MDEV-6928: Add trx pointer to struct mtr_t

Merge Facebook commit 25295d003c
authored by Steaphan Greene from https://github.com/facebook/mysql-5.6

This adds a pointer to the trx to each mtr.
This allows the trx to be accessed in parts of the code
where it was otherwise not available. This is needed later.

storage/innobase/api/api0api.cc

@@ -427,7 +427,7 @@ ib_read_tuple(
 
 			data = btr_rec_copy_externally_stored_field(
 				copy, offsets, zip_size, i, &len,
-				tuple->heap);
+				tuple->heap, NULL);
 
 			ut_a(len != UNIV_SQL_NULL);
 		}

storage/innobase/btr/btr0cur.cc

@@ -3610,7 +3610,8 @@ btr_estimate_n_rows_in_range(
 	const dtuple_t*	tuple1,	/*!< in: range start, may also be empty tuple */
 	ulint		mode1,	/*!< in: search mode for range start */
 	const dtuple_t*	tuple2,	/*!< in: range end, may also be empty tuple */
-	ulint		mode2)	/*!< in: search mode for range end */
+	ulint		mode2,	/*!< in: search mode for range end */
+	trx_t*		trx)	/*!< in: trx */
 {
 	btr_path_t	path1[BTR_PATH_ARRAY_N_SLOTS];
 	btr_path_t	path2[BTR_PATH_ARRAY_N_SLOTS];
@@ -3628,7 +3629,7 @@ btr_estimate_n_rows_in_range(
 
 	table_n_rows = dict_table_get_n_rows(index->table);
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	cursor.path_arr = path1;
 
@@ -3646,7 +3647,7 @@ btr_estimate_n_rows_in_range(
 
 	mtr_commit(&mtr);
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	cursor.path_arr = path2;
 
@@ -5228,7 +5229,8 @@ btr_copy_blob_prefix(
 	ulint		len,	/*!< in: length of buf, in bytes */
 	ulint		space_id,/*!< in: space id of the BLOB pages */
 	ulint		page_no,/*!< in: page number of the first BLOB page */
-	ulint		offset)	/*!< in: offset on the first BLOB page */
+	ulint		offset,	/*!< in: offset on the first BLOB page */
+	trx_t*		trx)	/*!< in: transaction handle */
 {
 	ulint	copied_len	= 0;
 
@@ -5240,7 +5242,7 @@ btr_copy_blob_prefix(
 		ulint		part_len;
 		ulint		copy_len;
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 
 		block = buf_page_get(space_id, 0, page_no, RW_S_LATCH, &mtr);
 		buf_block_dbg_add_level(block, SYNC_EXTERN_STORAGE);
@@ -5443,7 +5445,8 @@ btr_copy_externally_stored_field_prefix_low(
 				zero for uncompressed BLOBs */
 	ulint		space_id,/*!< in: space id of the first BLOB page */
 	ulint		page_no,/*!< in: page number of the first BLOB page */
-	ulint		offset)	/*!< in: offset on the first BLOB page */
+	ulint		offset,	/*!< in: offset on the first BLOB page */
+	trx_t*		trx)	/*!< in: transaction handle */
 {
 	if (UNIV_UNLIKELY(len == 0)) {
 		return(0);
@@ -5454,7 +5457,7 @@ btr_copy_externally_stored_field_prefix_low(
 					     space_id, page_no, offset));
 	} else {
 		return(btr_copy_blob_prefix(buf, len, space_id,
-					    page_no, offset));
+					    page_no, offset, trx));
 	}
 }
 
@@ -5475,7 +5478,8 @@ btr_copy_externally_stored_field_prefix(
 				field containing also the reference to
 				the external part; must be protected by
 				a lock or a page latch */
-	ulint		local_len)/*!< in: length of data, in bytes */
+	ulint		local_len,/*!< in: length of data, in bytes */
+	trx_t*		trx)	/*!< in: transaction handle */
 {
 	ulint	space_id;
 	ulint	page_no;
@@ -5514,7 +5518,7 @@ btr_copy_externally_stored_field_prefix(
 							     len - local_len,
 							     zip_size,
 							     space_id, page_no,
-							     offset));
+							     offset, trx));
 }
 
 /*******************************************************************//**
@@ -5533,7 +5537,8 @@ btr_copy_externally_stored_field(
 	ulint		zip_size,/*!< in: nonzero=compressed BLOB page size,
 				zero for uncompressed BLOBs */
 	ulint		local_len,/*!< in: length of data */
-	mem_heap_t*	heap)	/*!< in: mem heap */
+	mem_heap_t*	heap,	/*!< in: mem heap */
+	trx_t*		trx)	/*!< in: transaction handle */
 {
 	ulint	space_id;
 	ulint	page_no;
@@ -5564,7 +5569,8 @@ btr_copy_externally_stored_field(
 							      extern_len,
 							      zip_size,
 							      space_id,
-							      page_no, offset);
+							      page_no, offset,
+							      trx);
 
 	return(buf);
 }
@@ -5583,7 +5589,8 @@ btr_rec_copy_externally_stored_field(
 				zero for uncompressed BLOBs */
 	ulint		no,	/*!< in: field number */
 	ulint*		len,	/*!< out: length of the field */
-	mem_heap_t*	heap)	/*!< in: mem heap */
+	mem_heap_t*	heap,	/*!< in: mem heap */
+	trx_t*		trx)	/*!< in: transaction handle */
 {
 	ulint		local_len;
 	const byte*	data;
@@ -5614,6 +5621,7 @@ btr_rec_copy_externally_stored_field(
 	}
 
 	return(btr_copy_externally_stored_field(len, data,
-						zip_size, local_len, heap));
+						zip_size, local_len, heap,
+						trx));
 }
 #endif /* !UNIV_HOTBACKUP */

storage/innobase/btr/btr0pcur.cc

@@ -486,7 +486,7 @@ btr_pcur_move_backward_from_page(
 
 	mtr_commit(mtr);
 
-	mtr_start(mtr);
+	mtr_start_trx(mtr, mtr->trx);
 
 	btr_pcur_restore_position(latch_mode2, cursor, mtr);
 

storage/innobase/fts/fts0fts.cc

@@ -3393,7 +3393,8 @@ fts_fetch_doc_from_rec(
 					dict_table_zip_size(table),
 					clust_pos, &doc->text.f_len,
 					static_cast<mem_heap_t*>(
-						doc->self_heap->arg));
+						doc->self_heap->arg),
+					NULL);
 		} else {
 			doc->text.f_str = (byte*) rec_get_nth_field(
 				clust_rec, offsets, clust_pos,
@@ -7077,7 +7078,8 @@ fts_init_recover_doc(
 				&doc.text.f_len,
 				static_cast<byte*>(dfield_get_data(dfield)),
 				zip_size, len,
-				static_cast<mem_heap_t*>(doc.self_heap->arg));
+				static_cast<mem_heap_t*>(doc.self_heap->arg),
+				NULL);
 		} else {
 			doc.text.f_str = static_cast<byte*>(
 				dfield_get_data(dfield));

storage/innobase/fts/fts0que.cc

@@ -1918,7 +1918,8 @@ fts_query_fetch_document(
 		if (dfield_is_ext(dfield)) {
 			data = btr_copy_externally_stored_field(
 				&cur_len, data, phrase->zip_size,
-				dfield_get_len(dfield), phrase->heap);
+				dfield_get_len(dfield), phrase->heap,
+				NULL);
 		} else {
 			cur_len = dfield_get_len(dfield);
 		}

