| <?xml version="1.0" encoding="UTF-8"?> |
| <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN" |
| "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd" [ |
| <!ENTITY clCreate_memflagsInc SYSTEM "clCreate_memflagsInc.xml"> |
| ]> |
| |
| <refentry> |
| <refentryinfo> |
| <keywordset> |
| <keyword>clCreateSubDevices</keyword> |
| </keywordset> |
| </refentryinfo> |
| |
| <refmeta> |
| <refentrytitle> |
| clCreateSubDevices |
| </refentrytitle> |
| |
| <refmiscinfo> |
| <copyright> |
| <year>2007-2013</year> |
| <holder>The Khronos Group Inc. |
| Permission is hereby granted, free of charge, to any person obtaining a |
| copy of this software and/or associated documentation files (the |
| "Materials"), to deal in the Materials without restriction, including |
| without limitation the rights to use, copy, modify, merge, publish, |
| distribute, sublicense, and/or sell copies of the Materials, and to |
| permit persons to whom the Materials are furnished to do so, subject to |
| the condition that this copyright notice and permission notice shall be included |
| in all copies or substantial portions of the Materials.</holder> |
| </copyright> |
| </refmiscinfo> |
| <manvolnum>3</manvolnum> |
| </refmeta> |
| |
| <!-- ================================ SYNOPSIS --> |
| |
| <refnamediv id="clCreateSubDevices"> |
| <refname> |
| clCreateSubDevices |
| </refname> |
| |
| <refpurpose> |
| Creates an array of sub-devices that each reference a non-intersecting set of compute units within <varname>in_device</varname>. |
| </refpurpose> |
| </refnamediv> |
| |
| <refsynopsisdiv xmlns:xlink="http://www.w3.org/1999/xlink"><title></title> |
| <funcsynopsis> |
| <funcprototype> |
| <funcdef> |
| <link xlink:href="scalarDataTypes.html">cl_int</link> <function>clCreateSubDevices</function> |
| </funcdef> |
| <paramdef> |
| <link xlink:href="abstractDataTypes.html">cl_device_id</link> |
| <parameter>in_device</parameter> |
| </paramdef> |
| <paramdef>const |
| <link xlink:href="enums.html#cl_device_partition_property">cl_device_partition_property</link> |
| <parameter>*properties</parameter> |
| </paramdef> |
| <paramdef> |
| <link xlink:href="scalarDataTypes.html">cl_uint</link> |
| <parameter>num_devices</parameter> |
| </paramdef> |
| <paramdef> |
| <link xlink:href="scalarDataTypes.html">cl_device_id</link> |
| <parameter>*out_devices</parameter> |
| </paramdef> |
| <paramdef><link xlink:href="scalarDataTypes.html">cl_uint</link> |
| <parameter>*num_devices_ret</parameter> |
| </paramdef> |
| |
| </funcprototype> |
| </funcsynopsis> |
| </refsynopsisdiv> |
| |
| <!-- ================================ PARAMETERS --> |
| |
| <refsect1 id="parameters"> |
| <title>Parameters</title> |
| <variablelist> |
| <varlistentry> |
| <term><varname>in_device</varname></term> |
| <listitem> |
| <para>The device to be partitioned.</para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>properties</varname></term> |
| <listitem> |
| <para> |
| Specifies how <varname>in_device</varname> is to be partition described |
| by a partition name and its corresponding value. Each partition name |
| is immediately followed by the corresponding desired value. The list is |
| terminated with 0. The list of supported partitioning schemes is described |
| in the table below. Only one of the listed partitioning schemes can be |
| specified in <varname>properties</varname>. |
| </para> |
| |
| <!-- table 5.4 --> |
| <informaltable frame="all"> |
| <tgroup cols="2" align="left" colsep="1" rowsep="1"> |
| <colspec colname="col1" colnum="1" /> |
| <colspec colname="col2" colnum="2" /> |
| <thead> |
| <row> |
| <entry>cl_device_partition_property enum (Partition value)</entry> |
| <entry>Description</entry> |
| </row> |
| </thead> |
| |
| <tbody> |
| <row> |
| <entry>CL_DEVICE_PARTITION_EQUALLY (unsigned int)</entry> |
| <entry> |
| Split the aggregate device into as many smaller |
| aggregate devices as can be created, each |
| containing <replaceable>n</replaceable> compute |
| units. The value <replaceable>n</replaceable> is |
| passed as the value accompanying this property. If |
| <replaceable>n</replaceable> does not divide evenly into |
| <constant>CL_DEVICE_PARTITION_MAX_COMPUTE_UNITS</constant>, |
| then the remaining compute units are not used. |
| </entry> |
| </row> |
| |
| <row> |
| <entry>CL_DEVICE_PARTITION_BY_COUNTS (unsigned int)</entry> |
| <entry> |
| This property is followed by a |
| <constant>CL_DEVICE_PARTITION_BY_COUNTS_LIST_END</constant> |
| terminated list of compute unit counts. For |
| each nonzero count <replaceable>m</replaceable> |
| in the list, a sub-device is created with |
| <replaceable>m</replaceable> compute units in it. |
| <constant>CL_DEVICE_PARTITION_BY_COUNTS_LIST_END</constant> |
| is defined to be 0. |
| |
| <para> |
