int mur_forward_multi_proc(reg_ctl_list *rctl)
{
boolean_t multi_proc, this_reg_stuck, release_latch, ok_to_play;
boolean_t cancelled_dbsync_timer, cancelled_timer;
reg_ctl_list *rctl_top, *prev_rctl;
jnl_ctl_list *jctl;
gd_region *reg;
sgmnt_addrs *csa;
seq_num rec_token_seq;
jnl_tm_t rec_time;
enum broken_type recstat;
jnl_record *rec;
enum jnl_record_type rectype;
char errstr[256];
int i, rctl_index, save_errno, num_procs_stuck, num_reg_stuck;
uint4 status, regcnt_stuck, num_partners, start_hrtbt_cntr;
forw_multi_struct *forw_multi;
shm_forw_multi_t *sfm;
multi_struct *multi;
jnl_tm_t adjusted_resolve_time;
shm_reg_ctl_t *shm_rctl_start, *shm_rctl, *first_shm_rctl;
size_t shm_size, reccnt, copy_size;
int4 *size_ptr;
char *shmPtr; /* not using "shm_ptr" since it is already used in an AIX include file */
int shmid;
multi_proc_shm_hdr_t *mp_hdr; /* Pointer to "multi_proc_shm_hdr_t" structure in shared memory */
status = 0;
/* Although we made sure the # of tasks is the same as the # of processes forked off (in the "gtm_multi_proc"
* invocation in "mur_forward"), it is possible one of the forked process finishes one invocation of
* "mur_forward_multi_proc" before even another forked process gets assigned one task in "gtm_multi_proc_helper".
* In this case, we would be invoked more than once. But the first invocation would have done all the needed stuff
* so return for later invocations.
*/
if (mur_forward_multi_proc_done)
return 0;
mur_forward_multi_proc_done = TRUE;
/* Note: "rctl" is unused. But cannot avoid passing it since "gtm_multi_proc" expects something */
prev_rctl = NULL;
rctl_start = NULL;
adjusted_resolve_time = murgbl.adjusted_resolve_time;
assert(0 == murgbl.regcnt_remaining);
multi_proc = multi_proc_in_use; /* cache value in "local" to speed up access inside loops below */
if (multi_proc)
{
mp_hdr = multi_proc_shm_hdr;
shm_rctl_start = mur_shm_hdr->shm_rctl_start;
if (jgbl.onlnrlbk)
{
for (rctl = mur_ctl, rctl_top = mur_ctl + murgbl.reg_total; rctl < rctl_top; rctl++)
{
assert(rctl->csa->hold_onto_crit); /* would have been set in parent process */
rctl->csa->hold_onto_crit = FALSE; /* reset since we dont own this region */
assert(rctl->csa->now_crit); /* would have been set in parent process */
rctl->csa->now_crit = FALSE; /* reset since we dont own this region */
}
}
START_HEARTBEAT_IF_NEEDED; /* heartbeat timer needed later (in case not already started by "gtm_multi_proc") */
}
first_shm_rctl = NULL;
/* Phase1 of forward recovery starts */
for (rctl = mur_ctl, rctl_top = mur_ctl + murgbl.reg_total; rctl < rctl_top; rctl++)
{
/* Check if "rctl" is available for us or if some other concurrent process has taken it */
if (multi_proc)
{
rctl_index = rctl - &mur_ctl[0];
shm_rctl = &shm_rctl_start[rctl_index];
if (shm_rctl->owning_pid)
{
assert(process_id != shm_rctl->owning_pid);
continue;
}
GRAB_MULTI_PROC_LATCH_IF_NEEDED(release_latch);
assert(release_latch);
for ( ; rctl < rctl_top; rctl++, shm_rctl++)
{
if (shm_rctl->owning_pid)
{
assert(process_id != shm_rctl->owning_pid);
continue;
}
shm_rctl->owning_pid = process_id; /* Declare ownership */
rctl->this_pid_is_owner = TRUE;
if (jgbl.onlnrlbk)
{ /* This is an online rollback and crit was grabbed on all regions by the parent rollback
* process. But this child process now owns this region and does the actual rollback on
* this region so borrow crit for the duration of this child process.
*/
csa = rctl->csa;
csa->hold_onto_crit = TRUE;
csa->now_crit = TRUE;
assert(csa->nl->in_crit == mp_hdr->parent_pid);
csa->nl->in_crit = process_id;
assert(csa->nl->onln_rlbk_pid == mp_hdr->parent_pid);
csa->nl->onln_rlbk_pid = process_id;
}
if (NULL == first_shm_rctl)
first_shm_rctl = shm_rctl;
break;
}
REL_MULTI_PROC_LATCH_IF_NEEDED(release_latch);
if (rctl >= rctl_top)
{
assert(rctl == rctl_top);
break;
}
/* Set key to print this rctl'ss region-name as prefix in case this forked off process prints any output */
MUR_SET_MULTI_PROC_KEY(rctl, multi_proc_key);
# ifdef MUR_DEBUG
fprintf(stderr, "pid = %d : Owns region %s\n", process_id, multi_proc_key);
# endif
} else
rctl->this_pid_is_owner = TRUE;
if (mur_options.forward)
{
assert(NULL == rctl->jctl_turn_around);
jctl = rctl->jctl = rctl->jctl_head;
assert(jctl->reg_ctl == rctl);
jctl->rec_offset = JNL_HDR_LEN;
jnl_fence_ctl.fence_list = JNL_FENCE_LIST_END; /* initialized to reflect journaling is not enabled */
if (mur_options.rollback)
jgbl.mur_jrec_seqno = jctl->jfh->start_seqno;
} else
{
jctl = rctl->jctl = (NULL == rctl->jctl_turn_around) ? rctl->jctl_head : rctl->jctl_turn_around;
assert(jctl->reg_ctl == rctl);
jctl->rec_offset = jctl->turn_around_offset;
jgbl.mur_jrec_seqno = jctl->turn_around_seqno;
assert((NULL != rctl->jctl_turn_around) || (0 == jctl->rec_offset));
}
if (mur_options.rollback)
{
if (murgbl.consist_jnl_seqno < jgbl.mur_jrec_seqno)
{
/* Assert that murgbl.losttn_seqno is never lesser than jgbl.mur_jrec_seqno (the turnaround
* point seqno) as this is what murgbl.consist_jnl_seqno is going to be set to and will
* eventually be the post-rollback seqno. If this condition is violated, the result of the
* recovery is a compromised database (the file header will indicate a Region Seqno which
* is not necessarily correct since seqnos prior to it might be absent in the database).
