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bgworker.h File Reference
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Data Structures

struct  BackgroundWorker
 

Macros

#define BGWORKER_SHMEM_ACCESS   0x0001
 
#define BGWORKER_BACKEND_DATABASE_CONNECTION   0x0002
 
#define BGWORKER_CLASS_PARALLEL   0x0010
 
#define BGW_DEFAULT_RESTART_INTERVAL   60
 
#define BGW_NEVER_RESTART   -1
 
#define BGW_MAXLEN   96
 
#define BGW_EXTRALEN   128
 
#define BGWORKER_BYPASS_ALLOWCONN   1
 

Typedefs

typedef void(* bgworker_main_type) (Datum main_arg)
 
typedef struct BackgroundWorker BackgroundWorker
 
typedef enum BgwHandleStatus BgwHandleStatus
 
typedef struct BackgroundWorkerHandle BackgroundWorkerHandle
 

Enumerations

enum  BgWorkerStartTime { BgWorkerStart_PostmasterStart, BgWorkerStart_ConsistentState, BgWorkerStart_RecoveryFinished }
 
enum  BgwHandleStatus { BGWH_STARTED, BGWH_NOT_YET_STARTED, BGWH_STOPPED, BGWH_POSTMASTER_DIED }
 

Functions

void RegisterBackgroundWorker (BackgroundWorker *worker)
 
bool RegisterDynamicBackgroundWorker (BackgroundWorker *worker, BackgroundWorkerHandle **handle)
 
BgwHandleStatus GetBackgroundWorkerPid (BackgroundWorkerHandle *handle, pid_t *pidp)
 
BgwHandleStatus WaitForBackgroundWorkerStartup (BackgroundWorkerHandle *handle, pid_t *pid)
 
BgwHandleStatus WaitForBackgroundWorkerShutdown (BackgroundWorkerHandle *)
 
const char * GetBackgroundWorkerTypeByPid (pid_t pid)
 
void TerminateBackgroundWorker (BackgroundWorkerHandle *handle)
 
void BackgroundWorkerInitializeConnection (const char *dbname, const char *username, uint32 flags)
 
void BackgroundWorkerInitializeConnectionByOid (Oid dboid, Oid useroid, uint32 flags)
 
void BackgroundWorkerBlockSignals (void)
 
void BackgroundWorkerUnblockSignals (void)
 

Variables

PGDLLIMPORT BackgroundWorkerMyBgworkerEntry
 

Macro Definition Documentation

◆ BGW_DEFAULT_RESTART_INTERVAL

#define BGW_DEFAULT_RESTART_INTERVAL   60

Definition at line 83 of file bgworker.h.

◆ BGW_EXTRALEN

#define BGW_EXTRALEN   128

Definition at line 86 of file bgworker.h.

Referenced by BackgroundWorkerStateChange().

◆ BGW_MAXLEN

◆ BGW_NEVER_RESTART

◆ BGWORKER_BACKEND_DATABASE_CONNECTION

◆ BGWORKER_BYPASS_ALLOWCONN

#define BGWORKER_BYPASS_ALLOWCONN   1

◆ BGWORKER_CLASS_PARALLEL

◆ BGWORKER_SHMEM_ACCESS

Typedef Documentation

◆ BackgroundWorker

◆ BackgroundWorkerHandle

Definition at line 111 of file bgworker.h.

◆ BgwHandleStatus

◆ bgworker_main_type

typedef void(* bgworker_main_type) (Datum main_arg)

Definition at line 71 of file bgworker.h.

Enumeration Type Documentation

◆ BgwHandleStatus

Enumerator
BGWH_STARTED 
BGWH_NOT_YET_STARTED 
BGWH_STOPPED 
BGWH_POSTMASTER_DIED 

Definition at line 102 of file bgworker.h.

103 {
104  BGWH_STARTED, /* worker is running */
105  BGWH_NOT_YET_STARTED, /* worker hasn't been started yet */
106  BGWH_STOPPED, /* worker has exited */
107  BGWH_POSTMASTER_DIED /* postmaster died; worker status unclear */
BgwHandleStatus
Definition: bgworker.h:102

◆ BgWorkerStartTime

Enumerator
BgWorkerStart_PostmasterStart 
BgWorkerStart_ConsistentState 
BgWorkerStart_RecoveryFinished 

Definition at line 76 of file bgworker.h.