| The number of non-zero count |
| entries in the list may not exceed |
| <constant>CL_DEVICE_PARTITION_MAX_SUB_DEVICES</constant>. |
| </para> |
| |
| <para> |
| The total number of compute |
| units specified may not exceed |
| <constant>CL_DEVICE_PARTITION_MAX_COMPUTE_UNITS</constant>. |
| </para> |
| </entry> |
| </row> |
| |
| <row> |
| <entry>CL_DEVICE_PARTITION_BY_- |
| AFFINITY_DOMAIN (cl_device_affinity_domain)</entry> |
| <entry> |
| Split the device into smaller aggregate devices |
| containing one or more compute units that all share |
| part of a cache hierarchy. The value accompanying |
| this property may be drawn from the following list: |
| |
| <para> |
| <constant>CL_DEVICE_AFFINITY_DOMAIN_NUMA</constant> |
| - Split the device into sub-devices comprised of |
| compute units that share a NUMA node. |
| </para> |
| |
| <para> |
| <constant>CL_DEVICE_AFFINITY_DOMAIN_L4_CACHE</constant> |
| - Split the device into sub-devices comprised of |
| compute units that share a level 4 data cache. |
| </para> |
| |
| <para> |
| <constant>CL_DEVICE_AFFINITY_DOMAIN_L3_CACHE</constant> |
| - Split the device into sub-devices comprised of |
| compute units that share a level 3 data cache. |
| </para> |
| |
| <para> |
| <constant>CL_DEVICE_AFFINITY_DOMAIN_L2_CACHE</constant> |
| - Split the device into sub-devices comprised of |
| compute units that share a level 2 data cache. |
| </para> |
| |
| <para> |
| <constant>CL_DEVICE_AFFINITY_DOMAIN_L1_CACHE</constant> |
| - Split the device into sub-devices comprised of |
| compute units that share a level 1 data cache. |
| </para> |
| |
| <para> |
| <constant>CL_DEVICE_AFFINITY_DOMAIN_NEXT_PARTITIONABLE</constant> |
| - Split the device along the next partitionable |
| affinity domain. The implementation shall find the |
| first level along which the device or sub-device |
| may be further subdivided in the order NUMA, |
| L4, L3, L2, L1, and partition the device into |
| sub-devices comprised of compute units that share |
| memory subsystems at this level. |
| </para> |
| |
| <para> |
| The user may determine what happened by calling |
| <citerefentry><refentrytitle>clGetDeviceInfo</refentrytitle></citerefentry> |
| (<constant>CL_DEVICE_PARTITION_TYPE</constant>) |
| on the sub-devices. |
| </para> |
| </entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </informaltable> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>num_devices</varname></term> |
| <listitem> |
| <para> |
| Size of memory pointed to by <varname>out_devices</varname> specified as |
| the number of <type>cl_device_id</type> entries. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>out_devices</varname></term> |
| <listitem> |
| <para> |
| The buffer where the OpenCL sub-devices will be returned. If |
| <varname>out_devices</varname> is NULL, this argument is ignored. If |
| <varname>out_devices</varname> is not NULL, <varname>num_devices</varname> |
| must be greater than or equal to the number of sub-devices that |
| <varname>device</varname> may be partitioned into according to the |
| partitioning scheme specified in <varname>properties</varname>. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>num_devices_ret</varname></term> |
| <listitem> |
| <para> |
| Returns the number of sub-devices that device may be |
| partitioned into according to the partitioning scheme specified in |
| <varname>properties</varname>. If <varname>num_devices_ret</varname> |
| is NULL, it is ignored. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| </variablelist> |
| </refsect1> |
| |
| <!-- ================================ NOTES --> |
| |
| <refsect1 id="notes"><title>Notes</title> |
| <para> |
| Creates an array of sub-devices that each reference a non-intersecting set of compute |
| units within <varname>in_device</varname>, according to a partition scheme given |
| by <varname>properties</varname>. The output sub-devices may be used in every way |
| that the root (or parent) device can be used, including creating contexts, building |
| programs, further calls to <function>clCreateSubDevices</function> and creating |
| command-queues. When a command-queue is created against a sub-device, the commands |
| enqueued on the queue are executed only on the sub-device. |
| </para> |
| </refsect1> |
| |
| <!-- ================================ ERRORS --> |
| |
| <refsect1 id="errors"><title>Errors</title> |
| <para> |
| Returns <errorname>CL_SUCCESS</errorname> if the partition is created successfully. |
| Otherwise, it returns a NULL value with the following error values returned in |
| <varname>errcode_ret</varname>: |
| </para> |
| |
| <itemizedlist mark="disc"> |
| <listitem> |
| <errorname>CL_INVALID_DEVICE</errorname> if <varname>in_device</varname> is not valid. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_INVALID_VALUE</errorname> if values specified in |