storage/innobase/handler/ha_innodb.cc

@@ -10842,7 +10842,7 @@ ha_innobase::records_in_range(
 
 		n_rows = btr_estimate_n_rows_in_range(index, range_start,
 						      mode1, range_end,
-						      mode2);
+						      mode2, prebuilt->trx);
 	} else {
 
 		n_rows = HA_POS_ERROR;

storage/innobase/include/btr0cur.h

@@ -561,7 +561,8 @@ btr_estimate_n_rows_in_range(
 	const dtuple_t*	tuple1,	/*!< in: range start, may also be empty tuple */
 	ulint		mode1,	/*!< in: search mode for range start */
 	const dtuple_t*	tuple2,	/*!< in: range end, may also be empty tuple */
-	ulint		mode2);	/*!< in: search mode for range end */
+	ulint		mode2,	/*!< in: search mode for range end */
+	trx_t*		trx);	/*!< in: trx */
 /*******************************************************************//**
 Estimates the number of different key values in a given index, for
 each n-column prefix of the index where 1 <= n <= dict_index_get_n_unique(index).
@@ -697,7 +698,8 @@ btr_copy_externally_stored_field_prefix(
 				field containing also the reference to
 				the external part; must be protected by
 				a lock or a page latch */
-	ulint		local_len);/*!< in: length of data, in bytes */
+	ulint		local_len,/*!< in: length of data, in bytes */
+	trx_t*		trx);	/*!< in: transaction handle */
 /*******************************************************************//**
 Copies an externally stored field of a record to mem heap.  The
 clustered index record must be protected by a lock or a page latch.
@@ -714,7 +716,8 @@ btr_copy_externally_stored_field(
 	ulint		zip_size,/*!< in: nonzero=compressed BLOB page size,
 				zero for uncompressed BLOBs */
 	ulint		local_len,/*!< in: length of data */
-	mem_heap_t*	heap);	/*!< in: mem heap */
+	mem_heap_t*	heap,	/*!< in: mem heap */
+	trx_t*		trx);	/*!< in: transaction handle */
 /*******************************************************************//**
 Copies an externally stored field of a record to mem heap.
 @return	the field copied to heap, or NULL if the field is incomplete */
@@ -729,7 +732,8 @@ btr_rec_copy_externally_stored_field(
 				zero for uncompressed BLOBs */
 	ulint		no,	/*!< in: field number */
 	ulint*		len,	/*!< out: length of the field */
-	mem_heap_t*	heap);	/*!< in: mem heap */
+	mem_heap_t*	heap,	/*!< in: mem heap */
+	trx_t*		trx);	/*!< in: transaction handle */
 /*******************************************************************//**
 Flags the data tuple fields that are marked as extern storage in the
 update vector.  We use this function to remember which fields we must

storage/innobase/include/mtr0mtr.h

@@ -35,6 +35,7 @@ Created 11/26/1995 Heikki Tuuri
 #include "ut0byte.h"
 #include "mtr0types.h"
 #include "page0types.h"
+#include "trx0types.h"
 
 /* Logging modes for a mini-transaction */
 #define MTR_LOG_ALL		21	/* default mode: log all operations
@@ -200,6 +201,15 @@ functions).  The page number parameter was originally written as 0. @{ */
 /* included here because it needs MLOG_LSN defined */
 #include "log0log.h"
 
+/***************************************************************//**
+Starts a mini-transaction. */
+UNIV_INLINE
+void
+mtr_start_trx(
+/*======*/
+	mtr_t*	mtr,	/*!< out: mini-transaction */
+	trx_t*	trx)	/*!< in: transaction */
+	__attribute__((nonnull (1)));
 /***************************************************************//**
 Starts a mini-transaction. */
 UNIV_INLINE
@@ -207,7 +217,10 @@ void
 mtr_start(
 /*======*/
 	mtr_t*	mtr)	/*!< out: mini-transaction */
-	__attribute__((nonnull));
+{
+	mtr_start_trx(mtr, NULL);
+}
+	__attribute__((nonnull))
 /***************************************************************//**
 Commits a mini-transaction. */
 UNIV_INTERN
@@ -403,6 +416,7 @@ struct mtr_t{
 #ifdef UNIV_DEBUG
 	ulint		magic_n;
 #endif /* UNIV_DEBUG */
+	trx_t*		trx;	/*!< transaction */
 };
 
 #ifdef UNIV_DEBUG

storage/innobase/include/mtr0mtr.ic

@@ -43,9 +43,10 @@ mtr_block_dirtied(
 Starts a mini-transaction. */
 UNIV_INLINE
 void
-mtr_start(
+mtr_start_trx(
 /*======*/
-	mtr_t*	mtr)	/*!< out: mini-transaction */
+	mtr_t*	mtr,	/*!< out: mini-transaction */
+	trx_t*	trx)	/*!< in: transaction */
 {
 	UNIV_MEM_INVALID(mtr, sizeof *mtr);
 
@@ -58,6 +59,7 @@ mtr_start(
 	mtr->made_dirty = FALSE;
 	mtr->n_log_recs = 0;
 	mtr->n_freed_pages = 0;
+	mtr->trx = trx;
 
 	ut_d(mtr->state = MTR_ACTIVE);
 	ut_d(mtr->magic_n = MTR_MAGIC_N);

storage/innobase/include/trx0undo.h

@@ -243,22 +243,13 @@ Truncates an undo log from the end. This function is used during a rollback
 to free space from an undo log. */
 UNIV_INTERN
 void
-trx_undo_truncate_end_func(
+trx_undo_truncate_end(
 /*=======================*/
-#ifdef UNIV_DEBUG
-	const trx_t*	trx,	/*!< in: transaction whose undo log it is */
-#endif /* UNIV_DEBUG */
+	trx_t*		trx,	/*!< in: transaction whose undo log it is */
 	trx_undo_t*	undo,	/*!< in/out: undo log */
 	undo_no_t	limit)	/*!< in: all undo records with undo number
 				>= this value should be truncated */
 	__attribute__((nonnull));
-#ifdef UNIV_DEBUG
-# define trx_undo_truncate_end(trx,undo,limit)		\
-	trx_undo_truncate_end_func(trx,undo,limit)
-#else /* UNIV_DEBUG */
-# define trx_undo_truncate_end(trx,undo,limit)		\
-	trx_undo_truncate_end_func(undo,limit)
-#endif /* UNIV_DEBUG */
 
 /***********************************************************************//**
 Truncates an undo log from the start. This function is used during a purge

storage/innobase/row/row0ext.cc

@@ -78,7 +78,8 @@ row_ext_cache_fill(
 			crashed during the execution of
 			btr_free_externally_stored_field(). */
 			ext->len[i] = btr_copy_externally_stored_field_prefix(
-				buf, ext->max_len, zip_size, field, f_len);
+				buf, ext->max_len, zip_size, field, f_len,
+				NULL);
 		}
 	}
 }

storage/innobase/row/row0ftsort.cc

@@ -660,7 +660,8 @@ loop:
 				doc.text.f_str =
 					btr_copy_externally_stored_field(
 						&doc.text.f_len, data,
-						zip_size, data_len, blob_heap);
+						zip_size, data_len, blob_heap,
+						NULL);
 			} else {
 				doc.text.f_str = data;
 				doc.text.f_len = data_len;

storage/innobase/row/row0ins.cc

@@ -1294,7 +1294,7 @@ row_ins_foreign_check_on_constraint(
 
 	row_mysql_freeze_data_dictionary(thr_get_trx(thr));
 
-	mtr_start(mtr);
+	mtr_start_trx(mtr, trx);
 
 	/* Restore pcur position */
 
@@ -1322,7 +1322,7 @@ nonstandard_exit_func:
 	btr_pcur_store_position(pcur, mtr);
 
 	mtr_commit(mtr);
-	mtr_start(mtr);
+	mtr_start_trx(mtr, trx);
 
 	btr_pcur_restore_position(BTR_SEARCH_LEAF, pcur, mtr);
 