Function Documentation

◆ BackgroundWorkerBlockSignals()

void BackgroundWorkerBlockSignals ( void  )

Definition at line 5705 of file postmaster.c.

References BlockSig, and PG_SETMASK.

5706 {
5707  PG_SETMASK(&BlockSig);
5708 }
#define PG_SETMASK(mask)
Definition: pqsignal.h:19
sigset_t BlockSig
Definition: pqsignal.c:22

◆ BackgroundWorkerInitializeConnection()

void BackgroundWorkerInitializeConnection ( const char *  dbname,
const char *  username,
uint32  flags 
)

Definition at line 5659 of file postmaster.c.

References BackgroundWorker::bgw_flags, BGWORKER_BACKEND_DATABASE_CONNECTION, BGWORKER_BYPASS_ALLOWCONN, ereport, errcode(), errmsg(), ERROR, FATAL, InitPostgres(), InvalidOid, IsInitProcessingMode, MyBgworkerEntry, NormalProcessing, and SetProcessingMode.

Referenced by ApplyLauncherMain(), and initialize_worker_spi().

5660 {
5662 
5663  /* XXX is this the right errcode? */
5665  ereport(FATAL,
5666  (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
5667  errmsg("database connection requirement not indicated during registration")));
5668 
5670 
5671  /* it had better not gotten out of "init" mode yet */
5672  if (!IsInitProcessingMode())
5673  ereport(ERROR,
5674  (errmsg("invalid processing mode in background worker")));
5676 }
int errcode(int sqlerrcode)
Definition: elog.c:694
#define SetProcessingMode(mode)
Definition: miscadmin.h:400
BackgroundWorker * MyBgworkerEntry
Definition: postmaster.c:194
#define ERROR
Definition: elog.h:45
#define BGWORKER_BYPASS_ALLOWCONN
Definition: bgworker.h:154
#define FATAL
Definition: elog.h:54
const char * username
Definition: pgbench.c:246
#define InvalidOid
Definition: postgres_ext.h:36
#define ereport(elevel,...)
Definition: elog.h:155
void InitPostgres(const char *in_dbname, Oid dboid, const char *username, Oid useroid, char *out_dbname, bool override_allow_connections)
Definition: postinit.c:579
#define BGWORKER_BACKEND_DATABASE_CONNECTION
Definition: bgworker.h:59
char * dbname
Definition: streamutil.c:51
int errmsg(const char *fmt,...)
Definition: elog.c:905
#define IsInitProcessingMode()
Definition: miscadmin.h:395

◆ BackgroundWorkerInitializeConnectionByOid()

void BackgroundWorkerInitializeConnectionByOid ( Oid  dboid,
Oid  useroid,
uint32  flags 
)

Definition at line 5682 of file postmaster.c.

References BackgroundWorker::bgw_flags, BGWORKER_BACKEND_DATABASE_CONNECTION, BGWORKER_BYPASS_ALLOWCONN, ereport, errcode(), errmsg(), ERROR, FATAL, InitPostgres(), IsInitProcessingMode, MyBgworkerEntry, NormalProcessing, and SetProcessingMode.

Referenced by ApplyWorkerMain(), autoprewarm_database_main(), and ParallelWorkerMain().

5683 {
5685 
5686  /* XXX is this the right errcode? */
5688  ereport(FATAL,
5689  (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
5690  errmsg("database connection requirement not indicated during registration")));
5691 
5692  InitPostgres(NULL, dboid, NULL, useroid, NULL, (flags & BGWORKER_BYPASS_ALLOWCONN) != 0);
5693 
5694  /* it had better not gotten out of "init" mode yet */
5695  if (!IsInitProcessingMode())
5696  ereport(ERROR,
5697  (errmsg("invalid processing mode in background worker")));
5699 }
int errcode(int sqlerrcode)
Definition: elog.c:694
#define SetProcessingMode(mode)
Definition: miscadmin.h:400
BackgroundWorker * MyBgworkerEntry
Definition: postmaster.c:194
#define ERROR
Definition: elog.h:45
#define BGWORKER_BYPASS_ALLOWCONN
Definition: bgworker.h:154
#define FATAL
Definition: elog.h:54
#define ereport(elevel,...)
Definition: elog.h:155
void InitPostgres(const char *in_dbname, Oid dboid, const char *username, Oid useroid, char *out_dbname, bool override_allow_connections)
Definition: postinit.c:579
#define BGWORKER_BACKEND_DATABASE_CONNECTION
Definition: bgworker.h:59
int errmsg(const char *fmt,...)
Definition: elog.c:905
#define IsInitProcessingMode()
Definition: miscadmin.h:395

