ringkernel-derive

Procedural macros for RingKernel.

Overview

This crate provides derive macros and attribute macros for defining RingKernel messages, handlers, and GPU kernels.

Macros

#[derive(RingMessage)]

Implements the RingMessage trait for message types:

use ringkernel_derive::RingMessage;

#[derive(RingMessage)]
#[message(type_id = 1)]
struct MyMessage {
    #[message(id)]
    id: MessageId,
    #[message(correlation)]
    correlation: CorrelationId,
    #[message(priority)]
    priority: Priority,
    payload: Vec<f32>,
}

Struct attributes:

• #[message(type_id = N)] - Explicit message type ID (optional, auto-generated from name hash if omitted)

Field attributes:

• #[message(id)] - Mark as message ID field
• #[message(correlation)] - Mark as correlation ID field
• #[message(priority)] - Mark as priority field

#[ring_kernel]

Defines a ring kernel handler with metadata:

use ringkernel_derive::ring_kernel;

#[ring_kernel(id = "processor", mode = "persistent", block_size = 128)]
async fn handle(ctx: &mut RingContext, msg: MyMessage) -> MyResponse {
    MyResponse {
        id: MessageId::generate(),
        result: msg.a + msg.b,
    }
}

Attributes:

• id (required) - Unique kernel identifier
• mode - "persistent" (default) or "event_driven"
• grid_size - Number of blocks (default: 1)
• block_size - Threads per block (default: 256)
• publishes_to - Comma-separated list of target kernel IDs

#[derive(GpuType)]

Marks a type as GPU-compatible for direct transfer:

use ringkernel_derive::GpuType;

#[derive(Copy, Clone, GpuType)]
#[repr(C)]
struct Matrix4x4 {
    data: [f32; 16],
}

Generates compile-time assertions for Copy and implements bytemuck::Pod and bytemuck::Zeroable.

#[stencil_kernel]

Defines a stencil kernel that transpiles to CUDA (requires cuda-codegen feature):

use ringkernel_derive::stencil_kernel;

#[stencil_kernel(id = "fdtd", grid = "2d", tile_size = 16, halo = 1)]
fn fdtd(p: &[f32], p_prev: &mut [f32], c2: f32, pos: GridPos) {
    let curr = p[pos.idx()];
    let lap = pos.north(p) + pos.south(p) + pos.east(p) + pos.west(p) - 4.0 * curr;
    p_prev[pos.idx()] = 2.0 * curr - p_prev[pos.idx()] + c2 * lap;
}

// Access generated CUDA source:
assert!(FDTD_CUDA_SOURCE.contains("__global__"));

Attributes:

• id (required) - Kernel identifier
• grid - "1d", "2d" (default), or "3d"
• tile_size - Square tile size (default: 16)
• tile_width / tile_height - Non-square tile dimensions
• halo - Stencil radius (default: 1)

Generated Code

The macros generate:

• Trait implementations (RingMessage)
• Handler wrapper functions
• Kernel registration via inventory
• CUDA source constants (for stencil_kernel)

Testing

cargo test -p ringkernel-derive

The crate includes 14 tests covering all macro functionality.

License

Apache-2.0