@@ -1530,7 +1530,7 @@ run_again:
 		}
 	}
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	/* Store old value on n_fields_cmp */
 
@@ -2331,7 +2331,7 @@ row_ins_clust_index_entry_low(
 	      || n_uniq == dict_index_get_n_unique(index));
 	ut_ad(!n_uniq || n_uniq == dict_index_get_n_unique(index));
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	if (mode == BTR_MODIFY_LEAF && dict_index_is_online_ddl(index)) {
 		mode = BTR_MODIFY_LEAF | BTR_ALREADY_S_LATCHED;
@@ -2544,9 +2544,10 @@ Starts a mini-transaction and checks if the index will be dropped.
 @return true if the index is to be dropped */
 static __attribute__((nonnull, warn_unused_result))
 bool
-row_ins_sec_mtr_start_and_check_if_aborted(
+row_ins_sec_mtr_start_trx_and_check_if_aborted(
 /*=======================================*/
 	mtr_t*		mtr,	/*!< out: mini-transaction */
+	trx_t*		trx,	/*!< in: transaction handle */
 	dict_index_t*	index,	/*!< in/out: secondary index */
 	bool		check,	/*!< in: whether to check */
 	ulint		search_mode)
@@ -2554,7 +2555,7 @@ row_ins_sec_mtr_start_and_check_if_aborted(
 {
 	ut_ad(!dict_index_is_clust(index));
 
-	mtr_start(mtr);
+	mtr_start_trx(mtr, trx);
 
 	if (!check) {
 		return(false);
@@ -2612,13 +2613,14 @@ row_ins_sec_index_entry_low(
 	ulint		n_unique;
 	mtr_t		mtr;
 	ulint*		offsets	= NULL;
+	trx_t*		trx = thr_get_trx(thr);
 
 	ut_ad(!dict_index_is_clust(index));
 	ut_ad(mode == BTR_MODIFY_LEAF || mode == BTR_MODIFY_TREE);
 
 	cursor.thr = thr;
 	ut_ad(thr_get_trx(thr)->id);
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	/* Ensure that we acquire index->lock when inserting into an
 	index with index->online_status == ONLINE_INDEX_COMPLETE, but
@@ -2679,8 +2681,8 @@ row_ins_sec_index_entry_low(
 
 		DEBUG_SYNC_C("row_ins_sec_index_unique");
 
-		if (row_ins_sec_mtr_start_and_check_if_aborted(
-			    &mtr, index, check, search_mode)) {
+		if (row_ins_sec_mtr_start_trx_and_check_if_aborted(
+			    &mtr, trx, index, check, search_mode)) {
 			goto func_exit;
 		}
 
@@ -2714,8 +2716,8 @@ row_ins_sec_index_entry_low(
 			return(err);
 		}
 
-		if (row_ins_sec_mtr_start_and_check_if_aborted(
-			    &mtr, index, check, search_mode)) {
+		if (row_ins_sec_mtr_start_trx_and_check_if_aborted(
+			    &mtr, trx, index, check, search_mode)) {
 			goto func_exit;
 		}
 

storage/innobase/row/row0log.cc

@@ -980,7 +980,7 @@ row_log_table_get_pk_col(
 			mem_heap_alloc(heap, field_len));
 
 		len = btr_copy_externally_stored_field_prefix(
-			blob_field, field_len, zip_size, field, len);
+			blob_field, field_len, zip_size, field, len, NULL);
 		if (len >= max_len + 1) {
 			return(DB_TOO_BIG_INDEX_COL);
 		}
@@ -1371,7 +1371,7 @@ row_log_table_apply_convert_mrec(
 			data = btr_rec_copy_externally_stored_field(
 				mrec, offsets,
 				dict_table_zip_size(index->table),
-				i, &len, heap);
+				i, &len, heap, NULL);
 			ut_a(data);
 			dfield_set_data(dfield, data, len);
 blob_done:

storage/innobase/row/row0merge.cc

@@ -2246,7 +2246,7 @@ row_merge_copy_blobs(
 		BLOB pointers are read (row_merge_read_clustered_index())
 		and dereferenced (below). */
 		data = btr_rec_copy_externally_stored_field(
-			mrec, offsets, zip_size, i, &len, heap);
+			mrec, offsets, zip_size, i, &len, heap, NULL);
 		/* Because we have locked the table, any records
 		written by incomplete transactions must have been
 		rolled back already. There must not be any incomplete

storage/innobase/row/row0mysql.cc

@@ -1850,7 +1850,7 @@ row_unlock_for_mysql(
 		trx_id_t	rec_trx_id;
 		mtr_t		mtr;
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 
 		/* Restore the cursor position and find the record */
 
@@ -3412,7 +3412,7 @@ row_truncate_table_for_mysql(
 				index = dict_table_get_next_index(index);
 			} while (index);
 
-			mtr_start(&mtr);
+			mtr_start_trx(&mtr, trx);
 			fsp_header_init(space,
 					FIL_IBD_FILE_INITIAL_SIZE, &mtr);
 			mtr_commit(&mtr);
@@ -3441,7 +3441,7 @@ row_truncate_table_for_mysql(
 	sys_index = dict_table_get_first_index(dict_sys->sys_indexes);
 	dict_index_copy_types(tuple, sys_index, 1);
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 	btr_pcur_open_on_user_rec(sys_index, tuple, PAGE_CUR_GE,
 				  BTR_MODIFY_LEAF, &pcur, &mtr);
 	for (;;) {
@@ -3488,7 +3488,7 @@ row_truncate_table_for_mysql(
 			a page in this mini-transaction, and the rest of
 			this loop could latch another index page. */
 			mtr_commit(&mtr);
-			mtr_start(&mtr);
+			mtr_start_trx(&mtr, trx);
 			btr_pcur_restore_position(BTR_MODIFY_LEAF,
 						  &pcur, &mtr);
 		}

storage/innobase/row/row0sel.cc

@@ -132,7 +132,8 @@ row_sel_sec_rec_is_for_blob(
 
 	len = btr_copy_externally_stored_field_prefix(buf, prefix_len,
 						      zip_size,
-						      clust_field, clust_len);
+						      clust_field, clust_len,
+						      NULL);
 
 	if (UNIV_UNLIKELY(len == 0)) {
 		/* The BLOB was being deleted as the server crashed.
@@ -451,7 +452,7 @@ row_sel_fetch_columns(
 				data = btr_rec_copy_externally_stored_field(
 					rec, offsets,
 					dict_table_zip_size(index->table),
-					field_no, &len, heap);
+					field_no, &len, heap, NULL);
 
 				/* data == NULL means that the
 				externally stored field was not
@@ -1398,7 +1399,7 @@ table_loop:
 
