MDEV-16136: Simplify trx_lock_t memory management

Allocate trx->lock.rec_pool and trx->lock.table_pool directly from trx_t.
Remove unnecessary use of std::vector.

In order to do this, move some definitions from lock0priv.h to
lock0types.h, so that ib_lock_t will not be an opaque type.

6 files changed, 216 insertions, 275 deletions

diff --git a/storage/innobase/include/lock0lock.h b/storage/innobase/include/lock0lock.h
index c9500f7fd49..f7d507813e3 100644
--- a/storage/innobase/include/lock0lock.h
+++ b/storage/innobase/include/lock0lock.h
@@ -834,69 +834,6 @@ lock_trx_has_rec_x_lock(
 	MY_ATTRIBUTE((warn_unused_result));
 #endif /* UNIV_DEBUG */
 
-/**
-Allocate cached locks for the transaction.
-@param trx		allocate cached record locks for this transaction */
-void
-lock_trx_alloc_locks(trx_t* trx);
-
-/** Lock modes and types */
-/* @{ */
-#define LOCK_MODE_MASK	0xFUL	/*!< mask used to extract mode from the
-				type_mode field in a lock */
-/** Lock types */
-/* @{ */
-#define LOCK_TABLE	16U	/*!< table lock */
-#define	LOCK_REC	32U	/*!< record lock */
-#define LOCK_TYPE_MASK	0xF0UL	/*!< mask used to extract lock type from the
-				type_mode field in a lock */
-#if LOCK_MODE_MASK & LOCK_TYPE_MASK
-# error "LOCK_MODE_MASK & LOCK_TYPE_MASK"
-#endif
-
-#define LOCK_WAIT	256U	/*!< Waiting lock flag; when set, it
-				means that the lock has not yet been
-				granted, it is just waiting for its
-				turn in the wait queue */
-/* Precise modes */
-#define LOCK_ORDINARY	0	/*!< this flag denotes an ordinary
-				next-key lock in contrast to LOCK_GAP
-				or LOCK_REC_NOT_GAP */
-#define LOCK_GAP	512U	/*!< when this bit is set, it means that the
-				lock holds only on the gap before the record;
-				for instance, an x-lock on the gap does not
-				give permission to modify the record on which
-				the bit is set; locks of this type are created
-				when records are removed from the index chain
-				of records */
-#define LOCK_REC_NOT_GAP 1024U	/*!< this bit means that the lock is only on
-				the index record and does NOT block inserts
-				to the gap before the index record; this is
-				used in the case when we retrieve a record
-				with a unique key, and is also used in
-				locking plain SELECTs (not part of UPDATE
-				or DELETE) when the user has set the READ
-				COMMITTED isolation level */
-#define LOCK_INSERT_INTENTION 2048U/*!< this bit is set when we place a waiting
-				gap type record lock request in order to let
-				an insert of an index record to wait until
-				there are no conflicting locks by other
-				transactions on the gap; note that this flag
-				remains set when the waiting lock is granted,
-				or if the lock is inherited to a neighboring
-				record */
-#define LOCK_PREDICATE	8192U	/*!< Predicate lock */
-#define LOCK_PRDT_PAGE	16384U	/*!< Page lock */
-
-
-#if (LOCK_WAIT|LOCK_GAP|LOCK_REC_NOT_GAP|LOCK_INSERT_INTENTION|LOCK_PREDICATE|LOCK_PRDT_PAGE)&LOCK_MODE_MASK
-# error
-#endif
-#if (LOCK_WAIT|LOCK_GAP|LOCK_REC_NOT_GAP|LOCK_INSERT_INTENTION|LOCK_PREDICATE|LOCK_PRDT_PAGE)&LOCK_TYPE_MASK
-# error
-#endif
-/* @} */
-
 /** Lock operation struct */
 struct lock_op_t{
 	dict_table_t*	table;	/*!< table to be locked */
diff --git a/storage/innobase/include/lock0priv.h b/storage/innobase/include/lock0priv.h
index 1c297a5b945..d9377e97d40 100644
--- a/storage/innobase/include/lock0priv.h
+++ b/storage/innobase/include/lock0priv.h
@@ -42,19 +42,6 @@ those functions in lock/ */
 #define UINT32_MAX             (4294967295U)
 #endif
 
