fis-gtm/sr_unix/rel_lock.c

92 lines
3.0 KiB
C

/****************************************************************
* *
* Copyright 2001, 2012 Fidelity Information Services, Inc *
* *
* This source code contains the intellectual property *
* of its copyright holder(s), and is made available *
* under a license. If you do not know the terms of *
* the license, please stop and do not read further. *
* *
****************************************************************/
#include "mdef.h"
#include <errno.h>
#include <signal.h> /* for VSIG_ATOMIC_T type */
#include "gdsroot.h"
#include "gtm_facility.h"
#include "fileinfo.h"
#include "gdsbt.h"
#include "gdsfhead.h"
#include "filestruct.h"
#include "gtmsiginfo.h"
#include "mutex.h"
#include "deferred_signal_handler.h"
#include "have_crit.h"
#include "caller_id.h"
#include "jnl.h"
GBLREF volatile int4 crit_count;
GBLREF uint4 process_id;
GBLREF volatile int suspend_status;
GBLREF node_local_ptr_t locknl;
GBLREF volatile int4 gtmMallocDepth; /* Recursion indicator */
GBLREF jnl_gbls_t jgbl;
error_def(ERR_CRITRESET);
error_def(ERR_DBCCERR);
/* Note about usage of this function : Create dummy gd_region, gd_segment, file_control,
* unix_db_info, sgmnt_addrs, and allocate mutex_struct (and NUM_CRIT_ENTRY * mutex_que_entry),
* mutex_spin_parms_struct, and node_local in shared memory. Initialize the fields as in
* jnlpool_init(). Pass the address of the dummy region as argument to this function.
*/
void rel_lock(gd_region *reg)
{
unix_db_info *udi;
sgmnt_addrs *csa;
enum cdb_sc status;
udi = FILE_INFO(reg);
csa = &udi->s_addrs;
/* Assert that we never come into rel_lock with hold_onto_crit being TRUE. The only exception is for online rollback
* when it is done with the actual rollback and is now in mur_close_files to release crit. At this point it will have
* hold_onto_crit set to TRUE.
*/
assert(!csa->hold_onto_crit || (process_exiting && jgbl.onlnrlbk));
if (csa->now_crit)
{
assert(0 == crit_count);
crit_count++; /* prevent interrupts */
assert(csa->nl->in_crit == process_id || csa->nl->in_crit == 0);
CRIT_TRACE(crit_ops_rw); /* see gdsbt.h for comment on placement */
csa->nl->in_crit = 0;
DEBUG_ONLY(locknl = csa->nl;) /* for DEBUG_ONLY LOCK_HIST macro */
/* As of 10/07/98, crashcnt field in mutex_struct is not changed by any function for the dummy region */
status = mutex_unlockw(reg, 0);
DEBUG_ONLY(locknl = NULL;) /* restore "locknl" to default value */
if (status != cdb_sc_normal)
{
csa->now_crit = FALSE;
crit_count = 0;
if (status == cdb_sc_critreset)
rts_error(VARLSTCNT(4) ERR_CRITRESET, 2, REG_LEN_STR(reg));
else
{
assert(status == cdb_sc_dbccerr);
rts_error(VARLSTCNT(4) ERR_DBCCERR, 2, REG_LEN_STR(reg));
}
return;
}
crit_count = 0;
} else
{
CRIT_TRACE(crit_ops_nocrit);
}
/* Now that crit for THIS region is released, check if deferred signal/exit handling can be done and if so do it */
DEFERRED_EXIT_HANDLING_CHECK;
if ((DEFER_SUSPEND == suspend_status) && OK_TO_INTERRUPT)
suspend(SIGSTOP);
}