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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 84 of file bgworker.h.

◆ BGW_EXTRALEN

#define BGW_EXTRALEN   128

Definition at line 87 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 112 of file bgworker.h.

◆ BgwHandleStatus

◆ bgworker_main_type

typedef void(* bgworker_main_type) (Datum main_arg)

Definition at line 72 of file bgworker.h.

Enumeration Type Documentation

◆ BgwHandleStatus

Enumerator
BGWH_STARTED 
BGWH_NOT_YET_STARTED 
BGWH_STOPPED 
BGWH_POSTMASTER_DIED 

Definition at line 103 of file bgworker.h.

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

◆ BgWorkerStartTime

Enumerator
BgWorkerStart_PostmasterStart 
BgWorkerStart_ConsistentState 
BgWorkerStart_RecoveryFinished 

Definition at line 77 of file bgworker.h.

Function Documentation

◆ BackgroundWorkerBlockSignals()

void BackgroundWorkerBlockSignals ( void  )

Definition at line 5775 of file postmaster.c.

References BlockSig, and PG_SETMASK.

5776 {
5777  PG_SETMASK(&BlockSig);
5778 }
#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 5729 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().

5730 {
5732 
5733  /* XXX is this the right errcode? */
5735  ereport(FATAL,
5736  (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
5737  errmsg("database connection requirement not indicated during registration")));
5738 
5740 
5741  /* it had better not gotten out of "init" mode yet */
5742  if (!IsInitProcessingMode())
5743  ereport(ERROR,
5744  (errmsg("invalid processing mode in background worker")));
5746 }
int errcode(int sqlerrcode)
Definition: elog.c:698
#define SetProcessingMode(mode)
Definition: miscadmin.h:412
BackgroundWorker * MyBgworkerEntry
Definition: postmaster.c:195
#define ERROR
Definition: elog.h:46
#define BGWORKER_BYPASS_ALLOWCONN
Definition: bgworker.h:155
#define FATAL
Definition: elog.h:49
const char * username
Definition: pgbench.c:282
#define InvalidOid
Definition: postgres_ext.h:36
#define ereport(elevel,...)
Definition: elog.h:157
void InitPostgres(const char *in_dbname, Oid dboid, const char *username, Oid useroid, char *out_dbname, bool override_allow_connections)
Definition: postinit.c:572
#define BGWORKER_BACKEND_DATABASE_CONNECTION
Definition: bgworker.h:60
char * dbname
Definition: streamutil.c:51
int errmsg(const char *fmt,...)
Definition: elog.c:909
#define IsInitProcessingMode()
Definition: miscadmin.h:407

◆ BackgroundWorkerInitializeConnectionByOid()

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

Definition at line 5752 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().

5753 {
5755 
5756  /* XXX is this the right errcode? */
5758  ereport(FATAL,
5759  (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
5760  errmsg("database connection requirement not indicated during registration")));
5761 
5762  InitPostgres(NULL, dboid, NULL, useroid, NULL, (flags & BGWORKER_BYPASS_ALLOWCONN) != 0);
5763 
5764  /* it had better not gotten out of "init" mode yet */
5765  if (!IsInitProcessingMode())
5766  ereport(ERROR,
5767  (errmsg("invalid processing mode in background worker")));
5769 }
int errcode(int sqlerrcode)
Definition: elog.c:698
#define SetProcessingMode(mode)
Definition: miscadmin.h:412
BackgroundWorker * MyBgworkerEntry
Definition: postmaster.c:195
#define ERROR
Definition: elog.h:46
#define BGWORKER_BYPASS_ALLOWCONN
Definition: bgworker.h:155
#define FATAL
Definition: elog.h:49
#define ereport(elevel,...)
Definition: elog.h:157
void InitPostgres(const char *in_dbname, Oid dboid, const char *username, Oid useroid, char *out_dbname, bool override_allow_connections)
Definition: postinit.c:572
#define BGWORKER_BACKEND_DATABASE_CONNECTION
Definition: bgworker.h:60
int errmsg(const char *fmt,...)
Definition: elog.c:909
#define IsInitProcessingMode()
Definition: miscadmin.h:407

◆ BackgroundWorkerUnblockSignals()

void BackgroundWorkerUnblockSignals ( void  )

◆ GetBackgroundWorkerPid()

BgwHandleStatus GetBackgroundWorkerPid ( BackgroundWorkerHandle handle,
pid_t *  pidp 
)

Definition at line 1068 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().

