#include "univ.i"
#include "sync0types.h"
#include "ut0lst.h"
#include "ut0mem.h"
#include "os0thread.h"
#include "os0sync.h"
#include "sync0arr.h"
#include "sync0sync.ic"

Include dependency graph for sync0sync.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures
struct	ib_mutex_t

Macros
#define	mutex_create(K, M, level) mutex_create_func((M), #M, (level), __FILE__, __LINE__)
#define	mutex_enter(M) mutex_enter_func((M), __FILE__, __LINE__)
#define	mutex_enter_nowait(M) mutex_enter_nowait_func((M), __FILE__, __LINE__)
#define	mutex_exit(M) mutex_exit_func(M)
#define	mutex_free(M) mutex_free_func(M)
#define	mutex_enter_fast(M) mutex_enter_func((M), __FILE__, __LINE__)
#define	sync_thread_levels_empty_except_dict() (!sync_thread_levels_nonempty_gen(TRUE))
#define	SYNC_USER_TRX_LOCK 9999
#define	SYNC_NO_ORDER_CHECK
#define	SYNC_LEVEL_VARYING
#define	SYNC_TRX_I_S_RWLOCK
#define	SYNC_TRX_I_S_LAST_READ
#define	SYNC_FILE_FORMAT_TAG
#define	SYNC_DICT_OPERATION
#define	SYNC_FTS_CACHE 1005 /* FTS cache rwlock */
#define	SYNC_DICT 1000
#define	SYNC_DICT_AUTOINC_MUTEX 999
#define	SYNC_STATS_AUTO_RECALC 997
#define	SYNC_DICT_HEADER 995
#define	SYNC_IBUF_HEADER 914
#define	SYNC_IBUF_PESS_INSERT_MUTEX 912
#define	SYNC_INDEX_TREE 900
#define	SYNC_TREE_NODE_NEW 892
#define	SYNC_TREE_NODE_FROM_HASH 891
#define	SYNC_TREE_NODE 890
#define	SYNC_PURGE_LATCH 800
#define	SYNC_TRX_UNDO 700
#define	SYNC_RSEG 600
#define	SYNC_RSEG_HEADER_NEW 591
#define	SYNC_RSEG_HEADER 590
#define	SYNC_TRX_UNDO_PAGE 570
#define	SYNC_EXTERN_STORAGE 500
#define	SYNC_FSP 400
#define	SYNC_FSP_PAGE 395
#define	SYNC_IBUF_MUTEX 370 /* ibuf_mutex */
#define	SYNC_IBUF_INDEX_TREE 360
#define	SYNC_IBUF_TREE_NODE_NEW 359
#define	SYNC_IBUF_TREE_NODE 358
#define	SYNC_IBUF_BITMAP_MUTEX 351
#define	SYNC_IBUF_BITMAP 350
#define	SYNC_INDEX_ONLINE_LOG 340
#define	SYNC_LOCK_WAIT_SYS 300
#define	SYNC_LOCK_SYS 299
#define	SYNC_TRX_SYS 298
#define	SYNC_TRX 297
#define	SYNC_THREADS 295
#define	SYNC_REC_LOCK 294
#define	SYNC_TRX_SYS_HEADER 290
#define	SYNC_PURGE_QUEUE 200
#define	SYNC_LOG 170
#define	SYNC_LOG_FLUSH_ORDER 147
#define	SYNC_RECV 168
#define	SYNC_FTS_TOKENIZE 167
#define	SYNC_FTS_CACHE_INIT 166 /* Used for FTS cache initialization */
#define	SYNC_FTS_BG_THREADS 165
#define	SYNC_FTS_OPTIMIZE 164
#define	SYNC_WORK_QUEUE 162
#define	SYNC_SEARCH_SYS
#define	SYNC_BUF_POOL 150 /* Buffer pool mutex */
#define	SYNC_BUF_PAGE_HASH 149 /* buf_pool->page_hash rw_lock */
#define	SYNC_BUF_BLOCK 146 /* Block mutex */
#define	SYNC_BUF_FLUSH_LIST 145 /* Buffer flush list mutex */
#define	SYNC_DOUBLEWRITE 140
#define	SYNC_ANY_LATCH 135
#define	SYNC_MEM_HASH 131
#define	SYNC_MEM_POOL 130
#define	RW_LOCK_NOT_LOCKED 350
#define	RW_LOCK_EX 351
#define	RW_LOCK_EXCLUSIVE 351
#define	RW_LOCK_SHARED 352
#define	RW_LOCK_WAIT_EX 353
#define	SYNC_MUTEX 354
#define	MUTEX_MAGIC_N 979585UL
#define	SYNC_SPIN_ROUNDS srv_n_spin_wait_rounds

