[docker-syncd-vs]: add support for vs syncd docker auto restart (#4344)

Signed-off-by: Guohan Lu <lguohan@gmail.com>

platform/vs/docker-syncd-vs/Dockerfile.j2

@@ -24,6 +24,8 @@ debs/{{ deb }}{{' '}}
 COPY ["start.sh", "/usr/bin/"]
 
 COPY ["supervisord.conf", "/etc/supervisor/conf.d/"]
+COPY ["files/supervisor-proc-exit-listener", "/usr/bin"]
+COPY ["critical_processes", "/etc/supervisor/"]
 
 ## Clean up
 RUN apt-get clean -y; apt-get autoclean -y; apt-get autoremove -y

platform/vs/docker-syncd-vs/critical_processes

@@ -0,0 +1 @@
+syncd

platform/vs/docker-syncd-vs/supervisord.conf

@@ -3,6 +3,12 @@ logfile_maxbytes=1MB
 logfile_backups=2
 nodaemon=true
 
+[eventlistener:supervisor-proc-exit-listener]
+command=/usr/bin/supervisor-proc-exit-listener --container-name syncd
+events=PROCESS_STATE_EXITED
+autostart=true
+autorestart=unexpected
+
 [program:start.sh]
 command=/usr/bin/start.sh
 priority=1
@@ -15,7 +21,7 @@ stderr_logfile=syslog
 command=/usr/sbin/rsyslogd -n
 priority=2
 autostart=false
-autorestart=false
+autorestart=unexpected
 stdout_logfile=syslog
 stderr_logfile=syslog