1069 {
1070  BackgroundWorkerSlot *slot;
1071  pid_t pid;
1072 
1073  Assert(handle->slot < max_worker_processes);
1074  slot = &BackgroundWorkerData->slot[handle->slot];
1075 
1076  /*
1077  * We could probably arrange to synchronize access to data using memory
1078  * barriers only, but for now, let's just keep it simple and grab the
1079  * lock. It seems unlikely that there will be enough traffic here to
1080  * result in meaningful contention.
1081  */
1082  LWLockAcquire(BackgroundWorkerLock, LW_SHARED);
1083 
1084  /*
1085  * The generation number can't be concurrently changed while we hold the
1086  * lock. The pid, which is updated by the postmaster, can change at any
1087  * time, but we assume such changes are atomic. So the value we read
1088  * won't be garbage, but it might be out of date by the time the caller
1089  * examines it (but that's unavoidable anyway).
1090  *
1091  * The in_use flag could be in the process of changing from true to false,
1092  * but if it is already false then it can't change further.
1093  */
1094  if (handle->generation != slot->generation || !slot->in_use)
1095  pid = 0;
1096  else
1097  pid = slot->pid;
1098 
1099  /* All done. */
1100  LWLockRelease(BackgroundWorkerLock);
1101 
1102  if (pid == 0)
1103  return BGWH_STOPPED;
1104  else if (pid == InvalidPid)
1105  return BGWH_NOT_YET_STARTED;
1106  *pidp = pid;
1107  return BGWH_STARTED;
1108 }
static BackgroundWorkerArray * BackgroundWorkerData
Definition: bgworker.c:110
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1803
#define Assert(condition)
Definition: c.h:804
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1199
int max_worker_processes
Definition: globals.c:137
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 1282 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().

1283 {
1284  int slotno;
1285  bool found = false;
1286  static char result[BGW_MAXLEN];
1287 
1288  LWLockAcquire(BackgroundWorkerLock, LW_SHARED);
1289 
1290  for (slotno = 0; slotno < BackgroundWorkerData->total_slots; slotno++)
1291  {
1293 
1294  if (slot->pid > 0 && slot->pid == pid)
1295  {
1296  strcpy(result, slot->worker.bgw_type);
1297  found = true;
1298  break;
1299  }
1300  }
1301 
1302  LWLockRelease(BackgroundWorkerLock);
1303 
1304  if (!found)
1305  return NULL;
1306 
1307  return result;
1308 }
static BackgroundWorkerArray * BackgroundWorkerData
Definition: bgworker.c:110
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1803
BackgroundWorker worker
Definition: bgworker.c:82
#define BGW_MAXLEN
Definition: bgworker.h:86
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1199
char bgw_type[BGW_MAXLEN]
Definition: bgworker.h:92
BackgroundWorkerSlot slot[FLEXIBLE_ARRAY_MEMBER]
Definition: bgworker.c:101

◆ RegisterBackgroundWorker()

void RegisterBackgroundWorker ( BackgroundWorker worker)

Definition at line 872 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().

