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Diffstat (limited to 'storage/innobase/include/sync0arr.h')
-rw-r--r-- | storage/innobase/include/sync0arr.h | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/storage/innobase/include/sync0arr.h b/storage/innobase/include/sync0arr.h new file mode 100644 index 00000000000..fecd910683e --- /dev/null +++ b/storage/innobase/include/sync0arr.h @@ -0,0 +1,127 @@ +/****************************************************** +The wait array used in synchronization primitives + +(c) 1995 Innobase Oy + +Created 9/5/1995 Heikki Tuuri +*******************************************************/ + +#ifndef sync0arr_h +#define sync0arr_h + +#include "univ.i" +#include "ut0lst.h" +#include "ut0mem.h" +#include "os0thread.h" + +typedef struct sync_cell_struct sync_cell_t; +typedef struct sync_array_struct sync_array_t; + +#define SYNC_ARRAY_OS_MUTEX 1 +#define SYNC_ARRAY_MUTEX 2 + +/*********************************************************************** +Creates a synchronization wait array. It is protected by a mutex +which is automatically reserved when the functions operating on it +are called. */ + +sync_array_t* +sync_array_create( +/*==============*/ + /* out, own: created wait array */ + ulint n_cells, /* in: number of cells in the array + to create */ + ulint protection); /* in: either SYNC_ARRAY_OS_MUTEX or + SYNC_ARRAY_MUTEX: determines the type + of mutex protecting the data structure */ +/********************************************************************** +Frees the resources in a wait array. */ + +void +sync_array_free( +/*============*/ + sync_array_t* arr); /* in, own: sync wait array */ +/********************************************************************** +Reserves a wait array cell for waiting for an object. +The event of the cell is reset to nonsignalled state. */ + +void +sync_array_reserve_cell( +/*====================*/ + sync_array_t* arr, /* in: wait array */ + void* object, /* in: pointer to the object to wait for */ + ulint type, /* in: lock request type */ + const char* file, /* in: file where requested */ + ulint line, /* in: line where requested */ + ulint* index); /* out: index of the reserved cell */ +/********************************************************************** +This function should be called when a thread starts to wait on +a wait array cell. In the debug version this function checks +if the wait for a semaphore will result in a deadlock, in which +case prints info and asserts. */ + +void +sync_array_wait_event( +/*==================*/ + sync_array_t* arr, /* in: wait array */ + ulint index); /* in: index of the reserved cell */ +/********************************************************************** +Frees the cell. NOTE! sync_array_wait_event frees the cell +automatically! */ + +void +sync_array_free_cell( +/*=================*/ + sync_array_t* arr, /* in: wait array */ + ulint index); /* in: index of the cell in array */ +/************************************************************************** +Looks for the cells in the wait array which refer +to the wait object specified, +and sets their corresponding events to the signaled state. In this +way releases the threads waiting for the object to contend for the object. +It is possible that no such cell is found, in which case does nothing. */ + +void +sync_array_signal_object( +/*=====================*/ + sync_array_t* arr, /* in: wait array */ + void* object);/* in: wait object */ +/************************************************************************** +If the wakeup algorithm does not work perfectly at semaphore relases, +this function will do the waking (see the comment in mutex_exit). This +function should be called about every 1 second in the server. */ + +void +sync_arr_wake_threads_if_sema_free(void); +/*====================================*/ +/************************************************************************** +Prints warnings of long semaphore waits to stderr. */ + +ibool +sync_array_print_long_waits(void); +/*=============================*/ + /* out: TRUE if fatal semaphore wait threshold + was exceeded */ +/************************************************************************ +Validates the integrity of the wait array. Checks +that the number of reserved cells equals the count variable. */ + +void +sync_array_validate( +/*================*/ + sync_array_t* arr); /* in: sync wait array */ +/************************************************************************** +Prints info of the wait array. */ + +void +sync_array_print_info( +/*==================*/ + FILE* file, /* in: file where to print */ + sync_array_t* arr); /* in: wait array */ + + +#ifndef UNIV_NONINL +#include "sync0arr.ic" +#endif + +#endif |