 	/* Open a cursor to index, or restore an open cursor position */
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	if (consistent_read && plan->unique_search && !plan->pcur_is_open
 	    && !plan->must_get_clust
@@ -1438,7 +1439,7 @@ table_loop:
 		plan_reset_cursor(plan);
 
 		mtr_commit(&mtr);
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, thr_get_trx(thr));
 	}
 
 	if (search_latch_locked) {
@@ -2809,7 +2810,7 @@ row_sel_store_mysql_field_func(
 		data = btr_rec_copy_externally_stored_field(
 			rec, offsets,
 			dict_table_zip_size(prebuilt->table),
-			field_no, &len, heap);
+			field_no, &len, heap, NULL);
 
 		if (UNIV_UNLIKELY(!data)) {
 			/* The externally stored field was not written
@@ -3885,7 +3886,7 @@ row_search_for_mysql(
 		}
 	}
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	/*-------------------------------------------------------------*/
 	/* PHASE 2: Try fast adaptive hash index search if possible */
@@ -4015,7 +4016,7 @@ release_search_latch_if_needed:
 			}
 
 			mtr_commit(&mtr);
-			mtr_start(&mtr);
+			mtr_start_trx(&mtr, trx);
 		}
 	}
 
@@ -5002,7 +5003,7 @@ next_rec:
 		mtr_commit(&mtr);
 		mtr_has_extra_clust_latch = FALSE;
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 		if (sel_restore_position_for_mysql(&same_user_rec,
 						   BTR_SEARCH_LEAF,
 						   pcur, moves_up, &mtr)) {
@@ -5067,7 +5068,7 @@ lock_table_wait:
 		/* It was a lock wait, and it ended */
 
 		thr->lock_state = QUE_THR_LOCK_NOLOCK;
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 
 		/* Table lock waited, go try to obtain table lock
 		again */

storage/innobase/row/row0umod.cc

@@ -297,7 +297,7 @@ row_undo_mod_clust(
 	pcur = &node->pcur;
 	index = btr_cur_get_index(btr_pcur_get_btr_cur(pcur));
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	online = dict_index_is_online_ddl(index);
 	if (online) {
@@ -326,7 +326,7 @@ row_undo_mod_clust(
 		/* We may have to modify tree structure: do a pessimistic
 		descent down the index tree */
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, thr_get_trx(thr));
 
 		err = row_undo_mod_clust_low(
 			node, &offsets, &offsets_heap,
@@ -371,7 +371,7 @@ row_undo_mod_clust(
 
 	if (err == DB_SUCCESS && node->rec_type == TRX_UNDO_UPD_DEL_REC) {
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, thr_get_trx(thr));
 
 		/* It is not necessary to call row_log_table,
 		because the record is delete-marked and would thus
@@ -384,7 +384,7 @@ row_undo_mod_clust(
 			/* We may have to modify tree structure: do a
 			pessimistic descent down the index tree */
 
-			mtr_start(&mtr);
+			mtr_start_trx(&mtr, thr_get_trx(thr));
 
 			err = row_undo_mod_remove_clust_low(node, thr, &mtr,
 							    BTR_MODIFY_TREE);
@@ -431,7 +431,7 @@ row_undo_mod_del_mark_or_remove_sec_low(
 	enum row_search_result	search_result;
 
 	log_free_check();
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	if (*index->name == TEMP_INDEX_PREFIX) {
 		/* The index->online_status may change if the
@@ -487,7 +487,7 @@ row_undo_mod_del_mark_or_remove_sec_low(
 	which cannot be purged yet, requires its existence. If some requires,
 	we should delete mark the record. */
 
-	mtr_start(&mtr_vers);
+	mtr_start_trx(&mtr_vers, thr_get_trx(thr));
 
 	success = btr_pcur_restore_position(BTR_SEARCH_LEAF, &(node->pcur),
 					    &mtr_vers);
@@ -603,7 +603,7 @@ row_undo_mod_del_unmark_sec_and_undo_update(
 	ut_ad(trx->id);
 
 	log_free_check();
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	if (*index->name == TEMP_INDEX_PREFIX) {
 		/* The index->online_status may change if the

storage/innobase/row/row0upd.cc

@@ -210,7 +210,7 @@ row_upd_check_references_constraints(
 
 	DEBUG_SYNC_C("foreign_constraint_check_for_update");
 
-	mtr_start(mtr);
+	mtr_start_trx(mtr, trx);
 
 	if (trx->dict_operation_lock_mode == 0) {
 		got_s_lock = TRUE;
@@ -984,7 +984,7 @@ row_upd_ext_fetch(
 	byte*	buf = static_cast<byte*>(mem_heap_alloc(heap, *len));
 
 	*len = btr_copy_externally_stored_field_prefix(
-		buf, *len, zip_size, data, local_len);
+		buf, *len, zip_size, data, local_len, NULL);
 
 	/* We should never update records containing a half-deleted BLOB. */
 	ut_a(*len);
@@ -1685,7 +1685,7 @@ row_upd_sec_index_entry(
 	}
 #endif /* UNIV_DEBUG */
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	if (*index->name == TEMP_INDEX_PREFIX) {
 		/* The index->online_status may change if the
@@ -2152,7 +2152,7 @@ row_upd_clust_rec(
 	/* We may have to modify the tree structure: do a pessimistic descent
 	down the index tree */
 
-	mtr_start(mtr);
+	mtr_start_trx(mtr, thr_get_trx(thr));
 
 	/* NOTE: this transaction has an s-lock or x-lock on the record and
 	therefore other transactions cannot modify the record when we have no
@@ -2319,7 +2319,7 @@ row_upd_clust_step(
 
 	/* We have to restore the cursor to its position */
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	/* If the restoration does not succeed, then the same
 	transaction has deleted the record on which the cursor was,
@@ -2373,7 +2373,7 @@ row_upd_clust_step(
 
 		mtr_commit(&mtr);
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, thr_get_trx(thr));
 
 		success = btr_pcur_restore_position(BTR_MODIFY_LEAF, pcur,
 						    &mtr);

storage/innobase/trx/trx0rec.cc

@@ -466,7 +466,7 @@ trx_undo_page_fetch_ext(
 {
 	/* Fetch the BLOB. */
 	ulint	ext_len = btr_copy_externally_stored_field_prefix(
-		ext_buf, prefix_len, zip_size, field, *len);
+		ext_buf, prefix_len, zip_size, field, *len, NULL);
 	/* BLOBs should always be nonempty. */
 	ut_a(ext_len);
 	/* Append the BLOB pointer to the prefix. */
@@ -1247,7 +1247,7 @@ trx_undo_report_row_operation(
 
 	rseg = trx->rseg;
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 	mutex_enter(&trx->undo_mutex);
 
 	/* If the undo log is not assigned yet, assign one */
@@ -1336,7 +1336,7 @@ trx_undo_report_row_operation(
 				latches, such as SYNC_FSP and SYNC_FSP_PAGE. */
 
 				mtr_commit(&mtr);
-				mtr_start(&mtr);
+				mtr_start_trx(&mtr, trx);
 
 				mutex_enter(&rseg->mutex);
 				trx_undo_free_last_page(trx, undo, &mtr);
@@ -1373,7 +1373,7 @@ trx_undo_report_row_operation(
 		/* We have to extend the undo log by one page */
 
 		ut_ad(++loop_count < 2);
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 
 		/* When we add a page to an undo log, this is analogous to
 		a pessimistic insert in a B-tree, and we must reserve the

storage/innobase/trx/trx0undo.cc

@@ -1067,11 +1067,9 @@ Truncates an undo log from the end. This function is used during a rollback
 to free space from an undo log. */
 UNIV_INTERN
 void
-trx_undo_truncate_end_func(
+trx_undo_truncate_end(
 /*=======================*/
-#ifdef UNIV_DEBUG
-	const trx_t*	trx,	/*!< in: transaction whose undo log it is */
-#endif /* UNIV_DEBUG */
+	trx_t*		trx,	/*!< in: transaction whose undo log it is */
 	trx_undo_t*	undo,	/*!< in: undo log */
 	undo_no_t	limit)	/*!< in: all undo records with undo number
 				>= this value should be truncated */
@@ -1086,7 +1084,7 @@ trx_undo_truncate_end_func(
 	ut_ad(mutex_own(&(trx->rseg->mutex)));
 
 	for (;;) {
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 
 		trunc_here = NULL;
 
