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Data Structures | Macros | Typedefs | Enumerations | Functions | Variables
parallel.c File Reference
#include "postgres_fe.h"
#include <sys/select.h>
#include <sys/wait.h>
#include <signal.h>
#include <unistd.h>
#include <fcntl.h>
#include "fe_utils/string_utils.h"
#include "parallel.h"
#include "pg_backup_utils.h"
Include dependency graph for parallel.c:

Go to the source code of this file.

Data Structures

struct   ParallelSlot
 
struct   ShutdownInformation
 
struct   DumpSignalInformation
 

Macros

#define  PIPE_READ   0
 
#define  PIPE_WRITE   1
 
#define  NO_SLOT   (-1) /* Failure result for GetIdleWorker() */
 
#define  WORKER_IS_RUNNING(workerStatus)    ((workerStatus) == WRKR_IDLE || (workerStatus) == WRKR_WORKING)
 
#define  pgpipe(a)   pipe(a)
 
#define  piperead(a, b, c)   read(a,b,c)
 
#define  pipewrite(a, b, c)   write(a,b,c)
 
#define  write_stderr(str)
 
#define  messageStartsWith(msg, prefix)    (strncmp(msg, prefix, strlen(prefix)) == 0)
 

Typedefs

typedef struct ShutdownInformation  ShutdownInformation
 
typedef struct DumpSignalInformation  DumpSignalInformation
 

Enumerations

enum   T_WorkerStatus { WRKR_NOT_STARTED = 0 , WRKR_IDLE , WRKR_WORKING , WRKR_TERMINATED }
 

Functions

static ParallelSlot *  GetMyPSlot (ParallelState *pstate)
 
static void  archive_close_connection (int code, void *arg)
 
static void  ShutdownWorkersHard (ParallelState *pstate)
 
static void  WaitForTerminatingWorkers (ParallelState *pstate)
 
static void  set_cancel_handler (void)
 
static void  set_cancel_pstate (ParallelState *pstate)
 
static void  set_cancel_slot_archive (ParallelSlot *slot, ArchiveHandle *AH)
 
static void  RunWorker (ArchiveHandle *AH, ParallelSlot *slot)
 
static int  GetIdleWorker (ParallelState *pstate)
 
static bool  HasEveryWorkerTerminated (ParallelState *pstate)
 
static void  lockTableForWorker (ArchiveHandle *AH, TocEntry *te)
 
static void  WaitForCommands (ArchiveHandle *AH, int pipefd[2])
 
static bool  ListenToWorkers (ArchiveHandle *AH, ParallelState *pstate, bool do_wait)
 
static char *  getMessageFromLeader (int pipefd[2])
 
static void  sendMessageToLeader (int pipefd[2], const char *str)
 
static int  select_loop (int maxFd, fd_set *workerset)
 
static char *  getMessageFromWorker (ParallelState *pstate, bool do_wait, int *worker)
 
static void  sendMessageToWorker (ParallelState *pstate, int worker, const char *str)
 
static char *  readMessageFromPipe (int fd)
 
void  init_parallel_dump_utils (void)
 
void  on_exit_close_archive (Archive *AHX)
 
static void  sigTermHandler (SIGNAL_ARGS)
 
void  set_archive_cancel_info (ArchiveHandle *AH, PGconn *conn)
 
ParallelState *  ParallelBackupStart (ArchiveHandle *AH)
 
void  ParallelBackupEnd (ArchiveHandle *AH, ParallelState *pstate)
 
static void  buildWorkerCommand (ArchiveHandle *AH, TocEntry *te, T_Action act, char *buf, int buflen)
 
static void  parseWorkerCommand (ArchiveHandle *AH, TocEntry **te, T_Action *act, const char *msg)
 
static void  buildWorkerResponse (ArchiveHandle *AH, TocEntry *te, T_Action act, int status, char *buf, int buflen)
 
static int  parseWorkerResponse (ArchiveHandle *AH, TocEntry *te, const char *msg)
 
void  DispatchJobForTocEntry (ArchiveHandle *AH, ParallelState *pstate, TocEntry *te, T_Action act, ParallelCompletionPtr callback, void *callback_data)
 
bool  IsEveryWorkerIdle (ParallelState *pstate)
 
void  WaitForWorkers (ArchiveHandle *AH, ParallelState *pstate, WFW_WaitOption mode)
 

Variables

static ShutdownInformation  shutdown_info
 
static volatile DumpSignalInformation  signal_info
 

Macro Definition Documentation

◆ messageStartsWith

#define messageStartsWith (   msg,
  prefix 
)     (strncmp(msg, prefix, strlen(prefix)) == 0)

Definition at line 228 of file parallel.c.

◆ NO_SLOT

#define NO_SLOT   (-1) /* Failure result for GetIdleWorker() */

Definition at line 74 of file parallel.c.

◆ pgpipe

#define pgpipe (   a )    pipe(a)

Definition at line 139 of file parallel.c.

◆ PIPE_READ

#define PIPE_READ   0

Definition at line 71 of file parallel.c.

◆ PIPE_WRITE

#define PIPE_WRITE   1

Definition at line 72 of file parallel.c.

◆ piperead

#define piperead (   a,
  b,
  c 
)    read(a,b,c)

Definition at line 140 of file parallel.c.

◆ pipewrite

#define pipewrite (   a,
  b,
  c 
)    write(a,b,c)

Definition at line 141 of file parallel.c.

◆ WORKER_IS_RUNNING

#define WORKER_IS_RUNNING (   workerStatus )     ((workerStatus) == WRKR_IDLE || (workerStatus) == WRKR_WORKING)

Definition at line 85 of file parallel.c.

◆ write_stderr

#define write_stderr (   str )
Value:
do { \
const char *str_ = (str); \
int rc_; \
rc_ = write(fileno(stderr), str_, strlen(str_)); \
(void) rc_; \
} while (0)
const char * str
#define write(a, b, c)
Definition: win32.h:14

Definition at line 186 of file parallel.c.

Typedef Documentation

◆ DumpSignalInformation

typedef struct DumpSignalInformation DumpSignalInformation

◆ ShutdownInformation

typedef struct ShutdownInformation ShutdownInformation

Enumeration Type Documentation

◆ T_WorkerStatus

enum T_WorkerStatus
Enumerator
WRKR_NOT_STARTED 
WRKR_IDLE 
WRKR_WORKING 
WRKR_TERMINATED 

Definition at line 77 of file parallel.c.

78{
T_WorkerStatus
Definition: parallel.c:78
@ WRKR_WORKING
Definition: parallel.c:81
@ WRKR_IDLE
Definition: parallel.c:80
@ WRKR_TERMINATED
Definition: parallel.c:82
@ WRKR_NOT_STARTED
Definition: parallel.c:79

Function Documentation

◆ archive_close_connection()

static void archive_close_connection ( int  code,
void *  arg 
)
static

Definition at line 341 of file parallel.c.