◆ BackgroundWorkerUnblockSignals()

void BackgroundWorkerUnblockSignals ( void  )

◆ GetBackgroundWorkerPid()

BgwHandleStatus GetBackgroundWorkerPid ( BackgroundWorkerHandle handle,
pid_t *  pidp 
)

Definition at line 1074 of file bgworker.c.

References Assert, BGWH_NOT_YET_STARTED, BGWH_STARTED, BGWH_STOPPED, BackgroundWorkerSlot::generation, BackgroundWorkerHandle::generation, BackgroundWorkerSlot::in_use, InvalidPid, LW_SHARED, LWLockAcquire(), LWLockRelease(), max_worker_processes, BackgroundWorkerSlot::pid, BackgroundWorkerArray::slot, and BackgroundWorkerHandle::slot.

Referenced by check_worker_status(), shm_mq_counterparty_gone(), shm_mq_wait_internal(), WaitForBackgroundWorkerShutdown(), WaitForBackgroundWorkerStartup(), WaitForParallelWorkersToAttach(), WaitForParallelWorkersToFinish(), and WaitForReplicationWorkerAttach().

1075 {
1076  BackgroundWorkerSlot *slot;
1077  pid_t pid;
1078 
1079  Assert(handle->slot < max_worker_processes);
1080  slot = &BackgroundWorkerData->slot[handle->slot];
1081 
1082  /*
1083  * We could probably arrange to synchronize access to data using memory
1084  * barriers only, but for now, let's just keep it simple and grab the
1085  * lock. It seems unlikely that there will be enough traffic here to
1086  * result in meaningful contention.
1087  */
1088  LWLockAcquire(BackgroundWorkerLock, LW_SHARED);
1089 
1090  /*
1091  * The generation number can't be concurrently changed while we hold the
1092  * lock. The pid, which is updated by the postmaster, can change at any
1093  * time, but we assume such changes are atomic. So the value we read
1094  * won't be garbage, but it might be out of date by the time the caller
1095  * examines it (but that's unavoidable anyway).
1096  *
1097  * The in_use flag could be in the process of changing from true to false,
1098  * but if it is already false then it can't change further.
1099  */
1100  if (handle->generation != slot->generation || !slot->in_use)
1101  pid = 0;
1102  else
1103  pid = slot->pid;
1104 
1105  /* All done. */
1106  LWLockRelease(BackgroundWorkerLock);
1107 
1108  if (pid == 0)
1109  return BGWH_STOPPED;
1110  else if (pid == InvalidPid)
1111  return BGWH_NOT_YET_STARTED;
1112  *pidp = pid;
1113  return BGWH_STARTED;
1114 }
static BackgroundWorkerArray * BackgroundWorkerData
Definition: bgworker.c:110
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1808
#define Assert(condition)
Definition: c.h:804
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1206
int max_worker_processes
Definition: globals.c:135
BackgroundWorkerSlot slot[FLEXIBLE_ARRAY_MEMBER]
Definition: bgworker.c:101
#define InvalidPid
Definition: miscadmin.h:32

◆ GetBackgroundWorkerTypeByPid()

const char* GetBackgroundWorkerTypeByPid ( pid_t  pid)

Definition at line 1288 of file bgworker.c.

References BGW_MAXLEN, BackgroundWorker::bgw_type, LW_SHARED, LWLockAcquire(), LWLockRelease(), BackgroundWorkerSlot::pid, BackgroundWorkerArray::slot, BackgroundWorkerArray::total_slots, and BackgroundWorkerSlot::worker.

Referenced by pg_stat_get_activity().