-/** A table lock */
-struct lock_table_t {
-	dict_table_t*	table;		/*!< database table in dictionary
-					cache */
-	UT_LIST_NODE_T(lock_t)
-			locks;		/*!< list of locks on the same
-					table */
-	/** Print the table lock into the given output stream
-	@param[in,out]	out	the output stream
-	@return the given output stream. */
-	std::ostream& print(std::ostream& out) const;
-};
-
 /** Print the table lock into the given output stream
 @param[in,out]	out	the output stream
 @return the given output stream. */
@@ -77,131 +64,11 @@ operator<<(std::ostream& out, const lock_table_t& lock)
 	return(lock.print(out));
 }
 
-/** Record lock for a page */
-struct lock_rec_t {
-	ib_uint32_t	space;		/*!< space id */
-	ib_uint32_t	page_no;	/*!< page number */
-	ib_uint32_t	n_bits;		/*!< number of bits in the lock
-					bitmap; NOTE: the lock bitmap is
-					placed immediately after the
-					lock struct */
-
-	/** Print the record lock into the given output stream
-	@param[in,out]	out	the output stream
-	@return the given output stream. */
-	std::ostream& print(std::ostream& out) const;
-};
-
-/** Print the record lock into the given output stream
-@param[in,out]	out	the output stream
-@return the given output stream. */
-inline
-std::ostream& lock_rec_t::print(std::ostream& out) const
-{
-	out << "[lock_rec_t: space=" << space << ", page_no=" << page_no
-		<< ", n_bits=" << n_bits << "]";
-	return(out);
-}
-
-inline
-std::ostream&
-operator<<(std::ostream& out, const lock_rec_t& lock)
-{
-	return(lock.print(out));
-}
-
-/** Lock struct; protected by lock_sys->mutex */
-struct lock_t {
-	trx_t*		trx;		/*!< transaction owning the
-					lock */
-	UT_LIST_NODE_T(lock_t)
-			trx_locks;	/*!< list of the locks of the
-					transaction */
-
-	dict_index_t*	index;		/*!< index for a record lock */
-
-	lock_t*		hash;		/*!< hash chain node for a record
-					lock. The link node in a singly linked
-					list, used during hashing. */
-
-	/* 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 */
-
-	union {
-		lock_table_t	tab_lock;/*!< table lock */
-		lock_rec_t	rec_lock;/*!< record lock */
-	} un_member;			/*!< lock details */
-
-	ib_uint32_t	type_mode;	/*!< lock type, mode, LOCK_GAP or
-					LOCK_REC_NOT_GAP,
-					LOCK_INSERT_INTENTION,
-					wait flag, ORed */
-
-	/** Determine if the lock object is a record lock.
-	@return true if record lock, false otherwise. */
-	bool is_record_lock() const
-	{
-		return(type() == LOCK_REC);
-	}
-
-	bool is_waiting() const
-	{
-		return(type_mode & LOCK_WAIT);
-	}
-
-	bool is_gap() const
-	{
-		return(type_mode & LOCK_GAP);
-	}
-
-	bool is_record_not_gap() const
-	{
-		return(type_mode & LOCK_REC_NOT_GAP);
-	}
-
-	bool is_insert_intention() const
-	{
-		return(type_mode & LOCK_INSERT_INTENTION);
-	}
-
-	ulint type() const {
-		return(type_mode & LOCK_TYPE_MASK);
-	}
-
-	enum lock_mode mode() const
-	{
-		return(static_cast<enum lock_mode>(type_mode & LOCK_MODE_MASK));
-	}
-
-	/** Print the lock object into the given output stream.
-	@param[in,out]	out	the output stream
-	@return the given output stream. */
-	std::ostream& print(std::ostream& out) const;
-
-	/** Convert the member 'type_mode' into a human readable string.
-	@return human readable string */
-	std::string type_mode_string() const;
-
-	const char* type_string() const
-	{
-		switch (type_mode & LOCK_TYPE_MASK) {
-		case LOCK_REC:
-			return("LOCK_REC");
-		case LOCK_TABLE:
-			return("LOCK_TABLE");
-		default:
-			ut_error;
-		}
-	}
-};
-
 /** Convert the member 'type_mode' into a human readable string.
 @return human readable string */
 inline
 std::string
-lock_t::type_mode_string() const
+ib_lock_t::type_mode_string() const
 {
 	std::ostringstream sout;
 	sout << type_string();
@@ -227,7 +94,7 @@ lock_t::type_mode_string() const
 