@@ -1773,7 +1771,7 @@ trx_undo_assign_undo(
 
 	ut_ad(mutex_own(&(trx->undo_mutex)));
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	mutex_enter(&rseg->mutex);
 

storage/xtradb/api/api0api.cc

@@ -427,7 +427,7 @@ ib_read_tuple(
 
 			data = btr_rec_copy_externally_stored_field(
 				copy, offsets, zip_size, i, &len,
-				tuple->heap);
+				tuple->heap, NULL);
 
 			ut_a(len != UNIV_SQL_NULL);
 		}

storage/xtradb/btr/btr0cur.cc

@@ -3801,7 +3801,8 @@ btr_estimate_n_rows_in_range(
 	const dtuple_t*	tuple1,	/*!< in: range start, may also be empty tuple */
 	ulint		mode1,	/*!< in: search mode for range start */
 	const dtuple_t*	tuple2,	/*!< in: range end, may also be empty tuple */
-	ulint		mode2)	/*!< in: search mode for range end */
+	ulint		mode2,	/*!< in: search mode for range end */
+	trx_t*		trx)	/*!< in: trx */
 {
 	btr_path_t	path1[BTR_PATH_ARRAY_N_SLOTS];
 	btr_path_t	path2[BTR_PATH_ARRAY_N_SLOTS];
@@ -3819,7 +3820,7 @@ btr_estimate_n_rows_in_range(
 
 	table_n_rows = dict_table_get_n_rows(index->table);
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	cursor.path_arr = path1;
 
@@ -3837,7 +3838,7 @@ btr_estimate_n_rows_in_range(
 
 	mtr_commit(&mtr);
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	cursor.path_arr = path2;
 
@@ -5430,7 +5431,8 @@ btr_copy_blob_prefix(
 	ulint		len,	/*!< in: length of buf, in bytes */
 	ulint		space_id,/*!< in: space id of the BLOB pages */
 	ulint		page_no,/*!< in: page number of the first BLOB page */
-	ulint		offset)	/*!< in: offset on the first BLOB page */
+	ulint		offset,	/*!< in: offset on the first BLOB page */
+	trx_t*		trx)	/*!< in: transaction handle */
 {
 	ulint	copied_len	= 0;
 
@@ -5442,7 +5444,7 @@ btr_copy_blob_prefix(
 		ulint		part_len;
 		ulint		copy_len;
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 
 		block = buf_page_get(space_id, 0, page_no, RW_S_LATCH, &mtr);
 		buf_block_dbg_add_level(block, SYNC_EXTERN_STORAGE);
@@ -5645,7 +5647,8 @@ btr_copy_externally_stored_field_prefix_low(
 				zero for uncompressed BLOBs */
 	ulint		space_id,/*!< in: space id of the first BLOB page */
 	ulint		page_no,/*!< in: page number of the first BLOB page */
-	ulint		offset)	/*!< in: offset on the first BLOB page */
+	ulint		offset,	/*!< in: offset on the first BLOB page */
+	trx_t*		trx)	/*!< in: transaction handle */
 {
 	if (UNIV_UNLIKELY(len == 0)) {
 		return(0);
@@ -5656,7 +5659,7 @@ btr_copy_externally_stored_field_prefix_low(
 					     space_id, page_no, offset));
 	} else {
 		return(btr_copy_blob_prefix(buf, len, space_id,
-					    page_no, offset));
+					    page_no, offset, trx));
 	}
 }
 
@@ -5677,7 +5680,8 @@ btr_copy_externally_stored_field_prefix(
 				field containing also the reference to
 				the external part; must be protected by
 				a lock or a page latch */
-	ulint		local_len)/*!< in: length of data, in bytes */
+	ulint		local_len,/*!< in: length of data, in bytes */
+	trx_t*		trx)	/*!< in: transaction handle */
 {
 	ulint	space_id;
 	ulint	page_no;
@@ -5716,7 +5720,7 @@ btr_copy_externally_stored_field_prefix(
 							     len - local_len,
 							     zip_size,
 							     space_id, page_no,
-							     offset));
+							     offset, trx));
 }
 
 /*******************************************************************//**
@@ -5735,7 +5739,8 @@ btr_copy_externally_stored_field(
 	ulint		zip_size,/*!< in: nonzero=compressed BLOB page size,
 				zero for uncompressed BLOBs */
 	ulint		local_len,/*!< in: length of data */
-	mem_heap_t*	heap)	/*!< in: mem heap */
+	mem_heap_t*	heap,	/*!< in: mem heap */
+	trx_t*		trx)	/*!< in: transaction handle */
 {
 	ulint	space_id;
 	ulint	page_no;
@@ -5766,7 +5771,8 @@ btr_copy_externally_stored_field(
 							      extern_len,
 							      zip_size,
 							      space_id,
-							      page_no, offset);
+							      page_no, offset,
+							      trx);
 
 	return(buf);
 }
@@ -5785,7 +5791,8 @@ btr_rec_copy_externally_stored_field(
 				zero for uncompressed BLOBs */
 	ulint		no,	/*!< in: field number */
 	ulint*		len,	/*!< out: length of the field */
-	mem_heap_t*	heap)	/*!< in: mem heap */
+	mem_heap_t*	heap,	/*!< in: mem heap */
+	trx_t*		trx)	/*!< in: transaction handle */
 {
 	ulint		local_len;
 	const byte*	data;
@@ -5816,6 +5823,7 @@ btr_rec_copy_externally_stored_field(
 	}
 
 	return(btr_copy_externally_stored_field(len, data,
-						zip_size, local_len, heap));
+						zip_size, local_len, heap,
+						trx));
 }
 #endif /* !UNIV_HOTBACKUP */

storage/xtradb/btr/btr0pcur.cc

@@ -501,7 +501,7 @@ btr_pcur_move_backward_from_page(
 
 	mtr_commit(mtr);
 
-	mtr_start(mtr);
+	mtr_start_trx(mtr, mtr->trx);
 
 	btr_pcur_restore_position(latch_mode2, cursor, mtr);
 

storage/xtradb/fts/fts0fts.cc

@@ -3393,7 +3393,8 @@ fts_fetch_doc_from_rec(
 					dict_table_zip_size(table),
 					clust_pos, &doc->text.f_len,
 					static_cast<mem_heap_t*>(
-						doc->self_heap->arg));
+						doc->self_heap->arg),
+					NULL);
 		} else {
 			doc->text.f_str = (byte*) rec_get_nth_field(
 				clust_rec, offsets, clust_pos,
@@ -7077,7 +7078,8 @@ fts_init_recover_doc(
 				&doc.text.f_len,
 				static_cast<byte*>(dfield_get_data(dfield)),
 				zip_size, len,
-				static_cast<mem_heap_t*>(doc.self_heap->arg));
+				static_cast<mem_heap_t*>(doc.self_heap->arg),
+				NULL);
 		} else {
 			doc.text.f_str = static_cast<byte*>(
 				dfield_get_data(dfield));

storage/xtradb/fts/fts0que.cc

@@ -1918,7 +1918,8 @@ fts_query_fetch_document(
 		if (dfield_is_ext(dfield)) {
 			data = btr_copy_externally_stored_field(
 				&cur_len, data, phrase->zip_size,
-				dfield_get_len(dfield), phrase->heap);
+				dfield_get_len(dfield), phrase->heap,
+				NULL);
 		} else {
 			cur_len = dfield_get_len(dfield);
 		}

storage/xtradb/handler/ha_innodb.cc

@@ -11512,7 +11512,7 @@ ha_innobase::records_in_range(
 
 		n_rows = btr_estimate_n_rows_in_range(index, range_start,
 						      mode1, range_end,
-						      mode2);
+						      mode2, prebuilt->trx);
 	} else {
 
