MDEV-14756 - Remove trx_sys_t::rw_trx_list

Let lock_print_info_all_transactions() iterate rw_trx_hash instead of rw_trx_list. When printing info of locks for transactions, InnoDB monitor doesn't attempt to read relevant page from disk anymore. The code was prone to race conditions. Note that TrxListIterator didn't work as advertised: it iterated rw_trx_list only.

Author: svoj

storage/innobase/include/trx0trx.h

@@ -368,22 +368,6 @@ trx_print_latched(
 ulint	max_query_len);/*!< in: max query length to print,
 or 0 to use the default max length */
 
-#ifdef WITH_WSREP
-/**********************************************************************//**
-Prints info about a transaction.
-Transaction information may be retrieved without having trx_sys->mutex acquired
-so it may not be completely accurate. The caller must own lock_sys->mutex
-and the trx must have some locks to make sure that it does not escape
-without locking lock_sys->mutex. */
-UNIV_INTERN
-void
-wsrep_trx_print_locking(
-FILE*	f,/*!< in: output stream */
-const trx_t*	trx,/*!< in: transaction */
-ulint	max_query_len)/*!< in: max query length to print,
-or 0 to use the default max length */
-MY_ATTRIBUTE((nonnull));
-#endif /* WITH_WSREP */
 /**********************************************************************//**
 Prints info about a transaction.
 Acquires and releases lock_sys->mutex and trx_sys->mutex. */
@@ -852,7 +836,7 @@ transactions. The trx_sys->mutex prevents a race condition between it
 and lock_trx_release_locks() [invoked by trx_commit()].
 
 * trx_print_low() may access transactions not associated with the current
-thread. The caller must be holding trx_sys->mutex and lock_sys->mutex.
+thread. The caller must be holding lock_sys->mutex.
 
 * When a transaction handle is in the trx_sys->mysql_trx_list or
 trx_sys->trx_list, some of its fields must not be modified without