Gather-scatter communication using a crystal router. More...

Inheritance diagram for gs_crystal::gs_crystal_t:

Collaboration diagram for gs_crystal::gs_crystal_t:

[legend]

Public Member Functions
procedure, pass(this)	init (this, send_pe, recv_pe)
	Initialise crystal router based communication method See gs_comm.f90 for details.

procedure, pass(this)	free (this)
	Deallocate crystal router based communication method.

procedure, pass(this)	nbsend (this, u, n, tag, deps, strm)
	See gs_comm.f90 for more details on these routines.

procedure, pass(this)	nbrecv (this, tag)
	Post the receives of the first routing stage.

procedure, pass(this)	nbwait (this, u, n, op, strm)
	Drive the remaining routing stages and reduce what is delivered into the shared vector.

procedure, pass(this)	init_vec (this)
	Allocate the fused vector working and send buffers, sized for GS_VEC_NC components. Deferred to the first fused exchange, see gs_comm_t. The routing plan is shared with the scalar exchange and is not rebuilt here, so this stays rank local.

procedure, pass(this)	nbsend_vec (this, u, n, nc, tag, deps, strm)
	Pack the shared vector and post the send of the first routing stage, fused nc-component.

procedure, pass(this)	nbrecv_vec (this, tag, nc)
	Post the receives of the first routing stage, fused nc-component.

procedure, pass(this)	nbwait_vec (this, u, n, nc, op, strm)
	Drive the remaining routing stages and reduce what is delivered into the shared vector, fused nc-component.

procedure(gs_comm_init), deferred, pass	init gs_comm_init

procedure(gs_comm_free), deferred, pass	free gs_comm_free

procedure(gs_nbsend), deferred, pass	nbsend gs_nbsend

procedure(gs_nbrecv), deferred, pass	nbrecv gs_nbrecv

procedure(gs_nbwait), deferred, pass	nbwait gs_nbwait

procedure, pass(this)	init_dofs (this)

procedure, pass(this)	free_dofs (this)

procedure, pass(this)	init_order (this, send_pe, recv_pe)
	Obtains which ranks to send and receive data from.

procedure, pass(this)	free_order (this)

procedure, pass(this)	take_schedule (this, src)
	Take over the gather-scatter schedule (dof lists and peer order) of src, avoiding a second (expensive) pass over the connectivity. The data is moved rather than copied, so src is left without a schedule and must not be used for communication afterwards (it can still be freed). No communication resources are set up here; complete the handover with init_schedule once src has been freed, so that the two backends never hold their resources at the same time.

procedure, pass(this)	init_schedule (this)
	Set up this communication method for the schedule taken over by take_schedule. Collective, as init is.

procedure, pass(this)	init_vec (this)
	Fused vector halo exchange. Default implementations abort; backends that set vec_supported = .true. override them.

procedure, pass(this)	nbsend_vec (this, u, n, nc, tag, deps, strm)
	Default fused vector send. Abort unless a backend overrides it.

procedure, pass(this)	nbrecv_vec (this, tag, nc)
	Default fused vector receive. Abort unless a backend overrides it.

procedure, pass(this)	nbwait_vec (this, u, n, nc, op, strm)
	Default fused vector wait/reduce. Abort unless a backend overrides it.

Public Attributes
type(gs_crystal_plan_t)	plan
	The routing plan, worked out once from the schedule.

real(kind=rp), dimension(:), allocatable	buf
	Working buffer, two columns of plannwrk laid end to end. Column q starts at (q-1)*plannwrk.

real(kind=rp), dimension(:), allocatable	sbuf
	Send buffer, plannsmax words.

real(kind=rp), dimension(:), allocatable	buf_v
	Fused vector working and send buffers, the same layout scaled by GS_VEC_NC components. Positions are interleaved: position p holds its nc components at nc(p-1) + 1 .. ncp.

real(kind=rp), dimension(:), allocatable	sbuf_v

type(mpi_request), dimension(1)	sreq
	Requests of the stage in flight, at most one send and two receives.