 inline
 std::ostream&
-lock_t::print(std::ostream& out) const
+ib_lock_t::print(std::ostream& out) const
 {
 	out << "[lock_t: type_mode=" << type_mode << "("
 		<< type_mode_string() << ")";
@@ -244,7 +111,7 @@ lock_t::print(std::ostream& out) const
 
 inline
 std::ostream&
-operator<<(std::ostream& out, const lock_t& lock)
+operator<<(std::ostream& out, const ib_lock_t& lock)
 {
 	return(lock.print(out));
 }
diff --git a/storage/innobase/include/lock0types.h b/storage/innobase/include/lock0types.h
index d08eaabfb1e..1a03d1d0297 100644
--- a/storage/innobase/include/lock0types.h
+++ b/storage/innobase/include/lock0types.h
@@ -1,6 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1996, 2015, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 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
@@ -73,6 +74,195 @@ const char* lock_mode_string(enum lock_mode mode)
 	}
 }
 
-typedef UT_LIST_BASE_NODE_T(lock_t) trx_lock_list_t;
+/** A table lock */
+struct lock_table_t {
+	dict_table_t*	table;		/*!< database table in dictionary
+					cache */
+	UT_LIST_NODE_T(ib_lock_t)
+			locks;		/*!< list of locks on the same
+					table */
+	/** Print the table lock into the given output stream
+	@param[in,out]	out	the output stream
+	@return the given output stream. */
+	std::ostream& print(std::ostream& out) const;
+};
+
+/** Record lock for a page */
+struct lock_rec_t {
+	ib_uint32_t	space;		/*!< space id */
+	ib_uint32_t	page_no;	/*!< page number */
+	ib_uint32_t	n_bits;		/*!< number of bits in the lock
+					bitmap; NOTE: the lock bitmap is
+					placed immediately after the
+					lock struct */
+
+	/** Print the record lock into the given output stream
+	@param[in,out]	out	the output stream
+	@return the given output stream. */
+	std::ostream& print(std::ostream& out) const;
+};
+
+/** Print the record lock into the given output stream
+@param[in,out]	out	the output stream
+@return the given output stream. */
+inline
+std::ostream& lock_rec_t::print(std::ostream& out) const
+{
+	out << "[lock_rec_t: space=" << space << ", page_no=" << page_no
+		<< ", n_bits=" << n_bits << "]";
+	return(out);
+}
+
+inline
+std::ostream&
+operator<<(std::ostream& out, const lock_rec_t& lock)
+{
+	return(lock.print(out));
+}
+
+#define LOCK_MODE_MASK	0xFUL	/*!< mask used to extract mode from the
+				type_mode field in a lock */
+/** Lock types */
+/* @{ */
+#define LOCK_TABLE	16U	/*!< table lock */
+#define	LOCK_REC	32U	/*!< record lock */
+#define LOCK_TYPE_MASK	0xF0UL	/*!< mask used to extract lock type from the
+				type_mode field in a lock */
+#if LOCK_MODE_MASK & LOCK_TYPE_MASK
+# error "LOCK_MODE_MASK & LOCK_TYPE_MASK"
+#endif
+
+#define LOCK_WAIT	256U	/*!< Waiting lock flag; when set, it
+				means that the lock has not yet been
+				granted, it is just waiting for its
+				turn in the wait queue */
+/* Precise modes */
+#define LOCK_ORDINARY	0	/*!< this flag denotes an ordinary
+				next-key lock in contrast to LOCK_GAP
+				or LOCK_REC_NOT_GAP */
+#define LOCK_GAP	512U	/*!< when this bit is set, it means that the
+				lock holds only on the gap before the record;
+				for instance, an x-lock on the gap does not
+				give permission to modify the record on which
+				the bit is set; locks of this type are created