342{
344
345 if (si->pstate)
346 {
347 /* In parallel mode, must figure out who we are */
348 ParallelSlot *slot = GetMyPSlot(si->pstate);
349
350 if (!slot)
351 {
352 /*
353 * We're the leader. Forcibly shut down workers, then close our
354 * own database connection, if any.
355 */
357
358 if (si->AHX)
360 }
361 else
362 {
363 /*
364 * We're a worker. Shut down our own DB connection if any. On
365 * Windows, we also have to close our communication sockets, to
366 * emulate what will happen on Unix when the worker process exits.
367 * (Without this, if this is a premature exit, the leader would
368 * fail to detect it because there would be no EOF condition on
369 * the other end of the pipe.)
370 */
371 if (slot->AH)
372 DisconnectDatabase(&(slot->AH->public));
373
374#ifdef WIN32
377#endif
378 }
379 }
380 else
381 {
382 /* Non-parallel operation: just kill the leader DB connection */
383 if (si->AHX)
385 }
386}
static ParallelSlot * GetMyPSlot(ParallelState *pstate)
Definition: parallel.c:266
static void ShutdownWorkersHard(ParallelState *pstate)
Definition: parallel.c:397
void DisconnectDatabase(Archive *AHX)
Definition: pg_backup_db.c:164
void * arg
#define closesocket
Definition: port.h:377
ArchiveHandle * AH
Definition: parallel.c:103
int pipeRevRead
Definition: parallel.c:107
int pipeRevWrite
Definition: parallel.c:108
Archive * AHX
Definition: parallel.c:151
ParallelState * pstate
Definition: parallel.c:150
Archive public

References ParallelSlot::AH, ShutdownInformation::AHX, arg, closesocket, DisconnectDatabase(), GetMyPSlot(), ParallelSlot::pipeRevRead, ParallelSlot::pipeRevWrite, ShutdownInformation::pstate, _archiveHandle::public, and ShutdownWorkersHard().

Referenced by on_exit_close_archive().

◆ buildWorkerCommand()

static void buildWorkerCommand ( ArchiveHandle *  AH,
TocEntry *  te,
T_Action  act,
char *  buf,
int  buflen 
)
static

Definition at line 1110 of file parallel.c.

1112{
1113 if (act == ACT_DUMP)
1114 snprintf(buf, buflen, "DUMP %d", te->dumpId);
1115 else if (act == ACT_RESTORE)
1116 snprintf(buf, buflen, "RESTORE %d", te->dumpId);
1117 else
1118 Assert(false);
1119}
Assert(PointerIsAligned(start, uint64))
@ ACT_RESTORE
@ ACT_DUMP
static char * buf
Definition: pg_test_fsync.c:72
#define snprintf
Definition: port.h:239
DumpId dumpId

References ACT_DUMP, ACT_RESTORE, Assert(), buf, _tocEntry::dumpId, and snprintf.

Referenced by DispatchJobForTocEntry().

◆ buildWorkerResponse()

static void buildWorkerResponse ( ArchiveHandle *  AH,
TocEntry *  te,
T_Action  act,
int  status,
char *  buf,
int  buflen 
)
static

Definition at line 1158 of file parallel.c.

1160{
1161 snprintf(buf, buflen, "OK %d %d %d",
1162 te->dumpId,
1163 status,
1164 status == WORKER_IGNORED_ERRORS ? AH->public.n_errors : 0);
1165}
#define WORKER_IGNORED_ERRORS
int n_errors
Definition: pg_backup.h:252

References buf, _tocEntry::dumpId, Archive::n_errors, _archiveHandle::public, snprintf, and WORKER_IGNORED_ERRORS.

Referenced by WaitForCommands().

◆ DispatchJobForTocEntry()

void DispatchJobForTocEntry ( ArchiveHandle *  AH,
ParallelState *  pstate,
TocEntry *  te,
T_Action  act,
ParallelCompletionPtr  callback,
void *  callback_data 
)

Definition at line 1207 of file parallel.c.

1213{
1214 int worker;
1215 char buf[256];
1216
1217 /* Get a worker, waiting if none are idle */
1218 while ((worker = GetIdleWorker(pstate)) == NO_SLOT)
1219 WaitForWorkers(AH, pstate, WFW_ONE_IDLE);
1220
1221 /* Construct and send command string */
1222 buildWorkerCommand(AH, te, act, buf, sizeof(buf));
1223
1224 sendMessageToWorker(pstate, worker, buf);
1225
1226 /* Remember worker is busy, and which TocEntry it's working on */
1227 pstate->parallelSlot[worker].workerStatus = WRKR_WORKING;
1228 pstate->parallelSlot[worker].callback = callback;
1229 pstate->parallelSlot[worker].callback_data = callback_data;
1230 pstate->te[worker] = te;
1231}
void WaitForWorkers(ArchiveHandle *AH, ParallelState *pstate, WFW_WaitOption mode)
Definition: parallel.c:1453
static int GetIdleWorker(ParallelState *pstate)
Definition: parallel.c:1238
static void buildWorkerCommand(ArchiveHandle *AH, TocEntry *te, T_Action act, char *buf, int buflen)
Definition: parallel.c:1110
#define NO_SLOT
Definition: parallel.c:74
static void sendMessageToWorker(ParallelState *pstate, int worker, const char *str)
Definition: parallel.c:1646
@ WFW_ONE_IDLE
Definition: parallel.h:34
ParallelCompletionPtr callback
Definition: parallel.c:100
void * callback_data
Definition: parallel.c:101
T_WorkerStatus workerStatus
Definition: parallel.c:97
TocEntry ** te
Definition: parallel.h:59
ParallelSlot * parallelSlot
Definition: parallel.h:60
static void callback(struct sockaddr *addr, struct sockaddr *mask, void *unused)
Definition: test_ifaddrs.c:46

References buf, buildWorkerCommand(), ParallelSlot::callback, callback(), ParallelSlot::callback_data, GetIdleWorker(), NO_SLOT, ParallelState::parallelSlot, sendMessageToWorker(), ParallelState::te, WaitForWorkers(), WFW_ONE_IDLE, ParallelSlot::workerStatus, and WRKR_WORKING.

Referenced by restore_toc_entries_parallel(), and WriteDataChunks().

◆ GetIdleWorker()

static int GetIdleWorker ( ParallelState *  pstate )
static

Definition at line 1238 of file parallel.c.

1239{
1240 int i;
1241
1242 for (i = 0; i < pstate->numWorkers; i++)
1243 {
1244 if (pstate->parallelSlot[i].workerStatus == WRKR_IDLE)
1245 return i;
1246 }
1247 return NO_SLOT;
1248}
i
int i
Definition: isn.c:77
int numWorkers
Definition: parallel.h:57

References i, NO_SLOT, ParallelState::numWorkers, ParallelState::parallelSlot, ParallelSlot::workerStatus, and WRKR_IDLE.

Referenced by DispatchJobForTocEntry(), and WaitForWorkers().

◆ getMessageFromLeader()

static char * getMessageFromLeader ( int  pipefd[2] )
static

Definition at line 1518 of file parallel.c.

1519{
1520 return readMessageFromPipe(pipefd[PIPE_READ]);
1521}
#define PIPE_READ
Definition: parallel.c:71
static char * readMessageFromPipe(int fd)
Definition: parallel.c:1664

References PIPE_READ, and readMessageFromPipe().

Referenced by WaitForCommands().

◆ getMessageFromWorker()

static char * getMessageFromWorker ( ParallelState *  pstate,
bool  do_wait,
int *  worker 
)
static

Definition at line 1581 of file parallel.c.