type(mpi_request), dimension(2)	rreq

integer	nsreq = 0

integer	nrreq = 0

integer	tag = 0
	Tag of the operation in flight, taken from nbrecv since the later stages are driven from nbwait, which is not given one.

type(stack_i4_t), dimension(:), allocatable	send_dof
	A list of stacks of dof indices local to this process to send to rank_i.

type(stack_i4_t), dimension(:), allocatable	recv_dof
	recv_dof(rank_i) is a stack of dof indices local to this process to receive from rank_i. size(recv_dof) == pe_size

integer, dimension(:), allocatable	send_pe
	Array of ranks that this process should send to.

integer, dimension(:), allocatable	recv_pe
	array of ranks that this process will receive messages from

logical	vec_supported = .false.
	Whether this backend implements the fused vector (multi-component) halo exchange (nbsend_vec/nbrecv_vec/nbwait_vec). When .false., the gs_op_r3 caller falls back to nc independent scalar exchanges.

logical	vec_ready = .false.
	Whether the buffers the fused vector exchange needs are in place. They are sized GS_VEC_NC times the halo, quadrupling what the backend holds, and only gs_op_r3 ever touches them, so a backend that can allocate them on its own defers that to the first fused exchange (see init_vec) rather than paying for it in every run. A backend whose vector buffers are part of an allocation the whole run has to agree on – symmetric memory, coarrays, registered memory, an RMA window – cannot defer, since a rank with no shared dofs never reaches the first fused exchange; those allocate in init and set this there.

Detailed Description

Definition at line 65 of file gs_crystal.f90.

Member Function/Subroutine Documentation

◆ free() [1/2]

procedure, pass(this) gs_crystal::gs_crystal_t::free ( class(gs_crystal_t), intent(inout) this )

Definition at line 86 of file gs_crystal.f90.

◆ free() [2/2]

procedure(gs_comm_free), deferred, pass gs_comm::gs_comm_t::free

pure virtualinherited

Definition at line 82 of file gs_comm.f90.

◆ free_dofs()

procedure, pass(this) gs_comm::gs_comm_t::free_dofs ( class(gs_comm_t), intent(inout) this )

inherited

Definition at line 87 of file gs_comm.f90.

◆ free_order()

procedure, pass(this) gs_comm::gs_comm_t::free_order ( class(gs_comm_t), intent(inout) this )

inherited

Definition at line 89 of file gs_comm.f90.

◆ init() [1/2]

procedure, pass(this) gs_crystal::gs_crystal_t::init	(	class(gs_crystal_t), intent(inout)	this,
		type(stack_i4_t), intent(inout)	send_pe,
		type(stack_i4_t), intent(inout)	recv_pe
	)

Definition at line 85 of file gs_crystal.f90.

◆ init() [2/2]

procedure(gs_comm_init), deferred, pass gs_comm::gs_comm_t::init

pure virtualinherited

Definition at line 81 of file gs_comm.f90.

◆ init_dofs()

procedure, pass(this) gs_comm::gs_comm_t::init_dofs ( class(gs_comm_t), intent(inout) this )

inherited

Definition at line 86 of file gs_comm.f90.

◆ init_order()

procedure, pass(this) gs_comm::gs_comm_t::init_order	(	class(gs_comm_t), intent(inout)	this,
		type(stack_i4_t), intent(inout)	send_pe,
		type(stack_i4_t), intent(inout)	recv_pe
	)

inherited

Parameters

send_pe,only	contains rank ids this porcesss should send to
recv_pe,only	the ranks this process should receive from

Definition at line 88 of file gs_comm.f90.

◆ init_schedule()

procedure, pass(this) gs_comm::gs_comm_t::init_schedule ( class(gs_comm_t), intent(inout) this )

inherited

Definition at line 91 of file gs_comm.f90.