Typedefs
typedef byte	lock_word_t
typedef ut_list_base< ib_mutex_t >	ut_list_base_node_t

Functions
UNIV_INTERN void	sync_init (void)
UNIV_INTERN void	sync_close (void)
UNIV_INTERN void	mutex_create_func (ib_mutex_t mutex, const char cmutex_name, ulint level, const char *cfile_name, ulint cline)
UNIV_INTERN void	mutex_free_func (ib_mutex_t *mutex)
UNIV_INLINE void	mutex_enter_func (ib_mutex_t mutex, const char file_name, ulint line)
UNIV_INTERN ulint	mutex_enter_nowait_func (ib_mutex_t mutex, const char file_name, ulint line)
UNIV_INLINE void	mutex_exit_func (ib_mutex_t *mutex)
UNIV_INTERN ibool	sync_all_freed (void)
UNIV_INTERN void	sync_print_wait_info (FILE *file)
UNIV_INTERN void	sync_print (FILE *file)
UNIV_INTERN ibool	mutex_validate (const ib_mutex_t *mutex)
UNIV_INTERN ibool	mutex_own (const ib_mutex_t *mutex))
UNIV_INTERN void	sync_thread_add_level (void *latch, ulint level, ibool relock))
UNIV_INTERN ibool	sync_thread_reset_level (void *latch)
UNIV_INTERN void *	sync_thread_levels_contains (ulint level)
UNIV_INTERN void *	sync_thread_levels_nonempty_gen (ibool dict_mutex_allowed))
UNIV_INTERN void *	sync_thread_levels_nonempty_trx (ibool has_search_latch))
UNIV_INTERN void	mutex_get_debug_info (ib_mutex_t mutex, const char file_name, ulint line, os_thread_id_t *thread_id)
UNIV_INTERN ulint	mutex_n_reserved (void)
UNIV_INLINE lock_word_t	mutex_get_lock_word (const ib_mutex_t *mutex)
UNIV_INLINE ulint	mutex_get_waiters (const ib_mutex_t *mutex)
UNIV_INLINE void	os_atomic_dec_ulint_func (ib_mutex_t mutex, volatile ulint var, ulint delta)
UNIV_INLINE void	os_atomic_inc_ulint_func (ib_mutex_t mutex, volatile ulint var, ulint delta)

Variables
my_bool	timed_mutexes
ib_int64_t	mutex_exit_count
ibool	sync_order_checks_on
ibool	sync_initialized
ut_list_base_node_t	mutex_list
ib_mutex_t	mutex_list_mutex

Detailed Description

Mutex, the basic synchronization primitive

Created 9/5/1995 Heikki Tuuri

Macro Definition Documentation

#define mutex_enter_fast ( M ) mutex_enter_func((M), __FILE__, __LINE__)

NOTE! The following macro should be used in mutex locking, not the corresponding function.

#define MUTEX_MAGIC_N 979585UL

Value of mutex_t::magic_n

#define SYNC_DICT_OPERATION

Value:

1010    /* table create, drop, etc. reserve
                                        this in X-mode; implicit or backround
                                        operations purge, rollback, foreign
                                        key checks reserve this in S-mode */

#define SYNC_FILE_FORMAT_TAG

Value:

1200 /* Used to serialize access to the

file format tag */

#define SYNC_LEVEL_VARYING

Value:

2000    /* Level is varying. Only used with
                                        buffer pool page locks, which do not
                                        have a fixed level, but instead have
                                        their level set after the page is
                                        locked; see e.g.
                                        ibuf_bitmap_get_map_page(). */

#define SYNC_NO_ORDER_CHECK

Value:

3000 /* this can be used to suppress

latching order checking */

#define SYNC_SEARCH_SYS

Value:

160     /* NOTE that if we have a memory
                                        heap that can be extended to the
                                        buffer pool, its logical level is
                                        SYNC_SEARCH_SYS, as memory allocation
                                        can call routines there! Otherwise
                                        the level is SYNC_MEM_HASH. */

#define SYNC_SPIN_ROUNDS srv_n_spin_wait_rounds

Constant determining how long spin wait is continued before suspending

the thread. A value 600 rounds on a 1995 100 MHz Pentium seems to correspond to 20 microseconds.