* Therefore, this is an out-of-design situation with respect to rollback and so stop it.
*/
assert(murgbl.losttn_seqno >= jgbl.mur_jrec_seqno);
murgbl.consist_jnl_seqno = jgbl.mur_jrec_seqno;
}
assert(murgbl.consist_jnl_seqno <= murgbl.losttn_seqno);
}
if (mur_options.update || mur_options.extr[GOOD_TN])
{
reg = rctl->gd;
gv_cur_region = reg;
tp_change_reg(); /* note : sets cs_addrs to non-NULL value even if gv_cur_region->open is FALSE
* (cs_data could still be NULL). */
rctl->csa = cs_addrs;
cs_addrs->miscptr = (void *)rctl;
rctl->csd = cs_data;
rctl->sgm_info_ptr = cs_addrs->sgm_info_ptr;
assert(!reg->open || (NULL != cs_addrs->dir_tree));
gv_target = cs_addrs->dir_tree;
}
jctl->after_end_of_data = FALSE;
status = mur_next(jctl, jctl->rec_offset);
assert(ERR_JNLREADEOF != status); /* cannot get EOF at start of forward processing */
if (SS_NORMAL != status)
goto finish;
PRINT_VERBOSE_STAT(jctl, "mur_forward:at the start");
rctl->process_losttn = FALSE;
/* Any multi-region TP transaction will be processed as multiple single-region TP transactions up
* until the tp-resolve-time is reached. From then on, they will be treated as one multi-region TP
* transaction. This is needed for proper lost-tn determination (any multi-region transaction that
* gets played in a region AFTER it has already encountered a broken tn should treat this as a lost tn).
*/
do
{
if (multi_proc && IS_FORCED_MULTI_PROC_EXIT(mp_hdr))
{ /* We are at a logical point. So exit if signaled by parent */
status = ERR_FORCEDHALT;
goto finish;
}
assert(jctl == rctl->jctl);
rec = rctl->mur_desc->jnlrec;
rec_time = rec->prefix.time;
if (rec_time > mur_options.before_time)
break; /* Records after -BEFORE_TIME do not go to extract or losttrans or brkntrans files */
if (rec_time < mur_options.after_time)
{
status = mur_next_rec(&jctl);
continue; /* Records before -AFTER_TIME do not go to extract or losttrans or brkntrans files */
}
if (rec_time >= adjusted_resolve_time)
break; /* Records after this adjusted resolve_time will be processed below in phase2 */
/* Note: Since we do hashtable token processing only for records from tp_resolve_time onwards,
* it is possible that if we encounter any broken transactions here we wont know they are broken
* but will play them as is. That is unavoidable. Specify -SINCE_TIME (for -BACKWARD rollback/recover)
* and -VERIFY (for -FORWARD rollback/recover) to control tp_resolve_time (and in turn more
* effective broken tn determination).
*/
status = mur_forward_play_cur_jrec(rctl);
if (SS_NORMAL != status)
break;
status = mur_next_rec(&jctl);
} while (SS_NORMAL == status);
CHECK_IF_EOF_REACHED(rctl, status); /* sets rctl->forw_eof_seen if needed; resets "status" to SS_NORMAL */
if (SS_NORMAL != status)
{ /* ERR_FILENOTCREATE is possible from "mur_cre_file_extfmt" OR ERR_FORCEDHALT is possible
* from "mur_forward_play_cur_jrec". No other errors are known to occur here. Assert accordingly.
*/
assert((ERR_FILENOTCREATE == status) || (ERR_FORCEDHALT == status));
goto finish;
}
if (rctl->forw_eof_seen)
{
PRINT_VERBOSE_STAT(jctl, "mur_forward:Reached EOF before tp_resolve_time");
continue; /* Reached EOF before even getting to tp_resolve_time.
