gs_caf Module Reference

Defines Coarray Fortran gather-scatter communication.

Data Types
type	gs_caf_t
	Gather-scatter communication using Coarray Fortran (F2008). Each image puts directly into the (module-level) receive coarray on the destination image. The signaling mode (NEKO_GS_CAF_SIGNALING) selects how segment ordering is established: sync uses sync images over the union of send and recv peers, atomic uses per-peer atomic_define/atomic_ref on data_ready/buf_ready counters, and event uses coarray events. More...

Functions/Subroutines
subroutine	gs_caf_init (this, send_pe, recv_pe)
	Initialise Coarray Fortran based communication method.
subroutine	gs_caf_free (this)
	Deallocate Coarray Fortran based communication method. The shared module-level recv coarray is intentionally retained so it can be reused by subsequent gs_caf_t instances.
subroutine	gs_nbsend_caf (this, u, n, deps, strm)
	Pack u into per-peer slabs and put each slab into the remote image's recv_buf. Double buffering means each round writes to a different half of the recv coarray, so no back-pressure synchronisation is needed in sync mode – the visibility synchronisation in nbwait suffices. Atomic and event modes still use their per-pair signalling.
subroutine	gs_nbrecv_caf (this)
	No-op for coarrays: senders push into the receiver's buffer, so the receive side does not need to post anything.
subroutine	gs_nbwait_caf (this, u, n, op, strm)
	Wait for all incoming puts and reduce them into u. In sync mode a sync_images bracket pairs with the senders' nbsend; in atomic mode each sender is awaited via its data_ready counter and credited via buf_ready after unpack.

Variables
integer, parameter, public	gs_caf_signal_sync = 1
integer, parameter, public	gs_caf_signal_atomic = 2
integer, parameter, public	gs_caf_signal_event = 3

Function/Subroutine Documentation

gs_caf_free()

subroutine gs_caf::gs_caf_free ( class(gs_caf_t), intent(inout)  this )

private

Definition at line 311 of file gs_caf.F90.

gs_caf_init()

subroutine gs_caf::gs_caf_init	(	class(gs_caf_t), intent(inout)	this,
		type(stack_i4_t), intent(inout)	send_pe,
		type(stack_i4_t), intent(inout)	recv_pe
	)

Definition at line 162 of file gs_caf.F90.

gs_nbrecv_caf()

subroutine gs_caf::gs_nbrecv_caf ( class(gs_caf_t), intent(inout)  this )

private

Definition at line 452 of file gs_caf.F90.

gs_nbsend_caf()

subroutine gs_caf::gs_nbsend_caf ( class(gs_caf_t), intent(inout)  this, real(kind=rp), dimension(n), intent(inout)  u, integer, intent(in)  n, type(c_ptr), intent(inout)  deps, type(c_ptr), intent(inout)  strm  )

private

Definition at line 334 of file gs_caf.F90.

gs_nbwait_caf()

subroutine gs_caf::gs_nbwait_caf ( class(gs_caf_t), intent(inout)  this, real(kind=rp), dimension(n), intent(inout)  u, integer, intent(in)  n, integer  op, type(c_ptr), intent(inout)  strm  )

private

Definition at line 460 of file gs_caf.F90.

Variable Documentation

gs_caf_signal_atomic

integer, parameter, public gs_caf::gs_caf_signal_atomic = 2

Definition at line 54 of file gs_caf.F90.

gs_caf_signal_event

integer, parameter, public gs_caf::gs_caf_signal_event = 3

Definition at line 55 of file gs_caf.F90.

gs_caf_signal_sync

integer, parameter, public gs_caf::gs_caf_signal_sync = 1

Definition at line 53 of file gs_caf.F90.