Struct UpsampleNearest2dBackward 

pub struct UpsampleNearest2dBackward<D: Num> {
    pub name: &'static str,
    pub id: String,
    pub scale_h: i32,
    pub scale_w: i32,
    pub block_iw: i32,
    pub kernel_source: String,
    pub entry_point_source: String,
    pub source: String,
    /* private fields */
}

Nearest-neighbour 2-D upsample backward pass — NCHW layout.

Grid: one flat pid per (b, c, ih, iw-tile) — same spatial extent as the input tensor: pid = ((b * C + c) * H + ih) * num_iw_tiles + iw_tile

Each CTA computes the gradient for a BLOCK_IW-wide strip of input columns by summing the SCALE_H × SCALE_W upstream gradients that each input pixel received during the forward pass. No atomic operations are needed because each input element is the sole accumulator for exactly SCALE_H×SCALE_W output lanes (their ranges are disjoint).

dx does NOT need to be zero-initialised (every element is written once).

Fields

name: &'static str

The kernel function’s name (e.g. "flash_attention2_forward").

id: String

Unique kernel identifier: fn_name + dtype(s) + const values joined by “__”.

scale_h: i32

Compile-time kernel constant, from the annotated fn’s const generics.

scale_w: i32

Compile-time kernel constant, from the annotated fn’s const generics.

block_iw: i32

Compile-time kernel constant, from the annotated fn’s const generics.

kernel_source: String

The original kernel function source.

entry_point_source: String

The Rust source of the generated C-ABI entry-point wrapper function.

source: String

Combined source (kernel_source + "\n\n" + entry_point_source); used by the Kernel trait.

Implementations

impl<D: Num> UpsampleNearest2dBackward<D>

pub fn new(scale_h: i32, scale_w: i32, block_iw: i32) -> Self

Constructs a new kernel instance for these compile-time parameters.

Trait Implementations

impl<D: Num> Kernel for UpsampleNearest2dBackward<D>

type Args<'__a> = (*mut D, *mut D, i32, i32, i32, i32, i32, i32)

This kernel’s launch-argument tuple type.

fn id(&self) -> String

A content hash of this kernel’s source, used as a cache key.

fn name(&self) -> &str

This kernel’s name.

fn source(&self) -> &str

This kernel’s full source (DSL + kernel body + entry point wrapper).

fn kernel_source(&self) -> &str

This kernel’s body source, without the entry-point wrapper.

fn entry_point_source(&self) -> &str

Returns the Rust source of the generated C-ABI entry-point wrapper function.

fn entry_point_name(&self) -> String

Returns the PTX symbol name for this kernel: "{name}_entry_point".