1582{
1583 int i;
1584 fd_set workerset;
1585 int maxFd = -1;
1586 struct timeval nowait = {0, 0};
1587
1588 /* construct bitmap of socket descriptors for select() */
1589 FD_ZERO(&workerset);
1590 for (i = 0; i < pstate->numWorkers; i++)
1591 {
1593 continue;
1594 FD_SET(pstate->parallelSlot[i].pipeRead, &workerset);
1595 if (pstate->parallelSlot[i].pipeRead > maxFd)
1596 maxFd = pstate->parallelSlot[i].pipeRead;
1597 }
1598
1599 if (do_wait)
1600 {
1601 i = select_loop(maxFd, &workerset);
1602 Assert(i != 0);
1603 }
1604 else
1605 {
1606 if ((i = select(maxFd + 1, &workerset, NULL, NULL, &nowait)) == 0)
1607 return NULL;
1608 }
1609
1610 if (i < 0)
1611 pg_fatal("%s() failed: %m", "select");
1612
1613 for (i = 0; i < pstate->numWorkers; i++)
1614 {
1615 char *msg;
1616
1618 continue;
1619 if (!FD_ISSET(pstate->parallelSlot[i].pipeRead, &workerset))
1620 continue;
1621
1622 /*
1623 * Read the message if any. If the socket is ready because of EOF,
1624 * we'll return NULL instead (and the socket will stay ready, so the
1625 * condition will persist).
1626 *
1627 * Note: because this is a blocking read, we'll wait if only part of
1628 * the message is available. Waiting a long time would be bad, but
1629 * since worker status messages are short and are always sent in one
1630 * operation, it shouldn't be a problem in practice.
1631 */
1633 *worker = i;
1634 return msg;
1635 }
1636 Assert(false);
1637 return NULL;
1638}
static int select_loop(int maxFd, fd_set *workerset)
Definition: parallel.c:1542
#define WORKER_IS_RUNNING(workerStatus)
Definition: parallel.c:85
#define pg_fatal(...)
static bool do_wait
Definition: pg_ctl.c:75
int pipeRead
Definition: parallel.c:105
#define select(n, r, w, e, timeout)
Definition: win32_port.h:503

References Assert(), do_wait, i, ParallelState::numWorkers, ParallelState::parallelSlot, pg_fatal, ParallelSlot::pipeRead, readMessageFromPipe(), select, select_loop(), WORKER_IS_RUNNING, and ParallelSlot::workerStatus.

Referenced by ListenToWorkers().

◆ GetMyPSlot()

static ParallelSlot * GetMyPSlot ( ParallelState *  pstate )
static

Definition at line 266 of file parallel.c.

267{
268 int i;
269
270 for (i = 0; i < pstate->numWorkers; i++)
271 {
272#ifdef WIN32
273 if (pstate->parallelSlot[i].threadId == GetCurrentThreadId())
274#else
275 if (pstate->parallelSlot[i].pid == getpid())
276#endif
277 return &(pstate->parallelSlot[i]);
278 }
279
280 return NULL;
281}
pid_t pid
Definition: parallel.c:115

References i, ParallelState::numWorkers, ParallelState::parallelSlot, and ParallelSlot::pid.

Referenced by archive_close_connection().

◆ HasEveryWorkerTerminated()

static bool HasEveryWorkerTerminated ( ParallelState *  pstate )
static

Definition at line 1254 of file parallel.c.

1255{
1256 int i;
1257
1258 for (i = 0; i < pstate->numWorkers; i++)
1259 {
1261 return false;
1262 }
1263 return true;
1264}

References i, ParallelState::numWorkers, ParallelState::parallelSlot, WORKER_IS_RUNNING, and ParallelSlot::workerStatus.

Referenced by WaitForTerminatingWorkers().

◆ init_parallel_dump_utils()

void init_parallel_dump_utils ( void  )

Definition at line 238 of file parallel.c.

239{
240#ifdef WIN32
241 if (!parallel_init_done)
242 {
243 WSADATA wsaData;
244 int err;
245
246 /* Prepare for threaded operation */
247 tls_index = TlsAlloc();
248 mainThreadId = GetCurrentThreadId();
249
250 /* Initialize socket access */
251 err = WSAStartup(MAKEWORD(2, 2), &wsaData);
252 if (err != 0)
253 pg_fatal("%s() failed: error code %d", "WSAStartup", err);
254
255 parallel_init_done = true;
256 }
257#endif
258}
void err(int eval, const char *fmt,...)
Definition: err.c:43

References err(), and pg_fatal.

Referenced by main().

◆ IsEveryWorkerIdle()

bool IsEveryWorkerIdle ( ParallelState *  pstate )

Definition at line 1270 of file parallel.c.

1271{
1272 int i;
1273
1274 for (i = 0; i < pstate->numWorkers; i++)
1275 {
1276 if (pstate->parallelSlot[i].workerStatus != WRKR_IDLE)
1277 return false;
1278 }
1279 return true;
1280}

References i, ParallelState::numWorkers, ParallelState::parallelSlot, ParallelSlot::workerStatus, and WRKR_IDLE.

Referenced by ParallelBackupEnd(), restore_toc_entries_parallel(), and WaitForWorkers().

◆ ListenToWorkers()

static bool ListenToWorkers ( ArchiveHandle *  AH,
ParallelState *  pstate,
bool  do_wait 
)
static

Definition at line 1400 of file parallel.c.

1401{
1402 int worker;
1403 char *msg;
1404
1405 /* Try to collect a status message */
1406 msg = getMessageFromWorker(pstate, do_wait, &worker);
1407
1408 if (!msg)
1409 {
1410 /* If do_wait is true, we must have detected EOF on some socket */
1411 if (do_wait)
1412 pg_fatal("a worker process died unexpectedly");
1413 return false;
1414 }
1415
1416 /* Process it and update our idea of the worker's status */
1417 if (messageStartsWith(msg, "OK "))
1418 {
1419 ParallelSlot *slot = &pstate->parallelSlot[worker];
1420 TocEntry *te = pstate->te[worker];
1421 int status;
1422
1423 status = parseWorkerResponse(AH, te, msg);
1424 slot->callback(AH, te, status, slot->callback_data);
1425 slot->workerStatus = WRKR_IDLE;
1426 pstate->te[worker] = NULL;
1427 }
1428 else
1429 pg_fatal("invalid message received from worker: \"%s\"",
1430 msg);
1431
1432 /* Free the string returned from getMessageFromWorker */
1433 free(msg);
1434
1435 return true;
1436}
static int parseWorkerResponse(ArchiveHandle *AH, TocEntry *te, const char *msg)
Definition: parallel.c:1173
static char * getMessageFromWorker(ParallelState *pstate, bool do_wait, int *worker)
Definition: parallel.c:1581
#define messageStartsWith(msg, prefix)
Definition: parallel.c:228
#define free(a)
Definition: header.h:65

References ParallelSlot::callback, ParallelSlot::callback_data, do_wait, free, getMessageFromWorker(), messageStartsWith, ParallelState::parallelSlot, parseWorkerResponse(), pg_fatal, ParallelState::te, ParallelSlot::workerStatus, and WRKR_IDLE.

Referenced by WaitForWorkers().

◆ lockTableForWorker()

static void lockTableForWorker ( ArchiveHandle *  AH,
TocEntry *  te 
)
static

Definition at line 1303 of file parallel.c.

