raft: Save and read new election timer in header snapshot.

This patch store the latest election timer in snapshot during log
compression, and when server restarts it reads the value from the log.
Without this, any previous changes to election timer will be lost
in the log, and if server restarts, it will use the default value
instead of the changed value.

Fixes: commit 8e35461 ("ovsdb raft: Support leader election time change online.")
Signed-off-by: Han Zhou <hzhou8@ebay.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/ovsdb/raft-private.c b/ovsdb/raft-private.c
index 98c68a958..26d39a087 100644
--- a/ovsdb/raft-private.c
+++ b/ovsdb/raft-private.c
@@ -284,6 +284,7 @@ raft_entry_clone(struct raft_entry *dst, const struct raft_entry *src)
     dst->data = json_nullable_clone(src->data);
     dst->eid = src->eid;
     dst->servers = json_nullable_clone(src->servers);
+    dst->election_timer = src->election_timer;
 }
 
 void
@@ -405,6 +406,8 @@ raft_header_from_json__(struct raft_header *h, struct ovsdb_parser *p)
                 ovsdb_parser_member(p, "prev_data", OP_ANY));
             h->snap.eid = raft_parse_required_uuid(p, "prev_eid");
             h->snap.term = raft_parse_required_uint64(p, "prev_term");
+            h->snap.election_timer = raft_parse_optional_uint64(
+                p, "prev_election_timer");
         }
     }
 
@@ -457,6 +460,10 @@ raft_header_to_json(const struct raft_header *h)
         }
         json_object_put_format(json, "prev_eid",
                                UUID_FMT, UUID_ARGS(&h->snap.eid));
+        if (h->snap.election_timer) {
+            raft_put_uint64(json, "prev_election_timer",
+                            h->snap.election_timer);
+        }
     }
 
     return json;