873 {
874  RegisteredBgWorker *rw;
875  static int numworkers = 0;
876 
877  if (!IsUnderPostmaster)
878  ereport(DEBUG1,
879  (errmsg_internal("registering background worker \"%s\"", worker->bgw_name)));
880 
882  strcmp(worker->bgw_library_name, "postgres") != 0)
883  {
884  if (!IsUnderPostmaster)
885  ereport(LOG,
886  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
887  errmsg("background worker \"%s\": must be registered in shared_preload_libraries",
888  worker->bgw_name)));
889  return;
890  }
891 
892  if (!SanityCheckBackgroundWorker(worker, LOG))
893  return;
894 
895  if (worker->bgw_notify_pid != 0)
896  {
897  ereport(LOG,
898  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
899  errmsg("background worker \"%s\": only dynamic background workers can request notification",
900  worker->bgw_name)));
901  return;
902  }
903 
904  /*
905  * Enforce maximum number of workers. Note this is overly restrictive: we
906  * could allow more non-shmem-connected workers, because these don't count
907  * towards the MAX_BACKENDS limit elsewhere. For now, it doesn't seem
908  * important to relax this restriction.
909  */
910  if (++numworkers > max_worker_processes)
911  {
912  ereport(LOG,
913  (errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
914  errmsg("too many background workers"),
915  errdetail_plural("Up to %d background worker can be registered with the current settings.",
916  "Up to %d background workers can be registered with the current settings.",
919  errhint("Consider increasing the configuration parameter \"max_worker_processes\".")));
920  return;
921  }
922 
923  /*
924  * Copy the registration data into the registered workers list.
925  */
926  rw = malloc(sizeof(RegisteredBgWorker));
927  if (rw == NULL)
928  {
929  ereport(LOG,
930  (errcode(ERRCODE_OUT_OF_MEMORY),
931  errmsg("out of memory")));
932  return;
933  }
934 
935  rw->rw_worker = *worker;
936  rw->rw_backend = NULL;
937  rw->rw_pid = 0;
938  rw->rw_child_slot = 0;
939  rw->rw_crashed_at = 0;
940  rw->rw_terminate = false;
941 
943 }
struct bkend * rw_backend
#define DEBUG1
Definition: elog.h:25
int errhint(const char *fmt,...)
Definition: elog.c:1156
bool process_shared_preload_libraries_in_progress
Definition: miscinit.c:1615
static void slist_push_head(slist_head *head, slist_node *node)
Definition: ilist.h:593
int errcode(int sqlerrcode)
Definition: elog.c:698
#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:112
static bool SanityCheckBackgroundWorker(BackgroundWorker *worker, int elevel)
Definition: bgworker.c:652
#define ereport(elevel,...)
Definition: elog.h:157
int errmsg_internal(const char *fmt,...)
Definition: elog.c:996
char bgw_name[BGW_MAXLEN]
Definition: bgworker.h:91
int errdetail_plural(const char *fmt_singular, const char *fmt_plural, unsigned long n,...)
Definition: elog.c:1134
int errmsg(const char *fmt,...)
Definition: elog.c:909
pid_t bgw_notify_pid
Definition: bgworker.h:100
int max_worker_processes
Definition: globals.c:137
BackgroundWorker rw_worker
char bgw_library_name[BGW_MAXLEN]
Definition: bgworker.h:96

◆ RegisterDynamicBackgroundWorker()

bool RegisterDynamicBackgroundWorker ( BackgroundWorker worker,
BackgroundWorkerHandle **  handle 
)

Definition at line 956 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().

958 {
959  int slotno;
960  bool success = false;
961  bool parallel;
962  uint64 generation = 0;
963 
964  /*
965  * We can't register dynamic background workers from the postmaster. If
966  * this is a standalone backend, we're the only process and can't start
967  * any more. In a multi-process environment, it might be theoretically
968  * possible, but we don't currently support it due to locking
969  * considerations; see comments on the BackgroundWorkerSlot data
970  * structure.
971  */
972  if (!IsUnderPostmaster)
973  return false;
974 
975  if (!SanityCheckBackgroundWorker(worker, ERROR))
976  return false;
977 
978  parallel = (worker->bgw_flags & BGWORKER_CLASS_PARALLEL) != 0;
979 
980  LWLockAcquire(BackgroundWorkerLock, LW_EXCLUSIVE);
981 
982  /*
983  * If this is a parallel worker, check whether there are already too many
984  * parallel workers; if so, don't register another one. Our view of
985  * parallel_terminate_count may be slightly stale, but that doesn't really
986  * matter: we would have gotten the same result if we'd arrived here
987  * slightly earlier anyway. There's no help for it, either, since the
988  * postmaster must not take locks; a memory barrier wouldn't guarantee
989  * anything useful.
990  */
994  {
998  LWLockRelease(BackgroundWorkerLock);
999  return false;
1000  }
1001 
1002  /*
1003  * Look for an unused slot. If we find one, grab it.
1004  */
1005  for (slotno = 0; slotno < BackgroundWorkerData->total_slots; ++slotno)
1006  {
1008 
1009  if (!slot->in_use)
1010  {
1011  memcpy(&slot->worker, worker, sizeof(BackgroundWorker));
1012  slot->pid = InvalidPid; /* indicates not started yet */
1013  slot->generation++;
1014  slot->terminate = false;
1015  generation = slot->generation;
1016  if (parallel)
1018 
1019  /*
1020  * Make sure postmaster doesn't see the slot as in use before it
1021  * sees the new contents.
1022  */
1023  pg_write_barrier();
1024 
1025  slot->in_use = true;
1026  success = true;
1027  break;
1028  }
1029  }
1030 
1031  LWLockRelease(BackgroundWorkerLock);
1032 
1033  /* If we found a slot, tell the postmaster to notice the change. */
1034  if (success)
1036 
1037  /*
1038  * If we found a slot and the user has provided a handle, initialize it.
1039  */
1040  if (success && handle)
1041  {
1042  *handle = palloc(sizeof(BackgroundWorkerHandle));
1043  (*handle)->slot = slotno;
1044  (*handle)->generation = generation;
1045  }
1046 
1047  return success;
1048 }
int max_parallel_workers
Definition: globals.c:138
static BackgroundWorkerArray * BackgroundWorkerData
Definition: bgworker.c:110
#define BGWORKER_CLASS_PARALLEL
Definition: bgworker.h:68
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1803
#define ERROR
Definition: elog.h:46
uint32 parallel_register_count
Definition: bgworker.c:99
bool IsUnderPostmaster
Definition: globals.c:112
static bool SanityCheckBackgroundWorker(BackgroundWorker *worker, int elevel)
Definition: bgworker.c:652
#define Assert(condition)
Definition: c.h:804
BackgroundWorker worker
Definition: bgworker.c:82
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1199
void * palloc(Size size)
Definition: mcxt.c:1062
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:165
#define InvalidPid
Definition: miscadmin.h:32

