MDEV-18429 Consistent non-locking reads do not appear in TRANSACTIONS section of SHOW ENGINE INNODB STATUS

lock_print_info_all_transactions(): print transactions which are started
but not in RW or RO lists.

print_not_started(): Replaces PrintNotStarted. Collect the skipped
transactions.

1 files changed, 31 insertions, 20 deletions

diff --git a/storage/innobase/lock/lock0lock.cc b/storage/innobase/lock/lock0lock.cc
index 7f6171241ac..22ec2ee7f06 100644
--- a/storage/innobase/lock/lock0lock.cc
+++ b/storage/innobase/lock/lock0lock.cc
@@ -4973,28 +4973,26 @@ lock_print_info_summary(
 	return(TRUE);
 }
 
-/** Functor to print not-started transaction from the mysql_trx_list. */
-
-struct	PrintNotStarted {
-
-	PrintNotStarted(FILE* file) : m_file(file) { }
-
-	void	operator()(const trx_t* trx)
-	{
-		ut_ad(trx->in_mysql_trx_list);
-		ut_ad(mutex_own(&trx_sys->mutex));
+/** Prints not started transaction or puts it into set.
+@param[in]	trx	transaction
+@param[in,out]	file	fd where to print
+@param[in,out]	started	put transaction here if is started */
+static void
+print_not_started(const trx_t* trx, FILE* file, std::set<const trx_t*>& started)
+{
+	ut_ad(trx->in_mysql_trx_list);
+	ut_ad(mutex_own(&trx_sys->mutex));
 
-		/* See state transitions and locking rules in trx0trx.h */
+	/* See state transitions and locking rules in trx0trx.h */
 
-		if (trx_state_eq(trx, TRX_STATE_NOT_STARTED)) {
+	if (trx_state_eq(trx, TRX_STATE_NOT_STARTED)) {
 
-			fputs("---", m_file);
-			trx_print_latched(m_file, trx, 600);
-		}
+		fputs("---", file);
+		trx_print_latched(file, trx, 600);
+	} else {
+		started.insert(trx);
 	}
-
-	FILE*		m_file;
-};
+}
 
 /** Iterate over a transaction's locks. Keeping track of the
 iterator using an ordinal value. */
@@ -5287,8 +5285,11 @@ lock_print_info_all_transactions(
 	transactions will be omitted here. The information will be
 	available from INFORMATION_SCHEMA.INNODB_TRX. */
 
-	PrintNotStarted	print_not_started(file);
-	ut_list_map(trx_sys->mysql_trx_list, print_not_started);
+	std::set<const trx_t*> not_printed_transactions;
+	for (const trx_t* trx = UT_LIST_GET_FIRST(trx_sys->mysql_trx_list);
+	     trx; trx = UT_LIST_GET_NEXT(mysql_trx_list, trx)) {
+		print_not_started(trx, file, not_printed_transactions);
+	}
 
 	const trx_t*	trx;
 	TrxListIterator	trx_iter;
@@ -5302,6 +5303,8 @@ lock_print_info_all_transactions(
 
 		check_trx_state(trx);
 
+		not_printed_transactions.erase(trx);
+
 		if (trx != prev_trx) {
 			lock_trx_print_wait_and_mvcc_state(file, trx);
 			prev_trx = trx;
@@ -5342,6 +5345,14 @@ lock_print_info_all_transactions(
 		trx_iter.next();
 	}
 
+	for (std::set<const trx_t*>::const_iterator it
+	     = not_printed_transactions.begin(),
+	     end = not_printed_transactions.end();
+	     it != end; ++it) {
+		fputs("---", file);
+		trx_print_latched(file, *it, 600);
+	}
+
 	lock_mutex_exit();
 	mutex_exit(&trx_sys->mutex);