 		n_rows = HA_POS_ERROR;

storage/xtradb/include/btr0cur.h

@@ -567,7 +567,8 @@ btr_estimate_n_rows_in_range(
 	const dtuple_t*	tuple1,	/*!< in: range start, may also be empty tuple */
 	ulint		mode1,	/*!< in: search mode for range start */
 	const dtuple_t*	tuple2,	/*!< in: range end, may also be empty tuple */
-	ulint		mode2);	/*!< in: search mode for range end */
+	ulint		mode2,	/*!< in: search mode for range end */
+	trx_t*		trx);	/*!< in: trx */
 /*******************************************************************//**
 Estimates the number of different key values in a given index, for
 each n-column prefix of the index where 1 <= n <= dict_index_get_n_unique(index).
@@ -703,7 +704,8 @@ btr_copy_externally_stored_field_prefix(
 				field containing also the reference to
 				the external part; must be protected by
 				a lock or a page latch */
-	ulint		local_len);/*!< in: length of data, in bytes */
+	ulint		local_len,/*!< in: length of data, in bytes */
+	trx_t*		trx);	/*!< in: transaction handle */
 /*******************************************************************//**
 Copies an externally stored field of a record to mem heap.  The
 clustered index record must be protected by a lock or a page latch.
@@ -720,7 +722,8 @@ btr_copy_externally_stored_field(
 	ulint		zip_size,/*!< in: nonzero=compressed BLOB page size,
 				zero for uncompressed BLOBs */
 	ulint		local_len,/*!< in: length of data */
-	mem_heap_t*	heap);	/*!< in: mem heap */
+	mem_heap_t*	heap,	/*!< in: mem heap */
+	trx_t*		trx);	/*!< in: transaction handle */
 /*******************************************************************//**
 Copies an externally stored field of a record to mem heap.
 @return	the field copied to heap, or NULL if the field is incomplete */
@@ -735,7 +738,8 @@ btr_rec_copy_externally_stored_field(
 				zero for uncompressed BLOBs */
 	ulint		no,	/*!< in: field number */
 	ulint*		len,	/*!< out: length of the field */
-	mem_heap_t*	heap);	/*!< in: mem heap */
+	mem_heap_t*	heap,	/*!< in: mem heap */
+	trx_t*		trx);	/*!< in: transaction handle */
 /*******************************************************************//**
 Flags the data tuple fields that are marked as extern storage in the
 update vector.  We use this function to remember which fields we must

storage/xtradb/include/mtr0mtr.h

@@ -35,6 +35,7 @@ Created 11/26/1995 Heikki Tuuri
 #include "ut0byte.h"
 #include "mtr0types.h"
 #include "page0types.h"
+#include "trx0types.h"
 
 /* Logging modes for a mini-transaction */
 #define MTR_LOG_ALL		21	/* default mode: log all operations
@@ -200,6 +201,15 @@ functions).  The page number parameter was originally written as 0. @{ */
 /* included here because it needs MLOG_LSN defined */
 #include "log0log.h"
 
+/***************************************************************//**
+Starts a mini-transaction. */
+UNIV_INLINE
+void
+mtr_start_trx(
+/*======*/
+	mtr_t*	mtr,	/*!< out: mini-transaction */
+	trx_t*	trx)	/*!< in: transaction */
+	__attribute__((nonnull (1)));
 /***************************************************************//**
 Starts a mini-transaction. */
 UNIV_INLINE
@@ -207,7 +217,10 @@ void
 mtr_start(
 /*======*/
 	mtr_t*	mtr)	/*!< out: mini-transaction */
-	__attribute__((nonnull));
+{
+	mtr_start_trx(mtr, NULL);
+}
+	__attribute__((nonnull))
 /***************************************************************//**
 Commits a mini-transaction. */
 UNIV_INTERN
@@ -403,6 +416,7 @@ struct mtr_t{
 #ifdef UNIV_DEBUG
 	ulint		magic_n;
 #endif /* UNIV_DEBUG */
+	trx_t*		trx;	/*!< transaction */
 };
 
 #ifdef UNIV_DEBUG

storage/xtradb/include/mtr0mtr.ic

@@ -43,9 +43,10 @@ mtr_block_dirtied(
 Starts a mini-transaction. */
 UNIV_INLINE
 void
-mtr_start(
+mtr_start_trx(
 /*======*/
-	mtr_t*	mtr)	/*!< out: mini-transaction */
+	mtr_t*	mtr,	/*!< out: mini-transaction */
+	trx_t*	trx)	/*!< in: transaction */
 {
 	UNIV_MEM_INVALID(mtr, sizeof *mtr);
 
@@ -58,6 +59,7 @@ mtr_start(
 	mtr->made_dirty = FALSE;
 	mtr->n_log_recs = 0;
 	mtr->n_freed_pages = 0;
+	mtr->trx = trx;
 
 	ut_d(mtr->state = MTR_ACTIVE);
 	ut_d(mtr->magic_n = MTR_MAGIC_N);

storage/xtradb/include/trx0undo.h

@@ -243,22 +243,13 @@ Truncates an undo log from the end. This function is used during a rollback
 to free space from an undo log. */
 UNIV_INTERN
 void
-trx_undo_truncate_end_func(
+trx_undo_truncate_end(
 /*=======================*/
-#ifdef UNIV_DEBUG
-	const trx_t*	trx,	/*!< in: transaction whose undo log it is */
-#endif /* UNIV_DEBUG */
+	trx_t*		trx,	/*!< in: transaction whose undo log it is */
 	trx_undo_t*	undo,	/*!< in/out: undo log */
 	undo_no_t	limit)	/*!< in: all undo records with undo number
 				>= this value should be truncated */
 	__attribute__((nonnull));
-#ifdef UNIV_DEBUG
-# define trx_undo_truncate_end(trx,undo,limit)		\
-	trx_undo_truncate_end_func(trx,undo,limit)
-#else /* UNIV_DEBUG */
-# define trx_undo_truncate_end(trx,undo,limit)		\
-	trx_undo_truncate_end_func(undo,limit)
-#endif /* UNIV_DEBUG */
 
 /***********************************************************************//**
 Truncates an undo log from the start. This function is used during a purge

storage/xtradb/row/row0ext.cc

@@ -78,7 +78,8 @@ row_ext_cache_fill(
 			crashed during the execution of
 			btr_free_externally_stored_field(). */
 			ext->len[i] = btr_copy_externally_stored_field_prefix(
-				buf, ext->max_len, zip_size, field, f_len);
+				buf, ext->max_len, zip_size, field, f_len,
+				NULL);
 		}
 	}
 }

storage/xtradb/row/row0ftsort.cc

@@ -663,7 +663,8 @@ loop:
 				doc.text.f_str =
 					btr_copy_externally_stored_field(
 						&doc.text.f_len, data,
-						zip_size, data_len, blob_heap);
+						zip_size, data_len, blob_heap,
+						NULL);
 			} else {
 				doc.text.f_str = data;
 				doc.text.f_len = data_len;

storage/xtradb/row/row0ins.cc

@@ -1294,7 +1294,7 @@ row_ins_foreign_check_on_constraint(
 
 	row_mysql_freeze_data_dictionary(thr_get_trx(thr));
 
-	mtr_start(mtr);
+	mtr_start_trx(mtr, trx);
 
 	/* Restore pcur position */
 
@@ -1322,7 +1322,7 @@ nonstandard_exit_func:
 	btr_pcur_store_position(pcur, mtr);
 
 	mtr_commit(mtr);
-	mtr_start(mtr);
+	mtr_start_trx(mtr, trx);
 
 	btr_pcur_restore_position(BTR_SEARCH_LEAF, pcur, mtr);
 