* Do not even consider region for next processing loop */
}
rctl->last_tn = 0;
murgbl.regcnt_remaining++; /* # of regions participating in recovery at this point */
if (NULL == rctl_start)
rctl_start = rctl;
if (NULL != prev_rctl)
{
prev_rctl->next_rctl = rctl;
rctl->prev_rctl = prev_rctl;
}
prev_rctl = rctl;
assert(murgbl.ok_to_update_db || !rctl->db_updated);
PRINT_VERBOSE_STAT(jctl, "mur_forward:at tp_resolve_time");
}
if (multi_proc)
multi_proc_key = NULL; /* reset key until it can be set to rctl's region-name again */
/* Note that it is possible for rctl_start to be NULL at this point. That is there is no journal record in any region
* AFTER the calculated tp-resolve-time. This is possible if for example -AFTER_TIME was used and has a time later
* than any journal record in all journal files. If rctl_start is NULL, prev_rctl should also be NULL and vice versa.
*/
if (NULL != rctl_start)
{
assert(NULL != prev_rctl);
prev_rctl->next_rctl = rctl_start;
rctl_start->prev_rctl = prev_rctl;
}
rctl = rctl_start;
regcnt_stuck = 0; /* # of regions we are stuck in waiting for other regions to resolve a multi-region TP transaction */
assert((NULL == rctl) || (NULL == rctl->forw_multi));
gv_cur_region = NULL; /* clear out any previous value to ensure gv_cur_region/cs_addrs/cs_data
* all get set in sync by the MUR_CHANGE_REG macro below.
*/
/* Phase2 of forward recovery starts */
while (NULL != rctl)
{ /* while there is at least one region remaining with unprocessed journal records */
assert(NULL != rctl_start);
assert(0 < murgbl.regcnt_remaining);
if (NULL != rctl->forw_multi)
{ /* This region's current journal record is part of a TP transaction waiting for other regions */
regcnt_stuck++;
assert(regcnt_stuck <= murgbl.regcnt_remaining);
if (regcnt_stuck == murgbl.regcnt_remaining)
{
assertpro(multi_proc_in_use); /* Else : Out-of-design situation. Stuck in ALL regions. */
/* Check one last time if all regions are stuck waiting for another process to resolve the
* multi-region TP transaction. If so, wait in a sleep loop. If not, we can proceed.
*/
rctl = rctl_start;
start_hrtbt_cntr = heartbeat_counter;
do
{
if (IS_FORCED_MULTI_PROC_EXIT(mp_hdr))
{ /* We are at a logical point. So exit if signaled by parent */
status = ERR_FORCEDHALT;
goto finish;
}
forw_multi = rctl->forw_multi;
assert(NULL != forw_multi);
sfm = forw_multi->shm_forw_multi;
assert(NULL != sfm);
assert(sfm->num_reg_seen_forward <= sfm->num_reg_seen_backward);
# ifdef MUR_DEBUG
fprintf(stderr, "Pid = %d : Line %d : token = %llu : forward = %d : backward = %d\n",
process_id, __LINE__, (long long int)sfm->token,
sfm->num_reg_seen_forward, sfm->num_reg_seen_backward);
# endif
if (sfm->num_reg_seen_forward == sfm->num_reg_seen_backward)
{ /* We are no longer stuck in this region */
assert(!forw_multi->no_longer_stuck);
forw_multi->no_longer_stuck = TRUE;
break;
}
rctl = rctl->next_rctl; /* Move on to the next available region */
assert(NULL != rctl);
if (rctl == rctl_start)
{ /* We went through all regions once and are still stuck.
* Sleep until at leat TWO heartbeats have elapsed after which check for deadlock.
* Do this only in the child process that owns the FIRST region in the region list.
* This way we dont have contention for the GRAB_MULTI_PROC_LATCH from
* all children at more or less the same time.
*/
if ((rctl == mur_ctl) && (heartbeat_counter > (start_hrtbt_cntr + 2)))
{ /* Check if all processes are stuck for a while. If so assertpro */
GRAB_MULTI_PROC_LATCH_IF_NEEDED(release_latch);
assert(release_latch);
shm_rctl_start = mur_shm_hdr->shm_rctl_start;
num_reg_stuck = 0;
for (i = 0; i < murgbl.reg_total; i++)
{
shm_rctl = &shm_rctl_start[i];
sfm = shm_rctl->shm_forw_multi;
if (NULL != sfm)
{
if (sfm->num_reg_seen_forward != sfm->num_reg_seen_backward)
num_reg_stuck++;
}
}
REL_MULTI_PROC_LATCH_IF_NEEDED(release_latch);
/* If everyone is stuck at this point, it is an out-of-design situation */
assertpro(num_reg_stuck < murgbl.reg_total);
start_hrtbt_cntr = heartbeat_counter;
} else
{ /* Sleep and recheck if any region we are stuck in got resolved.
* To minimize time spent sleeping, we just yield our timeslice.
*/
rel_quant();
continue;
}
}
} while (TRUE);
} else
{
rctl = rctl->next_rctl; /* Move on to the next available region */
assert(NULL != rctl);
continue;
}
}
regcnt_stuck = 0; /* restart the counter now that we found at least one non-stuck region */
MUR_CHANGE_REG(rctl);
jctl = rctl->jctl;
this_reg_stuck = FALSE;
for ( status = SS_NORMAL; SS_NORMAL == status; )
{
if (multi_proc && IS_FORCED_MULTI_PROC_EXIT(mp_hdr))
{ /* We are at a logical point. So exit if signaled by parent */
status = ERR_FORCEDHALT;
goto finish;
}
assert(jctl == rctl->jctl);
rec = rctl->mur_desc->jnlrec;
rec_time = rec->prefix.time;
if (rec_time > mur_options.before_time)
break; /* Records after -BEFORE_TIME do not go to extract or losttrans or brkntrans files */
assert((rec_time >= adjusted_resolve_time) || (mur_options.notncheck && !mur_options.verify));
assert((0 == mur_options.after_time) || (mur_options.forward && !rctl->db_updated));
if (rec_time < mur_options.after_time)
{
status = mur_next_rec(&jctl);
continue; /* Records before -AFTER_TIME do not go to extract or losttrans or brkntrans files */
}
/* Check if current journal record can be played right away or need to wait for corresponding journal
* records from other participating TP regions to be reached. A non-TP or ZTP transaction can be played
* without issues (i.e. has no dependencies with any other regions). A single-region TP transaction too
* falls in the same category. A multi-region TP transaction needs to wait until all participating regions
* have played all journal records BEFORE this TP in order to ensure recover plays records in the exact
* same order that GT.M performed them in.
