Struct Context

pub struct Context { /* private fields */ }

Owned handle to a CUDA context.

The context will be destroyed when this goes out of scope. If this is the current context on the current OS thread, the next context on the stack (if any) will be made current. Note that the context will be destroyed even if other threads are still using it. Attempts to access the destroyed context from another thread will return an error.

Implementations

impl Context

pub fn create_and_push( flags: ContextFlags, device: Device, ) -> CudaResult<Context>

Create a CUDA context for the given device.

Example

rustacuda::init(rustacuda::CudaFlags::empty())?;
let device = Device::get_device(0)?;
let context = Context::create_and_push(ContextFlags::MAP_HOST | ContextFlags::SCHED_AUTO, device)?;

Examples found in repository

examples/launch.rs (line 12)

fn main() -> Result<(), Box<dyn Error>> {
    // Set up the context, load the module, and create a stream to run kernels in.
    rustacuda::init(CudaFlags::empty())?;
    let device = Device::get_device(0)?;
    let _ctx = Context::create_and_push(ContextFlags::MAP_HOST | ContextFlags::SCHED_AUTO, device)?;

    let ptx = CString::new(include_str!("../resources/add.ptx"))?;
    let module = Module::load_from_string(&ptx)?;
    let stream = Stream::new(StreamFlags::NON_BLOCKING, None)?;

    // Create buffers for data
    let mut in_x = DeviceBuffer::from_slice(&[1.0f32; 10])?;
    let mut in_y = DeviceBuffer::from_slice(&[2.0f32; 10])?;
    let mut out_1 = DeviceBuffer::from_slice(&[0.0f32; 10])?;
    let mut out_2 = DeviceBuffer::from_slice(&[0.0f32; 10])?;

    // This kernel adds each element in `in_x` and `in_y` and writes the result into `out`.
    unsafe {
        // Launch the kernel with one block of one thread, no dynamic shared memory on `stream`.
        let result = launch!(module.sum<<<1, 1, 0, stream>>>(
            in_x.as_device_ptr(),
            in_y.as_device_ptr(),
            out_1.as_device_ptr(),
            out_1.len()
        ));
        result?;

        // Launch the kernel again using the `function` form:
        let function_name = CString::new("sum")?;
        let sum = module.get_function(&function_name)?;
        // Launch with 1x1x1 (1) blocks of 10x1x1 (10) threads, to show that you can use tuples to
        // configure grid and block size.
        let result = launch!(sum<<<(1, 1, 1), (10, 1, 1), 0, stream>>>(
            in_x.as_device_ptr(),
            in_y.as_device_ptr(),
            out_2.as_device_ptr(),
            out_2.len()
        ));
        result?;
    }

    // Kernel launches are asynchronous, so we wait for the kernels to finish executing.
    stream.synchronize()?;

    // Copy the results back to host memory
    let mut out_host = [0.0f32; 20];
    out_1.copy_to(&mut out_host[0..10])?;
    out_2.copy_to(&mut out_host[10..20])?;

    for x in out_host.iter() {
        assert_eq!(3.0 as u32, *x as u32);
    }

    println!("Launched kernel successfully.");
    Ok(())
}

pub fn get_api_version(&self) -> CudaResult<CudaApiVersion>

Get the API version used to create this context.

This is not necessarily the latest version supported by the driver.

Example

rustacuda::init(rustacuda::CudaFlags::empty())?;
let device = Device::get_device(0)?;
let context = Context::create_and_push(ContextFlags::MAP_HOST | ContextFlags::SCHED_AUTO, device)?;
let version = context.get_api_version()?;

pub fn get_unowned(&self) -> UnownedContext

Returns an non-owning handle to this context.

This is useful for sharing a single context between threads (though see the module-level documentation for safety details!).

Example

let context = Context::create_and_push(ContextFlags::MAP_HOST | ContextFlags::SCHED_AUTO, device)?;
let unowned = context.get_unowned();

pub fn drop(ctx: Context) -> DropResult<Context>

Destroy a Context, returning an error.

Destroying a context can return errors from previous asynchronous work. This function destroys the given context and returns the error and the un-destroyed context on failure.

Example

let context = Context::create_and_push(ContextFlags::MAP_HOST | ContextFlags::SCHED_AUTO, device)?;
match Context::drop(context) {
    Ok(()) => println!("Successfully destroyed"),
    Err((e, ctx)) => {
        println!("Failed to destroy context: {:?}", e);
        // Do something with ctx
    },
}

Trait Implementations

impl Debug for Context

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Drop for Context

fn drop(&mut self)

Executes the destructor for this type.

impl ContextHandle for Context