+				when records are removed from the index chain
+				of records */
+#define LOCK_REC_NOT_GAP 1024U	/*!< this bit means that the lock is only on
+				the index record and does NOT block inserts
+				to the gap before the index record; this is
+				used in the case when we retrieve a record
+				with a unique key, and is also used in
+				locking plain SELECTs (not part of UPDATE
+				or DELETE) when the user has set the READ
+				COMMITTED isolation level */
+#define LOCK_INSERT_INTENTION 2048U/*!< this bit is set when we place a waiting
+				gap type record lock request in order to let
+				an insert of an index record to wait until
+				there are no conflicting locks by other
+				transactions on the gap; note that this flag
+				remains set when the waiting lock is granted,
+				or if the lock is inherited to a neighboring
+				record */
+#define LOCK_PREDICATE	8192U	/*!< Predicate lock */
+#define LOCK_PRDT_PAGE	16384U	/*!< Page lock */
+
+
+#if (LOCK_WAIT|LOCK_GAP|LOCK_REC_NOT_GAP|LOCK_INSERT_INTENTION|LOCK_PREDICATE|LOCK_PRDT_PAGE)&LOCK_MODE_MASK
+# error
+#endif
+#if (LOCK_WAIT|LOCK_GAP|LOCK_REC_NOT_GAP|LOCK_INSERT_INTENTION|LOCK_PREDICATE|LOCK_PRDT_PAGE)&LOCK_TYPE_MASK
+# error
+#endif
+/* @} */
+
+/** Lock struct; protected by lock_sys->mutex */
+struct ib_lock_t
+{
+	trx_t*		trx;		/*!< transaction owning the
+					lock */
+	UT_LIST_NODE_T(ib_lock_t)
+			trx_locks;	/*!< list of the locks of the
+					transaction */
+
+	dict_index_t*	index;		/*!< index for a record lock */
+
+	ib_lock_t*	hash;		/*!< hash chain node for a record
+					lock. The link node in a singly linked
+					list, used during hashing. */
+
+	/* 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 */
+
+	union {
+		lock_table_t	tab_lock;/*!< table lock */
+		lock_rec_t	rec_lock;/*!< record lock */
+	} un_member;			/*!< lock details */
+
+	ib_uint32_t	type_mode;	/*!< lock type, mode, LOCK_GAP or
+					LOCK_REC_NOT_GAP,
+					LOCK_INSERT_INTENTION,
+					wait flag, ORed */
+
+	/** Determine if the lock object is a record lock.
+	@return true if record lock, false otherwise. */
+	bool is_record_lock() const
+	{
+		return(type() == LOCK_REC);
+	}
+
+	bool is_waiting() const
+	{
+		return(type_mode & LOCK_WAIT);
+	}
+
+	bool is_gap() const
+	{
+		return(type_mode & LOCK_GAP);
+	}
+
+	bool is_record_not_gap() const
+	{
+		return(type_mode & LOCK_REC_NOT_GAP);
+	}
+
+	bool is_insert_intention() const
+	{
+		return(type_mode & LOCK_INSERT_INTENTION);
+	}
+
+	ulint type() const {
+		return(type_mode & LOCK_TYPE_MASK);
+	}
+
+	enum lock_mode mode() const
+	{
+		return(static_cast<enum lock_mode>(type_mode & LOCK_MODE_MASK));
+	}
+
+	/** Print the lock object into the given output stream.
+	@param[in,out]	out	the output stream
+	@return the given output stream. */
+	std::ostream& print(std::ostream& out) const;
+
+	/** Convert the member 'type_mode' into a human readable string.
+	@return human readable string */
+	std::string type_mode_string() const;
+
+	const char* type_string() const
+	{
+		switch (type_mode & LOCK_TYPE_MASK) {
+		case LOCK_REC:
+			return("LOCK_REC");
+		case LOCK_TABLE:
+			return("LOCK_TABLE");
+		default:
+			ut_error;
+		}
+	}
+};
+
+typedef UT_LIST_BASE_NODE_T(ib_lock_t) trx_lock_list_t;
 
