start-container-docker.sh: Invoke ssh with "-S none"

to avoid race conditions with several builds in parallel.
This is likely causing the random ssh errors we have been facing.

Change-Id: I28f3bdcedd6a41f60adb19975a65bcbde7cef7b8

1 files changed, 11 insertions, 7 deletions

diff --git a/start-container-docker.sh b/start-container-docker.sh
index b61d15b8..ca2c5171 100755
--- a/start-container-docker.sh
+++ b/start-container-docker.sh
@@ -210,7 +210,11 @@ fi
 
 image=linaro/ci-${container_arch}-tcwg-${task}-ubuntu:${distro}
 
-DOCKER="ssh -v $session_host docker"
+# Avoid connexion sharing because of race conditions with parallel
+# builds
+SSH="ssh -S none"
+
+DOCKER="$SSH -v $session_host docker"
 $DOCKER pull $image || ssh_error $?
 
 SECURITY="--cap-add=SYS_PTRACE"
@@ -224,7 +228,7 @@ SECURITY="--cap-add=SYS_PTRACE"
 SECURITY="${SECURITY} --security-opt seccomp:unconfined"
 
 # Reserve resources according to weight and task
-nproc=$(ssh -v $session_host nproc --all)
+nproc=$($SSH -v $session_host nproc --all)
 memory=$(print_memory_limit "$task" "$weight" "$nproc")
 pids=$(print_pids_limit "$task" "$weight")
 cpus=$(print_cpu_shares "$task" "$weight")
@@ -241,7 +245,7 @@ for bind_mount in "${bind_mounts[@]}"; do
     # If a host bind-mount dir doesn't exist, then docker creates it on
     # the host with root:root owner, which can't be removed by cleanup job.
     dir="${bind_mount%%:*}"
-    ssh -v $session_host mkdir -p "$dir"
+    $SSH -v $session_host mkdir -p "$dir"
 
     docker_dir=$(print_docker_path "$dir")
     bind_mounts_opt=("${bind_mounts_opt[@]}" "-v" "$docker_dir:$bind_mount")
@@ -270,8 +274,8 @@ session_id=$("${docker_run[@]}") || ret=$?
 
 if [ $ret -ne 0 ]; then
     if [ $ret -eq 255 ]; then
-	echo "WARNING: ssh $session_host returned an error ($ret). Trying another ssh connexion to get debug logs"
-	ssh -v $session_host true
+	echo "WARNING: $SSH $session_host returned an error ($ret). Trying another ssh connexion to get debug logs"
+	$SSH -v $session_host true
     else
 	echo "WARNING: docker run returned an error: $ret, trying to continue nonetheless..."
     fi
@@ -318,7 +322,7 @@ exec 1>&3 2>&4
 
 cat <<EOF
 # v1 interface
-CONTAINER="${dryruncmd} ssh -p ${session_port} ${user}${session_host}"
+CONTAINER="${dryruncmd} $SSH -p ${session_port} ${user}${session_host}"
 CONTAINER_CLEANUP="${CONTAINER_CLEANUP}"
 session_host=${session_host}
 session_port=${session_port}
@@ -328,7 +332,7 @@ session_port=${session_port}
 # Source jenkins-helpers.sh for remote_exec
 . "$(dirname "$(readlink -f "$0")")/jenkins-helpers.sh"
 
-${prefix}CONTAINER_RSH="${dryruncmd} ssh -p ${session_port} ${user}${session_host}"
+${prefix}CONTAINER_RSH="${dryruncmd} $SSH -p ${session_port} ${user}${session_host}"
 ${prefix}container_cleanup ()
 {
   [ -f /sys/fs/cgroup/memory/memory.failcnt ] && echo "Number of memory usage failures:" && cat /sys/fs/cgroup/memory/memory.failcnt