diff options
Diffstat (limited to 'src/include/storage/latch.h')
| -rw-r--r-- | src/include/storage/latch.h | 37 |
1 files changed, 32 insertions, 5 deletions
diff --git a/src/include/storage/latch.h b/src/include/storage/latch.h index 1b9521f5a69..85d211c0e1c 100644 --- a/src/include/storage/latch.h +++ b/src/include/storage/latch.h @@ -68,6 +68,12 @@ * use of any generic handler. * * + * WaitEventSets allow to wait for latches being set and additional events - + * postmaster dying and socket readiness of several sockets currently - at the + * same time. On many platforms using a long lived event set is more + * efficient than using WaitLatch or WaitLatchOrSocket. + * + * * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * @@ -95,13 +101,27 @@ typedef struct Latch #endif } Latch; -/* Bitmasks for events that may wake-up WaitLatch() clients */ +/* + * Bitmasks for events that may wake-up WaitLatch(), WaitLatchOrSocket(), or + * WaitEventSetWait(). + */ #define WL_LATCH_SET (1 << 0) #define WL_SOCKET_READABLE (1 << 1) #define WL_SOCKET_WRITEABLE (1 << 2) -#define WL_TIMEOUT (1 << 3) +#define WL_TIMEOUT (1 << 3) /* not for WaitEventSetWait() */ #define WL_POSTMASTER_DEATH (1 << 4) +typedef struct WaitEvent +{ + int pos; /* position in the event data structure */ + uint32 events; /* triggered events */ + pgsocket fd; /* socket fd associated with event */ + void *user_data; /* pointer provided in AddWaitEventToSet */ +} WaitEvent; + +/* forward declaration to avoid exposing latch.c implementation details */ +typedef struct WaitEventSet WaitEventSet; + /* * prototypes for functions in latch.c */ @@ -110,12 +130,19 @@ extern void InitLatch(volatile Latch *latch); extern void InitSharedLatch(volatile Latch *latch); extern void OwnLatch(volatile Latch *latch); extern void DisownLatch(volatile Latch *latch); -extern int WaitLatch(volatile Latch *latch, int wakeEvents, long timeout); -extern int WaitLatchOrSocket(volatile Latch *latch, int wakeEvents, - pgsocket sock, long timeout); extern void SetLatch(volatile Latch *latch); extern void ResetLatch(volatile Latch *latch); +extern WaitEventSet *CreateWaitEventSet(MemoryContext context, int nevents); +extern void FreeWaitEventSet(WaitEventSet *set); +extern int AddWaitEventToSet(WaitEventSet *set, uint32 events, pgsocket fd, + Latch *latch, void *user_data); +extern void ModifyWaitEvent(WaitEventSet *set, int pos, uint32 events, Latch *latch); + +extern int WaitEventSetWait(WaitEventSet *set, long timeout, WaitEvent *occurred_events, int nevents); +extern int WaitLatch(volatile Latch *latch, int wakeEvents, long timeout); +extern int WaitLatchOrSocket(volatile Latch *latch, int wakeEvents, + pgsocket sock, long timeout); /* * Unix implementation uses SIGUSR1 for inter-process signaling. |