◆ TerminateBackgroundWorker()

void TerminateBackgroundWorker ( BackgroundWorkerHandle handle)

Definition at line 1207 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().

1208 {
1209  BackgroundWorkerSlot *slot;
1210  bool signal_postmaster = false;
1211 
1212  Assert(handle->slot < max_worker_processes);
1213  slot = &BackgroundWorkerData->slot[handle->slot];
1214 
1215  /* Set terminate flag in shared memory, unless slot has been reused. */
1216  LWLockAcquire(BackgroundWorkerLock, LW_EXCLUSIVE);
1217  if (handle->generation == slot->generation)
1218  {
1219  slot->terminate = true;
1220  signal_postmaster = true;
1221  }
1222  LWLockRelease(BackgroundWorkerLock);
1223 
1224  /* Make sure the postmaster notices the change to shared memory. */
1225  if (signal_postmaster)
1227 }
static BackgroundWorkerArray * BackgroundWorkerData
Definition: bgworker.c:110
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1803
#define Assert(condition)
Definition: c.h:804
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1199
int max_worker_processes
Definition: globals.c:137
void SendPostmasterSignal(PMSignalReason reason)
Definition: pmsignal.c:153
BackgroundWorkerSlot slot[FLEXIBLE_ARRAY_MEMBER]
Definition: bgworker.c:101

◆ WaitForBackgroundWorkerShutdown()

BgwHandleStatus WaitForBackgroundWorkerShutdown ( BackgroundWorkerHandle )

Definition at line 1168 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().

1169 {
1171  int rc;
1172 
1173  for (;;)
1174  {
1175  pid_t pid;
1176 
1178 
1179  status = GetBackgroundWorkerPid(handle, &pid);
1180  if (status == BGWH_STOPPED)
1181  break;
1182 
1183  rc = WaitLatch(MyLatch,
1186 
1187  if (rc & WL_POSTMASTER_DEATH)
1188  {
1189  status = BGWH_POSTMASTER_DIED;
1190  break;
1191  }
1192 
1194  }
1195 
1196  return status;
1197 }
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:103
#define WL_POSTMASTER_DEATH
Definition: latch.h:129
struct Latch * MyLatch
Definition: globals.c:57
#define CHECK_FOR_INTERRUPTS()
Definition: miscadmin.h:120
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:1068

◆ WaitForBackgroundWorkerStartup()

BgwHandleStatus WaitForBackgroundWorkerStartup ( BackgroundWorkerHandle handle,
pid_t *  pid 
)

Definition at line 1123 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().

1124 {
1126  int rc;
1127 
1128  for (;;)
1129  {
1130  pid_t pid;
1131 
1133 
1134  status = GetBackgroundWorkerPid(handle, &pid);
1135  if (status == BGWH_STARTED)
1136  *pidp = pid;
1137  if (status != BGWH_NOT_YET_STARTED)
1138  break;
1139 
1140  rc = WaitLatch(MyLatch,
1143 
1144  if (rc & WL_POSTMASTER_DEATH)
1145  {
1146  status = BGWH_POSTMASTER_DIED;
1147  break;
1148  }
1149 
1151  }
1152 
1153  return status;
1154 }
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:103
#define WL_POSTMASTER_DEATH
Definition: latch.h:129
struct Latch * MyLatch
Definition: globals.c:57
#define CHECK_FOR_INTERRUPTS()
Definition: miscadmin.h:120
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:1068

Variable Documentation

◆ MyBgworkerEntry