fis-gtm/sr_unix/grab_crit.c

148 lines
4.4 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 <signal.h> /* for VSIG_ATOMIC_T type */
#include "gdsroot.h"
#include "gtm_facility.h"
#include "fileinfo.h"
#include "gdsbt.h"
#include "gdsfhead.h"
#include "gdsbgtr.h"
#include "filestruct.h"
#include "send_msg.h"
#include "mutex.h"
#include "wcs_recover.h"
#include "deferred_signal_handler.h"
#include "caller_id.h"
#include "is_proc_alive.h"
#ifdef DEBUG
#include "gtm_stdio.h"
#include "gt_timer.h"
#include "wbox_test_init.h"
#include "repl_msg.h"
#include "gtmsource.h"
#include "jnl.h"
#endif
#include "gtmimagename.h"
#include "error.h"
GBLREF volatile int4 crit_count;
GBLREF short crash_count;
GBLREF uint4 process_id;
GBLREF node_local_ptr_t locknl;
#ifdef DEBUG
GBLREF jnlpool_addrs jnlpool;
GBLREF jnl_gbls_t jgbl;
#endif
GBLREF boolean_t mupip_jnl_recover;
error_def(ERR_CRITRESET);
error_def(ERR_DBCCERR);
error_def(ERR_DBFLCORRP);
void grab_crit(gd_region *reg)
{
unix_db_info *udi;
sgmnt_addrs *csa;
node_local_ptr_t cnl;
sgmnt_data_ptr_t csd;
enum cdb_sc status;
mutex_spin_parms_ptr_t mutex_spin_parms;
DEBUG_ONLY(sgmnt_addrs *jnlpool_csa;)
DCL_THREADGBL_ACCESS;
SETUP_THREADGBL_ACCESS;
udi = FILE_INFO(reg);
csa = &udi->s_addrs;
csd = csa->hdr;
cnl = csa->nl;
# ifdef DEBUG
if (gtm_white_box_test_case_enabled
&& (WBTEST_SENDTO_EPERM == gtm_white_box_test_case_number)
&& (0 == cnl->wbox_test_seq_num))
{
FPRINTF(stderr, "MUPIP BACKUP entered grab_crit\n");
cnl->wbox_test_seq_num = 1;
while (2 != cnl->wbox_test_seq_num)
LONG_SLEEP(1);
FPRINTF(stderr, "MUPIP BACKUP resumed in grab_crit\n");
cnl->wbox_test_seq_num = 3;
}
# endif
assert(!csa->hold_onto_crit);
if (!csa->now_crit)
{
# ifdef DEBUG
if (NULL != jnlpool.jnlpool_ctl)
{ /* We should never request crit on a database region while already holding the lock on the journal pool.
* Not following the protocol (obtaining lock on journal pool AFTER obtaining crit on database region),
* can lead to potential deadlocks
*/
assert((jnlpool.jnlpool_dummy_reg && jnlpool.jnlpool_dummy_reg->open) || jgbl.onlnrlbk);
jnlpool_csa = &FILE_INFO(jnlpool.jnlpool_dummy_reg)->s_addrs;
assert(!jnlpool_csa->now_crit);
}
# endif
assert(0 == crit_count);
crit_count++; /* prevent interrupts */
TREF(grabbing_crit) = reg;
DEBUG_ONLY(locknl = cnl;) /* for DEBUG_ONLY LOCK_HIST macro */
mutex_spin_parms = (mutex_spin_parms_ptr_t)&csd->mutex_spin_parms;
status = mutex_lockw(reg, mutex_spin_parms, crash_count);
# ifdef DEBUG
if (gtm_white_box_test_case_enabled
&& (WBTEST_SENDTO_EPERM == gtm_white_box_test_case_number)
&& (1 == cnl->wbox_test_seq_num))
{
FPRINTF(stderr, "MUPIP SET entered grab_crit\n");
cnl->wbox_test_seq_num = 2;
while (3 != cnl->wbox_test_seq_num)
LONG_SLEEP(1);
FPRINTF(stderr, "MUPIP SET resumed in grab_crit\n");
}
# endif
DEBUG_ONLY(locknl = NULL;) /* restore "locknl" to default value */
if (status != cdb_sc_normal)
{
crit_count = 0;
TREF(grabbing_crit) = NULL;
switch(status)
{
case cdb_sc_critreset:
rts_error(VARLSTCNT(4) ERR_CRITRESET, 2, REG_LEN_STR(reg));
case cdb_sc_dbccerr:
rts_error(VARLSTCNT(4) ERR_DBCCERR, 2, REG_LEN_STR(reg));
default:
GTMASSERT;
}
return;
}
/* There is only one case we know of when cnl->in_crit can be non-zero and that is when a process holding
* crit gets kill -9ed and another process ends up invoking "secshr_db_clnup" which in turn clears the
* crit semaphore (making it available for waiters) but does not also clear cnl->in_crit since it does not
* hold crit at that point. But in that case, the pid reported in cnl->in_crit should be dead. Check that.
*/
assert((0 == cnl->in_crit) || (FALSE == is_proc_alive(cnl->in_crit, 0)));
cnl->in_crit = process_id;
CRIT_TRACE(crit_ops_gw); /* see gdsbt.h for comment on placement */
TREF(grabbing_crit) = NULL;
crit_count = 0;
}
if (csd->file_corrupt && !mupip_jnl_recover)
rts_error(VARLSTCNT(4) ERR_DBFLCORRP, 2, DB_LEN_STR(reg));
if (csd->wc_blocked)
wcs_recover(reg);
return;
}