gs_device_shmem Module Reference

Defines GPU aware MPI gather-scatter communication.

Data Types
interface	cuda_gs_nvshmem_pack
interface	cuda_gs_nvshmem_pack_vec
interface	cuda_gs_post_ready
interface	cuda_gs_push
interface	cuda_gs_push_wait
interface	cuda_gs_unpack
interface	cuda_gs_unpack_vec
interface	cudafree_nvshmem
interface	cudamalloc_nvshmem
type	gs_device_shmem_buf_t
	Buffers for non-blocking communication and packing/unpacking. More...
type	gs_device_shmem_t
	Gather-scatter communication using device SHMEM. The arrays are indexed per PE like send_pe and @ recv_pe. More...

Functions/Subroutines
subroutine	gs_device_shmem_buf_init (this, pe_order, dof_stack, mark_dupes, nslabs)
subroutine	gs_device_shmem_buf_free (this)
subroutine	gs_device_shmem_init (this, send_pe, recv_pe)
	Initialise MPI based communication method.
subroutine	gs_device_shmem_free (this)
	Deallocate MPI based communication method.
subroutine	gs_device_shmem_nbsend (this, u, n, tag, deps, strm)
	Post non-blocking send operations.
subroutine	gs_device_shmem_nbrecv (this, tag)
	Post non-blocking receive operations.
subroutine	gs_device_shmem_nbwait (this, u, n, op, strm)
	Wait for non-blocking operations.
subroutine	gs_device_shmem_nbsend_vec (this, u, n, nc, tag, deps, strm)
	Fused nc-component send. u is the compact shared device buffer (component-outer, per-component stride n = nshared). Bulk-packs the parity slab of the fused vector send buffer; see gs_device_shmem_nbsend for the ordering and parity-slab rationale.
subroutine	gs_device_shmem_nbrecv_vec (this, tag, nc)
	No-op: everything happens in nbwait_vec.
subroutine	gs_device_shmem_nbwait_vec (this, u, n, nc, op, strm)
	Fused nc-component push + unpack (the pack happens in nbsend_vec).

Variables
logical, parameter, public	gs_device_shmem_avail = .false.
	Whether NVSHMEM was built into this Neko (–with-nvshmem). Lets callers (e.g. the gs comm. autotuner) skip the backend rather than exchanging nothing on builds without it.

Function/Subroutine Documentation

gs_device_shmem_buf_free()

subroutine gs_device_shmem::gs_device_shmem_buf_free ( class(gs_device_shmem_buf_t), intent(inout)  this )

private

Definition at line 296 of file gs_device_shmem.F90.

Here is the call graph for this function:

gs_device_shmem_buf_init()

subroutine gs_device_shmem::gs_device_shmem_buf_init ( class(gs_device_shmem_buf_t), intent(inout)  this, integer, dimension(:), intent(inout), allocatable  pe_order, type(stack_i4_t), dimension(:), intent(inout), allocatable  dof_stack, logical, intent(in)  mark_dupes, integer, intent(in)  nslabs  )

private

Parameters

nslabs

number of parity slabs (2 for send buffers, which are round-parity double-buffered so a slab is never repacked while a previous non-blocking put may still be draining it; 1 for recv buffers, whose overwrite is gated by the ready signal).

Definition at line 213 of file gs_device_shmem.F90.

Here is the call graph for this function:

gs_device_shmem_free()

subroutine gs_device_shmem::gs_device_shmem_free ( class(gs_device_shmem_t), intent(inout)  this )

private

Definition at line 398 of file gs_device_shmem.F90.

Here is the call graph for this function:

gs_device_shmem_init()

subroutine gs_device_shmem::gs_device_shmem_init ( class(gs_device_shmem_t), intent(inout)  this, type(stack_i4_t), intent(inout)  send_pe, type(stack_i4_t), intent(inout)  recv_pe  )

private

Definition at line 313 of file gs_device_shmem.F90.

Here is the call graph for this function:

gs_device_shmem_nbrecv()

subroutine gs_device_shmem::gs_device_shmem_nbrecv ( class(gs_device_shmem_t), intent(inout)  this, integer, intent(in)  tag  )

private

Definition at line 498 of file gs_device_shmem.F90.

gs_device_shmem_nbrecv_vec()

subroutine gs_device_shmem::gs_device_shmem_nbrecv_vec ( class(gs_device_shmem_t), intent(inout)  this, integer, intent(in)  tag, integer, intent(in)  nc  )

private

Definition at line 597 of file gs_device_shmem.F90.

gs_device_shmem_nbsend()

subroutine gs_device_shmem::gs_device_shmem_nbsend ( class(gs_device_shmem_t), intent(inout)  this, real(kind=rp), dimension(n), intent(inout)  u, integer, intent(in)  n, integer, intent(in)  tag, type(c_ptr), intent(inout)  deps, type(c_ptr), intent(inout)  strm  )

private

Definition at line 444 of file gs_device_shmem.F90.

Here is the call graph for this function:

gs_device_shmem_nbsend_vec()

subroutine gs_device_shmem::gs_device_shmem_nbsend_vec ( class(gs_device_shmem_t), intent(inout)  this, real(kind=rp), dimension(nc*n), intent(inout)  u, integer, intent(in)  n, integer, intent(in)  nc, integer, intent(in)  tag, type(c_ptr), intent(inout)  deps, type(c_ptr), intent(inout)  strm  )

private

Definition at line 562 of file gs_device_shmem.F90.

Here is the call graph for this function:

gs_device_shmem_nbwait()

subroutine gs_device_shmem::gs_device_shmem_nbwait ( class(gs_device_shmem_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 508 of file gs_device_shmem.F90.

Here is the call graph for this function:

gs_device_shmem_nbwait_vec()

subroutine gs_device_shmem::gs_device_shmem_nbwait_vec ( class(gs_device_shmem_t), intent(inout)  this, real(kind=rp), dimension(nc*n), intent(inout)  u, integer, intent(in)  n, integer, intent(in)  nc, integer  op, type(c_ptr), intent(inout)  strm  )

private

Definition at line 603 of file gs_device_shmem.F90.

Here is the call graph for this function:

Variable Documentation

gs_device_shmem_avail

logical, parameter, public gs_device_shmem::gs_device_shmem_avail = .false.

Definition at line 57 of file gs_device_shmem.F90.