUILDER_ENV host-linux-arm64-linaro
-
-CMD ["/usr/local/bin/stage0"]

env/linux-arm64/linaro/README

@@ -1,46 +0,0 @@
-Machines:
-
-r2-a25:
-
-     $ ssh -i ~/keys/id_ed25519_golang1 linaro@64.28.99.28
-     (key: http://go/golang-ssh-key)
-
-Filing tickets:
-
-    https://servicedesk.linaro.org/servicedesk/customer/user/requests
-    (user/pass: http://go/golang-linaro)
-
-Machine details:
-
-  linaro@r2-a25:~# cat /proc/cpuinfo | grep process | wc -l
-  8
- 
-  linaro@r2-a25:~# free
-                total        used        free      shared  buff/cache   available
-  Mem:       32942028      850048    30117168      619288     1974812    31097620
-  Swap:      32165884           0    32165884
-
-
-  linaro@r2-a25:~# lsb_release  -a
-  No LSB modules are available.
-  Distributor ID:    Ubuntu
-  Description:       Ubuntu 16.04.2 LTS
-  Release:           16.04
-  Codename:          xenial
-
-
-But each machine is setup like:
-
-   $ apt-get install docker.io
-   
-   $ build.sh (with Dockerfile in same directory)
-
-   $ echo "<BUILDER KEY>" > /etc/gobuild.key # or custom path, see rundockerbuildlet.go
-   
-   $ GOARCH=arm64 GOOS=linux go install golang.org/x/build/cmd/rundockerbuildlet && \
-     scp -i ~/keys/id_ed25519_golang1 ~/bin/linux_arm64/rundockerbuildlet linaro@64.28.99.28:/usr/local/bin
-
-   $ scp -i ~/keys/id_ed25519_golang1 rundockerbuildlet.service linaro@64.28.99.28:/etc/systemd/user/
-
-   $ systemctl enable /etc/systemd/user/rundockerbuildlet.service
-   $ systemctl start rundockerbuildlet.service

env/linux-arm64/linaro/build.sh

@@ -1,6 +0,0 @@
-#!/bin/bash
-#
-# This is run on the arm64 host with the Dockerfile in the same directory. 
-# The parent Dockerfile and build.sh (linux-arm64/*) must be in parent directory.
-
-(cd ../ && ./build.sh) && docker build -t gobuilder-arm64-linaro:1 .

env/linux-arm64/linaro/rundockerbuildlet.service

@@ -1,13 +0,0 @@
-[Unit]
-Description=Run Buildlets in Docker
-After=network.target
-
-[Install]
-WantedBy=network-online.target
-
-[Service]
-Type=simple
-ExecStart=/usr/local/bin/rundockerbuildlet -basename=linaro -image=gobuilder-arm64-linaro:1 -n=4
-Restart=always
-RestartSec=2
-StartLimitInterval=0