device_management.cpp File Reference

#include "gmxpre.h"
#include "device_management.h"
#include "gromacs/utility/fatalerror.h"
#include "device_information.h"

Include dependency graph for device_management.cpp:

Description

Defines the CPU stubs for the device management.

Author

Anca Hamuraru anca@.nosp@m.stre.nosp@m.amcom.nosp@m.puti.nosp@m.ng.eu

Dimitrios Karkoulis dimit.nosp@m.ris..nosp@m.karko.nosp@m.ulis.nosp@m.@gmai.nosp@m.l.co.nosp@m.m

Teemu Virolainen teemu.nosp@m.@str.nosp@m.eamco.nosp@m.mput.nosp@m.ing.e.nosp@m.u

Mark Abraham mark..nosp@m.j.ab.nosp@m.raham.nosp@m.@gma.nosp@m.il.co.nosp@m.m

Szilárd Páll pall..nosp@m.szil.nosp@m.ard@g.nosp@m.mail.nosp@m..com

Artem Zhmurov zhmur.nosp@m.ov@g.nosp@m.mail..nosp@m.com

Functions
std::vector< std::unique_ptr < DeviceInformation > >	findDevices ()
	Find all GPUs in the system. More...
void	setActiveDevice (const DeviceInformation &)
	Set the active GPU. More...
void	releaseDevice ()
	Releases the GPU device used by the active context at the time of calling. More...
std::string	getDeviceInformationString (const DeviceInformation &)
	Formats and returns a device information string for a given GPU. More...
bool	isDeviceDetectionFunctional (std::string *)
	Return whether GPU detection is functioning correctly. More...
void	doubleCheckGpuAwareMpiWillWork (const DeviceInformation &)

Function Documentation

void doubleCheckGpuAwareMpiWillWork

(

const DeviceInformation &

deviceInfo

)

Run a possible check that GPU-aware MPI will work on deviceInfo

Exceptions

InvalidInputError

if the user's choices would lead to a crash

std::vector<std::unique_ptr<DeviceInformation> > findDevices

(

)

Find all GPUs in the system.

Will detect every GPU supported by the device driver in use. Must only be called if canPerformDeviceDetection() has returned true. This routine also checks for the compatibility of each device and fill the deviceInfo array with the required information on each device: ID, device properties, status.

Note that this function leaves the GPU runtime API error state clean; this is implemented ATM in the CUDA flavor. This invalidates any existing CUDA streams, allocated memory on GPU, etc.

Todo:

: Check if errors do propagate in OpenCL as they do in CUDA and whether there is a mechanism to "clear" them.

Returns

Standard vector with the list of devices found

Exceptions

InternalError

if a GPU API returns an unexpected failure (because the call to canDetectGpus() should always prevent this occuring)

std::string getDeviceInformationString

(

const DeviceInformation &

deviceInfo

)

Formats and returns a device information string for a given GPU.

Given an index directly into the array of available GPUs, returns a formatted info string for the respective GPU which includes ID, name, compute capability, and detection status.

Parameters

[in]

deviceInfo

An information on device that is to be set.

Returns

A string describing the device.

bool isDeviceDetectionFunctional

(

std::string *

errorMessage

)

Return whether GPU detection is functioning correctly.

Returns true when this is a build of GROMACS configured to support GPU usage, and a valid device driver, ICD, and/or runtime was detected.

This function is not intended to be called from build configurations that do not support GPUs, and there will be no descriptive message in that case.

Parameters

[out]

errorMessage

When returning false on a build configured with GPU support and non-nullptr was passed, the string contains a descriptive message about why GPUs cannot be detected.

Does not throw.

void releaseDevice

(

)

Releases the GPU device used by the active context at the time of calling.

With CUDA, the device is reset and therefore all data uploaded to the GPU is lost. This must only be called when none of this data is required anymore, because subsequent attempts to free memory associated with the context will otherwise fail. Calls gmx_warning upon errors.

With other GPU SDKs, does nothing.

Should only be called after setActiveDevice was called.

void setActiveDevice

(

const DeviceInformation &

deviceInfo

)

Set the active GPU.

This sets the device for which the device information is passed active. Essential in CUDA, where the device buffers and kernel launches are not connected to the device context. In OpenCL, checks the device vendor and makes vendor-specific performance adjustments.

Parameters

[in]

deviceInfo

Information on the device to be set.

Issues a fatal error for any critical errors that occur during initialization.