Merge from mysql-5.1-innodb:

------------------------------------------------------------
revno: 3495
committer: Marko Mäkelä <marko.makela@oracle.com>
branch nick: 5.1-innodb
timestamp: Wed 2010-06-02 13:37:14 +0300
message:
  Bug#53674: InnoDB: Error: unlock row could not find a 4 mode lock on the record

  In semi-consistent read, only unlock freshly locked non-matching records.

  lock_rec_lock_fast(): Return LOCK_REC_SUCCESS,
  LOCK_REC_SUCCESS_CREATED, or LOCK_REC_FAIL instead of TRUE/FALSE.

  enum db_err: Add DB_SUCCESS_LOCKED_REC for indicating a successful
  operation where a record lock was created.

  lock_sec_rec_read_check_and_lock(),
  lock_clust_rec_read_check_and_lock(), lock_rec_enqueue_waiting(),
  lock_rec_lock_slow(), lock_rec_lock(), row_ins_set_shared_rec_lock(),
  row_ins_set_exclusive_rec_lock(), sel_set_rec_lock(),
  row_sel_get_clust_rec_for_mysql(): Return DB_SUCCESS_LOCKED_REC if a
  new record lock was created. Adjust callers.

  row_unlock_for_mysql(): Correct the function documentation.

  row_prebuilt_t::new_rec_locks: Correct the documentation.

1 files changed, 85 insertions, 47 deletions

diff --git a/storage/innobase/row/row0sel.c b/storage/innobase/row/row0sel.c
index 4d19ed93a49..a5bf361661b 100644
--- a/storage/innobase/row/row0sel.c
+++ b/storage/innobase/row/row0sel.c
@@ -863,8 +863,14 @@ row_sel_get_clust_rec(
 			clust_rec, index, offsets,
 			node->row_lock_mode, lock_type, thr);
 
-		if (err != DB_SUCCESS) {
-
+		switch (err) {
+		case DB_SUCCESS:
+		case DB_SUCCESS_LOCKED_REC:
+			/* Declare the variable uninitialized in Valgrind.
+			It should be set to DB_SUCCESS at func_exit. */
+			UNIV_MEM_INVALID(&err, sizeof err);
+			break;
+		default:
 			goto err_exit;
 		}
 	} else {
@@ -934,9 +940,9 @@ err_exit:
 
 /*********************************************************************//**
 Sets a lock on a record.
-@return	DB_SUCCESS or error code */
+@return	DB_SUCCESS, DB_SUCCESS_LOCKED_REC, or error code */
 UNIV_INLINE
-ulint
+enum db_err
 sel_set_rec_lock(
 /*=============*/
 	const buf_block_t*	block,	/*!< in: buffer block of rec */
@@ -948,8 +954,8 @@ sel_set_rec_lock(
 					LOC_REC_NOT_GAP */
 	que_thr_t*		thr)	/*!< in: query thread */
 {
-	trx_t*	trx;
-	ulint	err;
+	trx_t*		trx;
+	enum db_err	err;
 
 	trx = thr_get_trx(thr);
 
@@ -1482,11 +1488,15 @@ rec_loop:
 					       node->row_lock_mode,
 					       lock_type, thr);
 
-			if (err != DB_SUCCESS) {
+			switch (err) {
+			case DB_SUCCESS_LOCKED_REC:
+				err = DB_SUCCESS;
+			case DB_SUCCESS:
+				break;
+			default:
 				/* Note that in this case we will store in pcur
 				the PREDECESSOR of the record we are waiting
 				the lock for */
-
 				goto lock_wait_or_error;
 			}
 		}
@@ -1538,8 +1548,12 @@ skip_lock:
 				       rec, index, offsets,
 				       node->row_lock_mode, lock_type, thr);
 
-		if (err != DB_SUCCESS) {
-
+		switch (err) {
+		case DB_SUCCESS_LOCKED_REC:
+			err = DB_SUCCESS;
+		case DB_SUCCESS:
+			break;
+		default:
 			goto lock_wait_or_error;
 		}
 	}
@@ -2801,9 +2815,9 @@ row_sel_build_prev_vers_for_mysql(
 Retrieves the clustered index record corresponding to a record in a
 non-clustered index. Does the necessary locking. Used in the MySQL
 interface.
-@return	DB_SUCCESS or error code */
+@return	DB_SUCCESS, DB_SUCCESS_LOCKED_REC, or error code */
 static
-ulint
+enum db_err
 row_sel_get_clust_rec_for_mysql(
 /*============================*/
 	row_prebuilt_t*	prebuilt,/*!< in: prebuilt struct in the handle */
@@ -2830,7 +2844,7 @@ row_sel_get_clust_rec_for_mysql(
 	dict_index_t*	clust_index;
 	const rec_t*	clust_rec;
 	rec_t*		old_vers;
-	ulint		err;
+	enum db_err	err;
 	trx_t*		trx;
 
 	*out_rec = NULL;
@@ -2889,6 +2903,7 @@ row_sel_get_clust_rec_for_mysql(
 
 		clust_rec = NULL;
 
+		err = DB_SUCCESS;
 		goto func_exit;
 	}
 
@@ -2904,8 +2919,11 @@ row_sel_get_clust_rec_for_mysql(
 			0, btr_pcur_get_block(prebuilt->clust_pcur),
 			clust_rec, clust_index, *offsets,
 			prebuilt->select_lock_type, LOCK_REC_NOT_GAP, thr);
-		if (err != DB_SUCCESS) {
-
+		switch (err) {
+		case DB_SUCCESS:
+		case DB_SUCCESS_LOCKED_REC:
+			break;
+		default:
 			goto err_exit;
 		}
 	} else {
@@ -2965,6 +2983,8 @@ row_sel_get_clust_rec_for_mysql(
 				     rec, sec_index, clust_rec, clust_index));
 #endif
 		}
+
+		err = DB_SUCCESS;
 	}
 
 func_exit:
@@ -2977,7 +2997,6 @@ func_exit:
 		btr_pcur_store_position(prebuilt->clust_pcur, mtr);
 	}
 