@@ -1530,7 +1530,7 @@ run_again:
 		}
 	}
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	/* Store old value on n_fields_cmp */
 
@@ -2343,7 +2343,7 @@ row_ins_clust_index_entry_low(
 	      || n_uniq == dict_index_get_n_unique(index));
 	ut_ad(!n_uniq || n_uniq == dict_index_get_n_unique(index));
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	if (mode == BTR_MODIFY_LEAF && dict_index_is_online_ddl(index)) {
 		if (UNIV_UNLIKELY(thr_get_trx(thr)->fake_changes)) {
@@ -2571,9 +2571,10 @@ Starts a mini-transaction and checks if the index will be dropped.
 @return true if the index is to be dropped */
 static __attribute__((nonnull, warn_unused_result))
 bool
-row_ins_sec_mtr_start_and_check_if_aborted(
+row_ins_sec_mtr_start_trx_and_check_if_aborted(
 /*=======================================*/
 	mtr_t*		mtr,	/*!< out: mini-transaction */
+	trx_t*		trx,	/*!< in: transaction handle */
 	dict_index_t*	index,	/*!< in/out: secondary index */
 	bool		check,	/*!< in: whether to check */
 	ulint		search_mode)
@@ -2581,7 +2582,7 @@ row_ins_sec_mtr_start_and_check_if_aborted(
 {
 	ut_ad(!dict_index_is_clust(index));
 
-	mtr_start(mtr);
+	mtr_start_trx(mtr, trx);
 
 	if (!check) {
 		return(false);
@@ -2639,13 +2640,14 @@ row_ins_sec_index_entry_low(
 	ulint		n_unique;
 	mtr_t		mtr;
 	ulint*		offsets	= NULL;
+	trx_t*		trx = thr_get_trx(thr);
 
 	ut_ad(!dict_index_is_clust(index));
 	ut_ad(mode == BTR_MODIFY_LEAF || mode == BTR_MODIFY_TREE);
 
 	cursor.thr = thr;
 	ut_ad(thr_get_trx(thr)->id);
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	/* Ensure that we acquire index->lock when inserting into an
 	index with index->online_status == ONLINE_INDEX_COMPLETE, but
@@ -2706,8 +2708,8 @@ row_ins_sec_index_entry_low(
 
 		DEBUG_SYNC_C("row_ins_sec_index_unique");
 
-		if (row_ins_sec_mtr_start_and_check_if_aborted(
-			    &mtr, index, check, search_mode)) {
+		if (row_ins_sec_mtr_start_trx_and_check_if_aborted(
+			    &mtr, trx, index, check, search_mode)) {
 			goto func_exit;
 		}
 
@@ -2741,8 +2743,8 @@ row_ins_sec_index_entry_low(
 			return(err);
 		}
 
-		if (row_ins_sec_mtr_start_and_check_if_aborted(
-			    &mtr, index, check, search_mode)) {
+		if (row_ins_sec_mtr_start_trx_and_check_if_aborted(
+			    &mtr, trx, index, check, search_mode)) {
 			goto func_exit;
 		}
 

storage/xtradb/row/row0log.cc

@@ -981,7 +981,7 @@ row_log_table_get_pk_col(
 			mem_heap_alloc(heap, field_len));
 
 		len = btr_copy_externally_stored_field_prefix(
-			blob_field, field_len, zip_size, field, len);
+			blob_field, field_len, zip_size, field, len, NULL);
 		if (len >= max_len + 1) {
 			return(DB_TOO_BIG_INDEX_COL);
 		}
@@ -1372,7 +1372,7 @@ row_log_table_apply_convert_mrec(
 			data = btr_rec_copy_externally_stored_field(
 				mrec, offsets,
 				dict_table_zip_size(index->table),
-				i, &len, heap);
+				i, &len, heap, NULL);
 			ut_a(data);
 			dfield_set_data(dfield, data, len);
 blob_done:

storage/xtradb/row/row0merge.cc

@@ -2252,7 +2252,7 @@ row_merge_copy_blobs(
 		BLOB pointers are read (row_merge_read_clustered_index())
 		and dereferenced (below). */
 		data = btr_rec_copy_externally_stored_field(
-			mrec, offsets, zip_size, i, &len, heap);
+			mrec, offsets, zip_size, i, &len, heap, NULL);
 		/* Because we have locked the table, any records
 		written by incomplete transactions must have been
 		rolled back already. There must not be any incomplete

storage/xtradb/row/row0mysql.cc

@@ -1859,7 +1859,7 @@ row_unlock_for_mysql(
 		trx_id_t	rec_trx_id;
 		mtr_t		mtr;
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 
 		/* Restore the cursor position and find the record */
 
@@ -3426,7 +3426,7 @@ row_truncate_table_for_mysql(
 				index = dict_table_get_next_index(index);
 			} while (index);
 
-			mtr_start(&mtr);
+			mtr_start_trx(&mtr, trx);
 			fsp_header_init(space,
 					FIL_IBD_FILE_INITIAL_SIZE, &mtr);
 			mtr_commit(&mtr);
@@ -3455,7 +3455,7 @@ row_truncate_table_for_mysql(
 	sys_index = dict_table_get_first_index(dict_sys->sys_indexes);
 	dict_index_copy_types(tuple, sys_index, 1);
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 	btr_pcur_open_on_user_rec(sys_index, tuple, PAGE_CUR_GE,
 				  BTR_MODIFY_LEAF, &pcur, &mtr);
 	for (;;) {
@@ -3502,7 +3502,7 @@ row_truncate_table_for_mysql(
 			a page in this mini-transaction, and the rest of
 			this loop could latch another index page. */
 			mtr_commit(&mtr);
-			mtr_start(&mtr);
+			mtr_start_trx(&mtr, trx);
 			btr_pcur_restore_position(BTR_MODIFY_LEAF,
 						  &pcur, &mtr);
 		}

storage/xtradb/row/row0sel.cc

@@ -133,7 +133,8 @@ row_sel_sec_rec_is_for_blob(
 
 	len = btr_copy_externally_stored_field_prefix(buf, prefix_len,
 						      zip_size,
-						      clust_field, clust_len);
+						      clust_field, clust_len,
+						      NULL);
 
 	if (UNIV_UNLIKELY(len == 0)) {
 		/* The BLOB was being deleted as the server crashed.
@@ -452,7 +453,7 @@ row_sel_fetch_columns(
 				data = btr_rec_copy_externally_stored_field(
 					rec, offsets,
 					dict_table_zip_size(index->table),
-					field_no, &len, heap);
+					field_no, &len, heap, NULL);
 
 				/* data == NULL means that the
 				externally stored field was not
@@ -1400,7 +1401,7 @@ table_loop:
 