1304{
1305 const char *qualId;
1306 PQExpBuffer query;
1307 PGresult *res;
1308
1309 /* Nothing to do for BLOBS */
1310 if (strcmp(te->desc, "BLOBS") == 0)
1311 return;
1312
1313 query = createPQExpBuffer();
1314
1315 qualId = fmtQualifiedId(te->namespace, te->tag);
1316
1317 appendPQExpBuffer(query, "LOCK TABLE %s IN ACCESS SHARE MODE NOWAIT",
1318 qualId);
1319
1320 res = PQexec(AH->connection, query->data);
1321
1322 if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
1323 pg_fatal("could not obtain lock on relation \"%s\"\n"
1324 "This usually means that someone requested an ACCESS EXCLUSIVE lock "
1325 "on the table after the pg_dump parent process had gotten the "
1326 "initial ACCESS SHARE lock on the table.", qualId);
1327
1328 PQclear(res);
1329 destroyPQExpBuffer(query);
1330}
PGresult * PQexec(PGconn *conn, const char *query)
Definition: fe-exec.c:2273
#define PQclear
Definition: libpq-be-fe.h:245
#define PQresultStatus
Definition: libpq-be-fe.h:247
@ PGRES_COMMAND_OK
Definition: libpq-fe.h:125
PQExpBuffer createPQExpBuffer(void)
Definition: pqexpbuffer.c:72
void appendPQExpBuffer(PQExpBuffer str, const char *fmt,...)
Definition: pqexpbuffer.c:265
void destroyPQExpBuffer(PQExpBuffer str)
Definition: pqexpbuffer.c:114
const char * fmtQualifiedId(const char *schema, const char *id)
Definition: string_utils.c:296
char * data
Definition: pqexpbuffer.h:46
PGconn * connection
char * tag
char * desc
Definition: libpq-int.h:165

References appendPQExpBuffer(), _archiveHandle::connection, createPQExpBuffer(), PQExpBufferData::data, _tocEntry::desc, destroyPQExpBuffer(), fmtQualifiedId(), pg_fatal, PGRES_COMMAND_OK, PQclear, PQexec(), PQresultStatus, and _tocEntry::tag.

Referenced by WaitForCommands().

◆ on_exit_close_archive()

void on_exit_close_archive ( Archive *  AHX )

Definition at line 330 of file parallel.c.

331{
332 shutdown_info.AHX = AHX;
334}
static void archive_close_connection(int code, void *arg)
Definition: parallel.c:341
static ShutdownInformation shutdown_info
Definition: parallel.c:154
void on_exit_nicely(on_exit_nicely_callback function, void *arg)

References ShutdownInformation::AHX, archive_close_connection(), on_exit_nicely(), and shutdown_info.

Referenced by main().

◆ ParallelBackupEnd()

void ParallelBackupEnd ( ArchiveHandle *  AH,
ParallelState *  pstate 
)

Definition at line 1061 of file parallel.c.

1062{
1063 int i;
1064
1065 /* No work if non-parallel */
1066 if (pstate->numWorkers == 1)
1067 return;
1068
1069 /* There should not be any unfinished jobs */
1070 Assert(IsEveryWorkerIdle(pstate));
1071
1072 /* Close the sockets so that the workers know they can exit */
1073 for (i = 0; i < pstate->numWorkers; i++)
1074 {
1077 }
1078
1079 /* Wait for them to exit */
1081
1082 /*
1083 * Unlink pstate from shutdown_info, so the exit handler will not try to
1084 * use it; and likewise unlink from signal_info.
1085 */
1086 shutdown_info.pstate = NULL;
1087 set_cancel_pstate(NULL);
1088
1089 /* Release state (mere neatnik-ism, since we're about to terminate) */
1090 free(pstate->te);
1091 free(pstate->parallelSlot);
1092 free(pstate);
1093}
static void set_cancel_pstate(ParallelState *pstate)
Definition: parallel.c:791
bool IsEveryWorkerIdle(ParallelState *pstate)
Definition: parallel.c:1270
static void WaitForTerminatingWorkers(ParallelState *pstate)
Definition: parallel.c:448
int pipeWrite
Definition: parallel.c:106

References Assert(), closesocket, free, i, IsEveryWorkerIdle(), ParallelState::numWorkers, ParallelState::parallelSlot, ParallelSlot::pipeRead, ParallelSlot::pipeWrite, ShutdownInformation::pstate, set_cancel_pstate(), shutdown_info, ParallelState::te, and WaitForTerminatingWorkers().

Referenced by _CloseArchive(), and RestoreArchive().

◆ ParallelBackupStart()

ParallelState * ParallelBackupStart ( ArchiveHandle *  AH )

Definition at line 899 of file parallel.c.

