Reduce the amount of time(NULL) calls for lock processing

lock_t::requested_time: Document what the field is used for.

lock_t::wait_time: Document that the field is only used for
diagnostics and may be garbage if the system time is being adjusted.

srv_slot_t::suspend_time: Document that this is duplicating
trx_lock_t::wait_started.

lock_table_print(), lock_rec_print(): Declare in static scope.
Add a parameter for the current time.

lock_deadlock_check_and_resolve(), lock_deadlock_lock_print(),
lock_deadlock_joining_trx_print():
Add a parameter for the current time.

storage/innobase/include/lock0lock.h

@@ -615,22 +615,6 @@ lock_report_trx_id_insanity(
 	trx_id_t	max_trx_id)	/*!< in: trx_sys_get_max_trx_id() */
 	MY_ATTRIBUTE((nonnull));
 /*********************************************************************//**
-Prints info of a table lock. */
-UNIV_INTERN
-void
-lock_table_print(
-/*=============*/
-	FILE*		file,	/*!< in: file where to print */
-	const lock_t*	lock);	/*!< in: table type lock */
-/*********************************************************************//**
-Prints info of a record lock. */
-UNIV_INTERN
-void
-lock_rec_print(
-/*===========*/
-	FILE*		file,	/*!< in: file where to print */
-	const lock_t*	lock);	/*!< in: record type lock */
-/*********************************************************************//**
 Prints info of locks for all transactions.
 @return FALSE if not able to obtain lock mutex and exits without
 printing info */

storage/innobase/include/lock0priv.h

@@ -74,10 +74,14 @@ struct lock_t {
 					lock */
 	dict_index_t*	index;		/*!< index for a record lock */
 
-	/* Statistics for how long lock has been held and time
-	how long this lock had to be waited before it was granted */
-	time_t		requested_time; /*!< Lock request time */
-	ulint		wait_time;	/*!< Time waited this lock or 0 */
+	/** time(NULL) of the lock request creation.
+	Used for computing wait_time and diagnostics only.
+	Note: bogus durations may be reported
+	when the system time is adjusted! */
+	time_t		requested_time;
+	/** Cumulated wait time in seconds.
+	Note: may be bogus when the system time is adjusted! */
+	ulint		wait_time;
 
 	union {
 		lock_table_t	tab_lock;/*!< table lock */

storage/innobase/include/srv0srv.h

@@ -1078,10 +1078,14 @@ struct srv_slot_t{
 	ibool		suspended;		/*!< TRUE if the thread is
 						waiting for the event of this
 						slot */
-	ib_time_t	suspend_time;		/*!< time when the thread was
-						suspended. Initialized by
-						lock_wait_table_reserve_slot()
-						for lock wait */
+ 	/** time(NULL) when the thread was suspended.
+ 	FIXME: Use my_interval_timer() or similar, to avoid bogus
+ 	timeouts in lock_wait_check_and_cancel() or lock_wait_suspend_thread()
+	when the system time is adjusted to the past!
+
+	FIXME: This is duplicating trx_lock_t::wait_started,
+	which is being used for diagnostic purposes only. */
+	time_t		suspend_time;
 	ulong		wait_timeout;		/*!< wait time that if exceeded
 						the thread will be timed out.
 						Initialized by

storage/innobase/include/trx0i_s.h

 /*****************************************************************************
 
 Copyright (c) 2007, 2011, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2019, 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
@@ -133,7 +134,7 @@ struct i_s_trx_row_t {
 					/*!< pointer to a row
 					in innodb_locks if trx
 					is waiting, or NULL */
-	ib_time_t	trx_wait_started; /*!< trx_t::wait_started */
+	time_t		trx_wait_started; /*!< trx->lock.wait_started */
 	ullint		trx_weight;	/*!< TRX_WEIGHT() */
 	ulint		trx_mysql_thread_id; /*!< thd_get_thread_id() */
 	const char*	trx_query;	/*!< MySQL statement being

storage/innobase/lock/lock0wait.cc

@@ -226,7 +226,6 @@ lock_wait_suspend_thread(
 				user OS thread */
 {
 	srv_slot_t*	slot;
-	double		wait_time;
 	trx_t*		trx;
 	ulint		had_dict_lock;
 	ibool		was_declared_inside_innodb;
@@ -360,7 +359,7 @@ lock_wait_suspend_thread(
 		row_mysql_freeze_data_dictionary(trx);
 	}
 
-	wait_time = ut_difftime(ut_time(), slot->suspend_time);
+	double wait_time = difftime(time(NULL), slot->suspend_time);
 
 	/* Release the slot for others to use */
 
@@ -451,19 +450,12 @@ lock_wait_check_and_cancel(
 	const srv_slot_t*	slot)	/*!< in: slot reserved by a user
 					thread when the wait started */
 {
-	trx_t*		trx;
-	double		wait_time;
-	ib_time_t	suspend_time = slot->suspend_time;
-
 	ut_ad(lock_wait_mutex_own());
-
 	ut_ad(slot->in_use);
-
 	ut_ad(slot->suspended);
 
