/**************************************************************** * * * Copyright 2001, 2008 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 "tp_grab_crit.h" #include "deferred_signal_handler.h" #include "wcs_recover.h" #include "caller_id.h" #include "is_proc_alive.h" GBLREF short crash_count; GBLREF volatile int4 crit_count; GBLREF uint4 process_id; GBLREF node_local_ptr_t locknl; bool tp_grab_crit(gd_region *reg) { unix_db_info *udi; sgmnt_addrs *csa; enum cdb_sc status; mutex_spin_parms_ptr_t mutex_spin_parms; error_def(ERR_CRITRESET); error_def(ERR_DBCCERR); udi = FILE_INFO(reg); csa = &udi->s_addrs; if (!csa->now_crit) { assert(0 == crit_count); crit_count++; /* prevent interrupts */ DEBUG_ONLY(locknl = csa->nl;) /* for DEBUG_ONLY LOCK_HIST macro */ mutex_spin_parms = (mutex_spin_parms_ptr_t)&csa->hdr->mutex_spin_parms; status = mutex_lockwim(reg, mutex_spin_parms, crash_count); DEBUG_ONLY(locknl = NULL;) /* restore "locknl" to default value */ if (status != cdb_sc_normal) { crit_count = 0; switch (status) { case cdb_sc_nolock: return(FALSE); 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(FALSE); } /* There is only one case we know of when csa->nl->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 csa->nl->in_crit since it does not * hold crit at that point. But in that case, the pid reported in csa->nl->in_crit should be dead. Check that. */ assert((0 == csa->nl->in_crit) || (FALSE == is_proc_alive(csa->nl->in_crit, 0))); csa->nl->in_crit = process_id; CRIT_TRACE(crit_ops_gw); /* see gdsbt.h for comment on placement */ crit_count = 0; } /* Ideally we do not want to do wcs_recover if we are in interrupt code (as opposed to mainline code). * This is easily accomplished in VMS with a library function lib$ast_in_prog but in Unix there is no way * to tell mainline code from interrupt code without the caller providing that information. Hence we * currently do the cache recovery even in case of interrupt code even though it is a heavyweight operation. * If it is found to cause issues, this logic has to be re-examined. */ if (csa->hdr->wc_blocked) wcs_recover(reg); return(TRUE); }