Virtual (currently just MPI) communications layer. More...

Files
file	vcom.h
	Class Vcom: virtual (currently just MPI) communications layer.

Classes
struct	sVcom
	Contains public data members for Vcom class. More...

Typedefs
typedef struct sVcom	Vcom
	Declaration of the Vcom class as the Vcom structure.

Functions
int	Vcom_init (int argc, char **argv)
	The Vmp initializer.
int	Vcom_finalize (void)
	The Vmp finalizer.
Vcom *	Vcom_ctor (int commtype)
	Construct the communications object. This routine sets up data members of class and initializes MPI.
int	Vcom_ctor2 (Vcom *thee, int commtype)
	Construct the communications object. This routine sets up data members of class and initializes MPI. This is broken into two parts to be callable from FORTRAN.
void	Vcom_dtor (Vcom **thee)
	Destroy the communications object.
void	Vcom_dtor2 (Vcom *thee)
	Destroy the communications object. This is broken into two parts to be callable from FORTRAN.
int	Vcom_send (Vcom thee, int des, void buf, int len, int type, int block)
	Send a buffer. Returns 1 on success.
int	Vcom_recv (Vcom thee, int src, void buf, int len, int type, int block)
	Receive a (character) buffer. The blocking flag is present, but not used. All receives are assumed to be blocking. A non-blocking receive would be very ugly to implement (signals or something?).
int	Vcom_reduce (Vcom thee, void sendbuf, void *recvbuf, int length, int type, int op)
	Perform a blocking probe to get the length (in number of items of specified type) of an incoming message and place it in the argument ``length".
int	Vcom_size (Vcom *thee)
	Get the number of PEs in communicator.
int	Vcom_resize (Vcom *thee, int newsize)
	Resize (shrink) the communications group to include only newsize number of processors. Obsolete processes are given rank of -1 and size of 0.
int	Vcom_rank (Vcom *thee)
	Get the ID of the local PE.
int	Vcom_barr (Vcom *thee)
	Synchronization barrier.

Detailed Description

Virtual (currently just MPI) communications layer.

Typedef Documentation

◆ Vcom

typedef struct sVcom Vcom

Declaration of the Vcom class as the Vcom structure.

Author: Michael Holst

Returns: None

Function Documentation

◆ Vcom_barr()

int Vcom_barr ( Vcom * thee )

Synchronization barrier.

Author: Michael Holst

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: 1 if successful.

Parameters

thee	Pointer to the communications object

◆ Vcom_ctor()

Vcom * Vcom_ctor ( int commtype )

Construct the communications object. This routine sets up data members of class and initializes MPI.

Author: Michael Holst

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: Pointer to the new allocated communications object.

Parameters

commtype type of communications object

◆ Vcom_ctor2()

int Vcom_ctor2	(	Vcom *	thee,
		int	commtype )

Construct the communications object. This routine sets up data members of class and initializes MPI. This is broken into two parts to be callable from FORTRAN.

Authors: Nathan Baker and Michael Holst

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: Success enumeration

Parameters

thee	Pointer to the new allocated communications object.
commtype	type of communications object

◆ Vcom_dtor()

void Vcom_dtor ( Vcom ** thee )

Destroy the communications object.

Authors: Nathan Baker and Michael Holst

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: None

Parameters

thee	Pointer to the communications object.

◆ Vcom_dtor2()

void Vcom_dtor2 ( Vcom * thee )

Destroy the communications object. This is broken into two parts to be callable from FORTRAN.

Authors: Nathan Baker and Michael Holst

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: None

Parameters

thee	Pointer to the communications object.

◆ Vcom_finalize()

int Vcom_finalize ( void )

The Vmp finalizer.

Author: Michael Holst

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: Success enumeration

◆ Vcom_init()

int Vcom_init	(	int *	argc,
		char ***	argv )

The Vmp initializer.

Author: Michael Holst

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: Success enumeration

Parameters

argc	number of the command line arguments
argv	the command line arguments

◆ Vcom_rank()

int Vcom_rank ( Vcom * thee )

Get the ID of the local PE.

