Fix Bug #56791 Remove ios_mutex from InnoDB code

rb://495 approved by Inaam

storage/innobase/handler/ha_innodb.cc

@@ -240,7 +240,6 @@ static PSI_mutex_info all_innodb_mutexes[] = {
 	{&ibuf_mutex_key, "ibuf_mutex", 0},
 	{&ibuf_pessimistic_insert_mutex_key,
 		 "ibuf_pessimistic_insert_mutex", 0},
-	{&ios_mutex_key, "ios_mutex", 0},
 	{&kernel_mutex_key, "kernel_mutex", 0},
 	{&log_sys_mutex_key, "log_sys_mutex", 0},
 #  ifdef UNIV_MEM_DEBUG

storage/innobase/include/sync0sync.h

@@ -85,7 +85,6 @@ extern mysql_pfs_key_t	hash_table_mutex_key;
 extern mysql_pfs_key_t	ibuf_bitmap_mutex_key;
 extern mysql_pfs_key_t	ibuf_mutex_key;
 extern mysql_pfs_key_t	ibuf_pessimistic_insert_mutex_key;
-extern mysql_pfs_key_t	ios_mutex_key;
 extern mysql_pfs_key_t	log_sys_mutex_key;
 extern mysql_pfs_key_t	log_flush_order_mutex_key;
 extern mysql_pfs_key_t	kernel_mutex_key;

storage/innobase/srv/srv0start.c

@@ -120,11 +120,6 @@ UNIV_INTERN enum srv_shutdown_state	srv_shutdown_state = SRV_SHUTDOWN_NONE;
 /** Files comprising the system tablespace */
 static os_file_t	files[1000];
 
-/** Mutex protecting the ios count */
-static mutex_t		ios_mutex;
-/** Count of I/O operations in io_handler_thread() */
-static ulint		ios;
-
 /** io_handler_thread parameters for thread identification */
 static ulint		n[SRV_MAX_N_IO_THREADS + 6];
 /** io_handler_thread identifiers */
@@ -152,11 +147,6 @@ UNIV_INTERN mysql_pfs_key_t	srv_master_thread_key;
 UNIV_INTERN mysql_pfs_key_t	srv_purge_thread_key;
 #endif /* UNIV_PFS_THREAD */
 
-#ifdef UNIV_PFS_MUTEX
-/* Key to register ios_mutex_key with performance schema */
-UNIV_INTERN mysql_pfs_key_t	ios_mutex_key;
-#endif /* UNIV_PFS_MUTEX */
-
 /*********************************************************************//**
 Convert a numeric string that optionally ends in G or M, to a number
 containing megabytes.
@@ -491,10 +481,6 @@ io_handler_thread(
 
 	while (srv_shutdown_state != SRV_SHUTDOWN_EXIT_THREADS) {
 		fil_aio_wait(segment);
-
-		mutex_enter(&ios_mutex);
-		ios++;
-		mutex_exit(&ios_mutex);
 	}
 
 	/* We count the number of threads in os_thread_exit(). A created
@@ -998,10 +984,6 @@ open_or_create_data_files(
 				srv_data_file_is_raw_partition[i] != 0);
 	}
 
-	ios = 0;
-
-	mutex_create(ios_mutex_key, &ios_mutex, SYNC_NO_ORDER_CHECK);
-
 	return(DB_SUCCESS);
 }