1289 {
1290  int slotno;
1291  bool found = false;
1292  static char result[BGW_MAXLEN];
1293 
1294  LWLockAcquire(BackgroundWorkerLock, LW_SHARED);
1295 
1296  for (slotno = 0; slotno < BackgroundWorkerData->total_slots; slotno++)
1297  {
1299 
1300  if (slot->pid > 0 && slot->pid == pid)
1301  {
1302  strcpy(result, slot->worker.bgw_type);
1303  found = true;
1304  break;
1305  }
1306  }
1307 
1308  LWLockRelease(BackgroundWorkerLock);
1309 
1310  if (!found)
1311  return NULL;
1312 
1313  return result;
1314 }
static BackgroundWorkerArray * BackgroundWorkerData
Definition: bgworker.c:110
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1808
BackgroundWorker worker
Definition: bgworker.c:82
#define BGW_MAXLEN
Definition: bgworker.h:85
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1206
char bgw_type[BGW_MAXLEN]
Definition: bgworker.h:91
BackgroundWorkerSlot slot[FLEXIBLE_ARRAY_MEMBER]
Definition: bgworker.c:101

◆ RegisterBackgroundWorker()

void RegisterBackgroundWorker ( BackgroundWorker worker)

Definition at line 878 of file bgworker.c.

References BackgroundWorker::bgw_library_name, BackgroundWorker::bgw_name, BackgroundWorker::bgw_notify_pid, DEBUG1, ereport, errcode(), errdetail_plural(), errhint(), errmsg(), errmsg_internal(), IsUnderPostmaster, LOG, malloc, max_worker_processes, process_shared_preload_libraries_in_progress, RegisteredBgWorker::rw_backend, RegisteredBgWorker::rw_child_slot, RegisteredBgWorker::rw_crashed_at, RegisteredBgWorker::rw_lnode, RegisteredBgWorker::rw_pid, RegisteredBgWorker::rw_terminate, RegisteredBgWorker::rw_worker, SanityCheckBackgroundWorker(), slist_push_head(), and BackgroundWorkerSlot::worker.

Referenced by _PG_init(), ApplyLauncherRegister(), and apw_start_leader_worker().

879 {
880  RegisteredBgWorker *rw;
881  static int numworkers = 0;
882 
883  if (!IsUnderPostmaster)
884  ereport(DEBUG1,
885  (errmsg_internal("registering background worker \"%s\"", worker->bgw_name)));
886 
888  strcmp(worker->bgw_library_name, "postgres") != 0)
889  {
890  if (!IsUnderPostmaster)
891  ereport(LOG,
892  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
893  errmsg("background worker \"%s\": must be registered in shared_preload_libraries",
894  worker->bgw_name)));
895  return;
896  }
897 
898  if (!SanityCheckBackgroundWorker(worker, LOG))
899  return;
900 
901  if (worker->bgw_notify_pid != 0)
902  {
903  ereport(LOG,
904  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
905  errmsg("background worker \"%s\": only dynamic background workers can request notification",
906  worker->bgw_name)));
907  return;
908  }
909 
910  /*
911  * Enforce maximum number of workers. Note this is overly restrictive: we
912  * could allow more non-shmem-connected workers, because these don't count
913  * towards the MAX_BACKENDS limit elsewhere. For now, it doesn't seem
914  * important to relax this restriction.
915  */
916  if (++numworkers > max_worker_processes)
917  {
918  ereport(LOG,
919  (errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
920  errmsg("too many background workers"),
921  errdetail_plural("Up to %d background worker can be registered with the current settings.",
922  "Up to %d background workers can be registered with the current settings.",
925  errhint("Consider increasing the configuration parameter \"max_worker_processes\".")));
926  return;
927  }
928 
929  /*
930  * Copy the registration data into the registered workers list.
931  */
932  rw = malloc(sizeof(RegisteredBgWorker));
933  if (rw == NULL)
934  {
935  ereport(LOG,
936  (errcode(ERRCODE_OUT_OF_MEMORY),
937  errmsg("out of memory")));
938  return;
939  }
940 
941  rw->rw_worker = *worker;
942  rw->rw_backend = NULL;
943  rw->rw_pid = 0;
944  rw->rw_child_slot = 0;
945  rw->rw_crashed_at = 0;
946  rw->rw_terminate = false;
947 
949 }
struct bkend * rw_backend
#define DEBUG1
Definition: elog.h:25
int errhint(const char *fmt,...)
Definition: elog.c:1152
bool process_shared_preload_libraries_in_progress
Definition: miscinit.c:1598
static void slist_push_head(slist_head *head, slist_node *node)
Definition: ilist.h:574
int errcode(int sqlerrcode)
Definition: elog.c:694
#define LOG
Definition: elog.h:26
#define malloc(a)
Definition: header.h:50
slist_head BackgroundWorkerList
Definition: bgworker.c:42
bool IsUnderPostmaster
Definition: globals.c:110
static bool SanityCheckBackgroundWorker(BackgroundWorker *worker, int elevel)
Definition: bgworker.c:641
#define ereport(elevel,...)
Definition: elog.h:155
int errmsg_internal(const char *fmt,...)
Definition: elog.c:992
char bgw_name[BGW_MAXLEN]
Definition: bgworker.h:90
int errdetail_plural(const char *fmt_singular, const char *fmt_plural, unsigned long n,...)
Definition: elog.c:1130
int errmsg(const char *fmt,...)
Definition: elog.c:905
pid_t bgw_notify_pid
Definition: bgworker.h:99
int max_worker_processes
Definition: globals.c:135
BackgroundWorker rw_worker
char bgw_library_name[BGW_MAXLEN]
Definition: bgworker.h:95

