[PATCH v2] tools/hotplug: allow tuning of xenwatchdogd arguments

[Olaf Hering <olaf@xxxxxxxxx>]

Currently the arguments for xenwatchdogd are hardcoded with 15s
keep-alive interval and 30s timeout.

It is not possible to tweak these values via
/etc/systemd/system/xen-watchdog.service.d/*.conf because ExecStart
can not be replaced. The only option would be a private copy
/etc/systemd/system/xen-watchdog.service, which may get out of sync
with the Xen provided xen-watchdog.service.

Adjust the service file to recognize XENWATCHDOGD_ARGS= in a
private unit configuration file.

Signed-off-by: Olaf Hering <olaf@xxxxxxxxx>
---

v2: fix "test -n" in init.d

 tools/hotplug/Linux/init.d/xen-watchdog.in          | 7 ++++++-
 tools/hotplug/Linux/systemd/xen-watchdog.service.in | 4 +++-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/tools/hotplug/Linux/init.d/xen-watchdog.in 
b/tools/hotplug/Linux/init.d/xen-watchdog.in
index c05f1f6b6a..b36a94bd8e 100644
--- a/tools/hotplug/Linux/init.d/xen-watchdog.in
+++ b/tools/hotplug/Linux/init.d/xen-watchdog.in
@@ -19,6 +19,11 @@
 
 . @XEN_SCRIPT_DIR@/hotplugpath.sh
 
+xencommons_config=@CONFIG_DIR@/@CONFIG_LEAF_DIR@
+
+test -f $xencommons_config/xencommons && . $xencommons_config/xencommons
+
+test -n "$XENWATCHDOGD_ARGS" || XENWATCHDOGD_ARGS='15 30'
 DAEMON=${sbindir}/xenwatchdogd
 base=$(basename $DAEMON)
 
@@ -46,7 +51,7 @@ start() {
        local r
        echo -n $"Starting domain watchdog daemon: "
 
-       $DAEMON 30 15
+       $DAEMON $XENWATCHDOGD_ARGS
        r=$?
        [ "$r" -eq 0 ] && success $"$base startup" || failure $"$base startup"
        echo
diff --git a/tools/hotplug/Linux/systemd/xen-watchdog.service.in 
b/tools/hotplug/Linux/systemd/xen-watchdog.service.in
index 1eecd2a616..637ab7fd7f 100644
--- a/tools/hotplug/Linux/systemd/xen-watchdog.service.in
+++ b/tools/hotplug/Linux/systemd/xen-watchdog.service.in
@@ -6,7 +6,9 @@ ConditionPathExists=/proc/xen/capabilities
 
 [Service]
 Type=forking
-ExecStart=@sbindir@/xenwatchdogd 30 15
+Environment="XENWATCHDOGD_ARGS=30 15"
+EnvironmentFile=-@CONFIG_DIR@/@CONFIG_LEAF_DIR@/xencommons
+ExecStart=@sbindir@/xenwatchdogd $XENWATCHDOGD_ARGS
 KillSignal=USR1
 
 [Install]