#define sync_thread_levels_empty_except_dict ( ) (!sync_thread_levels_nonempty_gen(TRUE))

Checks if the level array for the current thread is empty, except for data dictionary latches.

#define SYNC_TRX_I_S_LAST_READ

Value:

1900 /* Used for

trx_i_s_cache_t::last_read_mutex */

#define SYNC_TRX_I_S_RWLOCK

Value:

1910 /* Used for

trx_i_s_cache_t::rw_lock */

Typedef Documentation

typedef ut_list_base< ib_mutex_t > ut_list_base_node_t

Global list of database mutexes (not OS mutexes) created.

Function Documentation

UNIV_INTERN void mutex_create_func	(	ib_mutex_t *	mutex,
		const char *	cmutex_name,
		ulint	level,
		const char *	cfile_name,
		ulint	cline
	)

Creates, or rather, initializes a mutex object in a specified memory location (which must be appropriately aligned). The mutex is initialized in the reset state. Explicit freeing of the mutex with mutex_free is necessary only if the memory block containing it is freed. in: file line where created

Parameters

mutex	in: pointer to memory
cmutex_name	in: mutex name
level	in: level
cfile_name	in: file name where created

UNIV_INLINE void mutex_enter_func	(	ib_mutex_t *	mutex,
		const char *	file_name,
		ulint	line
	)

NOTE! Use the corresponding macro in the header file, not this function directly. Locks a mutex for the current thread. If the mutex is reserved the function spins a preset time (controlled by SYNC_SPIN_ROUNDS) waiting for the mutex before suspending the thread. in: line where locked

Locks a mutex for the current thread. If the mutex is reserved, the function spins a preset time (controlled by SYNC_SPIN_ROUNDS), waiting for the mutex before suspending the thread.

Parameters

mutex	in: pointer to mutex
file_name	in: file name where locked
line	in: line where locked

UNIV_INTERN ulint mutex_enter_nowait_func	(	ib_mutex_t *	mutex,
		const char *	file_name,
		ulint	line
	)

NOTE! Use the corresponding macro in the header file, not this function directly. Tries to lock the mutex for the current thread. If the lock is not acquired immediately, returns with return value 1.

Returns: 0 if succeed, 1 if not in: line where requested

Parameters

mutex	in: pointer to mutex
file_name	in: file name where mutex requested

UNIV_INLINE void mutex_exit_func ( ib_mutex_t * mutex )

NOTE! Use the corresponding macro mutex_exit(), not directly this function! Unlocks a mutex owned by the current thread. in: pointer to mutex

NOTE! Use the corresponding macro mutex_exit(), not directly this function! Unlocks a mutex owned by the current thread.

Parameters

mutex in: pointer to mutex

UNIV_INTERN void mutex_free_func ( ib_mutex_t * mutex )

NOTE! Use the corresponding macro mutex_free(), not directly this function! Calling this function is obligatory only if the memory buffer containing the mutex is freed. Removes a mutex object from the mutex list. The mutex is checked to be in the reset state. in: mutex

UNIV_INTERN void mutex_get_debug_info	(	ib_mutex_t *	mutex,
		const char **	file_name,
		ulint *	line,
		os_thread_id_t *	thread_id
	)

Gets the debug information for a reserved mutex. out: id of the thread which owns the mutex

Parameters

mutex	in: mutex
file_name	out: file where requested
line	out: line where requested

UNIV_INLINE lock_word_t mutex_get_lock_word ( const ib_mutex_t * mutex )

NOT to be used outside this module except in debugging! Gets the value of the lock word. in: mutex

Gets the value of the lock word.

Parameters

mutex in: mutex

UNIV_INLINE ulint mutex_get_waiters ( const ib_mutex_t * mutex )

NOT to be used outside this module except in debugging! Gets the waiters field in a mutex.

Returns: value to set in: mutex

Gets the waiters field in a mutex.