◆ init_vec() [1/2]

procedure, pass(this) gs_comm::gs_comm_t::init_vec ( class(gs_comm_t), intent(inout) this )

inherited

Note: Rank local by contract: a rank with no shared dofs skips the fused exchange entirely, so an override must not communicate.

Definition at line 94 of file gs_comm.f90.

◆ init_vec() [2/2]

procedure, pass(this) gs_crystal::gs_crystal_t::init_vec ( class(gs_crystal_t), intent(inout) this )

Definition at line 91 of file gs_crystal.f90.

◆ nbrecv() [1/2]

procedure, pass(this) gs_crystal::gs_crystal_t::nbrecv	(	class(gs_crystal_t), intent(inout)	this,
		integer, intent(in)	tag
	)

Definition at line 89 of file gs_crystal.f90.

◆ nbrecv() [2/2]

procedure(gs_nbrecv), deferred, pass gs_comm::gs_comm_t::nbrecv

pure virtualinherited

Definition at line 84 of file gs_comm.f90.

◆ nbrecv_vec() [1/2]

procedure, pass(this) gs_comm::gs_comm_t::nbrecv_vec	(	class(gs_comm_t), intent(inout)	this,
		integer, intent(in)	tag,
		integer, intent(in)	nc
	)

inherited

Definition at line 96 of file gs_comm.f90.

◆ nbrecv_vec() [2/2]

procedure, pass(this) gs_crystal::gs_crystal_t::nbrecv_vec	(	class(gs_crystal_t), intent(inout)	this,
		integer, intent(in)	tag,
		integer, intent(in)	nc
	)

Definition at line 93 of file gs_crystal.f90.

◆ nbsend() [1/2]

procedure, pass(this) gs_crystal::gs_crystal_t::nbsend	(	class(gs_crystal_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
	)

Definition at line 88 of file gs_crystal.f90.

◆ nbsend() [2/2]

procedure(gs_nbsend), deferred, pass gs_comm::gs_comm_t::nbsend

pure virtualinherited

Definition at line 83 of file gs_comm.f90.

◆ nbsend_vec() [1/2]

procedure, pass(this) gs_comm::gs_comm_t::nbsend_vec	(	class(gs_comm_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
	)

inherited

Parameters

u	compact shared buffer, component-outer: u((c-1)*n + idx)
n	number of shared dofs (per component)
nc	number of components

Definition at line 95 of file gs_comm.f90.

◆ nbsend_vec() [2/2]

procedure, pass(this) gs_crystal::gs_crystal_t::nbsend_vec	(	class(gs_crystal_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
	)

Parameters

u	compact shared buffer, component-outer: u((c-1)*n + idx)

Definition at line 92 of file gs_crystal.f90.

◆ nbwait() [1/2]

procedure, pass(this) gs_crystal::gs_crystal_t::nbwait	(	class(gs_crystal_t), intent(inout)	this,
		real(kind=rp), dimension(n), intent(inout)	u,
		integer, intent(in)	n,
		integer	op,
		type(c_ptr), intent(inout)	strm
	)

Definition at line 90 of file gs_crystal.f90.

◆ nbwait() [2/2]

procedure(gs_nbwait), deferred, pass gs_comm::gs_comm_t::nbwait

pure virtualinherited

Definition at line 85 of file gs_comm.f90.

◆ nbwait_vec() [1/2]

procedure, pass(this) gs_comm::gs_comm_t::nbwait_vec	(	class(gs_comm_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
	)

inherited

Definition at line 97 of file gs_comm.f90.

◆ nbwait_vec() [2/2]

procedure, pass(this) gs_crystal::gs_crystal_t::nbwait_vec	(	class(gs_crystal_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
	)

Definition at line 94 of file gs_crystal.f90.

◆ take_schedule()

procedure, pass(this) gs_comm::gs_comm_t::take_schedule	(	class(gs_comm_t), intent(inout)	this,
		class(gs_comm_t), intent(inout)	src
	)

inherited

Parameters

src	the backend to take the schedule from, left without one

Definition at line 90 of file gs_comm.f90.