*/
/* If FENCE_NONE is specified, we would not have maintained any multi hashtable in mur_back_process for
* broken transaction processing. So we process multi-region TP transactions as multiple single-region
* TP transactions in forward phase.
*/
if (FENCE_NONE != mur_options.fences)
{
rectype = (enum jnl_record_type)rec->prefix.jrec_type;
if (IS_TP(rectype) && IS_TUPD(rectype))
{
assert(IS_SET_KILL_ZKILL_ZTWORM_LGTRIG_ZTRIG(rectype));
assert(&rec->jrec_set_kill.num_participants == &rec->jrec_ztworm.num_participants);
assert(&rec->jrec_set_kill.num_participants == &rec->jrec_lgtrig.num_participants);
num_partners = rec->jrec_set_kill.num_participants;
assert(0 < num_partners);
if (1 < num_partners)
{
this_reg_stuck = TRUE;
assert(&rec->jrec_set_kill.update_num == &rec->jrec_ztworm.update_num);
assert(&rec->jrec_set_kill.update_num == &rec->jrec_lgtrig.update_num);
}
}
}
if (this_reg_stuck)
{
rec_token_seq = GET_JNL_SEQNO(rec);
MUR_FORW_TOKEN_LOOKUP(forw_multi, rec_token_seq, rec_time);
if (NULL != forw_multi)
{ /* This token has already been seen in another region in forward processing.
* Add current region as well. If all regions have been resolved, then play
* the entire transaction maintaining the exact same order of updates within.
*/
if (!forw_multi->no_longer_stuck)
MUR_FORW_TOKEN_ONE_MORE_REG(forw_multi, rctl);
} else
{ /* First time we are seeing this token in forward processing. Check if this
* has already been determined to be a broken transaction.
*/
recstat = GOOD_TN;
multi = NULL;
if (IS_REC_POSSIBLY_BROKEN(rec_time, rec_token_seq))
{
multi = MUR_TOKEN_LOOKUP(rec_token_seq, rec_time, TPFENCE);
if ((NULL != multi) && (0 < multi->partner))
recstat = BROKEN_TN;
}
MUR_FORW_TOKEN_ADD(forw_multi, rec_token_seq, rec_time, rctl, num_partners,
recstat, multi);
}
/* Check that "tabent" field has been initialized above (by either the MUR_FORW_TOKEN_LOOKUP
* or MUR_FORW_TOKEN_ADD macros). This is relied upon by "mur_forward_play_multireg_tp" below.
*/
assert(NULL != forw_multi->u.tabent);
assert(forw_multi->num_reg_seen_forward <= forw_multi->num_reg_seen_backward);
if (multi_proc)
{
sfm = forw_multi->shm_forw_multi;
ok_to_play = (NULL == sfm) || (sfm->num_reg_seen_forward == sfm->num_reg_seen_backward);
} else
ok_to_play = (forw_multi->num_reg_seen_forward == forw_multi->num_reg_seen_backward);
assert(ok_to_play || !forw_multi->no_longer_stuck);
if (ok_to_play )
{ /* We have enough information to proceed with playing this multi-region TP in
* forward processing (even if we might not have seen all needed regions). Now play it.
* Note that the TP could be BROKEN_TN or GOOD_TN. The callee handles it.
*/
assert(forw_multi == rctl->forw_multi);
status = mur_forward_play_multireg_tp(forw_multi, rctl);
this_reg_stuck = FALSE;
/* Note that as part of playing the TP transaction, we could have reached
* the EOF of rctl. In this case, we need to break out of the loop.
*/
if ((SS_NORMAL != status) || rctl->forw_eof_seen)
break;
assert(NULL == rctl->forw_multi);
assert(!dollar_tlevel);
jctl = rctl->jctl; /* In case the first record after the most recently processed
* TP transaction is in the next generation journal file */
continue;
}
break;
} else
{
status = mur_forward_play_cur_jrec(rctl);
if (SS_NORMAL != status)
break;
}
assert(!this_reg_stuck);
status = mur_next_rec(&jctl);
}
assert((NULL == rctl->forw_multi) || this_reg_stuck);
assert((NULL != rctl->forw_multi) || !this_reg_stuck);
if (!this_reg_stuck)
{ /* We are not stuck in this region (to resolve a multi-region TP).
* This means we are done processing all the records of this region.