Returns: value to set

< declared volatile to ensure that the value is read from memory

Parameters

mutex in: mutex

UNIV_INTERN ulint mutex_n_reserved ( void )

Counts currently reserved mutexes. Works only in the debug version.

Returns: number of reserved mutexes

UNIV_INTERN ibool mutex_own ( const ib_mutex_t * mutex )

Checks that the current thread owns the mutex. Works only in the debug version.

Returns: TRUE if owns

Parameters

mutex in: mutex

UNIV_INTERN ibool mutex_validate ( const ib_mutex_t * mutex )

Checks that the mutex has been initialized.

Returns: TRUE in: mutex

UNIV_INLINE void os_atomic_dec_ulint_func	(	ib_mutex_t *	mutex,
		volatile ulint *	var,
		ulint	delta
	)

Function that uses a mutex to decrement a variable atomically in: delta to decrement

Function that uses a mutex to decrement a variable atomically

Parameters

mutex	in: mutex guarding the dec
var	in/out: variable to decrement
delta	in: delta to decrement

UNIV_INLINE void os_atomic_inc_ulint_func	(	ib_mutex_t *	mutex,
		volatile ulint *	var,
		ulint	delta
	)

Function that uses a mutex to increment a variable atomically in: delta to increment

Function that uses a mutex to increment a variable atomically

Parameters

mutex	in: mutex guarding the increment
var	in/out: variable to increment
delta	in: delta to increment

UNIV_INTERN ibool sync_all_freed ( void )

Returns TRUE if no mutex or rw-lock is currently locked. Works only in the debug version.

Returns: TRUE if no mutexes and rw-locks reserved

UNIV_INTERN void sync_close ( void )

Frees the resources in synchronization data structures.

UNIV_INTERN void sync_init ( void )

Initializes the synchronization data structures.

UNIV_INTERN void sync_print ( FILE * file )

Prints info of the sync system. in: file where to print

UNIV_INTERN void sync_print_wait_info ( FILE * file )

Prints wait info of the sync system. in: file where to print

UNIV_INTERN void sync_thread_add_level	(	void *	latch,
		ulint	level,
		ibool	relock
	)

Adds a latch and its level in the thread level array. Allocates the memory for the array if called first time for this OS thread. Makes the checks against other latch levels stored in the array for this thread.

Parameters

latch	in: pointer to a mutex or an rw-lock
level	in: level in the latching order; if SYNC_LEVEL_VARYING, nothing is done
relock	in: TRUE if re-entering an x-lock

UNIV_INTERN void* sync_thread_levels_contains ( ulint level )

Checks if the level array for the current thread contains a mutex or rw-latch at the specified level.

Returns: a matching latch, or NULL if not found in: latching order level (SYNC_DICT, ...)

UNIV_INTERN void* sync_thread_levels_nonempty_gen ( ibool dict_mutex_allowed )

Checks that the level array for the current thread is empty.

Returns: a latch, or NULL if empty except the exceptions specified below

Parameters

dict_mutex_allowed in: TRUE if dictionary mutex is allowed to be owned by the thread

UNIV_INTERN void* sync_thread_levels_nonempty_trx ( ibool has_search_latch )

Checks if the level array for the current thread is empty, except for the btr_search_latch.

Returns: a latch, or NULL if empty except the exceptions specified below

Parameters

has_search_latch in: TRUE if and only if the thread is supposed to hold btr_search_latch

UNIV_INTERN ibool sync_thread_reset_level ( void * latch )

Removes a latch from the thread level array if it is found there.

Returns: TRUE if found in the array; it is no error if the latch is not found, as we presently are not able to determine the level for every latch reservation the program does in: pointer to a mutex or an rw-lock

Variable Documentation

ib_int64_t mutex_exit_count

The number of mutex_exit calls. Intended for performance monitoring.

ut_list_base_node_t mutex_list

Global list of database mutexes (not OS mutexes) created.

ib_mutex_t mutex_list_mutex

Mutex protecting the mutex_list variable

ibool sync_initialized

This variable is set to TRUE when sync_init is called

ibool sync_order_checks_on

Latching order checks start when this is set TRUE

Data Structures

Macros

Typedefs

Functions

Variables

Detailed Description

Macro Definition Documentation

Typedef Documentation

Function Documentation

Variable Documentation