mtr_t::start(): Remove unused parameters

The parameters bool sync=true, bool read_only=false of mtr_t::start()
were added in
https://github.com/mysql/mysql-server/commit/eca5b0fc17a5bd6d4833d35a0d08c8549dd3b5ec
(MySQL 5.7.3).

The parameter read_only was never used anywhere.
The parameter sync was only copied around, and would be returned
by the unused function mtr_t::is_async().

We do not need this dead code in MariaDB.

storage/innobase/include/mtr0mtr.h

@@ -2,7 +2,7 @@
 
 Copyright (c) 1995, 2017, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2012, Facebook Inc.
-Copyright (c) 2013, 2017, MariaDB Corporation
+Copyright (c) 2013, 2018, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -37,12 +37,6 @@ Created 11/26/1995 Heikki Tuuri
 /** Start a mini-transaction. */
 #define mtr_start(m)		(m)->start()
 
-/** Start a synchronous mini-transaction */
-#define mtr_start_sync(m)	(m)->start(true)
-
-/** Start an asynchronous read-only mini-transaction */
-#define mtr_start_ro(m)	(m)->start(true, true)
-
 /** Commit a mini-transaction. */
 #define mtr_commit(m)		(m)->commit()
 
@@ -223,22 +217,8 @@ struct mtr_t {
 	@param[in]	n_reserved	number of reserved extents */
 	void release_free_extents(ulint n_reserved);
 
-	/** Start a mini-transaction.
-	@param sync		true if it is a synchronous mini-transaction
-	@param read_only	true if read only mini-transaction */
-	void start(bool sync = true, bool read_only = false);
-
-	/** @return whether this is an asynchronous mini-transaction. */
-	bool is_async() const
-	{
-		return(!m_sync);
-	}
-
-	/** Request a future commit to be synchronous. */
-	void set_sync()
-	{
-		m_sync = true;
-	}
+	/** Start a mini-transaction. */
+	void start();
 
 	/** Commit the mini-transaction. */
 	void commit();
@@ -590,9 +570,6 @@ struct mtr_t {
 
 	/** LSN at commit time */
 	volatile lsn_t		m_commit_lsn;
-
-	/** true if it is synchronous mini-transaction */
-	bool			m_sync;
 };
 
 #include "mtr0mtr.ic"

storage/innobase/include/trx0rec.h

@@ -183,8 +183,7 @@ trx_undo_rec_get_partial_row(
 @param[in,out]	trx	transaction
 @param[in]	table	table that is being renamed
 @return	DB_SUCCESS or error code */
-dberr_t
-trx_undo_report_rename(trx_t* trx, const dict_table_t* table)
+dberr_t trx_undo_report_rename(trx_t* trx, const dict_table_t* table)
 	MY_ATTRIBUTE((nonnull, warn_unused_result));
 /***********************************************************************//**
 Writes information to an undo log about an insert, update, or a delete marking

storage/innobase/mtr/mtr0mtr.cc

 /*****************************************************************************
 
 Copyright (c) 1995, 2017, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, MariaDB Corporation.
+Copyright (c) 2017, 2018, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -383,18 +383,8 @@ class mtr_t::Command {
 	/** Constructor.
 	Takes ownership of the mtr->m_impl, is responsible for deleting it.
 	@param[in,out]	mtr	mini-transaction */
-	explicit Command(mtr_t* mtr)
-		:
-		m_locks_released()
-	{
-		init(mtr);
-	}
-
-	void init(mtr_t* mtr)
-	{
-		m_impl = &mtr->m_impl;
-		m_sync = mtr->m_sync;
-	}
+	explicit Command(mtr_t* mtr) : m_impl(&mtr->m_impl), m_locks_released()
+	{}
 
 	/** Destructor */
 	~Command()
@@ -427,9 +417,6 @@ class mtr_t::Command {
 	@return number of bytes to write in finish_write() */
 	ulint prepare_write();
 
-	/** true if it is a sync mini-transaction. */
-	bool			m_sync;
-
 	/** The mini-transaction state. */
 	mtr_t::Impl*		m_impl;
 
@@ -488,18 +475,13 @@ mtr_write_log(
 	log_close();
 }
 
-/** Start a mini-transaction.
-@param sync		true if it is a synchronous mini-transaction
-@param read_only	true if read only mini-transaction */
-void
-mtr_t::start(bool sync, bool read_only)
+/** Start a mini-transaction. */
+void mtr_t::start()
 {
 	UNIV_MEM_INVALID(this, sizeof(*this));
 
 	UNIV_MEM_INVALID(&m_impl, sizeof(m_impl));
 
-	m_sync =  sync;
-
 	m_commit_lsn = 0;
 
 	new(&m_impl.m_log) mtr_buf_t();

storage/innobase/trx/trx0rec.cc

@@ -1932,8 +1932,7 @@ trx_undo_page_report_rename(trx_t* trx, const dict_table_t* table,
 @param[in,out]	trx	transaction
 @param[in]	table	table that is being renamed
 @return	DB_SUCCESS or error code */
-dberr_t
-trx_undo_report_rename(trx_t* trx, const dict_table_t* table)
+dberr_t trx_undo_report_rename(trx_t* trx, const dict_table_t* table)
 {
 	ut_ad(!trx->read_only);
 	ut_ad(trx->id);
@@ -1949,7 +1948,7 @@ trx_undo_report_rename(trx_t* trx, const dict_table_t* table)
 	ut_ad((err == DB_SUCCESS) == (*pundo != NULL));
 	if (trx_undo_t* undo = *pundo) {
 		mtr_t	mtr;
-		mtr.start(trx);
+		mtr.start();
 
 		buf_block_t* block = buf_page_get_gen(
 			page_id_t(undo->space, undo->last_page_no),
@@ -1978,7 +1977,7 @@ trx_undo_report_rename(trx_t* trx, const dict_table_t* table)
 				break;
 			} else {
 				mtr.commit();
-				mtr.start(trx);
+				mtr.start();
 				block = trx_undo_add_page(trx, undo, &mtr);
 				if (!block) {
 					err = DB_OUT_OF_FILE_SPACE;

storage/innobase/trx/trx0trx.cc

@@ -1838,9 +1838,6 @@ trx_commit_low(
 	bool	serialised;
 
 	if (mtr != NULL) {
-
-		mtr->set_sync();
-
 		serialised = trx_write_serialisation_history(trx, mtr);
 
 		/* The following call commits the mini-transaction, making the
@@ -1905,7 +1902,7 @@ trx_commit(
 
 	if (trx->has_logged()) {
 		mtr = &local_mtr;
-		mtr_start_sync(mtr);
+		mtr->start();
 	} else {
 
 		mtr = NULL;
@@ -2566,7 +2563,7 @@ trx_prepare_low(trx_t* trx)
 
 	trx_rseg_t*	rseg = trx->rsegs.m_redo.rseg;
 
-	mtr.start(true);
+	mtr.start();
 
 	/* Change the undo log segment states from TRX_UNDO_ACTIVE to
 	TRX_UNDO_PREPARED: these modifications to the file data