c/topics: use topic table revision to detect changes in generator

Topic table partition generator is a simple helper to asynchronously iterate over a topic table which may have a lot of elements. The generator validates if `topic_table` changed while the loop yield for the other tasks. The check was incorrect as it was validating the topic table revision which is updated after the snapshot is applied. Fixed the issue by validating it `_topics_map_revision` changed during the scheduling point. Fixes: #core-internal/1259 Signed-off-by: Michał Maślanka <[email protected]> (cherry picked from commit 14726e2)
redpanda-data · Apr 22, 2024 · 557c48b · 557c48b
1 parent d263cba
commit 557c48b
Showing 1 changed file with 2 additions and 3 deletions.
diff --git a/src/v/cluster/topic_table_partition_generator.cc b/src/v/cluster/topic_table_partition_generator.cc
@@ -19,7 +19,7 @@ topic_table_partition_generator_exception::
 topic_table_partition_generator::topic_table_partition_generator(
   ss::sharded<topic_table>& topic_table, size_t batch_size)
   : _topic_table(topic_table)
-  , _stable_revision_id(_topic_table.local().last_applied_revision())
+  , _stable_revision_id(_topic_table.local().topics_map_revision())
   , _batch_size(batch_size) {
     if (_topic_table.local()._topics.empty()) {
         _topic_iterator = _topic_table.local()._topics.end();
@@ -32,8 +32,7 @@ topic_table_partition_generator::topic_table_partition_generator(
 
 ss::future<std::optional<topic_table_partition_generator::generator_type_t>>
 topic_table_partition_generator::next_batch() {
-    const auto current_revision_id
-      = _topic_table.local().last_applied_revision();
+    const auto current_revision_id = _topic_table.local().topics_map_revision();
     if (current_revision_id != _stable_revision_id) {
         throw topic_table_partition_generator_exception(fmt::format(
           "Last applied revision id moved from {} to {} whilst "