Authors: Nathan Baker and Michael Holst

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: Get the ID of the local PE

Parameters

thee	Pointer to the communications object

◆ Vcom_recv()

int Vcom_recv	(	Vcom *	thee,
		int	src,
		void *	buf,
		int	len,
		int	type,
		int	block )

Receive a (character) buffer.
The blocking flag is present, but not used. All receives are assumed to be blocking. A non-blocking receive would be very ugly to implement (signals or something?).

Authors: Nathan Baker and Michael Holst

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: 1 if successful

Parameters

thee	Pointer to the communications object.
src	rank of receiving processor
buf	pointer to buffer of previously allocated memory
len	number of items (of declared type) in buffer
type	type of items in message. 0 => MPI_BYTE, 1 => MPI_INT, 2 => MPI_DOUBLE, 3 => MPI_CHAR
block	toggles blocking on (=1) and off (=0)

◆ Vcom_reduce()

int Vcom_reduce	(	Vcom *	thee,
		void *	sendbuf,
		void *	recvbuf,
		int	length,
		int	type,
		int	op )

Perform a blocking probe to get the length (in number of items of specified type) of an incoming message and place it in the
argument ``length".

Author: Nathan Baker

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: Success enumeration

Parameters

thee	Pointer to the communications object.
src	rank of receiving processor
length	Pointer to perform a blocking probe
type	type of items in message. 0 => MPI_BYTE, 1 => MPI_INT, 2 => MPI_DOUBLE, 3 => MPI_CHAR / int Vcom_getCount(Vcom thee, int src, int *length, int type);

/**

Perform a reduction of the data across all processors. This is equivalent (and in the case of MPI is identical to) MPI_Allreduce. Basically, the specified operations are appleed to each member of
the sendbuf across all processors and the results are written to recvbuf.

Author: Nathan Baker

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: Success enumeration

Parameters

thee	Pointer to the communications object
sendbuf	buffer containing length items of the specified type to be operated on
recvbuf	buffer containing length items of the specified type after operation
length	number of items
type	type of items in message 0 => MPI_BYTE, 1 => MPI_INT, 2 => MPI_DOUBLE, 3 => MPI_CHAR
op	operation to perform 0 => MPI_SUM, 1 => MPI_PROD, 2 => MPI_MIN, 3 => MPI_MAX

◆ Vcom_resize()

int Vcom_resize	(	Vcom *	thee,
		int	newsize )

Resize (shrink) the communications group to include only newsize number of processors.
Obsolete processes are given rank of -1 and size of 0.

Author: Nathan Baker

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: 1 if successful

Parameters

thee	Pointer to the communications object
newsize	number of processors

◆ Vcom_send()

int Vcom_send	(	Vcom *	thee,
		int	des,
		void *	buf,
		int	len,
		int	type,
		int	block )

Send a buffer. Returns 1 on success.

Authors: Nathan Baker and Michael Holst

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: 1 if successful

Parameters

thee	Pointer to the communications object.
des	rank of receiving processor
buf	buffer containing message
len	number of items (of declared type) in buffer
type	type of items in message. 0 => MPI_BYTE, 1 => MPI_INT, 2 => MPI_DOUBLE, 3 => MPI_CHAR
block	toggles blocking on (=1) and off (=0)

◆ Vcom_size()

int Vcom_size ( Vcom * thee )

Get the number of PEs in communicator.

Authors: Nathan Baker Michael Holst

Note: Class Vcom: Non-Inlineable methods (vcom.c)

Returns: Number of PEs or -1 if error

Parameters

thee	Pointer to the communications object

Files

Classes

Typedefs

Functions

Detailed Description

Typedef Documentation

◆ Vcom

Function Documentation

◆ Vcom_barr()

◆ Vcom_ctor()

◆ Vcom_ctor2()

◆ Vcom_dtor()

◆ Vcom_dtor2()

◆ Vcom_finalize()

◆ Vcom_init()

◆ Vcom_rank()

◆ Vcom_recv()

◆ Vcom_reduce()

◆ Vcom_resize()

◆ Vcom_send()

◆ Vcom_size()