900{
901 ParallelState *pstate;
902 int i;
903
904 Assert(AH->public.numWorkers > 0);
905
906 pstate = (ParallelState *) pg_malloc(sizeof(ParallelState));
907
908 pstate->numWorkers = AH->public.numWorkers;
909 pstate->te = NULL;
910 pstate->parallelSlot = NULL;
911
912 if (AH->public.numWorkers == 1)
913 return pstate;
914
915 /* Create status arrays, being sure to initialize all fields to 0 */
916 pstate->te = (TocEntry **)
917 pg_malloc0(pstate->numWorkers * sizeof(TocEntry *));
918 pstate->parallelSlot = (ParallelSlot *)
919 pg_malloc0(pstate->numWorkers * sizeof(ParallelSlot));
920
921#ifdef WIN32
922 /* Make fmtId() and fmtQualifiedId() use thread-local storage */
923 getLocalPQExpBuffer = getThreadLocalPQExpBuffer;
924#endif
925
926 /*
927 * Set the pstate in shutdown_info, to tell the exit handler that it must
928 * clean up workers as well as the main database connection. But we don't
929 * set this in signal_info yet, because we don't want child processes to
930 * inherit non-NULL signal_info.pstate.
931 */
932 shutdown_info.pstate = pstate;
933
934 /*
935 * Temporarily disable query cancellation on the leader connection. This
936 * ensures that child processes won't inherit valid AH->connCancel
937 * settings and thus won't try to issue cancels against the leader's
938 * connection. No harm is done if we fail while it's disabled, because
939 * the leader connection is idle at this point anyway.
940 */
941 set_archive_cancel_info(AH, NULL);
942
943 /* Ensure stdio state is quiesced before forking */
944 fflush(NULL);
945
946 /* Create desired number of workers */
947 for (i = 0; i < pstate->numWorkers; i++)
948 {
949#ifdef WIN32
950 WorkerInfo *wi;
951 uintptr_t handle;
952#else
953 pid_t pid;
954#endif
955 ParallelSlot *slot = &(pstate->parallelSlot[i]);
956 int pipeMW[2],
957 pipeWM[2];
958
959 /* Create communication pipes for this worker */
960 if (pgpipe(pipeMW) < 0 || pgpipe(pipeWM) < 0)
961 pg_fatal("could not create communication channels: %m");
962
963 /* leader's ends of the pipes */
964 slot->pipeRead = pipeWM[PIPE_READ];
965 slot->pipeWrite = pipeMW[PIPE_WRITE];
966 /* child's ends of the pipes */
967 slot->pipeRevRead = pipeMW[PIPE_READ];
968 slot->pipeRevWrite = pipeWM[PIPE_WRITE];
969
970#ifdef WIN32
971 /* Create transient structure to pass args to worker function */
972 wi = (WorkerInfo *) pg_malloc(sizeof(WorkerInfo));
973
974 wi->AH = AH;
975 wi->slot = slot;
976
977 handle = _beginthreadex(NULL, 0, (void *) &init_spawned_worker_win32,
978 wi, 0, &(slot->threadId));
979 slot->hThread = handle;
980 slot->workerStatus = WRKR_IDLE;
981#else /* !WIN32 */
982 pid = fork();
983 if (pid == 0)
984 {
985 /* we are the worker */
986 int j;
987
988 /* this is needed for GetMyPSlot() */
989 slot->pid = getpid();
990
991 /* instruct signal handler that we're in a worker now */
992 signal_info.am_worker = true;
993
994 /* close read end of Worker -> Leader */
995 closesocket(pipeWM[PIPE_READ]);
996 /* close write end of Leader -> Worker */
997 closesocket(pipeMW[PIPE_WRITE]);
998
999 /*
1000 * Close all inherited fds for communication of the leader with
1001 * previously-forked workers.
1002 */
1003 for (j = 0; j < i; j++)
1004 {
1007 }
1008
1009 /* Run the worker ... */
1010 RunWorker(AH, slot);
1011
1012 /* We can just exit(0) when done */
1013 exit(0);
1014 }
1015 else if (pid < 0)
1016 {
1017 /* fork failed */
1018 pg_fatal("could not create worker process: %m");
1019 }
1020
1021 /* In Leader after successful fork */
1022 slot->pid = pid;
1023 slot->workerStatus = WRKR_IDLE;
1024
1025 /* close read end of Leader -> Worker */
1026 closesocket(pipeMW[PIPE_READ]);
1027 /* close write end of Worker -> Leader */
1028 closesocket(pipeWM[PIPE_WRITE]);
1029#endif /* WIN32 */
1030 }
1031
1032 /*
1033 * Having forked off the workers, disable SIGPIPE so that leader isn't
1034 * killed if it tries to send a command to a dead worker. We don't want
1035 * the workers to inherit this setting, though.
1036 */
1037#ifndef WIN32
1038 pqsignal(SIGPIPE, SIG_IGN);
1039#endif
1040
1041 /*
1042 * Re-establish query cancellation on the leader connection.
1043 */
1045
1046 /*
1047 * Tell the cancel signal handler to forward signals to worker processes,
1048 * too. (As with query cancel, we did not need this earlier because the
1049 * workers have not yet been given anything to do; if we die before this
1050 * point, any already-started workers will see EOF and quit promptly.)
1051 */
1052 set_cancel_pstate(pstate);
1053
1054 return pstate;
1055}
#define pgpipe(a)
Definition: parallel.c:139
static void RunWorker(ArchiveHandle *AH, ParallelSlot *slot)
Definition: parallel.c:831
#define PIPE_WRITE
Definition: parallel.c:72
static volatile DumpSignalInformation signal_info
Definition: parallel.c:175
void set_archive_cancel_info(ArchiveHandle *AH, PGconn *conn)
Definition: parallel.c:732
void * pg_malloc(size_t size)
Definition: fe_memutils.c:47
void * pg_malloc0(size_t size)
Definition: fe_memutils.c:53
j
int j
Definition: isn.c:78
#define pqsignal
Definition: port.h:531
PQExpBuffer(* getLocalPQExpBuffer)(void)
Definition: string_utils.c:28
int numWorkers
Definition: pg_backup.h:239
#define SIGPIPE
Definition: win32_port.h:163

References DumpSignalInformation::am_worker, Assert(), closesocket, _archiveHandle::connection, getLocalPQExpBuffer, i, j, ParallelState::numWorkers, Archive::numWorkers, ParallelState::parallelSlot, pg_fatal, pg_malloc(), pg_malloc0(), pgpipe, ParallelSlot::pid, PIPE_READ, PIPE_WRITE, ParallelSlot::pipeRead, ParallelSlot::pipeRevRead, ParallelSlot::pipeRevWrite, ParallelSlot::pipeWrite, pqsignal, ShutdownInformation::pstate, _archiveHandle::public, RunWorker(), set_archive_cancel_info(), set_cancel_pstate(), shutdown_info, signal_info, SIGPIPE, ParallelState::te, ParallelSlot::workerStatus, and WRKR_IDLE.

Referenced by _CloseArchive(), and RestoreArchive().

◆ parseWorkerCommand()

static void parseWorkerCommand ( ArchiveHandle *  AH,
TocEntry **  te,
T_Action *  act,
const char *  msg 
)
static

Definition at line 1125 of file parallel.c.

1127{
1128 DumpId dumpId;
1129 int nBytes;
1130
1131 if (messageStartsWith(msg, "DUMP "))
1132 {
1133 *act = ACT_DUMP;
1134 sscanf(msg, "DUMP %d%n", &dumpId, &nBytes);
1135 Assert(nBytes == strlen(msg));
1136 *te = getTocEntryByDumpId(AH, dumpId);
1137 Assert(*te != NULL);
1138 }
1139 else if (messageStartsWith(msg, "RESTORE "))
1140 {
1141 *act = ACT_RESTORE;
1142 sscanf(msg, "RESTORE %d%n", &dumpId, &nBytes);
1143 Assert(nBytes == strlen(msg));
1144 *te = getTocEntryByDumpId(AH, dumpId);
1145 Assert(*te != NULL);
1146 }
1147 else
1148 pg_fatal("unrecognized command received from leader: \"%s\"",
1149 msg);
1150}
int DumpId
Definition: pg_backup.h:284
TocEntry * getTocEntryByDumpId(ArchiveHandle *AH, DumpId id)

References ACT_DUMP, ACT_RESTORE, Assert(), getTocEntryByDumpId(), messageStartsWith, and pg_fatal.

Referenced by WaitForCommands().

◆ parseWorkerResponse()

static int parseWorkerResponse ( ArchiveHandle *  AH,
TocEntry *  te,
const char *  msg 
)
static

Definition at line 1173 of file parallel.c.

1175{
1176 DumpId dumpId;
1177 int nBytes,
1178 n_errors;
1179 int status = 0;
1180
1181 if (messageStartsWith(msg, "OK "))
1182 {
1183 sscanf(msg, "OK %d %d %d%n", &dumpId, &status, &n_errors, &nBytes);
1184
1185 Assert(dumpId == te->dumpId);
1186 Assert(nBytes == strlen(msg));
1187
1188 AH->public.n_errors += n_errors;
1189 }
1190 else
1191 pg_fatal("invalid message received from worker: \"%s\"",
1192 msg);
1193
1194 return status;
1195}

References Assert(), _tocEntry::dumpId, messageStartsWith, Archive::n_errors, pg_fatal, and _archiveHandle::public.

Referenced by ListenToWorkers().

◆ readMessageFromPipe()

static char * readMessageFromPipe ( int  fd )
static

Definition at line 1664 of file parallel.c.