*/
assert(NULL == rctl->forw_multi);
if (!rctl->forw_eof_seen)
{
CHECK_IF_EOF_REACHED(rctl, status);
/* sets rctl->forw_eof_seen if needed; resets "status" to SS_NORMAL */
if (SS_NORMAL != status)
{
assert(ERR_FILENOTCREATE == status);
goto finish;
}
assert(!dollar_tlevel);
DELETE_RCTL_FROM_UNPROCESSED_LIST(rctl); /* since all of its records should have been processed */
} else
{ /* EOF was seen in rctl inside "mur_forward_play_multireg_tp" and it was removed
* from the unprocessed list of rctls. At the time rctl was removed, its "next_rctl"
* field could have been pointing to another <rctl> that has since then also been
* removed inside the same function. Therefore the "next_rctl" field is not reliable
* in this case but instead we should rely on the global variable "rctl_start" which
* points to the list of unprocessed rctls. Set "next_rctl" accordingly.
*/
rctl->next_rctl = rctl_start;
if (ERR_JNLREADEOF == status)
status = SS_NORMAL;
}
assert(rctl->deleted_from_unprocessed_list);
}
assert(SS_NORMAL == status);
assert(!this_reg_stuck || !rctl->forw_eof_seen);
assert((NULL == rctl->next_rctl) || (NULL != rctl_start));
assert((NULL == rctl->next_rctl) || (0 < murgbl.regcnt_remaining));
rctl = rctl->next_rctl; /* Note : even though "rctl" could have been deleted from the doubly linked list above,
* rctl->next_rctl is not touched so we can still use it to get to the next element. */
}
assert(0 == murgbl.regcnt_remaining);
jgbl.mur_pini_addr_reset_fnptr = NULL; /* No more simulation of GT.M activity for any region */
prc_vec = murgbl.prc_vec; /* Use process-vector of MUPIP RECOVER (not any simulating GT.M process) now onwards */
assert(0 == dollar_tlevel);
for (rctl = mur_ctl, rctl_top = mur_ctl + murgbl.reg_total; rctl < rctl_top; rctl++)
{
if (!rctl->this_pid_is_owner)
{
assert(multi_proc_in_use);
continue; /* in a parallel processing environment, process only regions we own */
}
if (multi_proc)
{ /* Set key to print this rctl's region-name as prefix in case this forked off process prints any output */
MUR_SET_MULTI_PROC_KEY(rctl, multi_proc_key);
}
PRINT_VERBOSE_STAT(rctl->jctl, "mur_forward:at the end");
assert(!mur_options.rollback || (0 != murgbl.consist_jnl_seqno));
assert(mur_options.rollback || (0 == murgbl.consist_jnl_seqno));
assert(!dollar_tlevel); /* In case it applied a broken TUPD */
assert(murgbl.ok_to_update_db || !rctl->db_updated);
rctl->mur_plst = NULL; /* reset now that simulation of GT.M updates is done */
/* Ensure mur_block_count_correct is called if updates allowed */
if (murgbl.ok_to_update_db && (SS_NORMAL != mur_block_count_correct(rctl)))
{
gtm_putmsg_csa(CSA_ARG(rctl->csa) VARLSTCNT(4) ERR_BLKCNTEDITFAIL, 2, DB_LEN_STR(rctl->gd));
murgbl.wrn_count++;
}
}
finish:
if (multi_proc)
multi_proc_key = NULL; /* reset key until it can be set to rctl's region-name again */
if ((SS_NORMAL == status) && mur_options.show)
mur_output_show();
if (NULL != first_shm_rctl)
{ /* Transfer needed process-private information to shared memory so parent process can later inherit this. */
first_shm_rctl->err_cnt = murgbl.err_cnt;
first_shm_rctl->wrn_count = murgbl.wrn_count;
first_shm_rctl->consist_jnl_seqno = murgbl.consist_jnl_seqno;
/* If extract files were created by this process for one or more regions, then copy that information to
* shared memory so parent process can use this information to do a merge sort.
*/
shm_rctl = mur_shm_hdr->shm_rctl_start;
for (rctl = mur_ctl, rctl_top = mur_ctl + murgbl.reg_total; rctl < rctl_top; rctl++, shm_rctl++)
{
assert(multi_proc_in_use);
if (!rctl->this_pid_is_owner)
continue; /* in a parallel processing environment, process only regions we own */
/* Cancel any flush/dbsync timers by this child process for this region. This is because the
* child is not going to go through exit handling code (no gds_rundown etc.). And we need to
* clear up csa->nl->wcs_timers. (normally done by gds_rundown).
*/
if (NULL != rctl->csa) /* rctl->csa can be NULL in case of "mupip journal -extract" etc. */
CANCEL_DB_TIMERS(rctl->gd, rctl->csa, cancelled_timer, cancelled_dbsync_timer);
reccnt = 0;
for (size_ptr = &rctl->jnlext_multi_list_size[0], recstat = 0;
recstat < TOT_EXTR_TYPES;
recstat++, size_ptr++)
{ /* Assert "extr_file_created" information is in sync between rctl and shm_rctl.
* This was done at the end of "mur_cre_file_extfmt".
*/
assert(shm_rctl->extr_file_created[recstat] == rctl->extr_file_created[recstat]);
/* Assert that if *size_ptr is non-zero, then we better have created an extract file.
* Note that the converse is not true. It is possible we created a file for example to
* write an INCTN record but decided to not write anything because it was not a -detail
* type of extract. So *sizeptr could be 0 even though we created the extract file.