-	wait_time = ut_difftime(ut_time(), suspend_time);
-
-	trx = thr_get_trx(slot->thr);
+	double wait_time = difftime(time(NULL), slot->suspend_time);
+	trx_t* trx = thr_get_trx(slot->thr);
 
 	if (trx_is_interrupted(trx)
 	    || (slot->wait_timeout < 100000000
@@ -497,7 +489,6 @@ lock_wait_check_and_cancel(
 
 		trx_mutex_exit(trx);
 	}
-
 }
 
 /*********************************************************************//**

storage/xtradb/include/lock0lock.h

@@ -629,22 +629,6 @@ lock_report_trx_id_insanity(
 	trx_id_t	max_trx_id)	/*!< in: trx_sys_get_max_trx_id() */
 	MY_ATTRIBUTE((nonnull));
 /*********************************************************************//**
-Prints info of a table lock. */
-UNIV_INTERN
-void
-lock_table_print(
-/*=============*/
-	FILE*		file,	/*!< in: file where to print */
-	const lock_t*	lock);	/*!< in: table type lock */
-/*********************************************************************//**
-Prints info of a record lock. */
-UNIV_INTERN
-void
-lock_rec_print(
-/*===========*/
-	FILE*		file,	/*!< in: file where to print */
-	const lock_t*	lock);	/*!< in: record type lock */
-/*********************************************************************//**
 Prints info of locks for all transactions.
 @return FALSE if not able to obtain lock mutex and exits without
 printing info */

storage/xtradb/include/lock0priv.h

@@ -74,10 +74,14 @@ struct lock_t {
 					lock */
 	dict_index_t*	index;		/*!< index for a record lock */
 
-	/* Statistics for how long lock has been held and time
-	how long this lock had to be waited before it was granted */
-	time_t		requested_time; /*!< Lock request time */
-	ulint		wait_time;	/*!< Time waited this lock or 0 */
+	/** time(NULL) of the lock request creation.
+	Used for computing wait_time and diagnostics only.
+	Note: bogus durations may be reported
+	when the system time is adjusted! */
+	time_t		requested_time;
+	/** Cumulated wait time in seconds.
+	Note: may be bogus when the system time is adjusted! */
+	ulint		wait_time;
 
 	union {
 		lock_table_t	tab_lock;/*!< table lock */

storage/xtradb/include/srv0srv.h

@@ -1332,7 +1332,10 @@ struct srv_slot_t{
 	/** time(NULL) when the thread was suspended.
 	FIXME: Use my_interval_timer() or similar, to avoid bogus
 	timeouts in lock_wait_check_and_cancel() or lock_wait_suspend_thread()
-	when the system time is adjusted to the past! */
+	when the system time is adjusted to the past!
+
+	FIXME: This is duplicating trx_lock_t::wait_started,
+	which is being used for diagnostic purposes only. */
 	time_t		suspend_time;
 	ulong		wait_timeout;		/*!< wait time that if exceeded
 						the thread will be timed out.

storage/xtradb/include/trx0i_s.h

 /*****************************************************************************
 
 Copyright (c) 2007, 2011, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2019, 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
@@ -133,7 +134,7 @@ struct i_s_trx_row_t {
 					/*!< pointer to a row
 					in innodb_locks if trx
 					is waiting, or NULL */
-	ib_time_t	trx_wait_started; /*!< trx_t::wait_started */
+	time_t		trx_wait_started; /*!< trx->lock.wait_started */
 	ullint		trx_weight;	/*!< TRX_WEIGHT() */
 	ulint		trx_mysql_thread_id; /*!< thd_get_thread_id() */
 	const char*	trx_query;	/*!< MySQL statement being

storage/xtradb/lock/lock0wait.cc

@@ -280,7 +280,6 @@ lock_wait_suspend_thread(
 				user OS thread */
 {
 	srv_slot_t*	slot;
-	double		wait_time;
 	trx_t*		trx;
 	ulint		had_dict_lock;
 	ibool		was_declared_inside_innodb;
@@ -416,7 +415,7 @@ lock_wait_suspend_thread(
 		row_mysql_freeze_data_dictionary(trx);
 	}
 
-	wait_time = ut_difftime(ut_time(), slot->suspend_time);
+	double wait_time = difftime(time(NULL), slot->suspend_time);
 
 	/* Release the slot for others to use */
 
@@ -509,19 +508,12 @@ lock_wait_check_and_cancel(
 	const srv_slot_t*	slot)	/*!< in: slot reserved by a user
 					thread when the wait started */
 {
-	trx_t*		trx;
-	double		wait_time;
-	ib_time_t	suspend_time = slot->suspend_time;
-
 	ut_ad(lock_wait_mutex_own());
-
 	ut_ad(slot->in_use);
-
 	ut_ad(slot->suspended);
 
-	wait_time = ut_difftime(ut_time(), suspend_time);
-
-	trx = thr_get_trx(slot->thr);
+	double wait_time = difftime(time(NULL), slot->suspend_time);
+	trx_t* trx = thr_get_trx(slot->thr);
 
 	if (trx_is_interrupted(trx)
 	    || (slot->wait_timeout < 100000000
@@ -555,7 +547,6 @@ lock_wait_check_and_cancel(
 
 		trx_mutex_exit(trx);
 	}
-
 }
 
 /*********************************************************************//**