1665{
1666 char *msg;
1667 int msgsize,
1668 bufsize;
1669 int ret;
1670
1671 /*
1672 * In theory, if we let piperead() read multiple bytes, it might give us
1673 * back fragments of multiple messages. (That can't actually occur, since
1674 * neither leader nor workers send more than one message without waiting
1675 * for a reply, but we don't wish to assume that here.) For simplicity,
1676 * read a byte at a time until we get the terminating '0円'. This method
1677 * is a bit inefficient, but since this is only used for relatively short
1678 * command and status strings, it shouldn't matter.
1679 */
1680 bufsize = 64; /* could be any number */
1681 msg = (char *) pg_malloc(bufsize);
1682 msgsize = 0;
1683 for (;;)
1684 {
1685 Assert(msgsize < bufsize);
1686 ret = piperead(fd, msg + msgsize, 1);
1687 if (ret <= 0)
1688 break; /* error or connection closure */
1689
1690 Assert(ret == 1);
1691
1692 if (msg[msgsize] == '0円')
1693 return msg; /* collected whole message */
1694
1695 msgsize++;
1696 if (msgsize == bufsize) /* enlarge buffer if needed */
1697 {
1698 bufsize += 16; /* could be any number */
1699 msg = (char *) pg_realloc(msg, bufsize);
1700 }
1701 }
1702
1703 /* Other end has closed the connection */
1704 pg_free(msg);
1705 return NULL;
1706}
#define piperead(a, b, c)
Definition: parallel.c:140
void pg_free(void *ptr)
Definition: fe_memutils.c:105
void * pg_realloc(void *ptr, size_t size)
Definition: fe_memutils.c:65
#define bufsize
Definition: indent_globs.h:36
static int fd(const char *x, int i)
Definition: preproc-init.c:105

References Assert(), bufsize, fd(), pg_free(), pg_malloc(), pg_realloc(), and piperead.

Referenced by getMessageFromLeader(), and getMessageFromWorker().

◆ RunWorker()

static void RunWorker ( ArchiveHandle *  AH,
ParallelSlot *  slot 
)
static

Definition at line 831 of file parallel.c.

832{
833 int pipefd[2];
834
835 /* fetch child ends of pipes */
836 pipefd[PIPE_READ] = slot->pipeRevRead;
837 pipefd[PIPE_WRITE] = slot->pipeRevWrite;
838
839 /*
840 * Clone the archive so that we have our own state to work with, and in
841 * particular our own database connection.
842 *
843 * We clone on Unix as well as Windows, even though technically we don't
844 * need to because fork() gives us a copy in our own address space
845 * already. But CloneArchive resets the state information and also clones
846 * the database connection which both seem kinda helpful.
847 */
848 AH = CloneArchive(AH);
849
850 /* Remember cloned archive where signal handler can find it */
851 set_cancel_slot_archive(slot, AH);
852
853 /*
854 * Call the setup worker function that's defined in the ArchiveHandle.
855 */
856 (AH->SetupWorkerPtr) ((Archive *) AH);
857
858 /*
859 * Execute commands until done.
860 */
861 WaitForCommands(AH, pipefd);
862
863 /*
864 * Disconnect from database and clean up.
865 */
866 set_cancel_slot_archive(slot, NULL);
868 DeCloneArchive(AH);
869}
static void WaitForCommands(ArchiveHandle *AH, int pipefd[2])
Definition: parallel.c:1338
static void set_cancel_slot_archive(ParallelSlot *slot, ArchiveHandle *AH)
Definition: parallel.c:811
void DeCloneArchive(ArchiveHandle *AH)
ArchiveHandle * CloneArchive(ArchiveHandle *AH)
SetupWorkerPtrType SetupWorkerPtr

References CloneArchive(), DeCloneArchive(), DisconnectDatabase(), PIPE_READ, PIPE_WRITE, ParallelSlot::pipeRevRead, ParallelSlot::pipeRevWrite, _archiveHandle::public, set_cancel_slot_archive(), _archiveHandle::SetupWorkerPtr, and WaitForCommands().

Referenced by ParallelBackupStart().

◆ select_loop()

static int select_loop ( int  maxFd,
fd_set *  workerset 
)
static

Definition at line 1542 of file parallel.c.

1543{
1544 int i;
1545 fd_set saveSet = *workerset;
1546
1547 for (;;)
1548 {
1549 *workerset = saveSet;
1550 i = select(maxFd + 1, workerset, NULL, NULL, NULL);
1551
1552#ifndef WIN32
1553 if (i < 0 && errno == EINTR)
1554 continue;
1555#else
1556 if (i == SOCKET_ERROR && WSAGetLastError() == WSAEINTR)
1557 continue;
1558#endif
1559 break;
1560 }
1561
1562 return i;
1563}
#define EINTR
Definition: win32_port.h:364

References EINTR, i, and select.

Referenced by getMessageFromWorker().

◆ sendMessageToLeader()

static void sendMessageToLeader ( int  pipefd[2],
const char *  str 
)
static

Definition at line 1529 of file parallel.c.

1530{
1531 int len = strlen(str) + 1;
1532
1533 if (pipewrite(pipefd[PIPE_WRITE], str, len) != len)
1534 pg_fatal("could not write to the communication channel: %m");
1535}
#define pipewrite(a, b, c)
Definition: parallel.c:141
const void size_t len

References len, pg_fatal, PIPE_WRITE, pipewrite, and str.

Referenced by WaitForCommands().

◆ sendMessageToWorker()

static void sendMessageToWorker ( ParallelState *  pstate,
int  worker,
const char *  str 
)
static

Definition at line 1646 of file parallel.c.

1647{
1648 int len = strlen(str) + 1;
1649
1650 if (pipewrite(pstate->parallelSlot[worker].pipeWrite, str, len) != len)
1651 {
1652 pg_fatal("could not write to the communication channel: %m");
1653 }
1654}

References len, ParallelState::parallelSlot, pg_fatal, ParallelSlot::pipeWrite, pipewrite, and str.

Referenced by DispatchJobForTocEntry().

◆ set_archive_cancel_info()

void set_archive_cancel_info ( ArchiveHandle *  AH,
PGconn *  conn 
)

Definition at line 732 of file parallel.c.

733{
734 PGcancel *oldConnCancel;
735
736 /*
737 * Activate the interrupt handler if we didn't yet in this process. On
738 * Windows, this also initializes signal_info_lock; therefore it's
739 * important that this happen at least once before we fork off any
740 * threads.
741 */
743
744 /*
745 * On Unix, we assume that storing a pointer value is atomic with respect
746 * to any possible signal interrupt. On Windows, use a critical section.
747 */
748
749#ifdef WIN32
750 EnterCriticalSection(&signal_info_lock);
751#endif
752
753 /* Free the old one if we have one */
754 oldConnCancel = AH->connCancel;
755 /* be sure interrupt handler doesn't use pointer while freeing */
756 AH->connCancel = NULL;
757
758 if (oldConnCancel != NULL)
759 PQfreeCancel(oldConnCancel);
760
761 /* Set the new one if specified */
762 if (conn)
764
765 /*
766 * On Unix, there's only ever one active ArchiveHandle per process, so we
767 * can just set signal_info.myAH unconditionally. On Windows, do that
768 * only in the main thread; worker threads have to make sure their
769 * ArchiveHandle appears in the pstate data, which is dealt with in
770 * RunWorker().
771 */
772#ifndef WIN32
773 signal_info.myAH = AH;
774#else
775 if (mainThreadId == GetCurrentThreadId())
776 signal_info.myAH = AH;
777#endif
778
779#ifdef WIN32
780 LeaveCriticalSection(&signal_info_lock);
781#endif
782}
static void set_cancel_handler(void)
Definition: parallel.c:610
PGcancel * PQgetCancel(PGconn *conn)
Definition: fe-cancel.c:368
void PQfreeCancel(PGcancel *cancel)
Definition: fe-cancel.c:502
PGconn * conn
Definition: streamutil.c:52
ArchiveHandle * myAH
Definition: parallel.c:167
PGcancel *volatile connCancel
Definition: fe-cancel.c:41

References conn, _archiveHandle::connCancel, DumpSignalInformation::myAH, PQfreeCancel(), PQgetCancel(), set_cancel_handler(), and signal_info.