 #endif /* lock0types_h */
diff --git a/storage/innobase/include/trx0trx.h b/storage/innobase/include/trx0trx.h
index 6ed69e6c5c4..adfe4f41955 100644
--- a/storage/innobase/include/trx0trx.h
+++ b/storage/innobase/include/trx0trx.h
@@ -704,13 +704,19 @@ struct trx_lock_t {
 					only be modified by the thread that is
 					serving the running transaction. */
 
-	lock_pool_t	rec_pool;	/*!< Pre-allocated record locks */
+	/** Pre-allocated record locks */
+	struct {
+		ib_lock_t lock; byte pad[256];
+	} rec_pool[8];
 
-	lock_pool_t	table_pool;	/*!< Pre-allocated table locks */
+	/** Pre-allocated table locks */
+	ib_lock_t	table_pool[8];
 
-	ulint		rec_cached;	/*!< Next free rec lock in pool */
+	/** Next available rec_pool[] entry */
+	unsigned	rec_cached;
 
-	ulint		table_cached;	/*!< Next free table lock in pool */
+	/** Next available table_pool[] entry */
+	unsigned	table_cached;
 
 	mem_heap_t*	lock_heap;	/*!< memory heap for trx_locks;
 					protected by lock_sys->mutex */
diff --git a/storage/innobase/lock/lock0lock.cc b/storage/innobase/lock/lock0lock.cc
index 61f62d1e054..18e4c164860 100644
--- a/storage/innobase/lock/lock0lock.cc
+++ b/storage/innobase/lock/lock0lock.cc
@@ -59,18 +59,6 @@ ulong innodb_lock_schedule_algorithm;
 /** The value of innodb_deadlock_detect */
 my_bool	innobase_deadlock_detect;
 
-/** Total number of cached record locks */
-static const ulint	REC_LOCK_CACHE = 8;
-
-/** Maximum record lock size in bytes */
-static const ulint	REC_LOCK_SIZE = sizeof(ib_lock_t) + 256;
-
-/** Total number of cached table locks */
-static const ulint	TABLE_LOCK_CACHE = 8;
-
-/** Size in bytes, of the table lock instance */
-static const ulint	TABLE_LOCK_SIZE = sizeof(ib_lock_t);
-
 /*********************************************************************//**
 Checks if a waiting record lock request still has to wait in a queue.
 @return lock that is causing the wait */
@@ -1469,13 +1457,13 @@ lock_rec_create_low(
 		}
 	}
 
- 	if (trx->lock.rec_cached >= trx->lock.rec_pool.size()
-	    || sizeof *lock + n_bytes > REC_LOCK_SIZE) {
+	if (trx->lock.rec_cached >= UT_ARR_SIZE(trx->lock.rec_pool)
+	    || sizeof *lock + n_bytes > sizeof *trx->lock.rec_pool) {
 		lock = static_cast<lock_t*>(
 			mem_heap_alloc(trx->lock.lock_heap,
 				       sizeof *lock + n_bytes));
 	} else {
-		lock = trx->lock.rec_pool[trx->lock.rec_cached++];
+		lock = &trx->lock.rec_pool[trx->lock.rec_cached++].lock;
 	}
 
 	lock->trx = trx;
@@ -3653,8 +3641,9 @@ lock_table_create(
 
 		ib_vector_push(trx->autoinc_locks, &lock);
 
-	} else if (trx->lock.table_cached < trx->lock.table_pool.size()) {
-		lock = trx->lock.table_pool[trx->lock.table_cached++];
+	} else if (trx->lock.table_cached
+		   < UT_ARR_SIZE(trx->lock.table_pool)) {
+		lock = &trx->lock.table_pool[trx->lock.table_cached++];
 	} else {
 
 		lock = static_cast<lock_t*>(
@@ -7678,33 +7667,6 @@ DeadlockChecker::check_and_resolve(const lock_t* lock, trx_t* trx)
 	return(victim_trx);
 }
 