*/
assert(!*size_ptr || rctl->extr_file_created[recstat]);
shm_rctl->jnlext_list_size[recstat] = *size_ptr;
reccnt += *size_ptr;
}
assert(INVALID_SHMID == shm_rctl->jnlext_shmid);
shm_size = reccnt * SIZEOF(jnlext_multi_t);
/* If we are quitting because of an abnormal status OR a forced signal to terminate
* OR if the parent is dead (kill -9) dont bother creating shmid to communicate back with parent.
*/
if (mp_hdr->parent_pid != getppid())
{
SET_FORCED_MULTI_PROC_EXIT; /* Also signal sibling children to stop processing */
if (SS_NORMAL != status)
status = ERR_FORCEDHALT;
}
if ((SS_NORMAL == status) && shm_size)
{
shmid = shmget(IPC_PRIVATE, shm_size, 0600 | IPC_CREAT);
if (-1 == shmid)
{
save_errno = errno;
SNPRINTF(errstr, SIZEOF(errstr),
"shmget() : shmsize=0x%llx", shm_size);
MUR_SET_MULTI_PROC_KEY(rctl, multi_proc_key); /* to print region name prefix */
rts_error_csa(CSA_ARG(NULL) VARLSTCNT(8)
ERR_SYSCALL, 5, LEN_AND_STR(errstr), CALLFROM, save_errno);
}
shmPtr = (char *)do_shmat(shmid, 0, 0);
if (-1 == (sm_long_t)shmPtr)
{
save_errno = errno;
SNPRINTF(errstr, SIZEOF(errstr),
"shmat() : shmid=%d shmsize=0x%llx", shmid, shm_size);
MUR_SET_MULTI_PROC_KEY(rctl, multi_proc_key); /* to print region name prefix */
rts_error_csa(CSA_ARG(NULL) VARLSTCNT(8)
ERR_SYSCALL, 5, LEN_AND_STR(errstr), CALLFROM, save_errno);
}
shm_rctl->jnlext_shmid = shmid;
shm_rctl->jnlext_shm_size = shm_size;
for (size_ptr = &rctl->jnlext_multi_list_size[0], recstat = 0;
recstat < TOT_EXTR_TYPES;
recstat++, size_ptr++)
{
shm_size = *size_ptr;
if (shm_size)
{
copy_size = copy_list_to_buf(rctl->jnlext_multi_list[recstat],
(int4)shm_size, shmPtr);
assert(copy_size == (shm_size * SIZEOF(jnlext_multi_t)));
shmPtr += copy_size;
}
}
}
}
}
mur_close_file_extfmt(IN_MUR_CLOSE_FILES_FALSE); /* Need to flush buffered extract/losttrans/brokentrans files */
return (int)status;
}
uint4 mur_forward(jnl_tm_t min_broken_time, seq_num min_broken_seqno, seq_num losttn_seqno)
{
boolean_t added, this_reg_stuck;
boolean_t is_set_kill_zkill_ztworm, is_set_kill_zkill;
jnl_record *rec;
enum jnl_record_type rectype;
enum rec_fence_type rec_fence;
enum broken_type recstat;
jnl_tm_t rec_time;
int4 rec_image_count = 0; /* This is a dummy variable for UNIX */
uint4 status, regcnt_stuck, num_partners;
mval mv;
reg_ctl_list *rctl, *rctl_top, *prev_rctl;
jnl_ctl_list *jctl;
gd_region *reg;
sgmnt_addrs *csa;
seq_num rec_token_seq;
forw_multi_struct *forw_multi;
multi_struct *multi;
error_def(ERR_JNLREADEOF);
error_def(ERR_BLKCNTEDITFAIL);
skip_dbtriggers = TRUE; /* do not want to invoke any triggers for updates done by journal recovery */
murgbl.extr_buff = (char *)malloc(murgbl.max_extr_record_length);
for (recstat = (enum broken_type)0; recstat < TOT_EXTR_TYPES; recstat++)
murgbl.extr_file_create[recstat] = TRUE;
jgbl.dont_reset_gbl_jrec_time = jgbl.forw_phase_recovery = TRUE;
assert(NULL == jgbl.mur_pini_addr_reset_fnptr);
jgbl.mur_pini_addr_reset_fnptr = (pini_addr_reset_fnptr)mur_pini_addr_reset;
gv_keysize = DBKEYSIZE(MAX_KEY_SZ);
mu_gv_stack_init();
murgbl.consist_jnl_seqno = 0;
/* Note down passed in values in murgbl global so "mur_forward_play_cur_jrec" function can see it as well */
murgbl.min_broken_time = min_broken_time;
murgbl.min_broken_seqno = min_broken_seqno;
murgbl.losttn_seqno = losttn_seqno;
assert(!mur_options.rollback || (murgbl.losttn_seqno <= murgbl.min_broken_seqno));
prev_rctl = NULL;
rctl_start = NULL;
assert(0 == murgbl.regcnt_remaining);
for (rctl = mur_ctl, rctl_top = mur_ctl + murgbl.reg_total; rctl < rctl_top; rctl++)
{
if (mur_options.forward)
{
assert(NULL == rctl->jctl_turn_around);
jctl = rctl->jctl = rctl->jctl_head;
assert(jctl->reg_ctl == rctl);
jctl->rec_offset = JNL_HDR_LEN;
jnl_fence_ctl.fence_list = JNL_FENCE_LIST_END; /* initialized to reflect journaling is not enabled */
} else
{
jctl = rctl->jctl = (NULL == rctl->jctl_turn_around) ? rctl->jctl_head : rctl->jctl_turn_around;
assert(jctl->reg_ctl == rctl);
