thrust/cub/grid/grid_mapping.cuh

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/**
 * \file
 * cub::GridMappingStrategy enumerates alternative strategies for mapping constant-sized tiles of device-wide data onto a grid of CUDA thread blocks.
 */

#pragma once

#include "../config.cuh"

/// Optional outer namespace(s)
CUB_NS_PREFIX

/// CUB namespace
namespace cub {


/**
 * \addtogroup GridModule
 * @{
 */


/******************************************************************************
 * Mapping policies
 *****************************************************************************/


/**
 * \brief cub::GridMappingStrategy enumerates alternative strategies for mapping constant-sized tiles of device-wide data onto a grid of CUDA thread blocks.
 */
enum GridMappingStrategy
{
    /**
     * \brief An a "raking" access pattern in which each thread block is
     * assigned a consecutive sequence of input tiles
     *
     * \par Overview
     * The input is evenly partitioned into \p p segments, where \p p is
     * constant and corresponds loosely to the number of thread blocks that may
     * actively reside on the target device. Each segment is comprised of
     * consecutive tiles, where a tile is a small, constant-sized unit of input
     * to be processed to completion before the thread block terminates or
     * obtains more work.  The kernel invokes \p p thread blocks, each
     * of which iteratively consumes a segment of <em>n</em>/<em>p</em> elements
     * in tile-size increments.
     */
    GRID_MAPPING_RAKE,

    /**
     * \brief An a "strip mining" access pattern in which the input tiles assigned
     * to each thread block are separated by a stride equal to the the extent of
     * the grid.
     *
     * \par Overview
     * The input is evenly partitioned into \p p sets, where \p p is
     * constant and corresponds loosely to the number of thread blocks that may
     * actively reside on the target device. Each set is comprised of
     * data tiles separated by stride \p tiles, where a tile is a small,
     * constant-sized unit of input to be processed to completion before the
     * thread block terminates or obtains more work.  The kernel invokes \p p
     * thread blocks, each of which iteratively consumes a segment of
     * <em>n</em>/<em>p</em> elements in tile-size increments.
     */
    GRID_MAPPING_STRIP_MINE,

    /**
     * \brief A dynamic "queue-based" strategy for assigning input tiles to thread blocks.
     *
     * \par Overview
     * The input is treated as a queue to be dynamically consumed by a grid of
     * thread blocks.  Work is atomically dequeued in tiles, where a tile is a
     * unit of input to be processed to completion before the thread block
     * terminates or obtains more work.  The grid size \p p is constant,
     * loosely corresponding to the number of thread blocks that may actively
     * reside on the target device.
     */
    GRID_MAPPING_DYNAMIC,
};


/** @} */       // end group GridModule

}               // CUB namespace
CUB_NS_POSTFIX  // Optional outer namespace(s)