MDEV-6928: Add trx pointer to struct mtr_t

Merge Facebook commit 25295d003cb0c17aa8fb756523923c77250b3294
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.

1 files changed, 15 insertions, 1 deletions

diff --git a/storage/xtradb/include/mtr0mtr.h b/storage/xtradb/include/mtr0mtr.h
index 0730e870b3f..827039953be 100644
--- a/storage/xtradb/include/mtr0mtr.h
+++ b/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
@@ -204,10 +205,22 @@ functions).  The page number parameter was originally written as 0. @{ */
 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
+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