2 This source code file is part of thread_mpi.
3 Written by Sander Pronk, Erik Lindahl, and possibly others.
5 Copyright (c) 2009, Sander Pronk, Erik Lindahl.
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34 be called official thread_mpi. Details are found in the README & COPYING
41 #include "visibility.h"
46 \brief Event notification wait and signaling functions.
48 The event structure offers lightweight signaling and scheduler-yielding
49 (but still spinning) waiting for waits of intermediate durations (i.e.
50 longer than appropriate for a spin lock but shorter than mutex_cond_wait().
51 These functions only take care of the waiting and signaling; the user is
52 responsible for the handling of the actual event structures and condition
56 /*! \brief Event notification structure.
58 Structure for notifying one thread that something has happened, allowing
59 that thread to wait, and possibly give up its timeslice. This structure
60 only takes care of the notification itself, and will not handle data
61 about incoming events - that is left up to the user.
63 This structure allows notification of a single thread by any number of
65 typedef struct tMPI_Event_t tMPI_Event;
68 tMPI_Atomic_t sync; /* the event sync counter */
69 int last_sync; /* the last sync event looked at */
70 TMPI_YIELD_WAIT_DATA /* data associated with yielding */
75 /*! \brief Initialize the event object.
77 \param ev The event structure to be intialized. */
79 void tMPI_Event_init(tMPI_Event *ev);
81 /*! \brief Deallocate the internals of the contents of event object.
83 \param ev The event structure to be destroyed. */
85 void tMPI_Event_destroy(tMPI_Event *ev);
87 /*! \brief Wait for an event to occur.
89 Sets the number of events that had occurred during the wait in N.
90 \param ev The event structure to wait on.
91 \returns The number of events that have occurred at function
94 int tMPI_Event_wait(tMPI_Event *ev);
97 /*! \brief Signal an event, possibly waking an tMPI_Event_wait().
99 \param ev The event to signal. */
101 void tMPI_Event_signal(tMPI_Event *ev);
103 #define tMPI_Event_signal(ev) \
105 tMPI_Atomic_memory_barrier_rel(); \
106 tMPI_Atomic_add_return( &((ev)->sync), 1); \
111 /*! \brief Signal processing of an event.
113 Each event that is handled by the receiver, must be processed through
114 tMPI_Event_process(). Unprocessed events will make tMPI_Event_wait() return
117 \param ev The event object.
118 \param N The number of processed events. */
120 void tMPI_Event_process(tMPI_Event *ev, int N);
122 #define tMPI_Event_process(ev, N) \
124 (ev)->last_sync += N; \
128 #endif /* TMPI_EVENT_H_ */