 	/* Open a cursor to index, or restore an open cursor position */
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	if (consistent_read && plan->unique_search && !plan->pcur_is_open
 	    && !plan->must_get_clust
@@ -1441,7 +1442,7 @@ table_loop:
 		plan_reset_cursor(plan);
 
 		mtr_commit(&mtr);
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, thr_get_trx(thr));
 	}
 
 	if (search_latch_locked) {
@@ -2815,7 +2816,7 @@ row_sel_store_mysql_field_func(
 		data = btr_rec_copy_externally_stored_field(
 			rec, offsets,
 			dict_table_zip_size(prebuilt->table),
-			field_no, &len, heap);
+			field_no, &len, heap, NULL);
 
 		if (UNIV_UNLIKELY(!data)) {
 			/* The externally stored field was not written
@@ -3882,7 +3883,7 @@ row_search_for_mysql(
 		}
 	}
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	/*-------------------------------------------------------------*/
 	/* PHASE 2: Try fast adaptive hash index search if possible */
@@ -5020,7 +5021,7 @@ next_rec:
 		mtr_commit(&mtr);
 		mtr_has_extra_clust_latch = FALSE;
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 		if (sel_restore_position_for_mysql(&same_user_rec,
 						   BTR_SEARCH_LEAF,
 						   pcur, moves_up, &mtr)) {
@@ -5085,7 +5086,7 @@ lock_table_wait:
 		/* It was a lock wait, and it ended */
 
 		thr->lock_state = QUE_THR_LOCK_NOLOCK;
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 
 		/* Table lock waited, go try to obtain table lock
 		again */

storage/xtradb/row/row0umod.cc

@@ -267,7 +267,7 @@ row_undo_mod_clust(
 	pcur = &node->pcur;
 	index = btr_cur_get_index(btr_pcur_get_btr_cur(pcur));
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	online = dict_index_is_online_ddl(index);
 	if (online) {
@@ -296,7 +296,7 @@ row_undo_mod_clust(
 		/* We may have to modify tree structure: do a pessimistic
 		descent down the index tree */
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, thr_get_trx(thr));
 
 		err = row_undo_mod_clust_low(
 			node, &offsets, &offsets_heap,
@@ -341,7 +341,7 @@ row_undo_mod_clust(
 
 	if (err == DB_SUCCESS && node->rec_type == TRX_UNDO_UPD_DEL_REC) {
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, thr_get_trx(thr));
 
 		/* It is not necessary to call row_log_table,
 		because the record is delete-marked and would thus
@@ -354,7 +354,7 @@ row_undo_mod_clust(
 			/* We may have to modify tree structure: do a
 			pessimistic descent down the index tree */
 
-			mtr_start(&mtr);
+			mtr_start_trx(&mtr, thr_get_trx(thr));
 
 			err = row_undo_mod_remove_clust_low(node, thr, &mtr,
 							    BTR_MODIFY_TREE);
@@ -401,7 +401,7 @@ row_undo_mod_del_mark_or_remove_sec_low(
 	enum row_search_result	search_result;
 
 	log_free_check();
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	if (*index->name == TEMP_INDEX_PREFIX) {
 		/* The index->online_status may change if the
@@ -457,7 +457,7 @@ row_undo_mod_del_mark_or_remove_sec_low(
 	which cannot be purged yet, requires its existence. If some requires,
 	we should delete mark the record. */
 
-	mtr_start(&mtr_vers);
+	mtr_start_trx(&mtr_vers, thr_get_trx(thr));
 
 	success = btr_pcur_restore_position(BTR_SEARCH_LEAF, &(node->pcur),
 					    &mtr_vers);
@@ -573,7 +573,7 @@ row_undo_mod_del_unmark_sec_and_undo_update(
 	ut_ad(trx->id);
 
 	log_free_check();
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	if (*index->name == TEMP_INDEX_PREFIX) {
 		/* The index->online_status may change if the

storage/xtradb/row/row0upd.cc

@@ -212,7 +212,7 @@ row_upd_check_references_constraints(
 
 	DEBUG_SYNC_C("foreign_constraint_check_for_update");
 
-	mtr_start(mtr);
+	mtr_start_trx(mtr, trx);
 
 	if (trx->dict_operation_lock_mode == 0) {
 		got_s_lock = TRUE;
@@ -986,7 +986,7 @@ row_upd_ext_fetch(
 	byte*	buf = static_cast<byte*>(mem_heap_alloc(heap, *len));
 
 	*len = btr_copy_externally_stored_field_prefix(
-		buf, *len, zip_size, data, local_len);
+		buf, *len, zip_size, data, local_len, NULL);
 
 	/* We should never update records containing a half-deleted BLOB. */
 	ut_a(*len);
@@ -1687,7 +1687,7 @@ row_upd_sec_index_entry(
 	}
 #endif /* UNIV_DEBUG */
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	if (*index->name == TEMP_INDEX_PREFIX) {
 		/* The index->online_status may change if the
@@ -2160,7 +2160,7 @@ row_upd_clust_rec(
 	/* We may have to modify the tree structure: do a pessimistic descent
 	down the index tree */
 
-	mtr_start(mtr);
+	mtr_start_trx(mtr, thr_get_trx(thr));
 
 	/* NOTE: this transaction has an s-lock or x-lock on the record and
 	therefore other transactions cannot modify the record when we have no
@@ -2330,7 +2330,7 @@ row_upd_clust_step(
 
 	/* We have to restore the cursor to its position */
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, thr_get_trx(thr));
 
 	/* If the restoration does not succeed, then the same
 	transaction has deleted the record on which the cursor was,
@@ -2386,7 +2386,7 @@ row_upd_clust_step(
 
 		mtr_commit(&mtr);
 
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, thr_get_trx(thr));
 
 		success = btr_pcur_restore_position(BTR_MODIFY_LEAF, pcur,
 						    &mtr);

storage/xtradb/trx/trx0rec.cc

@@ -466,7 +466,7 @@ trx_undo_page_fetch_ext(
 {
 	/* Fetch the BLOB. */
 	ulint	ext_len = btr_copy_externally_stored_field_prefix(
-		ext_buf, prefix_len, zip_size, field, *len);
+		ext_buf, prefix_len, zip_size, field, *len, NULL);
 	/* BLOBs should always be nonempty. */
 	ut_a(ext_len);
 	/* Append the BLOB pointer to the prefix. */
@@ -1247,7 +1247,7 @@ trx_undo_report_row_operation(
 
 	rseg = trx->rseg;
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 	mutex_enter(&trx->undo_mutex);
 
 	/* If the undo log is not assigned yet, assign one */
@@ -1336,7 +1336,7 @@ trx_undo_report_row_operation(
 				latches, such as SYNC_FSP and SYNC_FSP_PAGE. */
 
 				mtr_commit(&mtr);
-				mtr_start(&mtr);
+				mtr_start_trx(&mtr, trx);
 
 				mutex_enter(&rseg->mutex);
 				trx_undo_free_last_page(trx, undo, &mtr);
@@ -1373,7 +1373,7 @@ trx_undo_report_row_operation(
 		/* We have to extend the undo log by one page */
 
 		ut_ad(++loop_count < 2);
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 
 		/* When we add a page to an undo log, this is analogous to
 		a pessimistic insert in a B-tree, and we must reserve the

storage/xtradb/trx/trx0undo.cc

@@ -1067,11 +1067,9 @@ Truncates an undo log from the end. This function is used during a rollback
 to free space from an undo log. */
 UNIV_INTERN
 void
-trx_undo_truncate_end_func(
+trx_undo_truncate_end(
 /*=======================*/
-#ifdef UNIV_DEBUG
-	const trx_t*	trx,	/*!< in: transaction whose undo log it is */
-#endif /* UNIV_DEBUG */
+	trx_t*		trx,	/*!< in: transaction whose undo log it is */
 	trx_undo_t*	undo,	/*!< in: undo log */
 	undo_no_t	limit)	/*!< in: all undo records with undo number
 				>= this value should be truncated */
@@ -1086,7 +1084,7 @@ trx_undo_truncate_end_func(
 	ut_ad(mutex_own(&(trx->rseg->mutex)));
 
 	for (;;) {
-		mtr_start(&mtr);
+		mtr_start_trx(&mtr, trx);
 
 		trunc_here = NULL;
 
@@ -1773,7 +1771,7 @@ trx_undo_assign_undo(
 
 	ut_ad(mutex_own(&(trx->undo_mutex)));
 
-	mtr_start(&mtr);
+	mtr_start_trx(&mtr, trx);
 
 	mutex_enter(&rseg->mutex);