jctl->rec_offset = jctl->turn_around_offset;
jgbl.mur_jrec_seqno = jctl->turn_around_seqno;
if (mur_options.rollback && murgbl.consist_jnl_seqno < jgbl.mur_jrec_seqno)
murgbl.consist_jnl_seqno = jgbl.mur_jrec_seqno;
assert(murgbl.consist_jnl_seqno <= murgbl.losttn_seqno);
assert((NULL != rctl->jctl_turn_around) || (0 == jctl->rec_offset));
}
if (mur_options.update || mur_options.extr[GOOD_TN])
{
reg = rctl->gd;
gv_cur_region = reg;
tp_change_reg(); /* note : sets cs_addrs to non-NULL value even if gv_cur_region->open is FALSE
* (cs_data could still be NULL). */
rctl->csa = cs_addrs;
cs_addrs->rctl = rctl;
rctl->csd = cs_data;
rctl->sgm_info_ptr = cs_addrs->sgm_info_ptr;
SET_CSA_DIR_TREE(cs_addrs, MAX_KEY_SZ, reg);
gv_target = cs_addrs->dir_tree;
}
jctl->after_end_of_data = FALSE;
status = mur_next(jctl, jctl->rec_offset);
assert(ERR_JNLREADEOF != status); /* cannot get EOF at start of forward processing */
if (SS_NORMAL != status)
return status;
PRINT_VERBOSE_STAT(jctl, "mur_forward:at the start");
/* Any multi-region TP transaction will be processed as multiple single-region TP transactions up
* until the tp-resolve-time is reached. From then on, they will be treated as one multi-region TP
* transaction. This is needed for proper lost-tn determination (any multi-region transaction that
* gets played in a region AFTER it has already encountered a broken tn should treat this as a lost tn).
*/
do
{
assert(jctl == rctl->jctl);
rec = rctl->mur_desc->jnlrec;
rec_time = rec->prefix.time;
if (rec_time > mur_options.before_time)
break; /* Records after -BEFORE_TIME do not go to extract or losttrans or brkntrans files */
if (rec_time < mur_options.after_time)
{
status = mur_next_rec(&jctl);
continue; /* Records before -AFTER_TIME do not go to extract or losttrans or brkntrans files */
}
if (rec_time >= jgbl.mur_tp_resolve_time)
break; /* Records after tp-resolve-time will be processed below */
/* TODO: what do we do if we find a BROKEN tn here? */
status = mur_forward_play_cur_jrec(rctl);
if (SS_NORMAL != status)
break;
status = mur_next_rec(&jctl);
} while (SS_NORMAL == status);
CHECK_IF_EOF_REACHED(rctl, status); /* sets rctl->forw_eof_seen if needed; resets "status" to SS_NORMAL */
if (SS_NORMAL != status)
return status;
if (rctl->forw_eof_seen)
{
PRINT_VERBOSE_STAT(jctl, "mur_forward:Reached EOF before tp_resolve_time");
continue; /* Reached EOF before even getting to tp_resolve_time.
* Do not even consider region for next processing loop */
}
rctl->last_tn = 0;
rctl->process_losttn = FALSE;
murgbl.regcnt_remaining++; /* # of regions participating in recovery at this point */
if (NULL == rctl_start)
rctl_start = rctl;
if (NULL != prev_rctl)
{
prev_rctl->next_rctl = rctl;
rctl->prev_rctl = prev_rctl;
}
prev_rctl = rctl;
assert(murgbl.ok_to_update_db || !rctl->db_updated);
PRINT_VERBOSE_STAT(jctl, "mur_forward:at tp_resolve_time");
}
/* Note that it is possible for rctl_start to be NULL at this point. That is there is no journal record in any region
* AFTER the calculated tp-resolve-time. This is possible if for example -AFTER_TIME was used and has a time later
* than any journal record in all journal files. If rctl_start is NULL, prev_rctl should also be NULL and vice versa.
*/
if (prev_rctl != rctl_start)
{
assert(NULL != prev_rctl);
assert(NULL != rctl_start);
prev_rctl->next_rctl = rctl_start;
rctl_start->prev_rctl = prev_rctl;
} else
{ /* prev_rctl & rctl_start are identical. They both should be NULL or should point to a single element linked list */
assert((NULL == rctl_start) || (NULL == rctl_start->next_rctl) && (NULL == rctl_start->prev_rctl));
}
rctl = rctl_start;
regcnt_stuck = 0; /* # of regions we are stuck in waiting for other regions to resolve a multi-region TP transaction */
assert((NULL == rctl) || (NULL == rctl->forw_multi));
gv_cur_region = NULL; /* clear out any previous value to ensure gv_cur_region/cs_addrs/cs_data
* all get set in sync by the MUR_CHANGE_REG macro below.