◆ RegisterDynamicBackgroundWorker()

bool RegisterDynamicBackgroundWorker ( BackgroundWorker worker,
BackgroundWorkerHandle **  handle 
)

Definition at line 962 of file bgworker.c.

References Assert, BackgroundWorker::bgw_flags, BGWORKER_CLASS_PARALLEL, ERROR, BackgroundWorkerSlot::generation, BackgroundWorkerSlot::in_use, InvalidPid, IsUnderPostmaster, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), MAX_PARALLEL_WORKER_LIMIT, max_parallel_workers, palloc(), BackgroundWorkerArray::parallel_register_count, BackgroundWorkerArray::parallel_terminate_count, pg_write_barrier, BackgroundWorkerSlot::pid, PMSIGNAL_BACKGROUND_WORKER_CHANGE, SanityCheckBackgroundWorker(), SendPostmasterSignal(), BackgroundWorkerArray::slot, success, BackgroundWorkerSlot::terminate, BackgroundWorkerArray::total_slots, and BackgroundWorkerSlot::worker.

Referenced by apw_start_database_worker(), apw_start_leader_worker(), LaunchParallelWorkers(), logicalrep_worker_launch(), setup_background_workers(), and worker_spi_launch().

964 {
965  int slotno;
966  bool success = false;
967  bool parallel;
968  uint64 generation = 0;
969 
970  /*
971  * We can't register dynamic background workers from the postmaster. If
972  * this is a standalone backend, we're the only process and can't start
973  * any more. In a multi-process environment, it might be theoretically
974  * possible, but we don't currently support it due to locking
975  * considerations; see comments on the BackgroundWorkerSlot data
976  * structure.
977  */
978  if (!IsUnderPostmaster)
979  return false;
980 
981  if (!SanityCheckBackgroundWorker(worker, ERROR))
982  return false;
983 
984  parallel = (worker->bgw_flags & BGWORKER_CLASS_PARALLEL) != 0;
985 
986  LWLockAcquire(BackgroundWorkerLock, LW_EXCLUSIVE);
987 
988  /*
989  * If this is a parallel worker, check whether there are already too many
990  * parallel workers; if so, don't register another one. Our view of
991  * parallel_terminate_count may be slightly stale, but that doesn't really
992  * matter: we would have gotten the same result if we'd arrived here
993  * slightly earlier anyway. There's no help for it, either, since the
994  * postmaster must not take locks; a memory barrier wouldn't guarantee
995  * anything useful.
996  */
1000  {
1004  LWLockRelease(BackgroundWorkerLock);
1005  return false;
1006  }
1007 
1008  /*
1009  * Look for an unused slot. If we find one, grab it.
1010  */
1011  for (slotno = 0; slotno < BackgroundWorkerData->total_slots; ++slotno)
1012  {
1014 
1015  if (!slot->in_use)
1016  {
1017  memcpy(&slot->worker, worker, sizeof(BackgroundWorker));
1018  slot->pid = InvalidPid; /* indicates not started yet */
1019  slot->generation++;
1020  slot->terminate = false;
1021  generation = slot->generation;
1022  if (parallel)
1024 
1025  /*
1026  * Make sure postmaster doesn't see the slot as in use before it
1027  * sees the new contents.
1028  */
1029  pg_write_barrier();
1030 
1031  slot->in_use = true;
1032  success = true;
1033  break;
1034  }
1035  }
1036 
1037  LWLockRelease(BackgroundWorkerLock);
1038 
1039  /* If we found a slot, tell the postmaster to notice the change. */
