fis-gtm/sr_port/mlk_lock.c

199 lines
6.3 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 <stddef.h>
#include "gtm_string.h" /* for memcpy */
#include "gdsroot.h"
#include "gtm_facility.h"
#include "fileinfo.h"
#include "gdsbt.h"
#include "gdsfhead.h"
#include "filestruct.h"
#include "mlkdef.h"
#include "lockdefs.h"
#include "cdb_sc.h"
#include "jnl.h"
#include "gdscc.h"
#include "gdskill.h"
#include "buddy_list.h" /* needed for tp.h */
#include "hashtab_int4.h" /* needed for tp.h */
#include "tp.h"
#include "gtmimagename.h"
#include "cmidef.h" /* for cmmdef.h */
#include "hashtab_mname.h" /* needed for cmmdef.h */
#include "cmmdef.h" /* for curr_entry structure definition */
/* Include prototypes */
#include "mlk_garbage_collect.h"
#include "mlk_prcblk_add.h"
#include "mlk_prcblk_delete.h"
#include "mlk_shrblk_find.h"
#include "mlk_lock.h"
#include "t_retry.h"
#include "gvusr.h"
#ifdef VMS
GBLREF uint4 image_count;
GBLREF int4 login_time[2];
#endif
GBLREF int4 process_id;
GBLREF short crash_count;
GBLREF uint4 dollar_tlevel;
GBLREF unsigned int t_tries;
GBLREF tp_region *tp_reg_free_list; /* Ptr to list of tp_regions that are unused */
GBLREF tp_region *tp_reg_list; /* Ptr to list of tp_regions for this transaction */
error_def(ERR_LOCKSPACEFULL);
error_def(ERR_LOCKSPACEINFO);
error_def(ERR_GCBEFORE);
error_def(ERR_GCAFTER);
/*
* ------------------------------------------------------
* mlk_lock()
* Low level lock.
*
* Return:
* 0 - Locked
* > 0 - number of times blocked process was woken up
* ------------------------------------------------------
*/
uint4 mlk_lock(mlk_pvtblk *p,
UINTPTR_T auxown,
bool new)
{
mlk_ctldata_ptr_t ctl;
mlk_shrblk_ptr_t d;
int siz, retval, status;
boolean_t blocked, was_crit, have_space;
sgmnt_addrs *csa;
connection_struct *curr_entry; /* for GT.CM GNP server */
if (p->region->dyn.addr->acc_meth != dba_usr)
{
csa = &FILE_INFO(p->region)->s_addrs;
ctl = p->ctlptr;
if (csa->critical)
crash_count = csa->critical->crashcnt;
if (dollar_tlevel && !((t_tries < CDB_STAGNATE) || csa->now_crit)) /* Final retry and region not locked down */
{ /* make sure this region is in the list in case we end up retrying */
insert_region(p->region, &tp_reg_list, &tp_reg_free_list, SIZEOF(tp_region));
/* insert_region() will additionally attempt CRIT on the region and restart if not possible */
assert(csa->now_crit);
}
if (FALSE == (was_crit = csa->now_crit))
grab_crit(p->region);
retval = ctl->wakeups;
assert(retval);
/* this calculation is size of basic mlk_shrsub blocks plus the padded value length
that already contains the consideration for the length byte. This is so we get
room to put a bunch of nicely aligned blocks so the compiler can give us its
best shot at efficient code. */
siz = MLK_PVTBLK_SHRSUB_SIZE(p, p->subscript_cnt);
assert(siz >= 0);
assert(ctl->blkcnt >= 0);
have_space = TRUE;
if (ctl->subtop - ctl->subfree < siz || ctl->blkcnt < p->subscript_cnt)
{
mlk_garbage_collect(ctl, siz, p);
/* If there isn't any created space after garbage collection, don't attempt to lock anything. */
if (ctl->subtop - ctl->subfree < siz || ctl->blkcnt < p->subscript_cnt)
have_space = FALSE;
}
if (have_space)
blocked = mlk_shrblk_find(p, &d, auxown);
else
d = NULL;
if (NULL != d)
{
if (d->owner)
{ /* The lock already exists */
if (d->owner == process_id && d->auxowner == auxown)
{ /* We are already the owner */
p->nodptr = d;
retval = 0;
} else
{ /* Someone else has it. Block on it */
if (new)
mlk_prcblk_add(p->region, ctl, d, process_id);
p->nodptr = d;
p->sequence = d->sequence;
csa->hdr->trans_hist.lock_sequence++;
}
} else
{ /* Lock was not previously owned */
if (blocked)
{ /* We can't have it right now because of child or parent locks */
if (new)
mlk_prcblk_add(p->region, ctl, d, process_id);
p->nodptr = d;
p->sequence = d->sequence;
csa->hdr->trans_hist.lock_sequence++;
} else
{ /* The lock is graciously granted */
if (!new)
mlk_prcblk_delete(ctl, d, process_id);
d->owner = process_id;
d->auxowner = auxown;
if (auxown && IS_GTCM_GNP_SERVER_IMAGE)
{ /* called from gtcml_lock_internal() */
curr_entry = (connection_struct *)auxown;
d->auxpid = curr_entry->pvec->jpv_pid;
assert(SIZEOF(curr_entry->pvec->jpv_node) <= SIZEOF(d->auxnode));
memcpy(d->auxnode,
&curr_entry->pvec->jpv_node[0], SIZEOF(curr_entry->pvec->jpv_node));
/* cases of calls from omi_prc_lock() and rc_prc_lock() are not currently handled */
}
d->sequence = p->sequence = csa->hdr->trans_hist.lock_sequence++;
MLK_LOGIN(d);
p->nodptr = d;
retval = 0;
}
}
} else if (!csa->nl->lockspacefull_logged)
{ /* Needed to create a shrblk but no space was available. Resource starve. Print LOCKSPACEFULL to syslog
* and prevent printing LOCKSPACEFULL until (free space)/(lock space) ratio is above
* LOCK_SPACE_FULL_SYSLOG_THRESHOLD.
*/
csa->nl->lockspacefull_logged = TRUE;
send_msg(VARLSTCNT(4) ERR_LOCKSPACEFULL, 2, DB_LEN_STR(p->region));
if (ctl->subtop - ctl->subfree >= siz)
{
send_msg(VARLSTCNT(10) ERR_LOCKSPACEINFO, 8, REG_LEN_STR(p->region),
(ctl->max_prccnt - ctl->prccnt), ctl->max_prccnt,
(ctl->max_blkcnt - ctl->blkcnt), ctl->max_blkcnt, LEN_AND_LIT(" not "));
} else
{
send_msg(VARLSTCNT(10) ERR_LOCKSPACEINFO, 8, REG_LEN_STR(p->region),
(ctl->max_prccnt - ctl->prccnt), ctl->max_prccnt,
(ctl->max_blkcnt - ctl->blkcnt), ctl->max_blkcnt, LEN_AND_LIT(" "));
}
}
if (FALSE == was_crit)
rel_crit(p->region);
if (!retval)
{
INCR_GVSTATS_COUNTER(csa, csa->nl, n_lock_success, 1);
} else
{
INCR_GVSTATS_COUNTER(csa, csa->nl, n_lock_fail, 1);
}
} else /* acc_meth = dba_usr */
retval = gvusr_lock(p->total_length, &p->value[0], p->region);
return retval;
}