[ovs-dev] [PATCH 2/2] ovs-ctl.in: Restore flows across force-reload-kmod.

[Gurucharan Shetty]

If we want to upgrade from branch1.9 to master (or potential 1.10)
and restore flows across force-reload-kmod, we need to maintain
the value of ofport.

To do this, we fetch the value of ofport before the upgrade and use
it to populate the column 'ofport_request' after ovsdb is upgraded.
We need to do this before vswitchd is restarted as vswitchd
needs the ofport_request column populated before it starts.

Issue #13556
Signed-off-by: Gurucharan Shetty <gshetty at nicira.com>
---
 utilities/ovs-ctl.in |   36 ++++++++++++++++++++++++------------
 1 file changed, 24 insertions(+), 12 deletions(-)

diff --git a/utilities/ovs-ctl.in b/utilities/ovs-ctl.in
index bce74a6..cd8b3ea 100755
--- a/utilities/ovs-ctl.in
+++ b/utilities/ovs-ctl.in
@@ -267,16 +267,15 @@ internal_interfaces () {
     done
 }
 
-save_flows () {
-   if set X `ovs_vsctl -- --real list-br`; then
-        shift
-        if "$datadir/scripts/ovs-save" save-flows "$@" > "$script_flows"; then
-            chmod +x "$script_flows"
-            return 0
-        fi
+ovs_save () {
+    bridges=`ovs_vsctl -- --real list-br`
+    if [ -n "${bridges}" ] && \
+        "$datadir/scripts/ovs-save" "$1" ${bridges} > "$2"; then
+        chmod +x "$2"
+        return 0
     fi
-    script_flows=
-    return 1
+    eval $3=""
+    [ -z "${bridges}" ] && return 0
 }
 
 save_interfaces () {
@@ -284,6 +283,11 @@ save_interfaces () {
         > "${script_interfaces}"
 }
 
+restore_ofports () {
+    [ -n "${script_ofports}" ] && \
+        action "Restoring ofport values" "${script_ofports}"
+}
+
 restore_flows () {
     [ -n "${script_flows}" ] && \
         action "Restoring saved flows" "${script_flows}"
@@ -295,15 +299,22 @@ force_reload_kmod () {
 
     script_interfaces=`mktemp`
     script_flows=`mktemp`
-    trap 'rm -f "${script_interfaces}" "${script_flows}" ' 0
+    script_ofports=`mktemp`
+    trap 'rm -f "${script_interfaces}" "${script_flows}" "${script_ofports}"' 0
 
-    action "Saving flows" save_flows
+    action "Saving flows" ovs_save save-flows "${script_flows}" script_flows
+
+    action "Saving ofport values" ovs_save save-ofports "${script_ofports}" \
+        script_ofports
 
     # Restart the database first, since a large database may take a
     # while to load, and we want to minimize forwarding disruption.
     stop_ovsdb
     start_ovsdb
 
+    # Restore of ofports should happen before vswitchd is restarted.
+    restore_ofports
+
     stop_forwarding
 
     if action "Saving interface configuration" save_interfaces; then
@@ -353,7 +364,8 @@ restart () {
         script_flows=`mktemp`
         trap 'rm -f "${script_flows}"' 0
 
-        action "Saving flows" save_flows
+        action "Saving flows" ovs_save save-flows "${script_flows}" \
+            script_flows
     fi
 
     # Restart the database first, since a large database may take a
-- 
1.7.9.5