1040  if (success)
1042 
1043  /*
1044  * If we found a slot and the user has provided a handle, initialize it.
1045  */
1046  if (success && handle)
1047  {
1048  *handle = palloc(sizeof(BackgroundWorkerHandle));
1049  (*handle)->slot = slotno;
1050  (*handle)->generation = generation;
1051  }
1052 
1053  return success;
1054 }
int max_parallel_workers
Definition: globals.c:136
static BackgroundWorkerArray * BackgroundWorkerData
Definition: bgworker.c:110
#define BGWORKER_CLASS_PARALLEL
Definition: bgworker.h:67
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1808
#define ERROR
Definition: elog.h:45
uint32 parallel_register_count
Definition: bgworker.c:99
bool IsUnderPostmaster
Definition: globals.c:110
static bool SanityCheckBackgroundWorker(BackgroundWorker *worker, int elevel)
Definition: bgworker.c:641
#define Assert(condition)
Definition: c.h:804
BackgroundWorker worker
Definition: bgworker.c:82
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1206
void * palloc(Size size)
Definition: mcxt.c:950
uint32 parallel_terminate_count
Definition: bgworker.c:100
#define pg_write_barrier()
Definition: atomics.h:159
void SendPostmasterSignal(PMSignalReason reason)
Definition: pmsignal.c:153
#define MAX_PARALLEL_WORKER_LIMIT
BackgroundWorkerSlot slot[FLEXIBLE_ARRAY_MEMBER]
Definition: bgworker.c:101
static bool success
Definition: initdb.c:164
#define InvalidPid
Definition: miscadmin.h:32

◆ TerminateBackgroundWorker()

void TerminateBackgroundWorker ( BackgroundWorkerHandle handle)

Definition at line 1213 of file bgworker.c.

References Assert, BackgroundWorkerSlot::generation, BackgroundWorkerHandle::generation, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), max_worker_processes, PMSIGNAL_BACKGROUND_WORKER_CHANGE, SendPostmasterSignal(), BackgroundWorkerArray::slot, BackgroundWorkerHandle::slot, and BackgroundWorkerSlot::terminate.

Referenced by cleanup_background_workers(), and DestroyParallelContext().

1214 {
1215  BackgroundWorkerSlot *slot;
1216  bool signal_postmaster = false;
1217 
1218  Assert(handle->slot < max_worker_processes);
1219  slot = &BackgroundWorkerData->slot[handle->slot];
1220 
1221  /* Set terminate flag in shared memory, unless slot has been reused. */
1222  LWLockAcquire(BackgroundWorkerLock, LW_EXCLUSIVE);
1223  if (handle->generation == slot->generation)
1224  {
1225  slot->terminate = true;
1226  signal_postmaster = true;
1227  }
1228  LWLockRelease(BackgroundWorkerLock);
1229 
1230  /* Make sure the postmaster notices the change to shared memory. */
1231  if (signal_postmaster)
1233 }
static BackgroundWorkerArray * BackgroundWorkerData
Definition: bgworker.c:110
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1808
#define Assert(condition)
Definition: c.h:804
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1206
int max_worker_processes
Definition: globals.c:135
void SendPostmasterSignal(PMSignalReason reason)
Definition: pmsignal.c:153
BackgroundWorkerSlot slot[FLEXIBLE_ARRAY_MEMBER]
Definition: bgworker.c:101

◆ WaitForBackgroundWorkerShutdown()

BgwHandleStatus WaitForBackgroundWorkerShutdown ( BackgroundWorkerHandle )

Definition at line 1174 of file bgworker.c.

