src/include/storage/barrier.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * barrier.h
   4  *        Barriers for synchronizing cooperating processes.
   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/storage/barrier.h
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13 #ifndef BARRIER_H
  14 #define BARRIER_H
  15
  16 /*
  17  * For the header previously known as "barrier.h", please include
  18  * "port/atomics.h", which deals with atomics, compiler barriers and memory
  19  * barriers.
  20  */
  21
  22 #include "storage/condition_variable.h"
  23 #include "storage/spin.h"
  24
  25 typedef struct Barrier
  26 {
  27         slock_t         mutex;
  28         int                     phase;                  /* phase counter */
  29         int                     participants;   /* the number of participants attached */
  30         int                     arrived;                /* the number of participants that have
  31                                                                  * arrived */
  32         int                     elected;                /* highest phase elected */
  33         bool            static_party;   /* used only for assertions */
  34         ConditionVariable condition_variable;
  35 } Barrier;
  36
  37 extern void BarrierInit(Barrier *barrier, int num_workers);
  38 extern bool BarrierArriveAndWait(Barrier *barrier, uint32 wait_event_info);
  39 extern bool BarrierArriveAndDetach(Barrier *barrier);
  40 extern bool BarrierArriveAndDetachExceptLast(Barrier *barrier);
  41 extern int      BarrierAttach(Barrier *barrier);
  42 extern bool BarrierDetach(Barrier *barrier);
  43 extern int      BarrierPhase(Barrier *barrier);
  44 extern int      BarrierParticipants(Barrier *barrier);
  45
  46 #endif                                                  /* BARRIER_H */