-/**
-Allocate cached locks for the transaction.
-@param trx		allocate cached record locks for this transaction */
-void
-lock_trx_alloc_locks(trx_t* trx)
-{
-	ulint	sz = REC_LOCK_SIZE * REC_LOCK_CACHE;
-	byte*	ptr = reinterpret_cast<byte*>(ut_malloc_nokey(sz));
-
-	/* We allocate one big chunk and then distribute it among
-	the rest of the elements. The allocated chunk pointer is always
-	at index 0. */
-
-	for (ulint i = 0; i < REC_LOCK_CACHE; ++i, ptr += REC_LOCK_SIZE) {
-		trx->lock.rec_pool.push_back(
-			reinterpret_cast<ib_lock_t*>(ptr));
-	}
-
-	sz = TABLE_LOCK_SIZE * TABLE_LOCK_CACHE;
-	ptr = reinterpret_cast<byte*>(ut_malloc_nokey(sz));
-
-	for (ulint i = 0; i < TABLE_LOCK_CACHE; ++i, ptr += TABLE_LOCK_SIZE) {
-		trx->lock.table_pool.push_back(
-			reinterpret_cast<ib_lock_t*>(ptr));
-	}
-
-}
 /*************************************************************//**
 Updates the lock table when a page is split and merged to
 two pages. */
diff --git a/storage/innobase/trx/trx0trx.cc b/storage/innobase/trx/trx0trx.cc
index 7ebf41b3143..ae2611020de 100644
--- a/storage/innobase/trx/trx0trx.cc
+++ b/storage/innobase/trx/trx0trx.cc
@@ -190,10 +190,6 @@ struct TrxFactory {
 		the constructors of the trx_t members. */
 		new(&trx->mod_tables) trx_mod_tables_t();
 
-		new(&trx->lock.rec_pool) lock_pool_t();
-
-		new(&trx->lock.table_pool) lock_pool_t();
-
 		new(&trx->lock.table_locks) lock_pool_t();
 
 		trx_init(trx);
@@ -216,8 +212,6 @@ struct TrxFactory {
 
 		mutex_create(LATCH_ID_TRX, &trx->mutex);
 		mutex_create(LATCH_ID_TRX_UNDO, &trx->undo_mutex);
-
-		lock_trx_alloc_locks(trx);
 	}
 
 	/** Release resources held by the transaction object.
@@ -249,26 +243,6 @@ struct TrxFactory {
 
 		ut_ad(trx->read_view == NULL);
 
-		if (!trx->lock.rec_pool.empty()) {
-
-			/* See lock_trx_alloc_locks() why we only free
-			the first element. */
-
-			ut_free(trx->lock.rec_pool[0]);
-		}
-
-		if (!trx->lock.table_pool.empty()) {
-
-			/* See lock_trx_alloc_locks() why we only free
-			the first element. */
-
-			ut_free(trx->lock.table_pool[0]);
-		}
-
-		trx->lock.rec_pool.~lock_pool_t();
-
-		trx->lock.table_pool.~lock_pool_t();
-
 		trx->lock.table_locks.~lock_pool_t();
 	}
 
@@ -407,7 +381,12 @@ trx_create_low()
 
 	/* Should have been either just initialized or .clear()ed by
 	trx_free(). */
-	ut_a(trx->mod_tables.size() == 0);
+	ut_ad(trx->mod_tables.empty());
+	ut_ad(trx->lock.table_locks.empty());
+	ut_ad(UT_LIST_GET_LEN(trx->lock.trx_locks) == 0);
+	ut_ad(trx->lock.n_rec_locks == 0);
+	ut_ad(trx->lock.table_cached == 0);
+	ut_ad(trx->lock.rec_cached == 0);
 
 #ifdef WITH_WSREP
 	trx->wsrep_event = NULL;