-	err = DB_SUCCESS;
 err_exit:
 	return(err);
 }
@@ -3702,8 +3721,12 @@ shortcut_fails_too_big_rec:
 					       prebuilt->select_lock_type,
 					       LOCK_GAP, thr);
 
-			if (err != DB_SUCCESS) {
-
+			switch (err) {
+			case DB_SUCCESS_LOCKED_REC:
+				err = DB_SUCCESS;
+			case DB_SUCCESS:
+				break;
+			default:
 				goto lock_wait_or_error;
 			}
 		}
@@ -3801,8 +3824,12 @@ rec_loop:
 					       prebuilt->select_lock_type,
 					       LOCK_ORDINARY, thr);
 
-			if (err != DB_SUCCESS) {
-
+			switch (err) {
+			case DB_SUCCESS_LOCKED_REC:
+				err = DB_SUCCESS;
+			case DB_SUCCESS:
+				break;
+			default:
 				goto lock_wait_or_error;
 			}
 		}
@@ -3932,8 +3959,11 @@ wrong_offs:
 					prebuilt->select_lock_type, LOCK_GAP,
 					thr);
 
-				if (err != DB_SUCCESS) {
-
+				switch (err) {
+				case DB_SUCCESS_LOCKED_REC:
+				case DB_SUCCESS:
+					break;
+				default:
 					goto lock_wait_or_error;
 				}
 			}
@@ -3968,8 +3998,11 @@ wrong_offs:
 					prebuilt->select_lock_type, LOCK_GAP,
 					thr);
 
-				if (err != DB_SUCCESS) {
-
+				switch (err) {
+				case DB_SUCCESS_LOCKED_REC:
+				case DB_SUCCESS:
+					break;
+				default:
 					goto lock_wait_or_error;
 				}
 			}
@@ -4039,15 +4072,21 @@ no_gap_lock:
 
 		switch (err) {
 			const rec_t*	old_vers;
-		case DB_SUCCESS:
+		case DB_SUCCESS_LOCKED_REC:
 			if (srv_locks_unsafe_for_binlog
-			    || trx->isolation_level <= TRX_ISO_READ_COMMITTED) {
+			    || trx->isolation_level
+			    <= TRX_ISO_READ_COMMITTED) {
 				/* Note that a record of
 				prebuilt->index was locked. */
 				prebuilt->new_rec_locks = 1;
 			}
+			err = DB_SUCCESS;
+		case DB_SUCCESS:
 			break;
 		case DB_LOCK_WAIT:
+			/* Never unlock rows that were part of a conflict. */
+			prebuilt->new_rec_locks = 0;
+
 			if (UNIV_LIKELY(prebuilt->row_read_type
 					!= ROW_READ_TRY_SEMI_CONSISTENT)
 			    || unique_search
@@ -4077,7 +4116,6 @@ no_gap_lock:
 			if (UNIV_LIKELY(trx->wait_lock != NULL)) {
 				lock_cancel_waiting_and_release(
 					trx->wait_lock);
-				prebuilt->new_rec_locks = 0;
 			} else {
 				mutex_exit(&kernel_mutex);
 
@@ -4089,9 +4127,6 @@ no_gap_lock:
 							  ULINT_UNDEFINED,
 							  &heap);
 				err = DB_SUCCESS;
-				/* Note that a record of
-				prebuilt->index was locked. */
-				prebuilt->new_rec_locks = 1;
 				break;
 			}
 			mutex_exit(&kernel_mutex);
@@ -4228,27 +4263,30 @@ requires_clust_rec:
 		err = row_sel_get_clust_rec_for_mysql(prebuilt, index, rec,
 						      thr, &clust_rec,
 						      &offsets, &heap, &mtr);
-		if (err != DB_SUCCESS) {
+		switch (err) {
+		case DB_SUCCESS:
+			if (clust_rec == NULL) {
+				/* The record did not exist in the read view */
+				ut_ad(prebuilt->select_lock_type == LOCK_NONE);
 
+				goto next_rec;
+			}
+			break;
+		case DB_SUCCESS_LOCKED_REC:
+			ut_a(clust_rec != NULL);
+			if (srv_locks_unsafe_for_binlog
+			     || trx->isolation_level
+			    <= TRX_ISO_READ_COMMITTED) {
+				/* Note that the clustered index record
+				was locked. */
+				prebuilt->new_rec_locks = 2;
+			}
+			err = DB_SUCCESS;
+			break;
+		default:
 			goto lock_wait_or_error;
 		}
 
-		if (clust_rec == NULL) {
-			/* The record did not exist in the read view */
-			ut_ad(prebuilt->select_lock_type == LOCK_NONE);
-
-			goto next_rec;
-		}
-
-		if ((srv_locks_unsafe_for_binlog
-		     || trx->isolation_level <= TRX_ISO_READ_COMMITTED)
-		    && prebuilt->select_lock_type != LOCK_NONE) {
-			/* Note that both the secondary index record
-			and the clustered index record were locked. */
-			ut_ad(prebuilt->new_rec_locks == 1);
-			prebuilt->new_rec_locks = 2;
-		}
-
 		if (UNIV_UNLIKELY(rec_get_deleted_flag(clust_rec, comp))) {
 
 			/* The record is delete marked: we can skip it */