References BGWH_POSTMASTER_DIED, BGWH_STOPPED, CHECK_FOR_INTERRUPTS, GetBackgroundWorkerPid(), MyLatch, BackgroundWorkerSlot::pid, ResetLatch(), status(), WAIT_EVENT_BGWORKER_SHUTDOWN, WaitLatch(), WL_LATCH_SET, and WL_POSTMASTER_DEATH.

Referenced by apw_start_database_worker(), and WaitForParallelWorkersToExit().

1175 {
1177  int rc;
1178 
1179  for (;;)
1180  {
1181  pid_t pid;
1182 
1184 
1185  status = GetBackgroundWorkerPid(handle, &pid);
1186  if (status == BGWH_STOPPED)
1187  break;
1188 
1189  rc = WaitLatch(MyLatch,
1192 
1193  if (rc & WL_POSTMASTER_DEATH)
1194  {
1195  status = BGWH_POSTMASTER_DIED;
1196  break;
1197  }
1198 
1200  }
1201 
1202  return status;
1203 }
void ResetLatch(Latch *latch)
Definition: latch.c:660
int WaitLatch(Latch *latch, int wakeEvents, long timeout, uint32 wait_event_info)
Definition: latch.c:452
BgwHandleStatus
Definition: bgworker.h:102
#define WL_POSTMASTER_DEATH
Definition: latch.h:129
struct Latch * MyLatch
Definition: globals.c:55
#define CHECK_FOR_INTERRUPTS()
Definition: miscadmin.h:100
static void static void status(const char *fmt,...) pg_attribute_printf(1
Definition: pg_regress.c:227
#define WL_LATCH_SET
Definition: latch.h:125
BgwHandleStatus GetBackgroundWorkerPid(BackgroundWorkerHandle *handle, pid_t *pidp)
Definition: bgworker.c:1074

◆ WaitForBackgroundWorkerStartup()

BgwHandleStatus WaitForBackgroundWorkerStartup ( BackgroundWorkerHandle handle,
pid_t *  pid 
)

Definition at line 1129 of file bgworker.c.

References BGWH_NOT_YET_STARTED, BGWH_POSTMASTER_DIED, BGWH_STARTED, CHECK_FOR_INTERRUPTS, GetBackgroundWorkerPid(), MyLatch, BackgroundWorkerSlot::pid, ResetLatch(), status(), WAIT_EVENT_BGWORKER_STARTUP, WaitLatch(), WL_LATCH_SET, and WL_POSTMASTER_DEATH.

Referenced by apw_start_leader_worker(), and worker_spi_launch().

1130 {
1132  int rc;
1133 
1134  for (;;)
1135  {
1136  pid_t pid;
1137 
1139 
1140  status = GetBackgroundWorkerPid(handle, &pid);
1141  if (status == BGWH_STARTED)
1142  *pidp = pid;
1143  if (status != BGWH_NOT_YET_STARTED)
1144  break;
1145 
1146  rc = WaitLatch(MyLatch,
1149 
1150  if (rc & WL_POSTMASTER_DEATH)
1151  {
1152  status = BGWH_POSTMASTER_DIED;
1153  break;
1154  }
1155 
1157  }
1158 
1159  return status;
1160 }
void ResetLatch(Latch *latch)
Definition: latch.c:660
int WaitLatch(Latch *latch, int wakeEvents, long timeout, uint32 wait_event_info)
Definition: latch.c:452
BgwHandleStatus
Definition: bgworker.h:102
#define WL_POSTMASTER_DEATH
Definition: latch.h:129
struct Latch * MyLatch
Definition: globals.c:55
#define CHECK_FOR_INTERRUPTS()
Definition: miscadmin.h:100
static void static void status(const char *fmt,...) pg_attribute_printf(1
Definition: pg_regress.c:227
#define WL_LATCH_SET
Definition: latch.h:125
BgwHandleStatus GetBackgroundWorkerPid(BackgroundWorkerHandle *handle, pid_t *pidp)
Definition: bgworker.c:1074

Variable Documentation

◆ MyBgworkerEntry