src/include/access/parallel.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * parallel.h
   4  *        Infrastructure for launching parallel workers
   5  *
   6  * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  * src/include/access/parallel.h
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13
  14 #ifndef PARALLEL_H
  15 #define PARALLEL_H
  16
  17 #include "access/xlogdefs.h"
  18 #include "lib/ilist.h"
  19 #include "postmaster/bgworker.h"
  20 #include "storage/shm_mq.h"
  21 #include "storage/shm_toc.h"
  22
  23 typedef void (*parallel_worker_main_type) (dsm_segment *seg, shm_toc *toc);
  24
  25 typedef struct ParallelWorkerInfo
  26 {
  27         BackgroundWorkerHandle *bgwhandle;
  28         shm_mq_handle *error_mqh;
  29         int32           pid;
  30 } ParallelWorkerInfo;
  31
  32 typedef struct ParallelContext
  33 {
  34         dlist_node      node;
  35         SubTransactionId subid;
  36         int                     nworkers;               /* Maximum number of workers to launch */
  37         int                     nworkers_to_launch; /* Actual number of workers to launch */
  38         int                     nworkers_launched;
  39         char       *library_name;
  40         char       *function_name;
  41         ErrorContextCallback *error_context_stack;
  42         shm_toc_estimator estimator;
  43         dsm_segment *seg;
  44         void       *private_memory;
  45         shm_toc    *toc;
  46         ParallelWorkerInfo *worker;
  47         int                     nknown_attached_workers;
  48         bool       *known_attached_workers;
  49 } ParallelContext;
  50
  51 typedef struct ParallelWorkerContext
  52 {
  53         dsm_segment *seg;
  54         shm_toc    *toc;
  55 } ParallelWorkerContext;
  56
  57 extern volatile bool ParallelMessagePending;
  58 extern PGDLLIMPORT int ParallelWorkerNumber;
  59 extern PGDLLIMPORT bool InitializingParallelWorker;
  60
  61 #define         IsParallelWorker()              (ParallelWorkerNumber >= 0)
  62
  63 extern ParallelContext *CreateParallelContext(const char *library_name,
  64                                                                                           const char *function_name, int nworkers);
  65 extern void InitializeParallelDSM(ParallelContext *pcxt);
  66 extern void ReinitializeParallelDSM(ParallelContext *pcxt);
  67 extern void ReinitializeParallelWorkers(ParallelContext *pcxt, int nworkers_to_launch);
  68 extern void LaunchParallelWorkers(ParallelContext *pcxt);
  69 extern void WaitForParallelWorkersToAttach(ParallelContext *pcxt);
  70 extern void WaitForParallelWorkersToFinish(ParallelContext *pcxt);
  71 extern void DestroyParallelContext(ParallelContext *pcxt);
  72 extern bool ParallelContextActive(void);
  73
  74 extern void HandleParallelMessageInterrupt(void);
  75 extern void HandleParallelMessages(void);
  76 extern void AtEOXact_Parallel(bool isCommit);
  77 extern void AtEOSubXact_Parallel(bool isCommit, SubTransactionId mySubId);
  78 extern void ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end);
  79
  80 extern void ParallelWorkerMain(Datum main_arg);
  81
  82 #endif                                                  /* PARALLEL_H */