Member Data Documentation

◆ buf

real(kind=rp), dimension(:), allocatable gs_crystal::gs_crystal_t::buf

Definition at line 70 of file gs_crystal.f90.

◆ buf_v

real(kind=rp), dimension(:), allocatable gs_crystal::gs_crystal_t::buf_v

Definition at line 76 of file gs_crystal.f90.

◆ nrreq

integer gs_crystal::gs_crystal_t::nrreq = 0

Definition at line 80 of file gs_crystal.f90.

◆ nsreq

integer gs_crystal::gs_crystal_t::nsreq = 0

Definition at line 80 of file gs_crystal.f90.

◆ plan

type(gs_crystal_plan_t) gs_crystal::gs_crystal_t::plan

Definition at line 67 of file gs_crystal.f90.

◆ recv_dof

type(stack_i4_t), dimension(:), allocatable gs_comm::gs_comm_t::recv_dof

inherited

Definition at line 58 of file gs_comm.f90.

◆ recv_pe

integer, dimension(:), allocatable gs_comm::gs_comm_t::recv_pe

inherited

Definition at line 64 of file gs_comm.f90.

◆ rreq

type(mpi_request), dimension(2) gs_crystal::gs_crystal_t::rreq

Definition at line 79 of file gs_crystal.f90.

◆ sbuf

real(kind=rp), dimension(:), allocatable gs_crystal::gs_crystal_t::sbuf

Definition at line 72 of file gs_crystal.f90.

◆ sbuf_v

real(kind=rp), dimension(:), allocatable gs_crystal::gs_crystal_t::sbuf_v

Definition at line 77 of file gs_crystal.f90.

◆ send_dof

type(stack_i4_t), dimension(:), allocatable gs_comm::gs_comm_t::send_dof

inherited

Definition at line 55 of file gs_comm.f90.

◆ send_pe

integer, dimension(:), allocatable gs_comm::gs_comm_t::send_pe

inherited

Note: : this will usually be fewer than the total number of ranks size(send_pe) <= pe_size

Definition at line 62 of file gs_comm.f90.

◆ sreq

type(mpi_request), dimension(1) gs_crystal::gs_crystal_t::sreq

Definition at line 79 of file gs_crystal.f90.

◆ tag

integer gs_crystal::gs_crystal_t::tag = 0

Definition at line 83 of file gs_crystal.f90.

◆ vec_ready

logical gs_comm::gs_comm_t::vec_ready = .false.

inherited

Definition at line 79 of file gs_comm.f90.

◆ vec_supported

logical gs_comm::gs_comm_t::vec_supported = .false.

inherited

Definition at line 68 of file gs_comm.f90.

The documentation for this type was generated from the following file:

/home/runner/work/neko/neko/src/gs/gs_crystal.f90

Public Member Functions

Public Attributes

Detailed Description

Member Function/Subroutine Documentation

◆ free() [1/2]

◆ free() [2/2]

◆ free_dofs()

◆ free_order()

◆ init() [1/2]

◆ init() [2/2]

◆ init_dofs()

◆ init_order()

◆ init_schedule()

◆ init_vec() [1/2]

◆ init_vec() [2/2]

◆ nbrecv() [1/2]

◆ nbrecv() [2/2]

◆ nbrecv_vec() [1/2]

◆ nbrecv_vec() [2/2]

◆ nbsend() [1/2]

◆ nbsend() [2/2]

◆ nbsend_vec() [1/2]

◆ nbsend_vec() [2/2]

◆ nbwait() [1/2]

◆ nbwait() [2/2]

◆ nbwait_vec() [1/2]

◆ nbwait_vec() [2/2]

◆ take_schedule()

Member Data Documentation

◆ buf

◆ buf_v

◆ nrreq

◆ nsreq

◆ plan

◆ recv_dof

◆ recv_pe

◆ rreq

◆ sbuf

◆ sbuf_v

◆ send_dof

◆ send_pe

◆ sreq

◆ tag

◆ vec_ready

◆ vec_supported