dashboard: add 32-bit gccgo builder; improve performance of gccgo builds on docker

This change adds a 32-bit builder for gccgo and fixes some specific
configuration problems with the docker image/coordinator to speed up builds.
The go builder running on the linux-x86-gccgo image has been modified to run
`make -j16` when building to reduce build times from ~60 minutes to ~10 minutes
and the coordinator has been modified to run the command `make check-go -j16`
to reduce testsuite run times from ~30 minutes to ~10 minutes.

LGTM=bradfitz
R=bradfitz
CC=adg, golang-codereviews
https://golang.org/cl/151530043

dashboard/coordinator/main.go

@@ -62,7 +62,6 @@ type buildConfig struct {
 	name    string   // "linux-amd64-race"
 	image   string   // Docker image to use to build
 	cmd     string   // optional -cmd flag (relative to go/src/)
-	cmdTimeout time.Duration // time to wait for optional cmd to finish
 	env     []string // extra environment ("key=value") pairs
 	dashURL string   // url of the build dashboard
 	tool    string   // the tool this configuration is for
@@ -81,8 +80,14 @@ func main() {
 	addBuilder(buildConfig{
 		name:    "linux-amd64-gccgo",
 		image:   "gobuilders/linux-x86-gccgo",
-		cmd:        "make check-go -kj",
+		cmd:     "make RUNTESTFLAGS=\"--target_board=unix/-m64\" check-go -j16",
-		cmdTimeout: 60 * time.Minute,
+		dashURL: "https://build.golang.org/gccgo",
+		tool:    "gccgo",
+	})
+	addBuilder(buildConfig{
+		name:    "linux-386-gccgo",
+		image:   "gobuilders/linux-x86-gccgo",
+		cmd:     "make RUNTESTFLAGS=\"--target_board=unix/-m32\" check-go -j16",
 		dashURL: "https://build.golang.org/gccgo",
 		tool:    "gccgo",
 	})
@@ -286,7 +291,6 @@ func (conf buildConfig) dockerRunArgs(rev string) (args []string) {
 	)
 	if conf.cmd != "" {
 		args = append(args, "-cmd", conf.cmd)
-		args = append(args, "-cmdTimeout", conf.cmdTimeout.String())
 	}
 	args = append(args, conf.name)
 	return
@@ -302,9 +306,6 @@ func addBuilder(c buildConfig) {
 	if _, dup := builders[c.name]; dup {
 		panic("dup name")
 	}
-	if c.cmdTimeout == 0 {
-		c.cmdTimeout = 10 * time.Minute
-	}
 	if c.dashURL == "" {
 		c.dashURL = "https://build.golang.org"
 	}

dashboard/env/linux-x86-gccgo/Dockerfile

@@ -2,9 +2,9 @@
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file.
 
-# gobuilders/linux-x86-gccgo for 64-bit gccgo.
+# gobuilders/linux-x86-gccgo for 32- and 64-bit gccgo.
 
-FROM gobuilders/linux-x86-base
+FROM debian:wheezy
 MAINTAINER golang-dev <golang-dev@googlegroups.com>
 
 ENV DEBIAN_FRONTEND noninteractive
@@ -14,3 +14,6 @@ RUN /scripts/install-apt-deps.sh
 
 ADD /scripts/install-gold.sh /scripts/
 RUN /scripts/install-gold.sh
+
+ADD /scripts/install-gccgo-builder.sh /scripts/
+RUN /scripts/install-gccgo-builder.sh && test -f /usr/local/bin/builder

dashboard/env/linux-x86-gccgo/Makefile

@@ -5,8 +5,11 @@
 docker: Dockerfile
 	docker build -t gobuilders/linux-x86-gccgo .
 
-upload: docker
+docker-linux.gccgo.tar.gz: docker
 	docker save gobuilders/linux-x86-gccgo | gzip | (cd ../../coordinator/buildongce && go run create.go --write_object=go-builder-data/docker-linux.gccgo.tar.gz)
 
 check: docker
-	docker run gobuilders/linux-x86-gccgo /usr/local/bin/builder -tool="gccgo" -rev=b9151e911a54 -buildroot=/gccgo -v -cmd='make check-go -kj' -report=false linux-amd64-gccgo-temp
+	docker run gobuilders/linux-x86-gccgo /usr/local/bin/builder -tool="gccgo" -rev=b9151e911a54 -v -cmd='make RUNTESTFLAGS="--target_board=unix/-m64" check-go' -report=false linux-amd64-gccgo-temp
+
+check32: docker
+	docker run gobuilders/linux-x86-gccgo /usr/local/bin/builder -tool="gccgo" -rev=b9151e911a54 -v -cmd='make RUNTESTFLAGS="--target_board=unix/-m32" check-go' -report=false linux-386-gccgo-temp

dashboard/env/linux-x86-gccgo/scripts/install-apt-deps.sh

@@ -1,12 +1,20 @@
 set -ex
 
 apt-get update
+# For running curl to get the gccgo builder binary.
+apt-get install -y --no-install-recommends curl ca-certificates
+# Optionally used by some net/http tests:
+apt-get install -y --no-install-recommends strace
 # For using numeric libraries within GCC.
 apt-get install -y --no-install-recommends libgmp10-dev libmpc-dev libmpfr-dev
 # For building binutils and gcc from source.
 apt-get install -y --no-install-recommends make g++ flex bison
+# Same as above, but for 32-bit builds as well.
+apt-get install -y --no-install-recommends libc6-dev-i386 g++-multilib
 # For running the extended gccgo testsuite
 apt-get install -y --no-install-recommends dejagnu
+# For interacting with the gccgo source and git mirror:
+apt-get install -y --no-install-recommends mercurial git-core
 
 apt-get clean
 rm -rf /var/lib/apt/lists

dashboard/env/linux-x86-gccgo/scripts/install-gccgo-builder.sh

@@ -0,0 +1,7 @@
+set -ex
+
+# Installs a version of the go.tools dashboard builder that runs the gccgo build
+# command assuming there are 16 cores available to speed up build times.
+# TODO(cmang): There should be an option in the builder to specify this.
+
+curl -o /usr/local/bin/builder http://storage.googleapis.com/go-builder-data/gccgo_builder && chmod +x /usr/local/bin/builder