| <varname>properties</varname> are not valid or if values specified in |
| <varname>properties</varname> are valid but not supported by the device. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_INVALID_VALUE</errorname> if <varname>out_devices</varname> is not |
| NULL and <varname>num_devices</varname> is less than the number of sub-devices |
| created by the partition scheme. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_DEVICE_PARTITION_FAILED</errorname> if the partition name is |
| supported by the implementation but <varname>in_device</varname> could not be |
| further partitioned. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_INVALID_DEVICE_PARTITION_COUNT</errorname> if |
| the partition name specified in <varname>properties</varname> is |
| <constant>CL_DEVICE_PARTITION_BY_COUNTS</constant> and the number of sub-devices |
| requested exceeds <constant>CL_DEVICE_PARTITION_MAX_SUB_DEVICES</constant> |
| or the total number of compute units requested exceeds |
| <constant>CL_DEVICE_PARTITION_MAX_COMPUTE_UNITS</constant> for |
| <varname>in_device</varname>, or the number of compute units requested |
| for one or more sub-devices is less than zero or the number of sub-devices |
| requested exceeds <constant>CL_DEVICE_PARTITION_MAX_COMPUTE_UNITS</constant> |
| for <varname>in_device</varname>. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_OUT_OF_RESOURCES</errorname> if there is a failure to allocate |
| resources required by the OpenCL implementation on the device. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_OUT_OF_HOST_MEMORY</errorname> if there is a failure to allocate |
| resources required by the OpenCL implementation on the host. |
| </listitem> |
| </itemizedlist> |
| </refsect1> |
| |
| <!-- ================================ EXAMPLE --> |
| <!-- DO NOT DELETE IN CASE AN EXAMPLE IS ADDED IN THE FUTURE --> |
| <!-- --> |
| |
| <refsect2 id="example1"> |
| <title> |
| Example |
| </title> |
| |
| <para> |
| A few examples that describe how to specify partition properties in |
| <varname>properties</varname> argument to <function>clCreateSubDevices</function> |
| are given below. |
| </para> |
| |
| <para> |
| To partition a device containing 16 compute units into two sub-devices, each containing |
| 8 compute units, pass the following in <varname>properties</varname>: |
| </para> |
| |
| <informaltable frame="none"> |
| <tgroup cols="1" align="left" colsep="0" rowsep="0"> |
| <colspec colname="col1" colnum="1" /> <tbody> |
| <row> |
| <entry> |
| { CL_DEVICE_PARTITION_EQUALLY, 8, 0 } |
| </entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </informaltable> |
| |
| <para> |
| To partition a device with four compute units into two sub-devices with one sub-device |
| containing 3 compute units and the other sub-device 1 compute unit, pass the following |
| in <varname>properties</varname> argument: |
| </para> |
| |
| <informaltable frame="none"> |
| <tgroup cols="1" align="left" colsep="0" rowsep="0"> |
| <colspec colname="col1" colnum="1" /> <tbody> |
| <row> |
| <entry> |
| { CL_DEVICE_PARTITION_BY_COUNTS, |
| 3, 1, CL_DEVICE_PARTITION_BY_COUNTS_LIST_END, 0 } |
| </entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </informaltable> |
| |
| <para> |
| To split a device along the outermost cache line (if any), pass the following in |
| <varname>properties</varname> argument: |
| </para> |
| |
| <informaltable frame="none"> |
| <tgroup cols="1" align="left" colsep="0" rowsep="0"> |
| <colspec colname="col1" colnum="1" /> <tbody> |
| <row> |
| <entry> |
| { CL_DEVICE_PARTITION_BY_AFFINITY_DOMAIN, |
| CL_DEVICE_AFFINITY_DOMAIN_NEXT_PARTITIONABLE, 0 } |
| </entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </informaltable> |
| </refsect2> |
| |
| <!-- ================================ SPECIFICATION --> |
| <!-- Set the "uri" attribute in the <olink /> element to the "named destination" for the PDF page |
| --> |
| |
| <refsect1 id="specification"><title>Specification</title> |
| <para> |
| <imageobject> |
| <imagedata fileref="pdficon_small1.gif" format="gif" /> |
| </imageobject> |
| |
| <olink uri="clCreateSubDevices">OpenCL Specification</olink> |
| </para> |
| </refsect1> |
| |
| <!-- ================================ ALSO SEE --> |
| |
| <refsect1 id="seealso"><title>Also see</title> |
| <para> |
| <citerefentry><refentrytitle>clGetDeviceInfo</refentrytitle></citerefentry> |
| </para> |
| </refsect1> |
| |
| <!-- ================================ COPYRIGHT --> |
| <!-- Content included from copyright.inc.xsl --> |
| |
| <refsect3 id="Copyright"><title></title> |
| <imageobject> |
| <imagedata fileref="KhronosLogo.jpg" format="jpg" /> |
| </imageobject> |
| <para /> |
| </refsect3> |
| |
| <!-- 5-May-2013 --> |
| </refentry> |
| |