*/
while (NULL != rctl)
{ /* while there is at least one region remaining with unprocessed journal records */
assert(NULL != rctl_start);
assert(0 < murgbl.regcnt_remaining);
if (NULL != rctl->forw_multi)
{ /* This region's current journal record is part of a TP transaction waiting for other regions */
regcnt_stuck++;
if (regcnt_stuck >= murgbl.regcnt_remaining)
GTMASSERT; /* Out-of-design situation. Stuck in ALL regions. */
rctl = rctl->next_rctl; /* Move on to the next available region */
assert(NULL != rctl);
continue;
}
regcnt_stuck = 0; /* restart the counter now that we found at least one non-stuck region */
MUR_CHANGE_REG(rctl);
jctl = rctl->jctl;
this_reg_stuck = FALSE;
for ( status = SS_NORMAL; SS_NORMAL == status; )
{
assert(jctl == rctl->jctl);
rec = rctl->mur_desc->jnlrec;
rec_time = rec->prefix.time;
assert(rec_time >= jgbl.mur_tp_resolve_time);
if (rec_time > mur_options.before_time)
break; /* Records after -BEFORE_TIME do not go to extract or losttrans or brkntrans files */
assert((0 == mur_options.after_time) || mur_options.forward && !rctl->db_updated);
if (rec_time < mur_options.after_time)
{
status = mur_next_rec(&jctl);
continue; /* Records before -AFTER_TIME do not go to extract or losttrans or brkntrans files */
}
/* Check if current journal record can be played right away or need to wait for corresponding journal
* records from other participating TP regions to be reached. A non-TP or ZTP transaction can be played
* without issues (i.e. has no dependencies with any other regions). A single-region TP transaction too
* falls in the same category. A multi-region TP transaction needs to wait until all participating regions
* have played all journal records BEFORE this TP in order to ensure recover plays records in the exact
* same order that GT.M performed them in.
*/
/* If FENCE_NONE is specified, we would not have maintained any multi hashtable in mur_back_process for
* broken transaction processing. So we process multi-region TP transactions as multiple single-region
* TP transactions in forward phase.
*/
if (FENCE_NONE != mur_options.fences)
{
rectype = (enum jnl_record_type)rec->prefix.jrec_type;
if (IS_TP(rectype) && IS_TUPD(rectype))
{
assert(IS_SET_KILL_ZKILL_ZTRIG_ZTWORM(rectype));
assert(&rec->jrec_set_kill.num_participants == &rec->jrec_ztworm.num_participants);
num_partners = rec->jrec_set_kill.num_participants;
assert(0 < num_partners);
if (1 < num_partners)
{
this_reg_stuck = TRUE;
assert(&rec->jrec_set_kill.update_num == &rec->jrec_ztworm.update_num);
}
}
}
if (this_reg_stuck)
{
rec_token_seq = GET_JNL_SEQNO(rec);
VMS_ONLY(
/* In VMS, pid is not unique. We need "image_count" as well. But this is not needed
* in case of rollback as the token is guaranteed to be unique in that case.
*/
if (!mur_options.rollback)
{
MUR_GET_IMAGE_COUNT(jctl, rec, rec_image_count, status);
if (SS_NORMAL != status)
{
this_reg_stuck = FALSE; /* so abnormal "status" gets checked below */
break;
}
}
)
/* In Unix, "rec_image_count" is ignored by the MUR_FORW* macros */
MUR_FORW_TOKEN_LOOKUP(forw_multi, rec_token_seq, rec_time, rec_image_count);
if (NULL != forw_multi)
{ /* This token has already been seen in another region in forward processing.
* Add current region as well. If all regions have been resolved, then play
* the entire transaction maintaining the exact same order of updates within.
*/
MUR_FORW_TOKEN_ONE_MORE_REG(forw_multi, rctl);
} else
{ /* First time we are seeing this token in forward processing. Check if this
* has already been determined to be a broken transaction.
*/
recstat = GOOD_TN;
multi = NULL;
if (IS_REC_POSSIBLY_BROKEN(rec_time, rec_token_seq))
{
multi = MUR_TOKEN_LOOKUP(rec_token_seq, rec_image_count, rec_time, TPFENCE);
if ((NULL != multi) && (0 < multi->partner))
recstat = BROKEN_TN;
}
MUR_FORW_TOKEN_ADD(forw_multi, rec_token_seq, rec_time, rctl, num_partners,
recstat, multi, rec_image_count);
}
/* Check that "tabent" field has been initialized above (by either the MUR_FORW_TOKEN_LOOKUP
* or MUR_FORW_TOKEN_ADD macros). This is relied upon by "mur_forward_play_multireg_tp" below.
*/
assert(NULL != forw_multi->u.tabent);
assert(forw_multi->num_reg_seen_forward <= forw_multi->num_reg_seen_backward);
if (forw_multi->num_reg_seen_forward == forw_multi->num_reg_seen_backward)
{ /* All regions have been seen in forward processing. Now play it.
* Note that the TP could be BROKEN_TN or GOOD_TN. The callee handles it.
*/
assert(forw_multi == rctl->forw_multi);
status = mur_forward_play_multireg_tp(forw_multi, rctl);
this_reg_stuck = FALSE;
/* Note that as part of playing the TP transaction, we could have reached
* the EOF of rctl. In this case, we need to break out of the loop.
*/
if ((SS_NORMAL != status) || rctl->forw_eof_seen)
break;
assert(NULL == rctl->forw_multi);
assert(!dollar_tlevel);
jctl = rctl->jctl; /* In case the first record after the most recently processed
* TP transaction is in the next generation journal file */
continue;
}
break;
} else
{
status = mur_forward_play_cur_jrec(rctl);
if (SS_NORMAL != status)
break;
}
assert(!this_reg_stuck);
status = mur_next_rec(&jctl);
}