/********************************************************************
Creates the memory copies for the rollback segments and initializes the
rseg list and array in trx_sys at a database startup. */
static
void
trx_rseg_create_instance(
/*=====================*/
trx_sysf_t* sys_header, /*!< in: trx system header */
mtr_t* mtr) /*!< in: mtr */
{
ulint i;
for (i = 0; i < TRX_SYS_N_RSEGS; i++) {
ulint page_no;
page_no = trx_sysf_rseg_get_page_no(sys_header, i, mtr);
if (page_no == FIL_NULL) {
trx_sys_set_nth_rseg(trx_sys, i, NULL);
} else {
ulint space;
ulint zip_size;
trx_rseg_t* rseg = NULL;
ut_a(!trx_rseg_get_on_id(i));
space = trx_sysf_rseg_get_space(sys_header, i, mtr);
zip_size = space ? fil_space_get_zip_size(space) : 0;
rseg = trx_rseg_mem_create(
i, space, zip_size, page_no, mtr);
ut_a(rseg->id == i);
}
}
}
void
trx_rseg_list_and_array_init(
/*=========================*/
trx_sysf_t* sys_header, /* in: trx system header */
mtr_t* mtr) /* in: mtr */
{
ulint i;
ulint page_no;
ulint space;
UT_LIST_INIT(trx_sys->rseg_list);
trx_sys->rseg_history_len = 0;
for (i = 0; i < TRX_SYS_N_RSEGS; i++) {
page_no = trx_sysf_rseg_get_page_no(sys_header, i, mtr);
if (page_no == FIL_NULL) {
trx_sys_set_nth_rseg(trx_sys, i, NULL);
} else {
space = trx_sysf_rseg_get_space(sys_header, i, mtr);
trx_rseg_mem_create(i, space, page_no, mtr);
}
}
}
/*********************************************************************
Creates a rollback segment.
@return pointer to new rollback segment if create successful */
UNIV_INTERN
trx_rseg_t*
trx_rseg_create(void)
/*=================*/
{
mtr_t mtr;
ulint slot_no;
trx_rseg_t* rseg = NULL;
mtr_start(&mtr);
/* To obey the latching order, acquire the file space
x-latch before the kernel mutex. */
mtr_x_lock(fil_space_get_latch(TRX_SYS_SPACE, NULL), &mtr);
mutex_enter(&kernel_mutex);
slot_no = trx_sysf_rseg_find_free(&mtr);
if (slot_no != ULINT_UNDEFINED) {
ulint space;
ulint page_no;
ulint zip_size;
trx_sysf_t* sys_header;
page_no = trx_rseg_header_create(
TRX_SYS_SPACE, 0, ULINT_MAX, slot_no, &mtr);
ut_a(page_no != FIL_NULL);
ut_ad(!trx_rseg_get_on_id(slot_no));
sys_header = trx_sysf_get(&mtr);
space = trx_sysf_rseg_get_space(sys_header, slot_no, &mtr);
zip_size = space ? fil_space_get_zip_size(space) : 0;
rseg = trx_rseg_mem_create(
slot_no, space, zip_size, page_no, &mtr);
}
mutex_exit(&kernel_mutex);
mtr_commit(&mtr);
return(rseg);
}
