vinyl: split index->version to mem_list_version/range_tree_version

There is a version member in vy_index that is incremented on each
modification of mem list and range tree. Split it to two members
that correspond to mem list and range tree accordingly.

It is needed for more precise tracking of changes in iterators.

src/box/vinyl.c

@@ -492,11 +492,16 @@ struct vy_index {
 	 * appear only in spaces with a single primary index.
 	 */
 	struct tuple_format *upsert_format;
+	/**
+	 * Incremented for each change of the mem list,
+	 * to invalidate iterators.
+	 */
+	uint32_t mem_list_version;
 	/**
 	 * Incremented for each change of the range list,
 	 * to invalidate iterators.
 	 */
-	uint32_t version;
+	uint32_t range_tree_version;
 	/**
 	 * Primary index of the same space or NULL if this index
 	 * is primary. Referenced by each secondary index.
@@ -714,10 +719,14 @@ struct vy_merge_iterator {
 	bool is_primary;
 
 	/* {{{ Range version checking */
-	/* pointer to index->version */
-	const uint32_t *p_index_version;
-	/* copy of index->version to track range tree changes */
-	uint32_t index_version;
+	/* pointer to index->range_tree_version */
+	const uint32_t *p_range_tree_version;
+	/* pointer to index->mem_list_version */
+	const uint32_t *p_mem_list_version;
+	/* copy of index->range_tree_version to track range tree changes */
+	uint32_t range_tree_version;
+	/* copy of index->mem_list_version to track range tree changes */
+	uint32_t mem_list_version;
 	/* pointer to range->version */
 	const uint32_t *p_range_version;
 	/* copy of curr_range->version to track mem/run lists changes */
@@ -1724,7 +1733,7 @@ vy_index_rotate_mem(struct vy_index *index)
 
 	rlist_add_entry(&index->sealed, index->mem, in_sealed);
 	index->mem = mem;
-	index->version++;
+	index->mem_list_version++;
 
 	vy_scheduler_add_mem(scheduler, mem);
 	return 0;
@@ -1923,7 +1932,7 @@ vy_range_maybe_split(struct vy_range *range)
 		vy_index_acct_range(index, part);
 		vy_scheduler_add_range(scheduler, part);
 	}
-	index->version++;
+	index->range_tree_version++;
 
 	say_info("%s: split range %s by key %s", vy_index_name(index),
 		 vy_range_str(range), vy_key_str(split_key_raw));
@@ -2173,7 +2182,7 @@ vy_range_maybe_coalesce(struct vy_range *range)
 	result->compact_priority = result->slice_count;
 	vy_index_acct_range(index, result);
 	vy_index_add_range(index, result);
-	index->version++;
+	index->range_tree_version++;
 	vy_scheduler_add_range(scheduler, result);
 
 	say_info("%s: coalesced ranges %s",
@@ -3075,7 +3084,7 @@ vy_task_dump_complete(struct vy_task *task)
 		vy_scheduler_remove_mem(scheduler, mem);
 		vy_mem_delete(mem);
 	}
-	index->version++;
+	index->mem_list_version++;
 	index->dump_lsn = dump_lsn;
 	index->generation = task->generation;
 	index->stat.disk.dump.count++;
@@ -7123,9 +7132,11 @@ vy_merge_iterator_open(struct vy_merge_iterator *itr,
 	itr->format = format;
 	itr->upsert_format = upsert_format;
 	itr->is_primary = is_primary;
-	itr->index_version = 0;
+	itr->range_tree_version = 0;
+	itr->p_mem_list_version = 0;
 	itr->range_version = 0;
-	itr->p_index_version = NULL;
+	itr->p_range_tree_version = NULL;
+	itr->p_mem_list_version = NULL;
 	itr->p_range_version = NULL;
 	itr->key = key;
 	itr->iterator_type = iterator_type;
@@ -7167,9 +7178,11 @@ vy_merge_iterator_cleanup(struct vy_merge_iterator *itr)
 	}
 	itr->src_capacity = 0;
 	itr->range_version = 0;
-	itr->index_version = 0;
-	itr->p_index_version = NULL;
+	itr->range_tree_version = 0;
+	itr->mem_list_version = 0;
 	itr->p_range_version = NULL;
+	itr->p_range_tree_version = NULL;
+	itr->p_mem_list_version = NULL;
 }
 
 /**
@@ -7250,12 +7263,16 @@ vy_merge_iterator_add(struct vy_merge_iterator *itr,
  */
 static void
 vy_merge_iterator_set_version(struct vy_merge_iterator *itr,
-			      const uint32_t *p_index_version,
+			      const uint32_t *p_range_tree_version,
+			      const uint32_t *p_mem_list_version,
 			      const uint32_t *p_range_version)
 {
-	itr->p_index_version = p_index_version;
-	if (itr->p_index_version != NULL)
-		itr->index_version = *p_index_version;
+	itr->p_range_tree_version = p_range_tree_version;
+	if (itr->p_range_tree_version != NULL)
+		itr->range_tree_version = *p_range_tree_version;
+	itr->p_mem_list_version = p_mem_list_version;
+	if (itr->p_mem_list_version != NULL)
+		itr->mem_list_version = *p_mem_list_version;
 	itr->p_range_version = p_range_version;
 	if (itr->p_range_version != NULL)
 		itr->range_version = *p_range_version;
@@ -7269,8 +7286,11 @@ vy_merge_iterator_set_version(struct vy_merge_iterator *itr,
 static NODISCARD int
 vy_merge_iterator_check_version(struct vy_merge_iterator *itr)
 {
-	if (itr->p_index_version != NULL &&
-	    *itr->p_index_version != itr->index_version)
+	if (itr->p_range_tree_version != NULL &&
+	    *itr->p_range_tree_version != itr->range_tree_version)
+		return -2;
+	if (itr->p_mem_list_version != NULL &&
+	    *itr->p_mem_list_version != itr->mem_list_version)
 		return -2;
 	if (itr->p_range_version != NULL &&
 	    *itr->p_range_version != itr->range_version)
@@ -7689,7 +7709,8 @@ vy_read_iterator_use_range(struct vy_read_iterator *itr)
 
 	/* Enable range and range index version checks */
 	vy_merge_iterator_set_version(&itr->merge_iterator,
-				      &itr->index->version,
+				      &itr->index->range_tree_version,
+				      &itr->index->mem_list_version,
 				      itr->curr_range != NULL ?
 				      &itr->curr_range->version : NULL);
 }