Referenced by ConnectDatabaseAhx(), DisconnectDatabase(), and ParallelBackupStart().

◆ set_cancel_handler()

static void set_cancel_handler ( void  )
static

Definition at line 610 of file parallel.c.

611{
612 /*
613 * When forking, signal_info.handler_set will propagate into the new
614 * process, but that's fine because the signal handler state does too.
615 */
617 {
619
620 pqsignal(SIGINT, sigTermHandler);
621 pqsignal(SIGTERM, sigTermHandler);
623 }
624}
static void sigTermHandler(SIGNAL_ARGS)
Definition: parallel.c:547
#define SIGQUIT
Definition: win32_port.h:159

References DumpSignalInformation::handler_set, pqsignal, signal_info, SIGQUIT, and sigTermHandler().

Referenced by set_archive_cancel_info().

◆ set_cancel_pstate()

static void set_cancel_pstate ( ParallelState *  pstate )
static

Definition at line 791 of file parallel.c.

792{
793#ifdef WIN32
794 EnterCriticalSection(&signal_info_lock);
795#endif
796
797 signal_info.pstate = pstate;
798
799#ifdef WIN32
800 LeaveCriticalSection(&signal_info_lock);
801#endif
802}
ParallelState * pstate
Definition: parallel.c:168

References DumpSignalInformation::pstate, and signal_info.

Referenced by ParallelBackupEnd(), and ParallelBackupStart().

◆ set_cancel_slot_archive()

static void set_cancel_slot_archive ( ParallelSlot *  slot,
ArchiveHandle *  AH 
)
static

Definition at line 811 of file parallel.c.

812{
813#ifdef WIN32
814 EnterCriticalSection(&signal_info_lock);
815#endif
816
817 slot->AH = AH;
818
819#ifdef WIN32
820 LeaveCriticalSection(&signal_info_lock);
821#endif
822}

References ParallelSlot::AH.

Referenced by RunWorker().

◆ ShutdownWorkersHard()

static void ShutdownWorkersHard ( ParallelState *  pstate )
static

Definition at line 397 of file parallel.c.

398{
399 int i;
400
401 /*
402 * Close our write end of the sockets so that any workers waiting for
403 * commands know they can exit. (Note: some of the pipeWrite fields might
404 * still be zero, if we failed to initialize all the workers. Hence, just
405 * ignore errors here.)
406 */
407 for (i = 0; i < pstate->numWorkers; i++)
409
410 /*
411 * Force early termination of any commands currently in progress.
412 */
413#ifndef WIN32
414 /* On non-Windows, send SIGTERM to each worker process. */
415 for (i = 0; i < pstate->numWorkers; i++)
416 {
417 pid_t pid = pstate->parallelSlot[i].pid;
418
419 if (pid != 0)
420 kill(pid, SIGTERM);
421 }
422#else
423
424 /*
425 * On Windows, send query cancels directly to the workers' backends. Use
426 * a critical section to ensure worker threads don't change state.
427 */
428 EnterCriticalSection(&signal_info_lock);
429 for (i = 0; i < pstate->numWorkers; i++)
430 {
431 ArchiveHandle *AH = pstate->parallelSlot[i].AH;
432 char errbuf[1];
433
434 if (AH != NULL && AH->connCancel != NULL)
435 (void) PQcancel(AH->connCancel, errbuf, sizeof(errbuf));
436 }
437 LeaveCriticalSection(&signal_info_lock);
438#endif
439
440 /* Now wait for them to terminate. */
442}
int PQcancel(PGcancel *cancel, char *errbuf, int errbufsize)
Definition: fe-cancel.c:548
#define kill(pid, sig)
Definition: win32_port.h:493

References ParallelSlot::AH, closesocket, _archiveHandle::connCancel, i, kill, ParallelState::numWorkers, ParallelState::parallelSlot, ParallelSlot::pid, ParallelSlot::pipeWrite, PQcancel(), and WaitForTerminatingWorkers().

Referenced by archive_close_connection().

◆ sigTermHandler()

static void sigTermHandler ( SIGNAL_ARGS  )
static

Definition at line 547 of file parallel.c.

548{
549 int i;
550 char errbuf[1];
551
552 /*
553 * Some platforms allow delivery of new signals to interrupt an active
554 * signal handler. That could muck up our attempt to send PQcancel, so
555 * disable the signals that set_cancel_handler enabled.
556 */
557 pqsignal(SIGINT, SIG_IGN);
558 pqsignal(SIGTERM, SIG_IGN);
559 pqsignal(SIGQUIT, SIG_IGN);
560
561 /*
562 * If we're in the leader, forward signal to all workers. (It seems best
563 * to do this before PQcancel; killing the leader transaction will result
564 * in invalid-snapshot errors from active workers, which maybe we can
565 * quiet by killing workers first.) Ignore any errors.
566 */
567 if (signal_info.pstate != NULL)
568 {
569 for (i = 0; i < signal_info.pstate->numWorkers; i++)
570 {
571 pid_t pid = signal_info.pstate->parallelSlot[i].pid;
572
573 if (pid != 0)
574 kill(pid, SIGTERM);
575 }
576 }
577
578 /*
579 * Send QueryCancel if we have a connection to send to. Ignore errors,
580 * there's not much we can do about them anyway.
581 */
582 if (signal_info.myAH != NULL && signal_info.myAH->connCancel != NULL)
583 (void) PQcancel(signal_info.myAH->connCancel, errbuf, sizeof(errbuf));
584
585 /*
586 * Report we're quitting, using nothing more complicated than write(2).
587 * When in parallel operation, only the leader process should do this.
588 */
590 {
591 if (progname)
592 {
594 write_stderr(": ");
595 }
596 write_stderr("terminated by user\n");
597 }
598
599 /*
600 * And die, using _exit() not exit() because the latter will invoke atexit
601 * handlers that can fail if we interrupted related code.
602 */
603 _exit(1);
604}
#define write_stderr(str)
Definition: parallel.c:186
const char * progname
Definition: main.c:44

References DumpSignalInformation::am_worker, _archiveHandle::connCancel, i, kill, DumpSignalInformation::myAH, ParallelState::numWorkers, ParallelState::parallelSlot, ParallelSlot::pid, PQcancel(), pqsignal, progname, DumpSignalInformation::pstate, signal_info, SIGQUIT, and write_stderr.

Referenced by set_cancel_handler().

◆ WaitForCommands()

static void WaitForCommands ( ArchiveHandle *  AH,
int  pipefd[2] 
)
static

Definition at line 1338 of file parallel.c.

