utilities: Add command to print pipeline oftable starts.

Add "ovn-debug lflow-pipeline-oftable-start-list" to print the starting
OpenFlow table numbers of the ingress and egress logical pipelines.

This lets external consumers that read OpenFlow table statistics safely
compute the actual OpenFlow table of a logical flow (pipeline base +
logical flow table number) during upgrades, avoiding reliance on
lflow-stage-to-ltable, which can be inaccurate when ovn-controller and
ovn-northd run different versions.

Assisted-by: Cursor, with model: claude-4.8-opus-high
Signed-off-by: Aditya Mehakare <aditya.mehakare@nutanix.com>
Acked-by: Naveen Yerramneni <naveen.yerramneni@nutanix.com>
Signed-off-by: Ales Musil <amusil@redhat.com>

Author: aditya-mehakare

NEWS

@@ -95,6 +95,9 @@ Post v26.03.0
      original destination. This enables passive monitoring use cases where
      network functions can observe traffic without being inline in
      the data path.
+   - Added a new "ovn-debug lflow-pipeline-oftable-start-list" command that
+     prints the starting OpenFlow table number of the logical ingress and
+     egress pipelines.
 
 OVN v26.03.0 - xxx xx xxxx
 --------------------------

tests/ovn-util.at

@@ -106,3 +106,10 @@ cookie=$egress, priority=0,metadata=0x1 actions=resubmit(,??)
 OVN_CLEANUP([hv1])
 
 AT_CLEANUP
+
+AT_SETUP([ovn-debug - lflow-pipeline-oftable-start-list])
+AT_CHECK([ovn-debug lflow-pipeline-oftable-start-list], [0], [dnl
+ingress OFTABLE_LOG_INGRESS_PIPELINE
+egress OFTABLE_LOG_EGRESS_PIPELINE
+])
+AT_CLEANUP

utilities/ovn-debug.8.xml

@@ -24,5 +24,10 @@
             Convert the logical flow stage name e.g. <code>ls_in_lb</code> into
             the OpenFlow table number e.g. <code>21</code>.
         </dd>
+        <dt><code>lflow-pipeline-oftable-start-list</code></dt>
+        <dd>
+            Print the starting OpenFlow table number of the
+            <code>ingress</code> and <code>egress</code> pipelines.
+        </dd>
     </dl>
 </manpage>

utilities/ovn-debug.c

@@ -76,6 +76,14 @@ lflow_stage_to_table(struct ovs_cmdl_context *ctx)
     exit(EXIT_SUCCESS);
 }
 
+static void
+lflow_pipeline_oftable_start_list(struct ovs_cmdl_context *ctx OVS_UNUSED)
+{
+    printf("ingress %"PRIu8"\n", (uint8_t) OFTABLE_LOG_INGRESS_PIPELINE);
+    printf("egress %"PRIu8"\n", (uint8_t) OFTABLE_LOG_EGRESS_PIPELINE);
+    exit(EXIT_SUCCESS);
+}
+
 static void
 uuid_to_cookie_str(struct ovs_cmdl_context *ctx)
 {
@@ -102,6 +110,8 @@ lflow-stage-to-ltable STAGE_NAME\n\
   Converts STAGE_NAME into logical flow table number.\n\
 lflow-stage-to-oftable STAGE_NAME\n\
   Converts STAGE_NAME into OpenFlow table number.\n\
+lflow-pipeline-oftable-start-list\n\
+  Prints the starting OpenFlow table number of the logical pipelines.\n\
 uuid-to-cookie UUID\n\
   Converts UUID into cookie format.\n\
 \n\
@@ -161,6 +171,8 @@ main(int argc, char *argv[])
              OVS_RO},
             {"lflow-stage-to-ltable", NULL, 1, 1, lflow_stage_to_table,
              OVS_RO},
+            {"lflow-pipeline-oftable-start-list", NULL, 0, 0,
+             lflow_pipeline_oftable_start_list, OVS_RO},
             {"uuid-to-cookie", NULL, 1, 1, uuid_to_cookie_str,
              OVS_RO},
             { "help", NULL, 0, INT_MAX, help, OVS_RO },