1339{
1340 char *command;
1341 TocEntry *te;
1342 T_Action act;
1343 int status = 0;
1344 char buf[256];
1345
1346 for (;;)
1347 {
1348 if (!(command = getMessageFromLeader(pipefd)))
1349 {
1350 /* EOF, so done */
1351 return;
1352 }
1353
1354 /* Decode the command */
1355 parseWorkerCommand(AH, &te, &act, command);
1356
1357 if (act == ACT_DUMP)
1358 {
1359 /* Acquire lock on this table within the worker's session */
1360 lockTableForWorker(AH, te);
1361
1362 /* Perform the dump command */
1363 status = (AH->WorkerJobDumpPtr) (AH, te);
1364 }
1365 else if (act == ACT_RESTORE)
1366 {
1367 /* Perform the restore command */
1368 status = (AH->WorkerJobRestorePtr) (AH, te);
1369 }
1370 else
1371 Assert(false);
1372
1373 /* Return status to leader */
1374 buildWorkerResponse(AH, te, act, status, buf, sizeof(buf));
1375
1376 sendMessageToLeader(pipefd, buf);
1377
1378 /* command was pg_malloc'd and we are responsible for free()ing it. */
1379 free(command);
1380 }
1381}
static void sendMessageToLeader(int pipefd[2], const char *str)
Definition: parallel.c:1529
static char * getMessageFromLeader(int pipefd[2])
Definition: parallel.c:1518
static void lockTableForWorker(ArchiveHandle *AH, TocEntry *te)
Definition: parallel.c:1303
static void buildWorkerResponse(ArchiveHandle *AH, TocEntry *te, T_Action act, int status, char *buf, int buflen)
Definition: parallel.c:1158
static void parseWorkerCommand(ArchiveHandle *AH, TocEntry **te, T_Action *act, const char *msg)
Definition: parallel.c:1125
T_Action
WorkerJobDumpPtrType WorkerJobDumpPtr
WorkerJobRestorePtrType WorkerJobRestorePtr

References ACT_DUMP, ACT_RESTORE, Assert(), buf, buildWorkerResponse(), free, getMessageFromLeader(), lockTableForWorker(), parseWorkerCommand(), sendMessageToLeader(), _archiveHandle::WorkerJobDumpPtr, and _archiveHandle::WorkerJobRestorePtr.

Referenced by RunWorker().

◆ WaitForTerminatingWorkers()

static void WaitForTerminatingWorkers ( ParallelState *  pstate )
static

Definition at line 448 of file parallel.c.

449{
450 while (!HasEveryWorkerTerminated(pstate))
451 {
452 ParallelSlot *slot = NULL;
453 int j;
454
455#ifndef WIN32
456 /* On non-Windows, use wait() to wait for next worker to end */
457 int status;
458 pid_t pid = wait(&status);
459
460 /* Find dead worker's slot, and clear the PID field */
461 for (j = 0; j < pstate->numWorkers; j++)
462 {
463 slot = &(pstate->parallelSlot[j]);
464 if (slot->pid == pid)
465 {
466 slot->pid = 0;
467 break;
468 }
469 }
470#else /* WIN32 */
471 /* On Windows, we must use WaitForMultipleObjects() */
472 HANDLE *lpHandles = pg_malloc(sizeof(HANDLE) * pstate->numWorkers);
473 int nrun = 0;
474 DWORD ret;
475 uintptr_t hThread;
476
477 for (j = 0; j < pstate->numWorkers; j++)
478 {
480 {
481 lpHandles[nrun] = (HANDLE) pstate->parallelSlot[j].hThread;
482 nrun++;
483 }
484 }
485 ret = WaitForMultipleObjects(nrun, lpHandles, false, INFINITE);
486 Assert(ret != WAIT_FAILED);
487 hThread = (uintptr_t) lpHandles[ret - WAIT_OBJECT_0];
488 free(lpHandles);
489
490 /* Find dead worker's slot, and clear the hThread field */
491 for (j = 0; j < pstate->numWorkers; j++)
492 {
493 slot = &(pstate->parallelSlot[j]);
494 if (slot->hThread == hThread)
495 {
496 /* For cleanliness, close handles for dead threads */
497 CloseHandle((HANDLE) slot->hThread);
498 slot->hThread = (uintptr_t) INVALID_HANDLE_VALUE;
499 break;
500 }
501 }
502#endif /* WIN32 */
503
504 /* On all platforms, update workerStatus and te[] as well */
505 Assert(j < pstate->numWorkers);
507 pstate->te[j] = NULL;
508 }
509}
static bool HasEveryWorkerTerminated(ParallelState *pstate)
Definition: parallel.c:1254

References Assert(), free, HasEveryWorkerTerminated(), j, ParallelState::numWorkers, ParallelState::parallelSlot, pg_malloc(), ParallelSlot::pid, ParallelState::te, WORKER_IS_RUNNING, ParallelSlot::workerStatus, and WRKR_TERMINATED.

Referenced by ParallelBackupEnd(), and ShutdownWorkersHard().

◆ WaitForWorkers()

void WaitForWorkers ( ArchiveHandle *  AH,
ParallelState *  pstate,
WFW_WaitOption  mode 
)

Definition at line 1453 of file parallel.c.

1454{
1455 bool do_wait = false;
1456
1457 /*
1458 * In GOT_STATUS mode, always block waiting for a message, since we can't
1459 * return till we get something. In other modes, we don't block the first
1460 * time through the loop.
1461 */
1462 if (mode == WFW_GOT_STATUS)
1463 {
1464 /* Assert that caller knows what it's doing */
1465 Assert(!IsEveryWorkerIdle(pstate));
1466 do_wait = true;
1467 }
1468
1469 for (;;)
1470 {
1471 /*
1472 * Check for status messages, even if we don't need to block. We do
1473 * not try very hard to reap all available messages, though, since
1474 * there's unlikely to be more than one.
1475 */
1476 if (ListenToWorkers(AH, pstate, do_wait))
1477 {
1478 /*
1479 * If we got a message, we are done by definition for GOT_STATUS
1480 * mode, and we can also be certain that there's at least one idle
1481 * worker. So we're done in all but ALL_IDLE mode.
1482 */
1483 if (mode != WFW_ALL_IDLE)
1484 return;
1485 }
1486
1487 /* Check whether we must wait for new status messages */
1488 switch (mode)
1489 {
1490 case WFW_NO_WAIT:
1491 return; /* never wait */
1492 case WFW_GOT_STATUS:
1493 Assert(false); /* can't get here, because we waited */
1494 break;
1495 case WFW_ONE_IDLE:
1496 if (GetIdleWorker(pstate) != NO_SLOT)
1497 return;
1498 break;
1499 case WFW_ALL_IDLE:
1500 if (IsEveryWorkerIdle(pstate))
1501 return;
1502 break;
1503 }
1504
1505 /* Loop back, and this time wait for something to happen */
1506 do_wait = true;
1507 }
1508}
static bool ListenToWorkers(ArchiveHandle *AH, ParallelState *pstate, bool do_wait)
Definition: parallel.c:1400
@ WFW_ALL_IDLE
Definition: parallel.h:35
@ WFW_GOT_STATUS
Definition: parallel.h:33
@ WFW_NO_WAIT
Definition: parallel.h:32
static PgChecksumMode mode
Definition: pg_checksums.c:55

References Assert(), do_wait, GetIdleWorker(), IsEveryWorkerIdle(), ListenToWorkers(), mode, NO_SLOT, WFW_ALL_IDLE, WFW_GOT_STATUS, WFW_NO_WAIT, and WFW_ONE_IDLE.

Referenced by DispatchJobForTocEntry(), restore_toc_entries_parallel(), and WriteDataChunks().

Variable Documentation

◆ shutdown_info

ShutdownInformation shutdown_info
static

Definition at line 154 of file parallel.c.

Referenced by on_exit_close_archive(), ParallelBackupEnd(), and ParallelBackupStart().

◆ signal_info

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